[PATCH v5 0/3] usb: typec: ucsi: allow retry to find role switch

[PATCH v5 0/3] usb: typec: ucsi: allow retry to find role switch

[Linyu Yuan]

when one role switch module built as module, it may load late than
ucsi, this change series allow retry from ucsi.

v2: improve ucsi_connector_clean() to cover all condition,
    and add one new change to avoid allocate one unused connector.

v3: fix comment from ucsi maintainer.

v4: fix review comment from Heikki Krogerus,
    merge patch#1 and patch#2 in V3 into one patch,
    add counter for retry limit,
    and some other minor fix.

v5: only update commit description of two patches

Linyu Yuan (3):
  usb: typec: ucsi: add a common function ucsi_unregister_connectors()
  usb: typec: ucsi: do not allocate one extra unused connector
  usb: typec: ucsi: Wait for the USB role switches

 drivers/usb/typec/ucsi/ucsi.c | 86 +++++++++++++++++++++++++------------------
 drivers/usb/typec/ucsi/ucsi.h |  6 ++-
 2 files changed, 55 insertions(+), 37 deletions(-)

-- 
2.7.4

[PATCH v5 1/3] usb: typec: ucsi: add a common function ucsi_unregister_connectors()

[Linyu Yuan]

As con->port will be used in error path of ucsi_init(),
it should be NULL or valid.

In error path of ucsi_init(), it will unregister all valid ucsi connectors,
and similar operation also happen in ucsi_unregister(),
add a common function for two places.

Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
---
v2: improve ucsi_connector_clean(), check total number of connector.
v3: rename to ucsi_unregister_connectors(), suggest by maintainer
v4: merge patch#1 in V3, fix a typo samiliar -> similar in commit description
v5: no change

 drivers/usb/typec/ucsi/ucsi.c | 52 ++++++++++++++++++++++++-------------------
 1 file changed, 29 insertions(+), 23 deletions(-)

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index f0c2fa1..af9a2a1 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -1100,6 +1100,7 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
 	con->port = typec_register_port(ucsi->dev, cap);
 	if (IS_ERR(con->port)) {
 		ret = PTR_ERR(con->port);
+		con->port = NULL;
 		goto out;
 	}
 
@@ -1186,6 +1187,32 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
 	return ret;
 }
 
+static void ucsi_unregister_connectors(struct ucsi *ucsi)
+{
+	struct ucsi_connector *con;
+	int i;
+
+	if (!ucsi->connector)
+		return;
+
+	for (i = 0; i < ucsi->cap.num_connectors; i++) {
+		con = &ucsi->connector[i];
+		if (!con->port)
+			break;
+
+		cancel_work_sync(&con->work);
+		ucsi_unregister_partner(con);
+		ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON);
+		ucsi_unregister_port_psy(con);
+		if (con->wq)
+			destroy_workqueue(con->wq);
+		typec_unregister_port(con->port);
+	}
+
+	kfree(ucsi->connector);
+	ucsi->connector = NULL;
+}
+
 /**
  * ucsi_init - Initialize UCSI interface
  * @ucsi: UCSI to be initialized
@@ -1194,7 +1221,6 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
  */
 static int ucsi_init(struct ucsi *ucsi)
 {
-	struct ucsi_connector *con;
 	u64 command;
 	int ret;
 	int i;
@@ -1249,15 +1275,7 @@ static int ucsi_init(struct ucsi *ucsi)
 	return 0;
 
 err_unregister:
-	for (con = ucsi->connector; con->port; con++) {
-		ucsi_unregister_partner(con);
-		ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON);
-		ucsi_unregister_port_psy(con);
-		if (con->wq)
-			destroy_workqueue(con->wq);
-		typec_unregister_port(con->port);
-		con->port = NULL;
-	}
+	ucsi_unregister_connectors(ucsi);
 
 err_reset:
 	memset(&ucsi->cap, 0, sizeof(ucsi->cap));
@@ -1363,7 +1381,6 @@ EXPORT_SYMBOL_GPL(ucsi_register);
 void ucsi_unregister(struct ucsi *ucsi)
 {
 	u64 cmd = UCSI_SET_NOTIFICATION_ENABLE;
-	int i;
 
