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path: root/drivers/media/rc/ir-sony-decoder.c
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Diffstat (limited to 'drivers/media/rc/ir-sony-decoder.c')
-rw-r--r--drivers/media/rc/ir-sony-decoder.c181
1 files changed, 181 insertions, 0 deletions
diff --git a/drivers/media/rc/ir-sony-decoder.c b/drivers/media/rc/ir-sony-decoder.c
new file mode 100644
index 000000000000..a92de80c48db
--- /dev/null
+++ b/drivers/media/rc/ir-sony-decoder.c
@@ -0,0 +1,181 @@
+/* ir-sony-decoder.c - handle Sony IR Pulse/Space protocol
+ *
+ * Copyright (C) 2010 by David Härdeman <david@hardeman.nu>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/bitrev.h>
+#include "rc-core-priv.h"
+
+#define SONY_UNIT 600000 /* ns */
+#define SONY_HEADER_PULSE (4 * SONY_UNIT)
+#define SONY_HEADER_SPACE (1 * SONY_UNIT)
+#define SONY_BIT_0_PULSE (1 * SONY_UNIT)
+#define SONY_BIT_1_PULSE (2 * SONY_UNIT)
+#define SONY_BIT_SPACE (1 * SONY_UNIT)
+#define SONY_TRAILER_SPACE (10 * SONY_UNIT) /* minimum */
+
+enum sony_state {
+ STATE_INACTIVE,
+ STATE_HEADER_SPACE,
+ STATE_BIT_PULSE,
+ STATE_BIT_SPACE,
+ STATE_FINISHED,
+};
+
+/**
+ * ir_sony_decode() - Decode one Sony pulse or space
+ * @dev: the struct rc_dev descriptor of the device
+ * @ev: the struct ir_raw_event descriptor of the pulse/space
+ *
+ * This function returns -EINVAL if the pulse violates the state machine
+ */
+static int ir_sony_decode(struct rc_dev *dev, struct ir_raw_event ev)
+{
+ struct sony_dec *data = &dev->raw->sony;
+ u32 scancode;
+ u8 device, subdevice, function;
+
+ if (!(dev->raw->enabled_protocols & RC_TYPE_SONY))
+ return 0;
+
+ if (!is_timing_event(ev)) {
+ if (ev.reset)
+ data->state = STATE_INACTIVE;
+ return 0;
+ }
+
+ if (!geq_margin(ev.duration, SONY_UNIT, SONY_UNIT / 2))
+ goto out;
+
+ IR_dprintk(2, "Sony decode started at state %d (%uus %s)\n",
+ data->state, TO_US(ev.duration), TO_STR(ev.pulse));
+
+ switch (data->state) {
+
+ case STATE_INACTIVE:
+ if (!ev.pulse)
+ break;
+
+ if (!eq_margin(ev.duration, SONY_HEADER_PULSE, SONY_UNIT / 2))
+ break;
+
+ data->count = 0;
+ data->state = STATE_HEADER_SPACE;
+ return 0;
+
+ case STATE_HEADER_SPACE:
+ if (ev.pulse)
+ break;
+
+ if (!eq_margin(ev.duration, SONY_HEADER_SPACE, SONY_UNIT / 2))
+ break;
+
+ data->state = STATE_BIT_PULSE;
+ return 0;
+
+ case STATE_BIT_PULSE:
+ if (!ev.pulse)
+ break;
+
+ data->bits <<= 1;
+ if (eq_margin(ev.duration, SONY_BIT_1_PULSE, SONY_UNIT / 2))
+ data->bits |= 1;
+ else if (!eq_margin(ev.duration, SONY_BIT_0_PULSE, SONY_UNIT / 2))
+ break;
+
+ data->count++;
+ data->state = STATE_BIT_SPACE;
+ return 0;
+
+ case STATE_BIT_SPACE:
+ if (ev.pulse)
+ break;
+
+ if (!geq_margin(ev.duration, SONY_BIT_SPACE, SONY_UNIT / 2))
+ break;
+
+ decrease_duration(&ev, SONY_BIT_SPACE);
+
+ if (!geq_margin(ev.duration, SONY_UNIT, SONY_UNIT / 2)) {
+ data->state = STATE_BIT_PULSE;
+ return 0;
+ }
+
+ data->state = STATE_FINISHED;
+ /* Fall through */
+
+ case STATE_FINISHED:
+ if (ev.pulse)
+ break;
+
+ if (!geq_margin(ev.duration, SONY_TRAILER_SPACE, SONY_UNIT / 2))
+ break;
+
+ switch (data->count) {
+ case 12:
+ device = bitrev8((data->bits << 3) & 0xF8);
+ subdevice = 0;
+ function = bitrev8((data->bits >> 4) & 0xFE);
+ break;
+ case 15:
+ device = bitrev8((data->bits >> 0) & 0xFF);
+ subdevice = 0;
+ function = bitrev8((data->bits >> 7) & 0xFD);
+ break;
+ case 20:
+ device = bitrev8((data->bits >> 5) & 0xF8);
+ subdevice = bitrev8((data->bits >> 0) & 0xFF);
+ function = bitrev8((data->bits >> 12) & 0xFE);
+ break;
+ default:
+ IR_dprintk(1, "Sony invalid bitcount %u\n", data->count);
+ goto out;
+ }
+
+ scancode = device << 16 | subdevice << 8 | function;
+ IR_dprintk(1, "Sony(%u) scancode 0x%05x\n", data->count, scancode);
+ rc_keydown(dev, scancode, 0);
+ data->state = STATE_INACTIVE;
+ return 0;
+ }
+
+out:
+ IR_dprintk(1, "Sony decode failed at state %d (%uus %s)\n",
+ data->state, TO_US(ev.duration), TO_STR(ev.pulse));
+ data->state = STATE_INACTIVE;
+ return -EINVAL;
+}
+
+static struct ir_raw_handler sony_handler = {
+ .protocols = RC_TYPE_SONY,
+ .decode = ir_sony_decode,
+};
+
+static int __init ir_sony_decode_init(void)
+{
+ ir_raw_handler_register(&sony_handler);
+
+ printk(KERN_INFO "IR Sony protocol handler initialized\n");
+ return 0;
+}
+
+static void __exit ir_sony_decode_exit(void)
+{
+ ir_raw_handler_unregister(&sony_handler);
+}
+
+module_init(ir_sony_decode_init);
+module_exit(ir_sony_decode_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Härdeman <david@hardeman.nu>");
+MODULE_DESCRIPTION("Sony IR protocol decoder");
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