From patchwork Fri Nov 8 15:36:53 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 842214 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B998F21A6FE; Fri, 8 Nov 2024 15:37:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.200 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731080233; cv=none; b=mTT4D+Hq2nE5aPWfESuSjcYJgbtr4VHRzF1GKx4JkjL0OPO63rmO9PWT6hHvceMXxDiaurLGVmLYZsx3K4EkPXvgQ+b1IXIgienzXC/9BDHsse2mlQTjvq2oljiNkbfGfSYIEPUmAHl95JxrZYpGCOF4ak8BCfmcSX2P619HB1A= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731080233; c=relaxed/simple; bh=MTY9xEopYlaJ6Ma5ORg47HpjVWl/mUkPHEg2+gJWYy8=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=dz/bXiE5y6aMgyeH7+8Y7aYzwXknTWuyBlR7aFQ2l6jRCESOzZw1LvQNcK355zmHJYLszFgGxO2ldJ0oCWeY9eXV6wqf0JPLTNP8/QpPlXSbR3Wh0pTV5PbeYNU+rgKGKZUKdB2iCFF4whN1sKNqN6gjJtHgBx+x7F/B+1ZGGFs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=EmgdkVTX; arc=none smtp.client-ip=217.70.183.200 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="EmgdkVTX" Received: by mail.gandi.net (Postfix) with ESMTPSA id 557F020002; Fri, 8 Nov 2024 15:37:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731080229; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Hhy3CLpNo/bicvB34YCbZy2/E3Zufk2BHGhPhGi+xEM=; b=EmgdkVTXDftgSfRZZDCFp2Vv2CsV8UsOjg6VWe4AkPD1iIFccrHAWkUi/oZiS+mQhUoV37 kCrWIf74JeqpjNRltXIPUMwwn6mwebjDO70ZTshQsoY1I0yXKOVBTXzbcJe+JMiVy3ggCm hwFo1hHNAoc8Hwiy2elcH2Vu78/YUq5PoEvut2fiV1HfPrJibxygz8CzZdLjhjZvWAJUIn IcLPFYUtKgyJZCKpxyDUqwOis76d4qALsxHDBnfFJZaip9KVDd+M6vSIQ7hSF6czz4h/n3 tSdXiUShe2Oh+FIn4v6XKLZ/1Y0Y9nalUdHuV9oRFto999fKj+TbNqBDhCZgqg== From: Romain Gantois Date: Fri, 08 Nov 2024 16:36:53 +0100 Subject: [PATCH 1/9] dt-bindings: misc: Describe TI FPC202 dual port controller Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241108-fpc202-v1-1-fe42c698bc92@bootlin.com> References: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> In-Reply-To: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com The FPC202 dual port controller serves as a low speed signal aggregator for common port types, notably SFP. It provides access to I2C and low-speed GPIO signals of a downstream device through a single upstream control interface. Up to two logical I2C addresses can be accessed on each of the FPC202's ports. The port controller acts as an I2C translator (ATR). It converts addresses of incoming and outgoing I2C transactions. One use case of this is accessing two SFP modules at logical address 0x50 from the same upstream I2C controller, using two different client aliases. Signed-off-by: Romain Gantois --- .../devicetree/bindings/misc/ti,fpc202.yaml | 75 ++++++++++++++++++++++ 1 file changed, 75 insertions(+) diff --git a/Documentation/devicetree/bindings/misc/ti,fpc202.yaml b/Documentation/devicetree/bindings/misc/ti,fpc202.yaml new file mode 100644 index 0000000000000000000000000000000000000000..ad11abe11e68aa266acdd6b43a5b425340bbbba8 --- /dev/null +++ b/Documentation/devicetree/bindings/misc/ti,fpc202.yaml @@ -0,0 +1,75 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/misc/ti,fpc202.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: TI FPC202 dual port controller with expanded IOs + +maintainers: + - Romain Gantois + +allOf: + - $ref: /schemas/i2c/i2c-atr.yaml# + +properties: + compatible: + const: ti,fpc202 + + reg: + maxItems: 1 + + gpio-controller: true + + "#gpio-cells": + const: 2 + + enable-gpios: + description: + Specifier for the GPIO connected to the EN pin. + maxItems: 1 + + port0: + $ref: /schemas/i2c/i2c-controller.yaml + description: + Device port 0, accessible over I2C. + + port1: + $ref: /schemas/i2c/i2c-controller.yaml + description: + Device port 1, accessible over I2C. + + +required: + - compatible + - gpio-controller + - "#gpio-cells" + - reg + +unevaluatedProperties: false + +examples: + - | + i2c { + #address-cells = <1>; + #size-cells = <0>; + + fpc202: i2c-mux@f { + compatible = "ti,fpc202"; + reg = <0xf>; + + gpio-controller; + #gpio-cells = <2>; + + port0 { + #address-cells = <1>; + #size-cells = <0>; + }; + + port1 { + #address-cells = <1>; + #size-cells = <0>; + }; + }; + }; +... From patchwork Fri Nov 8 15:36:54 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 841834 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C6C2F21A704; Fri, 8 Nov 2024 15:37:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.200 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731080234; cv=none; b=Q/zEZyM8t4pLx1fUBiffHEjiWzCtT1CUlScJY6XixQEOIflk5rz8ozgEUT3ufw2Qs4ixzgjLy/pLriU2R3ptYo6a1sfr0v8WdG95VGSK+5OLslzgd/4RURTrZMkM3QjUMkcHzSIIJ4kWVFbdme6M4c3ICXSi+k7YM5M/4Q/VaVk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731080234; c=relaxed/simple; bh=1ypPzc3wV+lBm0DYM/aNzTLOzfM+uS1LxxpyOA8V4G8=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=CZyVumgKRSzOZOOEQRpiNVUn1Ce0NmvrWO4E0CnwtWnbfWbymZYADYdllEEEpcN6HV4o3SDT+6MsUD7sTCEKh9bRksVQ/z+fYt9czmu7/20c6jKe3h9T8UYBdH33RXOTwg31FFbdFRbOelcPbjznvlk21MgTUhis30iwaM+w43Q= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=RdHcc/qu; arc=none smtp.client-ip=217.70.183.200 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="RdHcc/qu" Received: by mail.gandi.net (Postfix) with ESMTPSA id 58B322000B; Fri, 8 Nov 2024 15:37:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731080230; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=sFZV/j2cdKSUUBE7wpD1K2bQ3OXCC6ZtMchgh75jPUI=; b=RdHcc/quHj39f7IVeGSH6D28RaxUwLToaFRa+6LfyztqF/cHy+j6MN+KXSuPHOTPBO8loZ UXGOhvC04vxwAaPkCbsaWBBs9X2mZdHh7Iu6Dz86tA3HF5ypt0UT2hNleh8IcdUAROz4gN ZcW1H0BM4vfetLuNu9+ALmTTHAr0yNSPCfA7/6IkOhtmWwZcxem7e6NXEeRMfPUWEpZJpM mbTXDAVX/yOQz0vQrGv10wt8gbDxu0d/WPmdJhmPQtZLhG0VtEao9F8pniSmNK0xNflthl 0K3OLbNAxo9O/Usw294hYzdFMAnGWHCQhsDBH+vLXJ4X7D3pYZ9mejjQ8cTBJQ== From: Romain Gantois Date: Fri, 08 Nov 2024 16:36:54 +0100 Subject: [PATCH 2/9] media: i2c: ds90ub960: Replace aliased clients list with bitmap Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241108-fpc202-v1-2-fe42c698bc92@bootlin.com> References: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> In-Reply-To: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com The ds90ub960 driver currently uses a list of i2c_client structs to keep track of used I2C address translator (ATR) alias slots for each RX port. Keeping these i2c_client structs in the alias slot list isn't actually needed, the driver only needs to know if a specific alias slot is already in use or not. Convert the aliased_clients list to a bitmap named "alias_use_mask". This will allow removing the "client" parameter from the i2c-atr callbacks in a future patch. Signed-off-by: Romain Gantois --- drivers/media/i2c/ds90ub960.c | 23 +++++++++-------------- 1 file changed, 9 insertions(+), 14 deletions(-) diff --git a/drivers/media/i2c/ds90ub960.c b/drivers/media/i2c/ds90ub960.c index ffe5f25f8647624be005da33a6412da2493413b4..f86028894c78187257efc8fd70812387000796f7 100644 --- a/drivers/media/i2c/ds90ub960.c +++ b/drivers/media/i2c/ds90ub960.c @@ -468,7 +468,7 @@ struct ub960_rxport { }; } eq; - const struct i2c_client *aliased_clients[UB960_MAX_PORT_ALIASES]; + DECLARE_BITMAP(alias_use_mask, UB960_MAX_PORT_ALIASES); }; struct ub960_asd { @@ -1032,17 +1032,13 @@ static int ub960_atr_attach_client(struct i2c_atr *atr, u32 chan_id, struct device *dev = &priv->client->dev; unsigned int reg_idx; - for (reg_idx = 0; reg_idx < ARRAY_SIZE(rxport->aliased_clients); reg_idx++) { - if (!rxport->aliased_clients[reg_idx]) - break; - } - - if (reg_idx == ARRAY_SIZE(rxport->aliased_clients)) { + reg_idx = find_first_zero_bit(rxport->alias_use_mask, UB960_MAX_PORT_ALIASES); + if (reg_idx >= UB960_MAX_PORT_ALIASES) { dev_err(dev, "rx%u: alias pool exhausted\n", rxport->nport); return -EADDRNOTAVAIL; } - rxport->aliased_clients[reg_idx] = client; + set_bit(reg_idx, rxport->alias_use_mask); ub960_rxport_write(priv, chan_id, UB960_RR_SLAVE_ID(reg_idx), client->addr << 1); @@ -1063,18 +1059,15 @@ static void ub960_atr_detach_client(struct i2c_atr *atr, u32 chan_id, struct device *dev = &priv->client->dev; unsigned int reg_idx; - for (reg_idx = 0; reg_idx < ARRAY_SIZE(rxport->aliased_clients); reg_idx++) { - if (rxport->aliased_clients[reg_idx] == client) - break; - } + reg_idx = find_first_zero_bit(rxport->alias_use_mask, UB960_MAX_PORT_ALIASES); - if (reg_idx == ARRAY_SIZE(rxport->aliased_clients)) { + if (reg_idx >= UB960_MAX_PORT_ALIASES) { dev_err(dev, "rx%u: client 0x%02x is not mapped!\n", rxport->nport, client->addr); return; } - rxport->aliased_clients[reg_idx] = NULL; + clear_bit(reg_idx, rxport->alias_use_mask); ub960_rxport_write(priv, chan_id, UB960_RR_SLAVE_ALIAS(reg_idx), 0); @@ -3404,6 +3397,8 @@ static int ub960_parse_dt_rxport(struct ub960_data *priv, unsigned int nport, if (ret) goto err_put_remote_fwnode; + bitmap_zero(rxport->alias_use_mask, UB960_MAX_PORT_ALIASES); + return 0; err_put_remote_fwnode: From patchwork Fri Nov 8 15:36:55 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 842213 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D758621A706; Fri, 8 Nov 2024 15:37:12 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.200 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731080235; cv=none; b=mOctDJ6fuGMjZfM+Pul5sJgT0kT8kjHHrCWWQWzWB8vb1qNLdA0i5BNzYSKqguMOLcUOCqlsiLReznfgttAQ/wWWvVi4yz09cfMoONwKI0HK2OREswdGzxUk24YuGEXLJX6OFCvBOvy7m6ImiBjEaEdfOXof6Hly4j/PWIQPhZk= ARC-Message-Signature: i=1; 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Fri, 8 Nov 2024 15:37:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731080231; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=P5zllN3RyR2rCAMaUjg2lao0VPW3ctT8CwfZRn1byPs=; b=NArO5Wd1+77yUPdtcaoTGcIvncRQPlSiHGLTh08Xc55kqFA9jaXn5SM8/LY+xRB/1FDIV2 YPsW2FnaP1lizOYKPTn7HgxWT0VbSmg4QYcSEZsJptjypvVnby1elstM36REQFG949u6sv nr22zJWgUV1CCrFqpNXVzwy3WnKxWYIlZdM/qNb5yPtpastiW73LiePOHksw/aqWoMB5qi nTtP5gp6dZm+gVtfpILala1C8LM+o7JafA6Fn8o17P/B6za0BFN1V+Lu9u+W98QDErdLeb SkEBLZQU02HNaj1WrXID7+4ovxCUM+ob6QEVh0F3zihKU4NDA1NE/xfBifxMUA== From: Romain Gantois Date: Fri, 08 Nov 2024 16:36:55 +0100 Subject: [PATCH 3/9] media: i2c: ds90ub960: Protect alias_use_mask with a mutex Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241108-fpc202-v1-3-fe42c698bc92@bootlin.com> References: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> In-Reply-To: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com The alias_use_mask bitmap represents the occupation of an RX port's hardware alias