On Thu, Dec 1, 2022 at 3:11 PM Jason Gerecke <killertofu@xxxxxxxxx> wrote:
>
> From: Jason Gerecke <killertofu@xxxxxxxxx>
>
> Some Wacom devices have a special "bootloader" mode that is used for
> firmware flashing. When operating in this mode, the device cannot be
> used for input, and the HID descriptor is not able to be processed by
> the driver. The driver generates an "Unknown device_type" warning and
> then returns an error code from wacom_probe(). This is a problem because
> userspace still needs to be able to interact with the device via hidraw
> to perform the firmware flash.
>
> This commit adds a non-generic device definition for 056a:0094 which
> is used when devices are in "bootloader" mode. It marks the devices
> with a special BOOTLOADER type that is recognized by wacom_probe() and
> wacom_raw_event(). When we see this type we ensure a hidraw device is
> created and otherwise keep our hands off so that userspace is in full
> control.
>
> Signed-off-by: Jason Gerecke <jason.gerecke@xxxxxxxxx>
> Tested-by: Tatsunosuke Tobita <tatsunosuke.tobita@xxxxxxxxx>
> Cc: <stable@xxxxxxxxxxxxxxx>
> ---
> drivers/hid/wacom_sys.c | 8 ++++++++
> drivers/hid/wacom_wac.c | 4 ++++
> drivers/hid/wacom_wac.h | 1 +
> 3 files changed, 13 insertions(+)
>
> diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c
> index 634263e4556b..fb538a6c4add 100644
> --- a/drivers/hid/wacom_sys.c
> +++ b/drivers/hid/wacom_sys.c
> @@ -155,6 +155,9 @@ static int wacom_raw_event(struct hid_device *hdev, struct hid_report *report,
> {
> struct wacom *wacom = hid_get_drvdata(hdev);
>
> + if (wacom->wacom_wac.features.type == BOOTLOADER)
> + return 0;
> +
> if (size > WACOM_PKGLEN_MAX)
> return 1;
>
> @@ -2785,6 +2788,11 @@ static int wacom_probe(struct hid_device *hdev,
> return error;
> }
>
> + if (features->type == BOOTLOADER) {
> + hid_warn(hdev, "Using device in hidraw-only mode");
> + return hid_hw_start(hdev, HID_CONNECT_HIDRAW);
> + }
> +
> error = wacom_parse_and_register(wacom, false);
> if (error)
> return error;
> diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c
> index 0f3d57b42684..9312d611db8e 100644
> --- a/drivers/hid/wacom_wac.c
> +++ b/drivers/hid/wacom_wac.c
> @@ -4882,6 +4882,9 @@ static const struct wacom_features wacom_features_0x3dd =
> static const struct wacom_features wacom_features_HID_ANY_ID =
> { "Wacom HID", .type = HID_GENERIC, .oVid = HID_ANY_ID, .oPid = HID_ANY_ID };
>
> +static const struct wacom_features wacom_features_0x94 =
> + { "Wacom Bootloader", .type = BOOTLOADER };
> +
> #define USB_DEVICE_WACOM(prod) \
> HID_DEVICE(BUS_USB, HID_GROUP_WACOM, USB_VENDOR_ID_WACOM, prod),\
> .driver_data = (kernel_ulong_t)&wacom_features_##prod
> @@ -4955,6 +4958,7 @@ const struct hid_device_id wacom_ids[] = {
> { USB_DEVICE_WACOM(0x84) },
> { USB_DEVICE_WACOM(0x90) },
> { USB_DEVICE_WACOM(0x93) },
> + { USB_DEVICE_WACOM(0x94) },
> { USB_DEVICE_WACOM(0x97) },
> { USB_DEVICE_WACOM(0x9A) },
> { USB_DEVICE_WACOM(0x9F) },
> diff --git a/drivers/hid/wacom_wac.h b/drivers/hid/wacom_wac.h
> index 5ca6c06d143b..16f221388563 100644
> --- a/drivers/hid/wacom_wac.h
> +++ b/drivers/hid/wacom_wac.h
> @@ -243,6 +243,7 @@ enum {
> MTTPC,
> MTTPC_B,
> HID_GENERIC,
> + BOOTLOADER,
> MAX_TYPE
> };
>
> --
> 2.38.1
>
Haven't seen any action on this so sending it out again.
Jason
---
Now instead of four in the eights place /
you’ve got three, ‘Cause you added one /
(That is to say, eight) to the two, /
But you can’t take seven from three, /
So you look at the sixty-fours....
