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/io.h> 22 #include <linux/err.h> 23 #include <linux/clk.h> 24 #include <linux/slab.h> 25 #include <linux/of.h> 26 27 #define I2C_PNX_TIMEOUT_DEFAULT 10 /* msec */ 28 #define I2C_PNX_SPEED_KHZ_DEFAULT 100 29 #define I2C_PNX_REGION_SIZE 0x100 30 31 struct i2c_pnx_mif { 32 int ret; /* Return value */ 33 int mode; /* Interface mode */ 34 struct completion complete; /* I/O completion */ 35 struct timer_list timer; /* Timeout */ 36 u8 * buf; /* Data buffer */ 37 int len; /* Length of data buffer */ 38 int order; /* RX Bytes to order via TX */ 39 }; 40 41 struct i2c_pnx_algo_data { 42 void __iomem *ioaddr; 43 struct i2c_pnx_mif mif; 44 int last; 45 struct clk *clk; 46 struct i2c_adapter adapter; 47 int irq; 48 u32 timeout; 49 }; 50 51 enum { 52 mstatus_tdi = 0x00000001, 53 mstatus_afi = 0x00000002, 54 mstatus_nai = 0x00000004, 55 mstatus_drmi = 0x00000008, 56 mstatus_active = 0x00000020, 57 mstatus_scl = 0x00000040, 58 mstatus_sda = 0x00000080, 59 mstatus_rff = 0x00000100, 60 mstatus_rfe = 0x00000200, 61 mstatus_tff = 0x00000400, 62 mstatus_tfe = 0x00000800, 63 }; 64 65 enum { 66 mcntrl_tdie = 0x00000001, 67 mcntrl_afie = 0x00000002, 68 mcntrl_naie = 0x00000004, 69 mcntrl_drmie = 0x00000008, 70 mcntrl_drsie = 0x00000010, 71 mcntrl_rffie = 0x00000020, 72 mcntrl_daie = 0x00000040, 73 mcntrl_tffie = 0x00000080, 74 mcntrl_reset = 0x00000100, 75 mcntrl_cdbmode = 0x00000400, 76 }; 77 78 enum { 79 rw_bit = 1 << 0, 80 start_bit = 1 << 8, 81 stop_bit = 1 << 9, 82 }; 83 84 #define I2C_REG_RX(a) ((a)->ioaddr) /* Rx FIFO reg (RO) */ 85 #define I2C_REG_TX(a) ((a)->ioaddr) /* Tx FIFO reg (WO) */ 86 #define I2C_REG_STS(a) ((a)->ioaddr + 0x04) /* Status reg (RO) */ 87 #define I2C_REG_CTL(a) ((a)->ioaddr + 0x08) /* Ctl reg */ 88 #define I2C_REG_CKL(a) ((a)->ioaddr + 0x0c) /* Clock divider low */ 89 #define I2C_REG_CKH(a) ((a)->ioaddr + 0x10) /* Clock divider high */ 90 #define I2C_REG_ADR(a) ((a)->ioaddr + 0x14) /* I2C address */ 91 #define I2C_REG_RFL(a) ((a)->ioaddr + 0x18) /* Rx FIFO level (RO) */ 92 #define I2C_REG_TFL(a) ((a)->ioaddr + 0x1c) /* Tx FIFO level (RO) */ 93 #define I2C_REG_RXB(a) ((a)->ioaddr + 0x20) /* Num of bytes Rx-ed (RO) */ 94 #define I2C_REG_TXB(a) ((a)->ioaddr + 0x24) /* Num of bytes Tx-ed (RO) */ 95 #define I2C_REG_TXS(a) ((a)->ioaddr + 0x28) /* Tx slave FIFO (RO) */ 96 #define I2C_REG_STFL(a) ((a)->ioaddr + 0x2c) /* Tx slave FIFO level (RO) */ 97 98 static inline int wait_timeout(struct i2c_pnx_algo_data *data) 99 { 100 long timeout = data->timeout; 101 while (timeout > 0 && 102 (ioread32(I2C_REG_STS(data)) & mstatus_active)) { 103 mdelay(1); 104 timeout--; 105 } 106 return (timeout <= 0); 107 } 108 109 static inline int wait_reset(struct i2c_pnx_algo_data *data) 110 { 111 long timeout = data->timeout; 112 while (timeout > 0 && 113 (ioread32(I2C_REG_CTL(data)) & mcntrl_reset)) { 114 mdelay(1); 115 timeout--; 116 } 117 return (timeout <= 0); 118 } 119 120 static inline void i2c_pnx_arm_timer(struct i2c_pnx_algo_data *alg_data) 121 { 122 struct timer_list *timer = &alg_data->mif.timer; 123 unsigned long expires = msecs_to_jiffies(alg_data->timeout); 124 125 if (expires <= 1) 126 expires = 2; 127 128 del_timer_sync(timer); 129 130 dev_dbg(&alg_data->adapter.dev, "Timer armed at %lu plus %lu jiffies.