*/
#include <media/ir-core.h>
+#include <linux/bitrev.h>
#define NEC_NBITS 32
-#define NEC_UNIT 559979 /* ns */
-#define NEC_HEADER_MARK (16 * NEC_UNIT)
-#define NEC_HEADER_SPACE (8 * NEC_UNIT)
-#define NEC_REPEAT_SPACE (4 * NEC_UNIT)
-#define NEC_MARK (NEC_UNIT)
-#define NEC_0_SPACE (NEC_UNIT)
-#define NEC_1_SPACE (3 * NEC_UNIT)
+#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);
enum nec_state {
STATE_INACTIVE,
- STATE_HEADER_MARK,
STATE_HEADER_SPACE,
- STATE_MARK,
- STATE_SPACE,
- STATE_TRAILER_MARK,
+ STATE_BIT_PULSE,
+ STATE_BIT_SPACE,
+ STATE_TRAILER_PULSE,
STATE_TRAILER_SPACE,
};
-struct nec_code {
- u8 address;
- u8 not_address;
- u8 command;
- u8 not_command;
-};
-
struct decoder_data {
struct list_head list;
struct ir_input_dev *ir_dev;
/* State machine control */
enum nec_state state;
- struct nec_code nec_code;
+ 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,
};
-
/**
* ir_nec_decode() - Decode one NEC pulse or space
* @input_dev: the struct input_dev descriptor of the device
- * @ev: event array with type/duration of pulse/space
+ * @duration: duration in ns of pulse/space
*
* This function returns -EINVAL if the pulse violates the state machine
*/
-static int ir_nec_decode(struct input_dev *input_dev,
- struct ir_raw_event *ev)
+static int ir_nec_decode(struct input_dev *input_dev, s64 duration)
{
struct decoder_data *data;
struct ir_input_dev *ir_dev = input_get_drvdata(input_dev);
- int bit, last_bit;
+ int u;
+ u32 scancode;
+ u8 address, not_address, command, not_command;
data = get_decoder_data(ir_dev);
if (!data)
if (!data->enabled)
return 0;
- /* Except for the initial event, what matters is the previous bit */
- bit = (ev->type & IR_PULSE) ? 1 : 0;
-
- last_bit = !bit;
-
- /* Discards spurious space last_bits when inactive */
-
- /* Very long delays are considered as start events */
- if (ev->delta.tv_nsec > NEC_HEADER_MARK + NEC_HEADER_SPACE - NEC_UNIT / 2)
+ if (IS_RESET(duration)) {
data->state = STATE_INACTIVE;
+ return 0;
+ }
- if (ev->type & IR_START_EVENT)
- data->state = STATE_INACTIVE;
+ u = TO_UNITS(duration, NEC_UNIT);
+ if (DURATION(u) == 0)
+ goto out;
+
+ IR_dprintk(2, "NEC decode started at state %d (%i units, %ius)\n",
+ data->state, u, TO_US(duration));
switch (data->state) {
- case STATE_INACTIVE:
- if (!bit) /* PULSE marks the start event */
- return 0;
- data->count = 0;
- data->state = STATE_HEADER_MARK;
- memset (&data->nec_code, 0, sizeof(data->nec_code));
- return 0;
- case STATE_HEADER_MARK:
- if (!last_bit)
- goto err;
- if (ev->delta.tv_nsec < NEC_HEADER_MARK - 6 * NEC_UNIT)
- goto err;
- data->state = STATE_HEADER_SPACE;
+ case STATE_INACTIVE:
+ if (u == NEC_HEADER_PULSE) {
+ data->count = 0;
+ data->state = STATE_HEADER_SPACE;
+ }
return 0;
+
case STATE_HEADER_SPACE:
- if (last_bit)
- goto err;
- if (ev->delta.tv_nsec >= NEC_HEADER_SPACE - NEC_UNIT / 2) {
- data->state = STATE_MARK;
+ if (u == NEC_HEADER_SPACE) {
+ data->state = STATE_BIT_PULSE;
return 0;
- }
-
- if (ev->delta.tv_nsec >= NEC_REPEAT_SPACE - NEC_UNIT / 2) {
+ } else if (u == NEC_REPEAT_SPACE) {
ir_repeat(input_dev);
IR_dprintk(1, "Repeat last key\n");
- data->state = STATE_TRAILER_MARK;
+ data->state = STATE_TRAILER_PULSE;
return 0;
}
- goto err;
- case STATE_MARK:
- if (!last_bit)
- goto err;
- if ((ev->delta.tv_nsec > NEC_MARK + NEC_UNIT / 2) ||
- (ev->delta.tv_nsec < NEC_MARK - NEC_UNIT / 2))
- goto err;