table. This bitmap and the underlying hardware table are only accessed in the attach/detach_client() callbacks. These functions are only called from a bus notifier handler in i2c-atr.c, which is always called with the notifier chain's semaphore held. This indirectly prevents concurrent access to the alias_use_mask bitmap. However, more explicit and direct locking is preferable. Moreover, with the introduction of dynamic address translation in a future patch, the attach/detach_client() callbacks will be called from outside of the notifier chain's read section. Introduce a mutex to protect access to the alias_use_mask bitmap and its underlying hardware table. Signed-off-by: Romain Gantois --- drivers/media/i2c/ds90ub960.c | 22 +++++++++++++++++++--- 1 file changed, 19 insertions(+), 3 deletions(-) diff --git a/drivers/media/i2c/ds90ub960.c b/drivers/media/i2c/ds90ub960.c index f86028894c78187257efc8fd70812387000796f7..84aa976bed2d74f1d639684601f4c1c38d748188 100644 --- a/drivers/media/i2c/ds90ub960.c +++ b/drivers/media/i2c/ds90ub960.c @@ -468,6 +468,8 @@ struct ub960_rxport { }; } eq; + /* lock for alias_use_mask and associated registers */ + struct mutex alias_mask_lock; DECLARE_BITMAP(alias_use_mask, UB960_MAX_PORT_ALIASES); }; @@ -1031,11 +1033,15 @@ static int ub960_atr_attach_client(struct i2c_atr *atr, u32 chan_id, struct ub960_rxport *rxport = priv->rxports[chan_id]; struct device *dev = &priv->client->dev; unsigned int reg_idx; + int ret = 0; + + mutex_lock(&rxport->alias_mask_lock); reg_idx = find_first_zero_bit(rxport->alias_use_mask, UB960_MAX_PORT_ALIASES); if (reg_idx >= UB960_MAX_PORT_ALIASES) { dev_err(dev, "rx%u: alias pool exhausted\n", rxport->nport); - return -EADDRNOTAVAIL; + ret = -EADDRNOTAVAIL; + goto out_unlock; } set_bit(reg_idx, rxport->alias_use_mask); @@ -1048,7 +1054,9 @@ static int ub960_atr_attach_client(struct i2c_atr *atr, u32 chan_id, dev_dbg(dev, "rx%u: client 0x%02x assigned alias 0x%02x at slot %u\n", rxport->nport, client->addr, alias, reg_idx); - return 0; +out_unlock: + mutex_unlock(&rxport->alias_mask_lock); + return ret; } static void ub960_atr_detach_client(struct i2c_atr *atr, u32 chan_id, @@ -1059,12 +1067,14 @@ static void ub960_atr_detach_client(struct i2c_atr *atr, u32 chan_id, struct device *dev = &priv->client->dev; unsigned int reg_idx; + mutex_lock(&rxport->alias_mask_lock); + reg_idx = find_first_zero_bit(rxport->alias_use_mask, UB960_MAX_PORT_ALIASES); if (reg_idx >= UB960_MAX_PORT_ALIASES) { dev_err(dev, "rx%u: client 0x%02x is not mapped!\n", rxport->nport, client->addr); - return; + goto out_unlock; } clear_bit(reg_idx, rxport->alias_use_mask); @@ -1073,6 +1083,9 @@ static void ub960_atr_detach_client(struct i2c_atr *atr, u32 chan_id, dev_dbg(dev, "rx%u: client 0x%02x released at slot %u\n", rxport->nport, client->addr, reg_idx); + +out_unlock: + mutex_unlock(&rxport->alias_mask_lock); } static const struct i2c_atr_ops ub960_atr_ops = { @@ -3177,6 +3190,8 @@ static void ub960_rxport_free_ports(struct ub960_data *priv) fwnode_handle_put(rxport->source.ep_fwnode); fwnode_handle_put(rxport->ser.fwnode); + mutex_destroy(&rxport->alias_mask_lock); + kfree(rxport); priv->rxports[nport] = NULL; } @@ -3398,6 +3413,7 @@ static int ub960_parse_dt_rxport(struct ub960_data *priv, unsigned int nport, goto err_put_remote_fwnode; bitmap_zero(rxport->alias_use_mask, UB960_MAX_PORT_ALIASES); + mutex_init(&rxport->alias_mask_lock); return 0; From patchwork Fri Nov 8 15:36:56 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 841833 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B583621B425; 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arc=none smtp.client-ip=217.70.183.200 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="JI0s33Ei" Received: by mail.gandi.net (Postfix) with ESMTPSA id 4F48620010; Fri, 8 Nov 2024 15:37:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731080232; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=eDMqNXN+UYqyQqUu1V62RNFnYP8XOvywWsZyr2uIKsA=; b=JI0s33Ei7I72AFzZotpxa62seEaJrpxbi0WRmcqPdDdV9He7FYGQJN4mTY0v/GsHVNLv7U ccAxU0MwIb5NrOpdS8WRk9l/HisXA/rpvvXuD8pSxP4mpCTNSX2yd9fmr7b1TogWDgqNQr A7qZyhQeDTX/tTKrnhUid6V8WQp/2NoSEXo26iGz9Z40kysaIFOJbB/XzzVZnzM0WAMiQZ k0WQk/y7X4MlecrpWf+W72jWTKkqROiyzRWzSEFWLFbjVp2QxHbwaGJ3Qav6XazDZZ7Vjf usti4+pQzHpxK7oMHVo7Eh+eEcUuCi98SLVDuz5VMp9qi/D9uVoWkBfI88/31g== From: Romain Gantois Date: Fri, 08 Nov 2024 16:36:56 +0100 Subject: [PATCH 4/9] i2c: use client addresses directly in ATR interface Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241108-fpc202-v1-4-fe42c698bc92@bootlin.com> References: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> In-Reply-To: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com The I2C Address Translator (ATR) module defines mappings from i2c_client structs to aliases. However, only the physical address of each i2c_client struct is actually relevant to the workings of the ATR module. Moreover, some drivers require address translation functionality but do not allocate i2c_client structs, accessing the adapter directly instead. The SFP subsystem is an example of this. Replace the "i2c_client" field of the i2c_atr_alias_pair struct with a u16 "addr" field. Rewrite helper functions and callbacks as needed. Signed-off-by: Romain Gantois --- drivers/i2c/i2c-atr.c | 52 ++++++++++++++++--------------------------- drivers/media/i2c/ds90ub960.c | 20 ++++++++--------- include/linux/i2c-atr.h | 20 ++++++++--------- 3 files changed, 39 insertions(+), 53 deletions(-) diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c index f21475ae592183a45b5e46a20e7a0699fb88132c..894787246846b9965deb03a7ec7eb600b102ddad 100644 --- a/drivers/i2c/i2c-atr.c +++ b/drivers/i2c/i2c-atr.c @@ -21,16 +21,16 @@ #define ATR_MAX_SYMLINK_LEN 11 /* Longest name is 10 chars: "channel-99" */ /** - * struct i2c_atr_alias_pair - Holds the alias assigned to a client. + * struct i2c_atr_alias_pair - Holds the alias assigned to a client address. * @node: List node - * @client: Pointer to the client on the child bus + * @addr: Address of the client on the child bus. * @alias: I2C alias address assigned by the driver. * This is the address that will be used to issue I2C transactions * on the parent (physical) bus. */ struct i2c_atr_alias_pair { struct list_head node; - const struct i2c_client *client; + u16 addr; u16 alias; }; @@ -97,27 +97,13 @@ struct i2c_atr { struct i2c_adapter *adapter[] __counted_by(max_adapters); }; -static struct i2c_atr_alias_pair * -i2c_atr_find_mapping_by_client(const struct list_head *list, - const struct i2c_client *client) -{ - struct i2c_atr_alias_pair *c2a; - - list_for_each_entry(c2a, list, node) { - if (c2a->client == client) - return c2a; - } - - return NULL; -} - static struct i2c_atr_alias_pair * i2c_atr_find_mapping_by_addr(const struct list_head *list, u16 phys_addr) { struct i2c_atr_alias_pair *c2a; list_for_each_entry(c2a, list, node) { - if (c2a->client->addr == phys_addr) + if (c2a->addr == phys_addr) return c2a; } @@ -313,8 +299,8 @@ static void i2c_atr_release_alias(struct i2c_atr *atr, u16 alias) dev_warn(atr->dev, "Unable to find mapped alias\n"); } -static int i2c_atr_attach_client(struct i2c_adapter *adapter, - const struct i2c_client *client) +static int i2c_atr_attach_addr(struct i2c_adapter *adapter, + u16 addr) { struct i2c_atr_chan *chan = adapter->algo_data; struct i2c_atr *atr = chan->atr; @@ -334,14 +320,14 @@ static int i2c_atr_attach_client(struct i2c_adapter *adapter, goto err_release_alias; } - ret = atr->ops->attach_client(atr, chan->chan_id, client, alias); + ret = atr->ops->attach_addr(atr, chan->chan_id, addr, alias); if (ret) goto err_free; - dev_dbg(atr->dev, "chan%u: client 0x%02x mapped at alias 0x%02x (%s)\n", - chan->chan_id, client->addr, alias, client->name); + dev_dbg(atr->dev, "chan%u: addr 0x%02x mapped at alias 0x%02x\n", + chan->chan_id, addr, alias); - c2a->client = client; + c2a->addr = addr; c2a->alias = alias; list_add(&c2a->node, &chan->alias_list); @@ -355,16 +341,16 @@ static int i2c_atr_attach_client(struct i2c_adapter *adapter, return ret; } -static void i2c_atr_detach_client(struct i2c_adapter *adapter, - const struct i2c_client *client) +static void i2c_atr_detach_addr(struct i2c_adapter *adapter, + u16 addr) { struct i2c_atr_chan *chan = adapter->algo_data; struct i2c_atr *atr = chan->atr; struct i2c_atr_alias_pair *c2a; - atr->ops->detach_client(atr, chan->chan_id, client); + atr->ops->detach_addr(atr, chan->chan_id, addr); - c2a = i2c_atr_find_mapping_by_client(&chan->alias_list, client); + c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, addr); if (!c2a) { /* This should never happen */ dev_warn(atr->dev, "Unable to find address mapping\n"); @@ -374,8 +360,8 @@ static void i2c_atr_detach_client(struct i2c_adapter *adapter, i2c_atr_release_alias(atr, c2a->alias); dev_dbg(atr->dev, - "chan%u: client 0x%02x unmapped from alias 0x%02x (%s)\n", - chan->chan_id, client->addr, c2a->alias, client->name); + "chan%u: addr 0x%02x unmapped from alias 0x%02x\n", + chan->chan_id, addr, c2a->alias); list_del(&c2a->node); kfree(c2a); @@ -405,7 +391,7 @@ static int i2c_atr_bus_notifier_call(struct notifier_block *nb, switch (event) { case BUS_NOTIFY_ADD_DEVICE: - ret = i2c_atr_attach_client(client->adapter, client); + ret = i2c_atr_attach_addr(client->adapter, client->addr); if (ret) dev_err(atr->dev, "Failed to attach remote client '%s': %d\n", @@ -413,7 +399,7 @@ static int i2c_atr_bus_notifier_call(struct notifier_block *nb, break; case BUS_NOTIFY_DEL_DEVICE: - i2c_atr_detach_client(client->adapter, client); + i2c_atr_detach_addr(client->adapter, client->addr); break; default: @@ -506,7 +492,7 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, if (max_adapters > ATR_MAX_ADAPTERS) return ERR_PTR(-EINVAL); - if (!ops || !ops->attach_client || !ops->detach_client) + if (!ops || !ops->attach_addr || !ops->detach_addr) return ERR_PTR(-EINVAL); atr = kzalloc(struct_size(atr, adapter, max_adapters), GFP_KERNEL); diff --git a/drivers/media/i2c/ds90ub960.c b/drivers/media/i2c/ds90ub960.c index 84aa976bed2d74f1d639684601f4c1c38d748188..5a836731af6c701ef4070eb2dbab36cbdd86e0a2 100644 --- a/drivers/media/i2c/ds90ub960.c +++ b/drivers/media/i2c/ds90ub960.c @@ -1026,8 +1026,8 @@ static int ub960_ind_update_bits(struct ub960_data *priv, u8 block, u8 reg, * I2C-ATR (address translator) */ -static int ub960_atr_attach_client(struct i2c_atr *atr, u32 chan_id, - const struct i2c_client *client, u16 alias) +static int ub960_atr_attach_addr(struct i2c_atr *atr, u32 chan_id, + u16 addr, u16 alias) { struct ub960_data *priv = i2c_atr_get_driver_data(atr); struct ub960_rxport *rxport = priv->rxports[chan_id]; @@ -1047,20 +1047,20 @@ static int ub960_atr_attach_client(struct i2c_atr *atr, u32 chan_id, set_bit(reg_idx, rxport->alias_use_mask); ub960_rxport_write(priv, chan_id, UB960_RR_SLAVE_ID(reg_idx), - client->addr << 1); + addr << 1); ub960_rxport_write(priv, chan_id, UB960_RR_SLAVE_ALIAS(reg_idx), alias << 1); dev_dbg(dev, "rx%u: client 0x%02x assigned alias 0x%02x at slot %u\n", - rxport->nport, client->addr, alias, reg_idx); + rxport->nport, addr, alias, reg_idx); out_unlock: mutex_unlock(&rxport->alias_mask_lock); return ret; } -static void ub960_atr_detach_client(struct i2c_atr *atr, u32 chan_id, - const struct i2c_client *client) +static void ub960_atr_detach_addr(struct i2c_atr *atr, u32 chan_id, + u16 addr) { struct ub960_data *priv = i2c_atr_get_driver_data(atr); struct ub960_rxport *rxport = priv->rxports[chan_id]; @@ -1073,7 +1073,7 @@ static void ub960_atr_detach_client(struct i2c_atr *atr, u32 chan_id, if (reg_idx >= UB960_MAX_PORT_ALIASES) { dev_err(dev, "rx%u: client 0x%02x is not mapped!