| Message ID | 20230428194541.510674-1-andreas@kemnade.info |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] gpiolib: fix allocation of mixed dynamic/static GPIOs | expand |
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)) {
If static allocation and dynamic allocation GPIOs are present, dynamic allocation pollutes the numberspace for static allocation, causing static allocation to fail. Enfore 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 lets 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> --- Changes in V2: handle also the case of overlapping static allocation across DYNAMIC_BASE drivers/gpio/gpiolib.c | 2 ++ 1 file changed, 2 insertions(+)