hw/lm832x.c

   1 /*
   2  * National Semiconductor LM8322/8323 GPIO keyboard & PWM chips.
   3  *
   4  * Copyright (C) 2008 Nokia Corporation
   5  * Written by Andrzej Zaborowski <andrew@openedhand.com>
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License as
   9  * published by the Free Software Foundation; either version 2 or
  10  * (at your option) version 3 of the License.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "hw.h"
  22 #include "i2c.h"
  23 #include "qemu-timer.h"
  24 #include "console.h"
  25
  26 typedef struct {
  27     i2c_slave i2c;
  28     uint8_t i2c_dir;
  29     uint8_t i2c_cycle;
  30     uint8_t reg;
  31
  32     qemu_irq nirq;
  33     uint16_t model;
  34
  35     struct {
  36         qemu_irq out[2];
  37         int in[2][2];
  38     } mux;
  39
  40     uint8_t config;
  41     uint8_t status;
  42     uint8_t acttime;
  43     uint8_t error;
  44     uint8_t clock;
  45
  46     struct {
  47         uint16_t pull;
  48         uint16_t mask;
  49         uint16_t dir;
  50         uint16_t level;
  51         qemu_irq out[16];
  52     } gpio;
  53
  54     struct {
  55         uint8_t dbnctime;
  56         uint8_t size;
  57         uint8_t start;
  58         uint8_t len;
  59         uint8_t fifo[16];
  60     } kbd;
  61
  62     struct {
  63         uint16_t file[256];
  64         uint8_t faddr;
  65         uint8_t addr[3];
  66         QEMUTimer *tm[3];
  67     } pwm;
  68 } LM823KbdState;
  69
  70 #define INT_KEYPAD              (1 << 0)
  71 #define INT_ERROR               (1 << 3)
  72 #define INT_NOINIT              (1 << 4)
  73 #define INT_PWMEND(n)           (1 << (5 + n))
  74
  75 #define ERR_BADPAR              (1 << 0)
  76 #define ERR_CMDUNK              (1 << 1)
  77 #define ERR_KEYOVR              (1 << 2)
  78 #define ERR_FIFOOVR             (1 << 6)
  79
  80 static void lm_kbd_irq_update(LM823KbdState *s)
  81 {
  82     qemu_set_irq(s->nirq, !s->status);
  83 }
  84
  85 static void lm_kbd_gpio_update(LM823KbdState *s)
  86 {
  87 }
  88
  89 static void lm_kbd_reset(LM823KbdState *s)
  90 {
  91     s->config = 0x80;
  92     s->status = INT_NOINIT;
  93     s->acttime = 125;
  94     s->kbd.dbnctime = 3;
  95     s->kbd.size = 0x33;
  96     s->clock = 0x08;
  97
  98     lm_kbd_irq_update(s);
  99     lm_kbd_gpio_update(s);
 100 }
 101
 102 static void lm_kbd_error(LM823KbdState *s, int err)
 103 {
 104     s->error |= err;
 105     s->status |= INT_ERROR;
 106     lm_kbd_irq_update(s);
 107 }
 108
 109 static void lm_kbd_pwm_tick(LM823KbdState *s, int line)
 110 {
 111 }
 112
 113 static void lm_kbd_pwm_start(LM823KbdState *s, int line)
 114 {
 115     lm_kbd_pwm_tick(s, line);
 116 }
 117
 118 static void lm_kbd_pwm0_tick(void *opaque)
 119 {
 120     lm_kbd_pwm_tick(opaque, 0);
 121 }
 122 static void lm_kbd_pwm1_tick(void *opaque)
 123 {
 124     lm_kbd_pwm_tick(opaque, 1);
 125 }
 126 static void lm_kbd_pwm2_tick(void *opaque)
 127 {
 128     lm_kbd_pwm_tick(opaque, 2);
 129 }
 130
 131 enum {
 132     LM832x_CMD_READ_ID          = 0x80, /* Read chip ID. */
 133     LM832x_CMD_WRITE_CFG        = 0x81, /* Set configuration item. */
 134     LM832x_CMD_READ_INT         = 0x82, /* Get interrupt status. */
 135     LM832x_CMD_RESET            = 0x83, /* Reset, same as external one */
 136     LM823x_CMD_WRITE_PULL_DOWN  = 0x84, /* Select GPIO pull-up/down. */
