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/completion.h> 19 #include <linux/platform_device.h> 20 #include <linux/io.h> 21 #include <linux/err.h> 22 #include <linux/clk.h> 23 #include <linux/slab.h> 24 #include <linux/of.h> 25 26 #define I2C_PNX_TIMEOUT_DEFAULT 10 /* msec */ 27 #define I2C_PNX_SPEED_KHZ_DEFAULT 100 28 #define I2C_PNX_REGION_SIZE 0x100 29 30 struct i2c_pnx_mif { 31 int ret; /* Return value */ 32 int mode; /* Interface mode */ 33 struct completion complete; /* I/O completion */ 34 u8 * buf; /* Data buffer */ 35 int len; /* Length of data buffer */ 36 int order; /* RX Bytes to order via TX */ 37 }; 38 39 struct i2c_pnx_algo_data { 40 void __iomem *ioaddr; 41 struct i2c_pnx_mif mif; 42 int last; 43 struct clk *clk; 44 struct i2c_adapter adapter; 45 int irq; 46 u32 timeout; 47 }; 48 49 enum { 50 mstatus_tdi = 0x00000001, 51 mstatus_afi = 0x00000002, 52 mstatus_nai = 0x00000004, 53 mstatus_drmi = 0x00000008, 54 mstatus_active = 0x00000020, 55 mstatus_scl = 0x00000040, 56 mstatus_sda = 0x00000080, 57 mstatus_rff = 0x00000100, 58 mstatus_rfe = 0x00000200, 59 mstatus_tff = 0x00000400, 60 mstatus_tfe = 0x00000800, 61 }; 62 63 enum { 64 mcntrl_tdie = 0x00000001, 65 mcntrl_afie = 0x00000002, 66 mcntrl_naie = 0x00000004, 67 mcntrl_drmie = 0x00000008, 68 mcntrl_drsie = 0x00000010, 69 mcntrl_rffie = 0x00000020, 70 mcntrl_daie = 0x00000040, 71 mcntrl_tffie = 0x00000080, 72 mcntrl_reset = 0x00000100, 73 mcntrl_cdbmode = 0x00000400, 74 }; 75 76 enum { 77 rw_bit = 1 << 0, 78 start_bit = 1 << 8, 79 stop_bit = 1 << 9, 80 }; 81 82 #define I2C_REG_RX(a) ((a)->ioaddr) /* Rx FIFO reg (RO) */ 83 #define I2C_REG_TX(a) ((a)->ioaddr) /* Tx FIFO reg (WO) */ 84 #define I2C_REG_STS(a) ((a)->ioaddr + 0x04) /* Status reg (RO) */ 85 #define I2C_REG_CTL(a) ((a)->ioaddr + 0x08) /* Ctl reg */ 86 #define I2C_REG_CKL(a) ((a)->ioaddr + 0x0c) /* Clock divider low */ 87 #define I2C_REG_CKH(a) ((a)->ioaddr + 0x10) /* Clock divider high */ 88 #define I2C_REG_ADR(a) ((a)->ioaddr + 0x14) /* I2C address */ 89 #define I2C_REG_RFL(a) ((a)->ioaddr + 0x18) /* Rx FIFO level (RO) */ 90 #define I2C_REG_TFL(a) ((a)->ioaddr + 0x1c) /* Tx FIFO level (RO) */ 91 #define I2C_REG_RXB(a) ((a)->ioaddr + 0x20) /* Num of bytes Rx-ed (RO) */ 92 #define I2C_REG_TXB(a) ((a)->ioaddr + 0x24) /* Num of bytes Tx-ed (RO) */ 93 #define I2C_REG_TXS(a) ((a)->ioaddr + 0x28) /* Tx slave FIFO (RO) */ 94 #define I2C_REG_STFL(a) ((a)->ioaddr + 0x2c) /* Tx slave FIFO level (RO) */ 95 96 static inline int wait_timeout(struct i2c_pnx_algo_data *data) 97 { 98 long timeout = data->timeout; 99 while (timeout > 0 && 100 (ioread32(I2C_REG_STS(data)) & mstatus_active)) { 101 mdelay(1); 102 timeout--; 103 } 104 return (timeout <= 0); 105 } 106 107 static inline int wait_reset(struct i2c_pnx_algo_data *data) 108 { 109 long timeout = data->timeout; 110 while (timeout > 0 && 111 (ioread32(I2C_REG_CTL(data)) & mcntrl_reset)) { 112 mdelay(1); 113 timeout--; 114 } 115 return (timeout <= 0); 116 } 117 118 /** 119 * i2c_pnx_start - start a device 120 * @slave_addr: slave address 121 * @alg_data: pointer to local driver data structure 122 * 123 * Generate a