[PATCH 3.12 10/56] HID: chicony: Add support for Acer Aspire Switch 12

[Jiri Slaby <jslaby@suse.cz>]

From: Николай Кудрявцев <nkudriavtsev@gmail.com>

3.12-stable review patch.  If anyone has any objections, please let me know.

===============

commit 9a1d78a3780e0e37eeff11b377fc5fbb01446a36 upstream.

Acer Aspire Switch 12 keyboard Chicony's controller reports too big usage
index on the 1st interface. The patch fixes the report. The work based on
solution from drivers/hid/hid-holtek-mouse.c

Bug report: https://bugzilla.kernel.org/show_bug.cgi?id=101721

Signed-off-by: Nicholas Kudriavtsev <nkudriavtsev@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/hid/hid-chicony.c | 26 ++++++++++++++++++++++++++
 drivers/hid/hid-core.c    |  1 +
 drivers/hid/hid-ids.h     |  1 +
 3 files changed, 28 insertions(+)

diff --git a/drivers/hid/hid-chicony.c b/drivers/hid/hid-chicony.c
index b613d5a79684..bc3cec199fee 100644
--- a/drivers/hid/hid-chicony.c
+++ b/drivers/hid/hid-chicony.c
@@ -20,6 +20,7 @@
 #include <linux/input.h>
 #include <linux/hid.h>
 #include <linux/module.h>
+#include <linux/usb.h>
 
 #include "hid-ids.h"
 
@@ -57,10 +58,34 @@ static int ch_input_mapping(struct hid_device *hdev, struct hid_input *hi,
 	return 1;
 }
 
+static __u8 *ch_switch12_report_fixup(struct hid_device *hdev, __u8 *rdesc,
+		unsigned int *rsize)
+{
+	struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
+	
+	if (intf->cur_altsetting->desc.bInterfaceNumber == 1) {
+		/* Change usage maximum and logical maximum from 0x7fff to
+		 * 0x2fff, so they don't exceed HID_MAX_USAGES */
+		switch (hdev->product) {
+		case USB_DEVICE_ID_CHICONY_ACER_SWITCH12:
+			if (*rsize >= 128 && rdesc[64] == 0xff && rdesc[65] == 0x7f
+					&& rdesc[69] == 0xff && rdesc[70] == 0x7f) {
+				hid_info(hdev, "Fixing up report descriptor\n");
+				rdesc[65] = rdesc[70] = 0x2f;
+			}
+			break;
+		}
+
+	}
+	return rdesc;
+}
+
+
 static const struct hid_device_id ch_devices[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CHICONY, USB_DEVICE_ID_CHICONY_TACTICAL_PAD) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CHICONY, USB_DEVICE_ID_CHICONY_WIRELESS2) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CHICONY, USB_DEVICE_ID_CHICONY_AK1D) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_CHICONY, USB_DEVICE_ID_CHICONY_ACER_SWITCH12) },
 	{ }
 };
 MODULE_DEVICE_TABLE(hid, ch_devices);
@@ -68,6 +93,7 @@ MODULE_DEVICE_TABLE(hid, ch_devices);
 static struct hid_driver ch_driver = {
 	.name = "chicony",
 	.id_table = ch_devices,
+	.report_fixup = ch_switch12_report_fixup,
 	.input_mapping = ch_input_mapping,
 };
 module_hid_driver(ch_driver);
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 6ae4df439d06..05867d1d8cdc 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1719,6 +1719,7 @@ static const struct hid_device_id hid_have_special_driver[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CHICONY, USB_DEVICE_ID_CHICONY_WIRELESS) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CHICONY, USB_DEVICE_ID_CHICONY_WIRELESS2) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CHICONY, USB_DEVICE_ID_CHICONY_AK1D) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_CHICONY, USB_DEVICE_ID_CHICONY_ACER_SWITCH12) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CREATIVELABS, USB_DEVICE_ID_PRODIKEYS_PCMIDI) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CYPRESS, USB_DEVICE_ID_CYPRESS_BARCODE_1) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_CYPRESS, USB_DEVICE_ID_CYPRESS_BARCODE_2) },
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 6a6b06ef31b1..555dc61d2eb3 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -224,6 +224,7 @@
 #define USB_DEVICE_ID_CHICONY_PIXART_USB_OPTICAL_MOUSE	0x1053
 #define USB_DEVICE_ID_CHICONY_WIRELESS2	0x1123
 #define USB_DEVICE_ID_CHICONY_AK1D	0x1125
+#define USB_DEVICE_ID_CHICONY_ACER_SWITCH12	0x1421
 
 #define USB_VENDOR_ID_CHUNGHWAT		0x2247
 #define USB_DEVICE_ID_CHUNGHWAT_MULTITOUCH	0x0001
-- 
2.9.0