[PATCH v5 3/3] bpf: add selftest for lirc_mode2 type program

From: Sean Young
Date: Sun May 27 2018 - 07:24:25 EST


This is simple test over rc-loopback.

Acked-by: Yonghong Song <yhs@xxxxxx>
Signed-off-by: Sean Young <sean@xxxxxxxx>
---
tools/bpf/bpftool/prog.c | 1 +
tools/include/uapi/linux/bpf.h | 53 ++++-
tools/include/uapi/linux/lirc.h | 217 ++++++++++++++++++
tools/lib/bpf/libbpf.c | 1 +
tools/testing/selftests/bpf/.gitignore | 1 +
tools/testing/selftests/bpf/Makefile | 7 +-
tools/testing/selftests/bpf/bpf_helpers.h | 5 +
.../testing/selftests/bpf/test_lirc_mode2.sh | 28 +++
.../selftests/bpf/test_lirc_mode2_kern.c | 23 ++
.../selftests/bpf/test_lirc_mode2_user.c | 149 ++++++++++++
10 files changed, 481 insertions(+), 4 deletions(-)
create mode 100644 tools/include/uapi/linux/lirc.h
create mode 100755 tools/testing/selftests/bpf/test_lirc_mode2.sh
create mode 100644 tools/testing/selftests/bpf/test_lirc_mode2_kern.c
create mode 100644 tools/testing/selftests/bpf/test_lirc_mode2_user.c

diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c
index 39b88e760367..a4f435203fef 100644
--- a/tools/bpf/bpftool/prog.c
+++ b/tools/bpf/bpftool/prog.c
@@ -71,6 +71,7 @@ static const char * const prog_type_name[] = {
[BPF_PROG_TYPE_SK_MSG] = "sk_msg",
[BPF_PROG_TYPE_RAW_TRACEPOINT] = "raw_tracepoint",
[BPF_PROG_TYPE_CGROUP_SOCK_ADDR] = "cgroup_sock_addr",
+ [BPF_PROG_TYPE_LIRC_MODE2] = "lirc_mode2",
};

static void print_boot_time(__u64 nsecs, char *buf, unsigned int size)
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 9b8c6e310e9a..4636c596096d 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -143,6 +143,7 @@ enum bpf_prog_type {
BPF_PROG_TYPE_RAW_TRACEPOINT,
BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
BPF_PROG_TYPE_LWT_SEG6LOCAL,
+ BPF_PROG_TYPE_LIRC_MODE2,
};

enum bpf_attach_type {
@@ -160,6 +161,7 @@ enum bpf_attach_type {
BPF_CGROUP_INET6_CONNECT,
BPF_CGROUP_INET4_POST_BIND,
BPF_CGROUP_INET6_POST_BIND,
+ BPF_LIRC_MODE2,
__MAX_BPF_ATTACH_TYPE
};

@@ -2004,6 +2006,53 @@ union bpf_attr {
* direct packet access.
* Return
* 0 on success, or a negative error in case of failure.
+ *
+ * int bpf_rc_keydown(void *ctx, u32 protocol, u64 scancode, u32 toggle)
+ * Description
+ * This helper is used in programs implementing IR decoding, to
+ * report a successfully decoded key press with *scancode*,
+ * *toggle* value in the given *protocol*. The scancode will be
+ * translated to a keycode using the rc keymap, and reported as
+ * an input key down event. After a period a key up event is
+ * generated. This period can be extended by calling either
+ * **bpf_rc_keydown** () again with the same values, or calling
+ * **bpf_rc_repeat** ().
+ *
+ * Some protocols include a toggle bit, in case the button was
+ * released and pressed again between consecutive scancodes.
+ *
+ * The *ctx* should point to the lirc sample as passed into
+ * the program.
+ *
+ * The *protocol* is the decoded protocol number (see
+ * **enum rc_proto** for some predefined values).
+ *
+ * This helper is only available is the kernel was compiled with
+ * the **CONFIG_BPF_LIRC_MODE2** configuration option set to
+ * "**y**".
