Re: [PATCH v2 5/5] Input: edt-ft5x06 - improve power management operations

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On Wed, Nov 27, 2019 at 01:09:48PM +0100, Marco Felsch wrote:
> It is possible to bring the device into a deep sleep state. To exit this
> state the reset or wakeup pin must be toggeled as documented in [1].
> Because of the poor documentation I used the several downstream kernels
> [2] and other applications notes [3] to indentify the related registers.
> 
> Furthermore I added the support to disable the device completely. This is
> the most effective power-saving mechanism. Disabling the device don't
> change the suspend logic because the hibernate mode needs a hardware
> reset anyway.
> 
> [1] https://www.newhavendisplay.com/appnotes/datasheets/touchpanel/FT5x26.pdf
> [2] https://github.com/linux-sunxi/linux-sunxi/blob/sunxi-3.4/drivers/input/touchscreen/ft5x_ts.c
>     https://github.com/Pablito2020/focaltech-touch-driver/blob/master/ft5336_driver.c
> [3] https://www.newhavendisplay.com/appnotes/datasheets/touchpanel/FT5x16_registers.pdf


> +	/* Recover from hibernate mode if hardware supports it */
> +	if (tsdata->wake_gpio) {
> +		gpiod_set_value_cansleep(tsdata->wake_gpio, 0);
> +		usleep_range(5000, 6000);
> +		gpiod_set_value_cansleep(tsdata->wake_gpio, 1);
> +		msleep(300);
> +	} else if (tsdata->reset_gpio) {
> +		gpiod_set_value_cansleep(tsdata->reset_gpio, 1);
> +		usleep_range(5000, 6000);
> +		gpiod_set_value_cansleep(tsdata->reset_gpio, 0);
> +		msleep(300);
> +	}

Perhaps

static void edt_ft5x06_ts_toggle_gpio(struct gpio_desc *gpiod)
{
	...
}

...resume(...)
{
	...
	if (wake_gpio)
		...toggle_gpio(wake_gpio);
	else if (reset_gpio)
		...toggle_gpio(reset_gpio);
	...
}

?

-- 
With Best Regards,
Andy Shevchenko





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