START signal in the desired mode. 124 */ 125 static int i2c_pnx_start(unsigned char slave_addr, 126 struct i2c_pnx_algo_data *alg_data) 127 { 128 dev_dbg(&alg_data->adapter.dev, "%s(): addr 0x%x mode %d\n", __func__, 129 slave_addr, alg_data->mif.mode); 130 131 /* Check for 7 bit slave addresses only */ 132 if (slave_addr & ~0x7f) { 133 dev_err(&alg_data->adapter.dev, 134 "%s: Invalid slave address %x. Only 7-bit addresses are supported\n", 135 alg_data->adapter.name, slave_addr); 136 return -EINVAL; 137 } 138 139 /* First, make sure bus is idle */ 140 if (wait_timeout(alg_data)) { 141 /* Somebody else is monopolizing the bus */ 142 dev_err(&alg_data->adapter.dev, 143 "%s: Bus busy. Slave addr = %02x, cntrl = %x, stat = %x\n", 144 alg_data->adapter.name, slave_addr, 145 ioread32(I2C_REG_CTL(alg_data)), 146 ioread32(I2C_REG_STS(alg_data))); 147 return -EBUSY; 148 } else if (ioread32(I2C_REG_STS(alg_data)) & mstatus_afi) { 149 /* Sorry, we lost the bus */ 150 dev_err(&alg_data->adapter.dev, 151 "%s: Arbitration failure. Slave addr = %02x\n", 152 alg_data->adapter.name, slave_addr); 153 return -EIO; 154 } 155 156 /* 157 * OK, I2C is enabled and we have the bus. 158 * Clear the current TDI and AFI status flags. 159 */ 160 iowrite32(ioread32(I2C_REG_STS(alg_data)) | mstatus_tdi | mstatus_afi, 161 I2C_REG_STS(alg_data)); 162 163 dev_dbg(&alg_data->adapter.dev, "%s(): sending %#x\n", __func__, 164 (slave_addr << 1) | start_bit | alg_data->mif.mode); 165 166 /* Write the slave address, START bit and R/W bit */ 167 iowrite32((slave_addr << 1) | start_bit | alg_data->mif.mode, 168 I2C_REG_TX(alg_data)); 169 170 dev_dbg(&alg_data->adapter.dev, "%s(): exit\n", __func__); 171 172 return 0; 173 } 174 175 /** 176 * i2c_pnx_stop - stop a device 177 * @alg_data: pointer to local driver data structure 178 * 179 * Generate a STOP signal to terminate the master transaction. 180 */ 181 static void i2c_pnx_stop(struct i2c_pnx_algo_data *alg_data) 182 { 183 /* Only 1 msec max timeout due to interrupt context */ 184 long timeout = 1000; 185 186 dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", 187 __func__, ioread32(I2C_REG_STS(alg_data))); 188 189 /* Write a STOP bit to TX FIFO */ 190 iowrite32(0xff | stop_bit, I2C_REG_TX(alg_data)); 191 192 /* Wait until the STOP is seen. */ 193 while (timeout > 0 && 194 (ioread32(I2C_REG_STS(alg_data)) & mstatus_active)) { 195 /* may be called from interrupt context */ 196 udelay(1); 197 timeout--; 198 } 199 200 dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", 201 __func__, ioread32(I2C_REG_STS(alg_data))); 202 } 203 204 /** 205 * i2c_pnx_master_xmit - transmit data to slave 206 * @alg_data: pointer to local driver data structure 207 * 208 * Sends one byte of data to the slave 209 */ 210 static int i2c_pnx_master_xmit(struct i2c_pnx_algo_data *alg_data) 211 { 212 u32 val; 213 214 dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", 215 __func__, ioread32(I2C_REG_STS(alg_data))); 216 217 if (alg_data->mif.len > 0) { 218 /* We still have something to talk about... */ 219 val = *alg_data->mif.buf++; 220 221 if (alg_data->mif.len == 1) 222 val |= stop_bit; 223 