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-rw-r--r--drivers/input/touchscreen/goodix.c67
1 files changed, 44 insertions, 23 deletions
diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
index 32d2762..b3bbad7 100644
--- a/drivers/input/touchscreen/goodix.c
+++ b/drivers/input/touchscreen/goodix.c
@@ -72,6 +72,9 @@ struct goodix_ts_data {
#define GOODIX_REG_CONFIG_DATA 0x8047
#define GOODIX_REG_ID 0x8140
+#define GOODIX_BUFFER_STATUS_READY BIT(7)
+#define GOODIX_BUFFER_STATUS_TIMEOUT 20
+
#define RESOLUTION_LOC 1
#define MAX_CONTACTS_LOC 5
#define TRIGGER_LOC 6
@@ -195,35 +198,53 @@ static int goodix_get_cfg_len(u16 id)
static int goodix_ts_read_input_report(struct goodix_ts_data *ts, u8 *data)
{
+ unsigned long max_timeout;
int touch_num;
int error;
- error = goodix_i2c_read(ts->client, GOODIX_READ_COOR_ADDR, data,
- GOODIX_CONTACT_SIZE + 1);
- if (error) {
- dev_err(&ts->client->dev, "I2C transfer error: %d\n", error);
- return error;
- }
+ /*
+ * The 'buffer status' bit, which indicates that the data is valid, is
+ * not set as soon as the interrupt is raised, but slightly after.
+ * This takes around 10 ms to happen, so we poll for 20 ms.
+ */
+ max_timeout = jiffies + msecs_to_jiffies(GOODIX_BUFFER_STATUS_TIMEOUT);
+ do {
+ error = goodix_i2c_read(ts->client, GOODIX_READ_COOR_ADDR,
+ data, GOODIX_CONTACT_SIZE + 1);
+ if (error) {
+ dev_err(&ts->client->dev, "I2C transfer error: %d\n",
+ error);
+ return error;
+ }
- if (!(data[0] & 0x80))
- return -EAGAIN;
+ if (data[0] & GOODIX_BUFFER_STATUS_READY) {
+ touch_num = data[0] & 0x0f;
+ if (touch_num > ts->max_touch_num)
+ return -EPROTO;
+
+ if (touch_num > 1) {
+ data += 1 + GOODIX_CONTACT_SIZE;
+ error = goodix_i2c_read(ts->client,
+ GOODIX_READ_COOR_ADDR +
+ 1 + GOODIX_CONTACT_SIZE,
+ data,
+ GOODIX_CONTACT_SIZE *
+ (touch_num - 1));
+ if (error)
+ return error;
+ }
+
+ return touch_num;
+ }
- touch_num = data[0] & 0x0f;
- if (touch_num > ts->max_touch_num)
- return -EPROTO;
-
- if (touch_num > 1) {
- data += 1 + GOODIX_CONTACT_SIZE;
- error = goodix_i2c_read(ts->client,
- GOODIX_READ_COOR_ADDR +
- 1 + GOODIX_CONTACT_SIZE,
- data,
- GOODIX_CONTACT_SIZE * (touch_num - 1));
- if (error)
- return error;
- }
+ usleep_range(1000, 2000); /* Poll every 1 - 2 ms */
+ } while (time_before(jiffies, max_timeout));
- return touch_num;
+ /*
+ * The Goodix panel will send spurious interrupts after a
+ * 'finger up' event, which will always cause a timeout.
+ */
+ return 0;
}
static void goodix_ts_report_touch(struct goodix_ts_data *ts, u8 *coor_data)
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