1 /* 2 * (C) Copyright 2003-2004 3 * Humboldt Solutions Ltd, adrian@humboldt.co.uk. 4 5 * This is a combined i2c adapter and algorithm driver for the 6 * MPC107/Tsi107 PowerPC northbridge and processors that include 7 * the same I2C unit (8240, 8245, 85xx). 8 * 9 * Release 0.8 10 * 11 * This file is licensed under the terms of the GNU General Public 12 * License version 2. This program is licensed "as is" without any 13 * warranty of any kind, whether express or implied. 14 */ 15 16 #include <linux/kernel.h> 17 #include <linux/module.h> 18 #include <linux/sched/signal.h> 19 #include <linux/of_address.h> 20 #include <linux/of_irq.h> 21 #include <linux/of_platform.h> 22 #include <linux/slab.h> 23 24 #include <linux/clk.h> 25 #include <linux/io.h> 26 #include <linux/fsl_devices.h> 27 #include <linux/i2c.h> 28 #include <linux/interrupt.h> 29 #include <linux/delay.h> 30 31 #include <asm/mpc52xx.h> 32 #include <asm/mpc85xx.h> 33 #include <sysdev/fsl_soc.h> 34 35 #define DRV_NAME "mpc-i2c" 36 37 #define MPC_I2C_CLOCK_LEGACY 0 38 #define MPC_I2C_CLOCK_PRESERVE (~0U) 39 40 #define MPC_I2C_FDR 0x04 41 #define MPC_I2C_CR 0x08 42 #define MPC_I2C_SR 0x0c 43 #define MPC_I2C_DR 0x10 44 #define MPC_I2C_DFSRR 0x14 45 46 #define CCR_MEN 0x80 47 #define CCR_MIEN 0x40 48 #define CCR_MSTA 0x20 49 #define CCR_MTX 0x10 50 #define CCR_TXAK 0x08 51 #define CCR_RSTA 0x04 52 53 #define CSR_MCF 0x80 54 #define CSR_MAAS 0x40 55 #define CSR_MBB 0x20 56 #define CSR_MAL 0x10 57 #define CSR_SRW 0x04 58 #define CSR_MIF 0x02 59 #define CSR_RXAK 0x01 60 61 struct mpc_i2c { 62 struct device *dev; 63 void __iomem *base; 64 u32 interrupt; 65 wait_queue_head_t queue; 66 struct i2c_adapter adap; 67 int irq; 68 u32 real_clk; 69 #ifdef CONFIG_PM_SLEEP 70 u8 fdr, dfsrr; 71 #endif 72 struct clk *clk_per; 73 }; 74 75 struct mpc_i2c_divider { 76 u16 divider; 77 u16 fdr; /* including dfsrr */ 78 }; 79 80 struct mpc_i2c_data { 81 void (*setup)(struct device_node *node, struct mpc_i2c *i2c, 82 u32 clock, u32 prescaler); 83 u32 prescaler; 84 }; 85 86 static inline void writeccr(struct mpc_i2c *i2c, u32 x) 87 { 88 writeb(x, i2c->base + MPC_I2C_CR); 89 } 90 91 static irqreturn_t mpc_i2c_isr(int irq, void *dev_id) 92 { 93 struct mpc_i2c *i2c = dev_id; 94 if (readb(i2c->base + MPC_I2C_SR) & CSR_MIF) { 95 /* Read again to allow register to stabilise */ 96 i2c->interrupt = readb(i2c->base + MPC_I2C_SR); 97 writeb(0, i2c->base + MPC_I2C_SR); 98 wake_up(&i2c->queue); 99 return IRQ_HANDLED; 100 } 101 return IRQ_NONE; 102 } 103 104 /* Sometimes 9th clock pulse isn't generated, and slave doesn't release 105 * the bus, because it wants to send ACK. 106 * Following sequence of enabling/disabling and sending start/stop generates 107 * the 9 pulses, so it's all OK. 108 */ 109 static void mpc_i2c_fixup(struct mpc_i2c *i2c) 110 { 111 int k; 112 u32 delay_val = 1000000 / i2c->real_clk + 1; 113 114 if (delay_val < 2) 115 delay_val = 2; 116 117 for (k = 9; k; k--) { 118 writeccr(i2c, 0); 119 writeccr(i2c, CCR_MSTA | CCR_MTX | CCR_MEN); 120 readb(i2c->base + MPC_I2C_DR); 121 writeccr(i2c, CCR_MEN); 122 udelay(delay_val << 1); 123 } 124 } 125 126 static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing) 127 { 128 unsigned long orig_jiffies = jiffies; 129 u32 cmd_err; 130 int result = 0; 131 132 if (!i2c->irq) { 133 while (!