 137     LM832x_CMD_WRITE_PORT_SEL   = 0x85, /* Select GPIO in/out. */
 138     LM832x_CMD_WRITE_PORT_STATE = 0x86, /* Set GPIO pull-up/down. */
 139     LM832x_CMD_READ_PORT_SEL    = 0x87, /* Get GPIO in/out. */
 140     LM832x_CMD_READ_PORT_STATE  = 0x88, /* Get GPIO pull-up/down. */
 141     LM832x_CMD_READ_FIFO        = 0x89, /* Read byte from FIFO. */
 142     LM832x_CMD_RPT_READ_FIFO    = 0x8a, /* Read FIFO (no increment). */
 143     LM832x_CMD_SET_ACTIVE       = 0x8b, /* Set active time. */
 144     LM832x_CMD_READ_ERROR       = 0x8c, /* Get error status. */
 145     LM832x_CMD_READ_ROTATOR     = 0x8e, /* Read rotator status. */
 146     LM832x_CMD_SET_DEBOUNCE     = 0x8f, /* Set debouncing time. */
 147     LM832x_CMD_SET_KEY_SIZE     = 0x90, /* Set keypad size. */
 148     LM832x_CMD_READ_KEY_SIZE    = 0x91, /* Get keypad size. */
 149     LM832x_CMD_READ_CFG         = 0x92, /* Get configuration item. */
 150     LM832x_CMD_WRITE_CLOCK      = 0x93, /* Set clock config. */
 151     LM832x_CMD_READ_CLOCK       = 0x94, /* Get clock config. */
 152     LM832x_CMD_PWM_WRITE        = 0x95, /* Write PWM script. */
 153     LM832x_CMD_PWM_START        = 0x96, /* Start PWM engine. */
 154     LM832x_CMD_PWM_STOP         = 0x97, /* Stop PWM engine. */
 155     LM832x_GENERAL_ERROR        = 0xff, /* There was one error.
 156                                            Previously was represented by -1
 157                                            This is not a command */
 158 };
 159
 160 #define LM832x_MAX_KPX          8
 161 #define LM832x_MAX_KPY          12
 162
 163 static uint8_t lm_kbd_read(LM823KbdState *s, int reg, int byte)
 164 {
 165     int ret;
 166
 167     switch (reg) {
 168     case LM832x_CMD_READ_ID:
 169         ret = 0x0400;
 170         break;
 171
 172     case LM832x_CMD_READ_INT:
 173         ret = s->status;
 174         if (!(s->status & INT_NOINIT)) {
 175             s->status = 0;
 176             lm_kbd_irq_update(s);
 177         }
 178         break;
 179
 180     case LM832x_CMD_READ_PORT_SEL:
 181         ret = s->gpio.dir;
 182         break;
 183     case LM832x_CMD_READ_PORT_STATE:
 184         ret = s->gpio.mask;
 185         break;
 186
 187     case LM832x_CMD_READ_FIFO:
 188         if (s->kbd.len <= 1)
 189             return 0x00;
 190
 191         /* Example response from the two commands after a INT_KEYPAD
 192          * interrupt caused by the key 0x3c being pressed:
 193          * RPT_READ_FIFO: 55 bc 00 4e ff 0a 50 08 00 29 d9 08 01 c9 01
 194          *     READ_FIFO: bc 00 00 4e ff 0a 50 08 00 29 d9 08 01 c9 01
 195          * RPT_READ_FIFO: bc 00 00 4e ff 0a 50 08 00 29 d9 08 01 c9 01
 196          *
 197          * 55 is the code of the key release event serviced in the previous
 198          * interrupt handling.
 199          *
 200          * TODO: find out whether the FIFO is advanced a single character
 201          * before reading every byte or the whole size of the FIFO at the
 202          * last LM832x_CMD_READ_FIFO.  This affects LM832x_CMD_RPT_READ_FIFO
 203          * output in cases where there are more than one event in the FIFO.
 204          * Assume 0xbc and 0x3c events are in the FIFO:
 205          * RPT_READ_FIFO: 55 bc 3c 00 4e ff 0a 50 08 00 29 d9 08 01 c9
 206          *     READ_FIFO: bc 3c 00 00 4e ff 0a 50 08 00 29 d9 08 01 c9
 207          * Does RPT_READ_FIFO now return 0xbc and 0x3c or only 0x3c?