\n", 131 jiffies, expires); 132 133 timer->expires = jiffies + expires; 134 135 add_timer(timer); 136 } 137 138 /** 139 * i2c_pnx_start - start a device 140 * @slave_addr: slave address 141 * @alg_data: pointer to local driver data structure 142 * 143 * Generate a START signal in the desired mode. 144 */ 145 static int i2c_pnx_start(unsigned char slave_addr, 146 struct i2c_pnx_algo_data *alg_data) 147 { 148 dev_dbg(&alg_data->adapter.dev, "%s(): addr 0x%x mode %d\n", __func__, 149 slave_addr, alg_data->mif.mode); 150 151 /* Check for 7 bit slave addresses only */ 152 if (slave_addr & ~0x7f) { 153 dev_err(&alg_data->adapter.dev, 154 "%s: Invalid slave address %x. Only 7-bit addresses are supported\n", 155 alg_data->adapter.name, slave_addr); 156 return -EINVAL; 157 } 158 159 /* First, make sure bus is idle */ 160 if (wait_timeout(alg_data)) { 161 /* Somebody else is monopolizing the bus */ 162 dev_err(&alg_data->adapter.dev, 163 "%s: Bus busy. Slave addr = %02x, cntrl = %x, stat = %x\n", 164 alg_data->adapter.name, slave_addr, 165 ioread32(I2C_REG_CTL(alg_data)), 166 ioread32(I2C_REG_STS(alg_data))); 167 return -EBUSY; 168 } else if (ioread32(I2C_REG_STS(alg_data)) & mstatus_afi) { 169 /* Sorry, we lost the bus */ 170 dev_err(&alg_data->adapter.dev, 171 "%s: Arbitration failure. Slave addr = %02x\n", 172 alg_data->adapter.name, slave_addr); 173 return -EIO; 174 } 175 176 /* 177 * OK, I2C is enabled and we have the bus. 178 * Clear the current TDI and AFI status flags. 179 */ 180 iowrite32(ioread32(I2C_REG_STS(alg_data)) | mstatus_tdi | mstatus_afi, 181 I2C_REG_STS(alg_data)); 182 183 dev_dbg(&alg_data->adapter.dev, "%s(): sending %#x\n", __func__, 184 (slave_addr << 1) | start_bit | alg_data->mif.mode); 185 186 /* Write the slave address, START bit and R/W bit */ 187 iowrite32((slave_addr << 1) | start_bit | alg_data->mif.mode, 188 I2C_REG_TX(alg_data)); 189 190 dev_dbg(&alg_data->adapter.dev, "%s(): exit\n", __func__); 191 192 return 0; 193 } 194 195 /** 196 * i2c_pnx_stop - stop a device 197 * @alg_data: pointer to local driver data structure 198 * 199 * Generate a STOP signal to terminate the master transaction. 200 */ 201 static void i2c_pnx_stop(struct i2c_pnx_algo_data *alg_data) 202 { 203 /* Only 1 msec max timeout due to interrupt context */ 204 long timeout = 1000; 205 206 dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", 207 __func__, ioread32(I2C_REG_STS(alg_data))); 208 209 /* Write a STOP bit to TX FIFO */ 210 iowrite32(0xff | stop_bit, I2C_REG_TX(alg_data)); 211 212 /* Wait until the STOP is seen. */ 213 while (timeout > 0 && 214 (ioread32(I2C_REG_STS(alg_data)) & mstatus_active)) { 215 /* may be called from interrupt context */ 216 udelay(1); 217 timeout--; 218 } 219 220 dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", 221 __func__, ioread32(I2C_REG_STS(alg_data))); 222 } 223 224 /** 225 * i2c_pnx_master_xmit - transmit data to slave 226 * @alg_data: pointer to local driver data structure 227 * 228 * Sends one byte of data to the slave 229 */ 230 static int i2c_pnx_master_xmit(struct i2c_pnx_algo_data *alg_data) 231 { 232 u32 val; 233 234 dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", 235 __func__, ioread32(I2C_REG_STS(alg_data))); 236 237 if (alg_data->mif.len > 0) { 238 /* We still have something to talk about... */ 239 val = *alg_data->mif.buf++; 240 241 if (alg_data->mif.len == 1) 242 val |= stop_bit; 243 244 alg_data->mif.len--; 245 iowrite32(val, I2C_REG_TX(alg_data)); 246 247 dev_dbg(&alg_data->adapter.dev, "%s(): xmit %#x [%d]\n", 248 __func__, val, alg_data->mif.len + 1); 249 250 if (alg_data->mif.len == 0) { 251 if (alg_data->last) { 252 /* Wait until the STOP is seen. */ 253 if (wait_timeout(alg_data)) 254 dev_err(&alg_data->adapter.dev, 255 "The bus is still active after timeout\n"); 256 } 257 /* Disable master interrupts */ 258 iowrite32(ioread32(I2C_REG_CTL(alg_data)) & 259 ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie), 260 I2C_REG_CTL(alg_data)); 261 262 del_timer_sync(&alg_data->mif.timer); 263 264 dev_dbg(&alg_data->adapter.dev, 265 "%s(): Waking up xfer routine.\n", 266 __func__); 267 268 complete(&alg_data->mif.complete); 269 } 270 } else if (alg_data->mif.len == 0) { 271 /* zero-sized transfer */ 272 i2c_pnx_stop(alg_data); 273 274 /* Disable master interrupts. */ 275 iowrite32(ioread32(I2C_REG_CTL(alg_data)) & 276 ~(mcntrl_afie | mcntrl_naie | mcntrl_drmie), 277 I2C_REG_CTL(alg_data)); 278 279 /* Stop timer. */ 280 del_timer_sync(&alg_data->mif.timer); 281 dev_dbg(&alg_data->adapter.dev, 282 "%s(): Waking up xfer routine after zero-xfer.\n", 283 __func__); 284 285 complete(&alg_data->mif.complete); 286 } 287 288 dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", 289 __func__, ioread32(I2C_REG_STS(alg_data))); 290 291 return 0; 292 } 293 294 /** 295 * i2c_pnx_master_rcv - receive data from slave 296 * @alg_data: pointer to local driver data structure 297 * 298 * Reads one byte data from the slave 299 */ 300 static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data) 301 { 302 unsigned int val = 0; 303 u32 ctl = 0; 304 305 dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n", 306 __func__, ioread32(I2C_REG_STS(alg_data))); 307 308 /* Check, whether there is already data, 309 * or we didn't 'ask' for it yet. 310 */ 311 if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) { 312 /* 'Asking' is done asynchronously, e.g. dummy TX of several 313 * bytes is done before the first actual RX arrives in FIFO. 314 * Therefore, ordered bytes (via TX) are counted separately. 315 */ 316 if (alg_data->mif.order) { 317 dev_dbg(&alg_data->adapter.dev, 318 "%s(): Write dummy data to fill Rx-fifo...\n", 319 __func__); 320 321 if (alg_data->mif.order == 1) { 322 /* Last byte, do not acknowledge next rcv. */ 323 val |= stop_bit; 324 325 /* 326 * Enable interrupt RFDAIE (data in Rx fifo), 327 * and disable DRMIE (need data for Tx) 328 */ 329 ctl = ioread32(I2C_REG_CTL(alg_data)); 330 ctl |= mcntrl_rffie | mcntrl_daie; 331 ctl &= ~mcntrl_drmie; 332 iowrite32(ctl, I2C_REG_CTL(alg_data)); 333 } 334 335 /* 336 * Now we'll 'ask' for data: 337 * For each byte we want to receive, we must 338 * write a (dummy) byte to the Tx-FIFO. 339 */ 340 iowrite32(val, I2C_REG_TX(alg_data)); 341 alg_data->mif.order--; 342 } 343 return 0; 344 } 345 346 /* Handle data. */ 347 if (alg_data->mif.len > 0) { 348 val = ioread32(I2C_REG_RX(alg_data)); 349 *alg_data->mif.buf++ = (u8) (val & 0xff); 