[PATCH v4] usb: typec: tcpm: fix create duplicate source-capabilities file

[PATCH v4] usb: typec: tcpm: fix create duplicate source-capabilities file

[Xu Yang]

The kernel will dump in the below cases:
sysfs: cannot create duplicate filename
'/devices/virtual/usb_power_delivery/pd1/source-capabilities'

1. After soft reset has completed, an Explicit Contract negotiation occurs.
The sink device will receive source capabilitys again. This will cause
a duplicate source-capabilities file be created.
2. Power swap twice on a device that is initailly sink role.

This will unregister existing capabilities when above cases occurs.

Fixes: 8203d26905ee ("usb: typec: tcpm: Register USB Power Delivery Capabilities")
cc: <stable@vger.kernel.org>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

---
changelogs:
v2: unregister existing capabilities on specific cases
v3: add changelog and modify commit message
v4: reset port->partner_source_caps to NULL
---
 drivers/usb/typec/tcpm/tcpm.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index a0d943d78580..7f39cb9b3429 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4570,6 +4570,9 @@ static void run_state_machine(struct tcpm_port *port)
 	case SOFT_RESET:
 		port->message_id = 0;
 		port->rx_msgid = -1;
+		/* remove existing capabilities */
+		usb_power_delivery_unregister_capabilities(port->partner_source_caps);
+		port->partner_source_caps = NULL;
 		tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
 		tcpm_ams_finish(port);
 		if (port->pwr_role == TYPEC_SOURCE) {
@@ -4589,6 +4592,9 @@ static void run_state_machine(struct tcpm_port *port)
 	case SOFT_RESET_SEND:
 		port->message_id = 0;
 		port->rx_msgid = -1;
+		/* remove existing capabilities */
+		usb_power_delivery_unregister_capabilities(port->partner_source_caps);
+		port->partner_source_caps = NULL;
 		if (tcpm_pd_send_control(port, PD_CTRL_SOFT_RESET))
 			tcpm_set_state_cond(port, hard_reset_state(port), 0);
 		else
@@ -4718,6 +4724,9 @@ static void run_state_machine(struct tcpm_port *port)
 		tcpm_set_state(port, SNK_STARTUP, 0);
 		break;
 	case PR_SWAP_SNK_SRC_SINK_OFF:
+		/* will be source, remove existing capabilities */
+		usb_power_delivery_unregister_capabilities(port->partner_source_caps);
+		port->partner_source_caps = NULL;
 		/*
 		 * Prevent vbus discharge circuit from turning on during PR_SWAP
 		 * as this is not a disconnect.
-- 
2.34.1

Re: [PATCH v4] usb: typec: tcpm: fix create duplicate source-capabilities file

[Greg KH]

On Wed, Feb 15, 2023 at 01:49:51PM +0800, Xu Yang wrote:
> The kernel will dump in the below cases:
> sysfs: cannot create duplicate filename
> '/devices/virtual/usb_power_delivery/pd1/source-capabilities'
> 
> 1. After soft reset has completed, an Explicit Contract negotiation occurs.
> The sink device will receive source capabilitys again. This will cause
> a duplicate source-capabilities file be created.
> 2. Power swap twice on a device that is initailly sink role.
> 
> This will unregister existing capabilities when above cases occurs.
> 
> Fixes: 8203d26905ee ("usb: typec: tcpm: Register USB Power Delivery Capabilities")
> cc: <stable@vger.kernel.org>
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
> 
> ---
> changelogs:
> v2: unregister existing capabilities on specific cases
> v3: add changelog and modify commit message
> v4: reset port->partner_source_caps to NULL
> ---

Given the churn on this, and the seemingly lack-of-testing, I'll wait
until after -rc1 is out before applying this, is that ok?

thanks,

greg k-h

RE: [EXT] Re: [PATCH v4] usb: typec: tcpm: fix create duplicate source-capabilities file

[Xu Yang]

Hi Greg,

> -----Original Message-----
> From: Greg KH <gregkh@linuxfoundation.org>
> Sent: Wednesday, February 15, 2023 4:10 PM
> To: Xu Yang <xu.yang_2@nxp.com>
> Cc: linux@roeck-us.net; heikki.krogerus@linux.intel.com; linux-usb@vger.kernel.org; dl-linux-imx <linux-imx@nxp.com>;
> Jun Li <jun.li@nxp.com>
> Subject: [EXT] Re: [PATCH v4] usb: typec: tcpm: fix create duplicate source-capabilities file
> 
> Caution: EXT Email
> 
> On Wed, Feb 15, 2023 at 01:49:51PM +0800, Xu Yang wrote:
> > The kernel will dump in the below cases:
> > sysfs: cannot create duplicate filename
> > '/devices/virtual/usb_power_delivery/pd1/source-capabilities'
> >
> > 1. After soft reset has completed, an Explicit Contract negotiation occurs.
> > The sink device will receive source capabilitys again. This will cause
> > a duplicate source-capabilities file be created.
> > 2. Power swap twice on a device that is initailly sink role.
> >
> > This will unregister existing capabilities when above cases occurs.
> >
> > Fixes: 8203d26905ee ("usb: typec: tcpm: Register USB Power Delivery Capabilities")
> > cc: <stable@vger.kernel.org>
> > Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
> >
> > ---
> > changelogs:
> > v2: unregister existing capabilities on specific cases
> > v3: add changelog and modify commit message
> > v4: reset port->partner_source_caps to NULL
> > ---
> 
> Given the churn on this, and the seemingly lack-of-testing, I'll wait
> until after -rc1 is out before applying this, is that ok?

Sure. 
This patch works fine in my previous testing. But it failed at a specific
case today. I'll be carful in the future.