224 alg_data->mif.len--; 225 iowrite32(val, I2C_REG_TX(alg_data)); 226 227 dev_dbg(&alg_data->adapter.dev, "%s(): xmit %#x [%d]\n", 228 __func__, val, alg_data->mif.len + 1); 229 230 if (alg_data->mif.len == 0) { 231 if (alg_data->last) { 232 /* Wait until the STOP is seen. */ 233 if (wait_timeout(alg_data)) 234 dev_err(&alg_data->adapter.dev, 235 "The bus is still active after timeout\n"); 236 } 237 /* Disable master interrupts */ 238 iowrite32(ioread32(I2C_REG_CTL(alg_data)) & 239 ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie), 240 I2C_REG_CTL(alg_data)); 241 242 dev_dbg(&alg_data->adapter.dev, 243 "%s(): Waking up xfer routine.\n", 244 __func__); 245 246 complete(&alg_data->mif.complete); 247 } 248 } else if (alg_data->mif.len == 0) { 249 /* zero-sized transfer */ 250 i2c_pnx_stop(alg_data); 251 252 /* Disable master interrupts. */ 253 iowrite32(ioread32(I2C_REG_CTL(alg_data)) & 254 ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie), 255 I2C_REG_CTL(alg_data)); 256 257 dev_dbg(&alg_data->adapter.dev, 258 "%s(): Waking up xfer routine after zero-xfer.\n", 259 __func__); 260 261 complete(&alg_data->mif.complete); 262 } 263 264 dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", 265 __func__, ioread32(I2C_REG_STS(alg_data))); 266 267 return 0; 268 } 269 270 /** 271 * i2c_pnx_master_rcv - receive data from slave 272 * @alg_data: pointer to local driver data structure 273 * 274 * Reads one byte data from the slave 275 */ 276 static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data) 277 { 278 unsigned int val = 0; 279 u32 ctl = 0; 280 281 dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", 282 __func__, ioread32(I2C_REG_STS(alg_data))); 283 284 /* Check, whether there is already data, 285 * or we didn't 'ask' for it yet. 286 */ 287 if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) { 288 /* 'Asking' is done asynchronously, e.g. dummy TX of several 289 * bytes is done before the first actual RX arrives in FIFO. 290 * Therefore, ordered bytes (via TX) are counted separately. 291 */ 292 if (alg_data->mif.order) { 293 dev_dbg(&alg_data->adapter.dev, 294 "%s(): Write dummy data to fill Rx-fifo...\n", 295 __func__); 296 297 if (alg_data->mif.order == 1) { 298 /* Last byte, do not acknowledge next rcv. */ 299 val |= stop_bit; 300 301 /* 302 * Enable interrupt RFDAIE (data in Rx fifo), 303 * and disable DRMIE (need data for Tx) 304 */ 305 ctl = ioread32(I2C_REG_CTL(alg_data)); 306 ctl |= mcntrl_rffie | mcntrl_daie; 307 ctl &= ~mcntrl_drmie; 308 iowrite32(ctl, I2C_REG_CTL(alg_data)); 309 } 310 311 /* 312 * Now we'll 'ask' for data: 313 * For each byte we want to receive, we must 314 * write a (dummy) byte to the Tx-FIFO. 315 */ 316 iowrite32(val, I2C_REG_TX(alg_data)); 317 alg_data->mif.order--; 318 } 319 return 0; 320 } 321 322 /* Handle data. */ 323 if (alg_data->mif.len > 0) { 324 val = ioread32(I2C_REG_RX(alg_data)); 325 *alg_data->mif.buf++ = (u8) (val & 0xff); 326 dev_dbg(&alg_data->adapter.dev, "%s(): rcv 0x%x [%d]\n", 327 __func__, val, alg_data->mif.len); 328 329 alg_data->mif.len--; 330 if (alg_data->mif.len == 0) { 331 if (alg_data->last) 332 /* Wait