diff options
| author | Andrey Shvetsov <andrey.shvetsov@k2l.de> | 2017-04-07 15:38:38 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-04-08 12:41:40 +0200 |
| commit | f500192890c7c6745a92b677f5f69e58a2d60715 (patch) | |
| tree | cf91d9afdafdea53a895102ef9b6726e132862f4 /drivers/staging/most/hdm-usb/hdm_usb.c | |
| parent | 2c4aaa1fffe8d01c621e2515cd5f290227949e71 (diff) | |
staging: most: usb: fix calculation of the extra_len
The final size of the buffer used for the streaming transfer consists of
the size for the user payload (buffer_size) and the size for the gaps
needed by the controller (extra_len).
The current implementation of the hdm_configure_channel() corrects the
buffer size down to the next appropriate for the hardware value, that is
the whole number of frames, but uses the old unaligned value to
calculate the extra_len.
Current patch fixes the described problem.
Signed-off-by: Andrey Shvetsov <andrey.shvetsov@k2l.de>
Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/most/hdm-usb/hdm_usb.c')
| -rw-r--r-- | drivers/staging/most/hdm-usb/hdm_usb.c | 27 |
1 files changed, 9 insertions, 18 deletions
diff --git a/drivers/staging/most/hdm-usb/hdm_usb.c b/drivers/staging/most/hdm-usb/hdm_usb.c index 65211d1824b7..6e94ee2b4fb3 100644 --- a/drivers/staging/most/hdm-usb/hdm_usb.c +++ b/drivers/staging/most/hdm-usb/hdm_usb.c @@ -649,8 +649,6 @@ static int hdm_configure_channel(struct most_interface *iface, int channel, { unsigned int num_frames; unsigned int frame_size; - unsigned int temp_size; - unsigned int tail_space; struct most_dev *mdev = to_mdev(iface); struct device *dev = &mdev->usb_device->dev; @@ -685,7 +683,6 @@ static int hdm_configure_channel(struct most_interface *iface, int channel, } mdev->padding_active[channel] = true; - temp_size = conf->buffer_size; frame_size = get_stream_frame_size(conf); if (frame_size == 0 || frame_size > USB_MTU) { @@ -693,25 +690,19 @@ static int hdm_configure_channel(struct most_interface *iface, int channel, return -EINVAL; } + num_frames = conf->buffer_size / frame_size; + if (conf->buffer_size % frame_size) { - u16 tmp_val; - - tmp_val = conf->buffer_size / frame_size; - conf->buffer_size = tmp_val * frame_size; - dev_notice(dev, - "Channel %d - rounding buffer size to %d bytes, channel config says %d bytes\n", - channel, - conf->buffer_size, - temp_size); - } + u16 old_size = conf->buffer_size; - num_frames = conf->buffer_size / frame_size; - tail_space = num_frames * (USB_MTU - frame_size); - temp_size += tail_space; + conf->buffer_size = num_frames * frame_size; + dev_warn(dev, "%s: fixed buffer size (%d -> %d)\n", + mdev->suffix[channel], old_size, conf->buffer_size); + } /* calculate extra length to comply w/ HW padding */ - conf->extra_len = (DIV_ROUND_UP(temp_size, USB_MTU) * USB_MTU) - - conf->buffer_size; + conf->extra_len = num_frames * (USB_MTU - frame_size); + exit: mdev->conf[channel] = *conf; if (conf->data_type == MOST_CH_ASYNC) { |