Thanks,
Xu Yang

> 
> thanks,
> 
> greg k-h

Re: [PATCH v4] usb: typec: tcpm: fix create duplicate source-capabilities file

[Guenter Roeck]

On 2/14/23 21:49, Xu Yang wrote:
> The kernel will dump in the below cases:
> sysfs: cannot create duplicate filename
> '/devices/virtual/usb_power_delivery/pd1/source-capabilities'
> 
> 1. After soft reset has completed, an Explicit Contract negotiation occurs.
> The sink device will receive source capabilitys again. This will cause
> a duplicate source-capabilities file be created.
> 2. Power swap twice on a device that is initailly sink role.
> 
> This will unregister existing capabilities when above cases occurs.
> 
> Fixes: 8203d26905ee ("usb: typec: tcpm: Register USB Power Delivery Capabilities")
> cc: <stable@vger.kernel.org>
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

Reviewed-by: Guenter Roeck <linux@roeck-us.net>

> 
> ---
> changelogs:
> v2: unregister existing capabilities on specific cases
> v3: add changelog and modify commit message
> v4: reset port->partner_source_caps to NULL
> ---
>   drivers/usb/typec/tcpm/tcpm.c | 9 +++++++++
>   1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index a0d943d78580..7f39cb9b3429 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -4570,6 +4570,9 @@ static void run_state_machine(struct tcpm_port *port)
>   	case SOFT_RESET:
>   		port->message_id = 0;
>   		port->rx_msgid = -1;
> +		/* remove existing capabilities */
> +		usb_power_delivery_unregister_capabilities(port->partner_source_caps);
> +		port->partner_source_caps = NULL;
>   		tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
>   		tcpm_ams_finish(port);
>   		if (port->pwr_role == TYPEC_SOURCE) {
> @@ -4589,6 +4592,9 @@ static void run_state_machine(struct tcpm_port *port)
>   	case SOFT_RESET_SEND:
>   		port->message_id = 0;
>   		port->rx_msgid = -1;
> +		/* remove existing capabilities */
> +		usb_power_delivery_unregister_capabilities(port->partner_source_caps);
> +		port->partner_source_caps = NULL;
>   		if (tcpm_pd_send_control(port, PD_CTRL_SOFT_RESET))
>   			tcpm_set_state_cond(port, hard_reset_state(port), 0);
>   		else
> @@ -4718,6 +4724,9 @@ static void run_state_machine(struct tcpm_port *port)
>   		tcpm_set_state(port, SNK_STARTUP, 0);
>   		break;
>   	case PR_SWAP_SNK_SRC_SINK_OFF:
> +		/* will be source, remove existing capabilities */
> +		usb_power_delivery_unregister_capabilities(port->partner_source_caps);
> +		port->partner_source_caps = NULL;
>   		/*
>   		 * Prevent vbus discharge circuit from turning on during PR_SWAP
>   		 * as this is not a disconnect.

Re: [PATCH v4] usb: typec: tcpm: fix create duplicate source-capabilities file

[Heikki Krogerus]

On Wed, Feb 15, 2023 at 01:49:51PM +0800, Xu Yang wrote:
> The kernel will dump in the below cases:
> sysfs: cannot create duplicate filename
> '/devices/virtual/usb_power_delivery/pd1/source-capabilities'
> 
> 1. After soft reset has completed, an Explicit Contract negotiation occurs.
> The sink device will receive source capabilitys again. This will cause
> a duplicate source-capabilities file be created.
> 2. Power swap twice on a device that is initailly sink role.
> 
> This will unregister existing capabilities when above cases occurs.
> 
> Fixes: 8203d26905ee ("usb: typec: tcpm: Register USB Power Delivery Capabilities")
> cc: <stable@vger.kernel.org>
> Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

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

> ---
> changelogs:
> v2: unregister existing capabilities on specific cases
> v3: add changelog and modify commit message
> v4: reset port->partner_source_caps to NULL
> ---
>  drivers/usb/typec/tcpm/tcpm.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index a0d943d78580..7f39cb9b3429 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -4570,6 +4570,9 @@ static void run_state_machine(struct tcpm_port *port)
>  	case SOFT_RESET:
>  		port->message_id = 0;
>  		port->rx_msgid = -1;
> +		/* remove existing capabilities */
> +		usb_power_delivery_unregister_capabilities(port->partner_source_caps);
> +		port->partner_source_caps = NULL;
>  		tcpm_pd_send_control(port, PD_CTRL_ACCEPT);
>  		tcpm_ams_finish(port);
>  		if (port->pwr_role == TYPEC_SOURCE) {
> @@ -4589,6 +4592,9 @@ static void run_state_machine(struct tcpm_port *port)
>  	case SOFT_RESET_SEND:
>  		port->message_id = 0;
>  		port->rx_msgid = -1;
> +		/* remove existing capabilities */
> +		usb_power_delivery_unregister_capabilities(port->partner_source_caps);
> +		port->partner_source_caps = NULL;
>  		if (tcpm_pd_send_control(port, PD_CTRL_SOFT_RESET))
>  			tcpm_set_state_cond(port, hard_reset_state(port), 0);
>  		else
> @@ -4718,6 +4724,9 @@ static void run_state_machine(struct tcpm_port *port)
>  		tcpm_set_state(port, SNK_STARTUP, 0);
>  		break;
>  	case PR_SWAP_SNK_SRC_SINK_OFF:
> +		/* will be source, remove existing capabilities */
> +		usb_power_delivery_unregister_capabilities(port->partner_source_caps);
> +		port->partner_source_caps = NULL;
>  		/*
>  		 * Prevent vbus discharge circuit from turning on during PR_SWAP
>  		 * as this is not a disconnect.
> -- 
> 2.34.1

-- 
heikki