 	/* Make sure that we are not in the middle of driver initialization */
 	cancel_work_sync(&ucsi->work);
@@ -1371,18 +1388,7 @@ void ucsi_unregister(struct ucsi *ucsi)
 	/* Disable notifications */
 	ucsi->ops->async_write(ucsi, UCSI_CONTROL, &cmd, sizeof(cmd));
 
-	for (i = 0; i < ucsi->cap.num_connectors; i++) {
-		cancel_work_sync(&ucsi->connector[i].work);
-		ucsi_unregister_partner(&ucsi->connector[i]);
-		ucsi_unregister_altmodes(&ucsi->connector[i],
-					 UCSI_RECIPIENT_CON);
-		ucsi_unregister_port_psy(&ucsi->connector[i]);
-		if (ucsi->connector[i].wq)
-			destroy_workqueue(ucsi->connector[i].wq);
-		typec_unregister_port(ucsi->connector[i].port);
-	}
-
-	kfree(ucsi->connector);
+	ucsi_unregister_connectors(ucsi);
 }
 EXPORT_SYMBOL_GPL(ucsi_unregister);
 
-- 
2.7.4

Re: [PATCH v5 1/3] usb: typec: ucsi: add a common function ucsi_unregister_connectors()

[Heikki Krogerus]

On Fri, Apr 22, 2022 at 11:10:20AM +0800, Linyu Yuan wrote:
> As con->port will be used in error path of ucsi_init(),
> it should be NULL or valid.
> 
> In error path of ucsi_init(), it will unregister all valid ucsi connectors,
> and similar operation also happen in ucsi_unregister(),
> add a common function for two places.
> 
> Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
> ---
> v2: improve ucsi_connector_clean(), check total number of connector.
> v3: rename to ucsi_unregister_connectors(), suggest by maintainer
> v4: merge patch#1 in V3, fix a typo samiliar -> similar in commit description
> v5: no change
> 
>  drivers/usb/typec/ucsi/ucsi.c | 52 ++++++++++++++++++++++++-------------------
>  1 file changed, 29 insertions(+), 23 deletions(-)
> 
> diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
> index f0c2fa1..af9a2a1 100644
> --- a/drivers/usb/typec/ucsi/ucsi.c
> +++ b/drivers/usb/typec/ucsi/ucsi.c
> @@ -1100,6 +1100,7 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
>  	con->port = typec_register_port(ucsi->dev, cap);
>  	if (IS_ERR(con->port)) {
>  		ret = PTR_ERR(con->port);
> +		con->port = NULL;

I'm not sure you need to add that line. See below.

>  		goto out;
>  	}
>  
> @@ -1186,6 +1187,32 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
>  	return ret;
>  }
>  
> +static void ucsi_unregister_connectors(struct ucsi *ucsi)
> +{
> +	struct ucsi_connector *con;
> +	int i;
> +
> +	if (!ucsi->connector)
> +		return;
> +
> +	for (i = 0; i < ucsi->cap.num_connectors; i++) {
> +		con = &ucsi->connector[i];
> +		if (!con->port)
> +			break;

                if (IS_ERR_OR_NULL(con->port))
                        break;

