[PATCH 1/3] HID: logitech-hidpp: detect HID++ 2.0 errors too

[Peter Wu <peter@lekensteyn.nl>]

Devices speaking HID++ 2.0 report a different error code (0xff). Detect
these errors too to avoid 5 second delays when the device reports an
error. Caught by... well, a bug in the QEMU emulation of this receiver.

Renamed fap to rap for HID++ 1.0 errors because it is more logical,
it has no functional difference.

Signed-off-by: Peter Wu <peter@lekensteyn.nl>
---
 drivers/hid/hid-logitech-hidpp.c | 17 ++++++++++++++---
 1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
index 2f420c0..ae23dec 100644
--- a/drivers/hid/hid-logitech-hidpp.c
+++ b/drivers/hid/hid-logitech-hidpp.c
@@ -105,6 +105,7 @@ struct hidpp_device {
 };
 
 
+/* HID++ 1.0 error codes */
 #define HIDPP_ERROR				0x8f
 #define HIDPP_ERROR_SUCCESS			0x00
 #define HIDPP_ERROR_INVALID_SUBID		0x01
@@ -119,6 +120,8 @@ struct hidpp_device {
 #define HIDPP_ERROR_REQUEST_UNAVAILABLE		0x0a
 #define HIDPP_ERROR_INVALID_PARAM_VALUE		0x0b
 #define HIDPP_ERROR_WRONG_PIN_CODE		0x0c
+/* HID++ 2.0 error codes */
+#define HIDPP20_ERROR				0xff
 
 static void hidpp_connect_event(struct hidpp_device *hidpp_dev);
 
@@ -192,9 +195,16 @@ static int hidpp_send_message_sync(struct hidpp_device *hidpp,
 	}
 
 	if (response->report_id == REPORT_ID_HIDPP_SHORT &&
-	    response->fap.feature_index == HIDPP_ERROR) {
+	    response->rap.sub_id == HIDPP_ERROR) {
+		ret = response->rap.params[1];
+		dbg_hid("%s:got hidpp error %02X\n", __func__, ret);
+		goto exit;
+	}
+
+	if (response->report_id == REPORT_ID_HIDPP_LONG &&
+	    response->fap.feature_index == HIDPP20_ERROR) {
 		ret = response->fap.params[1];
-		dbg_hid("__hidpp_send_report got hidpp error %02X\n", ret);
+		dbg_hid("%s:got hidpp 2.0 error %02X\n", __func__, ret);
 		goto exit;
 	}
 
@@ -271,7 +281,8 @@ static inline bool hidpp_match_answer(struct hidpp_report *question,
 static inline bool hidpp_match_error(struct hidpp_report *question,
 		struct hidpp_report *answer)
 {
-	return (answer->fap.feature_index == HIDPP_ERROR) &&
+	return ((answer->rap.sub_id == HIDPP_ERROR) ||
+	    (answer->fap.feature_index == HIDPP20_ERROR)) &&
 	    (answer->fap.funcindex_clientid == question->fap.feature_index) &&
 	    (answer->fap.params[0] == question->fap.funcindex_clientid);
 }
-- 
2.1.3