\n", - rxport->nport, client->addr); + rxport->nport, addr); goto out_unlock; } @@ -1082,15 +1082,15 @@ static void ub960_atr_detach_client(struct i2c_atr *atr, u32 chan_id, ub960_rxport_write(priv, chan_id, UB960_RR_SLAVE_ALIAS(reg_idx), 0); dev_dbg(dev, "rx%u: client 0x%02x released at slot %u\n", rxport->nport, - client->addr, reg_idx); + addr, reg_idx); out_unlock: mutex_unlock(&rxport->alias_mask_lock); } static const struct i2c_atr_ops ub960_atr_ops = { - .attach_client = ub960_atr_attach_client, - .detach_client = ub960_atr_detach_client, + .attach_addr = ub960_atr_attach_addr, + .detach_addr = ub960_atr_detach_addr, }; static int ub960_init_atr(struct ub960_data *priv) diff --git a/include/linux/i2c-atr.h b/include/linux/i2c-atr.h index 4d5da161c22516b3294e73702ace7a4546cdd588..14c1f9175c0db6a8a9c6ef5d771ae68361132a76 100644 --- a/include/linux/i2c-atr.h +++ b/include/linux/i2c-atr.h @@ -20,20 +20,20 @@ struct i2c_atr; /** * struct i2c_atr_ops - Callbacks from ATR to the device driver. - * @attach_client: Notify the driver of a new device connected on a child - * bus, with the alias assigned to it. The driver must - * configure the hardware to use the alias. - * @detach_client: Notify the driver of a device getting disconnected. The - * driver must configure the hardware to stop using the - * alias. + * @attach_addr: Notify the driver of a new device connected on a child + * bus, with the alias assigned to it. The driver must + * configure the hardware to use the alias. + * @detach_addr: Notify the driver of a device getting disconnected. The + * driver must configure the hardware to stop using the + * alias. * * All these functions return 0 on success, a negative error code otherwise. */ struct i2c_atr_ops { - int (*attach_client)(struct i2c_atr *atr, u32 chan_id, - const struct i2c_client *client, u16 alias); - void (*detach_client)(struct i2c_atr *atr, u32 chan_id, - const struct i2c_client *client); + int (*attach_addr)(struct i2c_atr *atr, u32 chan_id, + u16 addr, u16 alias); + void (*detach_addr)(struct i2c_atr *atr, u32 chan_id, + u16 addr); }; /** From patchwork Fri Nov 8 15:36:57 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 841832 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B2CD521B446; Fri, 8 Nov 2024 15:37:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.200 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731080238; cv=none; b=hl3cKePVbYea9UwAEA1yl20qCGhyXO0VdHXciwp5QRkgQyklWAubBh4bW0mP5G/0HYmWWKucwdqNr0KDFGNgQtVglhknpRNYgZtvrVFI/OGnaax/B85x6Kt1eCBy8mWExxOCHBzWYIafOq3cttJ0bXAKsI+qbMJ+xawG5g1IGRk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731080238; c=relaxed/simple; bh=kxeO51kOwYXUp0OU5P8vMOAk78cA1NW78/VhRsNmjZU=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=feRBP3TrxE6F0oOCg6im3Wm+pJy8v/ryvMPQ4A7AsoDecj6HXw702UTEocb8MIp0wd8X7KLRYefSZ+5QQVcuh12bhjFdzwuvryhQqHyY/70T97m85lqaUydm87VQ3QwymNU2zX/xL2CRsRSDk89tTxwBV1hXoZgP0LKEgItaSkc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=VIIWIdHc; arc=none smtp.client-ip=217.70.183.200 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="VIIWIdHc" Received: by mail.gandi.net (Postfix) with ESMTPSA id 49C3120011; Fri, 8 Nov 2024 15:37:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731080233; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=uO2oXC73Ucf+OKFHsX5fbRnrJrLCb2JkxdDG4pxP7Tk=; b=VIIWIdHc2Js3Bd0nuOxvJ5fVXFPvUg7YsxOG3K/6H/Cw+eYJki3MW5yAC+0BzZHFF7E+xc P6xTVUAP08a7qE075C9DDu+/P7MsIEWXzIrV9DOpdCgLiFwfQpkRThEXA/DHdj3T9B0F8i yeDkOwVD5Xpa4McBOvTscnyx/Tyt8/OpqltrCpYfOX5vvO0K8Rp5AL6Dmzxymk0jmq/JG4 WpAqunjgFx3gzLQ8EZ7QSMMfweLfpA3IEeMd+8gTQw0grdhSwt/6EpZ5uygkNsxByvrlkW yOKyqxrPaRBolQNQ8tBgui2FhiLHlm5Q8E3/20cm72VDimq0PQlaaXD6TOdffQ== From: Romain Gantois Date: Fri, 08 Nov 2024 16:36:57 +0100 Subject: [PATCH 5/9] i2c: move ATR alias pool to a separate struct Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241108-fpc202-v1-5-fe42c698bc92@bootlin.com> References: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> In-Reply-To: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com Each I2C address translator (ATR) has a pool of client aliases which can be used as translation targets. Some ATRs have a single alias pool shared by all downstream channels, while others have a separate alias pool for each channel. Currently, this alias pool is represented by the "aliases", "num_aliases", and "use_mask" fields of struct i2c_atr. In preparation for adding per-channel alias pool support, move the "aliases", "num_aliases", "use_mask" and associated lock to a new struct called "struct alias_pool". Signed-off-by: Romain Gantois --- drivers/i2c/i2c-atr.c | 172 +++++++++++++++++++++++++++++++------------------- 1 file changed, 107 insertions(+), 65 deletions(-) diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c index 894787246846b9965deb03a7ec7eb600b102ddad..c873fe52288175151040a4c32e6ed07735586004 100644 --- a/drivers/i2c/i2c-atr.c +++ b/drivers/i2c/i2c-atr.c @@ -34,6 +34,23 @@ struct i2c_atr_alias_pair { u16 alias; }; +/** + * struct i2c_atr_alias_pool - Pool of client aliases available for an ATR. + * @size: Total number of aliases + * + * @lock: Lock protecting @aliases and @use_mask + * @aliases: Array of aliases, must hold exactly @size elements + * @use_mask: Mask of used aliases + */ +struct i2c_atr_alias_pool { + size_t size; + + /* Protects aliases and use_mask */ + spinlock_t lock; + u16 *aliases; + unsigned long *use_mask; +}; + /** * struct i2c_atr_chan - Data for a channel. * @adap: The &struct i2c_adapter for the channel @@ -67,10 +84,7 @@ struct i2c_atr_chan { * @algo: The &struct i2c_algorithm for adapters * @lock: Lock for the I2C bus segment (see &struct i2c_lock_operations) * @max_adapters: Maximum number of adapters this I2C ATR can have - * @num_aliases: Number of aliases in the aliases array - * @aliases: The aliases array - * @alias_mask_lock: Lock protecting alias_use_mask - * @alias_use_mask: Bitmask for used aliases in aliases array + * @alias_pool: Pool of available client aliases * @i2c_nb: Notifier for remote client add & del events * @adapter: Array of adapters */ @@ -86,17 +100,54 @@ struct i2c_atr { struct mutex lock; int max_adapters; - size_t num_aliases; - const u16 *aliases; - /* Protects alias_use_mask */ - spinlock_t alias_mask_lock; - unsigned long *alias_use_mask; + struct i2c_atr_alias_pool *alias_pool; struct notifier_block i2c_nb; struct i2c_adapter *adapter[] __counted_by(max_adapters); }; +static struct i2c_atr_alias_pool *i2c_atr_alloc_alias_pool(size_t num_aliases) +{ + struct i2c_atr_alias_pool *alias_pool; + int ret; + + alias_pool = kzalloc(sizeof(*alias_pool), GFP_KERNEL); + if (!alias_pool) + return ERR_PTR(-ENOMEM); + + alias_pool->size = num_aliases; + + alias_pool->aliases = kcalloc(num_aliases, sizeof(*alias_pool->aliases), GFP_KERNEL); + if (!alias_pool->aliases) { + ret = -ENOMEM; + goto err_free_alias_pool; + } + + alias_pool->use_mask = bitmap_zalloc(num_aliases, GFP_KERNEL); + if (!alias_pool->use_mask) { + ret = -ENOMEM; + goto err_free_aliases; + } + + spin_lock_init(&alias_pool->lock); + + return alias_pool; + +err_free_aliases: + kfree(alias_pool->aliases); +err_free_alias_pool: + kfree(alias_pool); + return ERR_PTR(ret); +} + +static void i2c_atr_free_alias_pool(struct i2c_atr_alias_pool *alias_pool) +{ + bitmap_free(alias_pool->use_mask); + kfree(alias_pool->aliases); + kfree(alias_pool); +} + static struct i2c_atr_alias_pair * i2c_atr_find_mapping_by_addr(const struct list_head *list, u16 phys_addr) { @@ -259,44 +310,42 @@ static const struct i2c_lock_operations i2c_atr_lock_ops = { .unlock_bus = i2c_atr_unlock_bus, }; -static int i2c_atr_reserve_alias(struct i2c_atr *atr) +static int i2c_atr_reserve_alias(struct i2c_atr_alias_pool *alias_pool) { unsigned long idx; + u16 alias; - spin_lock(&atr->alias_mask_lock); + spin_lock(&alias_pool->lock); - idx = find_first_zero_bit(atr->alias_use_mask, atr->num_aliases); - if (idx >= atr->num_aliases) { - spin_unlock(&atr->alias_mask_lock); - dev_err(atr->dev, "failed to find a free alias\n"); + idx = find_first_zero_bit(alias_pool->use_mask, alias_pool->size); + if (idx >= alias_pool->size) { + spin_unlock(&alias_pool->lock); return -EBUSY; } - set_bit(idx, atr->alias_use_mask); + set_bit(idx, alias_pool->use_mask); - spin_unlock(&atr->alias_mask_lock); + alias = alias_pool->aliases[idx]; - return atr->aliases[idx]; + spin_unlock(&alias_pool->lock); + return alias; } -static void i2c_atr_release_alias(struct i2c_atr *atr, u16 alias) +static void i2c_atr_release_alias(struct i2c_atr_alias_pool *alias_pool, u16 alias) { unsigned int idx; - spin_lock(&atr->alias_mask_lock); + spin_lock(&alias_pool->lock); - for (idx = 0; idx < atr->num_aliases; ++idx) { - if (atr->aliases[idx] == alias) { - clear_bit(idx, atr->alias_use_mask); - spin_unlock(&atr->alias_mask_lock); + for (idx = 0; idx < alias_pool->size; ++idx) { + if (alias_pool->aliases[idx] == alias) { + clear_bit(idx, alias_pool->use_mask); + spin_unlock(&alias_pool->lock); return; } } - spin_unlock(&atr->alias_mask_lock); - - /* This should never happen */ - dev_warn(atr->dev, "Unable to find mapped