From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kevin Daughtridge Subject: [PATCH v2] HID: leave dev_rdesc unmodified and use it for comparisons Date: Tue, 18 Sep 2012 19:36:33 -0700 Message-ID: <50592FB1.7000800@kdau.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pb0-f46.google.com ([209.85.160.46]:38735 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753682Ab2ISCgg (ORCPT ); Tue, 18 Sep 2012 22:36:36 -0400 Received: by pbbrr13 with SMTP id rr13so1312976pbb.19 for ; Tue, 18 Sep 2012 19:36:36 -0700 (PDT) Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Jiri Kosina , linux-input@vger.kernel.org Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Henrik Rydberg , Kevin Daughtridge 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 --- --- 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");