1 /* 2 * Provides I2C support for Philips PNX010x/PNX4008 boards. 3 * 4 * Authors: Dennis Kovalev <dkovalev@ru.mvista.com> 5 * Vitaly Wool <vwool@ru.mvista.com> 6 * 7 * 2004-2006 (c) MontaVista Software, Inc. This file is licensed under 8 * the terms of the GNU General Public License version 2. This program 9 * is licensed "as is" without any warranty of any kind, whether express 10 * or implied. 11 */ 12 13 #include <linux/module.h> 14 #include <linux/interrupt.h> 15 #include <linux/ioport.h> 16 #include <linux/delay.h> 17 #include <linux/i2c.h> 18 #include <linux/timer.h> 19 #include <linux/completion.h> 20 #include <linux/platform_device.h> 21 #include <linux/i2c-pnx.h> 22 #include <linux/io.h> 23 #include <linux/err.h> 24 #include <linux/clk.h> 25 #include <linux/slab.h> 26 #include <linux/of.h> 27 28 #define I2C_PNX_TIMEOUT_DEFAULT 10 /* msec */ 29 #define I2C_PNX_SPEED_KHZ_DEFAULT 100 30 #define I2C_PNX_REGION_SIZE 0x100 31 32 enum { 33 mstatus_tdi = 0x00000001, 34 mstatus_afi = 0x00000002, 35 mstatus_nai = 0x00000004, 36 mstatus_drmi = 0x00000008, 37 mstatus_active = 0x00000020, 38 mstatus_scl = 0x00000040, 39 mstatus_sda = 0x00000080, 40 mstatus_rff = 0x00000100, 41 mstatus_rfe = 0x00000200, 42 mstatus_tff = 0x00000400, 43 mstatus_tfe = 0x00000800, 44 }; 45 46 enum { 47 mcntrl_tdie = 0x00000001, 48 mcntrl_afie = 0x00000002, 49 mcntrl_naie = 0x00000004, 50 mcntrl_drmie = 0x00000008, 51 mcntrl_drsie = 0x00000010, 52 mcntrl_rffie = 0x00000020, 53 mcntrl_daie = 0x00000040, 54 mcntrl_tffie = 0x00000080, 55 mcntrl_reset = 0x00000100, 56 mcntrl_cdbmode = 0x00000400, 57 }; 58 59 enum { 60 rw_bit = 1 << 0, 61 start_bit = 1 << 8, 62 stop_bit = 1 << 9, 63 }; 64 65 #define I2C_REG_RX(a) ((a)->ioaddr) /* Rx FIFO reg (RO) */ 66 #define I2C_REG_TX(a) ((a)->ioaddr) /* Tx FIFO reg (WO) */ 67 #define I2C_REG_STS(a) ((a)->ioaddr + 0x04) /* Status reg (RO) */ 68 #define I2C_REG_CTL(a) ((a)->ioaddr + 0x08) /* Ctl reg */ 69 #define I2C_REG_CKL(a) ((a)->ioaddr + 0x0c) /* Clock divider low */ 70 #define I2C_REG_CKH(a) ((a)->ioaddr + 0x10) /* Clock divider high */ 71 #define I2C_REG_ADR(a) ((a)->ioaddr + 0x14) /* I2C address */ 72 #define I2C_REG_RFL(a) ((a)->ioaddr + 0x18) /* Rx FIFO level (RO) */ 73 #define I2C_REG_TFL(a) ((a)->ioaddr + 0x1c) /* Tx FIFO level (RO) */ 74 #define I2C_REG_RXB(a) ((a)->ioaddr + 0x20) /* Num of bytes Rx-ed (RO) */ 75 #define I2C_REG_TXB(a) ((a)->ioaddr + 0x24) /* Num of bytes Tx-ed (RO) */ 76 #define I2C_REG_TXS(a) ((a)->ioaddr + 0x28) /* Tx slave FIFO (RO) */ 77 #define I2C_REG_STFL(a) ((a)->ioaddr + 0x2c) /* Tx slave FIFO level (RO) */ 78 79 static inline int wait_timeout(struct i2c_pnx_algo_data *data) 80 { 81 long timeout = data->timeout; 82 while (timeout > 0 && 83 (ioread32(I2C_REG_STS(data)) & mstatus_active)) { 84 mdelay(1); 85 timeout--; 86 } 87 return (timeout <= 0); 88 } 89 90 static inline int wait_reset(struct i2c_pnx_algo_data *data) 91 { 92 long timeout = data->timeout; 93 while (timeout > 0 && 94 (ioread32(I2C_REG_CTL(data)) & mcntrl_reset)) { 95 mdelay(1); 96 timeout--; 97 } 98 return (timeout <= 0); 99 } 100 101 static inline void i2c_pnx_arm_timer(struct i2c_pnx_algo_data *alg_data) 102 { 103 struct timer_list *timer = &alg_data->mif.timer; 104 unsigned long expires = msecs_to_jiffies(alg_data->timeout); 105 106 if (expires <= 1) 107 expires = 2; 108 109 del_timer_sync(timer); 110 111 dev_dbg(&alg_data->adapter.dev, "Timer armed at %lu plus %lu jiffies.