Duplicate of commit 0db117359e47 ("HID: add quirk for 03f0:464a HP Elite Presenter Mouse"), but in a slightly better way.
This time we actually change the application collection, making clearer for userspace what the second mouse is.
Note that having both hid-quirks fix and this HID-BPF fix is not a problem at all.
Signed-off-by: Benjamin Tissoires bentiss@kernel.org --- drivers/hid/bpf/progs/HP__Elite-Presenter.bpf.c | 58 +++++++++++++++++++++++++ 1 file changed, 58 insertions(+)
diff --git a/drivers/hid/bpf/progs/HP__Elite-Presenter.bpf.c b/drivers/hid/bpf/progs/HP__Elite-Presenter.bpf.c new file mode 100644 index 000000000000..3d14bbb6f276 --- /dev/null +++ b/drivers/hid/bpf/progs/HP__Elite-Presenter.bpf.c @@ -0,0 +1,58 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2023 Benjamin Tissoires + */ + +#include "vmlinux.h" +#include "hid_bpf.h" +#include "hid_bpf_helpers.h" +#include <bpf/bpf_tracing.h> + +#define VID_HP 0x03F0 +#define PID_ELITE_PRESENTER 0x464A + +HID_BPF_CONFIG( + HID_DEVICE(BUS_BLUETOOTH, HID_GROUP_GENERIC, VID_HP, PID_ELITE_PRESENTER) +); + +/* + * Already fixed as of commit 0db117359e47 ("HID: add quirk for 03f0:464a + * HP Elite Presenter Mouse") in the kernel, but this is a slightly better + * fix. + * + * The HP Elite Presenter Mouse HID Record Descriptor shows + * two mice (Report ID 0x1 and 0x2), one keypad (Report ID 0x5), + * two Consumer Controls (Report IDs 0x6 and 0x3). + * Prior to these fixes it registers one mouse, one keypad + * and one Consumer Control, and it was usable only as a + * digital laser pointer (one of the two mouses). + * We replace the second mouse collection with a pointer collection, + * allowing to use the device both as a mouse and a digital laser + * pointer. + */ + +SEC("fmod_ret/hid_bpf_rdesc_fixup") +int BPF_PROG(hid_fix_rdesc, struct hid_bpf_ctx *hctx) +{ + __u8 *data = hid_bpf_get_data(hctx, 0 /* offset */, 4096 /* size */); + + if (!data) + return 0; /* EPERM check */ + + /* replace application mouse by application pointer on the second collection */ + if (data[79] == 0x02) + data[79] = 0x01; + + return 0; +} + +SEC("syscall") +int probe(struct hid_bpf_probe_args *ctx) +{ + ctx->retval = ctx->rdesc_size != 264; + if (ctx->retval) + ctx->retval = -EINVAL; + + return 0; +} + +char _license[] SEC("license") = "GPL";