Re: [PATCH] gpio: pca953x: Add optional reset gpio control

From: Steve Longerbeam
Date: Tue Jan 10 2017 - 14:11:59 EST




On 01/04/2017 02:31 AM, Andy Shevchenko wrote:

+ reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
+ GPIOD_OUT_LOW);
Shouldn't be _optional_exclusive?
See this recent discussion https://patchwork.ozlabs.org/patch/706002/
There is no devm_gpiod_get_optional_exclusive(), probably you confuse
the function with devm_reset_control_get_optional_exclusive().
Perhaps it's time to add
drivers/reset/reset-gpio.c ?

Yeah, looks like a GPIO based reset controller driver would need to be
implemented in order to go this route. The max7310 nodes in
imx6qdl-sabreauto.dtsi could then refer to that reset controller by the
'resets' phandle.

There are many many devices that would benefit from a GPIO reset
controller, I count 143 nodes under arch/arm/boot/dts that specify a
'reset-gpios' property.

But I don't have the time to write such a driver. So I would propose just
keeping the devm_gpiod_get_optional() call here. When such a gpio reset
controller is written, the work can begin to convert all the gpio reset users
to make use of it.

Steve