alias\n"); + spin_unlock(&alias_pool->lock); } static int i2c_atr_attach_addr(struct i2c_adapter *adapter, @@ -308,9 +357,11 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, u16 alias; int ret; - ret = i2c_atr_reserve_alias(atr); - if (ret < 0) + ret = i2c_atr_reserve_alias(atr->alias_pool); + if (ret < 0) { + dev_err(atr->dev, "failed to find a free alias\n"); return ret; + } alias = ret; @@ -336,7 +387,7 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, err_free: kfree(c2a); err_release_alias: - i2c_atr_release_alias(atr, alias); + i2c_atr_release_alias(atr->alias_pool, alias); return ret; } @@ -357,7 +408,7 @@ static void i2c_atr_detach_addr(struct i2c_adapter *adapter, return; } - i2c_atr_release_alias(atr, c2a->alias); + i2c_atr_release_alias(atr->alias_pool, c2a->alias); dev_dbg(atr->dev, "chan%u: addr 0x%02x unmapped from alias 0x%02x\n", @@ -411,12 +462,11 @@ static int i2c_atr_bus_notifier_call(struct notifier_block *nb, static int i2c_atr_parse_alias_pool(struct i2c_atr *atr) { + struct i2c_atr_alias_pool *alias_pool; struct device *dev = atr->dev; - unsigned long *alias_use_mask; size_t num_aliases; unsigned int i; u32 *aliases32; - u16 *aliases16; int ret; ret = fwnode_property_count_u32(dev_fwnode(dev), "i2c-alias-pool"); @@ -428,12 +478,23 @@ static int i2c_atr_parse_alias_pool(struct i2c_atr *atr) num_aliases = ret; - if (!num_aliases) + alias_pool = i2c_atr_alloc_alias_pool(num_aliases); + if (IS_ERR(alias_pool)) { + ret = PTR_ERR(alias_pool); + dev_err(dev, "Failed to allocate alias pool, err %d\n", ret); + return ret; + } + + atr->alias_pool = alias_pool; + + if (!alias_pool->size) return 0; aliases32 = kcalloc(num_aliases, sizeof(*aliases32), GFP_KERNEL); - if (!aliases32) - return -ENOMEM; + if (!aliases32) { + ret = -ENOMEM; + goto err_free_alias_pool; + } ret = fwnode_property_read_u32_array(dev_fwnode(dev), "i2c-alias-pool", aliases32, num_aliases); @@ -443,43 +504,27 @@ static int i2c_atr_parse_alias_pool(struct i2c_atr *atr) goto err_free_aliases32; } - aliases16 = kcalloc(num_aliases, sizeof(*aliases16), GFP_KERNEL); - if (!aliases16) { - ret = -ENOMEM; - goto err_free_aliases32; - } - for (i = 0; i < num_aliases; i++) { if (!(aliases32[i] & 0xffff0000)) { - aliases16[i] = aliases32[i]; + alias_pool->aliases[i] = aliases32[i]; continue; } dev_err(dev, "Failed to parse 'i2c-alias-pool' property: I2C flags are not supported\n"); ret = -EINVAL; - goto err_free_aliases16; - } - - alias_use_mask = bitmap_zalloc(num_aliases, GFP_KERNEL); - if (!alias_use_mask) { - ret = -ENOMEM; - goto err_free_aliases16; + goto err_free_aliases32; } kfree(aliases32); - atr->num_aliases = num_aliases; - atr->aliases = aliases16; - atr->alias_use_mask = alias_use_mask; - - dev_dbg(dev, "i2c-alias-pool has %zu aliases", atr->num_aliases); + dev_dbg(dev, "i2c-alias-pool has %zu aliases", alias_pool->size); return 0; -err_free_aliases16: - kfree(aliases16); err_free_aliases32: kfree(aliases32); +err_free_alias_pool: + i2c_atr_free_alias_pool(alias_pool); return ret; } @@ -500,7 +545,6 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, return ERR_PTR(-ENOMEM); mutex_init(&atr->lock); - spin_lock_init(&atr->alias_mask_lock); atr->parent = parent; atr->dev = dev; @@ -520,13 +564,12 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, atr->i2c_nb.notifier_call = i2c_atr_bus_notifier_call; ret = bus_register_notifier(&i2c_bus_type, &atr->i2c_nb); if (ret) - goto err_free_aliases; + goto err_free_alias_pool; return atr; -err_free_aliases: - bitmap_free(atr->alias_use_mask); - kfree(atr->aliases); +err_free_alias_pool: + i2c_atr_free_alias_pool(atr->alias_pool); err_destroy_mutex: mutex_destroy(&atr->lock); kfree(atr); @@ -543,8 +586,7 @@ void i2c_atr_delete(struct i2c_atr *atr) WARN_ON(atr->adapter[i]); bus_unregister_notifier(&i2c_bus_type, &atr->i2c_nb); - bitmap_free(atr->alias_use_mask); - kfree(atr->aliases); + i2c_atr_free_alias_pool(atr->alias_pool); mutex_destroy(&atr->lock); kfree(atr); } From patchwork Fri Nov 8 15:36:58 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 842212 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CB00D21C180; 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arc=none smtp.client-ip=217.70.183.200 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="a1PqIS7m" Received: by mail.gandi.net (Postfix) with ESMTPSA id 4B9B120013; Fri, 8 Nov 2024 15:37:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731080234; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iJgfCjnvNvvTwyd/QBAk+QnMdb9ttUUXMA4mNlEtL4o=; b=a1PqIS7mPvwcDqHrlP2l1iMSJciWUUFBQyu5tCqQOsPge2mPlU1qHfBbXa2rEsQKNGYCBi PW1I6J6i79fmbqT5hNepb8YWARbivT1l2G7ZkQsO4VOtj01UJc2RCq9VyadPJEygKxiuKv mOk7BLtUH3JesEMRVCLUkpT8tdSXfygGGhQkv3Za/fKpOjW6HKVyMRr3XGKQKdFqWbgk7u q5LL6QTZr13hToDqv0t1lzqMmiT6DTHX23wLELp6BqPVdsdvGjhN5ISJ3nZrjewWhm5Hpu R13Ug+zLMAPUR9a6q28mpRVmZ4u1Wv9xV1s+m1XCDZENILGU97KdyboC/5PSAQ== From: Romain Gantois Date: Fri, 08 Nov 2024 16:36:58 +0100 Subject: [PATCH 6/9] i2c: rename field 'alias_list' of struct i2c_atr_chan to 'alias_pairs' Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241108-fpc202-v1-6-fe42c698bc92@bootlin.com> References: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> In-Reply-To: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com The "alias_list" field of struct i2c_atr_chan describes translation table entries programmed in the ATR channel. This terminology will become more confusing when per-channel alias pool support is introduced, as struct i2c_atr_chan will gain a new field called "alias_pool", which will describe aliases which are available to the ATR channel. Rename the "alias_list" field to "alias_pairs" to clearly distinguish it from the future "alias_pool" field. No functional change is intended. Signed-off-by: Romain Gantois --- drivers/i2c/i2c-atr.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c index c873fe52288175151040a4c32e6ed07735586004..84d82c09708ae39cf5501a1fb67e8f2af2bb5446 100644 --- a/drivers/i2c/i2c-atr.c +++ b/drivers/i2c/i2c-atr.c @@ -56,7 +56,7 @@ struct i2c_atr_alias_pool { * @adap: The &struct i2c_adapter for the channel * @atr: The parent I2C ATR * @chan_id: The ID of this channel - * @alias_list: List of @struct i2c_atr_alias_pair containing the + * @alias_pairs: List of @struct i2c_atr_alias_pair containing the * assigned aliases * @orig_addrs_lock: Mutex protecting @orig_addrs * @orig_addrs: Buffer used to store the original addresses during transmit @@ -67,7 +67,7 @@ struct i2c_atr_chan { struct i2c_atr *atr; u32 chan_id; - struct list_head alias_list; + struct list_head alias_pairs; /* Lock orig_addrs during xfer */ struct mutex orig_addrs_lock; @@ -192,7 +192,7 @@ static int i2c_atr_map_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs, for (i = 0; i < num; i++) { chan->orig_addrs[i] = msgs[i].addr; - c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, + c2a = i2c_atr_find_mapping_by_addr(&chan->alias_pairs, msgs[i].addr); if (!c2a) { dev_err(atr->dev, "client 0x%02x not mapped!\n", @@ -262,7 +262,7 @@ static int i2c_atr_smbus_xfer(struct i2c_adapter *adap, u16 addr, struct i2c_adapter *parent = atr->parent; struct i2c_atr_alias_pair *c2a; - c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, addr); + c2a = i2c_atr_find_mapping_by_addr(&chan->alias_pairs, addr); if (!c2a) { dev_err(atr->dev, "client 0x%02x not mapped!\n", addr); return -ENXIO; @@ -380,7 +380,7 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, c2a->addr = addr; c2a->alias = alias; - list_add(&c2a->node, &chan->alias_list); + list_add(&c2a->node, &chan->alias_pairs); return 0; @@ -401,7 +401,7 @@ static void i2c_atr_detach_addr(struct i2c_adapter *adapter, atr->ops->detach_addr(atr, chan->chan_id, addr); - c2a = i2c_atr_find_mapping_by_addr(&chan->alias_list, addr); + c2a = i2c_atr_find_mapping_by_addr(&chan->alias_pairs, addr); if (!c2a) { /* This should never happen */ dev_warn(atr->dev, "Unable to find address mapping\n"); @@ -621,7 +621,7 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, chan->atr = atr; chan->chan_id = chan_id; - INIT_LIST_HEAD(&chan->alias_list); + INIT_LIST_HEAD(&chan->alias_pairs); mutex_init(&chan->orig_addrs_lock); snprintf(chan->adap.name, sizeof(chan->adap.name), "i2c-%d-atr-%d", From patchwork Fri Nov 8 15:36:59 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 842211 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C3EAF21A6FE; Fri, 8 Nov 2024 15:37:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.200 ARC-Seal: i=1; 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dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="o3PEA3mV" Received: by mail.gandi.net (Postfix) with ESMTPSA id 6393F20008; Fri, 8 Nov 2024 15:37:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731080235; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=SjvACWeOBtIlxQ+9E7kITjN5s4TisAetZ11z5E/CII4=; b=o3PEA3mVhEQ33gwsPq/KIcmo4joScbhHDSKwknNyTOf0zX616jJ1IQU/DYLtWGH0YLQMI3 3ZmgL9WGJikLj5TARsZLT5t6xkIy12LrVj2K4KpUHuMbXjOXMkTrucZu6AysrtV0vI6bzg Qp8JXZACsJFEyz4jl4O/CMEpMQ2Xz4ylElyQ5/vDEgzGi0IQs6G5nmrk2uCiIuRVpEtOKs QvB5P6fTfZWewPZB525Y5LOQNIIwT5E45NOf1ByFL0kE9aDqtrdFSlZRqJRGPFVsnw6QJ0 rIwn5EGvb3TxdKPDo74AkLXROAm6ic41IWnWhDaDIrK27TVgu/5gIHpDvIRyZQ== From: Romain Gantois Date: Fri, 08 Nov 2024 16:36:59 +0100 Subject: [PATCH 7/9] i2c: support per-channel ATR alias pools Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241108-fpc202-v1-7-fe42c698bc92@bootlin.com> References: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> In-Reply-To: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com Some I2C address translators (ATRs) assign each of their remote peripheral aliases to a specific channel. To properly handle these devices, add support for having separate alias pools for each ATR channel. This is achieved by allowing callers of i2c_atr_add_adapter to pass an optional alias list. If present, this list will be used to populate the channel's alias pool. Otherwise, the common alias pool will be used. Signed-off-by: Romain Gantois --- drivers/i2c/i2c-atr.c | 68 ++++++++++++++++++++++++++++++------------- drivers/media/i2c/ds90ub913.c | 9 ++++-- drivers/media/i2c/ds90ub953.c | 9 ++++-- include/linux/i2c-atr.h | 34 ++++++++++++++++------ 4 files changed, 87 insertions(+), 33 deletions(-) diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c index 84d82c09708ae39cf5501a1fb67e8f2af2bb5446..f7c4d39ad3b48ad64be25b8462394e569aee57d4 100644 --- a/drivers/i2c/i2c-atr.c +++ b/drivers/i2c/i2c-atr.c @@ -37,6 +37,7 @@ struct i2c_atr_alias_pair { /** * struct i2c_atr_alias_pool - Pool of client aliases available for an ATR. * @size: Total number of aliases + * @shared: Indicates if this alias pool is shared by multiple channels * * @lock: Lock protecting @aliases and @use_mask * @aliases: Array of aliases, must hold exactly @size elements @@ -44,6 +45,7 @@ struct i2c_atr_alias_pair { */ struct i2c_atr_alias_pool { size_t size; + bool shared; /* Protects aliases and use_mask */ spinlock_t lock; @@ -58,6 +60,8 @@ struct i2c_atr_alias_pool { * @chan_id: The ID of this channel * @alias_pairs: List of @struct i2c_atr_alias_pair containing the * assigned aliases + * @alias_pool: Pool of available client aliases + * * @orig_addrs_lock: Mutex protecting @orig_addrs * @orig_addrs: Buffer used to store the original addresses during transmit * @orig_addrs_size: Size of @orig_addrs @@ -68,6 +72,7 @@ struct i2c_atr_chan { u32 chan_id; struct list_head alias_pairs; + struct i2c_atr_alias_pool *alias_pool; /* Lock orig_addrs during xfer */ struct mutex orig_addrs_lock; @@ -84,7 +89,7 @@ struct i2c_atr_chan { * @algo: The &struct i2c_algorithm for adapters * @lock: Lock for the I2C bus segment (see &struct i2c_lock_operations) * @max_adapters: Maximum number of adapters this I2C ATR can have - * @alias_pool: Pool of available client aliases + * @alias_pool: Optional common pool of available client aliases * @i2c_nb: Notifier for remote client add & del events * @adapter: Array of adapters */ @@ -357,7 +362,7 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, u16 alias; int ret; - ret = i2c_atr_reserve_alias(atr->alias_pool); + ret = i2c_atr_reserve_alias(chan->alias_pool); if (ret < 0) { dev_err(atr->dev, "failed to find a free alias\n"); return ret; @@ -387,7 +392,7 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, err_free: kfree(c2a); err_release_alias: - i2c_atr_release_alias(atr->alias_pool, alias); + i2c_atr_release_alias(chan->alias_pool, alias); return ret; } @@ -408,7 +413,7 @@ static void i2c_atr_detach_addr(struct i2c_adapter *adapter, return; } - i2c_atr_release_alias(atr->alias_pool, c2a->alias); + i2c_atr_release_alias(chan->alias_pool, c2a->alias); dev_dbg(atr->dev, "chan%u: addr 0x%02x unmapped from alias 0x%02x\n", @@ -469,14 +474,18 @@ static int i2c_atr_parse_alias_pool(struct i2c_atr *atr) u32 *aliases32; int ret; - ret = fwnode_property_count_u32(dev_fwnode(dev), "i2c-alias-pool"); - if (ret < 0) { - dev_err(dev, "Failed to count 'i2c-alias-pool' property: %d\n", - ret); - return ret; - } + if (!fwnode_property_present(dev_fwnode(dev), "i2c-alias-pool")) { + num_aliases = 0; + } else { + ret = fwnode_property_count_u32(dev_fwnode(dev), "i2c-alias-pool"); + if (ret < 0) { + dev_err(dev, "Failed to count 'i2c-alias-pool' property: %d\n", + ret); + return ret; + } - num_aliases = ret; + num_aliases = ret; + } alias_pool = i2c_atr_alloc_alias_pool(num_aliases); if (IS_ERR(alias_pool)) { @@ -592,15 +601,15 @@ void i2c_atr_delete(struct i2c_atr *atr) } EXPORT_SYMBOL_NS_GPL(i2c_atr_delete, I2C_ATR); -int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, - struct device *adapter_parent, - struct fwnode_handle *bus_handle) +int i2c_atr_add_adapter(struct i2c_atr *atr, struct i2c_atr_adap_desc *desc) { + struct fwnode_handle *bus_handle = desc->bus_handle; struct i2c_adapter *parent = atr->parent; + char symlink_name[ATR_MAX_SYMLINK_LEN]; struct device *dev = atr->dev; + u32 chan_id = desc->chan_id; struct i2c_atr_chan *chan; - char symlink_name[ATR_MAX_SYMLINK_LEN]; - int ret; + int ret, idx; if (chan_id >= atr->max_adapters) { dev_err(dev, "No room for more i2c-atr adapters\n"); @@ -616,8 +625,8 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, if (!chan) return -ENOMEM; - if (!adapter_parent) - adapter_parent = dev; + if (!desc->parent) + desc->parent = dev; chan->atr = atr; chan->chan_id = chan_id; @@ -629,7 +638,7 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, chan->adap.owner = THIS_MODULE; chan->adap.algo = &atr->algo; chan->adap.algo_data = chan; - chan->adap.dev.parent = adapter_parent; + chan->adap.dev.parent = desc->parent; chan->adap.retries = parent->retries; chan->adap.timeout = parent->timeout; chan->adap.quirks = parent->quirks; @@ -656,13 +665,26 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, fwnode_handle_put(atr_node); } + if (desc->num_aliases > 0) { + chan->alias_pool = i2c_atr_alloc_alias_pool(desc->num_aliases); + if (IS_ERR(chan->alias_pool)) { + ret = PTR_ERR(chan->alias_pool); + goto err_fwnode_put; + } + + for (idx = 0; idx < desc->num_aliases; idx++) + chan->alias_pool->aliases[idx] = desc->aliases[idx]; + } else { + chan->alias_pool = atr->alias_pool; + } + atr->adapter[chan_id] = &chan->adap; ret = i2c_add_adapter(&chan->adap); if (ret) { dev_err(dev, "failed to add atr-adapter %u (error=%d)\n", chan_id, ret); - goto err_fwnode_put; + goto err_free_alias_pool; } snprintf(symlink_name, sizeof(symlink_name), "channel-%u", @@ -679,6 +701,9 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, return 0; +err_free_alias_pool: + if (!chan->alias_pool->shared) + i2c_atr_free_alias_pool(chan->alias_pool); err_fwnode_put: fwnode_handle_put(dev_fwnode(&chan->adap.dev)); mutex_destroy(&chan->orig_addrs_lock); @@ -711,6 +736,9 @@ void i2c_atr_del_adapter(struct i2c_atr *atr, u32 chan_id) i2c_del_adapter(adap); + if (!chan->alias_pool->shared) + i2c_atr_free_alias_pool(chan->alias_pool); + atr->adapter[chan_id] = NULL; fwnode_handle_put(fwnode); diff --git a/drivers/media/i2c/ds90ub913.c b/drivers/media/i2c/ds90ub913.c index 8eed4a200fd89b5af1fc4578cb865bf1408acd76..1bb4efa44ede1267e15d29e0ce3965372bf3bb89 100644 --- a/drivers/media/i2c/ds90ub913.c +++ b/drivers/media/i2c/ds90ub913.c @@ -656,6 +656,7 @@ static int ub913_i2c_master_init(struct ub913_data *priv) static int ub913_add_i2c_adapter(struct ub913_data *priv) { struct device *dev = &priv->client->dev; + struct i2c_atr_adap_desc desc = { }; struct fwnode_handle *i2c_handle; int ret; @@ -663,8 +664,12 @@ static int ub913_add_i2c_adapter(struct ub913_data *priv) if (!i2c_handle) return 0; - ret = i2c_atr_add_adapter(priv->plat_data->atr, priv->plat_data->port, - dev, i2c_handle); + desc.chan_id = priv->plat_data->port; + desc.parent = dev; + desc.bus_handle = i2c_handle; + desc.num_aliases = 0; + + ret = i2c_atr_add_adapter(priv->plat_data->atr, &desc); fwnode_handle_put(i2c_handle); diff --git a/drivers/media/i2c/ds90ub953.c b/drivers/media/i2c/ds90ub953.c index 16f88db1498162cb795b1dcbe45bff90dd8ce431..e7cdb5d07a0378eab7aeeba36afdec319565c110 100644 --- a/drivers/media/i2c/ds90ub953.c +++ b/drivers/media/i2c/ds90ub953.c @@ -1103,6 +1103,7 @@ static int ub953_register_clkout(struct ub953_data *priv) static int ub953_add_i2c_adapter(struct ub953_data *priv) { struct device *dev = &priv->client->dev; + struct i2c_atr_adap_desc desc = { }; struct fwnode_handle *i2c_handle; int ret; @@ -1110,8 +1111,12 @@ static int ub953_add_i2c_adapter(struct ub953_data *priv) if (!i2c_handle) return 0; - ret = i2c_atr_add_adapter(priv->plat_data->atr, priv->plat_data->port, - dev, i2c_handle); + desc.chan_id = priv->plat_data->port; + desc.parent = dev; + desc.bus_handle = i2c_handle; + desc.num_aliases = 0; + + ret = i2c_atr_add_adapter(priv->plat_data->atr, &desc); fwnode_handle_put(i2c_handle); diff --git a/include/linux/i2c-atr.h b/include/linux/i2c-atr.h index 14c1f9175c0db6a8a9c6ef5d771ae68361132a76..1c3a5bcd939fc56f4a6ca1b6a5cc0ac2c17083b7 100644 --- a/include/linux/i2c-atr.h +++ b/include/linux/i2c-atr.h @@ -36,6 +36,29 @@ struct i2c_atr_ops { u16 addr); }; +/** + * struct i2c_atr_adap_desc - An ATR downstream bus descriptor + * @chan_id: Index of the new adapter (0 .. max_adapters-1). This value is + * passed to the callbacks in `struct i2c_atr_ops`. + * @parent: The device used as the parent of the new i2c adapter, or NULL + * to use the i2c-atr device as the parent. + * @bus_handle: The fwnode handle that points to the adapter's i2c + * peripherals, or NULL. + * @num_aliases: The number of aliases in this adapter's private alias pool. Set + * to zero if this adapter uses the ATR's global alias pool. + * @aliases: An optional array of private aliases used by the adapter + * instead of the ATR's global pool of aliases. Must contain + * exactly num_aliases entries if num_aliases > 0, is ignored + * otherwise. + */ +struct i2c_atr_adap_desc { + u32 chan_id; + struct device *parent; + struct fwnode_handle *bus_handle; + size_t num_aliases; + u16 *aliases; +}; + /** * i2c_atr_new() - Allocate and initialize an I2C ATR helper. * @parent: The parent (upstream) adapter @@ -65,12 +88,7 @@ void i2c_atr_delete(struct i2c_atr *atr); /** * i2c_atr_add_adapter - Create a child ("downstream") I2C bus. * @atr: The I2C ATR - * @chan_id: Index of the new adapter (0 .. max_adapters-1). This value is - * passed to the callbacks in `struct i2c_atr_ops`. - * @adapter_parent: The device used as the parent of the new i2c adapter, or NULL - * to use the i2c-atr device as the parent. - * @bus_handle: The fwnode handle that points to the adapter's i2c - * peripherals, or NULL. + * @desc: An ATR adapter descriptor * * After calling this function a new i2c bus will appear. Adding and removing * devices on the downstream bus will result in calls to the @@ -85,9 +103,7 @@ void i2c_atr_delete(struct i2c_atr *atr); * * Return: 0 on success, a negative error code otherwise. */ -int i2c_atr_add_adapter(struct i2c_atr *atr, u32 chan_id, - struct device *adapter_parent, - struct fwnode_handle *bus_handle); +int i2c_atr_add_adapter(struct i2c_atr *atr, struct i2c_atr_adap_desc *desc); /** * i2c_atr_del_adapter - Remove a child ("downstream") I2C bus added by From patchwork Fri Nov 8 15:37:00 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 841831 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BBE6121F4D3; Fri, 8 Nov 2024 15:37:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.200 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731080240; cv=none; b=U21M55XacDzSN+FylZ6mooI6wh3T3jAMFCzqXS6A35Pz1IUlvmrkRA6QB2ThfASAfGsffBvle2djHmfSlPwIBJrADr2HbZfTgt8VQC8WqWHn8U0i1MyhdBiztJN3LLYhCNFgmzVub5CaTXKVLJEVg+VkvV++emc/np4pn/Cs9+c= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731080240; c=relaxed/simple; bh=z3pkah0+TmODuiRyVMMs8EvN63Piux7wYFnD0hJmd70=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=saWiKw1svu/BNjmCxhyJVii7fdK3RfUGe3gB48r1q3rRtj6oz8i4k5IZUPBvZdRUNPbnfhGhKlZxuZg8tqfHRMWQQZ29BPrMHF7DF+pexiiGdoyR8GtQL3rwNImfiJ88Pn7UKKfDKXueJYoqzadbbnxztVKm6tqN6ZY4yUJitfA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=eGxXfhEY; arc=none