\n", 112 jiffies, expires); 113 114 timer->expires = jiffies + expires; 115 timer->data = (unsigned long)alg_data; 116 117 add_timer(timer); 118 } 119 120 /** 121 * i2c_pnx_start - start a device 122 * @slave_addr: slave address 123 * @adap: pointer to adapter structure 124 * 125 * Generate a START signal in the desired mode. 126 */ 127 static int i2c_pnx_start(unsigned char slave_addr, 128 struct i2c_pnx_algo_data *alg_data) 129 { 130 dev_dbg(&alg_data->adapter.dev, "%s(): addr 0x%x mode %d\n", __func__, 131 slave_addr, alg_data->mif.mode); 132 133 /* Check for 7 bit slave addresses only */ 134 if (slave_addr & ~0x7f) { 135 dev_err(&alg_data->adapter.dev, 136 "%s: Invalid slave address %x. Only 7-bit addresses are supported\n", 137 alg_data->adapter.name, slave_addr); 138 return -EINVAL; 139 } 140 141 /* First, make sure bus is idle */ 142 if (wait_timeout(alg_data)) { 143 /* Somebody else is monopolizing the bus */ 144 dev_err(&alg_data->adapter.dev, 145 "%s: Bus busy. Slave addr = %02x, cntrl = %x, stat = %x\n", 146 alg_data->adapter.name, slave_addr, 147 ioread32(I2C_REG_CTL(alg_data)), 148 ioread32(I2C_REG_STS(alg_data))); 149 return -EBUSY; 150 } else if (ioread32(I2C_REG_STS(alg_data)) & mstatus_afi) { 151 /* Sorry, we lost the bus */ 152 dev_err(&alg_data->adapter.dev, 153 "%s: Arbitration failure. Slave addr = %02x\n", 154 alg_data->adapter.name, slave_addr); 155 return -EIO; 156 } 157 158 /* 159 * OK, I2C is enabled and we have the bus. 160 * Clear the current TDI and AFI status flags. 161 */ 162 iowrite32(ioread32(I2C_REG_STS(alg_data)) | mstatus_tdi | mstatus_afi, 163 I2C_REG_STS(alg_data)); 164 165 dev_dbg(&alg_data->adapter.dev, "%s(): sending %#x\n", __func__, 166 (slave_addr << 1) | start_bit | alg_data->mif.mode); 167 168 /* Write the slave address, START bit and R/W bit */ 169 iowrite32((slave_addr << 1) | start_bit | alg_data->mif.mode, 170 I2C_REG_TX(alg_data)); 171 172 dev_dbg(&alg_data->adapter.dev, "%s(): exit\n", __func__); 173 174 return 0; 175 } 176 177 /** 178 * i2c_pnx_stop - stop a device 179 * @adap: pointer to I2C adapter structure 180 * 181 * Generate a STOP signal to terminate the master transaction. 182 */ 183 static void i2c_pnx_stop(struct i2c_pnx_algo_data *alg_data) 184 { 185 /* Only 1 msec max timeout due to interrupt context */ 186 long timeout = 1000; 187 188 dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", 189 __func__, ioread32(I2C_REG_STS(alg_data))); 190 191 /* Write a STOP bit to TX FIFO */ 192 iowrite32(0xff | stop_bit, I2C_REG_TX(alg_data)); 193 194 /* Wait until the STOP is seen. */ 195 while (timeout > 0 && 196 (ioread32(I2C_REG_STS(alg_data)) & mstatus_active)) { 197 /* may be called from interrupt context */ 198 udelay(1); 199 timeout--; 200 } 201 202 dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", 203 __func__, ioread32(I2C_REG_STS(alg_data))); 204 } 205 206 /** 207 * i2c_pnx_master_xmit - transmit data to slave 208 * @adap: pointer to I2C adapter structure 209 * 210 * Sends one byte of data to the slave 211 */ 212 static int i2c_pnx_master_xmit(struct i2c_pnx_algo_data *alg_data) 213 { 214 u32 val; 215 216 dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", 217 __func__, ioread32(I2C_REG_STS(alg_data))); 218 219 if (alg_data->mif.len > 0) { 220 /* We still have something to talk about... */ 221 val = *alg_data->mif.buf++; 222 223 if (alg_data->mif.len == 1) 224 val |= stop_bit; 225 226 alg_data->mif.len--; 227 iowrite32(val, I2C_REG_TX(alg_data)); 228 229 dev_dbg(&alg_data->adapter.dev, "%s(): xmit %#x [%d]\n", 230 __func__, val, alg_data->mif.len + 1); 231 232 if (alg_data->mif.len == 0) { 233 if (alg_data->last) { 234 /* Wait until the STOP is seen. */ 235 if (wait_timeout(alg_data)) 236 dev_err(&alg_data->adapter.dev, 237 "The bus is still active after timeout\n"); 238 } 239 /* Disable master interrupts */ 240 iowrite32(ioread32(I2C_REG_CTL(alg_data)) & 241 ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie), 242 I2C_REG_CTL(alg_data)); 243 244 del_timer_sync(&alg_data->mif.timer); 245 246 dev_dbg(&alg_data->adapter.dev, 247 "%s(): Waking up xfer routine.\n", 248 __func__); 249 250 complete(&alg_data->mif.complete); 251 } 252 } else if (alg_data->mif.len == 0) { 253 /* zero-sized transfer */ 254 i2c_pnx_stop(alg_data); 255 256 /* Disable master interrupts. */ 257 iowrite32(ioread32(I2C_REG_CTL(alg_data)) & 258 ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie), 259 I2C_REG_CTL(alg_data)); 260 261 /* Stop timer. */ 262 del_timer_sync(&alg_data->mif.timer); 263 dev_dbg(&alg_data->adapter.dev, 264 "%s(): Waking up xfer routine after zero-xfer.\n", 265 __func__); 266 267 complete(&alg_data->mif.complete); 268 } 269 270 dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", 271 __func__, ioread32(I2C_REG_STS(alg_data))); 272 273 return 0; 274 } 275 276 /** 277 * i2c_pnx_master_rcv - receive data from slave 278 * @adap: pointer to I2C adapter structure 279 * 280 * Reads one byte data from the slave 281 */ 282 static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data) 283 { 284 unsigned int val = 0; 285 u32 ctl = 0; 286 287 dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", 288 __func__, ioread32(I2C_REG_STS(alg_data))); 289 290 /* Check, whether there is already data, 291 * or we didn't 'ask' for it yet. 292 */ 293 if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) { 294 /* 'Asking' is done asynchronously, e.g. dummy TX of several 295 * bytes is done before the first actual RX arrives in FIFO. 296 * Therefore, ordered bytes (via TX) are counted separately. 297 */ 298 if (alg_data->mif.order) { 299 dev_dbg(&alg_data->adapter.dev, 300 "%s(): Write dummy data to fill Rx-fifo...\n", 301 __func__); 302 303 if (alg_data->mif.order == 1) { 304 /* Last byte, do not acknowledge next rcv. */ 305 val |= stop_bit; 306 307 /* 308 * Enable interrupt RFDAIE (data in Rx fifo), 309 * and disable DRMIE (need data for Tx) 310 */ 311 ctl = ioread32(I2C_REG_CTL(alg_data)); 312 ctl |= mcntrl_rffie | mcntrl_daie; 313 ctl &= ~mcntrl_drmie; 314 iowrite32(ctl, I2C_REG_CTL(alg_data)); 315 } 316 317 /* 318 * Now we'll 'ask' for data: 319 * For each byte we want to receive, we must 320 * write a (dummy) byte to the Tx-FIFO. 321 */ 322 iowrite32(val, I2C_REG_TX(alg_data)); 323 alg_data->mif.order--; 324 } 325 return 0; 326 } 327 328 /* Handle data. */ 329 if (alg_data->mif.len > 0) { 330 val = ioread32(I2C_REG_RX(alg_data)); 331 *alg_data->mif.buf++ = (u8) (val & 