On Sat, Sep 20, 2025 at 10:09:55PM +0200, Hans de Goede wrote:
When a software-node gets added to a device which already has another fwnode as primary node it will become the secondary fwnode for that device.
Currently if a software-node with GPIO properties ends up as the secondary fwnode then gpiod_find_by_fwnode() will fail to find the GPIOs.
Add a new gpiod_fwnode_lookup() helper which falls back to calling gpiod_find_by_fwnode() with the secondary fwnode if the GPIO was not found in the primary fwnode.
Fixes: e7f9ff5dc90c ("gpiolib: add support for software nodes") Cc: stable@vger.kernel.org Cc: Dmitry Torokhov dmitry.torokhov@gmail.com Signed-off-by: Hans de Goede hansg@kernel.org
Reviewed-by: Dmitry Torokhov dmitry.torokhov@gmail.com
Changes in v2:
- Add a new gpiod_fwnode_lookup() helper instead of putting the secondary fwnode check inside gpiod_find_by_fwnode()
drivers/gpio/gpiolib.c | 21 +++++++++++++++++++-- 1 file changed, 19 insertions(+), 2 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 0d2b470a252e..74d54513730a 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -4604,6 +4604,23 @@ static struct gpio_desc *gpiod_find_by_fwnode(struct fwnode_handle *fwnode, return desc; } +static struct gpio_desc *gpiod_fwnode_lookup(struct fwnode_handle *fwnode,
struct device *consumer,const char *con_id,unsigned int idx,enum gpiod_flags *flags,unsigned long *lookupflags)+{
- struct gpio_desc *desc;
- desc = gpiod_find_by_fwnode(fwnode, consumer, con_id, idx, flags, lookupflags);
- if (gpiod_not_found(desc) && !IS_ERR_OR_NULL(fwnode))
desc = gpiod_find_by_fwnode(fwnode->secondary, consumer, con_id,idx, flags, lookupflags);- return desc;
Bikeshedding for later. Maybe do it like this in case we can have more than 2 nodes at some point?
do { desc = gpiod_find_by_fwnode(fwnode, consumer, con_id, idx, flags, lookupflags); if (!gpiod_not_found(desc)) return desc;
fwnode = fwnode->secondary; } while (!IS_ERR_OR_NULL(fwnode));
return ERR_PTR(-ENOENT);
+}
struct gpio_desc *gpiod_find_and_request(struct device *consumer, struct fwnode_handle *fwnode, const char *con_id, @@ -4622,8 +4639,8 @@ struct gpio_desc *gpiod_find_and_request(struct device *consumer, int ret = 0; scoped_guard(srcu, &gpio_devices_srcu) {
desc = gpiod_find_by_fwnode(fwnode, consumer, con_id, idx,&flags, &lookupflags);
desc = gpiod_fwnode_lookup(fwnode, consumer, con_id, idx,&flags, &lookupflags);
Thanks.