(readb(i2c->base + MPC_I2C_SR) & CSR_MIF)) { 134 schedule(); 135 if (time_after(jiffies, orig_jiffies + timeout)) { 136 dev_dbg(i2c->dev, "timeout\n"); 137 writeccr(i2c, 0); 138 result = -ETIMEDOUT; 139 break; 140 } 141 } 142 cmd_err = readb(i2c->base + MPC_I2C_SR); 143 writeb(0, i2c->base + MPC_I2C_SR); 144 } else { 145 /* Interrupt mode */ 146 result = wait_event_timeout(i2c->queue, 147 (i2c->interrupt & CSR_MIF), timeout); 148 149 if (unlikely(!(i2c->interrupt & CSR_MIF))) { 150 dev_dbg(i2c->dev, "wait timeout\n"); 151 writeccr(i2c, 0); 152 result = -ETIMEDOUT; 153 } 154 155 cmd_err = i2c->interrupt; 156 i2c->interrupt = 0; 157 } 158 159 if (result < 0) 160 return result; 161 162 if (!(cmd_err & CSR_MCF)) { 163 dev_dbg(i2c->dev, "unfinished\n"); 164 return -EIO; 165 } 166 167 if (cmd_err & CSR_MAL) { 168 dev_dbg(i2c->dev, "MAL\n"); 169 return -EAGAIN; 170 } 171 172 if (writing && (cmd_err & CSR_RXAK)) { 173 dev_dbg(i2c->dev, "No RXAK\n"); 174 /* generate stop */ 175 writeccr(i2c, CCR_MEN); 176 return -ENXIO; 177 } 178 return 0; 179 } 180 181 #if defined(CONFIG_PPC_MPC52xx) || defined(CONFIG_PPC_MPC512x) 182 static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] = { 183 {20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23}, 184 {28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02}, 185 {36, 0x26}, {40, 0x27}, {44, 0x04}, {48, 0x28}, 186 {52, 0x63}, {56, 0x29}, {60, 0x41}, {64, 0x2a}, 187 {68, 0x07}, {72, 0x2b}, {80, 0x2c}, {88, 0x09}, 188 {96, 0x2d}, {104, 0x0a}, {112, 0x2e}, {120, 0x81}, 189 {128, 0x2f}, {136, 0x47}, {144, 0x0c}, {160, 0x30}, 190 {176, 0x49}, {192, 0x31}, {208, 0x4a}, {224, 0x32}, 191 {240, 0x0f}, {256, 0x33}, {272, 0x87}, {288, 0x10}, 192 {320, 0x34}, {352, 0x89}, {384, 0x35}, {416, 0x8a}, 193 {448, 0x36}, {480, 0x13}, {512, 0x37}, {576, 0x14}, 194 {640, 0x38}, {768, 0x39}, {896, 0x3a}, {960, 0x17}, 195 {1024, 0x3b}, {1152, 0x18}, {1280, 0x3c}, {1536, 0x3d}, 196 {1792, 0x3e}, {1920, 0x1b}, {2048, 0x3f}, {2304, 0x1c}, 197 {2560, 0x1d}, {3072, 0x1e}, {3584, 0x7e}, {3840, 0x1f}, 198 {4096, 0x7f}, {4608, 0x5c}, {5120, 0x5d}, {6144, 0x5e}, 199 {7168, 0xbe}, {7680, 0x5f}, {8192, 0xbf}, {9216, 0x9c}, 200 {10240, 0x9d}, {12288, 0x9e}, {15360, 0x9f} 201 }; 202 203 static int mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock, 204 int prescaler, u32 *real_clk) 205 { 206 const struct mpc_i2c_divider *div = NULL; 207 unsigned int pvr = mfspr(SPRN_PVR); 208 u32 divider; 209 int i; 210 211 if (clock == MPC_I2C_CLOCK_LEGACY) { 212 /* see below - default fdr = 0x3f -> div = 2048 */ 213 *real_clk = mpc5xxx_get_bus_frequency(node) / 2048; 214 return -EINVAL; 215 } 216 217 /* Determine divider value */ 218 divider = mpc5xxx_get_bus_frequency(node) / clock; 219 220 /* 221 * We want to choose an FDR/DFSR that generates an I2C bus speed that 222 * is equal to or lower than the requested speed. 