0xff); 332 dev_dbg(&alg_data->adapter.dev, "%s(): rcv 0x%x [%d]\n", 333 __func__, val, alg_data->mif.len); 334 335 alg_data->mif.len--; 336 if (alg_data->mif.len == 0) { 337 if (alg_data->last) 338 /* Wait until the STOP is seen. */ 339 if (wait_timeout(alg_data)) 340 dev_err(&alg_data->adapter.dev, 341 "The bus is still active after timeout\n"); 342 343 /* Disable master interrupts */ 344 ctl = ioread32(I2C_REG_CTL(alg_data)); 345 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | 346 mcntrl_drmie | mcntrl_daie); 347 iowrite32(ctl, I2C_REG_CTL(alg_data)); 348 349 /* Kill timer. */ 350 del_timer_sync(&alg_data->mif.timer); 351 complete(&alg_data->mif.complete); 352 } 353 } 354 355 dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", 356 __func__, ioread32(I2C_REG_STS(alg_data))); 357 358 return 0; 359 } 360 361 static irqreturn_t i2c_pnx_interrupt(int irq, void *dev_id) 362 { 363 struct i2c_pnx_algo_data *alg_data = dev_id; 364 u32 stat, ctl; 365 366 dev_dbg(&alg_data->adapter.dev, 367 "%s(): mstat = %x mctrl = %x, mode = %d\n", 368 __func__, 369 ioread32(I2C_REG_STS(alg_data)), 370 ioread32(I2C_REG_CTL(alg_data)), 371 alg_data->mif.mode); 372 stat = ioread32(I2C_REG_STS(alg_data)); 373 374 /* let's see what kind of event this is */ 375 if (stat & mstatus_afi) { 376 /* We lost arbitration in the midst of a transfer */ 377 alg_data->mif.ret = -EIO; 378 379 /* Disable master interrupts. */ 380 ctl = ioread32(I2C_REG_CTL(alg_data)); 381 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | 382 mcntrl_drmie); 383 iowrite32(ctl, I2C_REG_CTL(alg_data)); 384 385 /* Stop timer, to prevent timeout. */ 386 del_timer_sync(&alg_data->mif.timer); 387 complete(&alg_data->mif.complete); 388 } else if (stat & mstatus_nai) { 389 /* Slave did not acknowledge, generate a STOP */ 390 dev_dbg(&alg_data->adapter.dev, 391 "%s(): Slave did not acknowledge, generating a STOP.\n", 392 __func__); 393 i2c_pnx_stop(alg_data); 394 395 /* Disable master interrupts. */ 396 ctl = ioread32(I2C_REG_CTL(alg_data)); 397 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | 398 mcntrl_drmie); 399 iowrite32(ctl, I2C_REG_CTL(alg_data)); 400 401 /* Our return value. */ 402 alg_data->mif.ret = -EIO; 403 404 /* Stop timer, to prevent timeout. */ 405 del_timer_sync(&alg_data->mif.timer); 406 complete(&alg_data->mif.complete); 407 } else { 408 /* 409 * Two options: 410 * - Master Tx needs data. 411 * - There is data in the Rx-fifo 412 * The latter is only the case if we have requested for data, 413 * via a dummy write. (See 'i2c_pnx_master_rcv'.) 414 * We therefore check, as a sanity check, whether that interrupt 415 * has been enabled. 416 */ 417 if ((stat & mstatus_drmi) || !(stat & mstatus_rfe)) { 418 if (alg_data->mif.mode == I2C_SMBUS_WRITE) { 419 i2c_pnx_master_xmit(alg_data); 420 } else if (alg_data->mif.mode == I2C_SMBUS_READ) { 421 i2c_pnx_master_rcv(alg_data); 422 } 423 } 424 } 425 426 /* Clear TDI and AFI bits */ 427 stat = ioread32(I2C_REG_STS(alg_data)); 428 iowrite32(stat | mstatus_tdi | mstatus_afi, I2C_REG_STS(alg_data)); 429 430 dev_dbg(&alg_data->adapter.dev, 431 "%s(): exiting, stat = %x ctrl = %x.