smtp.client-ip=217.70.183.200 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="eGxXfhEY" Received: by mail.gandi.net (Postfix) with ESMTPSA id 5C14920002; Fri, 8 Nov 2024 15:37:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731080236; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iIJ4d3CEfY6cAlBF9W/fqRPK2MRoB0LfBP4W5Cd+slU=; b=eGxXfhEYl+LGgqdhUqQdXiDnkS/WXYr3z9w8T2ozKAsDU9kfRQoZrTDzy/bytWvI66dtXX 3SA7pcdqc3pjyxxtU3zy9ogT9MYZG7EIdGSOMvYqrF7qm7+l3JPJ3CvfcYcC6wNisfR8+u 6/kjxlfUBU7kSt2jEQbPr9uVzADpbDroPXc1Hcwgk9X0Ibqm1V+l7zZsefRidfMTvtx1ae o7zOZ7THBxzcozyFMQmeUGtZphehehFpQFusJx9tRrMeehGER6GHM88InZ7Q8GVp6ltvFT Bt6BCgm6MC2zLZSwWGUSX/QsJb9QHi2kz48Fl5G4zKsXtqI1VNPGHN6YBrBEeg== From: Romain Gantois Date: Fri, 08 Nov 2024 16:37:00 +0100 Subject: [PATCH 8/9] i2c: Support dynamic address translation Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241108-fpc202-v1-8-fe42c698bc92@bootlin.com> References: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> In-Reply-To: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com The i2c-atr module keeps a list of associations between I2C client aliases and I2C addresses. This represents the address translation table which is programmed into an ATR channel at any given time. This list is only updated when a new client is bound to the channel. However in some cases, an ATR channel can have more downstream clients than available aliases. One example of this is an SFP module that is bound to an FPC202 port. The FPC202 port can only access up to two logical I2C addresses. However, the SFP module may expose up to three logical I2C addresses: its EEPROM on 7-bit addresses 0x50 and 0x51, and a PHY transceiver on address 0x56. In cases like these, it is necessary to reconfigure the channel's translation table on the fly, so that all three I2C addresses can be accessed when needed. Add an optional "dynamic_c2a" flag to the i2c-atr module which allows it to provide on-the-fly address translation. This is achieved by modifying an ATR channel's translation table whenever an I2C transaction with unmapped clients is requested. Add a mutex to protect alias_list. This prevents i2c_atr_dynamic_attach/detach_addr from racing with the bus notifier handler to modify alias_list. Signed-off-by: Romain Gantois --- drivers/i2c/i2c-atr.c | 244 ++++++++++++++++++++++++++++++++---------- drivers/media/i2c/ds90ub960.c | 2 +- include/linux/i2c-atr.h | 13 ++- 3 files changed, 202 insertions(+), 57 deletions(-) diff --git a/drivers/i2c/i2c-atr.c b/drivers/i2c/i2c-atr.c index f7c4d39ad3b48ad64be25b8462394e569aee57d4..cc9ef19078b43ed57f876b0a132ecf979df54730 100644 --- a/drivers/i2c/i2c-atr.c +++ b/drivers/i2c/i2c-atr.c @@ -16,6 +16,7 @@ #include #include #include +#include #define ATR_MAX_ADAPTERS 100 /* Just a sanity limit */ #define ATR_MAX_SYMLINK_LEN 11 /* Longest name is 10 chars: "channel-99" */ @@ -27,9 +28,17 @@ * @alias: I2C alias address assigned by the driver. * This is the address that will be used to issue I2C transactions * on the parent (physical) bus. + * @fixed: Alias pair cannot be replaced during dynamic address attachment. + * This flag is necessary for situations where a single I2C transaction + * contains more distinct target addresses than the ATR channel can handle. + * It marks addresses that have already been attached to an alias so + * that their alias pair is not evicted by a subsequent address in the same + * transaction. + * */ struct i2c_atr_alias_pair { struct list_head node; + bool fixed; u16 addr; u16 alias; }; @@ -58,6 +67,7 @@ struct i2c_atr_alias_pool { * @adap: The &struct i2c_adapter for the channel * @atr: The parent I2C ATR * @chan_id: The ID of this channel + * @alias_pairs_lock: Mutex protecting @alias_pairs * @alias_pairs: List of @struct i2c_atr_alias_pair containing the * assigned aliases * @alias_pool: Pool of available client aliases @@ -71,6 +81,8 @@ struct i2c_atr_chan { struct i2c_atr *atr; u32 chan_id; + /* Lock alias_pairs during attach/detach */ + struct mutex alias_pairs_lock; struct list_head alias_pairs; struct i2c_atr_alias_pool *alias_pool; @@ -89,6 +101,7 @@ struct i2c_atr_chan { * @algo: The &struct i2c_algorithm for adapters * @lock: Lock for the I2C bus segment (see &struct i2c_lock_operations) * @max_adapters: Maximum number of adapters this I2C ATR can have + * @flags: Optional features associated with this ATR * @alias_pool: Optional common pool of available client aliases * @i2c_nb: Notifier for remote client add & del events * @adapter: Array of adapters @@ -104,6 +117,7 @@ struct i2c_atr { /* lock for the I2C bus segment (see struct i2c_lock_operations) */ struct mutex lock; int max_adapters; + unsigned short flags; struct i2c_atr_alias_pool *alias_pool; @@ -153,16 +167,128 @@ static void i2c_atr_free_alias_pool(struct i2c_atr_alias_pool *alias_pool) kfree(alias_pool); } +/* Must be called with alias_pairs_lock held */ +static struct i2c_atr_alias_pair *i2c_atr_create_c2a(struct i2c_atr_chan *chan, + u16 alias, u16 addr) +{ + struct i2c_atr_alias_pair *c2a; + + lockdep_assert_held(&chan->alias_pairs_lock); + + c2a = kzalloc(sizeof(*c2a), GFP_KERNEL); + if (!c2a) + return NULL; + + c2a->addr = addr; + c2a->alias = alias; + + list_add(&c2a->node, &chan->alias_pairs); + + return c2a; +} + +static int i2c_atr_reserve_alias(struct i2c_atr_alias_pool *alias_pool) +{ + unsigned long idx; + u16 alias; + + spin_lock(&alias_pool->lock); + + idx = find_first_zero_bit(alias_pool->use_mask, alias_pool->size); + if (idx >= alias_pool->size) { + spin_unlock(&alias_pool->lock); + return -EBUSY; + } + + set_bit(idx, alias_pool->use_mask); + + alias = alias_pool->aliases[idx]; + + spin_unlock(&alias_pool->lock); + return alias; +} + +static void i2c_atr_release_alias(struct i2c_atr_alias_pool *alias_pool, u16 alias) +{ + unsigned int idx; + + spin_lock(&alias_pool->lock); + + for (idx = 0; idx < alias_pool->size; ++idx) { + if (alias_pool->aliases[idx] == alias) { + clear_bit(idx, alias_pool->use_mask); + spin_unlock(&alias_pool->lock); + return; + } + } + + spin_unlock(&alias_pool->lock); +} + +/* Must be called with alias_pairs_lock held */ static struct i2c_atr_alias_pair * -i2c_atr_find_mapping_by_addr(const struct list_head *list, u16 phys_addr) +i2c_atr_find_mapping_by_addr(struct i2c_atr_chan *chan, u16 addr) { + struct i2c_atr *atr = chan->atr; struct i2c_atr_alias_pair *c2a; + struct list_head *alias_pairs; + u16 alias; + int ret; + + lockdep_assert_held(&chan->alias_pairs_lock); - list_for_each_entry(c2a, list, node) { - if (c2a->addr == phys_addr) + alias_pairs = &chan->alias_pairs; + + list_for_each_entry(c2a, alias_pairs, node) { + if (c2a->addr == addr) return c2a; } + if (!(atr->flags & I2C_ATR_FLAG_DYNAMIC_C2A)) + return NULL; + + ret = i2c_atr_reserve_alias(chan->alias_pool); + if (ret < 0) { + // If no free aliases are left, replace an existing one + if (unlikely(list_empty(alias_pairs))) + return NULL; + + list_for_each_entry_reverse(c2a, alias_pairs, node) + if (!c2a->fixed) + break; + + if (c2a->fixed) + return NULL; + + atr->ops->detach_addr(atr, chan->chan_id, c2a->addr); + c2a->addr = addr; + + // Move updated entry to beginning of list + list_move(&c2a->node, alias_pairs); + + alias = c2a->alias; + } else { + alias = ret; + + c2a = i2c_atr_create_c2a(chan, alias, addr); + if (!c2a) + goto err_release_alias; + } + + ret = atr->ops->attach_addr(atr, chan->chan_id, c2a->addr, c2a->alias); + if (ret) { + dev_err(atr->dev, "failed to attach 0x%02x on channel %d: err %d\n", + addr, chan->chan_id, ret); + goto err_del_c2a; + } + + return c2a; + +err_del_c2a: + list_del(&c2a->node); + kfree(c2a); +err_release_alias: + i2c_atr_release_alias(chan->alias_pool, alias); return NULL; } @@ -178,7 +304,7 @@ static int i2c_atr_map_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs, { struct i2c_atr *atr = chan->atr; static struct i2c_atr_alias_pair *c2a; - int i; + int i, ret = 0; /* Ensure we have enough room to save the original addresses */ if (unlikely(chan->orig_addrs_size < num)) { @@ -194,11 +320,13 @@ static int i2c_atr_map_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs, chan->orig_addrs_size = num; } + mutex_lock(&chan->alias_pairs_lock); + for (i = 0; i < num; i++) { chan->orig_addrs[i] = msgs[i].addr; - c2a = i2c_atr_find_mapping_by_addr(&chan->alias_pairs, - msgs[i].addr); + c2a = i2c_atr_find_mapping_by_addr(chan, msgs[i].addr); + if (!c2a) { dev_err(atr->dev, "client 0x%02x not mapped!\n", msgs[i].addr); @@ -206,13 +334,19 @@ static int i2c_atr_map_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs, while (i--) msgs[i].addr = chan->orig_addrs[i]; - return -ENXIO; + ret = -ENXIO; + goto out_unlock; } + // Prevent c2a from being overwritten by another client in this transaction + c2a->fixed = true; + msgs[i].addr = c2a->alias; } - return 0; +out_unlock: + mutex_unlock(&chan->alias_pairs_lock); + return ret; } /* @@ -225,10 +359,24 @@ static int i2c_atr_map_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs, static void i2c_atr_unmap_msgs(struct i2c_atr_chan *chan, struct i2c_msg *msgs, int num) { + struct i2c_atr_alias_pair *c2a; int i; for (i = 0; i < num; i++) msgs[i].addr = chan->orig_addrs[i]; + + mutex_lock(&chan->alias_pairs_lock); + + if (unlikely(list_empty(&chan->alias_pairs))) + goto out_unlock; + + // unfix c2a entries so that subsequent transfers can reuse their aliases + list_for_each_entry(c2a, &chan->alias_pairs, node) { + c2a->fixed = false; + } + +out_unlock: + mutex_unlock(&chan->alias_pairs_lock); } static int i2c_atr_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, @@ -266,14 +414,23 @@ static int i2c_atr_smbus_xfer(struct i2c_adapter *adap, u16 addr, struct i2c_atr *atr = chan->atr; struct i2c_adapter *parent = atr->parent; struct i2c_atr_alias_pair *c2a; + u16 alias; + + mutex_lock(&chan->alias_pairs_lock); + + c2a = i2c_atr_find_mapping_by_addr(chan, addr); - c2a = i2c_atr_find_mapping_by_addr(&chan->alias_pairs, addr); if (!c2a) { dev_err(atr->dev, "client 0x%02x not mapped!