Hi Kai-Heng,
On Mon, Jan 7, 2019 at 8:24 AM Kai-Heng Feng
<kai.heng.feng@xxxxxxxxxxxxx> wrote:
>
> While using Elan touchpads, the message floods:
> [ 136.138487] i2c_hid i2c-DELL08D6:00: i2c_hid_get_input: incomplete report (14/65535)
>
> Though the message flood is annoying, the device it self works without
> any issue. I suspect that the device in question takes too much time to
> pull the IRQ back to high after I2C host has done reading its data.
>
> Since the host receives all useful data, let's ignore the input report
> when there's no data.
>
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
Thanks for the v3.
This patch has just been brought to my attention, and I have one
question before applying it:
are those messages (without your patch) occurring all the time, or
just after resume?
I wonder if the pm_suspend delay we talked about in the other thread
would fix that issue in a cleaner way.
Cheers,
Benjamin
> ---
> v3:
> Fix compiler error/warnings.
>
> v2:
> Use dev_warn_once() to warn the user about the situation.
>
> drivers/hid/i2c-hid/i2c-hid-core.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
> index 8555ce7e737b..2f940c1de616 100644
> --- a/drivers/hid/i2c-hid/i2c-hid-core.c
> +++ b/drivers/hid/i2c-hid/i2c-hid-core.c
> @@ -50,6 +50,7 @@
> #define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET BIT(1)
> #define I2C_HID_QUIRK_NO_RUNTIME_PM BIT(2)
> #define I2C_HID_QUIRK_DELAY_AFTER_SLEEP BIT(3)
> +#define I2C_HID_QUIRK_BOGUS_IRQ BIT(4)
>
> /* flags */
> #define I2C_HID_STARTED 0
> @@ -179,6 +180,8 @@ static const struct i2c_hid_quirks {
> I2C_HID_QUIRK_DELAY_AFTER_SLEEP },
> { USB_VENDOR_ID_LG, I2C_DEVICE_ID_LG_8001,
> I2C_HID_QUIRK_NO_RUNTIME_PM },
> + { USB_VENDOR_ID_ELAN, HID_ANY_ID,
> + I2C_HID_QUIRK_BOGUS_IRQ },
> { 0, 0 }
> };
>
> @@ -503,6 +506,12 @@ static void i2c_hid_get_input(struct i2c_hid *ihid)
> return;
> }
>
> + if (ihid->quirks & I2C_HID_QUIRK_BOGUS_IRQ && ret_size == 0xffff) {
> + dev_warn_once(&ihid->client->dev, "%s: IRQ triggered but "
> + "there's no data\n", __func__);
> + return;
> + }
> +
> if ((ret_size > size) || (ret_size < 2)) {
> dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
> __func__, size, ret_size);
> --
> 2.17.1
>
