[PATCH v3 1/2] platform/chrome: cros_ec_typec: Use workqueue for port update

[PATCH v3 1/2] platform/chrome: cros_ec_typec: Use workqueue for port update

[Prashant Malani]

Use a work queue to call the port update routines, instead of doing it
directly in the PD notifier callback. This will prevent other drivers
with PD notifier callbacks from being blocked on the port update routine
completing.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
---

Changes in v3:
- Use new 100 character line length limit.

Changes in v2:
- No changes.

 drivers/platform/chrome/cros_ec_typec.c | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index 0c041b79cbba..0beb62bf5adf 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -58,6 +58,7 @@ struct cros_typec_data {
 	/* Array of ports, indexed by port number. */
 	struct cros_typec_port *ports[EC_USB_PD_MAX_PORTS];
 	struct notifier_block nb;
+	struct work_struct port_work;
 };
 
 static int cros_typec_parse_port_props(struct typec_capability *cap,
@@ -619,18 +620,26 @@ static int cros_typec_get_cmd_version(struct cros_typec_data *typec)
 	return 0;
 }
 
-static int cros_ec_typec_event(struct notifier_block *nb,
-			       unsigned long host_event, void *_notify)
+static void cros_typec_port_work(struct work_struct *work)
 {
-	struct cros_typec_data *typec = container_of(nb, struct cros_typec_data,
-						     nb);
-	int ret, i;
+	struct cros_typec_data *typec = container_of(work, struct cros_typec_data, port_work);
+	int ret;
+	int i;
 
 	for (i = 0; i < typec->num_ports; i++) {
 		ret = cros_typec_port_update(typec, i);
 		if (ret < 0)
 			dev_warn(typec->dev, "Update failed for port: %d\n", i);
 	}
+}
+
+
+static int cros_ec_typec_event(struct notifier_block *nb,
+			       unsigned long host_event, void *_notify)
+{
+	struct cros_typec_data *typec = container_of(nb, struct cros_typec_data, nb);
+
+	schedule_work(&typec->port_work);
 
 	return NOTIFY_OK;
 }
@@ -689,6 +698,12 @@ static int cros_typec_probe(struct platform_device *pdev)
 	if (ret < 0)
 		return ret;
 
+	INIT_WORK(&typec->port_work, cros_typec_port_work);
+
+	/*
+	 * Safe to call port update here, since we haven't registered the
+	 * PD notifier yet.
+	 */
 	for (i = 0; i < typec->num_ports; i++) {
 		ret = cros_typec_port_update(typec, i);
 		if (ret < 0)
-- 
2.27.0.212.ge8ba1cc988-goog

[PATCH v3 2/2] platform/chrome: cros_ec_typec: Add PM support

[Prashant Malani]

Define basic suspend resume functions for cros-ec-typec. On suspend, we
simply ensure that any pending port update work is completed, and on
resume, we re-poll the port state to account for any
changes/disconnections that might have occurred during suspend.

Signed-off-by: Prashant Malani <pmalani@chromium.org>
---

Changes in v3:
- Remove superfluous DEV_PM_OPS #define.

Changes in v2:
- Remove #ifdef-ery, add __maybe_unused tag to functions.

 drivers/platform/chrome/cros_ec_typec.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index 0beb62bf5adf..d5ac691de68b 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -722,11 +722,35 @@ static int cros_typec_probe(struct platform_device *pdev)
 	return ret;
 }
 
+static int __maybe_unused cros_typec_suspend(struct device *dev)
+{
+	struct cros_typec_data *typec = dev_get_drvdata(dev);
+
+	cancel_work_sync(&typec->port_work);
+
+	return 0;
+}
+
+static int __maybe_unused cros_typec_resume(struct device *dev)
+{
+	struct cros_typec_data *typec = dev_get_drvdata(dev);
+
+	/* Refresh port state. */
+	schedule_work(&typec->port_work);
+
+	return 0;
+}
+
+static const struct dev_pm_ops cros_typec_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(cros_typec_suspend, cros_typec_resume)
+};
+
 static struct platform_driver cros_typec_driver = {
 	.driver	= {
 		.name = DRV_NAME,
 		.acpi_match_table = ACPI_PTR(cros_typec_acpi_id),
 		.of_match_table = of_match_ptr(cros_typec_of_match),
+		.pm = &cros_typec_pm_ops,
 	},
 	.probe = cros_typec_probe,
 };
-- 
2.27.0.212.ge8ba1cc988-goog

Re: [PATCH v3 1/2] platform/chrome: cros_ec_typec: Use workqueue for port update

[Guenter Roeck]

