udlfb: Search config descriptor if not at device level

For at least one DisplayLink device, the vendor-specific information can
be found in the config descriptor instead of as a separate, device-level
descriptor.  This patch searches the current interface (of the current
config descriptor) for the DL vendor-specific descriptor.

Signed-off-by: Andrew Kephart <akephart@akephart.org>
Signed-off-by: Bernie Thompson <bernie@plugable.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
This commit is contained in:
Andrew Kephart 2011-08-21 13:34:13 -07:00 committed by Florian Tobias Schandinat
parent 58e7c3b001
commit f2e1fc9d5d

View File

@ -1479,21 +1479,30 @@ static int dlfb_select_std_channel(struct dlfb_data *dev)
}
static int dlfb_parse_vendor_descriptor(struct dlfb_data *dev,
struct usb_device *usbdev)
struct usb_interface *interface)
{
char *desc;
char *buf;
char *desc_end;
u8 total_len = 0;
int total_len = 0;
buf = kzalloc(MAX_VENDOR_DESCRIPTOR_SIZE, GFP_KERNEL);
if (!buf)
return false;
desc = buf;
total_len = usb_get_descriptor(usbdev, 0x5f, /* vendor specific */
0, desc, MAX_VENDOR_DESCRIPTOR_SIZE);
total_len = usb_get_descriptor(interface_to_usbdev(interface),
0x5f, /* vendor specific */
0, desc, MAX_VENDOR_DESCRIPTOR_SIZE);
/* if not found, look in configuration descriptor */
if (total_len < 0) {
if (0 == usb_get_extra_descriptor(interface->cur_altsetting,
0x5f, &desc))
total_len = (int) desc[0];
}
if (total_len > 5) {
pr_info("vendor descriptor length:%x data:%02x %02x %02x %02x" \
"%02x %02x %02x %02x %02x %02x %02x\n",
@ -1534,6 +1543,8 @@ static int dlfb_parse_vendor_descriptor(struct dlfb_data *dev,
}
desc += length;
}
} else {
pr_info("vendor descriptor not available (%d)\n", total_len);
}
goto success;
@ -1583,7 +1594,7 @@ static int dlfb_usb_probe(struct usb_interface *interface,
dev->sku_pixel_limit = 2048 * 1152; /* default to maximum */
if (!dlfb_parse_vendor_descriptor(dev, usbdev)) {
if (!dlfb_parse_vendor_descriptor(dev, interface)) {
pr_err("firmware not recognized. Assume incompatible device\n");
goto error;
}