1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * HID driver for UC-Logic devices not fully compliant with HID standard 4 * - tablet initialization and parameter retrieval 5 * 6 * Copyright (c) 2018 Nikolai Kondrashov 7 */ 8 9 /* 10 * This program is free software; you can redistribute it and/or modify it 11 * under the terms of the GNU General Public License as published by the Free 12 * Software Foundation; either version 2 of the License, or (at your option) 13 * any later version. 14 */ 15 16 #ifndef _HID_UCLOGIC_PARAMS_H 17 #define _HID_UCLOGIC_PARAMS_H 18 19 #include <linux/usb.h> 20 #include <linux/hid.h> 21 22 /* Types of pen in-range reporting */ 23 enum uclogic_params_pen_inrange { 24 /* Normal reports: zero - out of proximity, one - in proximity */ 25 UCLOGIC_PARAMS_PEN_INRANGE_NORMAL = 0, 26 /* Inverted reports: zero - in proximity, one - out of proximity */ 27 UCLOGIC_PARAMS_PEN_INRANGE_INVERTED, 28 /* No reports */ 29 UCLOGIC_PARAMS_PEN_INRANGE_NONE, 30 }; 31 32 /* Types of frames */ 33 enum uclogic_params_frame_type { 34 /* Frame with buttons */ 35 UCLOGIC_PARAMS_FRAME_BUTTONS = 0, 36 /* Frame with buttons and a dial */ 37 UCLOGIC_PARAMS_FRAME_DIAL, 38 /* Frame with buttons and a mouse (shaped as a dial + touchpad) */ 39 UCLOGIC_PARAMS_FRAME_MOUSE, 40 }; 41 42 /* 43 * Pen report's subreport data. 44 */ 45 struct uclogic_params_pen_subreport { 46 /* 47 * The value of the second byte of the pen report indicating this 48 * subreport. If zero, the subreport should be considered invalid and 49 * not matched. 50 */ 51 __u8 value; 52 53 /* 54 * The ID to be assigned to the report, if the second byte of the pen 55 * report is equal to "value". Only valid if "value" is not zero. 56 */ 57 __u8 id; 58 }; 59 60 /* 61 * Tablet interface's pen input parameters. 62 * 63 * Must use declarative (descriptive) language, not imperative, to simplify 64 * understanding and maintain consistency. 65 * 66 * Noop (preserving functionality) when filled with zeroes. 67 */ 68 struct uclogic_params_pen { 69 /* 70 * True if pen usage is invalid for this interface and should be 71 * ignored, false otherwise. 72 */ 73 bool usage_invalid; 74 /* 75 * Pointer to report descriptor part describing the pen inputs. 76 * Allocated with kmalloc. NULL if the part is not specified. 77 */ 78 __u8 *desc_ptr; 79 /* 80 * Size of the report descriptor. 81 * Only valid, if "desc_ptr" is not NULL. 82 */ 83 unsigned int desc_size; 84 /* Report ID, if reports should be tweaked, zero if not */ 85 unsigned int id; 86 /* The list of subreports, only valid if "id" is not zero */ 87 struct uclogic_params_pen_subreport subreport_list[3]; 88 /* Type of in-range reporting, only valid if "id" is not zero */ 89 enum uclogic_params_pen_inrange inrange; 90 /* 91 * True, if reports include fragmented high resolution coords, with 92 * high-order X and then Y bytes following the pressure field. 93 * Only valid if "id" is not zero. 94 */ 95 bool fragmented_hires; 96 /* 97 * True if the pen reports tilt in bytes at offset 10 (X) and 11 (Y), 98 * and the Y tilt direction is flipped. 99 * Only valid if "id" is not zero. 100 */ 101 bool tilt_y_flipped; 102 }; 103 104 /* 105 * Parameters of frame control inputs of a tablet interface. 106 * 107 * Must use declarative (descriptive) language, not imperative, to simplify 108 * understanding and maintain consistency. 109 * 110 * Noop (preserving functionality) when filled with zeroes. 111 */ 112 struct uclogic_params_frame { 113 /* 114 * Pointer to report descriptor part describing the frame inputs. 115 * Allocated with kmalloc. NULL if the part is not specified. 116 */ 117 __u8 *desc_ptr; 118 /* 119 * Size of the report descriptor. 