223 */ 224 for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_52xx); i++) { 225 div = &mpc_i2c_dividers_52xx[i]; 226 /* Old MPC5200 rev A CPUs do not support the high bits */ 227 if (div->fdr & 0xc0 && pvr == 0x80822011) 228 continue; 229 if (div->divider >= divider) 230 break; 231 } 232 233 *real_clk = mpc5xxx_get_bus_frequency(node) / div->divider; 234 return (int)div->fdr; 235 } 236 237 static void mpc_i2c_setup_52xx(struct device_node *node, 238 struct mpc_i2c *i2c, 239 u32 clock, u32 prescaler) 240 { 241 int ret, fdr; 242 243 if (clock == MPC_I2C_CLOCK_PRESERVE) { 244 dev_dbg(i2c->dev, "using fdr %d\n", 245 readb(i2c->base + MPC_I2C_FDR)); 246 return; 247 } 248 249 ret = mpc_i2c_get_fdr_52xx(node, clock, prescaler, &i2c->real_clk); 250 fdr = (ret >= 0) ? ret : 0x3f; /* backward compatibility */ 251 252 writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR); 253 254 if (ret >= 0) 255 dev_info(i2c->dev, "clock %u Hz (fdr=%d)\n", i2c->real_clk, 256 fdr); 257 } 258 #else /* !(CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x) */ 259 static void mpc_i2c_setup_52xx(struct device_node *node, 260 struct mpc_i2c *i2c, 261 u32 clock, u32 prescaler) 262 { 263 } 264 #endif /* CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x */ 265 266 #ifdef CONFIG_PPC_MPC512x 267 static void mpc_i2c_setup_512x(struct device_node *node, 268 struct mpc_i2c *i2c, 269 u32 clock, u32 prescaler) 270 { 271 struct device_node *node_ctrl; 272 void __iomem *ctrl; 273 const u32 *pval; 274 u32 idx; 275 276 /* Enable I2C interrupts for mpc5121 */ 277 node_ctrl = of_find_compatible_node(NULL, NULL, 278 "fsl,mpc5121-i2c-ctrl"); 279 if (node_ctrl) { 280 ctrl = of_iomap(node_ctrl, 0); 281 if (ctrl) { 282 /* Interrupt enable bits for i2c-0/1/2: bit 24/26/28 */ 283 pval = of_get_property(node, "reg", NULL); 284 idx = (*pval & 0xff) / 0x20; 285 setbits32(ctrl, 1 << (24 + idx * 2)); 286 iounmap(ctrl); 287 } 288 of_node_put(node_ctrl); 289 } 290 291 /* The clock setup for the 52xx works also fine for the 512x */ 292 mpc_i2c_setup_52xx(node, i2c, clock, prescaler); 293 } 294 #else /* CONFIG_PPC_MPC512x */ 295 static void mpc_i2c_setup_512x(struct device_node *node, 296 struct mpc_i2c *i2c, 297 u32 clock, u32 prescaler) 298 { 299 } 300 #endif /* CONFIG_PPC_MPC512x */ 301 302 #ifdef CONFIG_FSL_SOC 303 static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] = { 304 {160, 0x0120}, {192, 0x0121}, {224, 0x0122}, {256, 0x0123}, 305 {288, 0x0100}, {320, 0x0101}, {352, 0x0601}, {384, 0x0102}, 306 {416, 0x0602}, {448, 0x0126}, {480, 0x0103}, {512, 0x0127}, 307 {544, 0x0b03}, {576, 0x0104}, {608, 0x1603}, {640, 0x0105}, 308 {672, 0x2003}, {704, 0x0b05}, {736, 0x2b03}, {768, 0x0106}, 309 {800, 0x3603}, {832, 0x0b06}, {896, 0x012a}, {960, 0x0107}, 310 {1024, 0x012b}, {1088, 0x1607}, {1152, 0x0108}, {1216, 0x2b07}, 311 {1280, 0x0109}, {1408, 0x1609}, {1536, 0x010a}, {1664, 0x160a}, 312 {1792, 0x012e}, {1920, 0x010b}, {2048, 0x012f}, {2176, 