On Mon, Jun 29, 2020 at 9:38 AM Prashant Malani <pmalani@chromium.org> wrote:
>
> Use a work queue to call the port update routines, instead of doing it
> directly in the PD notifier callback. This will prevent other drivers
> with PD notifier callbacks from being blocked on the port update routine
> completing.
>
> Signed-off-by: Prashant Malani <pmalani@chromium.org>
> ---
>
> Changes in v3:
> - Use new 100 character line length limit.
>
> Changes in v2:
> - No changes.
>
>  drivers/platform/chrome/cros_ec_typec.c | 25 ++++++++++++++++++++-----
>  1 file changed, 20 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
> index 0c041b79cbba..0beb62bf5adf 100644
> --- a/drivers/platform/chrome/cros_ec_typec.c
> +++ b/drivers/platform/chrome/cros_ec_typec.c
> @@ -58,6 +58,7 @@ struct cros_typec_data {
>         /* Array of ports, indexed by port number. */
>         struct cros_typec_port *ports[EC_USB_PD_MAX_PORTS];
>         struct notifier_block nb;
> +       struct work_struct port_work;
>  };
>
>  static int cros_typec_parse_port_props(struct typec_capability *cap,
> @@ -619,18 +620,26 @@ static int cros_typec_get_cmd_version(struct cros_typec_data *typec)
>         return 0;
>  }
>
> -static int cros_ec_typec_event(struct notifier_block *nb,
> -                              unsigned long host_event, void *_notify)
> +static void cros_typec_port_work(struct work_struct *work)
>  {
> -       struct cros_typec_data *typec = container_of(nb, struct cros_typec_data,
> -                                                    nb);
> -       int ret, i;
> +       struct cros_typec_data *typec = container_of(work, struct cros_typec_data, port_work);
> +       int ret;
> +       int i;
>

I know I am getting picky here, but this seems like a personal
preference change. There is no "one variable declaration per line"
coding style rule.

>         for (i = 0; i < typec->num_ports; i++) {
>                 ret = cros_typec_port_update(typec, i);
>                 if (ret < 0)
>                         dev_warn(typec->dev, "Update failed for port: %d\n", i);
>         }
> +}
> +
> +

... but anyway, there should be no double empty lines.

> +static int cros_ec_typec_event(struct notifier_block *nb,
> +                              unsigned long host_event, void *_notify)
> +{
> +       struct cros_typec_data *typec = container_of(nb, struct cros_typec_data, nb);
> +
> +       schedule_work(&typec->port_work);
>
>         return NOTIFY_OK;
>  }
> @@ -689,6 +698,12 @@ static int cros_typec_probe(struct platform_device *pdev)
>         if (ret < 0)
>                 return ret;
>
> +       INIT_WORK(&typec->port_work, cros_typec_port_work);
> +
> +       /*
> +        * Safe to call port update here, since we haven't registered the
> +        * PD notifier yet.
> +        */
>         for (i = 0; i < typec->num_ports; i++) {
>                 ret = cros_typec_port_update(typec, i);
>                 if (ret < 0)
> --
> 2.27.0.212.ge8ba1cc988-goog
>

Re: [PATCH v3 2/2] platform/chrome: cros_ec_typec: Add PM support

[Guenter Roeck]

On Mon, Jun 29, 2020 at 9:39 AM Prashant Malani <pmalani@chromium.org> wrote:
>
> Define basic suspend resume functions for cros-ec-typec. On suspend, we
> simply ensure that any pending port update work is completed, and on
> resume, we re-poll the port state to account for any
> changes/disconnections that might have occurred during suspend.
>
> Signed-off-by: Prashant Malani <pmalani@chromium.org>

