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Diffstat (limited to 'drivers/hid/i2c-hid/i2c-hid-core.c')
-rw-r--r--drivers/hid/i2c-hid/i2c-hid-core.c22
1 files changed, 13 insertions, 9 deletions
diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
index 294c84e136d7..dbd04492825d 100644
--- a/drivers/hid/i2c-hid/i2c-hid-core.c
+++ b/drivers/hid/i2c-hid/i2c-hid-core.c
@@ -420,6 +420,19 @@ static int i2c_hid_set_power(struct i2c_client *client, int power_state)
dev_err(&client->dev, "failed to change power setting.\n");
set_pwr_exit:
+
+ /*
+ * The HID over I2C specification states that if a DEVICE needs time
+ * after the PWR_ON request, it should utilise CLOCK stretching.
+ * However, it has been observered that the Windows driver provides a
+ * 1ms sleep between the PWR_ON and RESET requests.
+ * According to Goodix Windows even waits 60 ms after (other?)
+ * PWR_ON requests. Testing has confirmed that several devices
+ * will not work properly without a delay after a PWR_ON request.
+ */
+ if (!ret && power_state == I2C_HID_PWR_ON)
+ msleep(60);
+
return ret;
}
@@ -441,15 +454,6 @@ static int i2c_hid_hwreset(struct i2c_client *client)
if (ret)
goto out_unlock;
- /*
- * The HID over I2C specification states that if a DEVICE needs time
- * after the PWR_ON request, it should utilise CLOCK stretching.
- * However, it has been observered that the Windows driver provides a
- * 1ms sleep between the PWR_ON and RESET requests and that some devices
- * rely on this.
- */
- usleep_range(1000, 5000);
-
i2c_hid_dbg(ihid, "resetting...\n");
ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0);