From 3a48d1c08fe0db79b8647b7042e6a077588b374a Mon Sep 17 00:00:00 2001 From: Kristen Carlson Accardi Date: Tue, 10 Apr 2012 14:15:41 +0100 Subject: i2c: prevent spurious interrupt on Designware controllers Don't call i2c_enable on resume because it causes a spurious interrupt. Signed-off-by: Kristen Carlson Accardi Signed-off-by: Kirill A. Shutemov Signed-off-by: Alan Cox Signed-off-by: Linus Torvalds --- drivers/i2c/busses/i2c-designware-pcidrv.c | 1 - 1 file changed, 1 deletion(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/busses/i2c-designware-pcidrv.c b/drivers/i2c/busses/i2c-designware-pcidrv.c index 37f42113af3..00e8f213f56 100644 --- a/drivers/i2c/busses/i2c-designware-pcidrv.c +++ b/drivers/i2c/busses/i2c-designware-pcidrv.c @@ -182,7 +182,6 @@ static int i2c_dw_pci_resume(struct device *dev) pci_restore_state(pdev); i2c_dw_init(i2c); - i2c_dw_enable(i2c); return 0; } -- cgit v1.2.3-70-g09d2 From 6c557cfee08751d22aed34840f389b846f0f4508 Mon Sep 17 00:00:00 2001 From: Roland Stigge Date: Wed, 4 Apr 2012 10:34:37 +0200 Subject: i2c: pnx: Disable clk in suspend In the driver's suspend function, clk_enable() was used instead of clk_disable(). This is corrected with this patch. Signed-off-by: Roland Stigge Reviewed-by: Arnd Bergmann CC: stable@vger.kernel.org [wsa: reworded commit header slightly] Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-pnx.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/busses/i2c-pnx.c b/drivers/i2c/busses/i2c-pnx.c index 04be9f82e14..eb8ad538c79 100644 --- a/drivers/i2c/busses/i2c-pnx.c +++ b/drivers/i2c/busses/i2c-pnx.c @@ -546,8 +546,7 @@ static int i2c_pnx_controller_suspend(struct platform_device *pdev, { struct i2c_pnx_algo_data *alg_data = platform_get_drvdata(pdev); - /* FIXME: shouldn't this be clk_disable? */ - clk_enable(alg_data->clk); + clk_disable(alg_data->clk); return 0; } -- cgit v1.2.3-70-g09d2 From f70893d08338b9cab8008d2e30404ce58930a513 Mon Sep 17 00:00:00 2001 From: Alok Chauhan Date: Mon, 2 Apr 2012 11:23:02 +0530 Subject: i2c: tegra: Add delay before resetting the controller after NACK NACK interrupt is generated before I2C controller generates the STOP condition on bus. Because of this reset of controller is happening before I2C controller could complete STOP condition. So wait for some time before resetting the controller so that STOP condition has delivered properly on bus. Added delay of 2 clock period before resetting the controller in case of NACK error. Signed-off-by: Alok Chauhan Acked-by: Stephen Warren [wsa: Reworded the commit msg and code comment a bit] Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-tegra.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'drivers/i2c') diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index e978635e60f..55e5ea62cce 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -516,6 +516,14 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev, if (likely(i2c_dev->msg_err == I2C_ERR_NONE)) return 0; + /* + * NACK interrupt is generated before the I2C controller generates the + * STOP condition on the bus. So wait for 2 clock periods before resetting + * the controller so that STOP condition has been delivered properly. + */ + if (i2c_dev->msg_err == I2C_ERR_NO_ACK) + udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev->bus_clk_rate)); + tegra_i2c_init(i2c_dev); if (i2c_dev->msg_err == I2C_ERR_NO_ACK) { if (msg->flags & I2C_M_IGNORE_NAK) -- cgit v1.2.3-70-g09d2 From 8a52f9f347da721b199b7f9dcc0168bbe7d0baae Mon Sep 17 00:00:00 2001 From: Tomoya MORINAGA Date: Mon, 26 Mar 2012 14:55:25 +0900 Subject: i2c-eg20t: change timeout value 50msec to 1000msec Currently, during i2c works alone, wait-event timeout is not occurred. However, as CPU load increases, timeout occurs frequently. So, I modified like this patch. Modifying like this patch, I've never seen the timeout event with high load test. Signed-off-by: Tomoya MORINAGA Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-eg20t.