2023-01-09 07:32:32

by ChiYuan Huang

[permalink] [raw]
Subject: [PATCH RESEND v2] usb: typec: tcpm: Fix altmode re-registration causes sysfs create fail

From: ChiYuan Huang <[email protected]>

There's the altmode re-registeration issue after data role
swap (DR_SWAP).

Comparing to USBPD 2.0, in USBPD 3.0, it loose the limit that only DFP
can initiate the VDM command to get partner identity information.

For a USBPD 3.0 UFP device, it may already get the identity information
from its port partner before DR_SWAP. If DR_SWAP send or receive at the
mean time, 'send_discover' flag will be raised again. It causes discover
identify action restart while entering ready state. And after all
discover actions are done, the 'tcpm_register_altmodes' will be called.
If old altmode is not unregistered, this sysfs create fail can be found.

In 'DR_SWAP_CHANGE_DR' state case, only DFP will unregister altmodes.
For UFP, the original altmodes keep registered.

This patch fix the logic that after DR_SWAP, 'tcpm_unregister_altmodes'
must be called whatever the current data role is.

Reviewed-by: Macpaul Lin <[email protected]>
Fixes: ae8a2ca8a221 ("usb: typec: Group all TCPCI/TCPM code together)
Reported-by: TommyYl Chen <[email protected]>
Cc: [email protected]
Signed-off-by: ChiYuan Huang <[email protected]>
---
Since v2:
- Correct the mail sent from Richtek.
- Add 'Reviewed-by' tag.

Hi, Greg:

Please check this one. I have strongly requested our MIS to remove the confidential string.

ChiYuan Huang.
---
drivers/usb/typec/tcpm/tcpm.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index 904c7b4..59b366b 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -4594,14 +4594,13 @@ static void run_state_machine(struct tcpm_port *port)
tcpm_set_state(port, ready_state(port), 0);
break;
case DR_SWAP_CHANGE_DR:
- if (port->data_role == TYPEC_HOST) {
- tcpm_unregister_altmodes(port);
+ tcpm_unregister_altmodes(port);
+ if (port->data_role == TYPEC_HOST)
tcpm_set_roles(port, true, port->pwr_role,
TYPEC_DEVICE);
- } else {
+ else
tcpm_set_roles(port, true, port->pwr_role,
TYPEC_HOST);
- }
tcpm_ams_finish(port);
tcpm_set_state(port, ready_state(port), 0);
break;
--
2.7.4


2023-01-12 14:04:35

by Heikki Krogerus

[permalink] [raw]
Subject: Re: [PATCH RESEND v2] usb: typec: tcpm: Fix altmode re-registration causes sysfs create fail

On Mon, Jan 09, 2023 at 03:19:50PM +0800, [email protected] wrote:
> From: ChiYuan Huang <[email protected]>
>
> There's the altmode re-registeration issue after data role
> swap (DR_SWAP).
>
> Comparing to USBPD 2.0, in USBPD 3.0, it loose the limit that only DFP
> can initiate the VDM command to get partner identity information.
>
> For a USBPD 3.0 UFP device, it may already get the identity information
> from its port partner before DR_SWAP. If DR_SWAP send or receive at the
> mean time, 'send_discover' flag will be raised again. It causes discover
> identify action restart while entering ready state. And after all
> discover actions are done, the 'tcpm_register_altmodes' will be called.
> If old altmode is not unregistered, this sysfs create fail can be found.
>
> In 'DR_SWAP_CHANGE_DR' state case, only DFP will unregister altmodes.
> For UFP, the original altmodes keep registered.
>
> This patch fix the logic that after DR_SWAP, 'tcpm_unregister_altmodes'
> must be called whatever the current data role is.
>
> Reviewed-by: Macpaul Lin <[email protected]>
> Fixes: ae8a2ca8a221 ("usb: typec: Group all TCPCI/TCPM code together)
> Reported-by: TommyYl Chen <[email protected]>
> Cc: [email protected]
> Signed-off-by: ChiYuan Huang <[email protected]>

