On Sun, Feb 10, 2019 at 11:15 AM Nikolai Kondrashov <spbnick@xxxxxxxxx> wrote:
>
> Add support for UC-Logic v2 protocol to hid-uclogic.
> This adds support for a bunch of new Huion models.
>
> Signed-off-by: Nikolai Kondrashov <spbnick@xxxxxxxxx>
> ---
> drivers/hid/hid-uclogic-params.c | 201 +++++++++++++++++++++++++++++++
> drivers/hid/hid-uclogic-rdesc.c | 63 ++++++++++
> drivers/hid/hid-uclogic-rdesc.h | 14 +++
> 3 files changed, 278 insertions(+)
>
> diff --git a/drivers/hid/hid-uclogic-params.c b/drivers/hid/hid-uclogic-params.c
> index b5e4d99c6771..132663a87f38 100644
> --- a/drivers/hid/hid-uclogic-params.c
> +++ b/drivers/hid/hid-uclogic-params.c
> @@ -231,6 +231,151 @@ static int uclogic_params_pen_init_v1(struct uclogic_params_pen *pen,
> return rc;
> }
>
> +/**
> + * uclogic_params_get_le24() - get a 24-bit little-endian number from a
> + * buffer.
> + *
> + * @p: The pointer to the number buffer.
> + *
> + * Returns:
> + * The retrieved number
> + */
> +static s32 uclogic_params_get_le24(const void *p)
> +{
> + const __u8 *b = p;
> + return b[0] | (b[1] << 8UL) | (b[2] << 16UL);
Nitpick, I am pretty sure we already have the bits in the kernel for that.
But OTOH, not sure I'll request a v3 just for that.
Cheers,
Benjamin
> +}
> +
> +/**
> + * uclogic_params_pen_init_v2() - initialize tablet interface pen
> + * input and retrieve its parameters from the device, using v2 protocol.
> + *
> + * @pen: Pointer to the pen parameters to initialize (to be
> + * cleaned up with uclogic_params_pen_cleanup()). Not modified in
> + * case of error, or if parameters are not found. Cannot be NULL.
> + * @pfound: Location for a flag which is set to true if the parameters
> + * were found, and to false if not (e.g. device was
> + * incompatible). Not modified in case of error. Cannot be NULL.
> + * @hdev: The HID device of the tablet interface to initialize and get
> + * parameters from. Cannot be NULL.
> + *
> + * Returns:
> + * Zero, if successful. A negative errno code on error.
> + */
> +static int uclogic_params_pen_init_v2(struct uclogic_params_pen *pen,
> + bool *pfound,
> + struct hid_device *hdev)
> +{
> + int rc;
> + bool found = false;
> + /* Buffer for (part of) the string descriptor */
> + __u8 *buf = NULL;
> + /* Descriptor length required */
> + const int len = 18;
> + s32 resolution;
> + /* Pen report descriptor template parameters */
> + s32 desc_params[UCLOGIC_RDESC_PEN_PH_ID_NUM];
> + __u8 *desc_ptr = NULL;
> +
> + /* Check arguments */
> + if (pen == NULL || pfound == NULL || hdev == NULL) {
> + rc = -EINVAL;
> + goto cleanup;
> + }
> +
> + /*
> + * Read string descriptor containing pen input parameters.
> + * The specific string descriptor and data were discovered by sniffing
> + * the Windows driver traffic.
> + * NOTE: This enables fully-functional tablet mode.
> + */
> + rc = uclogic_params_get_str_desc(&buf, hdev, 200, len);
> + if (rc == -EPIPE) {
> + hid_dbg(hdev,
> + "string descriptor with pen parameters not found, assuming not compatible\n");
> + goto finish;
> + } else if (rc < 0) {
> + hid_err(hdev, "failed retrieving pen parameters: %d\n", rc);
> + goto cleanup;
> + } else if (rc != len) {
> + hid_dbg(hdev,
> + "string descriptor with pen parameters has invalid length (got %d, expected %d), assuming not compatible\n",
> + rc, len);
> + goto finish;
> + } else {
> + size_t i;
> + /*
> + * Check it's not just a catch-all UTF-16LE-encoded ASCII
> + * string (such as the model name) some tablets put into all
> + * unknown string descriptors.
