HID: chicony: Add support for Acer Aspire Switch 12

commit 9a1d78a3 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=101721Signed-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

@@ -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);

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) },

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