Re: [PATCH] Input: atmel_mxt_ts - use mxt_acquire_irq in mxt_soft_reset

Dmitry Torokhov
2016-04-25T21:28:58Z

On Mon, Apr 11, 2016 at 10:31:45AM +0100, Nick Dyer wrote:
> If using IRQF_TRIGGER_FALLING, then there is a race here: if the reset
> completes before we enable the IRQ, then CHG is already low and touch
> will be broken.
>
> This has been seen on Chromebook Pixel 2.
>
> A workaround is to reconfig T18 COMMSCONFIG to enable the RETRIGEN bit
> using mxt-app:
> mxt-app -W -T18 44
> mxt-app --backup
>
> Tested-by: Tom Rini <trini@konsulko.com>
> Signed-off-by: Nick Dyer <nick.dyer@itdev.co.uk>

Applied, thank you.

> ---
> drivers/input/touchscreen/atmel_mxt_ts.c | 28 ++++++++++++++--------------
> 1 file changed, 14 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
> index 2160512..5af7907 100644
> --- a/drivers/input/touchscreen/atmel_mxt_ts.c
> +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
> @@ -1093,6 +1093,19 @@ static int mxt_t6_command(struct mxt_data *data, u16 cmd_offset,
> return 0;
> }
>
> +static int mxt_acquire_irq(struct mxt_data *data)
> +{
> + int error;
> +
> + enable_irq(data->irq);
> +
> + error = mxt_process_messages_until_invalid(data);
> + if (error)
> + return error;
> +
> + return 0;
> +}
> +
> static int mxt_soft_reset(struct mxt_data *data)
> {
> struct device *dev = &data->client->dev;
> @@ -1111,7 +1124,7 @@ static int mxt_soft_reset(struct mxt_data *data)
> /* Ignore CHG line for 100ms after reset */
> msleep(100);
>
> - enable_irq(data->irq);
> + mxt_acquire_irq(data);
>
> ret = mxt_wait_for_completion(data, &data->reset_completion,
> MXT_RESET_TIMEOUT);
> @@ -1466,19 +1479,6 @@ release_mem:
> return ret;
> }
>
> -static int mxt_acquire_irq(struct mxt_data *data)
> -{
> - int error;
> -
> - enable_irq(data->irq);
> -
> - error = mxt_process_messages_until_invalid(data);
> - if (error)
> - return error;
> -
> - return 0;
> -}
> -
> static int mxt_get_info(struct mxt_data *data)
> {
> struct i2c_client *client = data->client;
> --
> 2.5.0
>

--
Dmitry