\n", 432 __func__, ioread32(I2C_REG_STS(alg_data)), 433 ioread32(I2C_REG_CTL(alg_data))); 434 435 return IRQ_HANDLED; 436 } 437 438 static void i2c_pnx_timeout(unsigned long data) 439 { 440 struct i2c_pnx_algo_data *alg_data = (struct i2c_pnx_algo_data *)data; 441 u32 ctl; 442 443 dev_err(&alg_data->adapter.dev, 444 "Master timed out. stat = %04x, cntrl = %04x. Resetting master...\n", 445 ioread32(I2C_REG_STS(alg_data)), 446 ioread32(I2C_REG_CTL(alg_data))); 447 448 /* Reset master and disable interrupts */ 449 ctl = ioread32(I2C_REG_CTL(alg_data)); 450 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | mcntrl_drmie); 451 iowrite32(ctl, I2C_REG_CTL(alg_data)); 452 453 ctl |= mcntrl_reset; 454 iowrite32(ctl, I2C_REG_CTL(alg_data)); 455 wait_reset(alg_data); 456 alg_data->mif.ret = -EIO; 457 complete(&alg_data->mif.complete); 458 } 459 460 static inline void bus_reset_if_active(struct i2c_pnx_algo_data *alg_data) 461 { 462 u32 stat; 463 464 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_active) { 465 dev_err(&alg_data->adapter.dev, 466 "%s: Bus is still active after xfer. Reset it...\n", 467 alg_data->adapter.name); 468 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, 469 I2C_REG_CTL(alg_data)); 470 wait_reset(alg_data); 471 } else if (!(stat & mstatus_rfe) || !(stat & mstatus_tfe)) { 472 /* If there is data in the fifo's after transfer, 473 * flush fifo's by reset. 474 */ 475 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, 476 I2C_REG_CTL(alg_data)); 477 wait_reset(alg_data); 478 } else if (stat & mstatus_nai) { 479 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, 480 I2C_REG_CTL(alg_data)); 481 wait_reset(alg_data); 482 } 483 } 484 485 /** 486 * i2c_pnx_xfer - generic transfer entry point 487 * @adap: pointer to I2C adapter structure 488 * @msgs: array of messages 489 * @num: number of messages 490 * 491 * Initiates the transfer 492 */ 493 static int 494 i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 495 { 496 struct i2c_msg *pmsg; 497 int rc = 0, completed = 0, i; 498 struct i2c_pnx_algo_data *alg_data = adap->algo_data; 499 u32 stat; 500 501 dev_dbg(&alg_data->adapter.dev, 502 "%s(): entering: %d messages, stat = %04x.\n", 503 __func__, num, ioread32(I2C_REG_STS(alg_data))); 504 505 bus_reset_if_active(alg_data); 506 507 /* Process transactions in a loop. */ 508 for (i = 0; rc >= 0 && i < num; i++) { 509 u8 addr; 510 511 pmsg = &msgs[i]; 512 addr = pmsg->addr; 513 514 if (pmsg->flags & I2C_M_TEN) { 515 dev_err(&alg_data->adapter.dev, 516 "%s: 10 bits addr not supported!\n", 517 alg_data->adapter.name); 518 rc = -EINVAL; 519 break; 520 } 521 522 alg_data->mif.buf = pmsg->buf; 523 alg_data->mif.len = pmsg->len; 524 alg_data->mif.order = pmsg->len; 525 alg_data->mif.mode = (pmsg->flags & I2C_M_RD) ? 526 I2C_SMBUS_READ : I2C_SMBUS_WRITE; 527 alg_data->mif.ret = 0; 528 alg_data->last = (i == num - 1); 529 530 dev_dbg(&alg_data->adapter.dev, "%s(): mode %d, %d bytes\n", 531 __func__, alg_data->mif.mode, alg_data->mif.len); 532 533 i2c_pnx_arm_timer(alg_data); 534 535 /* initialize the completion var */ 536 init_completion(&alg_data->mif.complete); 537 538 /* Enable master interrupt */ 539 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_afie | 540 mcntrl_naie | mcntrl_drmie, 541 I2C_REG_CTL(alg_data)); 542 543 /* Put start-code and slave-address on the bus. */ 544 rc = i2c_pnx_start(addr, alg_data); 545 if (rc < 0) 546 break; 547 548 /* Wait for completion */ 549 wait_for_completion(&alg_data->mif.complete); 550 551 if (!