From 5866d9e3b7ecdf96a6089d12bb65736d7c473bce Mon Sep 17 00:00:00 2001 From: Jason Gerecke Date: Sat, 19 Apr 2014 13:46:40 -0700 Subject: [PATCH] Input: wacom - use full 32-bit HID Usage value in switch statement A HID Usage is a 32-bit value: an upper 16-bit "page" and a lower 16-bit ID. While the two halves are normally reported seperately, only the combination uniquely idenfifes a particular HID Usage. The existing code performs the comparison in two steps, first performing a switch on the ID and then verifying the page within each case. While this works fine, it is very akward to handle two Usages that share a single ID, such as HID_USAGE_PRESSURE and HID_USAGE_X because the case statement can only have a single identifier. To work around this, we now check the full 32-bit HID Usage directly rather than first checking the ID and then the page. This allows the switch statement to have distinct cases for e.g. HID_USAGE_PRESSURE and HID_USAGE_X. Signed-off-by: Jason Gerecke Tested-by: Aaron Skomra Reviewed-by: Carl Worth Signed-off-by: Dmitry Torokhov --- drivers/input/tablet/wacom_sys.c | 225 ++++++++++++++----------------- 1 file changed, 103 insertions(+), 122 deletions(-) diff --git a/drivers/input/tablet/wacom_sys.c b/drivers/input/tablet/wacom_sys.c index b16ebef5b911..5be617755461 100644 --- a/drivers/input/tablet/wacom_sys.c +++ b/drivers/input/tablet/wacom_sys.c @@ -22,23 +22,17 @@ #define HID_USAGE_PAGE_DIGITIZER 0x0d #define HID_USAGE_PAGE_DESKTOP 0x01 #define HID_USAGE 0x09 -#define HID_USAGE_X 0x30 -#define HID_USAGE_Y 0x31 -#define HID_USAGE_X_TILT 0x3d -#define HID_USAGE_Y_TILT 0x3e -#define HID_USAGE_FINGER 0x22 -#define HID_USAGE_STYLUS 0x20 -#define HID_USAGE_CONTACTMAX 0x55 +#define HID_USAGE_X ((HID_USAGE_PAGE_DESKTOP << 16) | 0x30) +#define HID_USAGE_Y ((HID_USAGE_PAGE_DESKTOP << 16) | 0x31) +#define HID_USAGE_X_TILT ((HID_USAGE_PAGE_DIGITIZER << 16) | 0x3d) +#define HID_USAGE_Y_TILT ((HID_USAGE_PAGE_DIGITIZER << 16) | 0x3e) +#define HID_USAGE_FINGER ((HID_USAGE_PAGE_DIGITIZER << 16) | 0x22) +#define HID_USAGE_STYLUS ((HID_USAGE_PAGE_DIGITIZER << 16) | 0x20) +#define HID_USAGE_CONTACTMAX ((HID_USAGE_PAGE_DIGITIZER << 16) | 0x55) #define HID_COLLECTION 0xa1 #define HID_COLLECTION_LOGICAL 0x02 #define HID_COLLECTION_END 0xc0 -enum { - WCM_UNDEFINED = 0, - WCM_DESKTOP, - WCM_DIGITIZER, -}; - struct hid_descriptor { struct usb_descriptor_header header; __le16 bcdHID; @@ -305,7 +299,7 @@ static int wacom_parse_hid(struct usb_interface *intf, char limit = 0; /* result has to be defined as int for some devices */ int result = 0, touch_max = 0; - int i = 0, usage = WCM_UNDEFINED, finger = 0, pen = 0; + int i = 0, page = 0, finger = 0, pen = 0; unsigned char *report; report = kzalloc(hid_desc->wDescriptorLength, GFP_KERNEL); @@ -332,134 +326,121 @@ static int wacom_parse_hid(struct usb_interface *intf, switch (report[i]) { case HID_USAGE_PAGE: - switch (report[i + 1]) { - case HID_USAGE_PAGE_DIGITIZER: - usage = WCM_DIGITIZER; - i++; - break; - - case HID_USAGE_PAGE_DESKTOP: - usage = WCM_DESKTOP; - i++; - break; - } + page = report[i + 1]; + i++; break; case HID_USAGE: - switch (report[i + 1]) { + switch (page << 16 | report[i + 1]) { case HID_USAGE_X: - if (usage == WCM_DESKTOP) { - if (finger) { - features->device_type = BTN_TOOL_FINGER; - /* touch device at least supports one touch point */ - touch_max = 1; - switch (features->type) { - case TABLETPC2FG: - features->pktlen = WACOM_PKGLEN_TPC2FG; - break; + if (finger) { + features->device_type = BTN_TOOL_FINGER; + /* touch device at least supports one touch point */ + touch_max = 1; + switch (features->type) { + case TABLETPC2FG: + features->pktlen = WACOM_PKGLEN_TPC2FG; + break; - case MTSCREEN: - case WACOM_24HDT: - features->pktlen = WACOM_PKGLEN_MTOUCH; - break; + case MTSCREEN: + case WACOM_24HDT: + features->pktlen = WACOM_PKGLEN_MTOUCH; + break; - case MTTPC: - features->pktlen = WACOM_PKGLEN_MTTPC; - break; + case MTTPC: + features->pktlen = WACOM_PKGLEN_MTTPC; + break; - case BAMBOO_PT: - features->pktlen = WACOM_PKGLEN_BBTOUCH; - break; + case BAMBOO_PT: + features->pktlen = WACOM_PKGLEN_BBTOUCH; + break; - default: - features->pktlen = WACOM_PKGLEN_GRAPHIRE; - break; - } + default: + features->pktlen = WACOM_PKGLEN_GRAPHIRE; + break; + } - switch (features->type) { - case BAMBOO_PT: - features->x_phy = - get_unaligned_le16(&report[i + 5]); - features->x_max = - get_unaligned_le16(&report[i + 8]); - i += 15; - break; + switch (features->type) { + case BAMBOO_PT: + features->x_phy = + get_unaligned_le16(&report[i + 5]); + features->x_max = + get_unaligned_le16(&report[i + 8]); + i += 15; + break; - case WACOM_24HDT: - features->x_max = - get_unaligned_le16(&report[i + 3]); - features->x_phy = - get_unaligned_le16(&report[i + 8]); - features->unit = report[i - 1]; - features->unitExpo = report[i - 3]; - i += 12; - break; - - default: - features->x_max = - get_unaligned_le16(&report[i + 3]); - features->x_phy = - get_unaligned_le16(&report[i + 6]); - features->unit = report[i + 9]; - features->unitExpo = report[i + 11]; - i += 12; - break; - } - } else if (pen) { - /* penabled only accepts exact bytes of data */ - if (features->type >= TABLETPC) - features->pktlen = WACOM_PKGLEN_GRAPHIRE; - features->device_type = BTN_TOOL_PEN; + case WACOM_24HDT: features->x_max = get_unaligned_le16(&report[i + 3]); - i += 4; + features->x_phy = + get_unaligned_le16(&report[i + 8]); + features->unit = report[i - 1]; + features->unitExpo = report[i - 3]; + i += 12; + break; + + default: + features->x_max = + get_unaligned_le16(&report[i + 3]); + features->x_phy = + get_unaligned_le16(&report[i + 6]); + features->unit = report[i + 9]; + features->unitExpo = report[i + 11]; + i += 12; + break; } + } else if (pen) { + /* penabled only accepts exact bytes of data */ + if (features->type >= TABLETPC) + features->pktlen = WACOM_PKGLEN_GRAPHIRE; + features->device_type = BTN_TOOL_PEN; + features->x_max = + get_unaligned_le16(&report[i + 3]); + i += 4; } break; case HID_USAGE_Y: - if (usage == WCM_DESKTOP) { - if (finger) { - switch (features->type) { - case TABLETPC2FG: - case MTSCREEN: - case MTTPC: - features->y_max = - get_unaligned_le16(&report[i + 3]); - features->y_phy = - get_unaligned_le16(&report[i + 6]); - i += 7; - break; - - case WACOM_24HDT: - features->y_max = - get_unaligned_le16(&report[i + 3]); - features->y_phy = - get_unaligned_le16(&report[i - 2]); - i += 7; - break; - - case BAMBOO_PT: - features->y_phy = - get_unaligned_le16(&report[i + 3]); - features->y_max = - get_unaligned_le16(&report[i + 6]); - i += 12; - break; - - default: - features->y_max = - features->x_max; - features->y_phy = - get_unaligned_le16(&report[i + 3]); - i += 4; - break; - } - } else if (pen) { + if (finger) { + switch (features->type) { + case TABLETPC2FG: + case MTSCREEN: + case MTTPC: features->y_max = get_unaligned_le16(&report[i + 3]); + features->y_phy = + get_unaligned_le16(&report[i + 6]); + i += 7; + break; + + case WACOM_24HDT: + features->y_max = + get_unaligned_le16(&report[i + 3]); + features->y_phy = + get_unaligned_le16(&report[i - 2]); + i += 7; + break; + + case BAMBOO_PT: + features->y_phy = + get_unaligned_le16(&report[i + 3]); + features->y_max = + get_unaligned_le16(&report[i + 6]); + i += 12; + break; + + default: + features->y_max = + features->x_max; + features->y_phy = + get_unaligned_le16(&report[i + 3]); i += 4; + break; } + } else if (pen) { + features->y_max = + get_unaligned_le16(&report[i + 3]); + i += 4; } break; @@ -489,7 +470,7 @@ static int wacom_parse_hid(struct usb_interface *intf, case HID_COLLECTION_END: /* reset UsagePage and Finger */ - finger = usage = 0; + finger = page = 0; break; case HID_COLLECTION: