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-rw-r--r--drivers/media/common/ir-functions.c272
1 files changed, 272 insertions, 0 deletions
diff --git a/drivers/media/common/ir-functions.c b/drivers/media/common/ir-functions.c
new file mode 100644
index 000000000000..397cff8b345b
--- /dev/null
+++ b/drivers/media/common/ir-functions.c
@@ -0,0 +1,272 @@
+/*
+ *
+ * some common structs and functions to handle infrared remotes via
+ * input layer ...
+ *
+ * (c) 2003 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/string.h>
+#include <media/ir-common.h>
+
+/* -------------------------------------------------------------------------- */
+
+MODULE_AUTHOR("Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]");
+MODULE_LICENSE("GPL");
+
+static int repeat = 1;
+module_param(repeat, int, 0444);
+MODULE_PARM_DESC(repeat,"auto-repeat for IR keys (default: on)");
+
+static int debug = 0; /* debug level (0,1,2) */
+module_param(debug, int, 0644);
+
+#define dprintk(level, fmt, arg...) if (debug >= level) \
+ printk(KERN_DEBUG fmt , ## arg)
+
+/* -------------------------------------------------------------------------- */
+
+static void ir_input_key_event(struct input_dev *dev, struct ir_input_state *ir)
+{
+ if (KEY_RESERVED == ir->keycode) {
+ printk(KERN_INFO "%s: unknown key: key=0x%02x raw=0x%02x down=%d\n",
+ dev->name,ir->ir_key,ir->ir_raw,ir->keypressed);
+ return;
+ }
+ dprintk(1,"%s: key event code=%d down=%d\n",
+ dev->name,ir->keycode,ir->keypressed);
+ input_report_key(dev,ir->keycode,ir->keypressed);
+ input_sync(dev);
+}
+
+/* -------------------------------------------------------------------------- */
+
+void ir_input_init(struct input_dev *dev, struct ir_input_state *ir,
+ int ir_type, IR_KEYTAB_TYPE *ir_codes)
+{
+ int i;
+
+ ir->ir_type = ir_type;
+ if (ir_codes)
+ memcpy(ir->ir_codes, ir_codes, sizeof(ir->ir_codes));
+
+
+ dev->keycode = ir->ir_codes;
+ dev->keycodesize = sizeof(IR_KEYTAB_TYPE);
+ dev->keycodemax = IR_KEYTAB_SIZE;
+ for (i = 0; i < IR_KEYTAB_SIZE; i++)
+ set_bit(ir->ir_codes[i], dev->keybit);
+ clear_bit(0, dev->keybit);
+
+ set_bit(EV_KEY, dev->evbit);
+ if (repeat)
+ set_bit(EV_REP, dev->evbit);
+}
+
+void ir_input_nokey(struct input_dev *dev, struct ir_input_state *ir)
+{
+ if (ir->keypressed) {
+ ir->keypressed = 0;
+ ir_input_key_event(dev,ir);
+ }
+}
+
+void ir_input_keydown(struct input_dev *dev, struct ir_input_state *ir,
+ u32 ir_key, u32 ir_raw)
+{
+ u32 keycode = IR_KEYCODE(ir->ir_codes, ir_key);
+
+ if (ir->keypressed && ir->keycode != keycode) {
+ ir->keypressed = 0;
+ ir_input_key_event(dev,ir);
+ }
+ if (!ir->keypressed) {
+ ir->ir_key = ir_key;
+ ir->ir_raw = ir_raw;
+ ir->keycode = keycode;
+ ir->keypressed = 1;
+ ir_input_key_event(dev,ir);
+ }
+}
+
+/* -------------------------------------------------------------------------- */
