Some devices use combo PHYs (i.e. USB3 + DisplayPort), which also
handle the orientation mux. These PHYs are referenced twice from
the USB-C connector (USB super-speed lines and SBU/AUX lines)
resulting in the switch being configured twice. Avoid this by
dropping duplicates.
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
---
drivers/usb/typec/mux.c | 14 +++++++++++++-
1 file changed, 13 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/typec/mux.c b/drivers/usb/typec/mux.c
index 182c902c42f6..db35b7398343 100644
--- a/drivers/usb/typec/mux.c
+++ b/drivers/usb/typec/mux.c
@@ -72,9 +72,9 @@ struct typec_switch *fwnode_typec_switch_get(struct fwnode_handle *fwnode)
{
struct typec_switch_dev *sw_devs[TYPEC_MUX_MAX_DEVS];
struct typec_switch *sw;
+ int i, j, k;
int count;
int err;
- int i;
sw = kzalloc(sizeof(*sw), GFP_KERNEL);
if (!sw)
@@ -96,6 +96,18 @@ struct typec_switch *fwnode_typec_switch_get(struct fwnode_handle *fwnode)
}
}
+ /* eliminate duplicates */
+ for (i = 0; i < count; i++) {
+ for (j = i + 1; j < count; j++) {
+ if (sw_devs[j] == sw_devs[i]) {
+ put_device(&sw_devs[j]->dev);
+ for (k = j; k < count; k++)
+ sw_devs[k] = sw_devs[k+1];
+ count--;
+ }
+ }
+ }
+
for (i = 0; i < count; i++) {
WARN_ON(!try_module_get(sw_devs[i]->dev.parent->driver->owner));
sw->sw_devs[i] = sw_devs[i];
--
2.51.0
Hi Sebastian,
Fri, Feb 13, 2026 at 08:23:28PM +0100, Sebastian Reichel wrote:
> Some devices use combo PHYs (i.e. USB3 + DisplayPort), which also
> handle the orientation mux. These PHYs are referenced twice from
> the USB-C connector (USB super-speed lines and SBU/AUX lines)
> resulting in the switch being configured twice. Avoid this by
> dropping duplicates.
>
> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
> ---
> drivers/usb/typec/mux.c | 14 +++++++++++++-
> 1 file changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/typec/mux.c b/drivers/usb/typec/mux.c
> index 182c902c42f6..db35b7398343 100644
> --- a/drivers/usb/typec/mux.c
> +++ b/drivers/usb/typec/mux.c
> @@ -72,9 +72,9 @@ struct typec_switch *fwnode_typec_switch_get(struct fwnode_handle *fwnode)
> {
> struct typec_switch_dev *sw_devs[TYPEC_MUX_MAX_DEVS];
> struct typec_switch *sw;
> + int i, j, k;
> int count;
> int err;
> - int i;
>
> sw = kzalloc(sizeof(*sw), GFP_KERNEL);
> if (!sw)
> @@ -96,6 +96,18 @@ struct typec_switch *fwnode_typec_switch_get(struct fwnode_handle *fwnode)
> }
> }
>
> + /* eliminate duplicates */
> + for (i = 0; i < count; i++) {
> + for (j = i + 1; j < count; j++) {
> + if (sw_devs[j] == sw_devs[i]) {
> + put_device(&sw_devs[j]->dev);
> + for (k = j; k < count; k++)
> + sw_devs[k] = sw_devs[k+1];
> + count--;
> + }
> + }
> + }
I think that check could be done in typec_switch_match(). Just pass
that sw_devs to it as "data":
- count = fwnode_connection_find_matches(fwnode, "orientation-switch", NULL,
+ count = fwnode_connection_find_matches(fwnode, "orientation-switch", sw_devs,
And then in typec_switch_match(), probable as the second last step:
static void *typec_switch_match(const struct fwnode_handle *fwnode,
const char *id, void *data)
{
+ struct typec_switch_dev *sw_devs = data;
+ int i;
...
dev = class_find_device(&typec_mux_class, NULL, fwnode,
switch_fwnode_match);
+ /* Skip duplicates */
+ for (i = 0; i < TYPEC_MUX_MAX_DEVS; i++)
+ if (to_typec_switch_dev(dev) == sw_devs[i]) {
+ put_device(dev);
+ return NULL;
+ }
return dev ? to_typec_switch_dev(dev) : ERR_PTR(-EPROBE_DEFER);
}
thanks,
--
heikki
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