[PATCH v2] usb: typec: tcpm: Return ENOTSUPP for power supply prop writes

[PATCH v2] usb: typec: tcpm: Return ENOTSUPP for power supply prop writes

[Badhri Jagan Sridharan]

When the port does not support USB PD, prevent transition to PD
only states when power supply property is written. In this case,
TCPM transitions to SNK_NEGOTIATE_CAPABILITIES
which should not be the case given that the port is not pd_capable.

[   84.308251] state change SNK_READY -> SNK_NEGOTIATE_CAPABILITIES [rev3 NONE_AMS]
[   84.308335] Setting usb_comm capable false
[   84.323367] set_auto_vbus_discharge_threshold mode:3 pps_active:n vbus:5000 ret:0
[   84.323376] state change SNK_NEGOTIATE_CAPABILITIES -> SNK_WAIT_CAPABILITIES [rev3 NONE_AMS]

Fixes: e9e6e164ed8f6 ("usb: typec: tcpm: Support non-PD mode")
Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
---
Changes since v1:
- Add Fixes tag.
---
 drivers/usb/typec/tcpm/tcpm.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index ea5a917c51b1..904c7b4ce2f0 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -6320,6 +6320,13 @@ static int tcpm_psy_set_prop(struct power_supply *psy,
 	struct tcpm_port *port = power_supply_get_drvdata(psy);
 	int ret;
 
+	/*
+	 * All the properties below are related to USB PD. The check needs to be
+	 * property specific when a non-pd related property is added.
+	 */
+	if (!port->pd_supported)
+		return -EOPNOTSUPP;
+
 	switch (psp) {
 	case POWER_SUPPLY_PROP_ONLINE:
 		ret = tcpm_psy_set_online(port, val);
-- 
2.37.1.595.g718a3a8f04-goog

Re: [PATCH v2] usb: typec: tcpm: Return ENOTSUPP for power supply prop writes

[kernel test robot]

Hi,

Thanks for your patch.

FYI: kernel test robot notices the stable kernel rule is not satisfied.

Rule: 'Cc: stable@vger.kernel.org' or 'commit <sha1> upstream.'
Subject: [PATCH v2] usb: typec: tcpm: Return ENOTSUPP for power supply prop writes
Link: https://lore.kernel.org/stable/20220816191150.1432166-1-badhri%40google.com

The check is based on https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

Re: [PATCH v2] usb: typec: tcpm: Return ENOTSUPP for power supply prop writes

[Greg Kroah-Hartman]

On Tue, Aug 16, 2022 at 12:11:50PM -0700, Badhri Jagan Sridharan wrote:
> When the port does not support USB PD, prevent transition to PD
> only states when power supply property is written. In this case,
> TCPM transitions to SNK_NEGOTIATE_CAPABILITIES
> which should not be the case given that the port is not pd_capable.
> 
> [   84.308251] state change SNK_READY -> SNK_NEGOTIATE_CAPABILITIES [rev3 NONE_AMS]
> [   84.308335] Setting usb_comm capable false
> [   84.323367] set_auto_vbus_discharge_threshold mode:3 pps_active:n vbus:5000 ret:0
> [   84.323376] state change SNK_NEGOTIATE_CAPABILITIES -> SNK_WAIT_CAPABILITIES [rev3 NONE_AMS]
> 
> Fixes: e9e6e164ed8f6 ("usb: typec: tcpm: Support non-PD mode")
> Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
> ---
> Changes since v1:
> - Add Fixes tag.
> ---
>  drivers/usb/typec/tcpm/tcpm.c | 7 +++++++
>  1 file changed, 7 insertions(+)


<formletter>

This is not the correct way to submit patches for inclusion in the
stable kernel tree.  Please read:
    https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html
for how to do this properly.

</formletter>