root/drivers/hid/hid-holtekff.c

DEFINITIONS

1. holtekff_send
2. holtekff_play
3. holtekff_init
4. holtekff_init
5. holtek_probe

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Force feedback support for Holtek On Line Grip based gamepads
   4  *
   5  *  These include at least a Brazilian "Clone Joypad Super Power Fire"
   6  *  which uses vendor ID 0x1241 and identifies as "HOLTEK On Line Grip".
   7  *
   8  *  Copyright (c) 2011 Anssi Hannula <anssi.hannula@iki.fi>
   9  */
  10 
  11 /*
  12  */
  13 
  14 #include <linux/hid.h>
  15 #include <linux/input.h>
  16 #include <linux/module.h>
  17 #include <linux/slab.h>
  18 
  19 #include "hid-ids.h"
  20 
  21 #ifdef CONFIG_HOLTEK_FF
  22 
  23 /*
  24  * These commands and parameters are currently known:
  25  *
  26  * byte 0: command id:
  27  *      01  set effect parameters
  28  *      02  play specified effect
  29  *      03  stop specified effect
  30  *      04  stop all effects
  31  *      06  stop all effects
  32  *      (the difference between 04 and 06 isn't known; win driver
  33  *       sends 06,04 on application init, and 06 otherwise)
  34  * 
  35  * Commands 01 and 02 need to be sent as pairs, i.e. you need to send 01
  36  * before each 02.
  37  *
  38  * The rest of the bytes are parameters. Command 01 takes all of them, and
  39  * commands 02,03 take only the effect id.
  40  *
  41  * byte 1:
  42  *      bits 0-3: effect id:
  43  *              1: very strong rumble
  44  *              2: periodic rumble, short intervals
  45  *              3: very strong rumble
  46  *              4: periodic rumble, long intervals
  47  *              5: weak periodic rumble, long intervals
  48  *              6: weak periodic rumble, short intervals
  49  *              7: periodic rumble, short intervals
  50  *              8: strong periodic rumble, short intervals
  51  *              9: very strong rumble
  52  *              a: causes an error
  53  *              b: very strong periodic rumble, very short intervals
  54  *              c-f: nothing
  55  *      bit 6: right (weak) motor enabled
  56  *      bit 7: left (strong) motor enabled
  57  *
  58  * bytes 2-3:  time in milliseconds, big-endian
  59  * bytes 5-6:  unknown (win driver seems to use at least 10e0 with effect 1
  60  *                     and 0014 with effect 6)
  61  * byte 7:
  62  *      bits 0-3: effect magnitude
  63  */
  64 
  65 #define HOLTEKFF_MSG_LENGTH     7
  66 
  67 static const u8 start_effect_1[] = { 0x02, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00 };
  68 static const u8 stop_all4[] =      { 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
  69 static const u8 stop_all6[] =      { 0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
  70 
  71 struct holtekff_device {
  72         struct hid_field *field;
  73 };
  74 
  75 static void holtekff_send(struct holtekff_device *holtekff,
  76                           struct hid_device *hid,
  77                           const u8 data[HOLTEKFF_MSG_LENGTH])
  78 {
  79         int i;
  80 
  81         for (i = 0; i < HOLTEKFF_MSG_LENGTH; i++) {
  82                 holtekff->field->value[i] = data[i];
  83         }
  84 
  85         dbg_hid("sending %7ph\n", data);
  86 
  87         hid_hw_request(hid, holtekff->field->report, HID_REQ_SET_REPORT);
  88 }
  89 
  90 static int holtekff_play(struct input_dev *dev, void *data,
  91                          struct ff_effect *effect)
  92 {
  93         struct hid_device *hid = input_get_drvdata(dev);
  94         struct holtekff_device *holtekff = data;
  95         int left, right;
  96         /* effect type 1, length 65535 msec */
  97         u8 buf[HOLTEKFF_MSG_LENGTH] =
  98                 { 0x01, 0x01, 0xff, 0xff, 0x10, 0xe0, 0x00 };
  99 
 100         left = effect->u.rumble.strong_magnitude;
 101         right = effect->u.rumble.weak_magnitude;