+ *
+ * Return
+ * 0
+ *
+ * int bpf_rc_repeat(void *ctx)
+ * Description
+ * This helper is used in programs implementing IR decoding, to
+ * report a successfully decoded repeat key message. This delays
+ * the generation of a key up event for previously generated
+ * key down event.
+ *
+ * Some IR protocols like NEC have a special IR message for
+ * repeating last button, for when a button is held down.
+ *
+ * The *ctx* should point to the lirc sample as passed into
+ * the program.
+ *
+ * This helper is only available is the kernel was compiled with
+ * the **CONFIG_BPF_LIRC_MODE2** configuration option set to
+ * "**y**".
+ *
+ * Return
+ * 0
*/
#define __BPF_FUNC_MAPPER(FN) \
FN(unspec), \
@@ -2082,7 +2131,9 @@ union bpf_attr {
FN(lwt_push_encap), \
FN(lwt_seg6_store_bytes), \
FN(lwt_seg6_adjust_srh), \
- FN(lwt_seg6_action),
+ FN(lwt_seg6_action), \
+ FN(rc_repeat), \
+ FN(rc_keydown),

/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
diff --git a/tools/include/uapi/linux/lirc.h b/tools/include/uapi/linux/lirc.h
new file mode 100644
index 000000000000..f189931042a7
--- /dev/null
+++ b/tools/include/uapi/linux/lirc.h
@@ -0,0 +1,217 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * lirc.h - linux infrared remote control header file
+ * last modified 2010/07/13 by Jarod Wilson
+ */
+
+#ifndef _LINUX_LIRC_H
+#define _LINUX_LIRC_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+#define PULSE_BIT 0x01000000
+#define PULSE_MASK 0x00FFFFFF
+
+#define LIRC_MODE2_SPACE 0x00000000
+#define LIRC_MODE2_PULSE 0x01000000
+#define LIRC_MODE2_FREQUENCY 0x02000000
+#define LIRC_MODE2_TIMEOUT 0x03000000
+
+#define LIRC_VALUE_MASK 0x00FFFFFF
+#define LIRC_MODE2_MASK 0xFF000000
+
+#define LIRC_SPACE(val) (((val)&LIRC_VALUE_MASK) | LIRC_MODE2_SPACE)
+#define LIRC_PULSE(val) (((val)&LIRC_VALUE_MASK) | LIRC_MODE2_PULSE)
+#define LIRC_FREQUENCY(val) (((val)&LIRC_VALUE_MASK) | LIRC_MODE2_FREQUENCY)
+#define LIRC_TIMEOUT(val) (((val)&LIRC_VALUE_MASK) | LIRC_MODE2_TIMEOUT)
+
+#define LIRC_VALUE(val) ((val)&LIRC_VALUE_MASK)
+#define LIRC_MODE2(val) ((val)&LIRC_MODE2_MASK)
+
+#define LIRC_IS_SPACE(val) (LIRC_MODE2(val) == LIRC_MODE2_SPACE)
+#define LIRC_IS_PULSE(val) (LIRC_MODE2(val) == LIRC_MODE2_PULSE)
+#define LIRC_IS_FREQUENCY(val) (LIRC_MODE2(val) == LIRC_MODE2_FREQUENCY)
+#define LIRC_IS_TIMEOUT(val) (LIRC_MODE2(val) == LIRC_MODE2_TIMEOUT)
+
+/* used heavily by lirc userspace */
+#define lirc_t int
+
+/*** lirc compatible hardware features ***/
+
+#define LIRC_MODE2SEND(x) (x)
+#define LIRC_SEND2MODE(x) (x)
+#define LIRC_MODE2REC(x) ((x) << 16)
+#define LIRC_REC2MODE(x) ((x) >> 16)
+
+#define LIRC_MODE_RAW 0x00000001
+#define LIRC_MODE_PULSE 0x00000002
+#define LIRC_MODE_MODE2 0x00000004
+#define LIRC_MODE_SCANCODE 0x00000008
