Re: [PATCH] HID: i2c-hid: set power sleep before shutdown

Benjamin Tissoires
2016-06-20T09:35:39Z

On Jun 18 2016 or thereabouts, Guohua Zhong wrote:
> Add i2c_hid_shutdown for i2c-hid driver to send suspend cmd &
> disable irq before device shutdown.
>
> Some HW design is that the power to i2c hid device won't down
> after device shutdown. Also the i2c-hid driver do not send suspend
> cmd to the hid i2c device and disable its irq before shutdown.So
> if We touch the touchscreen or some other i2c hid device ,the power
> consumtion will be go up even when the device is in shutdown state.

Wow, that's a new one! Could you tell us which device board is behaving
that way (if not under NDA or such)?

>
> Though the root cause maybe a HW issue. But it seems that it is a
> good pratice to set power sleep for i2c-hid device before shutdown.

Works for me:
Acked-By: Benjamin Tissoires <benjamin.tissoires@redhat.com>

Cheers,
Benjamin

>
> Signed-off-by: Guohua Zhong <ghzhong@yifangdigital.com>
> ---
> drivers/hid/i2c-hid/i2c-hid.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
> index 2e021ba..d6ea97b 100644
> --- a/drivers/hid/i2c-hid/i2c-hid.c
> +++ b/drivers/hid/i2c-hid/i2c-hid.c
> @@ -1106,6 +1106,12 @@ static int i2c_hid_remove(struct i2c_client *client)
> return 0;
> }
>
> +static void i2c_hid_shutdown(struct i2c_client *client)
> +{
> + i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
> + disable_irq(client->irq);
> +}
> +
> #ifdef CONFIG_PM_SLEEP
> static int i2c_hid_suspend(struct device *dev)
> {
> @@ -1230,7 +1236,7 @@ static struct i2c_driver i2c_hid_driver = {
>
> .probe = i2c_hid_probe,
> .remove = i2c_hid_remove,
> -
> + .shutdown = i2c_hid_shutdown,
> .id_table = i2c_hid_id_table,
> };
>
> --
> 1.9.1
>
>