> +		cancel_work_sync(&con->work);
> +		ucsi_unregister_partner(con);
> +		ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON);
> +		ucsi_unregister_port_psy(con);
> +		if (con->wq)
> +			destroy_workqueue(con->wq);
> +		typec_unregister_port(con->port);
> +	}
> +
> +	kfree(ucsi->connector);
> +	ucsi->connector = NULL;
> +}
> +
>  /**
>   * ucsi_init - Initialize UCSI interface
>   * @ucsi: UCSI to be initialized
> @@ -1194,7 +1221,6 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
>   */
>  static int ucsi_init(struct ucsi *ucsi)
>  {
> -	struct ucsi_connector *con;
>  	u64 command;
>  	int ret;
>  	int i;
> @@ -1249,15 +1275,7 @@ static int ucsi_init(struct ucsi *ucsi)
>  	return 0;
>  
>  err_unregister:
> -	for (con = ucsi->connector; con->port; con++) {
> -		ucsi_unregister_partner(con);
> -		ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON);
> -		ucsi_unregister_port_psy(con);
> -		if (con->wq)
> -			destroy_workqueue(con->wq);
> -		typec_unregister_port(con->port);
> -		con->port = NULL;
> -	}
> +	ucsi_unregister_connectors(ucsi);
>  
>  err_reset:
>  	memset(&ucsi->cap, 0, sizeof(ucsi->cap));
> @@ -1363,7 +1381,6 @@ EXPORT_SYMBOL_GPL(ucsi_register);
>  void ucsi_unregister(struct ucsi *ucsi)
>  {
>  	u64 cmd = UCSI_SET_NOTIFICATION_ENABLE;
> -	int i;
>  
>  	/* Make sure that we are not in the middle of driver initialization */
>  	cancel_work_sync(&ucsi->work);
> @@ -1371,18 +1388,7 @@ void ucsi_unregister(struct ucsi *ucsi)
>  	/* Disable notifications */
>  	ucsi->ops->async_write(ucsi, UCSI_CONTROL, &cmd, sizeof(cmd));
>  
> -	for (i = 0; i < ucsi->cap.num_connectors; i++) {
> -		cancel_work_sync(&ucsi->connector[i].work);
> -		ucsi_unregister_partner(&ucsi->connector[i]);
> -		ucsi_unregister_altmodes(&ucsi->connector[i],
> -					 UCSI_RECIPIENT_CON);
> -		ucsi_unregister_port_psy(&ucsi->connector[i]);
> -		if (ucsi->connector[i].wq)
> -			destroy_workqueue(ucsi->connector[i].wq);
> -		typec_unregister_port(ucsi->connector[i].port);
> -	}
> -
> -	kfree(ucsi->connector);
> +	ucsi_unregister_connectors(ucsi);
>  }
>  EXPORT_SYMBOL_GPL(ucsi_unregister);

thanks,

-- 
heikki

RE: [PATCH v5 1/3] usb: typec: ucsi: add a common function ucsi_unregister_connectors()

[Linyu Yuan (QUIC)]

> From: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> Sent: Monday, April 25, 2022 4:10 PM
> To: Linyu Yuan (QUIC) <quic_linyyuan@quicinc.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>; linux-
> usb@vger.kernel.org; Jack Pham (QUIC) <quic_jackp@quicinc.com>
> Subject: Re: [PATCH v5 1/3] usb: typec: ucsi: add a common function
> ucsi_unregister_connectors()
> 
> On Fri, Apr 22, 2022 at 11:10:20AM +0800, Linyu Yuan wrote:
> > As con->port will be used in error path of ucsi_init(),
> > it should be NULL or valid.
> >
> > In error path of ucsi_init(), it will unregister all valid ucsi connectors,
> > and similar operation also happen in ucsi_unregister(),
> > add a common function for two places.
> >
> > Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
> > ---
> > v2: improve ucsi_connector_clean(), check total number of connector.
> > v3: rename to ucsi_unregister_connectors(), suggest by maintainer
> > v4: merge patch#1 in V3, fix a typo samiliar -> similar in commit description
> > v5: no change
> >
> >  drivers/usb/typec/ucsi/ucsi.c | 52 ++++++++++++++++++++++++-----------
> --------
> >  1 file changed, 29 insertions(+), 23 deletions(-)
> >
> > diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
> > index f0c2fa1..af9a2a1 100644
> > --- a/drivers/usb/typec/ucsi/ucsi.c
> > +++ b/drivers/usb/typec/ucsi/ucsi.c
> > @@ -1100,6 +1100,7 @@ static int ucsi_register_port(struct ucsi *ucsi, int
> index)
> >  	con->port = typec_register_port(ucsi->dev, cap);
> >  	if (IS_ERR(con->port)) {
> >  		ret = PTR_ERR(con->port);
> > +		con->port = NULL;
> 
> I'm not sure you need to add that line. See below.
> 
> >  		goto out;
> >  	}
> >
> > @@ -1186,6 +1187,32 @@ static int ucsi_register_port(struct ucsi *ucsi, int
> index)
> >  	return ret;
> >  }
> >
> > +static void ucsi_unregister_connectors(struct ucsi *ucsi)
> > +{
> > +	struct ucsi_connector *con;
> > +	int i;
> > +
> > +	if (!ucsi->connector)
> > +		return;
> > +
> > +	for (i = 0; i < ucsi->cap.num_connectors; i++) {
> > +		con = &ucsi->connector[i];
> > +		if (!con->port)
> > +			break;
> 
>                 if (IS_ERR_OR_NULL(con->port))
>                         break;

Good suggestion, will change it next version.

