From patchwork Tue Oct 6 16:08:12 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Christian Eggers X-Patchwork-Id: 1377531 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-i2c-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arri.de Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4C5Mqv4mLPz9sTD for ; Wed, 7 Oct 2020 03:10:03 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725947AbgJFQKD (ORCPT ); Tue, 6 Oct 2020 12:10:03 -0400 Received: from mailout11.rmx.de ([94.199.88.76]:49194 "EHLO mailout11.rmx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725946AbgJFQKC (ORCPT ); Tue, 6 Oct 2020 12:10:02 -0400 Received: from kdin01.retarus.com (kdin01.dmz1.retloc [172.19.17.48]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mailout11.rmx.de (Postfix) with ESMTPS id 4C5Mqn71bxz40dw; Tue, 6 Oct 2020 18:09:57 +0200 (CEST) Received: from mta.arri.de (unknown [217.111.95.66]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by kdin01.retarus.com (Postfix) with ESMTPS id 4C5Mpv1Grzz2xNp; Tue, 6 Oct 2020 18:09:11 +0200 (CEST) Received: from N95HX1G2.wgnetz.xx (192.168.54.45) by mta.arri.de (192.168.100.104) with Microsoft SMTP Server (TLS) id 14.3.408.0; Tue, 6 Oct 2020 18:08:58 +0200 From: Christian Eggers To: Oleksij Rempel , Shawn Guo , Sascha Hauer , Fabio Estevam , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , "David Laight" CC: Pengutronix Kernel Team , NXP Linux Team , , , , Christian Eggers , Subject: [PATCH v4 1/3] i2c: imx: Fix reset of I2SR_IAL flag Date: Tue, 6 Oct 2020 18:08:12 +0200 Message-ID: <20201006160814.22047-2-ceggers@arri.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201006160814.22047-1-ceggers@arri.de> References: <20201006160814.22047-1-ceggers@arri.de> MIME-Version: 1.0 X-Originating-IP: [192.168.54.45] X-RMX-ID: 20201006-180911-4C5Mpv1Grzz2xNp-0@kdin01 X-RMX-SOURCE: 217.111.95.66 Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org According to the "VFxxx Controller Reference Manual" (and the comment block starting at line 97), Vybrid requires writing a one for clearing an interrupt flag. Syncing the method for clearing I2SR_IIF in i2c_imx_isr(). Signed-off-by: Christian Eggers Cc: stable@vger.kernel.org Reviewed-by: Uwe Kleine-König --- drivers/i2c/busses/i2c-imx.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index 0ab5381aa012..cbdcab73a055 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -412,6 +412,19 @@ static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx) dma->chan_using = NULL; } +static void i2c_imx_clear_irq(struct imx_i2c_struct *i2c_imx, unsigned int bits) +{ + unsigned int temp; + + /* + * i2sr_clr_opcode is the value to clear all interrupts. Here we want to + * clear only , so we write ~i2sr_clr_opcode with just + * toggled. This is required because i.MX needs W1C and Vybrid uses W0C. + */ + temp = ~i2c_imx->hwdata->i2sr_clr_opcode ^ bits; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); +} + static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool atomic) { unsigned long orig_jiffies = jiffies; @@ -424,8 +437,7 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool a /* check for arbitration lost */ if (temp & I2SR_IAL) { - temp &= ~I2SR_IAL; - imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); + i2c_imx_clear_irq(i2c_imx, I2SR_IAL); return -EAGAIN; } @@ -623,9 +635,7 @@ static irqreturn_t i2c_imx_isr(int irq, void *dev_id) if (temp & I2SR_IIF) { /* save status register */ i2c_imx->i2csr = temp; - temp &= ~I2SR_IIF; - temp |= (i2c_imx->hwdata->i2sr_clr_opcode & I2SR_IIF); - imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); + i2c_imx_clear_irq(i2c_imx, I2SR_IIF); wake_up(&i2c_imx->queue); return IRQ_HANDLED; } From patchwork Tue Oct 6 16:08:13 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Eggers X-Patchwork-Id: 1377534 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-i2c-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arri.de Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4C5Ms56htmz9sTK for ; Wed, 7 Oct 2020 03:11:05 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726137AbgJFQLB (ORCPT ); Tue, 6 Oct 2020 12:11:01 -0400 Received: from mailout11.rmx.de ([94.199.88.76]:50652 "EHLO mailout11.rmx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725769AbgJFQLB (ORCPT ); Tue, 6 Oct 2020 12:11:01 -0400 Received: from kdin01.retarus.com (kdin01.dmz1.retloc [172.19.17.48]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mailout11.rmx.de (Postfix) with ESMTPS id 4C5Mrw5w11z40qX; Tue, 6 Oct 2020 18:10:56 +0200 (CEST) Received: from mta.arri.de (unknown [217.111.95.66]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by kdin01.retarus.com (Postfix) with ESMTPS id 4C5Mqn6vl6z2xZn; Tue, 6 Oct 2020 18:09:57 +0200 (CEST) Received: from N95HX1G2.wgnetz.xx (192.168.54.45) by mta.arri.de (192.168.100.104) with Microsoft SMTP Server (TLS) id 14.3.408.0; Tue, 6 Oct 2020 18:09:33 +0200 From: Christian Eggers To: Oleksij Rempel , Shawn Guo , Sascha Hauer , Fabio Estevam , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , "David Laight" CC: Pengutronix Kernel Team , NXP Linux Team , , , , Christian Eggers , Subject: [PATCH v4 2/3] i2c: imx: Check for I2SR_IAL after every byte Date: Tue, 6 Oct 2020 18:08:13 +0200 Message-ID: <20201006160814.22047-3-ceggers@arri.