until the STOP is seen. */ 333 if (wait_timeout(alg_data)) 334 dev_err(&alg_data->adapter.dev, 335 "The bus is still active after timeout\n"); 336 337 /* Disable master interrupts */ 338 ctl = ioread32(I2C_REG_CTL(alg_data)); 339 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | 340 mcntrl_drmie | mcntrl_daie); 341 iowrite32(ctl, I2C_REG_CTL(alg_data)); 342 343 complete(&alg_data->mif.complete); 344 } 345 } 346 347 dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", 348 __func__, ioread32(I2C_REG_STS(alg_data))); 349 350 return 0; 351 } 352 353 static irqreturn_t i2c_pnx_interrupt(int irq, void *dev_id) 354 { 355 struct i2c_pnx_algo_data *alg_data = dev_id; 356 u32 stat, ctl; 357 358 dev_dbg(&alg_data->adapter.dev, 359 "%s(): mstat = %x mctrl = %x, mode = %d\n", 360 __func__, 361 ioread32(I2C_REG_STS(alg_data)), 362 ioread32(I2C_REG_CTL(alg_data)), 363 alg_data->mif.mode); 364 stat = ioread32(I2C_REG_STS(alg_data)); 365 366 /* let's see what kind of event this is */ 367 if (stat & mstatus_afi) { 368 /* We lost arbitration in the midst of a transfer */ 369 alg_data->mif.ret = -EIO; 370 371 /* Disable master interrupts. */ 372 ctl = ioread32(I2C_REG_CTL(alg_data)); 373 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | 374 mcntrl_drmie); 375 iowrite32(ctl, I2C_REG_CTL(alg_data)); 376 377 complete(&alg_data->mif.complete); 378 } else if (stat & mstatus_nai) { 379 /* Slave did not acknowledge, generate a STOP */ 380 dev_dbg(&alg_data->adapter.dev, 381 "%s(): Slave did not acknowledge, generating a STOP.\n", 382 __func__); 383 i2c_pnx_stop(alg_data); 384 385 /* Disable master interrupts. */ 386 ctl = ioread32(I2C_REG_CTL(alg_data)); 387 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | 388 mcntrl_drmie); 389 iowrite32(ctl, I2C_REG_CTL(alg_data)); 390 391 /* Our return value. */ 392 alg_data->mif.ret = -EIO; 393 394 complete(&alg_data->mif.complete); 395 } else { 396 /* 397 * Two options: 398 * - Master Tx needs data. 399 * - There is data in the Rx-fifo 400 * The latter is only the case if we have requested for data, 401 * via a dummy write. (See 'i2c_pnx_master_rcv'.) 402 * We therefore check, as a sanity check, whether that interrupt 403 * has been enabled. 404 */ 405 if ((stat & mstatus_drmi) || !(stat & mstatus_rfe)) { 406 if (alg_data->mif.mode == I2C_SMBUS_WRITE) { 407 i2c_pnx_master_xmit(alg_data); 408 } else if (alg_data->mif.mode == I2C_SMBUS_READ) { 409 i2c_pnx_master_rcv(alg_data); 410 } 411 } 412 } 413 414 /* Clear TDI and AFI bits */ 415 stat = ioread32(I2C_REG_STS(alg_data)); 416 iowrite32(stat | mstatus_tdi | mstatus_afi, I2C_REG_STS(alg_data)); 417 418 dev_dbg(&alg_data->adapter.dev, 419 "%s(): exiting, stat = %x ctrl = %x.\n", 420 __func__, ioread32(I2C_REG_STS(alg_data)), 421 ioread32(I2C_REG_CTL(alg_data))); 422 423 return IRQ_HANDLED; 424 } 425 426 static void i2c_pnx_timeout(struct i2c_pnx_algo_data *alg_data) 427 { 428 u32 ctl; 429 430 dev_err(&alg_data->adapter.dev, 431 "Master timed out. stat = %04x, cntrl = %04x. Resetting master...