| Message ID | 4E11825B.3000409@atmel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Jul 04, 2011 at 12:05:31PM +0300, Iiro Valkonen wrote: > The delay before the chip can be accessed after reset varies between different > chips in maXTouch family. Waiting for 200ms and then monitoring the CHG (chip > is ready when the line is low) is guaranteed to work with all chips. > > Signed-off-by: Iiro Valkonen <iiro.valkonen@atmel.com> > --- > drivers/input/touchscreen/atmel_mxt_ts.c | 4 +++- > include/linux/i2c/atmel_mxt_ts.h | 1 + > 2 files changed, 4 insertions(+), 1 deletions(-) > > diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c > index 1e61387..8870e7b 100644 > --- a/drivers/input/touchscreen/atmel_mxt_ts.c > +++ b/drivers/input/touchscreen/atmel_mxt_ts.c > @@ -170,7 +170,7 @@ > #define MXT_BOOT_VALUE 0xa5 > #define MXT_BACKUP_VALUE 0x55 > #define MXT_BACKUP_TIME 25 /* msec */ > -#define MXT_RESET_TIME 65 /* msec */ > +#define MXT_RESET_TIME 200 /* msec */ > > #define MXT_FWRESET_TIME 175 /* msec */ > > @@ -828,6 +828,8 @@ static int mxt_initialize(struct mxt_data *data) > mxt_write_object(data, MXT_GEN_COMMAND, > MXT_COMMAND_RESET, 1); > msleep(MXT_RESET_TIME); > + while (data->pdata->read_chg()) > + msleep(2); I would prefer if we did not wait indefinitely but timed out after certain number of retries. Thanks.
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c index 1e61387..8870e7b 100644 --- a/drivers/input/touchscreen/atmel_mxt_ts.c +++ b/drivers/input/touchscreen/atmel_mxt_ts.c @@ -170,7 +170,7 @@ #define MXT_BOOT_VALUE 0xa5 #define MXT_BACKUP_VALUE 0x55 #define MXT_BACKUP_TIME 25 /* msec */ -#define MXT_RESET_TIME 65 /* msec */ +#define MXT_RESET_TIME 200 /* msec */ #define MXT_FWRESET_TIME 175 /* msec */ @@ -828,6 +828,8 @@ static int mxt_initialize(struct mxt_data *data) mxt_write_object(data, MXT_GEN_COMMAND, MXT_COMMAND_RESET, 1); msleep(MXT_RESET_TIME); + while (data->pdata->read_chg()) + msleep(2); /* Update matrix size at info struct */ error = mxt_read_reg(client, MXT_MATRIX_X_SIZE, &val); diff --git a/include/linux/i2c/atmel_mxt_ts.h b/include/linux/i2c/atmel_mxt_ts.h index f027f7a..ef59c22 100644 --- a/include/linux/i2c/atmel_mxt_ts.h +++ b/include/linux/i2c/atmel_mxt_ts.h @@ -39,6 +39,7 @@ struct mxt_platform_data { unsigned int voltage; unsigned char orient; unsigned long irqflags; + u8(*read_chg) (void); }; #endif /* __LINUX_ATMEL_MXT_TS_H */
The delay before the chip can be accessed after reset varies between different chips in maXTouch family. Waiting for 200ms and then monitoring the CHG (chip is ready when the line is low) is guaranteed to work with all chips. Signed-off-by: Iiro Valkonen <iiro.valkonen@atmel.com> --- drivers/input/touchscreen/atmel_mxt_ts.c | 4 +++- include/linux/i2c/atmel_mxt_ts.h | 1 + 2 files changed, 4 insertions(+), 1 deletions(-)