[PATCH 2/3] staging: most: hdm-usb: do h/w specific synchronization at configuration time

[Dan Carpenter]

On Tue, Oct 25, 2016 at 05:44:20PM +0200, Christian Gromm wrote:
> From: Andrey Shvetsov <andrey.shvetsov at k2l.de>
> 
> This patch puts the synchronization procedure trigger for asynchronous
> channels into the function hdm_configure_channel. Likewise, it removes
> triggering of hardware specific synchronization for other channel types
> from the probe function as it is not required.
> 
> Signed-off-by: Andrey Shvetsov <andrey.shvetsov at k2l.de>
> Signed-off-by: Christian Gromm <christian.gromm at microchip.com>
> ---
>  drivers/staging/most/hdm-usb/hdm_usb.c | 17 +++++++++--------
>  1 file changed, 9 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c
> index 1a630e1..db11930 100644
> --- a/drivers/staging/most/hdm-usb/hdm_usb.c
> +++ b/drivers/staging/most/hdm-usb/hdm_usb.c
> @@ -695,6 +695,15 @@ static int hdm_configure_channel(struct most_interface *iface, int channel,
>  			  - conf->buffer_size;
>  exit:
>  	mdev->conf[channel] = *conf;
> +	if (conf->data_type == MOST_CH_ASYNC) {
> +		u16 ep = mdev->ep_address[channel];
> +		int err = drci_wr_reg(mdev->usb_device,
> +				      DRCI_REG_BASE + DRCI_COMMAND + ep * 16,
> +				      1);
> +
> +		if (err < 0)
> +			dev_warn(dev, "sync for ep%02x failed", ep);
> +	}
>  	return 0;

This code is weird, because we goto exit without checking the
frame_size.  It looks like it doesn't matter much but it's sort of
puzzling what's going on.  There weren't any comments to explain it.

regards,
dan carpenter