From patchwork Mon Mar 4 12:27:04 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Shevchenko X-Patchwork-Id: 778261 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.12]) (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 050CA3D968; Mon, 4 Mar 2024 12:30:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.12 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709555451; cv=none; b=P21CqzKOkmrMQq+/GsU4wbCIq94G/M3oX+B2hWZr3CzWVjVBPMR7vDLzCQKB8fx4ZufB9tRwggGw4rbZw3DWJ/Hc5iR4IAMNKtQ6RI+Fp+ZbClCpeme9I5ARJd/VtNuTW6BSj+an2A3LnKkGiN5SLkhrj4ledczPbsw4fdmnKPo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709555451; c=relaxed/simple; bh=MzeE3/tXNoP+XePWQLaHjZ7JMNhfc4kTQ5ZC6sxw0R8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VD/wWsECvZJIVJlu/fOXs21WGfzkrkPzVkYIu6cqvvWW1cEIVyG00cUAGNUNzX6DCG8aufWlrAcjDhu3K20t+N4uOtoyJc0Ss2xtyajaiQAgnMSMPVVbfAEqB/pzT8GbUj7x/llebFszxrzsbilnko/JM1+zBZiPQV0z92cnbYk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=n6sIToEd; arc=none smtp.client-ip=192.198.163.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="n6sIToEd" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1709555450; x=1741091450; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=MzeE3/tXNoP+XePWQLaHjZ7JMNhfc4kTQ5ZC6sxw0R8=; b=n6sIToEdEEtPs9Rh7TkeQYpI6KWVlUXBYBd17zxvKeZ0qz9IRZ1Xr9hq A0aXZbo03OEHWL5mrUh7Z7iFSiqKAWfKtMdsmW29+l7UtX/mKz/I/XfUF 48pI6qkBQhExmrBntB+JDnX+gUv6l8Yo7S0i+vES5h1kMhKVS9FnAPv6R AzRWb/QHcDVJkjX2RZ584+nUnPWyUryfGkwgPfcAKBjmu+lvE6vsUmeqc 88R0M3kvyz5CvyeHXiC6I9wSd25cI175FpHPOECrv0Q6bwSSAoi/pU1nB fPpwkT9+MCcjWHr8PT8cNTLQbJdDJs5MJJhE+qBvf7R50A2TYbbPhpx2O w==; X-IronPort-AV: E=McAfee;i="6600,9927,11002"; a="7815073" X-IronPort-AV: E=Sophos;i="6.06,203,1705392000"; d="scan'208";a="7815073" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmvoesa106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Mar 2024 04:30:44 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,11002"; a="937040424" X-IronPort-AV: E=Sophos;i="6.06,203,1705392000"; d="scan'208";a="937040424" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga001.fm.intel.com with ESMTP; 04 Mar 2024 04:30:38 -0800 Received: by black.fi.intel.com (Postfix, from userid 1003) id 58ECA3F1; Mon, 4 Mar 2024 14:30:37 +0200 (EET) From: Andy Shevchenko To: Greg Kroah-Hartman , Andy Shevchenko , Florian Fainelli , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org, linux-rpi-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linux-tegra@vger.kernel.org Cc: Jiri Slaby , Joel Stanley , Andrew Jeffery , Broadcom internal kernel review list , Ray Jui , Scott Branden , Al Cooper , =?utf-8?q?Ilpo_J=C3=A4rvinen?= , Paul Cercueil , Vladimir Zapolskiy , Thierry Reding , Jonathan Hunter , Kunihiko Hayashi , Masami Hiramatsu Subject: [PATCH v3 03/14] serial: port: Introduce a common helper to read properties Date: Mon, 4 Mar 2024 14:27:04 +0200 Message-ID: <20240304123035.758700-4-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.43.0.rc1.1.gbec44491f096 In-Reply-To: <20240304123035.758700-1-andriy.shevchenko@linux.intel.com> References: <20240304123035.758700-1-andriy.shevchenko@linux.intel.com> Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Several serial drivers want to read the same or similar set of the port properties. Make a common helper for them. Signed-off-by: Andy Shevchenko --- drivers/tty/serial/serial_port.c | 145 +++++++++++++++++++++++++++++++ include/linux/serial_core.h | 2 + 2 files changed, 147 insertions(+) diff --git a/drivers/tty/serial/serial_port.c b/drivers/tty/serial/serial_port.c index 72b6f4f326e2..22b9eeb23e68 100644 --- a/drivers/tty/serial/serial_port.c +++ b/drivers/tty/serial/serial_port.c @@ -8,7 +8,10 @@ #include #include +#include +#include #include +#include #include #include @@ -105,6 +108,148 @@ void uart_remove_one_port(struct uart_driver *drv, struct uart_port *port) } EXPORT_SYMBOL(uart_remove_one_port); +/** + * __uart_read_properties - read firmware properties of the given UART port + * @port: corresponding port + * @use_defaults: apply defaults (when %true) or validate the values (when %false) + * + * The following device properties are supported: + * - clock-frequency (optional) + * - fifo-size (optional) + * - no-loopback-test (optional) + * - reg-shift (defaults may apply) + * - reg-offset (value may be validated) + * - reg-io-width (defaults may apply or value may be validated) + * - interrupts (OF only) + * - serial [alias ID] (OF only) + * + * If