usb: typec: tcpm: unregister existing source caps before re-registration

Check and unregister existing source caps in tcpm_register_source_caps
function before registering new ones. This change fixes following
warning when port partner resends source caps after negotiating PD contract
for the purpose of re-negotiation.

[  343.135030][  T151] sysfs: cannot create duplicate filename '/devices/virtual/usb_power_delivery/pd1/source-capabilities'
[  343.135071][  T151] Call trace:
[  343.135076][  T151]  dump_backtrace+0xe8/0x108
[  343.135099][  T151]  show_stack+0x18/0x24
[  343.135106][  T151]  dump_stack_lvl+0x50/0x6c
[  343.135119][  T151]  dump_stack+0x18/0x24
[  343.135126][  T151]  sysfs_create_dir_ns+0xe0/0x140
[  343.135137][  T151]  kobject_add_internal+0x228/0x424
[  343.135146][  T151]  kobject_add+0x94/0x10c
[  343.135152][  T151]  device_add+0x1b0/0x4c0
[  343.135187][  T151]  device_register+0x20/0x34
[  343.135195][  T151]  usb_power_delivery_register_capabilities+0x90/0x20c
[  343.135209][  T151]  tcpm_pd_rx_handler+0x9f0/0x15b8
[  343.135216][  T151]  kthread_worker_fn+0x11c/0x260
[  343.135227][  T151]  kthread+0x114/0x1bc
[  343.135235][  T151]  ret_from_fork+0x10/0x20
[  343.135265][  T151] kobject: kobject_add_internal failed for source-capabilities with -EEXIST, don't try to register things with the same name in the same directory.

Fixes: 8203d26 ("usb: typec: tcpm: Register USB Power Delivery Capabilities")
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: Mark Brown <[email protected]>
Signed-off-by: Amit Sunil Dhamne <[email protected]>
Reviewed-by: Heikki Krogerus <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: amitsd2

drivers/usb/typec/tcpm/tcpm.c

@@ -2996,7 +2996,7 @@ static int tcpm_register_source_caps(struct tcpm_port *port)
 {
 	struct usb_power_delivery_desc desc = { port->negotiated_rev };
 	struct usb_power_delivery_capabilities_desc caps = { };
-	struct usb_power_delivery_capabilities *cap;
+	struct usb_power_delivery_capabilities *cap = port->partner_source_caps;
 
 	if (!port->partner_pd)
 		port->partner_pd = usb_power_delivery_register(NULL, &desc);
@@ -3006,6 +3006,9 @@ static int tcpm_register_source_caps(struct tcpm_port *port)
 	memcpy(caps.pdo, port->source_caps, sizeof(u32) * port->nr_source_caps);
 	caps.role = TYPEC_SOURCE;
 
+	if (cap)
+		usb_power_delivery_unregister_capabilities(cap);
+
 	cap = usb_power_delivery_register_capabilities(port->partner_pd, &caps);
 	if (IS_ERR(cap))
 		return PTR_ERR(cap);