Add patch to fix HID rmi driver from Benjamin Tissoires (rhbz 1090161)

1 files changed, 60 insertions, 0 deletions

diff --git a/HID-rmi-do-not-fetch-more-than-16-bytes-in-a-query.patch b/HID-rmi-do-not-fetch-more-than-16-bytes-in-a-query.patch
new file mode 100644
index 000000000..972a1b142
--- /dev/null
+++ b/HID-rmi-do-not-fetch-more-than-16-bytes-in-a-query.patch
@@ -0,0 +1,60 @@
+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;
+ 	}
+