4 files changed, 216 insertions, 0 deletions

diff --git a/drivers/media/rc/Kconfig b/drivers/media/rc/Kconfig
index 904f11367c29..3b25887a9c09 100644
--- a/drivers/media/rc/Kconfig
+++ b/drivers/media/rc/Kconfig
@@ -106,6 +106,15 @@ config IR_SANYO_DECODER
            uses the Sanyo protocol (Sanyo, Aiwa, Chinon remotes),
            and you need software decoding support.
 
+config IR_SHARP_DECODER
+        tristate "Enable IR raw decoder for the Sharp protocol"
+        depends on RC_CORE
+        default y
+
+        ---help---
+           Enable this option if you have an infrared remote control which
+           uses the Sharp protocol, and you need software decoding support.
+
 config IR_MCE_KBD_DECODER
         tristate "Enable IR raw decoder for the MCE keyboard/mouse protocol"
         depends on RC_CORE
diff --git a/drivers/media/rc/Makefile b/drivers/media/rc/Makefile
index f4eb32c0a455..36dafed412dd 100644
--- a/drivers/media/rc/Makefile
+++ b/drivers/media/rc/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_IR_JVC_DECODER) += ir-jvc-decoder.o
 obj-$(CONFIG_IR_SONY_DECODER) += ir-sony-decoder.o
 obj-$(CONFIG_IR_RC5_SZ_DECODER) += ir-rc5-sz-decoder.o
 obj-$(CONFIG_IR_SANYO_DECODER) += ir-sanyo-decoder.o
+obj-$(CONFIG_IR_SHARP_DECODER) += ir-sharp-decoder.o
 obj-$(CONFIG_IR_MCE_KBD_DECODER) += ir-mce_kbd-decoder.o
 obj-$(CONFIG_IR_LIRC_CODEC) += ir-lirc-codec.o
 