> 
> thanks,
> 
> --
> heikki

[PATCH v5 2/3] usb: typec: ucsi: do not allocate one extra unused connector

[Linyu Yuan]

In ucsi_init(), it allocate number of (ucsi->cap.num_connectors + 1)
connectors, there is one extra as the ending.
ucsi_unregister_connectors() is safe to unregister all ucsi connectors
according ucsi->cap.num_connectors.

Let's remove the extra one connector to save memory.

Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
---
v2: new change
v3: no change
v4: fix a typo extral -> extra in commit description
v5: update commit description

 drivers/usb/typec/ucsi/ucsi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index af9a2a1..ce9192e 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -1251,7 +1251,7 @@ static int ucsi_init(struct ucsi *ucsi)
 	}
 
 	/* Allocate the connectors. Released in ucsi_unregister() */
-	ucsi->connector = kcalloc(ucsi->cap.num_connectors + 1,
+	ucsi->connector = kcalloc(ucsi->cap.num_connectors,
 				  sizeof(*ucsi->connector), GFP_KERNEL);
 	if (!ucsi->connector) {
 		ret = -ENOMEM;
-- 
2.7.4

Re: [PATCH v5 2/3] usb: typec: ucsi: do not allocate one extra unused connector

[Heikki Krogerus]

On Fri, Apr 22, 2022 at 11:10:21AM +0800, Linyu Yuan wrote:
> In ucsi_init(), it allocate number of (ucsi->cap.num_connectors + 1)
> connectors, there is one extra as the ending.
> ucsi_unregister_connectors() is safe to unregister all ucsi connectors
> according ucsi->cap.num_connectors.
> 
> Let's remove the extra one connector to save memory.

Maybe you could just merge this one into the first patch.

> Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
> ---
> v2: new change
> v3: no change
> v4: fix a typo extral -> extra in commit description
> v5: update commit description
> 
>  drivers/usb/typec/ucsi/ucsi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
> index af9a2a1..ce9192e 100644
> --- a/drivers/usb/typec/ucsi/ucsi.c
> +++ b/drivers/usb/typec/ucsi/ucsi.c
> @@ -1251,7 +1251,7 @@ static int ucsi_init(struct ucsi *ucsi)
>  	}
>  
>  	/* Allocate the connectors. Released in ucsi_unregister() */
> -	ucsi->connector = kcalloc(ucsi->cap.num_connectors + 1,
> +	ucsi->connector = kcalloc(ucsi->cap.num_connectors,
>  				  sizeof(*ucsi->connector), GFP_KERNEL);
>  	if (!ucsi->connector) {
>  		ret = -ENOMEM;
> -- 
> 2.7.4

thanks,

-- 
heikki

RE: [PATCH v5 2/3] usb: typec: ucsi: do not allocate one extra unused connector

[Linyu Yuan (QUIC)]

> From: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> Sent: Monday, April 25, 2022 4:14 PM
> To: Linyu Yuan (QUIC) <quic_linyyuan@quicinc.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>; linux-
> usb@vger.kernel.org; Jack Pham (QUIC) <quic_jackp@quicinc.com>
> Subject: Re: [PATCH v5 2/3] usb: typec: ucsi: do not allocate one extra
> unused connector
> 
> On Fri, Apr 22, 2022 at 11:10:21AM +0800, Linyu Yuan wrote:
> > In ucsi_init(), it allocate number of (ucsi->cap.num_connectors + 1)
> > connectors, there is one extra as the ending.
> > ucsi_unregister_connectors() is safe to unregister all ucsi connectors
> > according ucsi->cap.num_connectors.
> >
> > Let's remove the extra one connector to save memory.
> 
> Maybe you could just merge this one into the first patch.

Sure, thanks, will merge next version.

