Messages in this thread | | | Date | Tue, 8 Nov 2016 16:12:48 +0200 | From | Mika Westerberg <> | Subject | Re: [PATCH] ACPI / gpio: avoid warning for gpio hogging code |
| |
On Tue, Nov 08, 2016 at 02:40:06PM +0100, Arnd Bergmann wrote: > The newly added acpi_gpiochip_scan_gpios function produces a few harmless > warnings: > > drivers/gpio/gpiolib-acpi.c: In function ‘acpi_gpiochip_add’: > drivers/gpio/gpiolib-acpi.c:925:7: error: ‘dflags’ may be used uninitialized in this function [-Werror=maybe-uninitialized] > drivers/gpio/gpiolib-acpi.c:925:9: error: ‘lflags’ may be used uninitialized in this function [-Werror=maybe-uninitialized] > > The problem is that he compiler cannot know that a negative return value > from fwnode_property_read_u32_array() or acpi_gpiochip_pin_to_gpio_offset() > implies that the IS_ERR(gpio_desc) is true, as the value could in theory > be below -MAX_ERRNO. > > The function already initializes its output values to zero, and moving > that intialization a little higher up ensures that we can never have > uninitialized data in the caller. > > Fixes: c80f1ba75df2 ("ACPI / gpio: Add hogging support") > Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
| |