2011/8/22 Linus Walleij linus.walleij@linaro.org:
On Sun, Aug 21, 2011 at 4:42 PM, Barry Song 21cnbao@gmail.com wrote:
it seems there is not an actual example that gpio requests pin from pinctrl yet. i might give one on SiRFprimaII.
No good example yet, no.
The reason is that for the U300 that I use as guinea pig, the GPIO driver is tangled up in discussions about how to handle the special control mechanics like requesting muxing and biasing pins. Right now it seems easier to rewrite all that to use the new pinctrl subsystem rather than actually trying to work it into the GPIO subsystem first and refactor from there, and that needs quite a bit of upfront work...
Do you want the pinmux_request_gpio called by the gpiolib driver or by every device driver who uses this gpio? Do you think the following make sense in gpiolib driver? static int xxx_gpio_request(struct gpio_chip *chip, unsigned offset) { int ret = 0;
ret = pinmux_request_gpio(chip->base + offset); if (ret) goto out; ..... out: return ret; }
Linus Walleij
Thanks Barry