+
+u32 ir_extract_bits(u32 data, u32 mask)
+{
+ int mbit, vbit;
+ u32 value;
+
+ value = 0;
+ vbit = 0;
+ for (mbit = 0; mbit < 32; mbit++) {
+ if (!(mask & ((u32)1 << mbit)))
+ continue;
+ if (data & ((u32)1 << mbit))
+ value |= (1 << vbit);
+ vbit++;
+ }
+ return value;
+}
+
+static int inline getbit(u32 *samples, int bit)
+{
+ return (samples[bit/32] & (1 << (31-(bit%32)))) ? 1 : 0;
+}
+
+/* sump raw samples for visual debugging ;) */
+int ir_dump_samples(u32 *samples, int count)
+{
+ int i, bit, start;
+
+ printk(KERN_DEBUG "ir samples: ");
+ start = 0;
+ for (i = 0; i < count * 32; i++) {
+ bit = getbit(samples,i);
+ if (bit)
+ start = 1;
+ if (0 == start)
+ continue;
+ printk("%s", bit ? "#" : "_");
+ }
+ printk("\n");
+ return 0;
+}
+
+/* decode raw samples, pulse distance coding used by NEC remotes */
+int ir_decode_pulsedistance(u32 *samples, int count, int low, int high)
+{
+ int i,last,bit,len;
+ u32 curBit;
+ u32 value;
+
+ /* find start burst */
+ for (i = len = 0; i < count * 32; i++) {
+ bit = getbit(samples,i);
+ if (bit) {
+ len++;
+ } else {
+ if (len >= 29)
+ break;
+ len = 0;
+ }
+ }
+
+ /* start burst to short */
+ if (len < 29)
+ return 0xffffffff;
+
+ /* find start silence */
+ for (len = 0; i < count * 32; i++) {
+ bit = getbit(samples,i);
+ if (bit) {
+ break;
+ } else {
+ len++;
+ }
+ }
+
+ /* silence to short */
+ if (len < 7)
+ return 0xffffffff;
+
+ /* go decoding */
+ len = 0;
+ last = 1;
+ value = 0; curBit = 1;
+ for (; i < count * 32; i++) {
+ bit = getbit(samples,i);
+ if (last) {
+ if(bit) {
+ continue;
+ } else {
+ len = 1;
+ }
+ } else {
+ if (bit) {
+ if (len > (low + high) /2)
+ value |= curBit;
+ curBit <<= 1;
+ if (curBit == 1)
+ break;
+ } else {
+ len++;
+ }
+ }
+ last = bit;
+ }
+
+ return value;
+}
+
+/* decode raw samples, biphase coding, used by rc5 for example */
+int ir_decode_biphase(u32 *samples, int count, int low, int high)
+{
+ int i,last,bit,len,flips;
+ u32 value;
+
+ /* find start bit (1) */
+ for (i = 0; i < 32; i++) {
+ bit = getbit(samples,i);
+ if (bit)
+ break;
+ }
+
+ /* go decoding */
+ len = 0;
+ flips = 0;
+ value = 1;
+ for (; i < count * 32; i++) {
+ if (len > high)
+ break;
+ if (flips > 1)
+ break;
+ last = bit;
+ bit = getbit(samples,i);
+ if (last == bit) {
+ len++;
+ continue;
+ }
+ if (len < low) {
+ len++;
+ flips++;
+ continue;
+ }
+ value <<= 1;
+ value |= bit;
+ flips = 0;
+ len = 1;
+ }
+ return value;
+}
+
+EXPORT_SYMBOL_GPL(ir_input_init);
+EXPORT_SYMBOL_GPL(ir_input_nokey);
+EXPORT_SYMBOL_GPL(ir_input_keydown);
+
+EXPORT_SYMBOL_GPL(ir_extract_bits);
+EXPORT_SYMBOL_GPL(ir_dump_samples);
+EXPORT_SYMBOL_GPL(ir_decode_biphase);
+EXPORT_SYMBOL_GPL(ir_decode_pulsedistance);
+
+/*
+ * Local variables:
+ * c-basic-offset: 8
+ * End:
+ */
+