diff options
Diffstat (limited to 'drivers/hid/i2c-hid/i2c-hid-core.c')
| -rw-r--r-- | drivers/hid/i2c-hid/i2c-hid-core.c | 20 |
1 files changed, 12 insertions, 8 deletions
diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c index 43664a24176f..4e87380d3edd 100644 --- a/drivers/hid/i2c-hid/i2c-hid-core.c +++ b/drivers/hid/i2c-hid/i2c-hid-core.c @@ -414,7 +414,19 @@ static int i2c_hid_set_power(struct i2c_hid *ihid, int power_state) i2c_hid_dbg(ihid, "%s\n", __func__); + /* + * Some STM-based devices need 400µs after a rising clock edge to wake + * from deep sleep, in which case the first request will fail due to + * the address not being acknowledged. Try after a short sleep to see + * if the device came alive on the bus. Certain Weida Tech devices also + * need this. + */ ret = i2c_hid_set_power_command(ihid, power_state); + if (ret && power_state == I2C_HID_PWR_ON) { + usleep_range(400, 500); + ret = i2c_hid_set_power_command(ihid, I2C_HID_PWR_ON); + } + if (ret) dev_err(&ihid->client->dev, "failed to change power setting.\n"); @@ -976,14 +988,6 @@ static int i2c_hid_core_resume(struct i2c_hid *ihid) enable_irq(client->irq); - /* Make sure the device is awake on the bus */ - ret = i2c_hid_probe_address(ihid); - if (ret < 0) { - dev_err(&client->dev, "nothing at address after resume: %d\n", - ret); - return -ENXIO; - } - /* On Goodix 27c6:0d42 wait extra time before device wakeup. * It's not clear why but if we send wakeup too early, the device will * never trigger input interrupts. |