diff options
Diffstat (limited to 'drivers/media/rc/ir-sony-decoder.c')
| -rw-r--r-- | drivers/media/rc/ir-sony-decoder.c | 240 |
1 files changed, 240 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 000000000..bb25867ec --- /dev/null +++ b/drivers/media/rc/ir-sony-decoder.c @@ -0,0 +1,240 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* ir-sony-decoder.c - handle Sony IR Pulse/Space protocol + * + * Copyright (C) 2010 by David Härdeman <david@hardeman.nu> + */ + +#include <linux/bitrev.h> +#include <linux/module.h> +#include "rc-core-priv.h" + +#define SONY_UNIT 600 /* us */ +#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; + enum rc_proto protocol; + u32 scancode; + u8 device, subdevice, function; + + if (!is_timing_event(ev)) { + if (ev.overflow) + data->state = STATE_INACTIVE; + return 0; + } + + if (!geq_margin(ev.duration, SONY_UNIT, SONY_UNIT / 2)) + goto out; + + dev_dbg(&dev->dev, "Sony decode started at state %d (%uus %s)\n", + data->state, 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; + fallthrough; + + case STATE_FINISHED: + if (ev.pulse) + break; + + if (!geq_margin(ev.duration, SONY_TRAILER_SPACE, SONY_UNIT / 2)) + break; + + switch (data->count) { + case 12: + if (!(dev->enabled_protocols & RC_PROTO_BIT_SONY12)) + goto finish_state_machine; + + device = bitrev8((data->bits << 3) & 0xF8); + subdevice = 0; + function = bitrev8((data->bits >> 4) & 0xFE); + protocol = RC_PROTO_SONY12; + break; + case 15: + if (!(dev->enabled_protocols & RC_PROTO_BIT_SONY15)) + goto finish_state_machine; + + device = bitrev8((data->bits >> 0) & 0xFF); + subdevice = 0; + function = bitrev8((data->bits >> 7) & 0xFE); + protocol = RC_PROTO_SONY15; + break; + case 20: + if (!(dev->enabled_protocols & RC_PROTO_BIT_SONY20)) + goto finish_state_machine; + + device = bitrev8((data->bits >> 5) & 0xF8); + subdevice = bitrev8((data->bits >> 0) & 0xFF); + function = bitrev8((data->bits >> 12) & 0xFE); + protocol = RC_PROTO_SONY20; + break; + default: + dev_dbg(&dev->dev, "Sony invalid bitcount %u\n", + data->count); + goto out; + } + + scancode = device << 16 | subdevice << 8 | function; + dev_dbg(&dev->dev, "Sony(%u) scancode 0x%05x\n", data->count, + scancode); + rc_keydown(dev, protocol, scancode, 0); + goto finish_state_machine; + } + +out: + dev_dbg(&dev->dev, "Sony decode failed at state %d (%uus %s)\n", + data->state, ev.duration, TO_STR(ev.pulse)); + data->state = STATE_INACTIVE; + return -EINVAL; + +finish_state_machine: + data->state = STATE_INACTIVE; + return 0; +} + +static const struct ir_raw_timings_pl ir_sony_timings = { + .header_pulse = SONY_HEADER_PULSE, + .bit_space = SONY_BIT_SPACE, + .bit_pulse[0] = SONY_BIT_0_PULSE, + .bit_pulse[1] = SONY_BIT_1_PULSE, + .trailer_space = SONY_TRAILER_SPACE + SONY_BIT_SPACE, + .msb_first = 0, +}; + +/** + * ir_sony_encode() - Encode a scancode as a stream of raw events + * + * @protocol: protocol to encode + * @scancode: scancode to encode + * @events: array of raw ir events to write into + * @max: maximum size of @events + * + * Returns: The number of events written. + * -ENOBUFS if there isn't enough space in the array to fit the + * encoding. In this case all @max events will have been written. + */ +static int ir_sony_encode(enum rc_proto protocol, u32 scancode, + struct ir_raw_event *events, unsigned int max) +{ + struct ir_raw_event *e = events; + u32 raw, len; + int ret; + + if (protocol == RC_PROTO_SONY12) { + raw = (scancode & 0x7f) | ((scancode & 0x1f0000) >> 9); + len = 12; + } else if (protocol == RC_PROTO_SONY15) { + raw = (scancode & 0x7f) | ((scancode & 0xff0000) >> 9); + len = 15; + } else { + raw = (scancode & 0x7f) | ((scancode & 0x1f0000) >> 9) | + ((scancode & 0xff00) << 4); + len = 20; + } + + ret = ir_raw_gen_pl(&e, max, &ir_sony_timings, len, raw); + if (ret < 0) + return ret; + + return e - events; +} + +static struct ir_raw_handler sony_handler = { + .protocols = RC_PROTO_BIT_SONY12 | RC_PROTO_BIT_SONY15 | + RC_PROTO_BIT_SONY20, + .decode = ir_sony_decode, + .encode = ir_sony_encode, + .carrier = 40000, + .min_timeout = SONY_TRAILER_SPACE, +}; + +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"); |