> + */
> + for (i = 2;
> + i < len &&
> + (buf[i] >= 0x20 && buf[i] < 0x7f && buf[i + 1] == 0);
> + i += 2);
> + if (i >= len) {
> + hid_dbg(hdev,
> + "string descriptor with pen parameters seems to contain only text, assuming not compatible\n");
> + goto finish;
> + }
> + }
> +
> + /*
> + * Fill report descriptor parameters from the string descriptor
> + */
> + desc_params[UCLOGIC_RDESC_PEN_PH_ID_X_LM] =
> + uclogic_params_get_le24(buf + 2);
> + desc_params[UCLOGIC_RDESC_PEN_PH_ID_Y_LM] =
> + uclogic_params_get_le24(buf + 5);
> + desc_params[UCLOGIC_RDESC_PEN_PH_ID_PRESSURE_LM] =
> + get_unaligned_le16(buf + 8);
> + resolution = get_unaligned_le16(buf + 10);
> + if (resolution == 0) {
> + desc_params[UCLOGIC_RDESC_PEN_PH_ID_X_PM] = 0;
> + desc_params[UCLOGIC_RDESC_PEN_PH_ID_Y_PM] = 0;
> + } else {
> + desc_params[UCLOGIC_RDESC_PEN_PH_ID_X_PM] =
> + desc_params[UCLOGIC_RDESC_PEN_PH_ID_X_LM] * 1000 /
> + resolution;
> + desc_params[UCLOGIC_RDESC_PEN_PH_ID_Y_PM] =
> + desc_params[UCLOGIC_RDESC_PEN_PH_ID_Y_LM] * 1000 /
> + resolution;
> + }
> + kfree(buf);
> + buf = NULL;
> +
> + /*
> + * Generate pen report descriptor
> + */
> + desc_ptr = uclogic_rdesc_template_apply(
> + uclogic_rdesc_pen_v2_template_arr,
> + uclogic_rdesc_pen_v2_template_size,
> + desc_params, ARRAY_SIZE(desc_params));
> + if (desc_ptr == NULL) {
> + rc = -ENOMEM;
> + goto cleanup;
> + }
> +
> + /*
> + * Fill-in the parameters
> + */
> + memset(pen, 0, sizeof(*pen));
> + pen->desc_ptr = desc_ptr;
> + desc_ptr = NULL;
> + pen->desc_size = uclogic_rdesc_pen_v2_template_size;
> + pen->id = UCLOGIC_RDESC_PEN_V2_ID;
> + pen->inrange = UCLOGIC_PARAMS_PEN_INRANGE_NONE;
> + pen->fragmented_hires = true;
> + found = true;
> +finish:
> + *pfound = found;
> + rc = 0;
> +cleanup:
> + kfree(desc_ptr);
> + kfree(buf);
> + return rc;
> +}
> +
> /**
> * uclogic_params_frame_cleanup - free resources used by struct
> * uclogic_params_frame (tablet interface's frame controls input parameters).
> @@ -560,11 +705,15 @@ static int uclogic_params_huion_init(struct uclogic_params *params,
> struct hid_device *hdev)
> {
> int rc;
> + struct usb_device *udev = hid_to_usb_dev(hdev);
> struct usb_interface *iface = to_usb_interface(hdev->dev.parent);
> __u8 bInterfaceNumber = iface->cur_altsetting->desc.bInterfaceNumber;
> bool found;
> /* The resulting parameters (noop) */
> struct uclogic_params p = {0, };
> + static const char transition_ver[] = "HUION_T153_160607";
> + char *ver_ptr = NULL;
> + const size_t ver_len = sizeof(transition_ver) + 1;
>
> /* Check arguments */
> if (params == NULL || hdev == NULL) {
> @@ -579,6 +728,57 @@ static int uclogic_params_huion_init(struct uclogic_params *params,
> goto output;
> }
>
> + /* Try to get firmware version */
> + ver_ptr = kzalloc(ver_len, GFP_KERNEL);
> + if (ver_ptr == NULL) {
> + rc = -ENOMEM;
> + goto cleanup;
> + }
> + rc = usb_string(udev, 201, ver_ptr, ver_len);
> + if (ver_ptr == NULL) {
> + rc = -ENOMEM;
> + goto cleanup;
> + }
> + if (rc == -EPIPE) {
