Re: [PATCH] HID: cp2112: fix to force single data-report reply

[Ellen Wang <ellen@cumulusnetworks.com>]

Works as described.  Thank you!

By the way, I tested the code with and without your fix on my rev 2 
chip, and it behaved the same way as you describe on your rev 1 chip.

On 06/20/2015 11:20 PM, Antonio Borneo wrote:
> Current implementation of cp2112_raw_event() only accepts one data
> report at a time. If last received data report is not fully handled
> yet, a new incoming data report will overwrite it. In such case we
> don't guaranteed to propagate the correct incoming data.
>
> The trivial fix implemented here forces a single report at a time
> by requesting in cp2112_read() no more than 61 byte of data, which
> is the payload size of a single data report.
>
> Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
> ---
>
> Hi Jiri,
>
> I think this should go through linux-stable.
>
> Thanks,
> Antonio
>
>   drivers/hid/hid-cp2112.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c
> index 3318de6..a2dbbbe 100644
> --- a/drivers/hid/hid-cp2112.c
> +++ b/drivers/hid/hid-cp2112.c
> @@ -356,6 +356,8 @@ static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
>   	struct cp2112_force_read_report report;
>   	int ret;
>
> +	if (size > sizeof(dev->read_data))
> +		size = sizeof(dev->read_data);
>   	report.report = CP2112_DATA_READ_FORCE_SEND;
>   	report.length = cpu_to_be16(size);
>
>