From: Thierry Reding <thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> To: Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org> Cc: Dmitry Osipenko <digetx-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Jon Hunter <jonathanh-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>, linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Subject: [PATCH 2/5] i2c: tegra: Restore pinmux on system resume Date: Wed, 6 May 2020 21:33:55 +0200 [thread overview] Message-ID: <20200506193358.2807244-3-thierry.reding@gmail.com> (raw) In-Reply-To: <20200506193358.2807244-1-thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> From: Thierry Reding <treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> Depending on the board design, the I2C controllers found on Tegra SoCs may require pinmuxing in order to function. This is done as part of the driver's runtime suspend/resume operations. However, the PM core does not allow devices to go into runtime suspend during system sleep to avoid potential races with the suspend/resume of their parents. As a result of this, when Tegra SoCs resume from system suspend, their I2C controllers may have lost the pinmux state in hardware, whereas the pinctrl subsystem is not aware of this. To fix this, make sure that if the I2C controller is not runtime suspended, the runtime suspend code is still executed in order to disable the module clock (which we don't need to be enabled during sleep) and set the pinmux to the idle state. Conversely, make sure that the I2C controller is properly resumed when waking up from sleep so that pinmux settings are properly restored. This fixes a bug seen with DDC transactions to an HDMI monitor timing out when resuming from system suspend. Signed-off-by: Thierry Reding <treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> --- drivers/i2c/busses/i2c-tegra.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 7c88611c732c..db142d897604 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -1769,10 +1769,14 @@ static int tegra_i2c_remove(struct platform_device *pdev) static int __maybe_unused tegra_i2c_suspend(struct device *dev) { struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int err = 0; i2c_mark_adapter_suspended(&i2c_dev->adapter); - return 0; + if (!pm_runtime_status_suspended(dev)) + err = tegra_i2c_runtime_suspend(dev); + + return err; } static int __maybe_unused tegra_i2c_resume(struct device *dev) @@ -1788,9 +1792,11 @@ static int __maybe_unused tegra_i2c_resume(struct device *dev) if (err) return err; - err = tegra_i2c_runtime_suspend(dev); - if (err) - return err; + if (pm_runtime_status_suspended(dev)) { + err = tegra_i2c_runtime_suspend(dev); + if (err) + return err; + } i2c_mark_adapter_resumed(&i2c_dev->adapter); -- 2.24.1
WARNING: multiple messages have this Message-ID (diff)
From: Thierry Reding <thierry.reding@gmail.com> To: Wolfram Sang <wsa@the-dreams.de> Cc: Dmitry Osipenko <digetx@gmail.com>, Jon Hunter <jonathanh@nvidia.com>, linux-i2c@vger.kernel.org, linux-tegra@vger.kernel.org Subject: [PATCH 2/5] i2c: tegra: Restore pinmux on system resume Date: Wed, 6 May 2020 21:33:55 +0200 [thread overview] Message-ID: <20200506193358.2807244-3-thierry.reding@gmail.com> (raw) In-Reply-To: <20200506193358.2807244-1-thierry.reding@gmail.com> From: Thierry Reding <treding@nvidia.com> Depending on the board design, the I2C controllers found on Tegra SoCs may require pinmuxing in order to function. This is done as part of the driver's runtime suspend/resume operations. However, the PM core does not allow devices to go into runtime suspend during system sleep to avoid potential races with the suspend/resume of their parents. As a result of this, when Tegra SoCs resume from system suspend, their I2C controllers may have lost the pinmux state in hardware, whereas