120 * Only valid, if "desc_ptr" is not NULL. 121 */ 122 unsigned int desc_size; 123 /* 124 * Report ID, if reports should be tweaked, zero if not. 125 */ 126 unsigned int id; 127 /* 128 * The suffix to add to the input device name, if not NULL. 129 */ 130 const char *suffix; 131 /* 132 * Number of the least-significant bit of the 2-bit state of a rotary 133 * encoder, in the report. Cannot point to a 2-bit field crossing a 134 * byte boundary. Zero if not present. Only valid if "id" is not zero. 135 */ 136 unsigned int re_lsb; 137 /* 138 * Offset of the Wacom-style device ID byte in the report, to be set 139 * to pad device ID (0xf), for compatibility with Wacom drivers. Zero 140 * if no changes to the report should be made. The ID byte will be set 141 * to zero whenever the byte pointed by "touch_byte" is zero, if 142 * the latter is valid. Only valid if "id" is not zero. 143 */ 144 unsigned int dev_id_byte; 145 /* 146 * Offset of the touch ring/strip state byte, in the report. 147 * Zero if not present. If dev_id_byte is also valid and non-zero, 148 * then the device ID byte will be cleared when the byte pointed to by 149 * this offset is zero. Only valid if "id" is not zero. 150 */ 151 unsigned int touch_byte; 152 /* 153 * The value to anchor the reversed touch ring/strip reports at. 154 * I.e. one, if the reports should be flipped without offset. 155 * Zero if no reversal should be done. 156 * Only valid if "touch_byte" is valid and not zero. 157 */ 158 __s8 touch_flip_at; 159 /* 160 * Maximum value of the touch ring/strip report around which the value 161 * should be wrapped when flipping according to "touch_flip_at". 162 * The minimum valid value is considered to be one, with zero being 163 * out-of-proximity (finger lift) value. 164 * Only valid if "touch_flip_at" is valid and not zero. 165 */ 166 __s8 touch_max; 167 /* 168 * Offset of the bitmap dial byte, in the report. Zero if not present. 169 * Only valid if "id" is not zero. A bitmap dial sends reports with a 170 * dedicated bit per direction: 1 means clockwise rotation, 2 means 171 * counterclockwise, as opposed to the normal 1 and -1. 172 */ 173 unsigned int bitmap_dial_byte; 174 }; 175 176 /* 177 * Tablet interface report parameters. 178 * 179 * Must use declarative (descriptive) language, not imperative, to simplify 180 * understanding and maintain consistency. 181 * 182 * When filled with zeros represents a "noop" configuration - passes all 183 * reports unchanged and lets the generic HID driver handle everything. 184 * 185 * The resulting device report descriptor is assembled from all the report 186 * descriptor parts referenced by the structure. No order of assembly should 187 * be assumed. The structure represents original device report descriptor if 188 * all the parts are NULL. 189 */ 190 struct uclogic_params { 191 /* 192 * True if the whole interface is invalid, false otherwise. 193 */ 194 bool invalid; 195 /* 196 * Pointer to the common part of the replacement report descriptor, 197 * allocated with kmalloc. NULL if no common part is needed. 198 * Only valid, if "invalid" is false. 199 */ 200 __u8 *desc_ptr; 201 /* 202 * Size of the common part of the replacement report descriptor. 203 * Only valid, if "desc_ptr" is valid and not NULL. 204 */ 205 unsigned int desc_size; 206 /* 207 * Pen parameters and optional report descriptor part. 208 * Only valid, if "invalid" is false. 209 */ 210 struct uclogic_params_pen pen; 211 /* 212 * The list of frame control parameters and optional report descriptor 213 * parts. Only valid, if "invalid" is false. 214 */ 215 struct uclogic_params_frame frame_list[3]; 216 }; 217 218 /* Initialize a tablet interface and discover its parameters */ 219 extern int uclogic_params_init(struct uclogic_params *params, 220 struct hid_device *hdev); 221 222 /* Get a replacement report descriptor for a tablet's interface. */ 223 extern int uclogic_params_get_desc(const struct uclogic_params *params, 224 __u8 **pdesc, 225 unsigned int *psize); 226 227 /* Free resources used by tablet interface's parameters */ 228 extern void uclogic_params_cleanup(struct uclogic_params *params); 229 230 /* Dump tablet interface parameters with hid_dbg() */ 231 extern void uclogic_params_hid_dbg(const struct hid_device *hdev, 232 const struct uclogic_params *params); 233 234 #endif /* _HID_UCLOGIC_PARAMS_H */ 235