0x2b0b}, 313 {2304, 0x010c}, {2560, 0x010d}, {2816, 0x2b0d}, {3072, 0x010e}, 314 {3328, 0x2b0e}, {3584, 0x0132}, {3840, 0x010f}, {4096, 0x0133}, 315 {4608, 0x0110}, {5120, 0x0111}, {6144, 0x0112}, {7168, 0x0136}, 316 {7680, 0x0113}, {8192, 0x0137}, {9216, 0x0114}, {10240, 0x0115}, 317 {12288, 0x0116}, {14336, 0x013a}, {15360, 0x0117}, {16384, 0x013b}, 318 {18432, 0x0118}, {20480, 0x0119}, {24576, 0x011a}, {28672, 0x013e}, 319 {30720, 0x011b}, {32768, 0x013f}, {36864, 0x011c}, {40960, 0x011d}, 320 {49152, 0x011e}, {61440, 0x011f} 321 }; 322 323 static u32 mpc_i2c_get_sec_cfg_8xxx(void) 324 { 325 struct device_node *node = NULL; 326 u32 __iomem *reg; 327 u32 val = 0; 328 329 node = of_find_node_by_name(NULL, "global-utilities"); 330 if (node) { 331 const u32 *prop = of_get_property(node, "reg", NULL); 332 if (prop) { 333 /* 334 * Map and check POR Device Status Register 2 335 * (PORDEVSR2) at 0xE0014 336 */ 337 reg = ioremap(get_immrbase() + *prop + 0x14, 0x4); 338 if (!reg) 339 printk(KERN_ERR 340 "Error: couldn't map PORDEVSR2\n"); 341 else 342 val = in_be32(reg) & 0x00000080; /* sec-cfg */ 343 iounmap(reg); 344 } 345 } 346 of_node_put(node); 347 348 return val; 349 } 350 351 static u32 mpc_i2c_get_prescaler_8xxx(void) 352 { 353 /* mpc83xx and mpc82xx all have prescaler 1 */ 354 u32 prescaler = 1; 355 356 /* mpc85xx */ 357 if (pvr_version_is(PVR_VER_E500V1) || pvr_version_is(PVR_VER_E500V2) 358 || pvr_version_is(PVR_VER_E500MC) 359 || pvr_version_is(PVR_VER_E5500) 360 || pvr_version_is(PVR_VER_E6500)) { 361 unsigned int svr = mfspr(SPRN_SVR); 362 363 if ((SVR_SOC_VER(svr) == SVR_8540) 364 || (SVR_SOC_VER(svr) == SVR_8541) 365 || (SVR_SOC_VER(svr) == SVR_8560) 366 || (SVR_SOC_VER(svr) == SVR_8555) 367 || (SVR_SOC_VER(svr) == SVR_8610)) 368 /* the above 85xx SoCs have prescaler 1 */ 369 prescaler = 1; 370 else 371 /* all the other 85xx have prescaler 2 */ 372 prescaler = 2; 373 } 374 375 return prescaler; 376 } 377 378 static int mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock, 379 u32 prescaler, u32 *real_clk) 380 { 381 const struct mpc_i2c_divider *div = NULL; 382 u32 divider; 383 int i; 384 385 if (clock == MPC_I2C_CLOCK_LEGACY) { 386 /* see below - default fdr = 0x1031 -> div = 16 * 3072 */ 387 *real_clk = fsl_get_sys_freq() / prescaler / (16 * 3072); 388 return -EINVAL; 389 } 390 391 /* Determine proper divider value */ 392 if (of_device_is_compatible(node, "fsl,mpc8544-i2c")) 393 prescaler = mpc_i2c_get_sec_cfg_8xxx() ? 3 : 2; 394 if (!prescaler) 395 prescaler = mpc_i2c_get_prescaler_8xxx(); 396 397 divider = fsl_get_sys_freq() / clock / prescaler; 398 399 pr_debug("I2C: src_clock=%d clock=%d divider=%d\n", 400 fsl_get_sys_freq(), clock, divider); 401 402 /* 403 * We want to choose an FDR/DFSR that generates an I2C bus speed that 404 * is equal to or lower than the requested speed. 