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path: root/drivers/media/rc/iguanair.c
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Diffstat (limited to 'drivers/media/rc/iguanair.c')
-rw-r--r--drivers/media/rc/iguanair.c31
1 files changed, 16 insertions, 15 deletions
diff --git a/drivers/media/rc/iguanair.c b/drivers/media/rc/iguanair.c
index fdae05c4f377..627ddfd61980 100644
--- a/drivers/media/rc/iguanair.c
+++ b/drivers/media/rc/iguanair.c
@@ -286,10 +286,10 @@ static int iguanair_receiver(struct iguanair *ir, bool enable)
}
/*
- * The iguana ir creates the carrier by busy spinning after each pulse or
- * space. This is counted in CPU cycles, with the CPU running at 24MHz. It is
+ * The iguanair creates the carrier by busy spinning after each half period.
+ * This is counted in CPU cycles, with the CPU running at 24MHz. It is
* broken down into 7-cycles and 4-cyles delays, with a preference for
- * 4-cycle delays.
+ * 4-cycle delays, minus the overhead of the loop itself (cycle_overhead).
*/
static int iguanair_set_tx_carrier(struct rc_dev *dev, uint32_t carrier)
{
@@ -316,7 +316,14 @@ static int iguanair_set_tx_carrier(struct rc_dev *dev, uint32_t carrier)
sevens = (4 - cycles) & 3;
fours = (cycles - sevens * 7) / 4;
- /* magic happens here */
+ /*
+ * The firmware interprets these values as a relative offset
+ * for a branch. Immediately following the branches, there
+ * 4 instructions of 7 cycles (2 bytes each) and 110
+ * instructions of 4 cycles (1 byte each). A relative branch
+ * of 0 will execute all of them, branch further for less
+ * cycle burning.
+ */
ir->packet->busy7 = (4 - sevens) * 2;
ir->packet->busy4 = 110 - fours;
}
@@ -357,20 +364,14 @@ static int iguanair_tx(struct rc_dev *dev, unsigned *txbuf, unsigned count)
rc = -EINVAL;
goto out;
}
- while (periods > 127) {
- ir->packet->payload[size++] = 127 | space;
- periods -= 127;
+ while (periods) {
+ unsigned p = min(periods, 127u);
+ ir->packet->payload[size++] = p | space;
+ periods -= p;
}
-
- ir->packet->payload[size++] = periods | space;
space ^= 0x80;
}
- if (count == 0) {
- rc = -EINVAL;
- goto out;
- }
-
ir->packet->header.start = 0;
ir->packet->header.direction = DIR_OUT;
ir->packet->header.cmd = CMD_SEND;
@@ -494,7 +495,7 @@ static int iguanair_probe(struct usb_interface *intf,
usb_to_input_id(ir->udev, &rc->input_id);
rc->dev.parent = &intf->dev;
rc->driver_type = RC_DRIVER_IR_RAW;
- rc->allowed_protos = RC_BIT_ALL;
+ rc_set_allowed_protocols(rc, RC_BIT_ALL);
rc->priv = ir;
rc->open = iguanair_open;
rc->close = iguanair_close;