\n", 432 ioread32(I2C_REG_STS(alg_data)), 433 ioread32(I2C_REG_CTL(alg_data))); 434 435 /* Reset master and disable interrupts */ 436 ctl = ioread32(I2C_REG_CTL(alg_data)); 437 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | mcntrl_drmie); 438 iowrite32(ctl, I2C_REG_CTL(alg_data)); 439 440 ctl |= mcntrl_reset; 441 iowrite32(ctl, I2C_REG_CTL(alg_data)); 442 wait_reset(alg_data); 443 alg_data->mif.ret = -EIO; 444 } 445 446 static inline void bus_reset_if_active(struct i2c_pnx_algo_data *alg_data) 447 { 448 u32 stat; 449 450 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_active) { 451 dev_err(&alg_data->adapter.dev, 452 "%s: Bus is still active after xfer. Reset it...\n", 453 alg_data->adapter.name); 454 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, 455 I2C_REG_CTL(alg_data)); 456 wait_reset(alg_data); 457 } else if (!(stat & mstatus_rfe) || !(stat & mstatus_tfe)) { 458 /* If there is data in the fifo's after transfer, 459 * flush fifo's by reset. 460 */ 461 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, 462 I2C_REG_CTL(alg_data)); 463 wait_reset(alg_data); 464 } else if (stat & mstatus_nai) { 465 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, 466 I2C_REG_CTL(alg_data)); 467 wait_reset(alg_data); 468 } 469 } 470 471 /** 472 * i2c_pnx_xfer - generic transfer entry point 473 * @adap: pointer to I2C adapter structure 474 * @msgs: array of messages 475 * @num: number of messages 476 * 477 * Initiates the transfer 478 */ 479 static int 480 i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 481 { 482 struct i2c_msg *pmsg; 483 int rc = 0, completed = 0, i; 484 struct i2c_pnx_algo_data *alg_data = adap->algo_data; 485 unsigned long time_left; 486 u32 stat; 487 488 dev_dbg(&alg_data->adapter.dev, 489 "%s(): entering: %d messages, stat = %04x.\n", 490 __func__, num, ioread32(I2C_REG_STS(alg_data))); 491 492 bus_reset_if_active(alg_data); 493 494 /* Process transactions in a loop. */ 495 for (i = 0; rc >= 0 && i < num; i++) { 496 u8 addr; 497 498 pmsg = &msgs[i]; 499 addr = pmsg->addr; 500 501 if (pmsg->flags & I2C_M_TEN) { 502 dev_err(&alg_data->adapter.dev, 503 "%s: 10 bits addr not supported!\n", 504 alg_data->adapter.name); 505 rc = -EINVAL; 506 break; 507 } 508 509 alg_data->mif.buf = pmsg->buf; 510 alg_data->mif.len = pmsg->len; 511 alg_data->mif.order = pmsg->len; 512 alg_data->mif.mode = (pmsg->flags & I2C_M_RD) ? 513 I2C_SMBUS_READ : I2C_SMBUS_WRITE; 514 alg_data->mif.ret = 0; 515 alg_data->last = (i == num - 1); 516 517 dev_dbg(&alg_data->adapter.dev, "%s(): mode %d, %d bytes\n", 518 __func__, alg_data->mif.mode, alg_data->mif.len); 519 520 521 /* initialize the completion var */ 522 init_completion(&alg_data->mif.complete); 523 524 /* Enable master interrupt */ 525 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_afie | 526 mcntrl_naie | mcntrl_drmie, 527 I2C_REG_CTL(alg_data)); 528 529 /* Put start-code and slave-address on the bus. */ 530 rc = i2c_pnx_start(addr, alg_data); 531 if (rc < 0) 532 break; 533 534 /* Wait for completion */ 535 time_left = wait_for_completion_timeout(&alg_data->mif.complete, 536 alg_data->timeout); 537 if (time_left == 0) 538 i2c_pnx_timeout(alg_data); 539 540 if (!(rc = alg_data->mif.ret)) 541 completed++; 542 dev_dbg(&alg_data->adapter.dev, 543 "%s(): Complete, return code = %d.