405 */ 406 for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_8xxx); i++) { 407 div = &mpc_i2c_dividers_8xxx[i]; 408 if (div->divider >= divider) 409 break; 410 } 411 412 *real_clk = fsl_get_sys_freq() / prescaler / div->divider; 413 return div ? (int)div->fdr : -EINVAL; 414 } 415 416 static void mpc_i2c_setup_8xxx(struct device_node *node, 417 struct mpc_i2c *i2c, 418 u32 clock, u32 prescaler) 419 { 420 int ret, fdr; 421 422 if (clock == MPC_I2C_CLOCK_PRESERVE) { 423 dev_dbg(i2c->dev, "using dfsrr %d, fdr %d\n", 424 readb(i2c->base + MPC_I2C_DFSRR), 425 readb(i2c->base + MPC_I2C_FDR)); 426 return; 427 } 428 429 ret = mpc_i2c_get_fdr_8xxx(node, clock, prescaler, &i2c->real_clk); 430 fdr = (ret >= 0) ? ret : 0x1031; /* backward compatibility */ 431 432 writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR); 433 writeb((fdr >> 8) & 0xff, i2c->base + MPC_I2C_DFSRR); 434 435 if (ret >= 0) 436 dev_info(i2c->dev, "clock %d Hz (dfsrr=%d fdr=%d)\n", 437 i2c->real_clk, fdr >> 8, fdr & 0xff); 438 } 439 440 #else /* !CONFIG_FSL_SOC */ 441 static void mpc_i2c_setup_8xxx(struct device_node *node, 442 struct mpc_i2c *i2c, 443 u32 clock, u32 prescaler) 444 { 445 } 446 #endif /* CONFIG_FSL_SOC */ 447 448 static void mpc_i2c_start(struct mpc_i2c *i2c) 449 { 450 /* Clear arbitration */ 451 writeb(0, i2c->base + MPC_I2C_SR); 452 /* Start with MEN */ 453 writeccr(i2c, CCR_MEN); 454 } 455 456 static void mpc_i2c_stop(struct mpc_i2c *i2c) 457 { 458 writeccr(i2c, CCR_MEN); 459 } 460 461 static int mpc_write(struct mpc_i2c *i2c, int target, 462 const u8 *data, int length, int restart) 463 { 464 int i, result; 465 unsigned timeout = i2c->adap.timeout; 466 u32 flags = restart ? CCR_RSTA : 0; 467 468 /* Start as master */ 469 writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags); 470 /* Write target byte */ 471 writeb((target << 1), i2c->base + MPC_I2C_DR); 472 473 result = i2c_wait(i2c, timeout, 1); 474 if (result < 0) 475 return result; 476 477 for (i = 0; i < length; i++) { 478 /* Write data byte */ 479 writeb(data[i], i2c->base + MPC_I2C_DR); 480 481 result = i2c_wait(i2c, timeout, 1); 482 if (result < 0) 483 return result; 484 } 485 486 return 0; 487 } 488 489 static int mpc_read(struct mpc_i2c *i2c, int target, 490 u8 *data, int length, int restart, bool recv_len) 491 { 492 unsigned timeout = i2c->adap.timeout; 493 int i, result; 494 u32 flags = restart ? CCR_RSTA : 0; 495 496 /* Switch to read - restart */ 497 writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags); 498 /* Write target address byte - this time with the read flag set */ 499 writeb((target << 1) | 1, i2c->base + MPC_I2C_DR); 500 501 result = i2c_wait(i2c, timeout, 1); 502 if (result < 0) 503 return result; 504 505 if (length) { 506 if (length == 1 && !recv_len) 507 writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK); 508 else 509 writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA); 510 /* Dummy read */ 511 readb(i2c->base + MPC_I2C_DR); 512 } 513 514 for (i = 0; i < length; i++) { 515 u8 byte; 516 517 result = i2c_wait(i2c, timeout, 0); 518 if (result < 0) 519 return result; 520 521 /* 522 * For block reads, we have to know the total length (1st byte) 523 * before we can determine if we are done. 524 */ 525 if (i || !recv_len) { 526 /* Generate txack on next to last byte */ 527 if (i == length - 2) 528 writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA 529 | CCR_TXAK); 530 /* Do not generate stop on last byte */ 531 if (i == length - 1) 532 writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA 533 | CCR_MTX); 534 } 535 536 byte = readb(i2c->base + MPC_I2C_DR); 537 538 /* 539 * Adjust length if first received byte is length. 