V4L/DVB: ir-core: Add support for badly-implemented hardware decoders

A few hardware Remote Controller decoders, even using a standard protocol,
aren't able to provide the entire scancode. Due to that, the capability
of using other IR's are limited on those hardware.

Adds a way to indicate to ir-core what are the bits that the hardware
provides, from a scancode, allowing the addition of a complete IR table
to the kernel and allowing a limited support for changing the Remote
Controller on those devices.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 28 insertions, 2 deletions

diff --git a/drivers/media/video/cx88/cx88-input.c b/drivers/media/video/cx88/cx88-input.c
index 7ddc8bb463f8..76733349c6cc 100644
--- a/drivers/media/video/cx88/cx88-input.c
+++ b/drivers/media/video/cx88/cx88-input.c
@@ -248,6 +248,9 @@ int cx88_ir_init(struct cx88_core *core, struct pci_dev *pci)
         char *ir_codes = NULL;
         u64 ir_type = IR_TYPE_OTHER;
         int err = -ENOMEM;
+        u32 hardware_mask = 0;  /* For devices with a hardware mask, when
+                                 * used with a full-code IR table
+                                 */
 
         ir = kzalloc(sizeof(*ir), GFP_KERNEL);
         input_dev = input_allocate_device();
@@ -314,11 +317,18 @@ int cx88_ir_init(struct cx88_core *core, struct pci_dev *pci)
                 break;
         case CX88_BOARD_PROLINK_PLAYTVPVR:
         case CX88_BOARD_PIXELVIEW_PLAYTV_ULTRA_PRO:
-                ir_codes = RC_MAP_PIXELVIEW;
+                /*
+                 * It seems that this hardware is paired with NEC extended
+                 * address 0x866b. So, unfortunately, its usage with other
+                 * IR's with different address won't work. Still, there are
+                 * other IR's from the same manufacturer that works, like the
+                 * 002-T mini RC, provided with newer PV hardware
+                 */
+                ir_codes = RC_MAP_PIXELVIEW_MK12;
                 ir->gpio_addr = MO_GP1_IO;
-                ir->mask_keycode = 0x1f;        /* Only command is retrieved */
                 ir->mask_keyup = 0x80;
                 ir->polling = 10; /* ms */
+                hardware_mask = 0x3f;   /* Hardware returns only 6 bits from command part */
                 break;
         case CX88_BOARD_PROLINK_PV_8000GT:
         case CX88_BOARD_PROLINK_PV_GLOBAL_XTREME:
@@ -410,6 +420,21 @@ int cx88_ir_init(struct cx88_core *core, struct pci_dev *pci)
                 goto err_out_free;
         }
 
+        /*
+         * The usage of mask_keycode were very convenient, due to several
+         * reasons. Among others, the scancode tables were using the scancode
+         * as the index elements. So, the less bits it was used, the smaller
+         * the table were stored. After the input changes, the better is to use
+         * the full scancodes, since it allows replacing the IR remote by
+         * another one. Unfortunately, there are still some hardware, like
+         * Pixelview Ultra Pro, where only part of the scancode is sent via
+         * GPIO. So, there's no way to get the full scancode. Due to that,
+         * hardware_mask were introduced here: it represents those hardware
+         * that has such limits.
+         */
+        if (hardware_mask && !ir->mask_keycode)
+                ir->mask_keycode = hardware_mask;
+
         /* init input device */
         snprintf(ir->name, sizeof(ir->name), "cx88 IR (%s)", core->board.name);
         snprintf(ir->phys, sizeof(ir->phys), "pci-%s/ir0", pci_name(pci));
@@ -437,6 +462,7 @@ int cx88_ir_init(struct cx88_core *core, struct pci_dev *pci)
         ir->props.priv = core;
         ir->props.open = cx88_ir_open;
         ir->props.close = cx88_ir_close;
+        ir->props.scanmask = hardware_mask;
 
         /* all done */
         err = ir_input_register(ir->input, ir_codes, &ir->props, MODULE_NAME);