the pinctrl subsystem is not aware of this. To fix this, make sure that if the I2C controller is not runtime suspended, the runtime suspend code is still executed in order to disable the module clock (which we don't need to be enabled during sleep) and set the pinmux to the idle state. Conversely, make sure that the I2C controller is properly resumed when waking up from sleep so that pinmux settings are properly restored. This fixes a bug seen with DDC transactions to an HDMI monitor timing out when resuming from system suspend. Signed-off-by: Thierry Reding <treding@nvidia.com> --- drivers/i2c/busses/i2c-tegra.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 7c88611c732c..db142d897604 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -1769,10 +1769,14 @@ static int tegra_i2c_remove(struct platform_device *pdev) static int __maybe_unused tegra_i2c_suspend(struct device *dev) { struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev); + int err = 0; i2c_mark_adapter_suspended(&i2c_dev->adapter); - return 0; + if (!pm_runtime_status_suspended(dev)) + err = tegra_i2c_runtime_suspend(dev); + + return err; } static int __maybe_unused tegra_i2c_resume(struct device *dev) @@ -1788,9 +1792,11 @@ static int __maybe_unused tegra_i2c_resume(struct device *dev) if (err) return err; - err = tegra_i2c_runtime_suspend(dev); - if (err) - return err; + if (pm_runtime_status_suspended(dev)) { + err = tegra_i2c_runtime_suspend(dev); + if (err) + return err; + } i2c_mark_adapter_resumed(&i2c_dev->adapter); -- 2.24.1
next prev parent reply other threads:[~2020-05-06 19:33 UTC|newest] Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-05-06 19:33 [PATCH 0/5] i2c: tegra: Various fixes and improvements Thierry Reding 2020-05-06 19:33 ` Thierry Reding [not found] ` <20200506193358.2807244-1-thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> 2020-05-06 19:33 ` [PATCH 1/5] Revert "i2c: tegra: Fix suspending in active runtime PM state" Thierry Reding 2020-05-06 19:33 ` Thierry Reding 2020-05-06 19:33 ` Thierry Reding [this message] 2020-05-06 19:33 ` [PATCH 2/5] i2c: tegra: Restore pinmux on system resume Thierry Reding [not found] ` <20200506193358.2807244-3-thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> 2020-05-06 22:43 ` mirq-test-CoA6ZxLDdyEEUmgCuDUIdw 2020-05-06 22:43 ` mirq-test [not found] ` <20200506224336.GA23423-cHozx32mtrEEUmgCuDUIdw@public.gmane.org> 2020-05-07 10:03 ` Thierry Reding 2020-05-07 10:03 ` Thierry Reding 2020-05-07 12:20 ` Michał Mirosław 2020-05-07 12:20 ` Michał Mirosław 2020-05-07 21:50 ` Dmitry Osipenko 2020-05-07 21:50 ` Dmitry Osipenko [not found] ` <2a0404ac-73bf-2f27-9147-8bef28ae995f-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> 2020-05-08 10:31 ` Thierry Reding 2020-05-08 10:31 ` Thierry Reding 2020-05-08 15:00 ` Dmitry Osipenko 2020-05-08 15:00 ` Dmitry Osipenko [not found] ` <f149bb64-e93b-364e-47bc-c851e9638a35-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> 2020-05-09 15:35 ` Dmitry Osipenko 2020-05-09 15:35 ` Dmitry Osipenko [not found] ` <86fee5a3-fe2f-05ab-bc05-1c441d2845e9-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> 2020-05-19 16:07 ` Thierry Reding 2020-05-19 16:07 ` Thierry Reding 2020-05-19 15:57 ` Thierry Reding 2020-05-19 15:57 ` Thierry Reding 2020-05-08 15:05 ` Dmitry Osipenko 2020-05-08 15:05 ` Dmitry Osipenko 2020-05-06 19:33 ` [PATCH 3/5] i2c: tegra: Keep IRQs enabled during suspend/resume Thierry Reding 2020-05-06 19:33 ` Thierry Reding 2020-05-06 19:33 ` [PATCH 4/5] i2c: tegra: Better handle case where CPU0 is busy for a long time Thierry Reding 2020-05-06 19:33 ` Thierry Reding 2020-05-06 19:33 ` [PATCH 5/5] i2c: tegra: Synchronize DMA before termination Thierry Reding 2020-05-06 19:33 ` Thierry Reding
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