(rc = alg_data->mif.ret)) 552 completed++; 553 dev_dbg(&alg_data->adapter.dev, 554 "%s(): Complete, return code = %d.\n", 555 __func__, rc); 556 557 /* Clear TDI and AFI bits in case they are set. */ 558 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_tdi) { 559 dev_dbg(&alg_data->adapter.dev, 560 "%s: TDI still set... clearing now.\n", 561 alg_data->adapter.name); 562 iowrite32(stat, I2C_REG_STS(alg_data)); 563 } 564 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_afi) { 565 dev_dbg(&alg_data->adapter.dev, 566 "%s: AFI still set... clearing now.\n", 567 alg_data->adapter.name); 568 iowrite32(stat, I2C_REG_STS(alg_data)); 569 } 570 } 571 572 bus_reset_if_active(alg_data); 573 574 /* Cleanup to be sure... */ 575 alg_data->mif.buf = NULL; 576 alg_data->mif.len = 0; 577 alg_data->mif.order = 0; 578 579 dev_dbg(&alg_data->adapter.dev, "%s(): exiting, stat = %x\n", 580 __func__, ioread32(I2C_REG_STS(alg_data))); 581 582 if (completed != num) 583 return ((rc < 0) ? rc : -EREMOTEIO); 584 585 return num; 586 } 587 588 static u32 i2c_pnx_func(struct i2c_adapter *adapter) 589 { 590 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; 591 } 592 593 static struct i2c_algorithm pnx_algorithm = { 594 .master_xfer = i2c_pnx_xfer, 595 .functionality = i2c_pnx_func, 596 }; 597 598 #ifdef CONFIG_PM_SLEEP 599 static int i2c_pnx_controller_suspend(struct device *dev) 600 { 601 struct i2c_pnx_algo_data *alg_data = dev_get_drvdata(dev); 602 603 clk_disable_unprepare(alg_data->clk); 604 605 return 0; 606 } 607 608 static int i2c_pnx_controller_resume(struct device *dev) 609 { 610 struct i2c_pnx_algo_data *alg_data = dev_get_drvdata(dev); 611 612 return clk_prepare_enable(alg_data->clk); 613 } 614 615 static SIMPLE_DEV_PM_OPS(i2c_pnx_pm, 616 i2c_pnx_controller_suspend, i2c_pnx_controller_resume); 617 #define PNX_I2C_PM (&i2c_pnx_pm) 618 #else 619 #define PNX_I2C_PM NULL 620 #endif 621 622 static int i2c_pnx_probe(struct platform_device *pdev) 623 { 624 unsigned long tmp; 625 int ret = 0; 626 struct i2c_pnx_algo_data *alg_data; 627 unsigned long freq; 628 struct resource *res; 629 u32 speed = I2C_PNX_SPEED_KHZ_DEFAULT * 1000; 630 631 alg_data = devm_kzalloc(&pdev->dev, sizeof(*alg_data), GFP_KERNEL); 632 if (!alg_data) 633 return -ENOMEM; 634 635 platform_set_drvdata(pdev, alg_data); 636 637 alg_data->adapter.dev.parent = &pdev->dev; 638 alg_data->adapter.algo = &pnx_algorithm; 639 alg_data->adapter.algo_data = alg_data; 640 alg_data->adapter.nr = pdev->id; 641 642 alg_data->timeout = I2C_PNX_TIMEOUT_DEFAULT; 643 #ifdef CONFIG_OF 644 alg_data->adapter.dev.of_node = of_node_get(pdev->dev.of_node); 645 if (pdev->dev.of_node) { 646 of_property_read_u32(pdev->dev.of_node, "clock-frequency", 647 &speed); 648 /* 649 * At this point, it is planned to add an OF timeout property. 