drivers/input/joystick/iforce/iforce-packets.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Copyright (c) 2000-2002 Vojtech Pavlik <vojtech@ucw.cz>
   4  *  Copyright (c) 2001-2002, 2007 Johann Deneux <johann.deneux@gmail.com>
   5  *
   6  *  USB/RS232 I-Force joysticks and wheels.
   7  */
   8
   9 #include <linux/unaligned.h>
  10 #include "iforce.h"
  11
  12 static struct {
  13         __s32 x;
  14         __s32 y;
  15 } iforce_hat_to_axis[16] = {{ 0,-1}, { 1,-1}, { 1, 0}, { 1, 1}, { 0, 1}, {-1, 1}, {-1, 0}, {-1,-1}};
  16
  17
  18 void iforce_dump_packet(struct iforce *iforce, char *msg, u16 cmd, unsigned char *data)
  19 {
  20         dev_dbg(iforce->dev->dev.parent, "%s %s cmd = %04x, data = %*ph\n",
  21                 __func__, msg, cmd, LO(cmd), data);
  22 }
  23
  24 /*
  25  * Send a packet of bytes to the device
  26  */
  27 int iforce_send_packet(struct iforce *iforce, u16 cmd, unsigned char* data)
  28 {
  29         /* Copy data to buffer */
  30         int n = LO(cmd);
  31         int c;
  32         int empty;
  33         int head, tail;
  34
  35 /*
  36  * Update head and tail of xmit buffer
  37  */
  38         scoped_guard(spinlock_irqsave, &iforce->xmit_lock) {
  39                 head = iforce->xmit.head;
  40                 tail = iforce->xmit.tail;
  41
  42                 if (CIRC_SPACE(head, tail, XMIT_SIZE) < n + 2) {
  43                         dev_warn(&iforce->dev->dev,
  44                                  "not enough space in xmit buffer to send new packet\n");
  45                         return -1;
  46                 }
  47
  48                 empty = head == tail;
  49                 XMIT_INC(iforce->xmit.head, n + 2);
  50
  51 /*
  52  * Store packet in xmit buffer
  53  */
  54                 iforce->xmit.buf[head] = HI(cmd);
  55                 XMIT_INC(head, 1);
  56                 iforce->xmit.buf[head] = LO(cmd);
  57                 XMIT_INC(head, 1);
  58
  59                 c = CIRC_SPACE_TO_END(head, tail, XMIT_SIZE);
  60                 if (n < c)
  61                         c = n;
  62
  63                 memcpy(&iforce->xmit.buf[head], data, c);
  64                 if (n != c)
  65                         memcpy(&iforce->xmit.buf[0], data + c, n - c);
  66
  67                 XMIT_INC(head, n);
  68         }
  69
  70 /*
  71  * If necessary, start the transmission
  72  */
  73         if (empty)
  74                 iforce->xport_ops->xmit(iforce);
  75
  76         return 0;
  77 }
  78 EXPORT_SYMBOL(iforce_send_packet);
  79
  80 /* Start or stop an effect */
  81 int iforce_control_playback(struct iforce* iforce, u16 id, unsigned int value)
  82 {
  83         unsigned char data[3];
  84
  85         data[0] = LO(id);
  86         data[1] = (value > 0) ? ((value > 1) ? 0x41 : 0x01) : 0;
  87         data[2] = LO(value);
  88         return iforce_send_packet(iforce, FF_CMD_PLAY, data);
  89 }
  90
  91 /* Mark an effect that was being updated as ready. That means it can be updated
  92  * again */
  93 static int mark_core_as_ready(struct iforce *iforce, unsigned short addr)
  94 {
  95         int i;
  96
  97         if (!iforce->dev->ff)
  98                 return 0;
  99
 100         for (i = 0; i < iforce->dev->ff->max_effects; ++i) {
 101                 if (test_bit(FF_CORE_IS_USED, iforce->core_effects[i].flags) &&
 102                     (iforce->core_effects[i].mod1_chunk.start == addr ||
 103                      iforce->core_effects[i].mod2_chunk.start == addr)) {
 104                         clear_bit(FF_CORE_UPDATE, iforce->core_effects[i].flags);
 105                         return 0;
 106                 }
 107         }
 108         dev_warn(&iforce->dev->dev, "unused effect %04x updated !!!\n", addr);
 109         return -1;
 110 }
 111
 112 static void iforce_report_hats_buttons(struct iforce *iforce, u8 *data)
 113 {
 114         struct input_dev *dev = iforce->dev;