350 dev_dbg(&alg_data->adapter.dev, "%s(): rcv 0x%x [%d]\n", 351 __func__, val, alg_data->mif.len); 352 353 alg_data->mif.len--; 354 if (alg_data->mif.len == 0) { 355 if (alg_data->last) 356 /* Wait until the STOP is seen. */ 357 if (wait_timeout(alg_data)) 358 dev_err(&alg_data->adapter.dev, 359 "The bus is still active after timeout\n"); 360 361 /* Disable master interrupts */ 362 ctl = ioread32(I2C_REG_CTL(alg_data)); 363 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | 364 mcntrl_drmie | mcntrl_daie); 365 iowrite32(ctl, I2C_REG_CTL(alg_data)); 366 367 /* Kill timer. */ 368 del_timer_sync(&alg_data->mif.timer); 369 complete(&alg_data->mif.complete); 370 } 371 } 372 373 dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n", 374 __func__, ioread32(I2C_REG_STS(alg_data))); 375 376 return 0; 377 } 378 379 static irqreturn_t i2c_pnx_interrupt(int irq, void *dev_id) 380 { 381 struct i2c_pnx_algo_data *alg_data = dev_id; 382 u32 stat, ctl; 383 384 dev_dbg(&alg_data->adapter.dev, 385 "%s(): mstat = %x mctrl = %x, mode = %d\n", 386 __func__, 387 ioread32(I2C_REG_STS(alg_data)), 388 ioread32(I2C_REG_CTL(alg_data)), 389 alg_data->mif.mode); 390 stat = ioread32(I2C_REG_STS(alg_data)); 391 392 /* let's see what kind of event this is */ 393 if (stat & mstatus_afi) { 394 /* We lost arbitration in the midst of a transfer */ 395 alg_data->mif.ret = -EIO; 396 397 /* Disable master interrupts. */ 398 ctl = ioread32(I2C_REG_CTL(alg_data)); 399 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | 400 mcntrl_drmie); 401 iowrite32(ctl, I2C_REG_CTL(alg_data)); 402 403 /* Stop timer, to prevent timeout. */ 404 del_timer_sync(&alg_data->mif.timer); 405 complete(&alg_data->mif.complete); 406 } else if (stat & mstatus_nai) { 407 /* Slave did not acknowledge, generate a STOP */ 408 dev_dbg(&alg_data->adapter.dev, 409 "%s(): Slave did not acknowledge, generating a STOP.\n", 410 __func__); 411 i2c_pnx_stop(alg_data); 412 413 /* Disable master interrupts. */ 414 ctl = ioread32(I2C_REG_CTL(alg_data)); 415 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | 416 mcntrl_drmie); 417 iowrite32(ctl, I2C_REG_CTL(alg_data)); 418 419 /* Our return value. */ 420 alg_data->mif.ret = -EIO; 421 422 /* Stop timer, to prevent timeout. */ 423 del_timer_sync(&alg_data->mif.timer); 424 complete(&alg_data->mif.complete); 425 } else { 426 /* 427 * Two options: 428 * - Master Tx needs data. 429 * - There is data in the Rx-fifo 430 * The latter is only the case if we have requested for data, 431 * via a dummy write. (See 'i2c_pnx_master_rcv'.) 432 * We therefore check, as a sanity check, whether that interrupt 433 * has been enabled. 434 */ 435 if ((stat & mstatus_drmi) || !(stat & mstatus_rfe)) { 436 if (alg_data->mif.mode == I2C_SMBUS_WRITE) { 437 i2c_pnx_master_xmit(alg_data); 438 } else if (alg_data->mif.mode == I2C_SMBUS_READ) { 439 i2c_pnx_master_rcv(alg_data); 440 } 441 } 442 } 443 444 /* Clear TDI and AFI bits */ 445 stat = ioread32(I2C_REG_STS(alg_data)); 446 iowrite32(stat | mstatus_tdi | mstatus_afi, I2C_REG_STS(alg_data)); 447 448 dev_dbg(&alg_data->adapter.dev, 449 "%s(): exiting, stat = %x ctrl = %x.