diff --git a/drivers/media/rc/ir-sharp-decoder.c b/drivers/media/rc/ir-sharp-decoder.c
new file mode 100644
index 000000000000..4c17be5d68ba
--- /dev/null
+++ b/drivers/media/rc/ir-sharp-decoder.c
@@ -0,0 +1,200 @@
+/* ir-sharp-decoder.c - handle Sharp IR Pulse/Space protocol
+ *
+ * Copyright (C) 2013-2014 Imagination Technologies Ltd.
+ *
+ * Based on NEC decoder:
+ * Copyright (C) 2010 by Mauro Carvalho Chehab <mchehab@redhat.com>
+ *
+ * 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 <linux/module.h>
+#include "rc-core-priv.h"
+
+#define SHARP_NBITS             15
+#define SHARP_UNIT              40000  /* ns */
+#define SHARP_BIT_PULSE         (8    * SHARP_UNIT) /* 320us */
+#define SHARP_BIT_0_PERIOD      (25   * SHARP_UNIT) /* 1ms (680us space) */
+#define SHARP_BIT_1_PERIOD      (50   * SHARP_UNIT) /* 2ms (1680ms space) */
+#define SHARP_ECHO_SPACE        (1000 * SHARP_UNIT) /* 40 ms */
+#define SHARP_TRAILER_SPACE     (125  * SHARP_UNIT) /* 5 ms (even longer) */
+
+enum sharp_state {
+        STATE_INACTIVE,
+        STATE_BIT_PULSE,
+        STATE_BIT_SPACE,
+        STATE_TRAILER_PULSE,
+        STATE_ECHO_SPACE,
+        STATE_TRAILER_SPACE,
+};
+
+/**
+ * ir_sharp_decode() - Decode one Sharp pulse or space
+ * @dev:        the struct rc_dev descriptor of the device
+ * @duration:   the struct ir_raw_event descriptor of the pulse/space
+ *
+ * This function returns -EINVAL if the pulse violates the state machine
+ */
+static int ir_sharp_decode(struct rc_dev *dev, struct ir_raw_event ev)
+{
+        struct sharp_dec *data = &dev->raw->sharp;
+        u32 msg, echo, address, command, scancode;
+
+        if (!(dev->enabled_protocols & RC_BIT_SHARP))
+                return 0;
+
+        if (!is_timing_event(ev)) {
+                if (ev.reset)
+                        data->state = STATE_INACTIVE;
+                return 0;
+        }
+
+        IR_dprintk(2, "Sharp 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, SHARP_BIT_PULSE,
+                               SHARP_BIT_PULSE / 2))
+                        break;
+
+                data->count = 0;
+                data->pulse_len = ev.duration;
+                data->state = STATE_BIT_SPACE;
+                return 0;
+
+        case STATE_BIT_PULSE:
+                if (!ev.pulse)
+                        break;
+
+                if (!eq_margin(ev.duration, SHARP_BIT_PULSE,
+                               SHARP_BIT_PULSE / 2))
+                        break;
+
+                data->pulse_len = ev.duration;
+                data->state = STATE_BIT_SPACE;
+                return 0;
+
+        case STATE_BIT_SPACE:
+                if (ev.pulse)
+                        break;
+
+                data->bits <<= 1;
+                if (eq_margin(data->pulse_len + ev.duration, SHARP_BIT_1_PERIOD,
+                              SHARP_BIT_PULSE * 2))
+                        data->bits |= 1;
+                else if (!eq_margin(data->pulse_len + ev.duration,
+                                    SHARP_BIT_0_PERIOD, SHARP_BIT_PULSE * 2))
+                        break;
+                data->count++;
+
+                if (data->count == SHARP_NBITS ||
+                    data->count == SHARP_NBITS * 2)
+                        data->state = STATE_TRAILER_PULSE;
+                else
+                        data->state = STATE_BIT_PULSE;
+
+                return 0;
+
+        case STATE_TRAILER_PULSE:
+                if (!ev.pulse)
+                        break;
+
+                if (!eq_margin(ev.duration, SHARP_BIT_PULSE,
+                               SHARP_BIT_PULSE / 2))
+                        break;
+
+                if (data->count == SHARP_NBITS) {
+                        /* exp,chk bits should be 1,0 */
+                        if ((data->bits & 0x3) != 0x2)
+                                break;
+                        data->state = STATE_ECHO_SPACE;
+                } else {
+                        data->state = STATE_TRAILER_SPACE;
+                }
+                return 0;
+
+        case STATE_ECHO_SPACE:
+                if (ev.pulse)
+                        break;
+
+                if (!eq_margin(ev.duration, SHARP_ECHO_SPACE,
+                               SHARP_ECHO_SPACE / 4))
+                        break;
+
+                data->state = STATE_BIT_PULSE;
+
+                return 0;
+
+        case STATE_TRAILER_SPACE:
+                if (ev.pulse)
+                        break;
+
+                if (!geq_margin(ev.duration, SHARP_TRAILER_SPACE,
+                                SHARP_BIT_PULSE / 2))
+                        break;
+
+                /* Validate - command, ext, chk should be inverted in 2nd */
+                msg = (data->bits >> 15) & 0x7fff;
+                echo = data->bits & 0x7fff;
+                if ((msg ^ echo) != 0x3ff) {
+                        IR_dprintk(1,
+                                   "Sharp checksum error: received 0x%04x, 0x%04x\n",
+                                   msg, echo);
+                        break;
+                }
+
+                address = bitrev8((msg >> 7) & 0xf8);
+                command = bitrev8((msg >> 2) & 0xff);
+
+                scancode = address << 8 | command;
+                IR_dprintk(1, "Sharp scancode 0x%04x\n", scancode);
+
+                rc_keydown(dev, scancode, 0);
+                data->state = STATE_INACTIVE;
+                return 0;
+        }
+
+        IR_dprintk(1, "Sharp decode failed at count %d state %d (%uus %s)\n",
+                   data->count, data->state, TO_US(ev.duration),
+                   TO_STR(ev.pulse));
+        data->state = STATE_INACTIVE;
+        return -EINVAL;
+}
+
+static struct ir_raw_handler sharp_handler = {
+        .protocols      = RC_BIT_SHARP,
+        .decode         = ir_sharp_decode,
+};
+
+static int __init ir_sharp_decode_init(void)
+{
+        ir_raw_handler_register(&sharp_handler);
+
+        pr_info("IR Sharp protocol handler initialized\n");
+        return 0;
+}
+
+static void __exit ir_sharp_decode_exit(void)
+{
+        ir_raw_handler_unregister(&sharp_handler);
+}
+
+module_init(ir_sharp_decode_init);
+module_exit(ir_sharp_decode_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("James Hogan <james.hogan@imgtec.com>");
+MODULE_DESCRIPTION("Sharp IR protocol decoder");
diff --git a/drivers/media/rc/rc-core-priv.h b/drivers/media/rc/rc-core-priv.h
index 70a180bb0bd0..c40d6660acac 100644
--- a/drivers/media/rc/rc-core-priv.h
+++ b/drivers/media/rc/rc-core-priv.h
@@ -88,6 +88,12 @@ struct ir_raw_event_ctrl {
                 unsigned count;
                 u64 bits;
         } sanyo;
+        struct sharp_dec {
+                int state;
+                unsigned count;
+                u32 bits;
+                unsigned int pulse_len;
+        } sharp;
         struct mce_kbd_dec {
                 struct input_dev *idev;
                 struct timer_list rx_timeout;