Reviewed-by: Guenter Roeck <groeck@chromium.org>

> ---
>
> Changes in v3:
> - Remove superfluous DEV_PM_OPS #define.
>
> Changes in v2:
> - Remove #ifdef-ery, add __maybe_unused tag to functions.
>
>  drivers/platform/chrome/cros_ec_typec.c | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
>
> diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
> index 0beb62bf5adf..d5ac691de68b 100644
> --- a/drivers/platform/chrome/cros_ec_typec.c
> +++ b/drivers/platform/chrome/cros_ec_typec.c
> @@ -722,11 +722,35 @@ static int cros_typec_probe(struct platform_device *pdev)
>         return ret;
>  }
>
> +static int __maybe_unused cros_typec_suspend(struct device *dev)
> +{
> +       struct cros_typec_data *typec = dev_get_drvdata(dev);
> +
> +       cancel_work_sync(&typec->port_work);
> +
> +       return 0;
> +}
> +
> +static int __maybe_unused cros_typec_resume(struct device *dev)
> +{
> +       struct cros_typec_data *typec = dev_get_drvdata(dev);
> +
> +       /* Refresh port state. */
> +       schedule_work(&typec->port_work);
> +
> +       return 0;
> +}
> +
> +static const struct dev_pm_ops cros_typec_pm_ops = {
> +       SET_SYSTEM_SLEEP_PM_OPS(cros_typec_suspend, cros_typec_resume)
> +};
> +
>  static struct platform_driver cros_typec_driver = {
>         .driver = {
>                 .name = DRV_NAME,
>                 .acpi_match_table = ACPI_PTR(cros_typec_acpi_id),
>                 .of_match_table = of_match_ptr(cros_typec_of_match),
> +               .pm = &cros_typec_pm_ops,
>         },
>         .probe = cros_typec_probe,
>  };
> --
> 2.27.0.212.ge8ba1cc988-goog
>

Re: [PATCH v3 1/2] platform/chrome: cros_ec_typec: Use workqueue for port update

[Prashant Malani]

Hi Guenter,

Thanks for the comments.

On Mon, Jun 29, 2020 at 2:05 PM Guenter Roeck <groeck@google.com> wrote:
>
> On Mon, Jun 29, 2020 at 9:38 AM Prashant Malani <pmalani@chromium.org> wrote:
> >
> > Use a work queue to call the port update routines, instead of doing it
> > directly in the PD notifier callback. This will prevent other drivers
> > with PD notifier callbacks from being blocked on the port update routine
> > completing.
> >
> > Signed-off-by: Prashant Malani <pmalani@chromium.org>
> > ---
> >
> > Changes in v3:
> > - Use new 100 character line length limit.
> >
> > Changes in v2:
> > - No changes.
> >
> >  drivers/platform/chrome/cros_ec_typec.c | 25 ++++++++++++++++++++-----
> >  1 file changed, 20 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
> > index 0c041b79cbba..0beb62bf5adf 100644
> > --- a/drivers/platform/chrome/cros_ec_typec.c
> > +++ b/drivers/platform/chrome/cros_ec_typec.c
> > @@ -58,6 +58,7 @@ struct cros_typec_data {
> >         /* Array of ports, indexed by port number. */
> >         struct cros_typec_port *ports[EC_USB_PD_MAX_PORTS];
> >         struct notifier_block nb;
> > +       struct work_struct port_work;
> >  };
> >
> >  static int cros_typec_parse_port_props(struct typec_capability *cap,
> > @@ -619,18 +620,26 @@ static int cros_typec_get_cmd_version(struct cros_typec_data *typec)
> >         return 0;
> >  }
> >
> > -static int cros_ec_typec_event(struct notifier_block *nb,
> > -                              unsigned long host_event, void *_notify)
> > +static void cros_typec_port_work(struct work_struct *work)
> >  {
> > -       struct cros_typec_data *typec = container_of(nb, struct cros_typec_data,
> > -                                                    nb);
> > -       int ret, i;
> > +       struct cros_typec_data *typec = container_of(work, struct cros_typec_data, port_work);
> > +       int ret;
> > +       int i;
> >
>
> I know I am getting picky here, but this seems like a personal
> preference change. There is no "one variable declaration per line"
> coding style rule.

Done.
>
> >         for (i = 0; i < typec->num_ports; i++) {
> >                 ret = cros_typec_port_update(typec, i);
> >                 if (ret < 0)
> >                         dev_warn(typec->dev, "Update failed for port: %d\n", i);
> >         }
> > +}
> > +
> > +
>
> ... but anyway, there should be no double empty lines.
>

Done.
> > +static int cros_ec_typec_event(struct notifier_block *nb,
> > +                              unsigned long host_event, void *_notify)
> > +{
> > +       struct cros_typec_data *typec = container_of(nb, struct cros_typec_data, nb);
> > +
> > +       schedule_work(&typec->port_work);
> >
> >         return NOTIFY_OK;
> >  }
> > @@ -689,6 +698,12 @@ static int cros_typec_probe(struct platform_device *pdev)
> >         if (ret < 0)
> >                 return ret;
> >
> > +       INIT_WORK(&typec->port_work, cros_typec_port_work);
> > +
> > +       /*
> > +        * Safe to call port update here, since we haven't registered the
> > +        * PD notifier yet.
> > +        */
> >         for (i = 0; i < typec->num_ports; i++) {
> >                 ret = cros_typec_port_update(typec, i);
> >                 if (ret < 0)
> > --
> > 2.27.0.212.ge8ba1cc988-goog
> >