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c index f086131cb1c..4a46c8b1818 100644 --- a/drivers/i2c/busses/i2c-eg20t.c +++ b/drivers/i2c/busses/i2c-eg20t.c @@ -324,7 +324,7 @@ static s32 pch_i2c_wait_for_xfer_complete(struct i2c_algo_pch_data *adap) { long ret; ret = wait_event_timeout(pch_event, - (adap->pch_event_flag != 0), msecs_to_jiffies(50)); + (adap->pch_event_flag != 0), msecs_to_jiffies(1000)); if (ret == 0) { pch_err(adap, "timeout: %x\n", adap->pch_event_flag); -- cgit v1.2.3-70-g09d2 From 096407136769ec10690abe1baba092abcb763662 Mon Sep 17 00:00:00 2001 From: Tomoya MORINAGA Date: Mon, 26 Mar 2012 14:55:23 +0900 Subject: i2c-eg20t: Modify MODULE_AUTHOR's email address Signed-off-by: Tomoya MORINAGA Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-eg20t.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c index 4a46c8b1818..c811289b61e 100644 --- a/drivers/i2c/busses/i2c-eg20t.c +++ b/drivers/i2c/busses/i2c-eg20t.c @@ -1063,6 +1063,6 @@ module_exit(pch_pci_exit); MODULE_DESCRIPTION("Intel EG20T PCH/LAPIS Semico ML7213/ML7223/ML7831 IOH I2C"); MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Tomoya MORINAGA. "); +MODULE_AUTHOR("Tomoya MORINAGA. "); module_param(pch_i2c_speed, int, (S_IRUSR | S_IWUSR)); module_param(pch_clk, int, (S_IRUSR | S_IWUSR)); -- cgit v1.2.3-70-g09d2 From c95eeae9e39314273bcda057f27100603d333518 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Thu, 5 Apr 2012 16:15:24 +0200 Subject: i2c: mxs: handle spurious interrupt After an error interrupt setting cmd->err, I see another interrupt that the data engine is empty which clears cmd->err before being processed. So, clear cmd->err at the beginning of a transfer only to handle these consecutive interrupts. Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-mxs.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c index 3d471d56bf1..4c37347973e 100644 --- a/drivers/i2c/busses/i2c-mxs.c +++ b/drivers/i2c/busses/i2c-mxs.c @@ -227,6 +227,7 @@ static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, return -EINVAL; init_completion(&i2c->cmd_complete); + i2c->cmd_err = 0; flags = stop ? MXS_I2C_CTRL0_POST_SEND_STOP : 0; @@ -299,8 +300,6 @@ static irqreturn_t mxs_i2c_isr(int this_irq, void *dev_id) MXS_I2C_CTRL1_SLAVE_STOP_IRQ | MXS_I2C_CTRL1_SLAVE_IRQ)) /* MXS_I2C_CTRL1_OVERSIZE_XFER_TERM_IRQ is only for slaves */ i2c->cmd_err = -EIO; - else - i2c->cmd_err = 0; is_last_cmd = (readl(i2c->regs + MXS_I2C_QUEUESTAT) & MXS_I2C_QUEUESTAT_WRITE_QUEUE_CNT_MASK) == 0; -- cgit v1.2.3-70-g09d2 From 1e4f0b82577e59f23484c99056c96465e202fdd5 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Wed, 25 Apr 2012 13:39:38 +0200 Subject: i2c: mxs: disable QUEUE when sending is done Since the last fixes to this driver ensure now the queue termination is done correctly, we can finally disable the queue after a transfer without problems. The gain is that it will only be reenabled after the next transfer is fully set up. Before, the queue was running all the time and if the setup of the next message was interrupted by another thread, an incomplete buffer could have been sent, padded with zeroes. Signed-off-by: Wolfram Sang --- drivers/i2c/busses/i2c-mxs.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c index 4c37347973e..76b8af44f63 100644 --- a/drivers/i2c/busses/i2c-mxs.c +++ b/drivers/i2c/busses/i2c-mxs.c @@ -253,6 +253,9 @@ static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, if (i2c->cmd_err == -ENXIO) mxs_i2c_reset(i2c); + else + writel(MXS_I2C_QUEUECTRL_QUEUE_RUN, + i2c->regs + MXS_I2C_QUEUECTRL_CLR); dev_dbg(i2c->dev, "Done with err=%d\n", i2c->cmd_err); @@ -383,8 +386,6 @@ static int __devexit mxs_i2c_remove(struct platform_device *pdev) if (ret) return -EBUSY; - writel(MXS_I2C_QUEUECTRL_QUEUE_RUN, - i2c->regs + MXS_I2C_QUEUECTRL_CLR); writel(MXS_I2C_CTRL0_SFTRST, i2c->regs + MXS_I2C_CTRL0_SET); platform_set_drvdata(pdev, NULL); -- cgit v1.2.3-70-g09d2