From patchwork Tue Aug 6 13:14:07 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Valentina Fernandez X-Patchwork-Id: 817350 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.154.123]) (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 01CC31BF311; Tue, 6 Aug 2024 13:01:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=68.232.154.123 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722949279; cv=none; b=uGnQcbBcB9l/8CqugnKXW1MFyFxUq3pvicDR2IvKA5p5QCi2doX2rZz+A7R2r7poFR0hbZkqr7Y9+7mZuWAUfzlxP7cv+t7sNGm1h5CxefXVnFA3+mIq4Tmbk9/qka3474XnamnAYrWtPju+/rEv+FKjZjYBRTAyjO4+Nejd/tk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722949279; c=relaxed/simple; bh=rkmgOQl8py7qDrXITLdHSVEmk/LLPYkUA7Pt/ny9N3g=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=lTvEzYmvniyfsbmL23l1anxdVcEo6t8ucbHuthGj22Sr9e0Be2nYNGwyRvJ6iTV1ANhDdDK1VhGHpZD/rQtnpr12n0ma6Hwzf2wPOmECB59gWMwb34uYfFrt87z5Njb2hAay7NVrH0jVLztdDZN5IoDsXewwcrE4VBymOsbSWK8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=microchip.com; spf=pass smtp.mailfrom=microchip.com; dkim=pass (2048-bit key) header.d=microchip.com header.i=@microchip.com header.b=hiepdJHM; arc=none smtp.client-ip=68.232.154.123 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=microchip.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=microchip.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=microchip.com header.i=@microchip.com header.b="hiepdJHM" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1722949275; x=1754485275; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=rkmgOQl8py7qDrXITLdHSVEmk/LLPYkUA7Pt/ny9N3g=; b=hiepdJHMH2ZaXhRA8CK1J6PbKNLQQpsM8gXfN8FwPLIYXIRxINo201b/ 603NJGxAFc2dxQ+KGcCEdBGw/lH457lFNgTKM9sB5OlGNeW9Y+5pp0n5j HujqA6/zJFGw7HxkALfVtHgy8hK7KZsaAOI5y91+NOB6lPcOwy7Eg2Mar IBqwuIXm5NBPp2c850D/MABwMP9fUZfZ4VPxDeekIrkB4xLcSRss/vRW2 CrRdw30grN12UuMH0NPO+Lv9+2ILM9wbY1KYY+BlsBCttLOWMTYAb4Lz8 A4IUSn+neoqOU8oTFKWqo7B7Nid3Ap5IWmJ7aAQYukq48oIMeM6Le8P8C Q==; X-CSE-ConnectionGUID: 35PzH48ZQt27K00Yyxlz1w== X-CSE-MsgGUID: k16G+AKURLKjaYeL/9QOog== X-IronPort-AV: E=Sophos;i="6.09,267,1716274800"; d="scan'208";a="197573430" X-Amp-Result: SKIPPED(no attachment in message) Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa6.microchip.iphmx.com with ESMTP/TLS/ECDHE-RSA-AES128-GCM-SHA256; 06 Aug 2024 06:01:14 -0700 Received: from chn-vm-ex01.mchp-main.com (10.10.85.143) by chn-vm-ex03.mchp-main.com (10.10.85.151) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.35; Tue, 6 Aug 2024 06:01:01 -0700 Received: from valentina.microchip.com (10.10.85.11) by chn-vm-ex01.mchp-main.com (10.10.85.143) with Microsoft SMTP Server id 15.1.2507.35 via Frontend Transport; Tue, 6 Aug 2024 06:01:00 -0700 From: Valentina Fernandez To: CC: , , , , , , Subject: [PATCH v1] usb: musb: poll ID pin status in dual-role mode in mpfs glue layer Date: Tue, 6 Aug 2024 14:14:07 +0100 Message-ID: <20240806131407.1542306-1-valentina.fernandezalanis@microchip.