> + *ver_ptr = '\0';
> + } else if (rc < 0) {
> + hid_err(hdev,
> + "failed retrieving Huion firmware version: %d\n", rc);
> + goto cleanup;
> + }
> +
> + /* If this is a transition firmware */
> + if (strcmp(ver_ptr, transition_ver) == 0) {
> + hid_dbg(hdev,
> + "transition firmware detected, not probing pen v2 parameters\n");
> + } else {
> + /* Try to probe v2 pen parameters */
> + rc = uclogic_params_pen_init_v2(&p.pen, &found, hdev);
> + if (rc != 0) {
> + hid_err(hdev,
> + "failed probing pen v2 parameters: %d\n", rc);
> + goto cleanup;
> + } else if (found) {
> + hid_dbg(hdev, "pen v2 parameters found\n");
> + /* Create v2 buttonpad parameters */
> + rc = uclogic_params_frame_init_with_desc(
> + &p.frame,
> + uclogic_rdesc_buttonpad_v2_arr,
> + uclogic_rdesc_buttonpad_v2_size,
> + UCLOGIC_RDESC_BUTTONPAD_V2_ID);
> + if (rc != 0) {
> + hid_err(hdev,
> + "failed creating v2 buttonpad parameters: %d\n",
> + rc);
> + goto cleanup;
> + }
> + /* Set bitmask marking frame reports in pen reports */
> + p.pen_frame_flag = 0x20;
> + goto output;
> + }
> + hid_dbg(hdev, "pen v2 parameters not found\n");
> + }
> +
> /* Try to probe v1 pen parameters */
> rc = uclogic_params_pen_init_v1(&p.pen, &found, hdev);
> if (rc != 0) {
> @@ -613,6 +813,7 @@ static int uclogic_params_huion_init(struct uclogic_params *params,
> memset(&p, 0, sizeof(p));
> rc = 0;
> cleanup:
> + kfree(ver_ptr);
> uclogic_params_cleanup(&p);
> return rc;
> }
> diff --git a/drivers/hid/hid-uclogic-rdesc.c b/drivers/hid/hid-uclogic-rdesc.c
> index 359e72394d83..ef1d3cf918a4 100644
> --- a/drivers/hid/hid-uclogic-rdesc.c
> +++ b/drivers/hid/hid-uclogic-rdesc.c
> @@ -585,6 +585,62 @@ const __u8 uclogic_rdesc_pen_v1_template_arr[] = {
> const size_t uclogic_rdesc_pen_v1_template_size =
> sizeof(uclogic_rdesc_pen_v1_template_arr);
>
> +/* Fixed report descriptor template for (tweaked) v2 pen reports */
> +const __u8 uclogic_rdesc_pen_v2_template_arr[] = {
> + 0x05, 0x0D, /* Usage Page (Digitizer), */
> + 0x09, 0x02, /* Usage (Pen), */
> + 0xA1, 0x01, /* Collection (Application), */
> + 0x85, 0x08, /* Report ID (8), */
> + 0x09, 0x20, /* Usage (Stylus), */
> + 0xA0, /* Collection (Physical), */
> + 0x14, /* Logical Minimum (0), */
> + 0x25, 0x01, /* Logical Maximum (1), */
> + 0x75, 0x01, /* Report Size (1), */
> + 0x09, 0x42, /* Usage (Tip Switch), */
> + 0x09, 0x44, /* Usage (Barrel Switch), */
> + 0x09, 0x46, /* Usage (Tablet Pick), */
> + 0x95, 0x03, /* Report Count (3), */
> + 0x81, 0x02, /* Input (Variable), */
> + 0x95, 0x03, /* Report Count (3), */
> + 0x81, 0x03, /* Input (Constant, Variable), */
> + 0x09, 0x32, /* Usage (In Range), */
> + 0x95, 0x01, /* Report Count (1), */
> + 0x81, 0x02, /* Input (Variable), */
> + 0x95, 0x01, /* Report Count (1), */
> + 0x81, 0x03, /* Input (Constant, Variable), */
> + 0x95, 0x01, /* Report Count (1), */
> + 0xA4, /* Push, */
> + 0x05, 0x01, /* Usage Page (Desktop), */
> + 0x65, 0x13, /* Unit (Inch), */
> + 0x55, 0xFD, /* Unit Exponent (-3), */