Acked-by: Heikki Krogerus <[email protected]>

> ---
> Since v2:
> - Correct the mail sent from Richtek.
> - Add 'Reviewed-by' tag.
>
> Hi, Greg:
>
> Please check this one. I have strongly requested our MIS to remove the confidential string.
>
> ChiYuan Huang.
> ---
> drivers/usb/typec/tcpm/tcpm.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 904c7b4..59b366b 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -4594,14 +4594,13 @@ static void run_state_machine(struct tcpm_port *port)
> tcpm_set_state(port, ready_state(port), 0);
> break;
> case DR_SWAP_CHANGE_DR:
> - if (port->data_role == TYPEC_HOST) {
> - tcpm_unregister_altmodes(port);
> + tcpm_unregister_altmodes(port);
> + if (port->data_role == TYPEC_HOST)
> tcpm_set_roles(port, true, port->pwr_role,
> TYPEC_DEVICE);
> - } else {
> + else
> tcpm_set_roles(port, true, port->pwr_role,
> TYPEC_HOST);
> - }
> tcpm_ams_finish(port);
> tcpm_set_state(port, ready_state(port), 0);
> break;
> --
> 2.7.4

--
heikki

2023-01-13 01:02:08

by ChiYuan Huang

[permalink] [raw]
Subject: Re: [PATCH RESEND v2] usb: typec: tcpm: Fix altmode re-registration causes sysfs create fail

On Mon, Jan 09, 2023 at 03:19:50PM +0800, [email protected] wrote:
> From: ChiYuan Huang <[email protected]>
>
> There's the altmode re-registeration issue after data role
> swap (DR_SWAP).
>
> Comparing to USBPD 2.0, in USBPD 3.0, it loose the limit that only DFP
> can initiate the VDM command to get partner identity information.
>
> For a USBPD 3.0 UFP device, it may already get the identity information
> from its port partner before DR_SWAP. If DR_SWAP send or receive at the
> mean time, 'send_discover' flag will be raised again. It causes discover
> identify action restart while entering ready state. And after all
> discover actions are done, the 'tcpm_register_altmodes' will be called.
> If old altmode is not unregistered, this sysfs create fail can be found.
>
> In 'DR_SWAP_CHANGE_DR' state case, only DFP will unregister altmodes.
> For UFP, the original altmodes keep registered.
>
> This patch fix the logic that after DR_SWAP, 'tcpm_unregister_altmodes'
> must be called whatever the current data role is.
>
> Reviewed-by: Macpaul Lin <[email protected]>
> Fixes: ae8a2ca8a221 ("usb: typec: Group all TCPCI/TCPM code together)
> Reported-by: TommyYl Chen <[email protected]>
> Cc: [email protected]
> Signed-off-by: ChiYuan Huang <[email protected]>
> ---
> Since v2:
> - Correct the mail sent from Richtek.
> - Add 'Reviewed-by' tag.
>

Sorry, it seems I focus on the email testing and forget to attach the issue
log in the v2 patch appendix.

If anyone check this issue. Please refer to the v1 patch link.
https://lore.kernel.org/lkml/[email protected]/
Inside this, the issue log show how it happened.

This can help better analyze this issue.

ChiYuan Huang.
> Hi, Greg:
>
> Please check this one. I have strongly requested our MIS to remove the confidential string.
>
> ChiYuan Huang.
> ---
> drivers/usb/typec/tcpm/tcpm.c | 7 +++----
> 1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
> index 904c7b4..59b366b 100644
> --- a/drivers/usb/typec/tcpm/tcpm.c
> +++ b/drivers/usb/typec/tcpm/tcpm.c
> @@ -4594,14 +4594,13 @@ static void run_state_machine(struct tcpm_port *port)
> tcpm_set_state(port, ready_state(port), 0);
> break;
> case DR_SWAP_CHANGE_DR:
> - if (port->data_role == TYPEC_HOST) {
> - tcpm_unregister_altmodes(port);
> + tcpm_unregister_altmodes(port);
> + if (port->data_role == TYPEC_HOST)
> tcpm_set_roles(port, true, port->pwr_role,
> TYPEC_DEVICE);
> - } else {
> + else
> tcpm_set_roles(port, true, port->pwr_role,
> TYPEC_HOST);
> - }
> tcpm_ams_finish(port);
> tcpm_set_state(port, ready_state(port), 0);
> break;
> --
> 2.7.4
>