/* SPDX-License-Identifier: GPL-2.0+ */ /* * HID driver for UC-Logic devices not fully compliant with HID standard * - tablet initialization and parameter retrieval * * Copyright (c) 2018 Nikolai Kondrashov */ /* * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the Free * Software Foundation; either version 2 of the License, or (at your option) * any later version. */ #ifndef _HID_UCLOGIC_PARAMS_H #define _HID_UCLOGIC_PARAMS_H #include <linux/usb.h> #include <linux/hid.h> /* Types of pen in-range reporting */ enum uclogic_params_pen_inrange { /* Normal reports: zero - out of proximity, one - in proximity */ UCLOGIC_PARAMS_PEN_INRANGE_NORMAL = 0, /* Inverted reports: zero - in proximity, one - out of proximity */ UCLOGIC_PARAMS_PEN_INRANGE_INVERTED, /* No reports */ UCLOGIC_PARAMS_PEN_INRANGE_NONE, }; /* Convert a pen in-range reporting type to a string */ extern const char *uclogic_params_pen_inrange_to_str( enum uclogic_params_pen_inrange inrange); /* * Tablet interface's pen input parameters. * * Must use declarative (descriptive) language, not imperative, to simplify * understanding and maintain consistency. * * Noop (preserving functionality) when filled with zeroes. */ struct uclogic_params_pen { /* * Pointer to report descriptor describing the inputs. * Allocated with kmalloc. */ __u8 *desc_ptr; /* * Size of the report descriptor. * Only valid, if "desc_ptr" is not NULL. */ unsigned int desc_size; /* Report ID, if reports should be tweaked, zero if not */ unsigned int id; /* Type of in-range reporting, only valid if "id" is not zero */ enum uclogic_params_pen_inrange inrange; /* * True, if reports include fragmented high resolution coords, with * high-order X and then Y bytes following the pressure field. * Only valid if "id" is not zero. */ bool fragmented_hires; }; /* * Parameters of frame control inputs of a tablet interface. * * Must use declarative (descriptive) language, not imperative, to simplify * understanding and maintain consistency. * * Noop (preserving functionality) when filled with zeroes. */ struct uclogic_params_frame { /* * Pointer to report descriptor describing the inputs. * Allocated with kmalloc. */ __u8 *desc_ptr; /* * Size of the report descriptor. * Only valid, if "desc_ptr" is not NULL. */ unsigned int desc_size; /* * Report ID, if reports should be tweaked, zero if not. */ unsigned int id; /* * Number of the least-significant bit of the 2-bit state of a rotary * encoder, in the report. Cannot point to a 2-bit field crossing a * byte boundary. Zero if not present. Only valid if "id" is not zero. */ unsigned int re_lsb; /* * Offset of the Wacom-style device ID byte in the report, to be set * to pad device ID (0xf), for compatibility with Wacom drivers. Zero * if no changes to the report should be made. Only valid if "id" is * not zero. */ unsigned int dev_id_byte; }; /* * Tablet interface report parameters. * * Must use declarative (descriptive) language, not imperative, to simplify * understanding and maintain consistency. * * When filled with zeros represents a "noop" configuration - passes all * reports unchanged and lets the generic HID driver handle everything. * * The resulting device report descriptor is assembled from all the report * descriptor parts referenced by the structure. No order of assembly should * be assumed. The structure represents original device report descriptor if * all the parts are NULL. */ struct uclogic_params { /* * True if the whole interface is invalid, false otherwise. */ bool invalid; /* * Pointer to the common part of the replacement report descriptor, * allocated with kmalloc. NULL if no common part is needed. * Only valid, if "invalid" is false. */ __u8 *desc_ptr; /* * Size of the common part of the replacement report descriptor. * Only valid, if "desc_ptr" is not NULL. */ unsigned int desc_size; /* * True, if pen usage in report descriptor is invalid, when present. * Only valid, if "invalid" is false. */ bool pen_unused; /* * Pen parameters and optional report descriptor part. * Only valid if "pen_unused" is valid and false. */ struct uclogic_params_pen pen; /* * Frame control parameters and optional report descriptor part. * Only valid, if "invalid" is false. */ struct uclogic_params_frame frame; /* * Bitmask matching frame controls "sub-report" flag in the second * byte of the pen report, or zero if it's not expected. * Only valid if both "pen" and "frame" are valid, and "frame.id" is * not zero. */ __u8 pen_frame_flag; }; /* Initialize a tablet interface and discover its parameters */ extern int uclogic_params_init(struct uclogic_params *params, struct hid_device *hdev); /* Tablet interface parameters *printf format string */ #define UCLOGIC_PARAMS_FMT_STR \ ".invalid = %s\n" \ ".desc_ptr = %p\n" \ ".desc_size = %u\n" \ ".pen_unused = %s\n" \ ".pen.desc_ptr = %p\n" \ ".pen.desc_size = %u\n" \ ".pen.id = %u\n" \ ".pen.inrange = %s\n" \ ".pen.fragmented_hires = %s\n" \ ".frame.desc_ptr = %p\n" \ ".frame.desc_size = %u\n" \ ".frame.id = %u\n" \ ".frame.re_lsb = %u\n" \ ".frame.dev_id_byte = %u\n" \ ".pen_frame_flag = 0x%02x\n" /* Tablet interface parameters *printf format arguments */ #define UCLOGIC_PARAMS_FMT_ARGS(_params) \ ((_params)->invalid ? "true" : "false"), \ (_params)->desc_ptr, \ (_params)->desc_size, \ ((_params)->pen_unused ? "true" : "false"), \ (_params)->pen.desc_ptr, \ (_params)->pen.desc_size, \ (_params)->pen.id, \ uclogic_params_pen_inrange_to_str((_params)->pen.inrange), \ ((_params)->pen.fragmented_hires ? "true" : "false"), \ (_params)->frame.desc_ptr, \ (_params)->frame.desc_size, \ (_params)->frame.id, \ (_params)->frame.re_lsb, \ (_params)->frame.dev_id_byte, \ (_params)->pen_frame_flag /* Get a replacement report descriptor for a tablet's interface. */ extern int uclogic_params_get_desc(const struct uclogic_params *params, __u8 **pdesc, unsigned int *psize); /* Free resources used by tablet interface's parameters */ extern void uclogic_params_cleanup(struct uclogic_params *params); #endif /* _HID_UCLOGIC_PARAMS_H */