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Similar to other platforms using the MUSB driver, PolarFire SoC lacks an ID pin interrupt event, preventing several OTG-critical status change events from being exposed. We need to rely on polling to detect USB attach events for the dual-role port. The otg state machine implementation is based on Texas Instruments DA8xx/OMAP-L1x glue layer. This has been tested on BeagleV-Fire with couple of devices in host mode and with the Ethernet gadget driver in peripheral mode, in a wide variety of plug orders. Signed-off-by: Valentina Fernandez --- drivers/usb/musb/mpfs.c | 160 ++++++++++++++++++++++++++++++++++------ 1 file changed, 136 insertions(+), 24 deletions(-) diff --git a/drivers/usb/musb/mpfs.c b/drivers/usb/musb/mpfs.c index 29c7e5cdb230..00e13214aa76 100644 --- a/drivers/usb/musb/mpfs.c +++ b/drivers/usb/musb/mpfs.c @@ -49,30 +49,6 @@ static const struct musb_hdrc_config mpfs_musb_hdrc_config = { .ram_bits = MPFS_MUSB_RAM_BITS, }; -static irqreturn_t mpfs_musb_interrupt(int irq, void *__hci) -{ - unsigned long flags; - irqreturn_t ret = IRQ_NONE; - struct musb *musb = __hci; - - spin_lock_irqsave(&musb->lock, flags); - - musb->int_usb = musb_readb(musb->mregs, MUSB_INTRUSB); - musb->int_tx = musb_readw(musb->mregs, MUSB_INTRTX); - musb->int_rx = musb_readw(musb->mregs, MUSB_INTRRX); - - if (musb->int_usb || musb->int_tx || musb->int_rx) { - musb_writeb(musb->mregs, MUSB_INTRUSB, musb->int_usb); - musb_writew(musb->mregs, MUSB_INTRTX, musb->int_tx); - musb_writew(musb->mregs, MUSB_INTRRX, musb->int_rx); - ret = musb_interrupt(musb); - } - - spin_unlock_irqrestore(&musb->lock, flags); - - return ret; -} - static void mpfs_musb_set_vbus(struct musb *musb, int is_on) { u8 devctl; @@ -111,6 +87,129 @@ static void mpfs_musb_set_vbus(struct musb *musb, int is_on) musb_readb(musb->mregs, MUSB_DEVCTL)); } +#define POLL_SECONDS 2 + +static void otg_timer(struct timer_list *t) +{ + struct musb *musb = from_timer(musb, t, dev_timer); + void __iomem *mregs = musb->mregs; + u8 devctl; + unsigned long flags; + + /* + * We poll because PolarFire SoC won't expose several OTG-critical + * status change events (from the transceiver) otherwise. + */ + devctl = musb_readb(mregs, MUSB_DEVCTL); + dev_dbg(musb->controller, "Poll devctl %02x (%s)\n", devctl, + usb_otg_state_string(musb->xceiv->otg->state)); + + spin_lock_irqsave(&musb->lock, flags); + switch (musb->xceiv->otg->state) { + case OTG_STATE_A_WAIT_BCON: + devctl &= ~MUSB_DEVCTL_SESSION; + musb_writeb(musb->mregs, MUSB_DEVCTL, devctl); + + devctl = musb_readb(musb->mregs, MUSB_DEVCTL); + if (devctl & MUSB_DEVCTL_BDEVICE) { + musb->xceiv->otg->state = OTG_STATE_B_IDLE; + MUSB_DEV_MODE(musb); + mod_timer(&musb->dev_timer, jiffies + POLL_SECONDS * HZ); + } else { + musb->xceiv->otg->state = OTG_STATE_A_IDLE; + MUSB_HST_MODE(musb); + } + break; + case OTG_STATE_A_WAIT_VFALL: + if (devctl & MUSB_DEVCTL_VBUS) { + mod_timer(&musb->dev_timer, jiffies + POLL_SECONDS * HZ); + break; + } + musb->xceiv->otg->state = OTG_STATE_A_WAIT_VRISE; + break; + case OTG_STATE_B_IDLE: + /* + * There's no ID-changed IRQ, so we have no good way to tell + * when to switch to the A-Default state machine (by setting + * the DEVCTL.Session bit). + * + * Workaround: whenever we're in B_IDLE, try setting the + * session flag every few