 102         dbg_hid("called with 0x%04x 0x%04x\n", left, right);
 103 
 104         if (!left && !right) {
 105                 holtekff_send(holtekff, hid, stop_all6);
 106                 return 0;
 107         }
 108 
 109         if (left)
 110                 buf[1] |= 0x80;
 111         if (right)
 112                 buf[1] |= 0x40;
 113 
 114         /* The device takes a single magnitude, so we just sum them up. */
 115         buf[6] = min(0xf, (left >> 12) + (right >> 12));
 116 
 117         holtekff_send(holtekff, hid, buf);
 118         holtekff_send(holtekff, hid, start_effect_1);
 119 
 120         return 0;
 121 }
 122 
 123 static int holtekff_init(struct hid_device *hid)
 124 {
 125         struct holtekff_device *holtekff;
 126         struct hid_report *report;
 127         struct hid_input *hidinput;
 128         struct list_head *report_list =
 129                         &hid->report_enum[HID_OUTPUT_REPORT].report_list;
 130         struct input_dev *dev;
 131         int error;
 132 
 133         if (list_empty(&hid->inputs)) {
 134                 hid_err(hid, "no inputs found\n");
 135                 return -ENODEV;
 136         }
 137         hidinput = list_entry(hid->inputs.next, struct hid_input, list);
 138         dev = hidinput->input;
 139 
 140         if (list_empty(report_list)) {
 141                 hid_err(hid, "no output report found\n");
 142                 return -ENODEV;
 143         }
 144 
 145         report = list_entry(report_list->next, struct hid_report, list);
 146 
 147         if (report->maxfield < 1 || report->field[0]->report_count != 7) {
 148                 hid_err(hid, "unexpected output report layout\n");
 149                 return -ENODEV;
 150         }
 151 
 152         holtekff = kzalloc(sizeof(*holtekff), GFP_KERNEL);
 153         if (!holtekff)
 154                 return -ENOMEM;
 155 
 156         set_bit(FF_RUMBLE, dev->ffbit);
 157 
 158         holtekff->field = report->field[0];
 159 
 160         /* initialize the same way as win driver does */
 161         holtekff_send(holtekff, hid, stop_all4);
 162         holtekff_send(holtekff, hid, stop_all6);
 163 
 164         error = input_ff_create_memless(dev, holtekff, holtekff_play);
 165         if (error) {
 166                 kfree(holtekff);
 167                 return error;
 168         }
 169 
 170         hid_info(hid, "Force feedback for Holtek On Line Grip based devices by Anssi Hannula <anssi.hannula@iki.fi>\n");
 171 
 172         return 0;
 173 }
 174 #else
 175 static inline int holtekff_init(struct hid_device *hid)
 176 {
 177         return 0;
 178 }
 179 #endif
 180 
 181 static int holtek_probe(struct hid_device *hdev, const struct hid_device_id *id)
 182 {
 183         int ret;
 184 
 185         ret = hid_parse(hdev);
 186         if (ret) {
 187                 hid_err(hdev, "parse failed\n");
 188                 goto err;
 189         }
 190 
 191         ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
 192         if (ret) {
 193                 hid_err(hdev, "hw start failed\n");
 194                 goto err;
 195         }
 196 
 197         holtekff_init(hdev);
 198 
 199         return 0;
 200 err:
 201         return ret;
 202 }
 203 
 204 static const struct hid_device_id holtek_devices[] = {
 205         { HID_USB_DEVICE(USB_VENDOR_ID_HOLTEK, USB_DEVICE_ID_HOLTEK_ON_LINE_GRIP) },
 206         { }
 207 };
 208 MODULE_DEVICE_TABLE(hid, holtek_devices);
 209 
 210 static struct hid_driver holtek_driver = {
 211         .name = "holtek",
 212         .id_table = holtek_devices,
 213         .probe = holtek_probe,
 214 };
 215 module_hid_driver(holtek_driver);
 216 
 217 MODULE_LICENSE("GPL");
 218 MODULE_AUTHOR("Anssi Hannula <anssi.hannula@iki.fi>");
 219 MODULE_DESCRIPTION("Force feedback support for Holtek On Line Grip based devices");