+#define LIRC_MODE_LIRCCODE 0x00000010
+
+
+#define LIRC_CAN_SEND_RAW LIRC_MODE2SEND(LIRC_MODE_RAW)
+#define LIRC_CAN_SEND_PULSE LIRC_MODE2SEND(LIRC_MODE_PULSE)
+#define LIRC_CAN_SEND_MODE2 LIRC_MODE2SEND(LIRC_MODE_MODE2)
+#define LIRC_CAN_SEND_LIRCCODE LIRC_MODE2SEND(LIRC_MODE_LIRCCODE)
+
+#define LIRC_CAN_SEND_MASK 0x0000003f
+
+#define LIRC_CAN_SET_SEND_CARRIER 0x00000100
+#define LIRC_CAN_SET_SEND_DUTY_CYCLE 0x00000200
+#define LIRC_CAN_SET_TRANSMITTER_MASK 0x00000400
+
+#define LIRC_CAN_REC_RAW LIRC_MODE2REC(LIRC_MODE_RAW)
+#define LIRC_CAN_REC_PULSE LIRC_MODE2REC(LIRC_MODE_PULSE)
+#define LIRC_CAN_REC_MODE2 LIRC_MODE2REC(LIRC_MODE_MODE2)
+#define LIRC_CAN_REC_SCANCODE LIRC_MODE2REC(LIRC_MODE_SCANCODE)
+#define LIRC_CAN_REC_LIRCCODE LIRC_MODE2REC(LIRC_MODE_LIRCCODE)
+
+#define LIRC_CAN_REC_MASK LIRC_MODE2REC(LIRC_CAN_SEND_MASK)
+
+#define LIRC_CAN_SET_REC_CARRIER (LIRC_CAN_SET_SEND_CARRIER << 16)
+#define LIRC_CAN_SET_REC_DUTY_CYCLE (LIRC_CAN_SET_SEND_DUTY_CYCLE << 16)
+
+#define LIRC_CAN_SET_REC_DUTY_CYCLE_RANGE 0x40000000
+#define LIRC_CAN_SET_REC_CARRIER_RANGE 0x80000000
+#define LIRC_CAN_GET_REC_RESOLUTION 0x20000000
+#define LIRC_CAN_SET_REC_TIMEOUT 0x10000000
+#define LIRC_CAN_SET_REC_FILTER 0x08000000
+
+#define LIRC_CAN_MEASURE_CARRIER 0x02000000
+#define LIRC_CAN_USE_WIDEBAND_RECEIVER 0x04000000
+
+#define LIRC_CAN_SEND(x) ((x)&LIRC_CAN_SEND_MASK)
+#define LIRC_CAN_REC(x) ((x)&LIRC_CAN_REC_MASK)
+
+#define LIRC_CAN_NOTIFY_DECODE 0x01000000
+
+/*** IOCTL commands for lirc driver ***/
+
+#define LIRC_GET_FEATURES _IOR('i', 0x00000000, __u32)
+
+#define LIRC_GET_SEND_MODE _IOR('i', 0x00000001, __u32)
+#define LIRC_GET_REC_MODE _IOR('i', 0x00000002, __u32)
+#define LIRC_GET_REC_RESOLUTION _IOR('i', 0x00000007, __u32)
+
+#define LIRC_GET_MIN_TIMEOUT _IOR('i', 0x00000008, __u32)
+#define LIRC_GET_MAX_TIMEOUT _IOR('i', 0x00000009, __u32)
+
+/* code length in bits, currently only for LIRC_MODE_LIRCCODE */
+#define LIRC_GET_LENGTH _IOR('i', 0x0000000f, __u32)
+
+#define LIRC_SET_SEND_MODE _IOW('i', 0x00000011, __u32)
+#define LIRC_SET_REC_MODE _IOW('i', 0x00000012, __u32)
+/* Note: these can reset the according pulse_width */
+#define LIRC_SET_SEND_CARRIER _IOW('i', 0x00000013, __u32)
+#define LIRC_SET_REC_CARRIER _IOW('i', 0x00000014, __u32)
+#define LIRC_SET_SEND_DUTY_CYCLE _IOW('i', 0x00000015, __u32)
+#define LIRC_SET_TRANSMITTER_MASK _IOW('i', 0x00000017, __u32)
+
+/*
+ * when a timeout != 0 is set the driver will send a
+ * LIRC_MODE2_TIMEOUT data packet, otherwise LIRC_MODE2_TIMEOUT is
+ * never sent, timeout is disabled by default
+ */
+#define LIRC_SET_REC_TIMEOUT _IOW('i', 0x00000018, __u32)
+
+/* 1 enables, 0 disables timeout reports in MODE2 */
+#define LIRC_SET_REC_TIMEOUT_REPORTS _IOW('i', 0x00000019, __u32)
+
+/*
+ * if enabled from the next key press on the driver will send
+ * LIRC_MODE2_FREQUENCY packets
+ */
+#define LIRC_SET_MEASURE_CARRIER_MODE _IOW('i', 0x0000001d, __u32)
+
+/*
+ * to set a range use LIRC_SET_REC_CARRIER_RANGE with the
+ * lower bound first and later LIRC_SET_REC_CARRIER with the upper bound
+ */
+#define LIRC_SET_REC_CARRIER_RANGE _IOW('i', 0x0000001f, __u32)
+
+#define LIRC_SET_WIDEBAND_RECEIVER _IOW('i', 0x00000023, __u32)
+
+/*
+ * struct lirc_scancode - decoded scancode with protocol for use with
+ * LIRC_MODE_SCANCODE
+ *
+ * @timestamp: Timestamp in nanoseconds using CLOCK_MONOTONIC when IR
+ * was decoded.
+ * @flags: should be 0 for transmit. When receiving scancodes,
+ * LIRC_SCANCODE_FLAG_TOGGLE or LIRC_SCANCODE_FLAG_REPEAT can be set
+ * depending on the protocol
+ * @rc_proto: see enum rc_proto
+ * @keycode: the translated keycode. Set to 0 for transmit.
+ * @scancode: the scancode received or to be sent
+ */
+struct lirc_scancode {
+ __u64 timestamp;
+ __u16 flags;
+ __u16 rc_proto;
+ __u32 keycode;
+ __u64 scancode;
+};
+
+/* Set if the toggle bit of rc-5 or rc-6 is enabled */
+#define LIRC_SCANCODE_FLAG_TOGGLE 1
+/* Set if this is a nec or sanyo repeat */
+#define LIRC_SCANCODE_FLAG_REPEAT 2
+
+/**
+ * enum rc_proto - the Remote Controller protocol
+ *
+ * @RC_PROTO_UNKNOWN: Protocol not known
+ * @RC_PROTO_OTHER: Protocol known but proprietary
+ * @RC_PROTO_RC5: Philips RC5 protocol
+ * @RC_PROTO_RC5X_20: Philips RC5x 20 bit protocol
+ * @RC_PROTO_RC5_SZ: StreamZap variant of RC5
+ * @RC_PROTO_JVC: JVC protocol
+ * @RC_PROTO_SONY12: Sony 12 bit protocol
+ * @RC_PROTO_SONY15: Sony 15 bit protocol
+ * @RC_PROTO_SONY20: Sony 20 bit protocol
+ * @RC_PROTO_NEC: NEC protocol
+ * @RC_PROTO_NECX: Extended NEC protocol
+ * @RC_PROTO_NEC32: NEC 32 bit protocol
+ * @RC_PROTO_SANYO: Sanyo protocol
+ * @RC_PROTO_MCIR2_KBD: RC6-ish MCE keyboard
+ * @RC_PROTO_MCIR2_MSE: RC6-ish MCE mouse
+ * @RC_PROTO_RC6_0: Philips RC6-0-16 protocol
+ * @RC_PROTO_RC6_6A_20: Philips RC6-6A-20 protocol
+ * @RC_PROTO_RC6_6A_24: Philips RC6-6A-24 protocol
+ * @RC_PROTO_RC6_6A_32: Philips RC6-6A-32 protocol
+ * @RC_PROTO_RC6_MCE: MCE (Philips RC6-6A-32 subtype) protocol
+ * @RC_PROTO_SHARP: Sharp protocol
+ * @RC_PROTO_XMP: XMP protocol
+ * @RC_PROTO_CEC: CEC protocol
+ * @RC_PROTO_IMON: iMon Pad protocol
+ */
+enum rc_proto {
+ RC_PROTO_UNKNOWN = 0,
+ RC_PROTO_OTHER = 1,
+ RC_PROTO_RC5 = 2,
+ RC_PROTO_RC5X_20 = 3,
+ RC_PROTO_RC5_SZ = 4,
+ RC_PROTO_JVC = 5,
+ RC_PROTO_SONY12 = 6,
+ RC_PROTO_SONY15 = 7,
+ RC_PROTO_SONY20 = 8,
+ RC_PROTO_NEC = 9,
+ RC_PROTO_NECX = 10,
+ RC_PROTO_NEC32 = 11,
+ RC_PROTO_SANYO = 12,
+ RC_PROTO_MCIR2_KBD = 13,
+ RC_PROTO_MCIR2_MSE = 14,
+ RC_PROTO_RC6_0 = 15,
+ RC_PROTO_RC6_6A_20 = 16,
+ RC_PROTO_RC6_6A_24 = 17,
+ RC_PROTO_RC6_6A_32 = 18,
+ RC_PROTO_RC6_MCE = 19,
+ RC_PROTO_SHARP = 20,
+ RC_PROTO_XMP = 21,
+ RC_PROTO_CEC = 22,
+ RC_PROTO_IMON = 23,
+};
+
+#endif
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index d20411ebfa2f..6cb45898afa7 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1462,6 +1462,7 @@ static bool bpf_prog_type__needs_kver(enum bpf_prog_type type)
case BPF_PROG_TYPE_CGROUP_DEVICE:
case BPF_PROG_TYPE_SK_MSG:
case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
+ case BPF_PROG_TYPE_LIRC_MODE2:
return false;
case BPF_PROG_TYPE_UNSPEC:
case BPF_PROG_TYPE_KPROBE:
diff --git a/tools/testing/selftests/bpf/.gitignore b/tools/testing/selftests/bpf/.gitignore
index adc8e5474b66..6ea835982464 100644
--- a/tools/testing/selftests/bpf/.gitignore
+++ b/tools/testing/selftests/bpf/.gitignore
@@ -17,3 +17,4 @@ test_sock_addr
urandom_read
test_btf
test_sockmap
+test_lirc_mode2_user
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 85044448bbc7..06400291e6e2 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -24,7 +24,7 @@ urandom_read: urandom_read.c
# Order correspond to 'make run_tests' order
TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \
test_align test_verifier_log test_dev_cgroup test_tcpbpf_user \
- test_sock test_btf test_sockmap
+ test_sock test_btf test_sockmap test_lirc_mode2_user

TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test_obj_id.o \
test_pkt_md_access.o test_xdp_redirect.o test_xdp_meta.o sockmap_parse_prog.o \
@@ -34,7 +34,7 @@ TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test
sockmap_tcp_msg_prog.o connect4_prog.o connect6_prog.o test_adjust_tail.o \
test_btf_haskv.o test_btf_nokv.o test_sockmap_kern.o test_tunnel_kern.o \
test_get_stack_rawtp.o test_sockmap_kern.o test_sockhash_kern.o \
- test_lwt_seg6local.o
+ test_lwt_seg6local.o test_lirc_mode2_kern.o

# Order correspond to 'make run_tests' order
TEST_PROGS := test_kmod.sh \
@@ -44,7 +44,8 @@ TEST_PROGS := test_kmod.sh \
test_offload.py \
test_sock_addr.sh \
test_tunnel.sh \
- test_lwt_seg6local.sh
+ test_lwt_seg6local.sh \
+ test_lirc_mode2.sh

# Compile but not part of 'make run_tests'
TEST_GEN_PROGS_EXTENDED = test_libbpf_open test_sock_addr
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index 334d3e8c5e89..a66a9d91acf4 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -126,6 +126,11 @@ static int (*bpf_lwt_seg6_action)(void *ctx, unsigned int action, void *param,
static int (*bpf_lwt_seg6_adjust_srh)(void *ctx, unsigned int offset,
unsigned int len) =
(void *) BPF_FUNC_lwt_seg6_adjust_srh;
+static int (*bpf_rc_repeat)(void *ctx) =
+ (void *) BPF_FUNC_rc_repeat;
+static int (*bpf_rc_keydown)(void *ctx, unsigned int protocol,
+ unsigned long long scancode, unsigned int toggle) =
+ (void *) BPF_FUNC_rc_keydown;

