The i2c-hid driver would quietly fail to probe the i2c-hid sensor-hub with an ACPI device-id of SMO91D0 every other boot. Specifically, the i2c_smbus_read_byte() "Make sure there is something at this address" check would fail every other boot. It seems that the BIOS does not properly reset/power-cycle the device leaving it in a confused state where it refuses to respond to i2c-xfers. On boots where probing the device failed, the driver-core puts the device in D3 after the probe-failure, which causes the probe to succeed the next boot. Putting the device in D3 from the shutdown-handler fixes the sensors not working every other boot. This has been tested on both a Lenovo Miix 2-10 and a Dell Venue 8 Pro 5830 both of which use an i2c-hid sensor-hub with an ACPI id of SMO91D0. Note that it is safe to call acpi_device_set_power() with a NULL pointer as first argument, so on none ACPI enumerated devices this change is a no-op. Cc: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> --- drivers/hid/i2c-hid/i2c-hid-core.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c index dbd04492825d..b303a1dd0e3f 100644 --- a/drivers/hid/i2c-hid/i2c-hid-core.c +++ b/drivers/hid/i2c-hid/i2c-hid-core.c @@ -935,6 +935,11 @@ static void i2c_hid_acpi_fix_up_power(struct device *dev) acpi_device_fix_up_power(adev); } +static void i2c_hid_acpi_shutdown(struct device *dev) +{ + acpi_device_set_power(ACPI_COMPANION(dev), ACPI_STATE_D3_COLD); +} + static const struct acpi_device_id i2c_hid_acpi_match[] = { {"ACPI0C50", 0 }, {"PNP0C50", 0 }, @@ -949,6 +954,7 @@ static inline int i2c_hid_acpi_pdata(struct i2c_client *client, } static inline void i2c_hid_acpi_fix_up_power(struct device *dev) {} +static inline void i2c_hid_acpi_shutdown(struct device *dev) {} #endif #ifdef CONFIG_OF @@ -1163,6 +1169,8 @@ static void i2c_hid_shutdown(struct i2c_client *client) i2c_hid_set_power(client, I2C_HID_PWR_SLEEP); free_irq(client->irq, ihid); + + i2c_hid_acpi_shutdown(&client->dev); } #ifdef CONFIG_PM_SLEEP -- 2.28.0