*/
#include <media/ir-core.h>
+#include <linux/bitrev.h>
-/* Start time: 4.5 ms + 560 us of the next pulse */
-#define MIN_START_TIME (3900000 + 560000)
-#define MAX_START_TIME (5100000 + 560000)
-
-/* Bit 1 time: 2.25ms us */
-#define MIN_BIT1_TIME 2050000
-#define MAX_BIT1_TIME 2450000
-
-/* Bit 0 time: 1.12ms us */
-#define MIN_BIT0_TIME 920000
-#define MAX_BIT0_TIME 1320000
-
-/* Total IR code is 110 ms, including the 9 ms for the start pulse */
-#define MAX_NEC_TIME 4000000
-
-/* Total IR code is 110 ms, including the 9 ms for the start pulse */
-#define MIN_REPEAT_TIME 99000000
-#define MAX_REPEAT_TIME 112000000
-
-/* Repeat time: 2.25ms us */
-#define MIN_REPEAT_START_TIME 2050000
-#define MAX_REPEAT_START_TIME 3000000
-
-#define REPEAT_TIME 240 /* ms */
+#define NEC_NBITS 32
+#define NEC_UNIT 562500 /* ns */
+#define NEC_HEADER_PULSE PULSE(16)
+#define NEC_HEADER_SPACE SPACE(8)
+#define NEC_REPEAT_SPACE SPACE(4)
+#define NEC_BIT_PULSE PULSE(1)
+#define NEC_BIT_0_SPACE SPACE(1)
+#define NEC_BIT_1_SPACE SPACE(3)
/* Used to register nec_decoder clients */
static LIST_HEAD(decoder_list);
-static spinlock_t decoder_lock;
+static DEFINE_SPINLOCK(decoder_lock);
+
+enum nec_state {
+ STATE_INACTIVE,
+ STATE_HEADER_SPACE,
+ STATE_BIT_PULSE,
+ STATE_BIT_SPACE,
+ STATE_TRAILER_PULSE,
+ STATE_TRAILER_SPACE,
+};
struct decoder_data {
struct list_head list;
struct ir_input_dev *ir_dev;
int enabled:1;
+
+ /* State machine control */
+ enum nec_state state;
+ u32 nec_bits;
+ unsigned count;
};
*
* Returns the struct decoder_data that corresponds to a device
*/
-
static struct decoder_data *get_decoder_data(struct ir_input_dev *ir_dev)
{
struct decoder_data *data = NULL;
.attrs = decoder_attributes,
};
-
-/** is_repeat - Check if it is a NEC repeat event
+/**
+ * ir_nec_decode() - Decode one NEC pulse or space
* @input_dev: the struct input_dev descriptor of the device
- * @pos: the position of the first event
- * @len: the length of the buffer
+ * @duration: duration in ns of pulse/space
+ *
+ * This function returns -EINVAL if the pulse violates the state machine
*/
-static int is_repeat(struct ir_raw_event *evs, int len, int pos)
+static int ir_nec_decode(struct input_dev *input_dev, s64 duration)
{
- if ((evs[pos].delta.tv_nsec < MIN_REPEAT_START_TIME) ||
- (evs[pos].delta.tv_nsec > MAX_REPEAT_START_TIME))
- return 0;
+ struct decoder_data *data;
+ struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
+ int u;
+ u32 scancode;
+ u8 address, not_address, command, not_command;
- if (++pos >= len)
- return 0;
+ data = get_decoder_data(ir_dev);
+ if (!data)
+ return -EINVAL;
- if ((evs[pos].delta.tv_nsec < MIN_REPEAT_TIME) ||
- (evs[pos].delta.tv_nsec > MAX_REPEAT_TIME))
+ if (!data->enabled)
return 0;
- return 1;
-}
+ if (IS_RESET(duration)) {
+ data->state = STATE_INACTIVE;
+ return 0;
+ }
-/**
- * __ir_nec_decode() - Decode one NEC pulsecode
- * @input_dev: the struct input_dev descriptor of the device
- * @evs: event array with type/duration of pulse/space
- * @len: length of the array
- * @pos: position to start seeking for a code
- * This function returns -EINVAL if no pulse got decoded,
- * 0 if buffer is empty and 1 if one keycode were handled.