/* llvm builtin functions that eBPF C program may use to
* emit BPF_LD_ABS and BPF_LD_IND instructions
diff --git a/tools/testing/selftests/bpf/test_lirc_mode2.sh b/tools/testing/selftests/bpf/test_lirc_mode2.sh
new file mode 100755
index 000000000000..ce2e15e4f976
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_lirc_mode2.sh
@@ -0,0 +1,28 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+GREEN='\033[0;92m'
+RED='\033[0;31m'
+NC='\033[0m' # No Color
+
+modprobe rc-loopback
+
+for i in /sys/class/rc/rc*
+do
+ if grep -q DRV_NAME=rc-loopback $i/uevent
+ then
+ LIRCDEV=$(grep DEVNAME= $i/lirc*/uevent | sed sQDEVNAME=Q/dev/Q)
+ fi
+done
+
+if [ -n $LIRCDEV ];
+then
+ TYPE=lirc_mode2
+ ./test_lirc_mode2_user $LIRCDEV
+ ret=$?
+ if [ $ret -ne 0 ]; then
+ echo -e ${RED}"FAIL: $TYPE"${NC}
+ else
+ echo -e ${GREEN}"PASS: $TYPE"${NC}
+ fi
+fi
diff --git a/tools/testing/selftests/bpf/test_lirc_mode2_kern.c b/tools/testing/selftests/bpf/test_lirc_mode2_kern.c
new file mode 100644
index 000000000000..ba26855563a5
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_lirc_mode2_kern.c
@@ -0,0 +1,23 @@
+// SPDX-License-Identifier: GPL-2.0
+// test ir decoder
+//
+// Copyright (C) 2018 Sean Young <sean@xxxxxxxx>
+
+#include <linux/bpf.h>
+#include <linux/lirc.h>
+#include "bpf_helpers.h"
+
+SEC("lirc_mode2")
+int bpf_decoder(unsigned int *sample)
+{
+ if (LIRC_IS_PULSE(*sample)) {
+ unsigned int duration = LIRC_VALUE(*sample);
+
+ if (duration & 0x10000)
+ bpf_rc_keydown(sample, 0x40, duration & 0xffff, 0);
+ }
+
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_lirc_mode2_user.c b/tools/testing/selftests/bpf/test_lirc_mode2_user.c
new file mode 100644
index 000000000000..d470d63c33db
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_lirc_mode2_user.c
@@ -0,0 +1,149 @@
+// SPDX-License-Identifier: GPL-2.0
+// test ir decoder
+//
+// Copyright (C) 2018 Sean Young <sean@xxxxxxxx>
+
+// A lirc chardev is a device representing a consumer IR (cir) device which
+// can receive infrared signals from remote control and/or transmit IR.
+//
+// IR is sent as a series of pulses and space somewhat like morse code. The
+// BPF program can decode this into scancodes so that rc-core can translate
+// this into input key codes using the rc keymap.
+//
+// This test works by sending IR over rc-loopback, so the IR is processed by
+// BPF and then decoded into scancodes. The lirc chardev must be the one
+// associated with rc-loopback, see the output of ir-keytable(1).
+//
+// The following CONFIG options must be enabled for the test to succeed:
+// CONFIG_RC_CORE=y
+// CONFIG_BPF_RAWIR_EVENT=y
+// CONFIG_RC_LOOPBACK=y
+
+// Steps:
+// 1. Open the /dev/lircN device for rc-loopback (given on command line)
+// 2. Attach bpf_lirc_mode2 program which decodes some IR.
