forked from rpms/kernel
61 lines
2.1 KiB
Diff
61 lines
2.1 KiB
Diff
Bugzilla: 1090161
|
|
Upstream-status: sent https://patchwork.kernel.org/patch/4055781/
|
|
|
|
From patchwork Thu Apr 24 22:26:38 2014
|
|
Content-Type: text/plain; charset="utf-8"
|
|
MIME-Version: 1.0
|
|
Content-Transfer-Encoding: 7bit
|
|
Subject: HID: rmi: do not fetch more than 16 bytes in a query
|
|
From: Benjamin Tissoires <benjamin.tissoires@redhat.com>
|
|
X-Patchwork-Id: 4055781
|
|
Message-Id: <1398378398-24825-1-git-send-email-benjamin.tissoires@redhat.com>
|
|
To: Andrew Duggan <aduggan@synaptics.com>,
|
|
Christopher Heiny <cheiny@synaptics.com>,
|
|
Jiri Kosina <jkosina@suse.cz>, linux-input@vger.kernel.org,
|
|
linux-kernel@vger.kernel.org
|
|
Date: Thu, 24 Apr 2014 18:26:38 -0400
|
|
|
|
A firmware bug is present on the XPS Haswell edition which silently
|
|
split the request in two responses when the caller ask for a read of
|
|
more than 16 bytes.
|
|
The FW sends the first 16 then the 4 next, but it says that it answered
|
|
the 20 bytes in the first report.
|
|
|
|
This occurs only on the retrieving of the min/max of X and Y of the F11
|
|
function.
|
|
We only use the first 10 bytes of the Ctrl register, so we can get only
|
|
those 10 bytes to prevent the bug from happening.
|
|
|
|
Resolves:
|
|
https://bugzilla.redhat.com/show_bug.cgi?id=1090161
|
|
|
|
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
|
|
|
|
---
|
|
drivers/hid/hid-rmi.c | 11 ++++++++---
|
|
1 file changed, 8 insertions(+), 3 deletions(-)
|
|
|
|
diff --git a/drivers/hid/hid-rmi.c b/drivers/hid/hid-rmi.c
|
|
index 7da9509..cee89c9 100644
|
|
--- a/drivers/hid/hid-rmi.c
|
|
+++ b/drivers/hid/hid-rmi.c
|
|
@@ -613,10 +613,15 @@ static int rmi_populate_f11(struct hid_device *hdev)
|
|
}
|
|
}
|
|
|
|
- /* retrieve the ctrl registers */
|
|
- ret = rmi_read_block(hdev, data->f11.control_base_addr, buf, 20);
|
|
+ /*
|
|
+ * retrieve the ctrl registers
|
|
+ * the ctrl register has a size of 20 but a fw bug split it into 16 + 4,
|
|
+ * and there is no way to know if the first 20 bytes are here or not.
|
|
+ * We use only the first 10 bytes, so get only them.
|
|
+ */
|
|
+ ret = rmi_read_block(hdev, data->f11.control_base_addr, buf, 10);
|
|
if (ret) {
|
|
- hid_err(hdev, "can not read ctrl block of size 20: %d.\n", ret);
|
|
+ hid_err(hdev, "can not read ctrl block of size 10: %d.\n", ret);
|
|
return ret;
|
|
}
|
|
|