On 07/14, Timur Tabi wrote:

On 07/14/2017 12:11 PM, Stephen Boyd wrote:

quoted

gpiochips also have a request() hook. Can we use that before
initializing direction to make sure the GPIO is accessible?

So I tried it, and it didn't work:

static int msm_gpio_request(struct gpio_chip *chip, unsigned int offset)
{
	pr_info("%s:%u offset=%u\n", __func__, __LINE__, offset);

	return 0;
}

static struct gpio_chip msm_gpio_template = {
	.request          = msm_gpio_request,
	...

msm_gpio_request() is never called when the driver loads.  In fact,
I can't figure out when it would be called.

Right, the gpiolib core would need to be updated to request the
gpio in gpiochip_add_data() around the loop where it goes and
configures things. And it could ignore ones that it can't request
there.

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