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[PATCH 4/5] serial: 8250: omap: Support wakeup pinctrl state

Markus Schneider-Pargmann posted 5 patches 1 year, 8 months ago
There is a newer version of this series
[PATCH 4/5] serial: 8250: omap: Support wakeup pinctrl state
Posted by Markus Schneider-Pargmann 1 year, 8 months ago 
UART can be used as a wakeup source for am62 from a powered-off SoC
state. To enable wakeup from UART am62 requires a wakeup flag being set
in the pinctrl.

If the device is marked as wakeup enabled, select the 'wakeup' pinctrl
state on sys_off.

Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
---
 drivers/tty/serial/8250/8250_omap.c | 39 +++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
index 5b7508dfb5d8..617a421a1396 100644
--- a/drivers/tty/serial/8250/8250_omap.c
+++ b/drivers/tty/serial/8250/8250_omap.c
@@ -27,8 +27,10 @@
 #include <linux/pm_qos.h>
 #include <linux/pm_wakeirq.h>
 #include <linux/dma-mapping.h>
+#include <linux/reboot.h>
 #include <linux/sys_soc.h>
 #include <linux/pm_domain.h>
+#include <linux/pinctrl/consumer.h>
 
 #include "8250.h"
 
@@ -149,6 +151,9 @@ struct omap8250_priv {
 	spinlock_t rx_dma_lock;
 	bool rx_dma_broken;
 	bool throttled;
+
+	struct pinctrl *pinctrl;
+	struct pinctrl_state *pinctrl_wakeup;
 };
 
 struct omap8250_dma_params {
@@ -1345,6 +1350,30 @@ static int omap8250_no_handle_irq(struct uart_port *port)
 	return 0;
 }
 
+static int omap8250_select_wakeup_pinctrl(struct device *dev,
+					  struct omap8250_priv *priv)
+{
+	if (IS_ERR_OR_NULL(priv->pinctrl_wakeup))
+		return 0;
+
+	if (!device_may_wakeup(dev))
+		return 0;
+
+	return pinctrl_select_state(priv->pinctrl, priv->pinctrl_wakeup);
+}
+
+static int omap8250_sysoff_handler(struct sys_off_data *data)
+{
+	struct omap8250_priv *priv = dev_get_drvdata(data->dev);
+	int ret;
+
+	ret = omap8250_select_wakeup_pinctrl(data->dev, priv);
+	if (ret)
+		dev_err(data->dev, "Failed to select pinctrl state 'wakeup', continuing poweroff\n");
+
+	return NOTIFY_DONE;
+}
+
 static struct omap8250_dma_params am654_dma = {
 	.rx_size = SZ_2K,
 	.rx_trigger = 1,
@@ -1566,6 +1595,16 @@ static int omap8250_probe(struct platform_device *pdev)
 	priv->line = ret;
 	pm_runtime_mark_last_busy(&pdev->dev);
 	pm_runtime_put_autosuspend(&pdev->dev);
+
+	priv->pinctrl = devm_pinctrl_get(&pdev->dev);
+	if (!IS_ERR_OR_NULL(priv->pinctrl))
+		priv->pinctrl_wakeup = pinctrl_lookup_state(priv->pinctrl, "wakeup");
+
+	devm_register_sys_off_handler(&pdev->dev,
+				      SYS_OFF_MODE_POWER_OFF_PREPARE,
+				      SYS_OFF_PRIO_DEFAULT,
+				      omap8250_sysoff_handler, NULL);
+
 	return 0;
 err:
 	pm_runtime_dont_use_autosuspend(&pdev->dev);
-- 
2.43.0
Re: [PATCH 4/5] serial: 8250: omap: Support wakeup pinctrl state
Posted by Kevin Hilman 1 year, 6 months ago 
Markus Schneider-Pargmann <msp@baylibre.com> writes:

> UART can be used as a wakeup source for am62 from a powered-off SoC

nit: To be a bit more precise, instead of saying UART can be used as a
wakeup source, I think you should say:

Certain UART pins can be used...

