2020-06-29 18:50:12

by Prashant Malani

[permalink] [raw]
Subject: [PATCH v2 1/2] platform/chrome: cros_ec_typec: Use workqueue for port update

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 <[email protected]>
---

Changes in v2:
- No changes.

drivers/platform/chrome/cros_ec_typec.c | 28 ++++++++++++++++++++-----
1 file changed, 23 insertions(+), 5 deletions(-)

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index 0c041b79cbba..630170fb2cbe 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 +620,29 @@ 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 +701,12 @@ 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


2020-06-29 19:08:14

by Prashant Malani

[permalink] [raw]
Subject: Re: [PATCH v2 1/2] platform/chrome: cros_ec_typec: Use workqueue for port update

Hi Guenter,

Thanks for the review!

On Mon, Jun 29, 2020 at 9:24 AM Guenter Roeck <[email protected]> wrote:
>
> On Mon, Jun 29, 2020 at 9:13 AM Prashant Malani <[email protected]> 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 <[email protected]>
> > ---
> >
> > Changes in v2:
> > - No changes.
> >
> > drivers/platform/chrome/cros_ec_typec.c | 28 ++++++++++++++++++++-----
> > 1 file changed, 23 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
> > index 0c041b79cbba..630170fb2cbe 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 +620,29 @@ 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);
>
> Nit, but the upstream line length limit is now 100 characters, and
> this is a perfect example where this would come handy.

Done.
>
> > + 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);
> > +
> ... and even more so here.

Done.

>
> > + schedule_work(&typec->port_work);
> >
> > return NOTIFY_OK;
> > }
> > @@ -689,6 +701,12 @@ 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
> >

2020-06-29 21:21:36

by Guenter Roeck

[permalink] [raw]
Subject: Re: [PATCH v2 1/2] platform/chrome: cros_ec_typec: Use workqueue for port update

On Mon, Jun 29, 2020 at 9:13 AM Prashant Malani <[email protected]> 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 <[email protected]>
> ---
>
> Changes in v2:
> - No changes.
>
> drivers/platform/chrome/cros_ec_typec.c | 28 ++++++++++++++++++++-----
> 1 file changed, 23 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
> index 0c041b79cbba..630170fb2cbe 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 +620,29 @@ 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);

Nit, but the upstream line length limit is now 100 characters, and
this is a perfect example where this would come handy.

> + 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);
> +
... and even more so here.

> + schedule_work(&typec->port_work);
>
> return NOTIFY_OK;
> }
> @@ -689,6 +701,12 @@ 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
>

2020-06-29 21:29:07

by Prashant Malani

[permalink] [raw]
Subject: [PATCH v2 2/2] platform/chrome: cros_ec_typec: Add PM support

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 <[email protected]>
---

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

drivers/platform/chrome/cros_ec_typec.c | 26 +++++++++++++++++++++++++
1 file changed, 26 insertions(+)

diff --git a/drivers/platform/chrome/cros_ec_typec.c b/drivers/platform/chrome/cros_ec_typec.c
index 630170fb2cbe..b2e7e928e788 100644
--- a/drivers/platform/chrome/cros_ec_typec.c
+++ b/drivers/platform/chrome/cros_ec_typec.c
@@ -725,11 +725,37 @@ 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)
+};
+
+#define DEV_PM_OPS (&cros_typec_pm_ops)
+
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 = DEV_PM_OPS,
},
.probe = cros_typec_probe,
};
--
2.27.0.212.ge8ba1cc988-goog