\n", 450 __func__, ioread32(I2C_REG_STS(alg_data)), 451 ioread32(I2C_REG_CTL(alg_data))); 452 453 return IRQ_HANDLED; 454 } 455 456 static void i2c_pnx_timeout(struct timer_list *t) 457 { 458 struct i2c_pnx_algo_data *alg_data = from_timer(alg_data, t, mif.timer); 459 u32 ctl; 460 461 dev_err(&alg_data->adapter.dev, 462 "Master timed out. stat = %04x, cntrl = %04x. Resetting master...\n", 463 ioread32(I2C_REG_STS(alg_data)), 464 ioread32(I2C_REG_CTL(alg_data))); 465 466 /* Reset master and disable interrupts */ 467 ctl = ioread32(I2C_REG_CTL(alg_data)); 468 ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie | mcntrl_drmie); 469 iowrite32(ctl, I2C_REG_CTL(alg_data)); 470 471 ctl |= mcntrl_reset; 472 iowrite32(ctl, I2C_REG_CTL(alg_data)); 473 wait_reset(alg_data); 474 alg_data->mif.ret = -EIO; 475 complete(&alg_data->mif.complete); 476 } 477 478 static inline void bus_reset_if_active(struct i2c_pnx_algo_data *alg_data) 479 { 480 u32 stat; 481 482 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_active) { 483 dev_err(&alg_data->adapter.dev, 484 "%s: Bus is still active after xfer. Reset it...\n", 485 alg_data->adapter.name); 486 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, 487 I2C_REG_CTL(alg_data)); 488 wait_reset(alg_data); 489 } else if (!(stat & mstatus_rfe) || !(stat & mstatus_tfe)) { 490 /* If there is data in the fifo's after transfer, 491 * flush fifo's by reset. 492 */ 493 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, 494 I2C_REG_CTL(alg_data)); 495 wait_reset(alg_data); 496 } else if (stat & mstatus_nai) { 497 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset, 498 I2C_REG_CTL(alg_data)); 499 wait_reset(alg_data); 500 } 501 } 502 503 /** 504 * i2c_pnx_xfer - generic transfer entry point 505 * @adap: pointer to I2C adapter structure 506 * @msgs: array of messages 507 * @num: number of messages 508 * 509 * Initiates the transfer 510 */ 511 static int 512 i2c_pnx_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 513 { 514 struct i2c_msg *pmsg; 515 int rc = 0, completed = 0, i; 516 struct i2c_pnx_algo_data *alg_data = adap->algo_data; 517 u32 stat; 518 519 dev_dbg(&alg_data->adapter.dev, 520 "%s(): entering: %d messages, stat = %04x.\n", 521 __func__, num, ioread32(I2C_REG_STS(alg_data))); 522 523 bus_reset_if_active(alg_data); 524 525 /* Process transactions in a loop. */ 526 for (i = 0; rc >= 0 && i < num; i++) { 527 u8 addr; 528 529 pmsg = &msgs[i]; 530 addr = pmsg->addr; 531 532 if (pmsg->flags & I2C_M_TEN) { 533 dev_err(&alg_data->adapter.dev, 534 "%s: 10 bits addr not supported!\n", 535 alg_data->adapter.name); 536 rc = -EINVAL; 537 break; 538 } 539 540 alg_data->mif.buf = pmsg->buf; 541 alg_data->mif.len = pmsg->len; 542 alg_data->mif.order = pmsg->len; 543 alg_data->mif.mode = (pmsg->flags & I2C_M_RD) ? 544 I2C_SMBUS_READ : I2C_SMBUS_WRITE; 545 alg_data->mif.ret = 0; 546 alg_data->last = (i == num - 1); 547 548 dev_dbg(&alg_data->adapter.dev, "%s(): mode %d, %d bytes\n", 549 __func__, alg_data->mif.mode, alg_data->mif.len); 550 551 i2c_pnx_arm_timer(alg_data); 552 553 /* initialize the completion var */ 554 init_completion(&alg_data->mif.complete); 555 556 /* Enable master interrupt */ 557 iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_afie | 558 mcntrl_naie | mcntrl_drmie, 559 I2C_REG_CTL(alg_data)); 560 561 /* Put start-code and slave-address on the bus. */ 562 rc = i2c_pnx_start(addr, alg_data); 563 if (rc < 0) 564 break; 565 566 /* Wait for completion */ 567 wait_for_completion(&alg_data->mif.complete); 568 569 if (!