Hi Andy, On 19-11-27 14:59, Andy Shevchenko wrote: > 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); > ... > } > > ? Thanks fpr your suggestion but we need to differentiate between reset and wake logic level. The wake-gpio keeps asserted while the reset is released. So the edt_ft5x06_ts_toggle_gpio() needs at least a 'is_reset' parameter but then the simplification is gone. Regards, Marco > -- > With Best Regards, > Andy Shevchenko > > > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