seconds. If it works, ID was + * grounded and we're now in the A-Default state machine. + * + * NOTE: setting the session flag is _supposed_ to trigger + * SRP but clearly it doesn't. + */ + musb_writeb(mregs, MUSB_DEVCTL, devctl | MUSB_DEVCTL_SESSION); + devctl = musb_readb(mregs, MUSB_DEVCTL); + if (devctl & MUSB_DEVCTL_BDEVICE) + mod_timer(&musb->dev_timer, jiffies + POLL_SECONDS * HZ); + else + musb->xceiv->otg->state = OTG_STATE_A_IDLE; + break; + default: + break; + } + spin_unlock_irqrestore(&musb->lock, flags); +} + +static void __maybe_unused mpfs_musb_try_idle(struct musb *musb, unsigned long timeout) +{ + static unsigned long last_timer; + + if (timeout == 0) + timeout = jiffies + msecs_to_jiffies(3); + + /* Never idle if active, or when VBUS timeout is not set as host */ + if (musb->is_active || (musb->a_wait_bcon == 0 && + musb->xceiv->otg->state == OTG_STATE_A_WAIT_BCON)) { + dev_dbg(musb->controller, "%s active, deleting timer\n", + usb_otg_state_string(musb->xceiv->otg->state)); + del_timer(&musb->dev_timer); + last_timer = jiffies; + return; + } + + if (time_after(last_timer, timeout) && timer_pending(&musb->dev_timer)) { + dev_dbg(musb->controller, "Longer idle timer already pending, ignoring...\n"); + return; + } + last_timer = timeout; + + dev_dbg(musb->controller, "%s inactive, starting idle timer for %u ms\n", + usb_otg_state_string(musb->xceiv->otg->state), + jiffies_to_msecs(timeout - jiffies)); + mod_timer(&musb->dev_timer, timeout); +} + +static irqreturn_t mpfs_musb_interrupt(int irq, void *__hci) +{ + unsigned long flags; + irqreturn_t ret = IRQ_NONE; + struct musb *musb = __hci; + + spin_lock_irqsave(&musb->lock, flags); + + musb->int_usb = musb_readb(musb->mregs, MUSB_INTRUSB); + musb->int_tx = musb_readw(musb->mregs, MUSB_INTRTX); + musb->int_rx = musb_readw(musb->mregs, MUSB_INTRRX); + + if (musb->int_usb || musb->int_tx || musb->int_rx) { + musb_writeb(musb->mregs, MUSB_INTRUSB, musb->int_usb); + musb_writew(musb->mregs, MUSB_INTRTX, musb->int_tx); + musb_writew(musb->mregs, MUSB_INTRRX, musb->int_rx); + ret = musb_interrupt(musb); + } + + /* Poll for ID change */ + if (musb->xceiv->otg->state == OTG_STATE_B_IDLE) + mod_timer(&musb->dev_timer, jiffies + POLL_SECONDS * HZ); + + spin_unlock_irqrestore(&musb->lock, flags); + + return ret; +} + static int mpfs_musb_init(struct musb *musb) { struct device *dev = musb->controller; @@ -121,6 +220,8 @@ static int mpfs_musb_init(struct musb *musb) return PTR_ERR(musb->xceiv); } + timer_setup(&musb->dev_timer, otg_timer, 0); + musb->dyn_fifo = true; musb->isr = mpfs_musb_interrupt; @@ -129,13 +230,24 @@ static int mpfs_musb_init(struct musb *musb) return 0; } +static int mpfs_musb_exit(struct musb *musb) +{ + del_timer_sync(&musb->dev_timer); + + return 0; +} + static const struct musb_platform_ops mpfs_ops = { .quirks = MUSB_DMA_INVENTRA, .init = mpfs_musb_init, + .exit = mpfs_musb_exit, .fifo_mode = 2, #ifdef CONFIG_USB_INVENTRA_DMA .dma_init = musbhs_dma_controller_create, .dma_exit = musbhs_dma_controller_destroy, +#endif +#ifndef CONFIG_USB_MUSB_HOST + .try_idle = mpfs_musb_try_idle, #endif .set_vbus = mpfs_musb_set_vbus };