the port->dev is of struct platform_device type the interrupt line + * will be retrieved via platform_get_irq() call against that device. + * Otherwise it will be assigned by fwnode_irq_get() call. In both cases + * the index 0 of the resource is used. + * + * The caller is responsible to initialize the following fields of the @port + * ->dev (must be valid) + * ->flags + * ->mapbase + * ->mapsize + * ->regshift (if @use_defaults is false) + * before calling this function. Alternatively the above mentioned fields + * may be zeroed, in such case the only ones, that have associated properties + * found, will be set to the respective values. + * + * If no error happened, the ->irq, ->mapbase, ->mapsize will be altered. + * The ->iotype is always altered. + * + * When @use_defaults is true and the respective property is not found + * the following values will be applied: + * ->regshift = 0 + * In this case IRQ must be provided, otherwise an error will be returned. + * + * When @use_defaults is false and the respective property is found + * the following values will be validated: + * - reg-io-width (->iotype) + * - reg-offset (->mapsize against ->mapbase) + * + * Returns: 0 on success or negative errno on failure + */ +static int __uart_read_properties(struct uart_port *port, bool use_defaults) +{ + struct device *dev = port->dev; + u32 value; + int ret; + + /* Read optional UART functional clock frequency */ + device_property_read_u32(dev, "clock-frequency", &port->uartclk); + + /* Read the registers alignment (default: 8-bit) */ + ret = device_property_read_u32(dev, "reg-shift", &value); + if (ret) + port->regshift = use_defaults ? 0 : port->regshift; + else + port->regshift = value; + + /* Read the registers I/O access type (default: MMIO 8-bit) */ + ret = device_property_read_u32(dev, "reg-io-width", &value); + if (ret) { + port->iotype = UPIO_MEM; + } else { + switch (value) { + case 1: + port->iotype = UPIO_MEM; + break; + case 2: + port->iotype = UPIO_MEM16; + break; + case 4: + port->iotype = device_is_big_endian(dev) ? UPIO_MEM32BE : UPIO_MEM32; + break; + default: + if (!use_defaults) { + dev_err(dev, "Unsupported reg-io-width (%u)\n", value); + return -EINVAL; + } + port->iotype = UPIO_UNKNOWN; + break; + } + } + + /* Read the address mapping base offset (default: no offset) */ + ret = device_property_read_u32(dev, "reg-offset", &value); + if (ret) + value = 0; + + /* Check for shifted address mapping overflow */ + if (!use_defaults && port->mapsize < value) { + dev_err(dev, "reg-offset %u exceeds region size %pa\n", value, &port->mapsize); + return -EINVAL; + } + + port->mapbase += value; + port->mapsize -= value; + + /* Read optional FIFO size */ + device_property_read_u32(dev, "fifo-size", &port->fifosize); + + if (device_property_read_bool(dev, "no-loopback-test")) + port->flags |= UPF_SKIP_TEST; + + /* Get index of serial line, if found in DT aliases */ + ret = of_alias_get_id(dev_of_node(dev), "serial"); + if (ret >= 0) + port->line = ret; + + if (dev_is_platform(dev)) + ret = platform_get_irq(to_platform_device(dev), 0); + else + ret = fwnode_irq_get(dev_fwnode(dev), 0); + if (ret == -EPROBE_DEFER) + return ret; + if (ret > 0) + port->irq = ret; + else if (use_defaults) + /* By default IRQ support is mandatory */ + return ret; + else + port->irq = 0; + + port->flags |= UPF_SHARE_IRQ; + + return 0; +} + +int uart_read_port_properties(struct uart_port *port) +{ + return __uart_read_properties(port, true); +} +EXPORT_SYMBOL_GPL(uart_read_port_properties); + +int uart_read_and_validate_port_properties(struct uart_port *port) +{ + return __uart_read_properties(port, false); +} +EXPORT_SYMBOL_GPL(uart_read_and_validate_port_properties); + static struct device_driver serial_port_driver = { .name = "port", .suppress_bind_attrs = true, diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h index c2cf9484014c..c1fd3d2f6238 100644 --- a/include/linux/serial_core.h +++ b/include/linux/serial_core.h @@ -962,6 +962,8 @@ int uart_register_driver(struct uart_driver *uart); void uart_unregister_driver(struct uart_driver *uart); int uart_add_one_port(struct uart_driver *reg, struct uart_port *port); void uart_remove_one_port(struct uart_driver *reg, struct uart_port *port); +int uart_read_port_properties(struct uart_port *port); +int uart_read_and_validate_port_properties(struct uart_port *port); bool uart_match_port(const struct uart_port *port1, const struct uart_port *port2);