From: Andreas Kemnade andreas@kemnade.info
[ Upstream commit 7dd3d9bd873f138675cb727eaa51a498d99f0e89 ]
If static allocation and dynamic allocation GPIOs are present, dynamic allocation pollutes the numberspace for static allocation, causing static allocation to fail. Enforce dynamic allocation above GPIO_DYNAMIC_BASE.
Seen on a GTA04 when omap-gpio (static) and twl-gpio (dynamic) raced: [some successful registrations of omap_gpio instances] [ 2.553833] twl4030_gpio twl4030-gpio: gpio (irq 145) chaining IRQs 161..178 [ 2.561401] gpiochip_find_base: found new base at 160 [ 2.564392] gpio gpiochip5: (twl4030): added GPIO chardev (254:5) [ 2.564544] gpio gpiochip5: registered GPIOs 160 to 177 on twl4030 [...] [ 2.692169] omap-gpmc 6e000000.gpmc: GPMC revision 5.0 [ 2.697357] gpmc_mem_init: disabling cs 0 mapped at 0x0-0x1000000 [ 2.703643] gpiochip_find_base: found new base at 178 [ 2.704376] gpio gpiochip6: (omap-gpmc): added GPIO chardev (254:6) [ 2.704589] gpio gpiochip6: registered GPIOs 178 to 181 on omap-gpmc [...] [ 2.840393] gpio gpiochip7: Static allocation of GPIO base is deprecated, use dynamic allocation. [ 2.849365] gpio gpiochip7: (gpio-160-191): GPIO integer space overlap, cannot add chip [ 2.857513] gpiochip_add_data_with_key: GPIOs 160..191 (gpio-160-191) failed to register, -16 [ 2.866149] omap_gpio 48310000.gpio: error -EBUSY: Could not register gpio chip
On that device it is fixed invasively by commit 92bf78b33b0b4 ("gpio: omap: use dynamic allocation of base") but let's also fix that for devices where there is still a mixture of static and dynamic allocation.
Fixes: 7b61212f2a07 ("gpiolib: Get rid of ARCH_NR_GPIOS") Signed-off-by: Andreas Kemnade andreas@kemnade.info Reviewed-by: christophe.leroy@csgroup.eu Reviewed-by: Andy Shevchenko andy.shevchenko@gmail.com Reviewed-by: Linus Walleij linus.walleij@linaro.org Signed-off-by: Bartosz Golaszewski bartosz.golaszewski@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpio/gpiolib.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 19bd23044b017..4472214fcd43a 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -193,6 +193,8 @@ static int gpiochip_find_base(int ngpio) break; /* nope, check the space right after the chip */ base = gdev->base + gdev->ngpio; + if (base < GPIO_DYNAMIC_BASE) + base = GPIO_DYNAMIC_BASE; }
if (gpio_is_valid(base)) {