> + 0x75, 0x18, /* Report Size (24), */
> + 0x34, /* Physical Minimum (0), */
> + 0x09, 0x30, /* Usage (X), */
> + 0x27, UCLOGIC_RDESC_PEN_PH(X_LM),
> + /* Logical Maximum (PLACEHOLDER), */
> + 0x47, UCLOGIC_RDESC_PEN_PH(X_PM),
> + /* Physical Maximum (PLACEHOLDER), */
> + 0x81, 0x02, /* Input (Variable), */
> + 0x09, 0x31, /* Usage (Y), */
> + 0x27, UCLOGIC_RDESC_PEN_PH(Y_LM),
> + /* Logical Maximum (PLACEHOLDER), */
> + 0x47, UCLOGIC_RDESC_PEN_PH(Y_PM),
> + /* Physical Maximum (PLACEHOLDER), */
> + 0x81, 0x02, /* Input (Variable), */
> + 0xB4, /* Pop, */
> + 0x09, 0x30, /* Usage (Tip Pressure), */
> + 0x75, 0x10, /* Report Size (16), */
> + 0x27, UCLOGIC_RDESC_PEN_PH(PRESSURE_LM),
> + /* Logical Maximum (PLACEHOLDER), */
> + 0x81, 0x02, /* Input (Variable), */
> + 0x81, 0x03, /* Input (Constant, Variable), */
> + 0xC0, /* End Collection, */
> + 0xC0 /* End Collection */
> +};
> +
> +const size_t uclogic_rdesc_pen_v2_template_size =
> + sizeof(uclogic_rdesc_pen_v2_template_arr);
> +
> /**
> * Expand to the contents of a generic buttonpad report descriptor.
> *
> @@ -638,6 +694,13 @@ const __u8 uclogic_rdesc_buttonpad_v1_arr[] = {
> const size_t uclogic_rdesc_buttonpad_v1_size =
> sizeof(uclogic_rdesc_buttonpad_v1_arr);
>
> +/* Fixed report descriptor for (tweaked) v2 buttonpad reports */
> +const __u8 uclogic_rdesc_buttonpad_v2_arr[] = {
> + UCLOGIC_RDESC_BUTTONPAD_BYTES(52)
> +};
> +const size_t uclogic_rdesc_buttonpad_v2_size =
> + sizeof(uclogic_rdesc_buttonpad_v2_arr);
> +
> /**
> * uclogic_rdesc_template_apply() - apply report descriptor parameters to a
> * report descriptor template, creating a report descriptor. Copies the
> diff --git a/drivers/hid/hid-uclogic-rdesc.h b/drivers/hid/hid-uclogic-rdesc.h
> index cf03b98ae7cb..f205254a733c 100644
> --- a/drivers/hid/hid-uclogic-rdesc.h
> +++ b/drivers/hid/hid-uclogic-rdesc.h
> @@ -107,6 +107,13 @@ enum uclogic_rdesc_pen_ph_id {
> extern const __u8 uclogic_rdesc_pen_v1_template_arr[];
> extern const size_t uclogic_rdesc_pen_v1_template_size;
>
> +/* Report ID for v2 pen reports */
> +#define UCLOGIC_RDESC_PEN_V2_ID 0x08
> +
> +/* Fixed report descriptor template for (tweaked) v2 pen reports */
> +extern const __u8 uclogic_rdesc_pen_v2_template_arr[];
> +extern const size_t uclogic_rdesc_pen_v2_template_size;
> +
> /* Fixed report descriptor for (tweaked) v1 buttonpad reports */
> extern const __u8 uclogic_rdesc_buttonpad_v1_arr[];
> extern const size_t uclogic_rdesc_buttonpad_v1_size;
> @@ -114,4 +121,11 @@ extern const size_t uclogic_rdesc_buttonpad_v1_size;
> /* Report ID for tweaked v1 buttonpad reports */
> #define UCLOGIC_RDESC_BUTTONPAD_V1_ID 0xf7
>
> +/* Fixed report descriptor for (tweaked) v2 buttonpad reports */
> +extern const __u8 uclogic_rdesc_buttonpad_v2_arr[];
> +extern const size_t uclogic_rdesc_buttonpad_v2_size;
> +
> +/* Report ID for tweaked v2 buttonpad reports */
> +#define UCLOGIC_RDESC_BUTTONPAD_V2_ID 0xf7
> +
> #endif /* _HID_UCLOGIC_RDESC_H */
> --
> 2.20.1
>