> 
> > Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
> > ---
> > v2: new change
> > v3: no change
> > v4: fix a typo extral -> extra in commit description
> > v5: update commit description
> >
> >  drivers/usb/typec/ucsi/ucsi.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
> > index af9a2a1..ce9192e 100644
> > --- a/drivers/usb/typec/ucsi/ucsi.c
> > +++ b/drivers/usb/typec/ucsi/ucsi.c
> > @@ -1251,7 +1251,7 @@ static int ucsi_init(struct ucsi *ucsi)
> >  	}
> >
> >  	/* Allocate the connectors. Released in ucsi_unregister() */
> > -	ucsi->connector = kcalloc(ucsi->cap.num_connectors + 1,
> > +	ucsi->connector = kcalloc(ucsi->cap.num_connectors,
> >  				  sizeof(*ucsi->connector), GFP_KERNEL);
> >  	if (!ucsi->connector) {
> >  		ret = -ENOMEM;
> > --
> > 2.7.4
> 
> thanks,
> 
> --
> heikki

[PATCH v5 3/3] usb: typec: ucsi: Wait for the USB role switches

[Linyu Yuan]

When role switch module probe late than ucsi module,
fwnode_usb_role_switch_get() will return -EPROBE_DEFER,
it is better to restart ucsi init work to find
it again every 100ms, total wait time is 10 second.

It also means change ucsi init work to delayed_work.

Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>
---
v2: keep original con->num in debug log
v3: change return value from -EAGAIN to PTR_ERR()
v4: change subject line,
    add counter for retry limit,
    correct commit descripton to match change in V3
v5: small update of commit description

 drivers/usb/typec/ucsi/ucsi.c | 32 ++++++++++++++++++++------------
 drivers/usb/typec/ucsi/ucsi.h |  6 +++++-
 2 files changed, 25 insertions(+), 13 deletions(-)

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index ce9192e..11f8808 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -1053,6 +1053,14 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
 	con->num = index + 1;
 	con->ucsi = ucsi;
 
+	cap->fwnode = ucsi_find_fwnode(con);
+	con->usb_role_sw = fwnode_usb_role_switch_get(cap->fwnode);
+	if (IS_ERR(con->usb_role_sw)) {
+		dev_err(ucsi->dev, "con%d: failed to get usb role switch\n",
+			con->num);
+		return PTR_ERR(con->usb_role_sw);
+	}
+
 	/* Delay other interactions with the con until registration is complete */
 	mutex_lock(&con->lock);
 
@@ -1088,7 +1096,6 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
 	if (con->cap.op_mode & UCSI_CONCAP_OPMODE_DEBUG_ACCESSORY)
 		*accessory = TYPEC_ACCESSORY_DEBUG;
 
-	cap->fwnode = ucsi_find_fwnode(con);
 	cap->driver_data = con;
 	cap->ops = &ucsi_ops;
 
@@ -1147,13 +1154,6 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
 		ucsi_port_psy_changed(con);
 	}
 
-	con->usb_role_sw = fwnode_usb_role_switch_get(cap->fwnode);
-	if (IS_ERR(con->usb_role_sw)) {
-		dev_err(ucsi->dev, "con%d: failed to get usb role switch\n",
-			con->num);
-		con->usb_role_sw = NULL;
-	}
-
 	/* Only notify USB controller if partner supports USB data */
 	if (!(UCSI_CONSTAT_PARTNER_FLAGS(con->status.flags) & UCSI_CONSTAT_PARTNER_FLAG_USB))
 		u_role = USB_ROLE_NONE;
@@ -1286,12 +1286,20 @@ static int ucsi_init(struct ucsi *ucsi)
 
 static void ucsi_init_work(struct work_struct *work)
 {
-	struct ucsi *ucsi = container_of(work, struct ucsi, work);
+	struct ucsi *ucsi = container_of(work, struct ucsi, work.work);
 	int ret;
 
 	ret = ucsi_init(ucsi);
 	if (ret)
 		dev_err(ucsi->dev, "PPM init failed (%d)\n", ret);
+
+	if (ret == -EPROBE_DEFER) {
+		if (ucsi->work_count++ > UCSI_ROLE_SWITCH_WAIT_COUNT)
+			return;
+
+		queue_delayed_work(system_long_wq, &ucsi->work,
+				   UCSI_ROLE_SWITCH_INTERVAL);
+	}
 }
 
