media: lirc: lirc daemon fails to detect raw IR device

Since commit 9b6192589be7 ("media: lirc: implement scancode sending"),
and commit de142c324106 ("media: lirc: implement reading scancode")
the lirc features ioctl for raw IR devices advertises two modes for
sending and receiving.

The lirc daemon now fails to detect a raw IR device, both for transmit
and receive.

To fix this, do not advertise the scancode mode in the lirc features
for raw IR devices (however do keep it for scancode devices). The mode
can still be used via the LIRC_SET_{REC,SEND}_MODE ioctl.

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

Documentation/media/uapi/rc/lirc-get-features.rst

@@ -55,8 +55,11 @@ LIRC features
 
 ``LIRC_CAN_REC_MODE2``
 
-    The driver is capable of receiving using
-    :ref:`LIRC_MODE_MODE2 <lirc-mode-MODE2>`.
+    This is raw IR driver for receiving. This means that
+    :ref:`LIRC_MODE_MODE2 <lirc-mode-MODE2>` is used. This also implies
+    that :ref:`LIRC_MODE_SCANCODE <lirc-mode-SCANCODE>` is also supported,
+    as long as the kernel is recent enough. Use the
+    :ref:`lirc_set_rec_mode` to switch modes.
 
 .. _LIRC-CAN-REC-LIRCCODE:
 
@@ -68,9 +71,8 @@ LIRC features
 
 ``LIRC_CAN_REC_SCANCODE``
 
-    The driver is capable of receiving using
-    :ref:`LIRC_MODE_SCANCODE <lirc-mode-SCANCODE>`.
-
+    This is a scancode driver for receiving. This means that
+    :ref:`LIRC_MODE_SCANCODE <lirc-mode-SCANCODE>` is used.
 
 .. _LIRC-CAN-SET-SEND-CARRIER:
 
@@ -164,7 +166,10 @@ LIRC features
 ``LIRC_CAN_SEND_PULSE``
 
     The driver supports sending (also called as IR blasting or IR TX) using
-    :ref:`LIRC_MODE_PULSE <lirc-mode-pulse>`.
+    :ref:`LIRC_MODE_PULSE <lirc-mode-pulse>`. This implies that
+    :ref:`LIRC_MODE_SCANCODE <lirc-mode-SCANCODE>` is also supported for
+    transmit, as long as the kernel is recent enough. Use the
+    :ref:`lirc_set_send_mode` to switch modes.
 
 .. _LIRC-CAN-SEND-MODE2:
 
@@ -179,13 +184,6 @@ LIRC features
 
     Unused. Kept just to avoid breaking uAPI.
 
-.. _LIRC-CAN-SEND-SCANCODE:
-
-``LIRC_CAN_SEND_SCANCODE``
-
-    The driver supports sending (also called as IR blasting or IR TX) using
-    :ref:`LIRC_MODE_SCANCODE <lirc-mode-SCANCODE>`.
-
 
 Return Value
 ============

drivers/media/rc/lirc_dev.c

@@ -403,13 +403,13 @@ static long ir_lirc_ioctl(struct file *file, unsigned int cmd,
 			val |= LIRC_CAN_REC_SCANCODE;
 
 		if (dev->driver_type == RC_DRIVER_IR_RAW) {
-			val |= LIRC_CAN_REC_MODE2 | LIRC_CAN_REC_SCANCODE;
+			val |= LIRC_CAN_REC_MODE2;
 			if (dev->rx_resolution)
 				val |= LIRC_CAN_GET_REC_RESOLUTION;
 		}
 
 		if (dev->tx_ir) {
-			val |= LIRC_CAN_SEND_PULSE | LIRC_CAN_SEND_SCANCODE;
+			val |= LIRC_CAN_SEND_PULSE;
 			if (dev->s_tx_mask)
 				val |= LIRC_CAN_SET_TRANSMITTER_MASK;
 			if (dev->s_tx_carrier)