[PATCH v2] HID: leave dev_rdesc unmodified and use it for comparisons
flat view
STALE5151d
From: Kevin Daughtridge <hidden>
Date: 2012-09-19 02:36:40
Also in:
lkml
The dev_rdesc member of the hid_device structure is meant to store the original report descriptor received from the device, but it is currently passed to any report_fixup method before it is copied to the rdesc member. This patch moves the kmemdup to before, not after, the report_fixup call, keeping dev_rdesc unchanged. usbhid's hid_post_reset checks the report descriptor currently returned by the device against a descriptor that may have been modified by a driver's report_fixup method. That leaves some devices nonfunctional after a resume, with a "reset_resume error 1" reported. This patch checks the new descriptor against the unmodified dev_rdesc instead. BugLink:http://bugs.launchpad.net/bugs/1049623 Signed-off-by: Kevin Daughtridge<redacted> ---
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c@@ -775,12 +775,14 @@ int hid_open_report(struct hid_device *d return -ENODEV; size = device->dev_rsize; + start = kmemdup(start, size, GFP_KERNEL); + if (start == NULL) + return -ENOMEM; + if (device->driver->report_fixup) start = device->driver->report_fixup(device, start, &size); - device->rdesc = kmemdup(start, size, GFP_KERNEL); - if (device->rdesc == NULL) - return -ENOMEM; + device->rdesc = start; device->rsize = size; parser = vzalloc(sizeof(struct hid_parser)); --- a/drivers/hid/usbhid/hid-core.c +++ b/drivers/hid/usbhid/hid-core.c
@@ -1436,7 +1436,7 @@ static int hid_post_reset(struct usb_int kfree(rdesc); return 1; } - status = memcmp(rdesc, hid->rdesc, hid->rsize); + status = memcmp(rdesc, hid->dev_rdesc, hid->rsize); kfree(rdesc); if (status != 0) { dbg_hid("report descriptor changed\n");