 /**
@@ -1331,7 +1339,7 @@ struct ucsi *ucsi_create(struct device *dev, const struct ucsi_operations *ops)
 	if (!ucsi)
 		return ERR_PTR(-ENOMEM);
 
-	INIT_WORK(&ucsi->work, ucsi_init_work);
+	INIT_DELAYED_WORK(&ucsi->work, ucsi_init_work);
 	mutex_init(&ucsi->ppm_lock);
 	ucsi->dev = dev;
 	ucsi->ops = ops;
@@ -1366,7 +1374,7 @@ int ucsi_register(struct ucsi *ucsi)
 	if (!ucsi->version)
 		return -ENODEV;
 
-	queue_work(system_long_wq, &ucsi->work);
+	queue_delayed_work(system_long_wq, &ucsi->work, 0);
 
 	return 0;
 }
@@ -1383,7 +1391,7 @@ void ucsi_unregister(struct ucsi *ucsi)
 	u64 cmd = UCSI_SET_NOTIFICATION_ENABLE;
 
 	/* Make sure that we are not in the middle of driver initialization */
-	cancel_work_sync(&ucsi->work);
+	cancel_delayed_work_sync(&ucsi->work);
 
 	/* Disable notifications */
 	ucsi->ops->async_write(ucsi, UCSI_CONTROL, &cmd, sizeof(cmd));
diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h
index 280f1e1..8eb391e 100644
--- a/drivers/usb/typec/ucsi/ucsi.h
+++ b/drivers/usb/typec/ucsi/ucsi.h
@@ -287,7 +287,11 @@ struct ucsi {
 	struct ucsi_capability cap;
 	struct ucsi_connector *connector;
 
-	struct work_struct work;
+	struct delayed_work work;
+	int work_count;
+#define UCSI_ROLE_SWITCH_RETRY_PER_HZ	10
+#define UCSI_ROLE_SWITCH_INTERVAL	(HZ / UCSI_ROLE_SWITCH_RETRY_PER_HZ)
+#define UCSI_ROLE_SWITCH_WAIT_COUNT	(10 * UCSI_ROLE_SWITCH_RETRY_PER_HZ)
 
 	/* PPM Communication lock */
 	struct mutex ppm_lock;
-- 
2.7.4

Re: [PATCH v5 3/3] usb: typec: ucsi: Wait for the USB role switches

[Heikki Krogerus]

On Fri, Apr 22, 2022 at 11:10:22AM +0800, Linyu Yuan wrote:
> When role switch module probe late than ucsi module,
> fwnode_usb_role_switch_get() will return -EPROBE_DEFER,
> it is better to restart ucsi init work to find
> it again every 100ms, total wait time is 10 second.
> 
> It also means change ucsi init work to delayed_work.
> 
> Signed-off-by: Linyu Yuan <quic_linyyuan@quicinc.com>

