linux-kernel - Re: [PATCH 01/14] Input: atmel_mxt_ts - do not pass suspend mode in platform data

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Date:   Wed, 14 Mar 2018 20:51:24 +0000
From:   Nick Dyer <nick@...anahar.org>
To:     Dmitry Torokhov <dmitry.torokhov@...il.com>
Cc:     linux-input@...r.kernel.org, Benson Leung <bleung@...omium.org>,
        Olof Johansson <olof@...om.net>, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 01/14] Input: atmel_mxt_ts - do not pass suspend mode in
 platform data

Hi Dmitry-

Thanks for sending these patches!

On Mon, Mar 12, 2018 at 12:08:54PM -0700, Dmitry Torokhov wrote:
> The way we are supposed to put controller to sleep and wake it up does not
> depend on the platform, but rather on controller itself. Controllers using
> T9 require manipulating T9 control register, while others, using newer
> T100, should be put to sleep by adjusting T7 power config.

I'm afraid this is actually a misconception. If you look at object table
for the older T9 device, you'll find it has the T7 object and it in fact
works exactly the same way as the T100-based device.

The MXT_SUSPEND_T9_CTRL is in there because on your older Pixel devices
the config saved into NVRAM on the touch controller has a zero byte in
the T9 CTRL setting, meaning the touch controller will never wake up
unless the driver knows to write 0x83 into it.

> We'll keep pdata->suspend_mode for now and remove it when we rework
> chromeos-laptop driver.
> 
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@...il.com>
> ---
>  drivers/input/touchscreen/atmel_mxt_ts.c | 15 ++++++---------
>  1 file changed, 6 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
> index 7659bc48f1db8..1aabfae1297ba 100644
> --- a/drivers/input/touchscreen/atmel_mxt_ts.c
> +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
> @@ -2868,8 +2868,8 @@ static const struct attribute_group mxt_attr_group = {
>  
>  static void mxt_start(struct mxt_data *data)
>  {
> -	switch (data->pdata->suspend_mode) {
> -	case MXT_SUSPEND_T9_CTRL:
> +	switch (data->multitouch) {
> +	case MXT_TOUCH_MULTI_T9:
>  		mxt_soft_reset(data);
>  
>  		/* Touch enable */
> @@ -2878,7 +2878,7 @@ static void mxt_start(struct mxt_data *data)
>  				MXT_TOUCH_MULTI_T9, MXT_T9_CTRL, 0x83);
>  		break;
>  
> -	case MXT_SUSPEND_DEEP_SLEEP:
> +	case MXT_TOUCH_MULTITOUCHSCREEN_T100:
>  	default:
>  		mxt_set_t7_power_cfg(data, MXT_POWER_CFG_RUN);
>  
> @@ -2886,19 +2886,18 @@ static void mxt_start(struct mxt_data *data)
>  		mxt_t6_command(data, MXT_COMMAND_CALIBRATE, 1, false);
>  		break;
>  	}
> -
>  }
>  
>  static void mxt_stop(struct mxt_data *data)
>  {
> -	switch (data->pdata->suspend_mode) {
> -	case MXT_SUSPEND_T9_CTRL:
> +	switch (data->multitouch) {
> +	case MXT_TOUCH_MULTI_T9:
>  		/* Touch disable */
>  		mxt_write_object(data,
>  				MXT_TOUCH_MULTI_T9, MXT_T9_CTRL, 0);
>  		break;
>  
> -	case MXT_SUSPEND_DEEP_SLEEP:
> +	case MXT_TOUCH_MULTITOUCHSCREEN_T100:
>  	default:
>  		mxt_set_t7_power_cfg(data, MXT_POWER_CFG_DEEPSLEEP);
>  		break;
> @@ -2954,8 +2953,6 @@ static const struct mxt_platform_data *mxt_parse_dt(struct i2c_client *client)
>  		pdata->t19_keymap = keymap;
>  	}
>  
> -	pdata->suspend_mode = MXT_SUSPEND_DEEP_SLEEP;
> -
>  	return pdata;
>  }
>  #else
> -- 
> 2.16.2.660.g709887971b-goog
>