 208          */
 209         s->kbd.start ++;
 210         s->kbd.start &= sizeof(s->kbd.fifo) - 1;
 211         s->kbd.len --;
 212
 213         return s->kbd.fifo[s->kbd.start];
 214     case LM832x_CMD_RPT_READ_FIFO:
 215         if (byte >= s->kbd.len)
 216             return 0x00;
 217
 218         return s->kbd.fifo[(s->kbd.start + byte) & (sizeof(s->kbd.fifo) - 1)];
 219
 220     case LM832x_CMD_READ_ERROR:
 221         return s->error;
 222
 223     case LM832x_CMD_READ_ROTATOR:
 224         return 0;
 225
 226     case LM832x_CMD_READ_KEY_SIZE:
 227         return s->kbd.size;
 228
 229     case LM832x_CMD_READ_CFG:
 230         return s->config & 0xf;
 231
 232     case LM832x_CMD_READ_CLOCK:
 233         return (s->clock & 0xfc) | 2;
 234
 235     default:
 236         lm_kbd_error(s, ERR_CMDUNK);
 237         fprintf(stderr, "%s: unknown command %02x\n", __FUNCTION__, reg);
 238         return 0x00;
 239     }
 240
 241     return ret >> (byte << 3);
 242 }
 243
 244 static void lm_kbd_write(LM823KbdState *s, int reg, int byte, uint8_t value)
 245 {
 246     switch (reg) {
 247     case LM832x_CMD_WRITE_CFG:
 248         s->config = value;
 249         /* This must be done whenever s->mux.in is updated (never).  */
 250         if ((s->config >> 1) & 1)                       /* MUX1EN */
 251             qemu_set_irq(s->mux.out[0], s->mux.in[0][(s->config >> 0) & 1]);
 252         if ((s->config >> 3) & 1)                       /* MUX2EN */
 253             qemu_set_irq(s->mux.out[0], s->mux.in[0][(s->config >> 2) & 1]);
 254         /* TODO: check that this is issued only following the chip reset
 255          * and not in the middle of operation and that it is followed by
 256          * the GPIO ports re-resablishing through WRITE_PORT_SEL and
 257          * WRITE_PORT_STATE (using a timer perhaps) and otherwise output
 258          * warnings.  */
 259         s->status = 0;
 260         lm_kbd_irq_update(s);
 261         s->kbd.len = 0;
 262         s->kbd.start = 0;
 263         s->reg = LM832x_GENERAL_ERROR;
 264         break;
 265
 266     case LM832x_CMD_RESET:
 267         if (value == 0xaa)
 268             lm_kbd_reset(s);
 269         else
 270             lm_kbd_error(s, ERR_BADPAR);
 271         s->reg = LM832x_GENERAL_ERROR;
 272         break;
 273
 274     case LM823x_CMD_WRITE_PULL_DOWN:
 275         if (!byte)
 276             s->gpio.pull = value;
 277         else {
 278             s->gpio.pull |= value << 8;
 279             lm_kbd_gpio_update(s);
 280             s->reg = LM832x_GENERAL_ERROR;
 281         }
 282         break;
 283     case LM832x_CMD_WRITE_PORT_SEL:
 284         if (!byte)
 285             s->gpio.dir = value;
 286         else {
 287             s->gpio.dir |= value << 8;
 288             lm_kbd_gpio_update(s);
 289             s->reg = LM832x_GENERAL_ERROR;
 290         }
 291         break;
 292     case LM832x_CMD_WRITE_PORT_STATE:
 293         if (!byte)
 294             s->gpio.mask = value;
 295         else {
 296             s->gpio.mask |= value << 8;
 297             lm_kbd_gpio_update(s);
 298             s->reg = LM832x_GENERAL_ERROR;
 299         }
 300         break;
 301
 302     case LM832x_CMD_SET_ACTIVE:
 303         s->acttime = value;
 304         s->reg = LM832x_GENERAL_ERROR;
 305         break;
 306
 307     case LM832x_CMD_SET_DEBOUNCE:
 308         s->kbd.dbnctime = value;
 309         s->reg = LM832x_GENERAL_ERROR;
 310         if (!value)
 311             lm_kbd_error(s, ERR_BADPAR);
 312         break;
 313
 314     case LM832x_CMD_SET_KEY_SIZE:
 315         s->kbd.size = value;
 316         s->reg = LM832x_GENERAL_ERROR;
 317         if (
 318                         (value & 0xf) < 3 || (value & 0xf) > LM832x_MAX_KPY ||
 319                         (value >> 4) < 3 || (value >> 4) > LM832x_MAX_KPX)
 320             lm_kbd_error(s, ERR_BADPAR);
 321         break;
 322
 323     case LM832x_CMD_WRITE_CLOCK:
 324         s->clock = value;
 325         s->reg = LM832x_GENERAL_ERROR;
 326         if ((value & 3) && (value & 3) != 3) {
 327             lm_kbd_error(s, ERR_BADPAR);
 328             fprintf(stderr, "%s: invalid clock setting in RCPWM\n",
 329                             __FUNCTION__);
 330         }
 331         /* TODO: Validate that the command is only issued once */
 332         break;
 333
 334     case LM832x_CMD_PWM_WRITE:
 335         if (byte == 0) {
 336             if (!(value & 3) || (value >> 2) > 59) {
 337                 lm_kbd_error(s, ERR_BADPAR);
 338                 s->reg = LM832x_GENERAL_ERROR;
 339                 break;
 340             }
 341
 342             s->pwm.faddr = value;
 343             s->pwm.file[s->pwm.faddr] = 0;
 344         } else if (byte == 1) {
 345             s->pwm.file[s->pwm.faddr] |= value << 8;
 346         } else if (byte == 2) {
 347             s->pwm.file[s->pwm.faddr] |= value << 0;
 348             s->reg = LM832x_GENERAL_ERROR;
 349         }
 350         break;
 351     case LM832x_CMD_PWM_START:
 352         s->reg = LM832x_GENERAL_ERROR;
 353         if (!(value & 3) || (value >> 2) > 59) {
 354             lm_kbd_error(s, ERR_BADPAR);
 355             break;
 356         }
 357
 358         s->pwm.addr[(value & 3) - 1] = value >> 2;
 359         lm_kbd_pwm_start(s, (value & 3) - 1);
 360         break;
 361     case LM832x_CMD_PWM_STOP:
 362         s->reg = LM832x_GENERAL_ERROR;
 363         if (!(value & 3)) {
 364             lm_kbd_error(s, ERR_BADPAR);
 365             break;
 366         }
 367
 368         qemu_del_timer(s->pwm.tm[(value & 3) - 1]);
 369         break;
 370
 371     case LM832x_GENERAL_ERROR:
 372         lm_kbd_error(s, ERR_BADPAR);
 373         break;
 374     default:
 375         lm_kbd_error(s, ERR_CMDUNK);
 376         fprintf(stderr, "%s: unknown command %02x\n", __FUNCTION__, reg);
 377         break;
 378     }
 379 }
 380
 381 static void lm_i2c_event(i2c_slave *i2c, enum i2c_event event)
 382 {
 383     LM823KbdState *s = FROM_I2C_SLAVE(LM823KbdState, i2c);
 384
 385     switch (event) {
 386     case I2C_START_RECV:
 387     case I2C_START_SEND:
 388         s->i2c_cycle = 0;
 389         s->i2c_dir = (event == I2C_START_SEND);
 390         break;
 391
 392     default:
 393         break;
 394     }
 395 }
 396
 397 static int lm_i2c_rx(i2c_slave *i2c)
 398 {
 399     LM823KbdState *s = FROM_I2C_SLAVE(LM823KbdState, i2c);
 400
 401     return lm_kbd_read(s, s->reg, s->i2c_cycle ++);
 402 }
 403
 404 static int lm_i2c_tx(i2c_slave *i2c, uint8_t data)
 405 {
 406     LM823KbdState *s = (LM823KbdState *) i2c;
 407
 408     if (!s->i2c_cycle)
 409         s->reg = data;
 410     else
 411         lm_kbd_write(s, s->reg, s->i2c_cycle - 1, data);
 412     s->i2c_cycle ++;
