[V3,4/4] pwm: tegra: Add support to configure pin state in suspends/resume

Submitted by Laxman Dewangan on April 7, 2017, 9:34 a.m.

Details

Message ID 1491557642-15940-5-git-send-email-ldewangan@nvidia.com
State New
Headers show

Commit Message

Laxman Dewangan April 7, 2017, 9:34 a.m.
In some of NVIDIA Tegra's platform, PWM controller is used to
control the PWM controlled regulators. PWM signal is connected to
the VID pin of the regulator where duty cycle of PWM signal decide
the voltage level of the regulator output.

When system enters suspend, some PWM client/slave regulator devices
require the PWM output to be tristated.

Add support to configure the pin state via pinctrl frameworks in
suspend and active state of the system.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>

---
Changes from v1:
- Use standard pinctrl names for sleep and active state.
- Use API pinctrl_pm_select_*()

Changes from V2:
- Use returns of pinctrl_pm_select_*()
- Rephrase commit message.
---
 drivers/pwm/pwm-tegra.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

Comments

Jon Hunter April 7, 2017, 10:27 a.m.
On 07/04/17 10:34, Laxman Dewangan wrote:
> In some of NVIDIA Tegra's platform, PWM controller is used to
> control the PWM controlled regulators. PWM signal is connected to
> the VID pin of the regulator where duty cycle of PWM signal decide
> the voltage level of the regulator output.
> 
> When system enters suspend, some PWM client/slave regulator devices
> require the PWM output to be tristated.
> 
> Add support to configure the pin state via pinctrl frameworks in
> suspend and active state of the system.
> 
> Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
> 
> ---
> Changes from v1:
> - Use standard pinctrl names for sleep and active state.
> - Use API pinctrl_pm_select_*()
> 
> Changes from V2:
> - Use returns of pinctrl_pm_select_*()
> - Rephrase commit message.
> ---
>  drivers/pwm/pwm-tegra.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c
> index 21518be..9c7f180 100644
> --- a/drivers/pwm/pwm-tegra.c
> +++ b/drivers/pwm/pwm-tegra.c
> @@ -29,6 +29,7 @@
>  #include <linux/of_device.h>
>  #include <linux/pwm.h>
>  #include <linux/platform_device.h>
> +#include <linux/pinctrl/consumer.h>
>  #include <linux/slab.h>
>  #include <linux/reset.h>
>  
> @@ -255,6 +256,18 @@ static int tegra_pwm_remove(struct platform_device *pdev)
>  	return pwmchip_remove(&pc->chip);
>  }
>  
> +#ifdef CONFIG_PM_SLEEP
> +static int tegra_pwm_suspend(struct device *dev)
> +{
> +	return pinctrl_pm_select_sleep_state(dev);
> +}
> +
> +static int tegra_pwm_resume(struct device *dev)
> +{
> +	return pinctrl_pm_select_default_state(dev);
> +}
> +#endif
> +
>  static const struct tegra_pwm_soc tegra20_pwm_soc = {
>  	.num_channels = 4,
>  };
> @@ -271,10 +284,15 @@ static const struct of_device_id tegra_pwm_of_match[] = {
>  
>  MODULE_DEVICE_TABLE(of, tegra_pwm_of_match);
>  
> +static const struct dev_pm_ops tegra_pwm_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(tegra_pwm_suspend, tegra_pwm_resume)
> +};
> +
>  static struct platform_driver tegra_pwm_driver = {
>  	.driver = {
>  		.name = "tegra-pwm",
>  		.of_match_table = tegra_pwm_of_match,
> +		.pm = &tegra_pwm_pm_ops,
>  	},
>  	.probe = tegra_pwm_probe,
>  	.remove = tegra_pwm_remove,

Acked-by: Jon Hunter <jonathanh@nvidia.com>

Cheers
Jon

Patch hide | download patch | download mbox

diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c
index 21518be..9c7f180 100644
--- a/drivers/pwm/pwm-tegra.c
+++ b/drivers/pwm/pwm-tegra.c
@@ -29,6 +29,7 @@ 
 #include <linux/of_device.h>
 #include <linux/pwm.h>
 #include <linux/platform_device.h>
+#include <linux/pinctrl/consumer.h>
 #include <linux/slab.h>
 #include <linux/reset.h>
 
@@ -255,6 +256,18 @@  static int tegra_pwm_remove(struct platform_device *pdev)
 	return pwmchip_remove(&pc->chip);
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int tegra_pwm_suspend(struct device *dev)
+{
+	return pinctrl_pm_select_sleep_state(dev);
+}
+
+static int tegra_pwm_resume(struct device *dev)
+{
+	return pinctrl_pm_select_default_state(dev);
+}
+#endif
+
 static const struct tegra_pwm_soc tegra20_pwm_soc = {
 	.num_channels = 4,
 };
@@ -271,10 +284,15 @@  static const struct of_device_id tegra_pwm_of_match[] = {
 
 MODULE_DEVICE_TABLE(of, tegra_pwm_of_match);
 
+static const struct dev_pm_ops tegra_pwm_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(tegra_pwm_suspend, tegra_pwm_resume)
+};
+
 static struct platform_driver tegra_pwm_driver = {
 	.driver = {
 		.name = "tegra-pwm",
 		.of_match_table = tegra_pwm_of_match,
+		.pm = &tegra_pwm_pm_ops,
 	},
 	.probe = tegra_pwm_probe,
 	.remove = tegra_pwm_remove,