(rc = alg_data->mif.ret)) 570 completed++; 571 dev_dbg(&alg_data->adapter.dev, 572 "%s(): Complete, return code = %d.\n", 573 __func__, rc); 574 575 /* Clear TDI and AFI bits in case they are set. */ 576 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_tdi) { 577 dev_dbg(&alg_data->adapter.dev, 578 "%s: TDI still set... clearing now.\n", 579 alg_data->adapter.name); 580 iowrite32(stat, I2C_REG_STS(alg_data)); 581 } 582 if ((stat = ioread32(I2C_REG_STS(alg_data))) & mstatus_afi) { 583 dev_dbg(&alg_data->adapter.dev, 584 "%s: AFI still set... clearing now.\n", 585 alg_data->adapter.name); 586 iowrite32(stat, I2C_REG_STS(alg_data)); 587 } 588 } 589 590 bus_reset_if_active(alg_data); 591 592 /* Cleanup to be sure... */ 593 alg_data->mif.buf = NULL; 594 alg_data->mif.len = 0; 595 alg_data->mif.order = 0; 596 597 dev_dbg(&alg_data->adapter.dev, "%s(): exiting, stat = %x\n", 598 __func__, ioread32(I2C_REG_STS(alg_data))); 599 600 if (completed != num) 601 return ((rc < 0) ? rc : -EREMOTEIO); 602 603 return num; 604 } 605 606 static u32 i2c_pnx_func(struct i2c_adapter *adapter) 607 { 608 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; 609 } 610 611 static const struct i2c_algorithm pnx_algorithm = { 612 .master_xfer = i2c_pnx_xfer, 613 .functionality = i2c_pnx_func, 614 }; 615 616 static int i2c_pnx_controller_suspend(struct device *dev) 617 { 618 struct i2c_pnx_algo_data *alg_data = dev_get_drvdata(dev); 619 620 clk_disable_unprepare(alg_data->clk); 621 622 return 0; 623 } 624 625 static int i2c_pnx_controller_resume(struct device *dev) 626 { 627 struct i2c_pnx_algo_data *alg_data = dev_get_drvdata(dev); 628 629 return clk_prepare_enable(alg_data->clk); 630 } 631 632 static DEFINE_SIMPLE_DEV_PM_OPS(i2c_pnx_pm, 633 i2c_pnx_controller_suspend, 634 i2c_pnx_controller_resume); 635 636 static int i2c_pnx_probe(struct platform_device *pdev) 637 { 638 unsigned long tmp; 639 int ret = 0; 640 struct i2c_pnx_algo_data *alg_data; 641 unsigned long freq; 642 struct resource *res; 643 u32 speed = I2C_PNX_SPEED_KHZ_DEFAULT * 1000; 644 645 alg_data = devm_kzalloc(&pdev->dev, sizeof(*alg_data), GFP_KERNEL); 646 if (!alg_data) 647 return -ENOMEM; 648 649 platform_set_drvdata(pdev, alg_data); 650 651 alg_data->adapter.dev.parent = &pdev->dev; 652 alg_data->adapter.algo = &pnx_algorithm; 653 alg_data->adapter.algo_data = alg_data; 654 alg_data->adapter.nr = pdev->id; 655 656 alg_data->timeout = I2C_PNX_TIMEOUT_DEFAULT; 657 #ifdef CONFIG_OF 658 alg_data->adapter.dev.of_node = of_node_get(pdev->dev.of_node); 659 if (pdev->dev.of_node) { 660 of_property_read_u32(pdev->dev.of_node, "clock-frequency", 661 &speed); 662 /* 663 * At this point, it is planned to add an OF timeout property. 664 * As soon as there is a consensus about how to call and handle 665 * this, sth. like the following can be put here: 666 * 667 * of_property_read_u32(pdev->dev.of_node, "timeout", 668 * &alg_data->timeout); 669 */ 670 } 671 #endif 672 alg_data->clk = devm_clk_get(&pdev->dev, NULL); 673 if (IS_ERR(alg_data->clk)) 674 return PTR_ERR(alg_data->clk); 675 676 timer_setup(&alg_data->mif.timer, i2c_pnx_timeout, 0); 677 678 snprintf(alg_data->adapter.name, sizeof(alg_data->adapter.name), 679 "%s", pdev->name); 680 681 /* Register I/O resource */ 682 alg_data->ioaddr = devm_platform_get_and_ioremap_resource(pdev, 0, &res); 683 if (IS_ERR(alg_data->ioaddr)) 684 return PTR_ERR(alg_data->ioaddr); 685 686 ret = clk_prepare_enable(alg_data->clk); 687 if (ret) 688 return ret; 689 690 freq = clk_get_rate(alg_data->clk); 691 692 /* 693 * Clock Divisor High This value is the number of system clocks 694 * the serial clock (SCL) will be high. 695 * For example, if the system clock period is 50 ns and the maximum 696 * desired serial period is 10000 ns (100 kHz), then CLKHI would be 697 * set to 0.5*(f_sys/f_i2c)-2=0.5*(20e6/100e3)-2=98. The actual value 698 * programmed into CLKHI will vary from this slightly due to 699 * variations in the output pad's rise and fall times as well as 700 * the deglitching filter length. 701 */ 702 703 tmp = (freq / speed) / 2 - 2; 704 if (tmp > 0x3FF) 705 tmp = 0x3FF; 706 iowrite32(tmp, I2C_REG_CKH(alg_data)); 707 iowrite32(tmp, I2C_REG_CKL(alg_data)); 708 709 iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data)); 710 if (wait_reset(alg_data)) { 711 ret = -ENODEV; 712 goto out_clock; 713 } 714 init_completion(&alg_data->mif.complete); 715 716 alg_data->irq = platform_get_irq(pdev, 0); 717 if (alg_data->irq < 0) { 718 ret = alg_data->irq; 719 goto out_clock; 720 } 721 ret = devm_request_irq(&pdev->dev, alg_data->irq, i2c_pnx_interrupt, 722 0, pdev->name, alg_data); 723 if (ret) 724 goto out_clock; 725 726 /* Register this adapter with the I2C subsystem */ 727 ret = i2c_add_numbered_adapter(&alg_data->adapter); 728 if (ret < 0) 729 goto out_clock; 730 731 dev_dbg(&pdev->dev, "%s: Master at %pap, irq %d.\n", 732 alg_data->adapter.name, &res->start, alg_data->irq); 733 734 return 0; 735 736 out_clock: 737 clk_disable_unprepare(alg_data->clk); 738 return ret; 739 } 740 741 static void i2c_pnx_remove(struct platform_device *pdev) 742 { 743 struct i2c_pnx_algo_data *alg_data = platform_get_drvdata(pdev); 744 745 i2c_del_adapter(&alg_data->adapter); 746 clk_disable_unprepare(alg_data->clk); 747 } 748 749 #ifdef CONFIG_OF 750 static const struct of_device_id i2c_pnx_of_match[] = { 751 { .compatible = "nxp,pnx-i2c" }, 752 { }, 753 }; 754 MODULE_DEVICE_TABLE(of, i2c_pnx_of_match); 755 #endif 756 757 static struct platform_driver i2c_pnx_driver = { 758 .driver = { 759 .name = "pnx-i2c", 760 .of_match_table = of_match_ptr(i2c_pnx_of_match), 761 .pm = pm_sleep_ptr(&i2c_pnx_pm), 762 }, 763 .probe = i2c_pnx_probe, 764 .remove_new = i2c_pnx_remove, 765 }; 766 767 static int __init i2c_adap_pnx_init(void) 768 { 769 return platform_driver_register(&i2c_pnx_driver); 770 } 771 772 static void __exit i2c_adap_pnx_exit(void) 773 { 774 platform_driver_unregister(&i2c_pnx_driver); 775 } 776 777 MODULE_AUTHOR("Vitaly Wool"); 778 MODULE_AUTHOR("Dennis Kovalev <source@mvista.com>"); 779 MODULE_DESCRIPTION("I2C driver for Philips IP3204-based I2C busses"); 780 MODULE_LICENSE("GPL"); 781 MODULE_ALIAS("platform:pnx-i2c"); 782 783 /* We need to make sure I2C is initialized before USB */ 784 subsys_initcall(i2c_adap_pnx_init); 785 module_exit(i2c_adap_pnx_exit); 786