On Wed, May 4, 2016 at 10:21 AM, Geert Uytterhoeven <geert+renesas@xxxxxxxxx> wrote: > Currrently the gpio_chip.to_irq() callback returns -ENOSYS on error, > which causes bad interactions with the serial_mctrl_gpio helpers. > > mctrl_gpio_init() returns -ENOSYS if GPIOLIB is not enabled, which is > intended to be ignored by its callers. However, ignoring -ENOSYS when it > was caused by a gpiod_to_irq() failure will lead to a crash later: > > Unable to handle kernel paging request at virtual address ffffffde > ... > PC is at mctrl_gpio_set+0x14/0x78 > > Fix this by returning zero instead, like gpiochip_to_irq() does. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> > --- > This depends on "gpio: make gpiod_to_irq() return negative for NO_IRQ" > for proper handling by callers of mctrl_gpio_init(). > Hence I think it's best to take this through the GPIO tree, after the > above has been applied. > > v2: > - Return zero instead of -ENXIO. Patch applied. Yours, Linus Walleij
