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Diffstat (limited to 'drivers/media/rc/img-ir/img-ir-nec.c')
-rw-r--r--drivers/media/rc/img-ir/img-ir-nec.c173
1 files changed, 173 insertions, 0 deletions
diff --git a/drivers/media/rc/img-ir/img-ir-nec.c b/drivers/media/rc/img-ir/img-ir-nec.c
new file mode 100644
index 000000000..c01e30bb6
--- /dev/null
+++ b/drivers/media/rc/img-ir/img-ir-nec.c
@@ -0,0 +1,173 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * ImgTec IR Decoder setup for NEC protocol.
+ *
+ * Copyright 2010-2014 Imagination Technologies Ltd.
+ */
+
+#include "img-ir-hw.h"
+#include <linux/bitrev.h>
+#include <linux/log2.h>
+
+/* Convert NEC data to a scancode */
+static int img_ir_nec_scancode(int len, u64 raw, u64 enabled_protocols,
+ struct img_ir_scancode_req *request)
+{
+ unsigned int addr, addr_inv, data, data_inv;
+ /* a repeat code has no data */
+ if (!len)
+ return IMG_IR_REPEATCODE;
+ if (len != 32)
+ return -EINVAL;
+ /* raw encoding: ddDDaaAA */
+ addr = (raw >> 0) & 0xff;
+ addr_inv = (raw >> 8) & 0xff;
+ data = (raw >> 16) & 0xff;
+ data_inv = (raw >> 24) & 0xff;
+ if ((data_inv ^ data) != 0xff) {
+ /* 32-bit NEC (used by Apple and TiVo remotes) */
+ /* scan encoding: as transmitted, MSBit = first received bit */
+ request->scancode = bitrev8(addr) << 24 |
+ bitrev8(addr_inv) << 16 |
+ bitrev8(data) << 8 |
+ bitrev8(data_inv);
+ request->protocol = RC_PROTO_NEC32;
+ } else if ((addr_inv ^ addr) != 0xff) {
+ /* Extended NEC */
+ /* scan encoding: AAaaDD */
+ request->scancode = addr << 16 |
+ addr_inv << 8 |
+ data;
+ request->protocol = RC_PROTO_NECX;
+ } else {
+ /* Normal NEC */
+ /* scan encoding: AADD */
+ request->scancode = addr << 8 |
+ data;
+ request->protocol = RC_PROTO_NEC;
+ }
+ return IMG_IR_SCANCODE;
+}
+
+/* Convert NEC scancode to NEC data filter */
+static int img_ir_nec_filter(const struct rc_scancode_filter *in,
+ struct img_ir_filter *out, u64 protocols)
+{
+ unsigned int addr, addr_inv, data, data_inv;
+ unsigned int addr_m, addr_inv_m, data_m, data_inv_m;
+
+ data = in->data & 0xff;
+ data_m = in->mask & 0xff;
+
+ protocols &= RC_PROTO_BIT_NEC | RC_PROTO_BIT_NECX | RC_PROTO_BIT_NEC32;
+
+ /*
+ * If only one bit is set, we were requested to do an exact
+ * protocol. This should be the case for wakeup filters; for
+ * normal filters, guess the protocol from the scancode.
+ */
+ if (!is_power_of_2(protocols)) {
+ if ((in->data | in->mask) & 0xff000000)
+ protocols = RC_PROTO_BIT_NEC32;
+ else if ((in->data | in->mask) & 0x00ff0000)
+ protocols = RC_PROTO_BIT_NECX;
+ else
+ protocols = RC_PROTO_BIT_NEC;
+ }
+
+ if (protocols == RC_PROTO_BIT_NEC32) {
+ /* 32-bit NEC (used by Apple and TiVo remotes) */
+ /* scan encoding: as transmitted, MSBit = first received bit */
+ addr = bitrev8(in->data >> 24);
+ addr_m = bitrev8(in->mask >> 24);
+ addr_inv = bitrev8(in->data >> 16);
+ addr_inv_m = bitrev8(in->mask >> 16);
+ data = bitrev8(in->data >> 8);
+ data_m = bitrev8(in->mask >> 8);
+ data_inv = bitrev8(in->data >> 0);
+ data_inv_m = bitrev8(in->mask >> 0);
+ } else if (protocols == RC_PROTO_BIT_NECX) {
+ /* Extended NEC */
+ /* scan encoding AAaaDD */
+ addr = (in->data >> 16) & 0xff;
+ addr_m = (in->mask >> 16) & 0xff;
+ addr_inv = (in->data >> 8) & 0xff;
+ addr_inv_m = (in->mask >> 8) & 0xff;
+ data_inv = data ^ 0xff;
+ data_inv_m = data_m;
+ } else {
+ /* Normal NEC */
+ /* scan encoding: AADD */
+ addr = (in->data >> 8) & 0xff;
+ addr_m = (in->mask >> 8) & 0xff;
+ addr_inv = addr ^ 0xff;
+ addr_inv_m = addr_m;
+ data_inv = data ^ 0xff;
+ data_inv_m = data_m;
+ }
+
+ /* raw encoding: ddDDaaAA */
+ out->data = data_inv << 24 |
+ data << 16 |
+ addr_inv << 8 |
+ addr;
+ out->mask = data_inv_m << 24 |
+ data_m << 16 |
+ addr_inv_m << 8 |
+ addr_m;
+ return 0;
+}
+
+/*
+ * NEC decoder
+ * See also http://www.sbprojects.com/knowledge/ir/nec.php
+ * http://wiki.altium.com/display/ADOH/NEC+Infrared+Transmission+Protocol
+ */
+struct img_ir_decoder img_ir_nec = {
+ .type = RC_PROTO_BIT_NEC | RC_PROTO_BIT_NECX | RC_PROTO_BIT_NEC32,
+ .control = {
+ .decoden = 1,
+ .code_type = IMG_IR_CODETYPE_PULSEDIST,
+ },
+ /* main timings */
+ .unit = 562500, /* 562.5 us */
+ .timings = {
+ /* leader symbol */
+ .ldr = {
+ .pulse = { 16 /* 9ms */ },
+ .space = { 8 /* 4.5ms */ },
+ },
+ /* 0 symbol */
+ .s00 = {
+ .pulse = { 1 /* 562.5 us */ },
+ .space = { 1 /* 562.5 us */ },
+ },
+ /* 1 symbol */
+ .s01 = {
+ .pulse = { 1 /* 562.5 us */ },
+ .space = { 3 /* 1687.5 us */ },
+ },
+ /* free time */
+ .ft = {
+ .minlen = 32,
+ .maxlen = 32,
+ .ft_min = 10, /* 5.625 ms */
+ },
+ },
+ /* repeat codes */
+ .repeat = 108, /* 108 ms */
+ .rtimings = {
+ /* leader symbol */
+ .ldr = {
+ .space = { 4 /* 2.25 ms */ },
+ },
+ /* free time */
+ .ft = {
+ .minlen = 0, /* repeat code has no data */
+ .maxlen = 0,
+ },
+ },
+ /* scancode logic */
+ .scancode = img_ir_nec_scancode,
+ .filter = img_ir_nec_filter,
+};