650 * As soon as there is a consensus about how to call and handle 651 * this, sth. like the following can be put here: 652 * 653 * of_property_read_u32(pdev->dev.of_node, "timeout", 654 * &alg_data->timeout); 655 */ 656 } 657 #endif 658 alg_data->clk = devm_clk_get(&pdev->dev, NULL); 659 if (IS_ERR(alg_data->clk)) 660 return PTR_ERR(alg_data->clk); 661 662 setup_timer(&alg_data->mif.timer, i2c_pnx_timeout, 663 (unsigned long)alg_data); 664 665 snprintf(alg_data->adapter.name, sizeof(alg_data->adapter.name), 666 "%s", pdev->name); 667 668 /* Register I/O resource */ 669 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 670 alg_data->ioaddr = devm_ioremap_resource(&pdev->dev, res); 671 if (IS_ERR(alg_data->ioaddr)) 672 return PTR_ERR(alg_data->ioaddr); 673 674 ret = clk_prepare_enable(alg_data->clk); 675 if (ret) 676 return ret; 677 678 freq = clk_get_rate(alg_data->clk); 679 680 /* 681 * Clock Divisor High This value is the number of system clocks 682 * the serial clock (SCL) will be high. 683 * For example, if the system clock period is 50 ns and the maximum 684 * desired serial period is 10000 ns (100 kHz), then CLKHI would be 685 * set to 0.5*(f_sys/f_i2c)-2=0.5*(20e6/100e3)-2=98. The actual value 686 * programmed into CLKHI will vary from this slightly due to 687 * variations in the output pad's rise and fall times as well as 688 * the deglitching filter length. 689 */ 690 691 tmp = (freq / speed) / 2 - 2; 692 if (tmp > 0x3FF) 693 tmp = 0x3FF; 694 iowrite32(tmp, I2C_REG_CKH(alg_data)); 695 iowrite32(tmp, I2C_REG_CKL(alg_data)); 696 697 iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data)); 698 if (wait_reset(alg_data)) { 699 ret = -ENODEV; 700 goto out_clock; 701 } 702 init_completion(&alg_data->mif.complete); 703 704 alg_data->irq = platform_get_irq(pdev, 0); 705 if (alg_data->irq < 0) { 706 dev_err(&pdev->dev, "Failed to get IRQ from platform resource\n"); 707 ret = alg_data->irq; 708 goto out_clock; 709 } 710 ret = devm_request_irq(&pdev->dev, alg_data->irq, i2c_pnx_interrupt, 711 0, pdev->name, alg_data); 712 if (ret) 713 goto out_clock; 714 715 /* Register this adapter with the I2C subsystem */ 716 ret = i2c_add_numbered_adapter(&alg_data->adapter); 717 if (ret < 0) 718 goto out_clock; 719 720 dev_dbg(&pdev->dev, "%s: Master at %#8x, irq %d.\n", 721 alg_data->adapter.name, res->start, alg_data->irq); 722 723 return 0; 724 725 out_clock: 726 clk_disable_unprepare(alg_data->clk); 727 return ret; 728 } 729 730 static int i2c_pnx_remove(struct platform_device *pdev) 731 { 732 struct i2c_pnx_algo_data *alg_data = platform_get_drvdata(pdev); 733 734 i2c_del_adapter(&alg_data->adapter); 735 clk_disable_unprepare(alg_data->clk); 736 737 return 0; 738 } 739 740 #ifdef CONFIG_OF 741 static const struct of_device_id i2c_pnx_of_match[] = { 742 { .compatible = "nxp,pnx-i2c" }, 743 { }, 744 }; 745 MODULE_DEVICE_TABLE(of, i2c_pnx_of_match); 746 #endif 747 748 static struct platform_driver i2c_pnx_driver = { 749 .driver = { 750 .name = "pnx-i2c", 751 .of_match_table = of_match_ptr(i2c_pnx_of_match), 752 .pm = PNX_I2C_PM, 753 }, 754 .probe = i2c_pnx_probe, 755 .remove = i2c_pnx_remove, 756 }; 757 758 static int __init i2c_adap_pnx_init(void) 759 { 760 return platform_driver_register(&i2c_pnx_driver); 761 } 762 763 static void __exit i2c_adap_pnx_exit(void) 764 { 765 platform_driver_unregister(&i2c_pnx_driver); 766 } 767 768 MODULE_AUTHOR("Vitaly Wool, Dennis Kovalev <source@mvista.com>"); 769 MODULE_DESCRIPTION("I2C driver for Philips IP3204-based I2C busses"); 770 MODULE_LICENSE("GPL"); 771 MODULE_ALIAS("platform:pnx-i2c"); 772 773 /* We need to make sure I2C is initialized before USB */ 774 subsys_initcall(i2c_adap_pnx_init); 775 module_exit(i2c_adap_pnx_exit); 776