diff options
Diffstat (limited to 'drivers/hid/hid-uclogic-params.h')
| -rw-r--r-- | drivers/hid/hid-uclogic-params.h | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/drivers/hid/hid-uclogic-params.h b/drivers/hid/hid-uclogic-params.h new file mode 100644 index 000000000000..ba48b1c7a0e5 --- /dev/null +++ b/drivers/hid/hid-uclogic-params.h @@ -0,0 +1,207 @@ +/* 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 */ |