540 * The length is 1 length byte plus actually data length 541 */ 542 if (i == 0 && recv_len) { 543 if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX) 544 return -EPROTO; 545 length += byte; 546 /* 547 * For block reads, generate txack here if data length 548 * is 1 byte (total length is 2 bytes). 549 */ 550 if (length == 2) 551 writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA 552 | CCR_TXAK); 553 } 554 data[i] = byte; 555 } 556 557 return length; 558 } 559 560 static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 561 { 562 struct i2c_msg *pmsg; 563 int i; 564 int ret = 0; 565 unsigned long orig_jiffies = jiffies; 566 struct mpc_i2c *i2c = i2c_get_adapdata(adap); 567 568 mpc_i2c_start(i2c); 569 570 /* Allow bus up to 1s to become not busy */ 571 while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) { 572 if (signal_pending(current)) { 573 dev_dbg(i2c->dev, "Interrupted\n"); 574 writeccr(i2c, 0); 575 return -EINTR; 576 } 577 if (time_after(jiffies, orig_jiffies + HZ)) { 578 u8 status = readb(i2c->base + MPC_I2C_SR); 579 580 dev_dbg(i2c->dev, "timeout\n"); 581 if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) { 582 writeb(status & ~CSR_MAL, 583 i2c->base + MPC_I2C_SR); 584 mpc_i2c_fixup(i2c); 585 } 586 return -EIO; 587 } 588 schedule(); 589 } 590 591 for (i = 0; ret >= 0 && i < num; i++) { 592 pmsg = &msgs[i]; 593 dev_dbg(i2c->dev, 594 "Doing %s %d bytes to 0x%02x - %d of %d messages\n", 595 pmsg->flags & I2C_M_RD ? "read" : "write", 596 pmsg->len, pmsg->addr, i + 1, num); 597 if (pmsg->flags & I2C_M_RD) { 598 bool recv_len = pmsg->flags & I2C_M_RECV_LEN; 599 600 ret = mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i, 601 recv_len); 602 if (recv_len && ret > 0) 603 pmsg->len = ret; 604 } else { 605 ret = 606 mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, i); 607 } 608 } 609 mpc_i2c_stop(i2c); /* Initiate STOP */ 610 orig_jiffies = jiffies; 611 /* Wait until STOP is seen, allow up to 1 s */ 612 while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) { 613 if (time_after(jiffies, orig_jiffies + HZ)) { 614 u8 status = readb(i2c->base + MPC_I2C_SR); 615 616 dev_dbg(i2c->dev, "timeout\n"); 617 if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) { 618 writeb(status & ~CSR_MAL, 619 i2c->base + MPC_I2C_SR); 620 mpc_i2c_fixup(i2c); 621 } 622 return -EIO; 623 } 624 cond_resched(); 625 } 626 return (ret < 0) ? ret : num; 627 } 628 629 static u32 mpc_functionality(struct i2c_adapter *adap) 630 { 631 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL 632 | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL; 633 } 634 