HID: uclogic: Support v2 protocol (2c3a88c6) · Commits · git / linux-net

drivers/hid/hid-uclogic-params.c

+201 −0

Original line number	Diff line number	Diff line
		@@ -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);
		}

		/**
		* 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;
		}

drivers/hid/hid-uclogic-rdesc.c

+63 −0

Original line number	Diff line number	Diff line
		@@ -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

drivers/hid/hid-uclogic-rdesc.h

+14 −0

Original line number	Diff line number	Diff line
		@@ -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 */