diff --git a/drivers/input/touchscreen/st1232.c b/drivers/input/touchscreen/st1232.c index 459701056f2bda..b4e7bcbe9b91d9 100644 --- a/drivers/input/touchscreen/st1232.c +++ b/drivers/input/touchscreen/st1232.c @@ -26,6 +26,20 @@ #define ST1232_TS_NAME "st1232-ts" #define ST1633_TS_NAME "st1633-ts" +#define REG_STATUS 0x01 /* Device Status | Error Code */ + +#define STATUS_NORMAL 0x00 +#define STATUS_INIT 0x01 +#define STATUS_ERROR 0x02 +#define STATUS_AUTO_TUNING 0x03 +#define STATUS_IDLE 0x04 +#define STATUS_POWER_DOWN 0x05 + +#define ERROR_NONE 0x00 +#define ERROR_INVALID_ADDRESS 0x10 +#define ERROR_INVALID_VALUE 0x20 +#define ERROR_INVALID_PLATFORM 0x30 + #define REG_XY_RESOLUTION 0x04 #define REG_XY_COORDINATES 0x12 #define ST_TS_MAX_FINGERS 10 @@ -73,6 +87,22 @@ static int st1232_ts_read_data(struct st1232_ts_data *ts, u8 reg, return 0; } +static int st1232_ts_wait_ready(struct st1232_ts_data *ts) +{ + unsigned int retries; + int error; + + for (retries = 10; retries; retries--) { + error = st1232_ts_read_data(ts, REG_STATUS, 1); + if (!error && ts->read_buf[0] == (STATUS_NORMAL | ERROR_NONE)) + return 0; + + usleep_range(1000, 2000); + } + + return -ENXIO; +} + static int st1232_ts_read_resolution(struct st1232_ts_data *ts, u16 *max_x, u16 *max_y) { @@ -252,6 +282,11 @@ static int st1232_ts_probe(struct i2c_client *client, input_dev->name = "st1232-touchscreen"; input_dev->id.bustype = BUS_I2C; + /* Wait until device is ready */ + error = st1232_ts_wait_ready(ts); + if (error) + return error; + /* Read resolution from the chip */ error = st1232_ts_read_resolution(ts, &max_x, &max_y); if (error) {