Some IR remotes have a directional pad or other pointer-like thing that
can be used as a mouse. Make it possible to decode these types of IR
protocols in BPF.
Cc: netdev@xxxxxxxxxxxxxxx
Signed-off-by: Sean Young <sean@xxxxxxxx>
---
drivers/media/rc/bpf-lirc.c | 24 +++++++++++++++++++++++
include/uapi/linux/bpf.h | 17 +++++++++++++++-
tools/testing/selftests/bpf/bpf_helpers.h | 2 ++
3 files changed, 42 insertions(+), 1 deletion(-)
diff --git a/drivers/media/rc/bpf-lirc.c b/drivers/media/rc/bpf-lirc.c
index 8b97fd1f0cea..390a722e6211 100644
--- a/drivers/media/rc/bpf-lirc.c
+++ b/drivers/media/rc/bpf-lirc.c
@@ -59,6 +59,28 @@ static const struct bpf_func_proto rc_keydown_proto = {
.arg4_type = ARG_ANYTHING,
};
+BPF_CALL_3(bpf_rc_pointer_rel, u32*, sample, s32, rel_x, s32, rel_y)
+{
+ struct ir_raw_event_ctrl *ctrl;
+
+ ctrl = container_of(sample, struct ir_raw_event_ctrl, bpf_sample);
+
+ input_report_rel(ctrl->dev->input_dev, REL_X, rel_x);
+ input_report_rel(ctrl->dev->input_dev, REL_Y, rel_y);
+ input_sync(ctrl->dev->input_dev);
+
+ return 0;
+}
+
+static const struct bpf_func_proto rc_pointer_rel_proto = {
+ .func = bpf_rc_pointer_rel,
+ .gpl_only = true,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_PTR_TO_CTX,
+ .arg2_type = ARG_ANYTHING,
+ .arg3_type = ARG_ANYTHING,
+};
+
static const struct bpf_func_proto *
lirc_mode2_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
{
@@ -67,6 +89,8 @@ lirc_mode2_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
return &rc_repeat_proto;
case BPF_FUNC_rc_keydown:
return &rc_keydown_proto;
+ case BPF_FUNC_rc_pointer_rel:
+ return &rc_pointer_rel_proto;
case BPF_FUNC_map_lookup_elem:
return &bpf_map_lookup_elem_proto;
case BPF_FUNC_map_update_elem:
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 23e2031a43d4..3499a1555bbf 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -2268,6 +2268,20 @@ union bpf_attr {
*
* Return
* 0 on success, or a negative error in case of failure.
+ *
+ * int bpf_rc_pointer_rel(void *ctx, s32 rel_x, s32 rel_y)
+ * Description
+ * This helper is used in programs implementing IR decoding, to
+ * report a successfully decoded pointer movement.
+ *
+ * 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), \
@@ -2360,7 +2374,8 @@ union bpf_attr {
FN(map_push_elem), \
FN(map_pop_elem), \
FN(map_peek_elem), \
- FN(msg_push_data),
+ FN(msg_push_data), \
+ FN(rc_pointer_rel),
/* integer value in 'imm' field of BPF_CALL instruction selects which helper
* function eBPF program intends to call
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index 686e57ce40f4..5c900a917fa4 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -168,6 +168,8 @@ static int (*bpf_skb_vlan_push)(void *ctx, __be16 vlan_proto, __u16 vlan_tci) =
(void *) BPF_FUNC_skb_vlan_push;
static int (*bpf_skb_vlan_pop)(void *ctx) =
(void *) BPF_FUNC_skb_vlan_pop;
+static int (*bpf_rc_pointer_rel)(void *ctx, int rel_x, int rel_y) =
+ (void *) BPF_FUNC_rc_pointer_rel;
/* llvm builtin functions that eBPF C program may use to
* emit BPF_LD_ABS and BPF_LD_IND instructions
--
2.19.1