 115         int i;
 116
 117         input_report_abs(dev, ABS_HAT0X, iforce_hat_to_axis[data[6] >> 4].x);
 118         input_report_abs(dev, ABS_HAT0Y, iforce_hat_to_axis[data[6] >> 4].y);
 119
 120         for (i = 0; iforce->type->btn[i] >= 0; i++)
 121                 input_report_key(dev, iforce->type->btn[i],
 122                                  data[(i >> 3) + 5] & (1 << (i & 7)));
 123
 124         /* If there are untouched bits left, interpret them as the second hat */
 125         if (i <= 8) {
 126                 u8 btns = data[6];
 127
 128                 if (test_bit(ABS_HAT1X, dev->absbit)) {
 129                         if (btns & BIT(3))
 130                                 input_report_abs(dev, ABS_HAT1X, -1);
 131                         else if (btns & BIT(1))
 132                                 input_report_abs(dev, ABS_HAT1X, 1);
 133                         else
 134                                 input_report_abs(dev, ABS_HAT1X, 0);
 135                 }
 136
 137                 if (test_bit(ABS_HAT1Y, dev->absbit)) {
 138                         if (btns & BIT(0))
 139                                 input_report_abs(dev, ABS_HAT1Y, -1);
 140                         else if (btns & BIT(2))
 141                                 input_report_abs(dev, ABS_HAT1Y, 1);
 142                         else
 143                                 input_report_abs(dev, ABS_HAT1Y, 0);
 144                 }
 145         }
 146 }
 147
 148 void iforce_process_packet(struct iforce *iforce,
 149                            u8 packet_id, u8 *data, size_t len)
 150 {
 151         struct input_dev *dev = iforce->dev;
 152         int i, j;
 153
 154         switch (packet_id) {
 155
 156         case 0x01:      /* joystick position data */
 157                 input_report_abs(dev, ABS_X,
 158                                  (__s16) get_unaligned_le16(data));
 159                 input_report_abs(dev, ABS_Y,
 160                                  (__s16) get_unaligned_le16(data + 2));
 161                 input_report_abs(dev, ABS_THROTTLE, 255 - data[4]);
 162
 163                 if (len >= 8 && test_bit(ABS_RUDDER ,dev->absbit))
 164                         input_report_abs(dev, ABS_RUDDER, (__s8)data[7]);
 165
 166                 iforce_report_hats_buttons(iforce, data);
 167
 168                 input_sync(dev);
 169                 break;
 170
 171         case 0x03:      /* wheel position data */
 172                 input_report_abs(dev, ABS_WHEEL,
 173                                  (__s16) get_unaligned_le16(data));
 174                 input_report_abs(dev, ABS_GAS,   255 - data[2]);
 175                 input_report_abs(dev, ABS_BRAKE, 255 - data[3]);
 176
 177                 iforce_report_hats_buttons(iforce, data);
 178
 179                 input_sync(dev);
 180                 break;
 181
 182         case 0x02:      /* status report */
 183                 input_report_key(dev, BTN_DEAD, data[0] & 0x02);
 184                 input_sync(dev);
 185
 186                 /* Check if an effect was just started or stopped */
 187                 i = data[1] & 0x7f;
 188                 if (data[1] & 0x80) {
 189                         if (!test_and_set_bit(FF_CORE_IS_PLAYED, iforce->core_effects[i].flags)) {
 190                                 /* Report play event */
 191                                 input_report_ff_status(dev, i, FF_STATUS_PLAYING);
 192                         }
 193                 } else if (test_and_clear_bit(FF_CORE_IS_PLAYED, iforce->core_effects[i].flags)) {
 194                         /* Report stop event */
 195                         input_report_ff_status(dev, i, FF_STATUS_STOPPED);
 196                 }
 197
 198                 for (j = 3; j < len; j += 2)
 199                         mark_core_as_ready(iforce, get_unaligned_le16(data + j));
 200
 201                 break;
 202         }
 203 }
 204 EXPORT_SYMBOL(iforce_process_packet);