\n", 544 __func__, rc); 545 546 /* Clear TDI and AFI bits in case they are set. */ 547 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_tdi) { 548 dev_dbg(&alg_data->adapter.dev, 549 "%s: TDI still set... clearing now.\n", 550 alg_data->adapter.name); 551 iowrite32(stat, I2C_REG_STS(alg_data)); 552 } 553 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_afi) { 554 dev_dbg(&alg_data->adapter.dev, 555 "%s: AFI still set... clearing now.\n", 556 alg_data->adapter.name); 557 iowrite32(stat, I2C_REG_STS(alg_data)); 558 } 559 } 560 561 bus_reset_if_active(alg_data); 562 563 /* Cleanup to be sure... */ 564 alg_data->mif.buf = NULL; 565 alg_data->mif.len = 0; 566 alg_data->mif.order = 0; 567 568 dev_dbg(&alg_data->adapter.dev, "%s(): exiting, stat = %x\n", 569 __func__, ioread32(I2C_REG_STS(alg_data))); 570 571 if (completed != num) 572 return ((rc < 0) ? rc : -EREMOTEIO); 573 574 return num; 575 } 576 577 static u32 i2c_pnx_func(struct i2c_adapter *adapter) 578 { 579 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; 580 } 581 582 static const struct i2c_algorithm pnx_algorithm = { 583 .master_xfer = i2c_pnx_xfer, 584 .functionality = i2c_pnx_func, 585 }; 586 587 static int i2c_pnx_controller_suspend(struct device *dev) 588 { 589 struct i2c_pnx_algo_data *alg_data = dev_get_drvdata(dev); 590 591 clk_disable_unprepare(alg_data->clk); 592 593 return 0; 594 } 595 596 static int i2c_pnx_controller_resume(struct device *dev) 597 { 598 struct i2c_pnx_algo_data *alg_data = dev_get_drvdata(dev); 599 600 return clk_prepare_enable(alg_data->clk); 601 } 602 603 static DEFINE_SIMPLE_DEV_PM_OPS(i2c_pnx_pm, 604 i2c_pnx_controller_suspend, 605 i2c_pnx_controller_resume); 606 607 static int i2c_pnx_probe(struct platform_device *pdev) 608 { 609 unsigned long tmp; 610 int ret = 0; 611 struct i2c_pnx_algo_data *alg_data; 612 unsigned long freq; 613 struct resource *res; 614 u32 speed = I2C_PNX_SPEED_KHZ_DEFAULT * 1000; 615 616 alg_data = devm_kzalloc(&pdev->dev, sizeof(*alg_data), GFP_KERNEL); 617 if (!alg_data) 618 return -ENOMEM; 619 620 platform_set_drvdata(pdev, alg_data); 621 622 alg_data->adapter.dev.parent = &pdev->dev; 623 alg_data->adapter.algo = &pnx_algorithm; 624 alg_data->adapter.algo_data = alg_data; 625 alg_data->adapter.nr = pdev->id; 626 627 alg_data->timeout = msecs_to_jiffies(I2C_PNX_TIMEOUT_DEFAULT); 628 if (alg_data->timeout <= 1) 629 alg_data->timeout = 2; 630 631 #ifdef CONFIG_OF 632 alg_data->adapter.dev.of_node = of_node_get(pdev->dev.of_node); 633 if (pdev->dev.of_node) { 634 of_property_read_u32(pdev->dev.of_node, "clock-frequency", 635 &speed); 636 /* 637 * At this point, it is planned to add an OF timeout property. 