 413
 414     return 0;
 415 }
 416
 417 static int lm_kbd_post_load(void *opaque, int version_id)
 418 {
 419     LM823KbdState *s = opaque;
 420
 421     lm_kbd_irq_update(s);
 422     lm_kbd_gpio_update(s);
 423
 424     return 0;
 425 }
 426
 427 static const VMStateDescription vmstate_lm_kbd = {
 428     .name = "LM8323",
 429     .version_id = 0,
 430     .minimum_version_id = 0,
 431     .minimum_version_id_old = 0,
 432     .post_load = lm_kbd_post_load,
 433     .fields      = (VMStateField []) {
 434         VMSTATE_I2C_SLAVE(i2c, LM823KbdState),
 435         VMSTATE_UINT8(i2c_dir, LM823KbdState),
 436         VMSTATE_UINT8(i2c_cycle, LM823KbdState),
 437         VMSTATE_UINT8(reg, LM823KbdState),
 438         VMSTATE_UINT8(config, LM823KbdState),
 439         VMSTATE_UINT8(status, LM823KbdState),
 440         VMSTATE_UINT8(acttime, LM823KbdState),
 441         VMSTATE_UINT8(error, LM823KbdState),
 442         VMSTATE_UINT8(clock, LM823KbdState),
 443         VMSTATE_UINT16(gpio.pull, LM823KbdState),
 444         VMSTATE_UINT16(gpio.mask, LM823KbdState),
 445         VMSTATE_UINT16(gpio.dir, LM823KbdState),
 446         VMSTATE_UINT16(gpio.level, LM823KbdState),
 447         VMSTATE_UINT8(kbd.dbnctime, LM823KbdState),
 448         VMSTATE_UINT8(kbd.size, LM823KbdState),
 449         VMSTATE_UINT8(kbd.start, LM823KbdState),
 450         VMSTATE_UINT8(kbd.len, LM823KbdState),
 451         VMSTATE_BUFFER(kbd.fifo, LM823KbdState),
 452         VMSTATE_UINT16_ARRAY(pwm.file, LM823KbdState, 256),
 453         VMSTATE_UINT8(pwm.faddr, LM823KbdState),
 454         VMSTATE_BUFFER(pwm.addr, LM823KbdState),
 455         VMSTATE_TIMER_ARRAY(pwm.tm, LM823KbdState, 3),
 456         VMSTATE_END_OF_LIST()
 457     }
 458 };
 459
 460
 461 static int lm8323_init(i2c_slave *i2c)
 462 {
 463     LM823KbdState *s = FROM_I2C_SLAVE(LM823KbdState, i2c);
 464
 465     s->model = 0x8323;
 466     s->pwm.tm[0] = qemu_new_timer_ns(vm_clock, lm_kbd_pwm0_tick, s);
 467     s->pwm.tm[1] = qemu_new_timer_ns(vm_clock, lm_kbd_pwm1_tick, s);
 468     s->pwm.tm[2] = qemu_new_timer_ns(vm_clock, lm_kbd_pwm2_tick, s);
 469     qdev_init_gpio_out(&i2c->qdev, &s->nirq, 1);
 470
 471     lm_kbd_reset(s);
 472
 473     qemu_register_reset((void *) lm_kbd_reset, s);
 474     return 0;
 475 }
 476
 477 void lm832x_key_event(struct i2c_slave *i2c, int key, int state)
 478 {
 479     LM823KbdState *s = (LM823KbdState *) i2c;
 480
 481     if ((s->status & INT_ERROR) && (s->error & ERR_FIFOOVR))
 482         return;
 483
 484     if (s->kbd.len >= sizeof(s->kbd.fifo)) {
 485         lm_kbd_error(s, ERR_FIFOOVR);
 486         return;
 487     }
 488
 489     s->kbd.fifo[(s->kbd.start + s->kbd.len ++) & (sizeof(s->kbd.fifo) - 1)] =
 490             key | (state << 7);
 491
 492     /* We never set ERR_KEYOVR because we support multiple keys fine.  */
 493     s->status |= INT_KEYPAD;
 494     lm_kbd_irq_update(s);
 495 }
 496
 497 static I2CSlaveInfo lm8323_info = {
 498     .qdev.name = "lm8323",
 499     .qdev.size = sizeof(LM823KbdState),
 500     .qdev.vmsd = &vmstate_lm_kbd,
 501     .init = lm8323_init,
 502     .event = lm_i2c_event,
 503     .recv = lm_i2c_rx,
 504     .send = lm_i2c_tx
 505 };
 506
 507 static void lm832x_register_devices(void)
 508 {
 509     i2c_register_slave(&lm8323_info);
 510 }
 511
 512 device_init(lm832x_register_devices)