+// 3. Send some IR to the same IR device; since it is loopback, this will
+// end up in the bpf program
+// 4. bpf program should decode IR and report keycode
+// 5. We can read keycode from same /dev/lirc device
+
+#include <linux/bpf.h>
+#include <linux/lirc.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <poll.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include "bpf_util.h"
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+int main(int argc, char **argv)
+{
+ struct bpf_object *obj;
+ int ret, lircfd, progfd, mode;
+ int testir = 0x1dead;
+ u32 prog_ids[10], prog_flags[10], prog_cnt;
+
+ if (argc != 2) {
+ printf("Usage: %s /dev/lircN\n", argv[0]);
+ return 2;
+ }
+
+ ret = bpf_prog_load("test_lirc_mode2_kern.o",
+ BPF_PROG_TYPE_LIRC_MODE2, &obj, &progfd);
+ if (ret) {
+ printf("Failed to load bpf program\n");
+ return 1;
+ }
+
+ lircfd = open(argv[1], O_RDWR | O_NONBLOCK);
+ if (lircfd == -1) {
+ printf("failed to open lirc device %s: %m\n", argv[1]);
+ return 1;
+ }
+
+ /* Let's try detach it before it was ever attached */
+ ret = bpf_prog_detach2(progfd, lircfd, BPF_LIRC_MODE2);
+ if (ret != -1 || errno != ENOENT) {
+ printf("bpf_prog_detach2 not attached should fail: %m\n");
+ return 1;
+ }
+
+ mode = LIRC_MODE_SCANCODE;
+ if (ioctl(lircfd, LIRC_SET_REC_MODE, &mode)) {
+ printf("failed to set rec mode: %m\n");
+ return 1;
+ }
+
+ prog_cnt = 10;
+ ret = bpf_prog_query(lircfd, BPF_LIRC_MODE2, 0, prog_flags, prog_ids,
+ &prog_cnt);
+ if (ret) {
+ printf("Failed to query bpf programs on lirc device: %m\n");
+ return 1;
+ }
+
+ if (prog_cnt != 0) {
+ printf("Expected nothing to be attached\n");
+ return 1;
+ }
+
+ ret = bpf_prog_attach(progfd, lircfd, BPF_LIRC_MODE2, 0);
+ if (ret) {
+ printf("Failed to attach bpf to lirc device: %m\n");
+ return 1;
+ }
+
+ /* Write raw IR */
+ ret = write(lircfd, &testir, sizeof(testir));
+ if (ret != sizeof(testir)) {
+ printf("Failed to send test IR message: %m\n");
+ return 1;
+ }
+
+ struct pollfd pfd = { .fd = lircfd, .events = POLLIN };
+ struct lirc_scancode lsc;
+
+ poll(&pfd, 1, 100);
+
+ /* Read decoded IR */
+ ret = read(lircfd, &lsc, sizeof(lsc));
+ if (ret != sizeof(lsc)) {
+ printf("Failed to read decoded IR: %m\n");
+ return 1;
+ }
+
+ if (lsc.scancode != 0xdead || lsc.rc_proto != 64) {
+ printf("Incorrect scancode decoded\n");
+ return 1;
+ }
+
+ prog_cnt = 10;
+ ret = bpf_prog_query(lircfd, BPF_LIRC_MODE2, 0, prog_flags, prog_ids,
+ &prog_cnt);
+ if (ret) {
+ printf("Failed to query bpf programs on lirc device: %m\n");
+ return 1;
+ }
+
+ if (prog_cnt != 1) {
+ printf("Expected one program to be attached\n");
+ return 1;
+ }
+
+ /* Let's try detaching it now it is actually attached */
+ ret = bpf_prog_detach2(progfd, lircfd, BPF_LIRC_MODE2);
+ if (ret) {
+ printf("bpf_prog_detach2: returned %m\n");
+ return 1;
+ }
+
+ return 0;
+}
--
2.17.0