638 * As soon as there is a consensus about how to call and handle 639 * this, sth. like the following can be put here: 640 * 641 * of_property_read_u32(pdev->dev.of_node, "timeout", 642 * &alg_data->timeout); 643 */ 644 } 645 #endif 646 alg_data->clk = devm_clk_get(&pdev->dev, NULL); 647 if (IS_ERR(alg_data->clk)) 648 return PTR_ERR(alg_data->clk); 649 650 snprintf(alg_data->adapter.name, sizeof(alg_data->adapter.name), 651 "%s", pdev->name); 652 653 /* Register I/O resource */ 654 alg_data->ioaddr = devm_platform_get_and_ioremap_resource(pdev, 0, &res); 655 if (IS_ERR(alg_data->ioaddr)) 656 return PTR_ERR(alg_data->ioaddr); 657 658 ret = clk_prepare_enable(alg_data->clk); 659 if (ret) 660 return ret; 661 662 freq = clk_get_rate(alg_data->clk); 663 664 /* 665 * Clock Divisor High This value is the number of system clocks 666 * the serial clock (SCL) will be high. 667 * For example, if the system clock period is 50 ns and the maximum 668 * desired serial period is 10000 ns (100 kHz), then CLKHI would be 669 * set to 0.5*(f_sys/f_i2c)-2=0.5*(20e6/100e3)-2=98. The actual value 670 * programmed into CLKHI will vary from this slightly due to 671 * variations in the output pad's rise and fall times as well as 672 * the deglitching filter length. 673 */ 674 675 tmp = (freq / speed) / 2 - 2; 676 if (tmp > 0x3FF) 677 tmp = 0x3FF; 678 iowrite32(tmp, I2C_REG_CKH(alg_data)); 679 iowrite32(tmp, I2C_REG_CKL(alg_data)); 680 681 iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data)); 682 if (wait_reset(alg_data)) { 683 ret = -ENODEV; 684 goto out_clock; 685 } 686 init_completion(&alg_data->mif.complete); 687 688 alg_data->irq = platform_get_irq(pdev, 0); 689 if (alg_data->irq < 0) { 690 ret = alg_data->irq; 691 goto out_clock; 692 } 693 ret = devm_request_irq(&pdev->dev, alg_data->irq, i2c_pnx_interrupt, 694 0, pdev->name, alg_data); 695 if (ret) 696 goto out_clock; 697 698 /* Register this adapter with the I2C subsystem */ 699 ret = i2c_add_numbered_adapter(&alg_data->adapter); 700 if (ret < 0) 701 goto out_clock; 702 703 dev_dbg(&pdev->dev, "%s: Master at %pap, irq %d.\n", 704 alg_data->adapter.name, &res->start, alg_data->irq); 705 706 return 0; 707 708 out_clock: 709 clk_disable_unprepare(alg_data->clk); 710 return ret; 711 } 712 713 static void i2c_pnx_remove(struct platform_device *pdev) 714 { 715 struct i2c_pnx_algo_data *alg_data = platform_get_drvdata(pdev); 716 717 i2c_del_adapter(&alg_data->adapter); 718 clk_disable_unprepare(alg_data->clk); 719 } 720 721 #ifdef CONFIG_OF 722 static const struct of_device_id i2c_pnx_of_match[] = { 723 { .compatible = "nxp,pnx-i2c" }, 724 { } 725 }; 726 MODULE_DEVICE_TABLE(of, i2c_pnx_of_match); 727 #endif 728 729 static struct platform_driver i2c_pnx_driver = { 730 .driver = { 731 .name = "pnx-i2c", 732 .of_match_table = of_match_ptr(i2c_pnx_of_match), 733 .pm = pm_sleep_ptr(&i2c_pnx_pm), 734 }, 735 .probe = i2c_pnx_probe, 736 .remove_new = i2c_pnx_remove, 737 }; 738 739 static int __init i2c_adap_pnx_init(void) 740 { 741 return platform_driver_register(&i2c_pnx_driver); 742 } 743 744 static void __exit i2c_adap_pnx_exit(void) 745 { 746 platform_driver_unregister(&i2c_pnx_driver); 747 } 748 749 MODULE_AUTHOR("Vitaly Wool"); 750 MODULE_AUTHOR("Dennis Kovalev <source@mvista.com>"); 751 MODULE_DESCRIPTION("I2C driver for Philips IP3204-based I2C busses"); 752 MODULE_LICENSE("GPL"); 753 MODULE_ALIAS("platform:pnx-i2c"); 754 755 /* We need to make sure I2C is initialized before USB */ 756 subsys_initcall(i2c_adap_pnx_init); 757 module_exit(i2c_adap_pnx_exit); 758