> state. To enable wakeup from UART am62 requires a wakeup flag being set
> in the pinctrl.
>
> If the device is marked as wakeup enabled, select the 'wakeup' pinctrl
> state on sys_off.
>
> Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>

Reviewed-by: Kevin Hilman <khilman@baylibre.com>

> ---
>  drivers/tty/serial/8250/8250_omap.c | 39 +++++++++++++++++++++++++++++
>  1 file changed, 39 insertions(+)
>
> diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c
> index 5b7508dfb5d8..617a421a1396 100644
> --- a/drivers/tty/serial/8250/8250_omap.c
> +++ b/drivers/tty/serial/8250/8250_omap.c
> @@ -27,8 +27,10 @@
>  #include <linux/pm_qos.h>
>  #include <linux/pm_wakeirq.h>
>  #include <linux/dma-mapping.h>
> +#include <linux/reboot.h>
>  #include <linux/sys_soc.h>
>  #include <linux/pm_domain.h>
> +#include <linux/pinctrl/consumer.h>
>  
>  #include "8250.h"
>  
> @@ -149,6 +151,9 @@ struct omap8250_priv {
>  	spinlock_t rx_dma_lock;
>  	bool rx_dma_broken;
>  	bool throttled;
> +
> +	struct pinctrl *pinctrl;
> +	struct pinctrl_state *pinctrl_wakeup;
>  };
>  
>  struct omap8250_dma_params {
> @@ -1345,6 +1350,30 @@ static int omap8250_no_handle_irq(struct uart_port *port)
>  	return 0;
>  }
>  
> +static int omap8250_select_wakeup_pinctrl(struct device *dev,
> +					  struct omap8250_priv *priv)
> +{
> +	if (IS_ERR_OR_NULL(priv->pinctrl_wakeup))
> +		return 0;
> +
> +	if (!device_may_wakeup(dev))
> +		return 0;
> +
> +	return pinctrl_select_state(priv->pinctrl, priv->pinctrl_wakeup);
> +}
> +
> +static int omap8250_sysoff_handler(struct sys_off_data *data)
> +{
> +	struct omap8250_priv *priv = dev_get_drvdata(data->dev);
> +	int ret;
> +
> +	ret = omap8250_select_wakeup_pinctrl(data->dev, priv);
> +	if (ret)
> +		dev_err(data->dev, "Failed to select pinctrl state 'wakeup', continuing poweroff\n");
> +
> +	return NOTIFY_DONE;
> +}
> +
>  static struct omap8250_dma_params am654_dma = {
>  	.rx_size = SZ_2K,
>  	.rx_trigger = 1,
> @@ -1566,6 +1595,16 @@ static int omap8250_probe(struct platform_device *pdev)
>  	priv->line = ret;
>  	pm_runtime_mark_last_busy(&pdev->dev);
>  	pm_runtime_put_autosuspend(&pdev->dev);
> +
> +	priv->pinctrl = devm_pinctrl_get(&pdev->dev);
> +	if (!IS_ERR_OR_NULL(priv->pinctrl))
> +		priv->pinctrl_wakeup = pinctrl_lookup_state(priv->pinctrl, "wakeup");
> +
> +	devm_register_sys_off_handler(&pdev->dev,
> +				      SYS_OFF_MODE_POWER_OFF_PREPARE,
> +				      SYS_OFF_PRIO_DEFAULT,
> +				      omap8250_sysoff_handler, NULL);
> +
>  	return 0;
>  err:
>  	pm_runtime_dont_use_autosuspend(&pdev->dev);
> -- 
> 2.43.0
Re: [PATCH 4/5] serial: 8250: omap: Support wakeup pinctrl state
Posted by Andy Shevchenko 1 year, 8 months ago 
On Thu, May 23, 2024 at 09:58:18AM +0200, Markus Schneider-Pargmann wrote:
> UART can be used as a wakeup source for am62 from a powered-off SoC
> state. To enable wakeup from UART am62 requires a wakeup flag being set
> in the pinctrl.
> 
> If the device is marked as wakeup enabled, select the 'wakeup' pinctrl
> state on sys_off.

...

>  #include <linux/pm_qos.h>
>  #include <linux/pm_wakeirq.h>
>  #include <linux/dma-mapping.h>

> +#include <linux/reboot.h>

See below.

>  #include <linux/sys_soc.h>
>  #include <linux/pm_domain.h>

> +#include <linux/pinctrl/consumer.h>

Can we make some order here and put this before above pm_*.h or even earlier
according to the alphabet?

...

> +	priv->pinctrl = devm_pinctrl_get(&pdev->dev);
> +	if (!IS_ERR_OR_NULL(priv->pinctrl))

Shouldn't we report an error to the user? I assume that NULL is for optional
pin control, otherwise it's an error state which at bare minimum has to be
reported.

> +		priv->pinctrl_wakeup = pinctrl_lookup_state(priv->pinctrl, "wakeup");

> +	devm_register_sys_off_handler(&pdev->dev,

No error check?

> +				      SYS_OFF_MODE_POWER_OFF_PREPARE,
> +				      SYS_OFF_PRIO_DEFAULT,
> +				      omap8250_sysoff_handler, NULL);
> +

-- 
With Best Regards,
Andy Shevchenko

Patchew 2.1-devel-b67e4c2

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