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
> v2: keep original con->num in debug log
> v3: change return value from -EAGAIN to PTR_ERR()
> v4: change subject line,
>     add counter for retry limit,
>     correct commit descripton to match change in V3
> v5: small update of commit description
> 
>  drivers/usb/typec/ucsi/ucsi.c | 32 ++++++++++++++++++++------------
>  drivers/usb/typec/ucsi/ucsi.h |  6 +++++-
>  2 files changed, 25 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
> index ce9192e..11f8808 100644
> --- a/drivers/usb/typec/ucsi/ucsi.c
> +++ b/drivers/usb/typec/ucsi/ucsi.c
> @@ -1053,6 +1053,14 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
>  	con->num = index + 1;
>  	con->ucsi = ucsi;
>  
> +	cap->fwnode = ucsi_find_fwnode(con);
> +	con->usb_role_sw = fwnode_usb_role_switch_get(cap->fwnode);
> +	if (IS_ERR(con->usb_role_sw)) {
> +		dev_err(ucsi->dev, "con%d: failed to get usb role switch\n",
> +			con->num);
> +		return PTR_ERR(con->usb_role_sw);
> +	}
> +
>  	/* Delay other interactions with the con until registration is complete */
>  	mutex_lock(&con->lock);
>  
> @@ -1088,7 +1096,6 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
>  	if (con->cap.op_mode & UCSI_CONCAP_OPMODE_DEBUG_ACCESSORY)
>  		*accessory = TYPEC_ACCESSORY_DEBUG;
>  
> -	cap->fwnode = ucsi_find_fwnode(con);
>  	cap->driver_data = con;
>  	cap->ops = &ucsi_ops;
>  
> @@ -1147,13 +1154,6 @@ static int ucsi_register_port(struct ucsi *ucsi, int index)
>  		ucsi_port_psy_changed(con);
>  	}
>  
> -	con->usb_role_sw = fwnode_usb_role_switch_get(cap->fwnode);
> -	if (IS_ERR(con->usb_role_sw)) {
> -		dev_err(ucsi->dev, "con%d: failed to get usb role switch\n",
> -			con->num);
> -		con->usb_role_sw = NULL;
> -	}
> -
>  	/* Only notify USB controller if partner supports USB data */
>  	if (!(UCSI_CONSTAT_PARTNER_FLAGS(con->status.flags) & UCSI_CONSTAT_PARTNER_FLAG_USB))
>  		u_role = USB_ROLE_NONE;
> @@ -1286,12 +1286,20 @@ static int ucsi_init(struct ucsi *ucsi)
>  
>  static void ucsi_init_work(struct work_struct *work)
>  {
> -	struct ucsi *ucsi = container_of(work, struct ucsi, work);
> +	struct ucsi *ucsi = container_of(work, struct ucsi, work.work);
>  	int ret;
>  
>  	ret = ucsi_init(ucsi);
>  	if (ret)
>  		dev_err(ucsi->dev, "PPM init failed (%d)\n", ret);
> +
> +	if (ret == -EPROBE_DEFER) {
> +		if (ucsi->work_count++ > UCSI_ROLE_SWITCH_WAIT_COUNT)
> +			return;
> +
> +		queue_delayed_work(system_long_wq, &ucsi->work,
> +				   UCSI_ROLE_SWITCH_INTERVAL);
> +	}
>  }
>  
>  /**
> @@ -1331,7 +1339,7 @@ struct ucsi *ucsi_create(struct device *dev, const struct ucsi_operations *ops)
>  	if (!ucsi)
>  		return ERR_PTR(-ENOMEM);
>  
> -	INIT_WORK(&ucsi->work, ucsi_init_work);
> +	INIT_DELAYED_WORK(&ucsi->work, ucsi_init_work);
>  	mutex_init(&ucsi->ppm_lock);
>  	ucsi->dev = dev;
>  	ucsi->ops = ops;
> @@ -1366,7 +1374,7 @@ int ucsi_register(struct ucsi *ucsi)
>  	if (!ucsi->version)
>  		return -ENODEV;
>  
> -	queue_work(system_long_wq, &ucsi->work);
> +	queue_delayed_work(system_long_wq, &ucsi->work, 0);
>  
>  	return 0;
>  }
> @@ -1383,7 +1391,7 @@ void ucsi_unregister(struct ucsi *ucsi)
>  	u64 cmd = UCSI_SET_NOTIFICATION_ENABLE;
>  
>  	/* Make sure that we are not in the middle of driver initialization */
> -	cancel_work_sync(&ucsi->work);
> +	cancel_delayed_work_sync(&ucsi->work);
>  
>  	/* Disable notifications */
>  	ucsi->ops->async_write(ucsi, UCSI_CONTROL, &cmd, sizeof(cmd));
> diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h
> index 280f1e1..8eb391e 100644
> --- a/drivers/usb/typec/ucsi/ucsi.h
> +++ b/drivers/usb/typec/ucsi/ucsi.h
> @@ -287,7 +287,11 @@ struct ucsi {
>  	struct ucsi_capability cap;
>  	struct ucsi_connector *connector;
>  
> -	struct work_struct work;
> +	struct delayed_work work;
> +	int work_count;
> +#define UCSI_ROLE_SWITCH_RETRY_PER_HZ	10
> +#define UCSI_ROLE_SWITCH_INTERVAL	(HZ / UCSI_ROLE_SWITCH_RETRY_PER_HZ)
> +#define UCSI_ROLE_SWITCH_WAIT_COUNT	(10 * UCSI_ROLE_SWITCH_RETRY_PER_HZ)
>  
>  	/* PPM Communication lock */
>  	struct mutex ppm_lock;
> -- 
> 2.7.4

-- 
heikki