Patch "gpiolib: Handle no pin_ranges in gpiochip_generic_config()" has been added to the 6.7-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    gpiolib: Handle no pin_ranges in gpiochip_generic_config()

to the 6.7-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     gpiolib-handle-no-pin_ranges-in-gpiochip_generic_con.patch
and it can be found in the queue-6.7 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 1abd23fd10d91005cb6d5c950b0ec4b86d134330
Author: Emil Renner Berthing <emil.renner.berthing@xxxxxxxxxxxxx>
Date:   Mon Feb 19 18:25:13 2024 +0100

    gpiolib: Handle no pin_ranges in gpiochip_generic_config()
    
    [ Upstream commit ae366ba8576da0135d7d3db2dfa6304f3338d0c2 ]
    
    Similar to gpiochip_generic_request() and gpiochip_generic_free() the
    gpiochip_generic_config() function needs to handle the case where there
    are no pinctrl pins mapped to the GPIOs, usually through the gpio-ranges
    device tree property.
    
    Commit f34fd6ee1be8 ("gpio: dwapb: Use generic request, free and
    set_config") set the .set_config callback to gpiochip_generic_config()
    in the dwapb GPIO driver so the GPIO API can set pinctrl configuration
    for the corresponding pins. Most boards using the dwapb driver do not
    set the gpio-ranges device tree property though, and in this case
    gpiochip_generic_config() would return -EPROPE_DEFER rather than the
    previous -ENOTSUPP return value. This in turn makes
    gpio_set_config_with_argument_optional() fail and propagate the error to
    any driver requesting GPIOs.
    
    Fixes: 2956b5d94a76 ("pinctrl / gpio: Introduce .set_config() callback for GPIO chips")
    Reported-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
    Closes: https://lore.kernel.org/linux-gpio/ZdC_g3U4l0CJIWzh@xhacker/
    Tested-by: Jisheng Zhang <jszhang@xxxxxxxxxx>
    Signed-off-by: Emil Renner Berthing <emil.renner.berthing@xxxxxxxxxxxxx>
    Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
    Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 95d2a7b2ea3e2..15de124d5b402 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -2043,6 +2043,11 @@ EXPORT_SYMBOL_GPL(gpiochip_generic_free);
 int gpiochip_generic_config(struct gpio_chip *gc, unsigned int offset,
 			    unsigned long config)
 {
+#ifdef CONFIG_PINCTRL
+	if (list_empty(&gc->gpiodev->pin_ranges))
+		return -ENOTSUPP;
+#endif
+
 	return pinctrl_gpio_set_config(gc, offset, config);
 }
 EXPORT_SYMBOL_GPL(gpiochip_generic_config);