- */
-static int __ir_nec_decode(struct input_dev *input_dev,
- struct ir_raw_event *evs,
- int len, int *pos)
-{
- struct ir_input_dev *ir = input_get_drvdata(input_dev);
- int count = -1;
- int ircode = 0, not_code = 0;
-
- /* Be sure that the first event is an start one and is a pulse */
- for (; *pos < len; (*pos)++) {
- /* Very long delays are considered as start events */
- if (evs[*pos].delta.tv_nsec > MAX_NEC_TIME)
- break;
- if (evs[*pos].type & IR_START_EVENT)
- break;
- IR_dprintk(1, "%luus: Spurious NEC %s\n",
- (evs[*pos].delta.tv_nsec + 500) / 1000,
- (evs[*pos].type & IR_SPACE) ? "space" : "pulse");
+ u = TO_UNITS(duration, NEC_UNIT);
+ if (DURATION(u) == 0)
+ goto out;
- }
- if (*pos >= len)
- return 0;
+ IR_dprintk(2, "NEC decode started at state %d (%i units, %ius)\n",
+ data->state, u, TO_US(duration));
- (*pos)++; /* First event doesn't contain data */
+ switch (data->state) {
- if (evs[*pos].type != IR_PULSE)
- goto err;
+ case STATE_INACTIVE:
+ if (u == NEC_HEADER_PULSE) {
+ data->count = 0;
+ data->state = STATE_HEADER_SPACE;
+ }
+ return 0;
- /* Check if it is a NEC repeat event */
- if (is_repeat(evs, len, *pos)) {
- *pos += 2;
- if (ir->keypressed) {
+ case STATE_HEADER_SPACE:
+ if (u == NEC_HEADER_SPACE) {
+ data->state = STATE_BIT_PULSE;
+ return 0;
+ } else if (u == NEC_REPEAT_SPACE) {
ir_repeat(input_dev);
- IR_dprintk(1, "NEC repeat event\n");
- return 1;
- } else {
- IR_dprintk(1, "missing NEC repeat event\n");
+ IR_dprintk(1, "Repeat last key\n");
+ data->state = STATE_TRAILER_PULSE;
return 0;
}
- }
+ break;
- /* First space should have 4.5 ms otherwise is not NEC protocol */
- if ((evs[*pos].delta.tv_nsec < MIN_START_TIME) ||
- (evs[*pos].delta.tv_nsec > MAX_START_TIME))
- goto err;
-
- count = 0;
- for ((*pos)++; *pos < len; (*pos)++) {
- int bit;
- if ((evs[*pos].delta.tv_nsec > MIN_BIT1_TIME) &&
- (evs[*pos].delta.tv_nsec < MAX_BIT1_TIME))
- bit = 1;
- else if ((evs[*pos].delta.tv_nsec > MIN_BIT0_TIME) &&
- (evs[*pos].delta.tv_nsec < MAX_BIT0_TIME))
- bit = 0;
- else
- goto err;
-
- if (bit) {
- int shift = count;
- /* Address first, then command */
- if (shift < 8) {
- shift += 8;
- ircode |= 1 << shift;
- } else if (shift < 16) {
- not_code |= 1 << shift;
- } else if (shift < 24) {
- shift -= 16;
- ircode |= 1 << shift;
- } else {
- shift -= 24;
- not_code |= 1 << shift;
- }
+ case STATE_BIT_PULSE:
+ if (u == NEC_BIT_PULSE) {
+ data->state = STATE_BIT_SPACE;
+ return 0;
}
- if (++count == 32)
+ break;
+
+ case STATE_BIT_SPACE:
+ if (u != NEC_BIT_0_SPACE && u != NEC_BIT_1_SPACE)
break;
- }
- (*pos)++;
-
- /*
- * Fixme: may need to accept Extended NEC protocol?
- */
- if ((ircode & ~not_code) != ircode) {
- IR_dprintk(1, "NEC checksum error: code 0x%04x, not-code 0x%04x\n",
- ircode, not_code);
- return -EINVAL;
- }
- IR_dprintk(1, "NEC scancode 0x%04x\n", ircode);
- ir_keydown(input_dev, ircode, 0);
+ data->nec_bits <<= 1;
+ if (u == NEC_BIT_1_SPACE)
+ data->nec_bits |= 1;
+ data->count++;
- return 1;
-err:
- IR_dprintk(1, "NEC decoded failed at bit %d (%s) while decoding %luus time\n",
- count,
- (evs[*pos].type & IR_SPACE) ? "space" : "pulse",
- (evs[*pos].delta.tv_nsec + 500) / 1000);
+ if (data->count != NEC_NBITS) {
+ data->state = STATE_BIT_PULSE;
+ return 0;
+ }
- return -EINVAL;
-}
+ address = bitrev8((data->nec_bits >> 24) & 0xff);
+ not_address = bitrev8((data->nec_bits >> 16) & 0xff);
+ command = bitrev8((data->nec_bits >> 8) & 0xff);
+ not_command = bitrev8((data->nec_bits >> 0) & 0xff);
-/**
- * __ir_nec_decode() - Decodes all NEC pulsecodes on a given array
- * @input_dev: the struct input_dev descriptor of the device
- * @evs: event array with type/duration of pulse/space
- * @len: length of the array
- * This function returns the number of decoded pulses
- */
-static int ir_nec_decode(struct input_dev *input_dev,
- struct ir_raw_event *evs,
- int len)
-{
- struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
- struct decoder_data *data;
- int pos = 0;
- int rc = 0;
+ if ((command ^ not_command) != 0xff) {
+ IR_dprintk(1, "NEC checksum error: received 0x%08x\n",
+ data->nec_bits);
+ break;
+ }
- data = get_decoder_data(ir_dev);
- if (!data || !data->enabled)
+ if ((address ^ not_address) != 0xff) {
+ /* Extended NEC */
+ scancode = address << 16 |
+ not_address << 8 |
+ command;
+ IR_dprintk(1, "NEC (Ext) scancode 0x%06x\n", scancode);
+ } else {
+ /* normal NEC */
+ scancode = address << 8 | command;
+ IR_dprintk(1, "NEC scancode 0x%04x\n", scancode);
+ }
+
+ ir_keydown(input_dev, scancode, 0);
+ data->state = STATE_TRAILER_PULSE;
return 0;
- while (pos < len) {
- if (__ir_nec_decode(input_dev, evs, len, &pos) > 0)
- rc++;
+ case STATE_TRAILER_PULSE:
+ if (u > 0) {
+ data->state = STATE_TRAILER_SPACE;
+ return 0;
+ }
+ break;
+
+ case STATE_TRAILER_SPACE:
+ if (u < 0) {
+ data->state = STATE_INACTIVE;
+ return 0;
+ }
+
+ break;
}
- return rc;
+
+out:
+ IR_dprintk(1, "NEC decode failed at state %d (%i units, %ius)\n",
+ data->state, u, TO_US(duration));
+ data->state = STATE_INACTIVE;
+ return -EINVAL;
}
static int ir_nec_register(struct input_dev *input_dev)
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff