V4L/DVB: ir-core: Add logic to decode IR protocols at the IR core

Adds a method to pass IR raw pulse/code events into ir-core. This is
needed in order to support LIRC. It also helps to move common code
from the drivers into the core.

In order to allow testing, it implements a simple NEC protocol decoder
at ir-nec-decoder.c file. The logic is about the same used at saa7134
driver that handles Avermedia M135A and Encore FM53 boards.

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

1 files changed, 81 insertions, 4 deletions

diff --git a/drivers/media/video/saa7134/saa7134-input.c b/drivers/media/video/saa7134/saa7134-input.c
index 7e6f125e4e31..1a7cf9c8c68c 100644
--- a/drivers/media/video/saa7134/saa7134-input.c
+++ b/drivers/media/video/saa7134/saa7134-input.c
@@ -68,6 +68,7 @@ MODULE_PARM_DESC(disable_other_ir, "disable full codes of "
 /* Helper functions for RC5 and NEC decoding at GPIO16 or GPIO18 */
 static int saa7134_rc5_irq(struct saa7134_dev *dev);
 static int saa7134_nec_irq(struct saa7134_dev *dev);
+static int saa7134_raw_decode_irq(struct saa7134_dev *dev);
 static void nec_task(unsigned long data);
 static void saa7134_nec_timer(unsigned long data);
 
@@ -403,10 +404,12 @@ void saa7134_input_irq(struct saa7134_dev *dev)
 
         if (ir->nec_gpio) {
                 saa7134_nec_irq(dev);
-        } else if (!ir->polling && !ir->rc5_gpio) {
+        } else if (!ir->polling && !ir->rc5_gpio && !ir->raw_decode) {
                 build_key(dev);
         } else if (ir->rc5_gpio) {
                 saa7134_rc5_irq(dev);
+        } else if (ir->raw_decode) {
+                saa7134_raw_decode_irq(dev);
         }
 }
 
@@ -419,6 +422,23 @@ static void saa7134_input_timer(unsigned long data)
         mod_timer(&ir->timer, jiffies + msecs_to_jiffies(ir->polling));
 }
 
+void ir_raw_decode_timer_end(unsigned long data)
+{
+        struct saa7134_dev *dev = (struct saa7134_dev *)data;
+        struct card_ir *ir = dev->remote;
+        int rc;
+
+        /*
+         * FIXME: the IR key handling code should be called by the decoder,
+         * after implementing the repeat mode
+         */
+        rc = ir_raw_event_handle(dev->remote->dev);
+        if (rc >= 0) {
+                ir_input_keydown(ir->dev, &ir->ir, rc);
+                ir_input_nokey(ir->dev, &ir->ir);
+        }
+}
+
 void saa7134_ir_start(struct saa7134_dev *dev, struct card_ir *ir)
 {
         if (ir->running)
@@ -447,6 +467,11 @@ void saa7134_ir_start(struct saa7134_dev *dev, struct card_ir *ir)
                 setup_timer(&ir->timer_keyup, saa7134_nec_timer,
                             (unsigned long)dev);
                 tasklet_init(&ir->tlet, nec_task, (unsigned long)dev);
+        } else if (ir->raw_decode) {
+                /* set timer_end for code completion */
+                init_timer(&ir->timer_end);
+                ir->timer_end.function = ir_raw_decode_timer_end;
+                ir->timer_end.data = (unsigned long)dev;
         }
 }
 
@@ -462,6 +487,9 @@ void saa7134_ir_stop(struct saa7134_dev *dev)
                 del_timer_sync(&ir->timer_end);
         else if (ir->nec_gpio)
                 tasklet_kill(&ir->tlet);
+        else if (ir->raw_decode)
+                del_timer_sync(&ir->timer_end);
+
         ir->running = 0;
 }
 
@@ -509,6 +537,7 @@ int saa7134_input_init1(struct saa7134_dev *dev)
         int polling      = 0;
         int rc5_gpio     = 0;
         int nec_gpio     = 0;
+        int raw_decode   = 0;
         u64 ir_type = IR_TYPE_OTHER;
         int err;
 
@@ -574,7 +603,7 @@ int saa7134_input_init1(struct saa7134_dev *dev)
                 ir_codes     = &ir_codes_avermedia_m135a_rm_jx_table;
                 mask_keydown = 0x0040000;
                 mask_keycode = 0xffff;
-                nec_gpio     = 1;
+                raw_decode   = 1;
                 break;
         case SAA7134_BOARD_AVERMEDIA_777:
         case SAA7134_BOARD_AVERMEDIA_A16AR:
@@ -755,6 +784,7 @@ int saa7134_input_init1(struct saa7134_dev *dev)
         ir->polling      = polling;
         ir->rc5_gpio     = rc5_gpio;
         ir->nec_gpio     = nec_gpio;
+        ir->raw_decode   = raw_decode;
 
         /* init input device */
         snprintf(ir->name, sizeof(ir->name), "saa7134 IR (%s)",
@@ -762,7 +792,7 @@ int saa7134_input_init1(struct saa7134_dev *dev)
         snprintf(ir->phys, sizeof(ir->phys), "pci-%s/ir0",
                  pci_name(dev->pci));
 
-        if (ir_codes->ir_type != IR_TYPE_OTHER) {
+        if (ir_codes->ir_type != IR_TYPE_OTHER && !raw_decode) {
                 ir->props.allowed_protos = IR_TYPE_RC5 | IR_TYPE_NEC;
                 ir->props.priv = dev;
                 ir->props.change_protocol = saa7134_ir_change_protocol;
@@ -790,6 +820,11 @@ int saa7134_input_init1(struct saa7134_dev *dev)
         err = ir_input_register(ir->dev, ir_codes, &ir->props, MODULE_NAME);
         if (err)
                 goto err_out_stop;
+        if (ir_codes->ir_type != IR_TYPE_OTHER) {
+                err = ir_raw_event_register(ir->dev);
+                if (err)
+                        goto err_out_stop;
+        }
 
         saa7134_ir_start(dev, ir);
 
@@ -813,6 +848,7 @@ void saa7134_input_fini(struct saa7134_dev *dev)
                 return;
 
         saa7134_ir_stop(dev);
+        ir_raw_event_unregister(dev->remote->dev);
         ir_input_unregister(dev->remote->dev);
         kfree(dev->remote);
         dev->remote = NULL;
@@ -919,6 +955,48 @@ void saa7134_probe_i2c_ir(struct saa7134_dev *dev)
         i2c_new_device(&dev->i2c_adap, &info);
 }
 
+static int saa7134_raw_decode_irq(struct saa7134_dev *dev)
+{
+        struct card_ir  *ir = dev->remote;
+        unsigned long   timeout;
+        int count, pulse, oldpulse;
+
+        /* Disable IR IRQ line */
+        saa_clearl(SAA7134_IRQ2, SAA7134_IRQ2_INTE_GPIO18);
+
+        /* Generate initial event */
+        saa_clearb(SAA7134_GPIO_GPMODE3, SAA7134_GPIO_GPRESCAN);
+        saa_setb(SAA7134_GPIO_GPMODE3, SAA7134_GPIO_GPRESCAN);
+        pulse = saa_readl(SAA7134_GPIO_GPSTATUS0 >> 2) & ir->mask_keydown;
+        ir_raw_event_store(dev->remote->dev, pulse? IR_PULSE : IR_SPACE);
+
+#if 1
+        /* Wait up to 10 ms for event change */
+        oldpulse = pulse;
+        for (count = 0; count < 1000; count++)  {
+                udelay(10);
+                /* rising SAA7134_GPIO_GPRESCAN reads the status */
+                saa_clearb(SAA7134_GPIO_GPMODE3, SAA7134_GPIO_GPRESCAN);
+                saa_setb(SAA7134_GPIO_GPMODE3, SAA7134_GPIO_GPRESCAN);
+                pulse = saa_readl(SAA7134_GPIO_GPSTATUS0 >> 2)
+                        & ir->mask_keydown;
+                if (pulse != oldpulse)
+                        break;
+        }
+
+        /* Store final event */
+        ir_raw_event_store(dev->remote->dev, pulse? IR_PULSE : IR_SPACE);
+#endif
+        /* Wait 15 ms before deciding to do something else */
+        timeout = jiffies + jiffies_to_msecs(15);
+        mod_timer(&ir->timer_end, timeout);
+
+        /* Enable IR IRQ line */
+        saa_setl(SAA7134_IRQ2, SAA7134_IRQ2_INTE_GPIO18);
+
+        return 1;
+}
+
 static int saa7134_rc5_irq(struct saa7134_dev *dev)
 {
         struct card_ir *ir = dev->remote;
@@ -961,7 +1039,6 @@ static int saa7134_rc5_irq(struct saa7134_dev *dev)
         return 1;
 }
 
-
 /* On NEC protocol, One has 2.25 ms, and zero has 1.125 ms
    The first pulse (start) has 9 + 4.5 ms
  */