On Thu, Dec 1, 2022 at 3:11 PM Jason Gerecke killertofu@gmail.com wrote:

From: Jason Gerecke killertofu@gmail.com

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@wacom.com Tested-by: Tatsunosuke Tobita tatsunosuke.tobita@wacom.com Cc: stable@vger.kernel.org

---

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....