635 static const struct i2c_algorithm mpc_algo = { 636 .master_xfer = mpc_xfer, 637 .functionality = mpc_functionality, 638 }; 639 640 static struct i2c_adapter mpc_ops = { 641 .owner = THIS_MODULE, 642 .algo = &mpc_algo, 643 .timeout = HZ, 644 }; 645 646 static const struct of_device_id mpc_i2c_of_match[]; 647 static int fsl_i2c_probe(struct platform_device *op) 648 { 649 const struct of_device_id *match; 650 struct mpc_i2c *i2c; 651 const u32 *prop; 652 u32 clock = MPC_I2C_CLOCK_LEGACY; 653 int result = 0; 654 int plen; 655 struct resource res; 656 struct clk *clk; 657 int err; 658 659 match = of_match_device(mpc_i2c_of_match, &op->dev); 660 if (!match) 661 return -EINVAL; 662 663 i2c = kzalloc(sizeof(*i2c), GFP_KERNEL); 664 if (!i2c) 665 return -ENOMEM; 666 667 i2c->dev = &op->dev; /* for debug and error output */ 668 669 init_waitqueue_head(&i2c->queue); 670 671 i2c->base = of_iomap(op->dev.of_node, 0); 672 if (!i2c->base) { 673 dev_err(i2c->dev, "failed to map controller\n"); 674 result = -ENOMEM; 675 goto fail_map; 676 } 677 678 i2c->irq = irq_of_parse_and_map(op->dev.of_node, 0); 679 if (i2c->irq) { /* no i2c->irq implies polling */ 680 result = request_irq(i2c->irq, mpc_i2c_isr, 681 IRQF_SHARED, "i2c-mpc", i2c); 682 if (result < 0) { 683 dev_err(i2c->dev, "failed to attach interrupt\n"); 684 goto fail_request; 685 } 686 } 687 688 /* 689 * enable clock for the I2C peripheral (non fatal), 690 * keep a reference upon successful allocation 691 */ 692 clk = devm_clk_get(&op->dev, NULL); 693 if (!IS_ERR(clk)) { 694 err = clk_prepare_enable(clk); 695 if (err) { 696 dev_err(&op->dev, "failed to enable clock\n"); 697 goto fail_request; 698 } else { 699 i2c->clk_per = clk; 700 } 701 } 702 703 if (of_get_property(op->dev.of_node, "fsl,preserve-clocking", NULL)) { 704 clock = MPC_I2C_CLOCK_PRESERVE; 705 } else { 706 prop = of_get_property(op->dev.of_node, "clock-frequency", 707 &plen); 708 if (prop && plen == sizeof(u32)) 709 clock = *prop; 710 } 711 712 if (match->data) { 713 const struct mpc_i2c_data *data = match->data; 714 data->setup(op->dev.of_node, i2c, clock, data->prescaler); 715 } else { 716 /* Backwards compatibility */ 717 if (of_get_property(op->dev.of_node, "dfsrr", NULL)) 718 mpc_i2c_setup_8xxx(op->dev.of_node, i2c, clock, 0); 719 } 720 721 prop = of_get_property(op->dev.of_node, "fsl,timeout", &plen); 722 if (prop && plen == sizeof(u32)) { 723 mpc_ops.timeout = *prop * HZ / 1000000; 724 if (mpc_ops.timeout < 5) 725 mpc_ops.timeout = 5; 726 } 727 dev_info(i2c->dev, "timeout %u us\n", mpc_ops.timeout * 1000000 / HZ); 728 729 platform_set_drvdata(op, i2c); 730 731 i2c->adap = mpc_ops; 732 of_address_to_resource(op->dev.of_node, 0, &res); 733 scnprintf(i2c->adap.name, sizeof(i2c->adap.name), 734 "MPC adapter at 0x%llx", (unsigned long long)res.start); 735 i2c_set_adapdata(&i2c->adap, i2c); 736 i2c->adap.dev.parent = &op->dev; 737 i2c->adap.dev.of_node = of_node_get(op->dev.of_node); 738 739 result = i2c_add_adapter(&i2c->adap); 740 if (result < 0) 741 goto fail_add; 742 743 return result; 