- data->state = STATE_SPACE;
- return 0;
- case STATE_SPACE:
- if (last_bit)
- goto err;
-
- if ((ev->delta.tv_nsec >= NEC_0_SPACE - NEC_UNIT / 2) &&
- (ev->delta.tv_nsec < NEC_0_SPACE + NEC_UNIT / 2))
- bit = 0;
- else if ((ev->delta.tv_nsec >= NEC_1_SPACE - NEC_UNIT / 2) &&
- (ev->delta.tv_nsec < NEC_1_SPACE + NEC_UNIT / 2))
- bit = 1;
- else {
- IR_dprintk(1, "Decode failed at %d-th bit (%s) @%luus\n",
- data->count,
- last_bit ? "pulse" : "space",
- (ev->delta.tv_nsec + 500) / 1000);
-
- goto err2;
+ break;
+
+ case STATE_BIT_PULSE:
+ if (u == NEC_BIT_PULSE) {
+ data->state = STATE_BIT_SPACE;
+ return 0;
+ }
+ break;
+
+ case STATE_BIT_SPACE:
+ if (u != NEC_BIT_0_SPACE && u != NEC_BIT_1_SPACE)
+ break;
+
+ data->nec_bits <<= 1;
+ if (u == NEC_BIT_1_SPACE)
+ data->nec_bits |= 1;
+ data->count++;
+
+ if (data->count != NEC_NBITS) {
+ data->state = STATE_BIT_PULSE;
+ return 0;
+ }
+
+ 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);
+
+ if ((command ^ not_command) != 0xff) {
+ IR_dprintk(1, "NEC checksum error: received 0x%08x\n",
+ data->nec_bits);
+ break;
}
- /* Ok, we've got a valid bit. proccess it */
- if (bit) {
- int shift = data->count;
-
- /*
- * NEC transmit bytes on this temporal order:
- * address | not address | command | not command
- */
- if (shift < 8) {
- data->nec_code.address |= 1 << shift;
- } else if (shift < 16) {
- data->nec_code.not_address |= 1 << (shift - 8);
- } else if (shift < 24) {
- data->nec_code.command |= 1 << (shift - 16);
- } else {
- data->nec_code.not_command |= 1 << (shift - 24);
- }
+ 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);
}
- if (++data->count == NEC_NBITS) {
- u32 scancode;
- /*
- * Fixme: may need to accept Extended NEC protocol?
- */
- if ((data->nec_code.command ^ data->nec_code.not_command) != 0xff)
- goto checksum_err;
-
- if ((data->nec_code.address ^ data->nec_code.not_address) != 0xff) {
- /* Extended NEC */
- scancode = data->nec_code.address << 16 |
- data->nec_code.not_address << 8 |
- data->nec_code.command;
- IR_dprintk(1, "NEC scancode 0x%06x\n", scancode);
- } else {
- /* normal NEC */
- scancode = data->nec_code.address << 8 |
- data->nec_code.command;
- IR_dprintk(1, "NEC scancode 0x%04x\n", scancode);
- }
- ir_keydown(input_dev, scancode, 0);
-
- data->state = STATE_TRAILER_MARK;
- } else
- data->state = STATE_MARK;
- return 0;
- case STATE_TRAILER_MARK:
- if (!last_bit)
- goto err;
- data->state = STATE_TRAILER_SPACE;
+
+ ir_keydown(input_dev, scancode, 0);
+ data->state = STATE_TRAILER_PULSE;
return 0;
+
+ case STATE_TRAILER_PULSE:
+ if (u > 0) {
+ data->state = STATE_TRAILER_SPACE;
+ return 0;
+ }
+ break;
+
case STATE_TRAILER_SPACE:
- if (last_bit)
- goto err;
- data->state = STATE_INACTIVE;
- return 0;
- }
+ if (u < 0) {
+ data->state = STATE_INACTIVE;
+ return 0;
+ }
-err:
- IR_dprintk(1, "NEC decoded failed at state %d (%s) @ %luus\n",
- data->state,
- bit ? "pulse" : "space",
- (ev->delta.tv_nsec + 500) / 1000);
-err2:
- data->state = STATE_INACTIVE;
- return -EINVAL;
+ break;
+ }
-checksum_err:
+out:
+ IR_dprintk(1, "NEC decode failed at state %d (%i units, %ius)\n",
+ data->state, u, TO_US(duration));
data->state = STATE_INACTIVE;
- IR_dprintk(1, "NEC checksum error: received 0x%02x%02x%02x%02x\n",
- data->nec_code.address,
- data->nec_code.not_address,
- data->nec_code.command,
- data->nec_code.not_command);
return -EINVAL;
}
projects / cascardo / linux.git / blobdiff