\n", addr); + mutex_unlock(&chan->alias_pairs_lock); return -ENXIO; } - return i2c_smbus_xfer(parent, c2a->alias, flags, read_write, command, + alias = c2a->alias; + + mutex_unlock(&chan->alias_pairs_lock); + + return i2c_smbus_xfer(parent, alias, flags, read_write, command, size, data); } @@ -315,44 +472,6 @@ static const struct i2c_lock_operations i2c_atr_lock_ops = { .unlock_bus = i2c_atr_unlock_bus, }; -static int i2c_atr_reserve_alias(struct i2c_atr_alias_pool *alias_pool) -{ - unsigned long idx; - u16 alias; - - spin_lock(&alias_pool->lock); - - idx = find_first_zero_bit(alias_pool->use_mask, alias_pool->size); - if (idx >= alias_pool->size) { - spin_unlock(&alias_pool->lock); - return -EBUSY; - } - - set_bit(idx, alias_pool->use_mask); - - alias = alias_pool->aliases[idx]; - - spin_unlock(&alias_pool->lock); - return alias; -} - -static void i2c_atr_release_alias(struct i2c_atr_alias_pool *alias_pool, u16 alias) -{ - unsigned int idx; - - spin_lock(&alias_pool->lock); - - for (idx = 0; idx < alias_pool->size; ++idx) { - if (alias_pool->aliases[idx] == alias) { - clear_bit(idx, alias_pool->use_mask); - spin_unlock(&alias_pool->lock); - return; - } - } - - spin_unlock(&alias_pool->lock); -} - static int i2c_atr_attach_addr(struct i2c_adapter *adapter, u16 addr) { @@ -370,7 +489,9 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, alias = ret; - c2a = kzalloc(sizeof(*c2a), GFP_KERNEL); + mutex_lock(&chan->alias_pairs_lock); + + c2a = i2c_atr_create_c2a(chan, alias, addr); if (!c2a) { ret = -ENOMEM; goto err_release_alias; @@ -378,7 +499,7 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, ret = atr->ops->attach_addr(atr, chan->chan_id, addr, alias); if (ret) - goto err_free; + goto err_del_c2a; dev_dbg(atr->dev, "chan%u: addr 0x%02x mapped at alias 0x%02x\n", chan->chan_id, addr, alias); @@ -387,13 +508,16 @@ static int i2c_atr_attach_addr(struct i2c_adapter *adapter, c2a->alias = alias; list_add(&c2a->node, &chan->alias_pairs); - return 0; + goto out_unlock; -err_free: +err_del_c2a: + list_del(&c2a->node); kfree(c2a); + c2a = NULL; err_release_alias: i2c_atr_release_alias(chan->alias_pool, alias); - +out_unlock: + mutex_unlock(&chan->alias_pairs_lock); return ret; } @@ -406,13 +530,18 @@ static void i2c_atr_detach_addr(struct i2c_adapter *adapter, atr->ops->detach_addr(atr, chan->chan_id, addr); - c2a = i2c_atr_find_mapping_by_addr(&chan->alias_pairs, addr); + mutex_lock(&chan->alias_pairs_lock); + + c2a = i2c_atr_find_mapping_by_addr(chan, addr); if (!c2a) { /* This should never happen */ dev_warn(atr->dev, "Unable to find address mapping\n"); + mutex_unlock(&chan->alias_pairs_lock); return; } + mutex_unlock(&chan->alias_pairs_lock); + i2c_atr_release_alias(chan->alias_pool, c2a->alias); dev_dbg(atr->dev, @@ -538,7 +667,8 @@ static int i2c_atr_parse_alias_pool(struct i2c_atr *atr) } struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, - const struct i2c_atr_ops *ops, int max_adapters) + const struct i2c_atr_ops *ops, int max_adapters, + u16 flags) { struct i2c_atr *atr; int ret; @@ -559,6 +689,7 @@ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, atr->dev = dev; atr->ops = ops; atr->max_adapters = max_adapters; + atr->flags = flags; if (parent->algo->master_xfer) atr->algo.master_xfer = i2c_atr_master_xfer; @@ -631,6 +762,7 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, struct i2c_atr_adap_desc *desc) chan->atr = atr; chan->chan_id = chan_id; INIT_LIST_HEAD(&chan->alias_pairs); + mutex_init(&chan->alias_pairs_lock); mutex_init(&chan->orig_addrs_lock); snprintf(chan->adap.name, sizeof(chan->adap.name), "i2c-%d-atr-%d", @@ -707,6 +839,7 @@ int i2c_atr_add_adapter(struct i2c_atr *atr, struct i2c_atr_adap_desc *desc) err_fwnode_put: fwnode_handle_put(dev_fwnode(&chan->adap.dev)); mutex_destroy(&chan->orig_addrs_lock); + mutex_destroy(&chan->alias_pairs_lock); kfree(chan); return ret; } @@ -743,6 +876,7 @@ void i2c_atr_del_adapter(struct i2c_atr *atr, u32 chan_id) fwnode_handle_put(fwnode); mutex_destroy(&chan->orig_addrs_lock); + mutex_destroy(&chan->alias_pairs_lock); kfree(chan->orig_addrs); kfree(chan); } diff --git a/drivers/media/i2c/ds90ub960.c b/drivers/media/i2c/ds90ub960.c index 5a836731af6c701ef4070eb2dbab36cbdd86e0a2..06e7450d69877485360852ea9d811723b2ec8cb3 100644 --- a/drivers/media/i2c/ds90ub960.c +++ b/drivers/media/i2c/ds90ub960.c @@ -1099,7 +1099,7 @@ static int ub960_init_atr(struct ub960_data *priv) struct i2c_adapter *parent_adap = priv->client->adapter; priv->atr = i2c_atr_new(parent_adap, dev, &ub960_atr_ops, - priv->hw_data->num_rxports); + priv->hw_data->num_rxports, 0); if (IS_ERR(priv->atr)) return PTR_ERR(priv->atr); diff --git a/include/linux/i2c-atr.h b/include/linux/i2c-atr.h index 1c3a5bcd939fc56f4a6ca1b6a5cc0ac2c17083b7..9287f064b683cc3cf83016b720c4e6ccd38df426 100644 --- a/include/linux/i2c-atr.h +++ b/include/linux/i2c-atr.h @@ -65,6 +65,7 @@ struct i2c_atr_adap_desc { * @dev: The device acting as an ATR * @ops: Driver-specific callbacks * @max_adapters: Maximum number of child adapters + * @flags: Options to pass to the ATR framework. Allowed flags are I2C_ATR_FLAG_* * * The new ATR helper is connected to the parent adapter but has no child * adapters. Call i2c_atr_add_adapter() to add some. @@ -74,7 +75,17 @@ struct i2c_atr_adap_desc { * Return: pointer to the new ATR helper object, or ERR_PTR */ struct i2c_atr *i2c_atr_new(struct i2c_adapter *parent, struct device *dev, - const struct i2c_atr_ops *ops, int max_adapters); + const struct i2c_atr_ops *ops, int max_adapters, + u16 flags); + +/* + * I2C ATR flags + * + * I2C_ATR_FLAG_DYNAMIC_C2A: Dynamically update translation table when transfers + * targeting unmapped addresses are requested. + * + */ +#define I2C_ATR_FLAG_DYNAMIC_C2A BIT(0) /** * i2c_atr_delete - Delete an I2C ATR helper. From patchwork Fri Nov 8 15:37:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Romain Gantois X-Patchwork-Id: 842210 Received: from relay7-d.mail.gandi.net (relay7-d.mail.gandi.net [217.70.183.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AEC4D21FDB8; Fri, 8 Nov 2024 15:37:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.200 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731080242; cv=none; b=a8zvgdFcE3c98Y0dQY4nRwxKCzlEIkuYFXjkGuVR/3cwVRDTirf2gRQ/NDoDsyo1tuQLuHl3p25pKZeo+RzG+4tqasWb8OD5VZCMG3the35H61YOrHl0tKJk8v3qm/IHVyGEWyfsIeRAAPtp5nRtzhU0UiyPEI0qC8g+Tm6NNlw= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1731080242; c=relaxed/simple; bh=bqjbWQ1YgYFo5XPwkfcZQFKSUv7FMPnxtsWEX14HuYs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Ial3zidhKppzYDXJ0ks3LX+BvVNqx5jyAryrbm9rW4qAC/+20iu5C5vC4HSKhCP6fZmEeGPcLLSE8+f9D/lGdo2uPjUSIfK2mUoTgwwKhN6RSScLUC1SibAWbYQIjOowkDI+HCaFOW4SshMg/iXidht4Sv55Y66vvxgufqvQ2Zs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=hyfKMd6T; arc=none smtp.client-ip=217.70.183.200 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="hyfKMd6T" Received: by mail.gandi.net (Postfix) with ESMTPSA id 502822000E; Fri, 8 Nov 2024 15:37:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1731080237; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=pDGach98zHjQAfoDF7HC5mrbNv25j0XWgV1miw+ObeU=; b=hyfKMd6TGViNzXwhaKa3ub1scjR/2rLwlZhN5Ga4FiHqpXhjRIuCF272D64kR5iod7npji UVoPlqJFTMusT0n33A2AeQXC0K95dTGk2vsTidUAAR6GdgzcF4GZQNqr3E3PK5ms4dtOAs eDkPoFYajJpwosBstaQU8tR8YgG3MvPDU2n/Q51LVA9Jpfu7SJYv5jQ9/TLeEVm4miiC+8 qvvL6CvTwXhT6PpkAhQoojRNoRWmWYlB9kDK1a3c6LSi5JxsFiTBBBokAGLHlGoqblHjIh 8+RPal9wtMXNdBBdGWuXnj0dccn1zQwHVMbMzr1fhtIxQCwC/iFFyLZwELQw9w== From: Romain Gantois Date: Fri, 08 Nov 2024 16:37:01 +0100 Subject: [PATCH 9/9] misc: add FPC202 dual port controller driver Precedence: bulk X-Mailing-List: linux-i2c@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20241108-fpc202-v1-9-fe42c698bc92@bootlin.com> References: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> In-Reply-To: <20241108-fpc202-v1-0-fe42c698bc92@bootlin.com> To: Wolfram Sang , Tomi Valkeinen , Luca Ceresoli , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Derek Kiernan , Dragan Cvetic , Arnd Bergmann , Greg Kroah-Hartman , Mauro Carvalho Chehab Cc: Thomas Petazzoni , Kory Maincent , linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-media@vger.kernel.org, Romain Gantois X-Mailer: b4 0.14.2 X-GND-Sasl: romain.gantois@bootlin.com The TI FPC202 dual port controller serves as a low- speed signal aggregator for common port types such as SFP, QSFP, Mini-SAS HD, and others. It aggregates GPIO and I2C signals across two downstream ports, acting as both a GPIO controller and an I2C address translator for up to two logical devices per port. Signed-off-by: Romain Gantois --- MAINTAINERS | 7 + drivers/misc/Kconfig | 11 ++ drivers/misc/Makefile | 1 + drivers/misc/ti_fpc202.c | 421 +++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 440 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index c27f3190737f8b85779bde5489639c8b899f4fd8..4e686d6652f0395f4f2baf1e598aa6023a255a25 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -23223,6 +23223,13 @@ F: drivers/misc/tifm* F: drivers/mmc/host/tifm_sd.c F: include/linux/tifm.h +TI FPC202 DUAL PORT CONTROLLER +M: Romain Gantois +L: linux-kernel@vger.kernel.org +S: Maintained +F: Documentation/devicetree/bindings/misc/ti,fpc202.yaml +F: drivers/misc/ti_fpc202.c + TI FPD-LINK DRIVERS M: Tomi Valkeinen L: linux-media@vger.kernel.org diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 3fe7e2a9bd294da562cf553d958772dcb49bbc89..2549989422c5b1a67a886290efcd692c0835c7e1 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -114,6 +114,17 @@ config RPMB If unsure, select N. +config TI_FPC202 + tristate "TI FPC202 Dual Port Controller" + select GPIOLIB + depends on I2C_ATR + help + If you say yes here you get support for the Texas Instruments FPC202 + Dual Port Controller. + + This driver can also be built as a module. If so, the module will be + called fpc202. + config TIFM_CORE tristate "TI Flash Media interface support" depends on PCI diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index a9f94525e1819d5d7eed4937ce1d50b2875ee71b..d0b7a1b96619b3125d1455d40268040e0764b341 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -12,6 +12,7 @@ obj-$(CONFIG_ATMEL_SSC) += atmel-ssc.o obj-$(CONFIG_DUMMY_IRQ) += dummy-irq.o obj-$(CONFIG_ICS932S401) += ics932s401.o obj-$(CONFIG_LKDTM) += lkdtm/ +obj-$(CONFIG_TI_FPC202) += ti_fpc202.o obj-$(CONFIG_TIFM_CORE) += tifm_core.o obj-$(CONFIG_TIFM_7XX1) += tifm_7xx1.o obj-$(CONFIG_PHANTOM) += phantom.o diff --git a/drivers/misc/ti_fpc202.c b/drivers/misc/ti_fpc202.c new file mode 100644 index 0000000000000000000000000000000000000000..c2a720e10fa1391da43f469efb5f7ccd49320d44 --- /dev/null +++ b/drivers/misc/ti_fpc202.c @@ -0,0 +1,421 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ti_fpc202.c - FPC202 Dual Port Controller driver + * + * Copyright (C) 2024 Bootlin + * + */ + +#include +#include +#include +#include +#include +#include + +#define FPC202_ALIASES_PER_PORT 2 + +/* + * GPIO: port mapping + * + * 0: P0_S0_IN_A + * 1: P0_S1_IN_A + * 2: P1_S0_IN_A + * 3: P1_S1_IN_A + * 4: P0_S0_IN_B + * ... + * 8: P0_S0_IN_C + * ... + * 12: P0_S0_OUT_A + * ... + * 16: P0_S0_OUT_B + * ... + * 19: P1_S1_OUT_B + * + */ + +#define FPC202_GPIO_COUNT 20 +#define FPC202_GPIO_P0_S0_IN_B 4 +#define FPC202_GPIO_P0_S0_OUT_A 12 + +#define FPC202_REG_IN_A_INT 0x6 +#define FPC202_REG_IN_C_IN_B 0x7 +#define FPC202_REG_OUT_A_OUT_B 0x8 + +#define FPC202_REG_OUT_A_OUT_B_VAL 0xa + +#define FPC202_REG_MOD_DEV(port, dev) (0xb4 + ((port) * 4) + (dev)) +#define FPC202_REG_AUX_DEV(port, dev) (0xb6 + ((port) * 4) + (dev)) + +/* + * The FPC202 doesn't support turning off address translation on a single port. + * So just set an invalid I2C address as the translation target when no client + * address is attached. + */ +#define FPC202_REG_DEV_INVALID 0 + +/* Even aliases are assigned to device 0 and odd aliases to device 1 */ +#define fpc202_dev_num_from_alias(alias) ((alias) % 2) + +struct fpc202_priv { + struct i2c_client *client; + struct i2c_atr *atr; + struct gpio_desc *en_gpio; + struct gpio_chip gpio; + + /* Lock REG_MOD/AUX_DEV and addr_caches during attach/detach */ + struct mutex reg_dev_lock; + + /* Cached device addresses for both ports and their devices */ + u8 addr_caches[2][2]; +}; + +static void fpc202_fill_alias_table(struct i2c_client *client, u16 *aliases, int port_id) +{ + u16 first_alias; + int i; + + /* + * There is a predefined list of aliases for each FPC202 I2C + * self-address. This allows daisy-chained FPC202 units to + * automatically take on different sets of aliases. + * Each port of an FPC202 unit is assigned two aliases from this list. + */ + first_alias = 0x10 + 4 * port_id + 8 * ((u16)client->addr - 2); + + for (i = 0; i < FPC202_ALIASES_PER_PORT; i++) + aliases[i] = first_alias + i; +} + +static int fpc202_gpio_get_dir(int offset) +{ + return offset < FPC202_GPIO_P0_S0_OUT_A ? GPIO_LINE_DIRECTION_IN : GPIO_LINE_DIRECTION_OUT; +} + +static int fpc202_read(struct fpc202_priv *priv, u8 reg) +{ + int val; + + val = i2c_smbus_read_byte_data(priv->client, reg); + return val; +} + +static int fpc202_write(struct fpc202_priv *priv, u8 reg, u8 value) +{ + return i2c_smbus_write_byte_data(priv->client, reg, value); +} + +static void fpc202_set_enable(struct fpc202_priv *priv, int enable) +{ + if (!priv->en_gpio) + return; + + gpiod_set_value(priv->en_gpio, enable); +} + +static void fpc202_gpio_set(struct gpio_chip *chip, unsigned int offset, + int value) +{ + struct fpc202_priv *priv = gpiochip_get_data(chip); + int ret; + u8 val; + + if (fpc202_gpio_get_dir(offset) == GPIO_LINE_DIRECTION_IN) + return; + + ret = fpc202_read(priv, FPC202_REG_OUT_A_OUT_B_VAL); + if (ret < 0) { + dev_err(&priv->client->dev, "Failed to set GPIO %d value! err %d\n", offset, ret); + return; + } + + val = (u8)ret; + + if (value) + val |= BIT(offset - FPC202_GPIO_P0_S0_OUT_A); + else + val &= ~BIT(offset - FPC202_GPIO_P0_S0_OUT_A); + + fpc202_write(priv, FPC202_REG_OUT_A_OUT_B_VAL, val); +} + +static int fpc202_gpio_get(struct gpio_chip *chip, unsigned int offset) +{ + struct fpc202_priv *priv = gpiochip_get_data(chip); + u8 reg, bit; + int ret; + + if (offset < FPC202_GPIO_P0_S0_IN_B) { + reg = FPC202_REG_IN_A_INT; + bit = BIT(4 + offset); + } else if (offset < FPC202_GPIO_P0_S0_OUT_A) { + reg = FPC202_REG_IN_C_IN_B; + bit = BIT(offset - FPC202_GPIO_P0_S0_IN_B); + } else { + reg = FPC202_REG_OUT_A_OUT_B_VAL; + bit = BIT(offset - FPC202_GPIO_P0_S0_OUT_A); + } + + ret = fpc202_read(priv, reg); + if (ret < 0) + return ret; + + return !!(((u8)ret) & bit); +} + +static int fpc202_gpio_direction_input(struct gpio_chip *chip, unsigned int offset) +{ + if (fpc202_gpio_get_dir(offset) == GPIO_LINE_DIRECTION_OUT) + return -EINVAL; + + return 0; +} + +static int fpc202_gpio_direction_output(struct gpio_chip *chip, unsigned int offset, + int value) +{ + struct fpc202_priv *priv = gpiochip_get_data(chip); + int ret; + u8 val; + + if (fpc202_gpio_get_dir(offset) == GPIO_LINE_DIRECTION_IN) + return -EINVAL; + + fpc202_gpio_set(chip, offset, value); + + ret = fpc202_read(priv, FPC202_REG_OUT_A_OUT_B); + if (ret < 0) + return ret; + + val = (u8)ret | BIT(offset - FPC202_GPIO_P0_S0_OUT_A); + + return fpc202_write(priv, FPC202_REG_OUT_A_OUT_B, val); +} + +/* + * Set the translation table entry associated with a port and device number. + * + * Each downstream port of the FPC202 has two fixed aliases corresponding to + * device numbers 0 and 1. If one of these aliases is found in an incoming I2C + * transfer, it will be translated to the address given by the corresponding + * translation table entry. + */ +static int fpc202_write_dev_addr(struct fpc202_priv *priv, u32 port_id, int dev_num, u16 addr) +{ + int ret, reg_mod, reg_aux; + u8 val; + + mutex_lock(&priv->reg_dev_lock); + + reg_mod = FPC202_REG_MOD_DEV(port_id, dev_num); + reg_aux = FPC202_REG_AUX_DEV(port_id, dev_num); + val = addr & 0x7f; + + ret = fpc202_write(priv, reg_mod, val); + if (ret) + goto out_unlock; + + /* + * The FPC202 datasheet is unclear about the role of the AUX registers. + * Empirically, writing to them as well seems to be necessary for + * address translation to function properly. + */ + ret = fpc202_write(priv, reg_aux, val); + + priv->addr_caches[port_id][dev_num] = val; + +out_unlock: + mutex_unlock(&priv->reg_dev_lock); + return ret; +} + +static int fpc202_attach_addr(struct i2c_atr *atr, u32 chan_id, + u16 addr, u16 alias) +{ + struct fpc202_priv *priv = i2c_atr_get_driver_data(atr); + + dev_dbg(&priv->client->dev, "attaching address 0x%02x to alias 0x%02x\n", addr, alias); + + return fpc202_write_dev_addr(priv, chan_id, fpc202_dev_num_from_alias(alias), addr); +} + +static void fpc202_detach_addr(struct i2c_atr *atr, u32 chan_id, + u16 addr) +{ + struct fpc202_priv *priv = i2c_atr_get_driver_data(atr); + int dev_num, reg_mod, val; + + for (dev_num = 0; dev_num < 2; dev_num++) { + reg_mod = FPC202_REG_MOD_DEV(chan_id, dev_num); + + mutex_lock(&priv->reg_dev_lock); + + val = priv->addr_caches[chan_id][dev_num]; + + mutex_unlock(&priv->reg_dev_lock); + + if (val < 0) { + dev_err(&priv->client->dev, "failed to read register 0x%x while detaching address 0x%02x\n", + reg_mod, addr); + return; + } + + if (val == (addr & 0x7f)) { + fpc202_write_dev_addr(priv, chan_id, dev_num, FPC202_REG_DEV_INVALID); + return; + } + } +} + +struct i2c_atr_ops fpc202_atr_ops = { + .attach_addr = fpc202_attach_addr, + .detach_addr = fpc202_detach_addr, +}; + +static int fpc202_probe_port(struct fpc202_priv *priv, int port_id) +{ + struct device *dev = &priv->client->dev; + u16 aliases[FPC202_ALIASES_PER_PORT] = { }; + struct i2c_atr_adap_desc desc = { }; + struct device_node *i2c_handle; + char port_name[6]; + int ret = 0; + + if (port_id > 2) + return -EINVAL; + + snprintf(port_name, 6, "port%d", port_id); + + i2c_handle = of_get_child_by_name(dev->of_node, port_name); + if (!i2c_handle) + return -EINVAL; + + desc.chan_id = port_id; + desc.parent = dev; + desc.bus_handle = of_node_to_fwnode(i2c_handle); + desc.num_aliases = FPC202_ALIASES_PER_PORT; + + fpc202_fill_alias_table(priv->client, aliases, port_id); + desc.aliases = aliases; + + ret = i2c_atr_add_adapter(priv->atr, &desc); + if (ret) + return ret; + + of_node_put(i2c_handle); + + ret = fpc202_write_dev_addr(priv, port_id, 0, FPC202_REG_DEV_INVALID); + if (ret) + return ret; + + return fpc202_write_dev_addr(priv, port_id, 1, FPC202_REG_DEV_INVALID); +} + +static int fpc202_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct fpc202_priv *priv; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + mutex_init(&priv->reg_dev_lock); + + priv->client = client; + i2c_set_clientdata(client, priv); + + priv->en_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_HIGH); + if (IS_ERR(priv->en_gpio)) { + ret = PTR_ERR(priv->en_gpio); + dev_err(dev, "failed to fetch enable GPIO! err %d\n", ret); + goto destroy_mutex; + } + + priv->gpio.label = "gpio-fpc202"; + priv->gpio.base = -1; + priv->gpio.direction_input = fpc202_gpio_direction_input; + priv->gpio.direction_output = fpc202_gpio_direction_output; + priv->gpio.set = fpc202_gpio_set; + priv->gpio.get = fpc202_gpio_get; + priv->gpio.ngpio = FPC202_GPIO_COUNT; + priv->gpio.parent = dev; + priv->gpio.owner = THIS_MODULE; + + ret = gpiochip_add_data(&priv->gpio, priv); + if (ret) { + priv->gpio.parent = NULL; + dev_err(dev, "failed to add gpiochip err %d", ret); + goto disable_gpio; + } + + priv->atr = i2c_atr_new(client->adapter, dev, &fpc202_atr_ops, 2, I2C_ATR_FLAG_DYNAMIC_C2A); + if (IS_ERR(priv->atr)) { + ret = PTR_ERR(priv->atr); + dev_err(dev, "failed to create i2c atr err %d", ret); + goto disable_gpio; + } + + i2c_atr_set_driver_data(priv->atr, priv); + + ret = fpc202_probe_port(priv, 0); + if (ret) { + dev_err(dev, "Failed to probe port 0, err %d\n", ret); + goto delete_atr; + } + + ret = fpc202_probe_port(priv, 1); + if (ret) { + dev_err(dev, "Failed to probe port 1, err %d\n", ret); + goto delete_atr; + } + + dev_info(&client->dev, "%s FPC202 Dual Port controller found\n", client->name); + + goto out; + +delete_atr: + i2c_atr_delete(priv->atr); +disable_gpio: + fpc202_set_enable(priv, 0); + gpiochip_remove(&priv->gpio); +destroy_mutex: + mutex_destroy(&priv->reg_dev_lock); +out: + return ret; +} + +static void fpc202_remove(struct i2c_client *client) +{ + struct fpc202_priv *priv = i2c_get_clientdata(client); + + mutex_destroy(&priv->reg_dev_lock); + + i2c_atr_delete(priv->atr); + + fpc202_set_enable(priv, 0); + gpiochip_remove(&priv->gpio); +} + +static const struct of_device_id fpc202_of_match[] = { + { .compatible = "ti,fpc202" }, + {} +}; +MODULE_DEVICE_TABLE(of, fpc202_of_match); + +static struct i2c_driver fpc202_driver = { + .driver = { + .name = "fpc202", + .of_match_table = fpc202_of_match, + }, + .probe = fpc202_probe, + .remove = fpc202_remove, +}; + +module_i2c_driver(fpc202_driver); + +MODULE_AUTHOR("Romain Gantois "); +MODULE_DESCRIPTION("TI FPC202 Dual Port Controller driver"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(I2C_ATR);