744 745 fail_add: 746 if (i2c->clk_per) 747 clk_disable_unprepare(i2c->clk_per); 748 free_irq(i2c->irq, i2c); 749 fail_request: 750 irq_dispose_mapping(i2c->irq); 751 iounmap(i2c->base); 752 fail_map: 753 kfree(i2c); 754 return result; 755 }; 756 757 static int fsl_i2c_remove(struct platform_device *op) 758 { 759 struct mpc_i2c *i2c = platform_get_drvdata(op); 760 761 i2c_del_adapter(&i2c->adap); 762 763 if (i2c->clk_per) 764 clk_disable_unprepare(i2c->clk_per); 765 766 if (i2c->irq) 767 free_irq(i2c->irq, i2c); 768 769 irq_dispose_mapping(i2c->irq); 770 iounmap(i2c->base); 771 kfree(i2c); 772 return 0; 773 }; 774 775 #ifdef CONFIG_PM_SLEEP 776 static int mpc_i2c_suspend(struct device *dev) 777 { 778 struct mpc_i2c *i2c = dev_get_drvdata(dev); 779 780 i2c->fdr = readb(i2c->base + MPC_I2C_FDR); 781 i2c->dfsrr = readb(i2c->base + MPC_I2C_DFSRR); 782 783 return 0; 784 } 785 786 static int mpc_i2c_resume(struct device *dev) 787 { 788 struct mpc_i2c *i2c = dev_get_drvdata(dev); 789 790 writeb(i2c->fdr, i2c->base + MPC_I2C_FDR); 791 writeb(i2c->dfsrr, i2c->base + MPC_I2C_DFSRR); 792 793 return 0; 794 } 795 796 static SIMPLE_DEV_PM_OPS(mpc_i2c_pm_ops, mpc_i2c_suspend, mpc_i2c_resume); 797 #define MPC_I2C_PM_OPS (&mpc_i2c_pm_ops) 798 #else 799 #define MPC_I2C_PM_OPS NULL 800 #endif 801 802 static const struct mpc_i2c_data mpc_i2c_data_512x = { 803 .setup = mpc_i2c_setup_512x, 804 }; 805 806 static const struct mpc_i2c_data mpc_i2c_data_52xx = { 807 .setup = mpc_i2c_setup_52xx, 808 }; 809 810 static const struct mpc_i2c_data mpc_i2c_data_8313 = { 811 .setup = mpc_i2c_setup_8xxx, 812 }; 813 814 static const struct mpc_i2c_data mpc_i2c_data_8543 = { 815 .setup = mpc_i2c_setup_8xxx, 816 .prescaler = 2, 817 }; 818 819 static const struct mpc_i2c_data mpc_i2c_data_8544 = { 820 .setup = mpc_i2c_setup_8xxx, 821 .prescaler = 3, 822 }; 823 824 static const struct of_device_id mpc_i2c_of_match[] = { 825 {.compatible = "mpc5200-i2c", .data = &mpc_i2c_data_52xx, }, 826 {.compatible = "fsl,mpc5200b-i2c", .data = &mpc_i2c_data_52xx, }, 827 {.compatible = "fsl,mpc5200-i2c", .data = &mpc_i2c_data_52xx, }, 828 {.compatible = "fsl,mpc5121-i2c", .data = &mpc_i2c_data_512x, }, 829 {.compatible = "fsl,mpc8313-i2c", .data = &mpc_i2c_data_8313, }, 830 {.compatible = "fsl,mpc8543-i2c", .data = &mpc_i2c_data_8543, }, 831 {.compatible = "fsl,mpc8544-i2c", .data = &mpc_i2c_data_8544, }, 832 /* Backward compatibility */ 833 {.compatible = "fsl-i2c", }, 834 {}, 835 }; 836 MODULE_DEVICE_TABLE(of, mpc_i2c_of_match); 837 838 /* Structure for a device driver */ 839 static struct platform_driver mpc_i2c_driver = { 840 .probe = fsl_i2c_probe, 841 .remove = fsl_i2c_remove, 842 .driver = { 843 .name = DRV_NAME, 844 .of_match_table = mpc_i2c_of_match, 845 .pm = MPC_I2C_PM_OPS, 846 }, 847 }; 848 849 module_platform_driver(mpc_i2c_driver); 850 851 MODULE_AUTHOR("Adrian Cox <adrian@humboldt.co.uk>"); 852 MODULE_DESCRIPTION("I2C-Bus adapter for MPC107 bridge and " 853 "MPC824x/83xx/85xx/86xx/512x/52xx processors"); 854 MODULE_LICENSE("GPL"); 855