From: Grant Likely grant.likely@secretlab.ca
commit 4f57cace81438cc873a96f9f13f08298815c9b51 upstream.
Some devices, particularly the 3DConnexion Spacemouse wireless 3D controllers, return more than just the battery capacity in the battery report. The Spacemouse devices return an additional byte with a device specific field. However, hidinput_query_battery_capacity() only requests a 2 byte transfer.
When a spacemouse is connected via USB (direct wire, no wireless dongle) and it returns a 3 byte report instead of the assumed 2 byte battery report the larger transfer confuses and frightens the USB subsystem which chooses to ignore the transfer. Then after 2 seconds assume the device has stopped responding and reset it. This can be reproduced easily by using a wired connection with a wireless spacemouse. The Spacemouse will enter a loop of resetting every 2 seconds which can be observed in dmesg.
This patch solves the problem by increasing the transfer request to 4 bytes instead of 2. The fix isn't particularly elegant, but it is simple and safe to backport to stable kernels. A further patch will follow to more elegantly handle battery reports that contain additional data.
Signed-off-by: Grant Likely grant.likely@secretlab.ca Cc: Darren Hart darren@dvhart.com Cc: Jiri Kosina jikos@kernel.org Cc: Benjamin Tissoires benjamin.tissoires@redhat.com Cc: stable@vger.kernel.org Tested-by: Darren Hart dvhart@infradead.org Signed-off-by: Jiri Kosina jkosina@suse.cz Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/hid/hid-input.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/hid/hid-input.c +++ b/drivers/hid/hid-input.c @@ -350,13 +350,13 @@ static int hidinput_query_battery_capaci u8 *buf; int ret;
- buf = kmalloc(2, GFP_KERNEL); + buf = kmalloc(4, GFP_KERNEL); if (!buf) return -ENOMEM;
- ret = hid_hw_raw_request(dev, dev->battery_report_id, buf, 2, + ret = hid_hw_raw_request(dev, dev->battery_report_id, buf, 4, dev->battery_report_type, HID_REQ_GET_REPORT); - if (ret != 2) { + if (ret < 2) { kfree(buf); return -ENODATA; }