Re: [PATCH] HID: i2c-hid: Disable runtime PM for LG touchscreen

From: Jiri Kosina
Date: Mon Nov 19 2018 - 10:28:30 EST


On Wed, 14 Nov 2018, Kai-Heng Feng wrote:

> LG touchscreen (1fd2:8001) stops working after reboot:
> [ 4.859153] i2c_hid i2c-SAPS2101:00: i2c_hid_get_input: incomplete report (64/66)
> [ 4.936070] i2c_hid i2c-SAPS2101:00: i2c_hid_get_input: incomplete report (64/66)
> [ 9.948224] i2c_hid i2c-SAPS2101:00: failed to reset device.
>
> The device in question stops working after receives SLEEP, ON, SLEEP
> commands in a short period. The scenario is like this:
> - Once the desktop session closes, it also closed the hid device, so the
> device gets runtime suspended and receives a SLEEP command.
> - Before calling shutdown callback, it gets runtime resumed and received
> an ON command.
> - In the shutdown callback, it receives another SLEEP command.
>
> I failed to find a reliable interval between ON/SLEEP commands that can
> make it work, so let's simply disable runtime PM for the device.
>
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> ---
> drivers/hid/hid-ids.h | 1 +
> drivers/hid/i2c-hid/i2c-hid-core.c | 2 ++
> 2 files changed, 3 insertions(+)
>
> diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
> index c0d668944dbe..bd636f529fad 100644
> --- a/drivers/hid/hid-ids.h
> +++ b/drivers/hid/hid-ids.h
> @@ -707,6 +707,7 @@
> #define USB_VENDOR_ID_LG 0x1fd2
> #define USB_DEVICE_ID_LG_MULTITOUCH 0x0064
> #define USB_DEVICE_ID_LG_MELFAS_MT 0x6007
> +#define I2C_DEVICE_ID_LG_8001 0x8001
>
> #define USB_VENDOR_ID_LOGITECH 0x046d
> #define USB_DEVICE_ID_LOGITECH_AUDIOHUB 0x0a0e
> diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
> index 3cde7c1b9c33..8555ce7e737b 100644
> --- a/drivers/hid/i2c-hid/i2c-hid-core.c
> +++ b/drivers/hid/i2c-hid/i2c-hid-core.c
> @@ -177,6 +177,8 @@ static const struct i2c_hid_quirks {
> I2C_HID_QUIRK_NO_RUNTIME_PM },
> { I2C_VENDOR_ID_RAYDIUM, I2C_PRODUCT_ID_RAYDIUM_4B33,
> I2C_HID_QUIRK_DELAY_AFTER_SLEEP },
> + { USB_VENDOR_ID_LG, I2C_DEVICE_ID_LG_8001,
> + I2C_HID_QUIRK_NO_RUNTIME_PM },
> { 0, 0 }
> };

Applied.

--
Jiri Kosina
SUSE Labs