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201006160814.22047-1-ceggers@arri.de> References: <20201006160814.22047-1-ceggers@arri.de> MIME-Version: 1.0 X-Originating-IP: [192.168.54.45] X-RMX-ID: 20201006-181001-4C5Mqn6vl6z2xZn-0@kdin01 X-RMX-SOURCE: 217.111.95.66 Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org Arbitration Lost (IAL) can happen after every single byte transfer. If arbitration is lost, the I2C hardware will autonomously switch from master mode to slave. If a transfer is not aborted in this state, consecutive transfers will not be executed by the hardware and will timeout. Signed-off-by: Christian Eggers Cc: stable@vger.kernel.org --- drivers/i2c/busses/i2c-imx.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index cbdcab73a055..63575af41c09 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -490,6 +490,16 @@ static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx, bool atomic) dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__); return -ETIMEDOUT; } + + /* check for arbitration lost */ + if (i2c_imx->i2csr & I2SR_IAL) { + dev_dbg(&i2c_imx->adapter.dev, "<%s> Arbitration lost\n", __func__); + i2c_imx_clear_irq(i2c_imx, I2SR_IAL); + + i2c_imx->i2csr = 0; + return -EAGAIN; + } + dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__); i2c_imx->i2csr = 0; return 0; From patchwork Tue Oct 6 16:08:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Eggers X-Patchwork-Id: 1377536 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-i2c-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arri.de Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4C5Mt20zfvz9sSs for ; Wed, 7 Oct 2020 03:11:54 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725947AbgJFQLx (ORCPT ); Tue, 6 Oct 2020 12:11:53 -0400 Received: from mailout12.rmx.de ([94.199.88.78]:38157 "EHLO mailout12.rmx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725769AbgJFQLw (ORCPT ); Tue, 6 Oct 2020 12:11:52 -0400 Received: from kdin01.retarus.com (kdin01.dmz1.retloc [172.19.17.48]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mailout12.rmx.de (Postfix) with ESMTPS id 4C5Msv4MsxzRq0K; Tue, 6 Oct 2020 18:11:47 +0200 (CEST) Received: from mta.arri.de (unknown [217.111.95.66]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by kdin01.retarus.com (Postfix) with ESMTPS id 4C5Mrw5nVzz2xqM; Tue, 6 Oct 2020 18:10:56 +0200 (CEST) Received: from N95HX1G2.wgnetz.xx (192.168.54.45) by mta.arri.de (192.168.100.104) with Microsoft SMTP Server (TLS) id 14.3.408.0; Tue, 6 Oct 2020 18:10:03 +0200 From: Christian Eggers To: Oleksij Rempel , Shawn Guo , Sascha Hauer , Fabio Estevam , =?utf-8?q?Uwe_Kleine-K=C3=B6nig?= , "David Laight" CC: Pengutronix Kernel Team , NXP Linux Team , , , , Christian Eggers , Subject: [PATCH v4 3/3] i2c: imx: Don't generate STOP condition if arbitration has been lost Date: Tue, 6 Oct 2020 18:08:14 +0200 Message-ID: <20201006160814.22047-4-ceggers@arri.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201006160814.22047-1-ceggers@arri.de> References: <20201006160814.22047-1-ceggers@arri.de> MIME-Version: 1.0 X-Originating-IP: [192.168.54.45] X-RMX-ID: 20201006-181104-4C5Mrw5nVzz2xqM-0@kdin01 X-RMX-SOURCE: 217.111.95.66 Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org If arbitration is lost, the master automatically changes to slave mode. I2SR_IBB may or may not be reset by hardware. Raising a STOP condition by resetting I2CR_MSTA has no effect and will not clear I2SR_IBB. So calling i2c_imx_bus_busy() is not required and would busy-wait until timeout. Signed-off-by: Christian Eggers Cc: stable@vger.kernel.org # Requires trivial backporting, simple remove # the 3rd argument from the calls to # i2c_imx_bus_busy(). --- drivers/i2c/busses/i2c-imx.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index 63575af41c09..5d8a79319b2b 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -615,6 +615,8 @@ static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx, bool atomic) /* Stop I2C transaction */ dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + if (!(temp & I2CR_MSTA)) + i2c_imx->stopped = 1; temp &= ~(I2CR_MSTA | I2CR_MTX); if (i2c_imx->dma) temp &= ~I2CR_DMAEN; @@ -778,9 +780,12 @@ static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx, */ dev_dbg(dev, "<%s> clear MSTA\n", __func__); temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + if (!(temp & I2CR_MSTA)) + i2c_imx->stopped = 1; temp &= ~(I2CR_MSTA | I2CR_MTX); imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); - i2c_imx_bus_busy(i2c_imx, 0, false); + if (!i2c_imx->stopped) + i2c_imx_bus_busy(i2c_imx, 0, false); } else { /* * For i2c master receiver repeat restart operation like: @@ -905,9 +910,12 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, dev_dbg(&i2c_imx->adapter.dev, "<%s> clear MSTA\n", __func__); temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + if (!(temp & I2CR_MSTA)) + i2c_imx->stopped = 1; temp &= ~(I2CR_MSTA | I2CR_MTX); imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); - i2c_imx_bus_busy(i2c_imx, 0, atomic); + if (!i2c_imx->stopped) + i2c_imx_bus_busy(i2c_imx, 0, atomic); } else { /* * For i2c master receiver repeat restart operation like: