1 /* 2 * Copyright (C) 2002 Motorola GSG-China 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 2 7 * of the License, or (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 17 * USA. 18 * 19 * Author: 20 * Darius Augulis, Teltonika Inc. 21 * 22 * Desc.: 23 * Implementation of I2C Adapter/Algorithm Driver 24 * for I2C Bus integrated in Freescale i.MX/MXC processors 25 * 26 * Derived from Motorola GSG China I2C example driver 27 * 28 * Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de 29 * Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de 30 * Copyright (C) 2007 RightHand Technologies, Inc. 31 * Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt> 32 * 33 */ 34 35 /** Includes ******************************************************************* 36 *******************************************************************************/ 37 38 #include <linux/init.h> 39 #include <linux/kernel.h> 40 #include <linux/module.h> 41 #include <linux/errno.h> 42 #include <linux/err.h> 43 #include <linux/interrupt.h> 44 #include <linux/delay.h> 45 #include <linux/i2c.h> 46 #include <linux/io.h> 47 #include <linux/sched.h> 48 #include <linux/platform_device.h> 49 #include <linux/clk.h> 50 #include <linux/slab.h> 51 #include <linux/of.h> 52 #include <linux/of_device.h> 53 #include <linux/of_i2c.h> 54 #include <linux/platform_data/i2c-imx.h> 55 56 /** Defines ******************************************************************** 57 *******************************************************************************/ 58 59 /* This will be the driver name the kernel reports */ 60 #define DRIVER_NAME "imx-i2c" 61 62 /* Default value */ 63 #define IMX_I2C_BIT_RATE 100000 /* 100kHz */ 64 65 /* IMX I2C registers */ 66 #define IMX_I2C_IADR 0x00 /* i2c slave address */ 67 #define IMX_I2C_IFDR 0x04 /* i2c frequency divider */ 68 #define IMX_I2C_I2CR 0x08 /* i2c control */ 69 #define IMX_I2C_I2SR 0x0C /* i2c status */ 70 #define IMX_I2C_I2DR 0x10 /* i2c transfer data */ 71 72 /* Bits of IMX I2C registers */ 73 #define I2SR_RXAK 0x01 74 #define I2SR_IIF 0x02 75 #define I2SR_SRW 0x04 76 #define I2SR_IAL 0x10 77 #define I2SR_IBB 0x20 78 #define I2SR_IAAS 0x40 79 #define I2SR_ICF 0x80 80 #define I2CR_RSTA 0x04 81 #define I2CR_TXAK 0x08 82 #define I2CR_MTX 0x10 83 #define I2CR_MSTA 0x20 84 #define I2CR_IIEN 0x40 85 #define I2CR_IEN 0x80 86 87 /** Variables ****************************************************************** 88 *******************************************************************************/ 89 90 /* 91 * sorted list of clock divider, register value pairs 92 * taken from table 26-5, p.26-9, Freescale i.MX 93 * Integrated Portable System Processor Reference Manual 94 * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007 95 * 96 * Duplicated divider values removed from list 97 */ 98 99 static u16 __initdata i2c_clk_div[50][2] = { 100 { 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 }, 101 { 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 }, 102 { 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 }, 103 { 56, 0x29 }, { 60, 0x06 }, { 64, 0x2A }, { 72, 0x2B }, 104 { 80, 0x2C }, { 88, 0x09 }, { 96, 0x2D }, { 104, 0x0A }, 105 { 112, 0x2E }, { 128, 0x2F }, { 144, 0x0C }, { 160, 0x30 }, 106 { 192, 0x31 }, { 224, 0x32 }, { 240, 0x0F }, { 256, 0x33 }, 107 { 288, 0x10 }, { 320, 0x34 }, { 384, 0x35 }, { 448, 0x36 }, 108 { 480, 0x13 }, { 512, 0x37 }, { 576, 0x14 }, { 640, 0x38 }, 109 { 768, 0x39 }, { 896, 0x3A }, { 960, 0x17 }, { 1024, 0x3B }, 110 { 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E }, 111 { 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D }, 112 { 3072, 0x1E }, { 3840, 0x1F } 113 }; 114 115 enum imx_i2c_type { 116 IMX1_I2C, 117 IMX21_I2C, 118 }; 119 120 struct imx_i2c_struct { 121 struct i2c_adapter adapter; 122 struct clk *clk; 123 void __iomem *base; 124 wait_queue_head_t queue; 125 unsigned long i2csr; 126 unsigned int disable_delay; 127 int stopped; 128 unsigned int ifdr; /* IMX_I2C_IFDR */ 129 enum imx_i2c_type devtype; 130 }; 131 132 static struct platform_device_id imx_i2c_devtype[] = { 133 { 134 .name = "imx1-i2c", 135 .driver_data = IMX1_I2C, 136 }, { 137 .name = "imx21-i2c", 138 .driver_data = IMX21_I2C, 139 }, { 140 /* sentinel */ 141 } 142 }; 143 MODULE_DEVICE_TABLE(platform, imx_i2c_devtype); 144 145 static const struct of_device_id i2c_imx_dt_ids[] = { 146 { .compatible = "fsl,imx1-i2c", .data = &imx_i2c_devtype[IMX1_I2C], }, 147 { .compatible = "fsl,imx21-i2c", .data = &imx_i2c_devtype[IMX21_I2C], }, 148 { /* sentinel */ } 149 }; 150 MODULE_DEVICE_TABLE(of, i2c_imx_dt_ids); 151 152 static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx) 153 { 154 return i2c_imx->devtype == IMX1_I2C; 155 } 156 157 /** Functions for IMX I2C adapter driver *************************************** 158 *******************************************************************************/ 159 160 static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy) 161 { 162 unsigned long orig_jiffies = jiffies; 163 unsigned int temp; 164 165 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 166 167 while (1) { 168 temp = readb(i2c_imx->base + IMX_I2C_I2SR); 169 if (for_busy && (temp & I2SR_IBB)) 170 break; 171 if (!for_busy && !(temp & I2SR_IBB)) 172 break; 173 if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) { 174 dev_dbg(&i2c_imx->adapter.dev, 175 "<%s> I2C bus is busy\n", __func__); 176 return -ETIMEDOUT; 177 } 178 schedule(); 179 } 180 181 return 0; 182 } 183 184 static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx) 185 { 186 wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10); 187 188 if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) { 189 dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__); 190 return -ETIMEDOUT; 191 } 192 dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__); 193 i2c_imx->i2csr = 0; 194 return 0; 195 } 196 197 static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx) 198 { 199 if (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK) { 200 dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__); 201 return -EIO; /* No ACK */ 202 } 203 204 dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__); 205 return 0; 206 } 207 208 static int i2c_imx_start(struct imx_i2c_struct *i2c_imx) 209 { 210 unsigned int temp = 0; 211 int result; 212 213 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 214 215 clk_prepare_enable(i2c_imx->clk); 216 writeb(i2c_imx->ifdr, i2c_imx->base + IMX_I2C_IFDR); 217 /* Enable I2C controller */ 218 writeb(0, i2c_imx->base + IMX_I2C_I2SR); 219 writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR); 220 221 /* Wait controller to be stable */ 222 udelay(50); 223 224 /* Start I2C transaction */ 225 temp = readb(i2c_imx->base + IMX_I2C_I2CR); 226 temp |= I2CR_MSTA; 227 writeb(temp, i2c_imx->base + IMX_I2C_I2CR); 228 result = i2c_imx_bus_busy(i2c_imx, 1); 229 if (result) 230 return result; 231 i2c_imx->stopped = 0; 232 233 temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK; 234 writeb(temp, i2c_imx->base + IMX_I2C_I2CR); 235 return result; 236 } 237 238 static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx) 239 { 240 unsigned int temp = 0; 241 242 if (!i2c_imx->stopped) { 243 /* Stop I2C transaction */ 244 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 245 temp = readb(i2c_imx->base + IMX_I2C_I2CR); 246 temp &= ~(I2CR_MSTA | I2CR_MTX); 247 writeb(temp, i2c_imx->base + IMX_I2C_I2CR); 248 } 249 if (is_imx1_i2c(i2c_imx)) { 250 /* 251 * This delay caused by an i.MXL hardware bug. 252 * If no (or too short) delay, no "STOP" bit will be generated. 253 */ 254 udelay(i2c_imx->disable_delay); 255 } 256 257 if (!i2c_imx->stopped) { 258 i2c_imx_bus_busy(i2c_imx, 0); 259 i2c_imx->stopped = 1; 260 } 261 262 /* Disable I2C controller */ 263 writeb(0, i2c_imx->base + IMX_I2C_I2CR); 264 clk_disable_unprepare(i2c_imx->clk); 265 } 266 267 static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx, 268 unsigned int rate) 269 { 270 unsigned int i2c_clk_rate; 271 unsigned int div; 272 int i; 273 274 /* Divider value calculation */ 275 i2c_clk_rate = clk_get_rate(i2c_imx->clk); 276 div = (i2c_clk_rate + rate - 1) / rate; 277 if (div < i2c_clk_div[0][0]) 278 i = 0; 279 else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0]) 280 i = ARRAY_SIZE(i2c_clk_div) - 1; 281 else 282 for (i = 0; i2c_clk_div[i][0] < div; i++); 283 284 /* Store divider value */ 285 i2c_imx->ifdr = i2c_clk_div[i][1]; 286 287 /* 288 * There dummy delay is calculated. 289 * It should be about one I2C clock period long. 290 * This delay is used in I2C bus disable function 291 * to fix chip hardware bug. 292 */ 293 i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0] 294 + (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2); 295 296 /* dev_dbg() can't be used, because adapter is not yet registered */ 297 #ifdef CONFIG_I2C_DEBUG_BUS 298 dev_dbg(&i2c_imx->adapter.dev, "<%s> I2C_CLK=%d, REQ DIV=%d\n", 299 __func__, i2c_clk_rate, div); 300 dev_dbg(&i2c_imx->adapter.dev, "<%s> IFDR[IC]=0x%x, REAL DIV=%d\n", 301 __func__, i2c_clk_div[i][1], i2c_clk_div[i][0]); 302 #endif 303 } 304 305 static irqreturn_t i2c_imx_isr(int irq, void *dev_id) 306 { 307 struct imx_i2c_struct *i2c_imx = dev_id; 308 unsigned int temp; 309 310 temp = readb(i2c_imx->base + IMX_I2C_I2SR); 311 if (temp & I2SR_IIF) { 312 /* save status register */ 313 i2c_imx->i2csr = temp; 314 temp &= ~I2SR_IIF; 315 writeb(temp, i2c_imx->base + IMX_I2C_I2SR); 316 wake_up(&i2c_imx->queue); 317 return IRQ_HANDLED; 318 } 319 320 return IRQ_NONE; 321 } 322 323 static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs) 324 { 325 int i, result; 326 327 dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n", 328 __func__, msgs->addr << 1); 329 330 /* write slave address */ 331 writeb(msgs->addr << 1, i2c_imx->base + IMX_I2C_I2DR); 332 result = i2c_imx_trx_complete(i2c_imx); 333 if (result) 334 return result; 335 result = i2c_imx_acked(i2c_imx); 336 if (result) 337 return result; 338 dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__); 339 340 /* write data */ 341 for (i = 0; i < msgs->len; i++) { 342 dev_dbg(&i2c_imx->adapter.dev, 343 "<%s> write byte: B%d=0x%X\n", 344 __func__, i, msgs->buf[i]); 345 writeb(msgs->buf[i], i2c_imx->base + IMX_I2C_I2DR); 346 result = i2c_imx_trx_complete(i2c_imx); 347 if (result) 348 return result; 349 result = i2c_imx_acked(i2c_imx); 350 if (result) 351 return result; 352 } 353 return 0; 354 } 355 356 static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs) 357 { 358 int i, result; 359 unsigned int temp; 360 361 dev_dbg(&i2c_imx->adapter.dev, 362 "<%s> write slave address: addr=0x%x\n", 363 __func__, (msgs->addr << 1) | 0x01); 364 365 /* write slave address */ 366 writeb((msgs->addr << 1) | 0x01, i2c_imx->base + IMX_I2C_I2DR); 367 result = i2c_imx_trx_complete(i2c_imx); 368 if (result) 369 return result; 370 result = i2c_imx_acked(i2c_imx); 371 if (result) 372 return result; 373 374 dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__); 375 376 /* setup bus to read data */ 377 temp = readb(i2c_imx->base + IMX_I2C_I2CR); 378 temp &= ~I2CR_MTX; 379 if (msgs->len - 1) 380 temp &= ~I2CR_TXAK; 381 writeb(temp, i2c_imx->base + IMX_I2C_I2CR); 382 readb(i2c_imx->base + IMX_I2C_I2DR); /* dummy read */ 383 384 dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__); 385 386 /* read data */ 387 for (i = 0; i < msgs->len; i++) { 388 result = i2c_imx_trx_complete(i2c_imx); 389 if (result) 390 return result; 391 if (i == (msgs->len - 1)) { 392 /* It must generate STOP before read I2DR to prevent 393 controller from generating another clock cycle */ 394 dev_dbg(&i2c_imx->adapter.dev, 395 "<%s> clear MSTA\n", __func__); 396 temp = readb(i2c_imx->base + IMX_I2C_I2CR); 397 temp &= ~(I2CR_MSTA | I2CR_MTX); 398 writeb(temp, i2c_imx->base + IMX_I2C_I2CR); 399 i2c_imx_bus_busy(i2c_imx, 0); 400 i2c_imx->stopped = 1; 401 } else if (i == (msgs->len - 2)) { 402 dev_dbg(&i2c_imx->adapter.dev, 403 "<%s> set TXAK\n", __func__); 404 temp = readb(i2c_imx->base + IMX_I2C_I2CR); 405 temp |= I2CR_TXAK; 406 writeb(temp, i2c_imx->base + IMX_I2C_I2CR); 407 } 408 msgs->buf[i] = readb(i2c_imx->base + IMX_I2C_I2DR); 409 dev_dbg(&i2c_imx->adapter.dev, 410 "<%s> read byte: B%d=0x%X\n", 411 __func__, i, msgs->buf[i]); 412 } 413 return 0; 414 } 415 416 static int i2c_imx_xfer(struct i2c_adapter *adapter, 417 struct i2c_msg *msgs, int num) 418 { 419 unsigned int i, temp; 420 int result; 421 struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter); 422 423 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 424 425 /* Start I2C transfer */ 426 result = i2c_imx_start(i2c_imx); 427 if (result) 428 goto fail0; 429 430 /* read/write data */ 431 for (i = 0; i < num; i++) { 432 if (i) { 433 dev_dbg(&i2c_imx->adapter.dev, 434 "<%s> repeated start\n", __func__); 435 temp = readb(i2c_imx->base + IMX_I2C_I2CR); 436 temp |= I2CR_RSTA; 437 writeb(temp, i2c_imx->base + IMX_I2C_I2CR); 438 result = i2c_imx_bus_busy(i2c_imx, 1); 439 if (result) 440 goto fail0; 441 } 442 dev_dbg(&i2c_imx->adapter.dev, 443 "<%s> transfer message: %d\n", __func__, i); 444 /* write/read data */ 445 #ifdef CONFIG_I2C_DEBUG_BUS 446 temp = readb(i2c_imx->base + IMX_I2C_I2CR); 447 dev_dbg(&i2c_imx->adapter.dev, "<%s> CONTROL: IEN=%d, IIEN=%d, " 448 "MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n", __func__, 449 (temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0), 450 (temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0), 451 (temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0)); 452 temp = readb(i2c_imx->base + IMX_I2C_I2SR); 453 dev_dbg(&i2c_imx->adapter.dev, 454 "<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, " 455 "IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n", __func__, 456 (temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0), 457 (temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0), 458 (temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0), 459 (temp & I2SR_RXAK ? 1 : 0)); 460 #endif 461 if (msgs[i].flags & I2C_M_RD) 462 result = i2c_imx_read(i2c_imx, &msgs[i]); 463 else 464 result = i2c_imx_write(i2c_imx, &msgs[i]); 465 if (result) 466 goto fail0; 467 } 468 469 fail0: 470 /* Stop I2C transfer */ 471 i2c_imx_stop(i2c_imx); 472 473 dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__, 474 (result < 0) ? "error" : "success msg", 475 (result < 0) ? result : num); 476 return (result < 0) ? result : num; 477 } 478 479 static u32 i2c_imx_func(struct i2c_adapter *adapter) 480 { 481 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; 482 } 483 484 static struct i2c_algorithm i2c_imx_algo = { 485 .master_xfer = i2c_imx_xfer, 486 .functionality = i2c_imx_func, 487 }; 488 489 static int __init i2c_imx_probe(struct platform_device *pdev) 490 { 491 const struct of_device_id *of_id = of_match_device(i2c_imx_dt_ids, 492 &pdev->dev); 493 struct imx_i2c_struct *i2c_imx; 494 struct resource *res; 495 struct imxi2c_platform_data *pdata = pdev->dev.platform_data; 496 void __iomem *base; 497 int irq, ret; 498 u32 bitrate; 499 500 dev_dbg(&pdev->dev, "<%s>\n", __func__); 501 502 irq = platform_get_irq(pdev, 0); 503 if (irq < 0) { 504 dev_err(&pdev->dev, "can't get irq number\n"); 505 return -ENOENT; 506 } 507 508 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 509 base = devm_ioremap_resource(&pdev->dev, res); 510 if (IS_ERR(base)) 511 return PTR_ERR(base); 512 513 i2c_imx = devm_kzalloc(&pdev->dev, sizeof(struct imx_i2c_struct), 514 GFP_KERNEL); 515 if (!i2c_imx) { 516 dev_err(&pdev->dev, "can't allocate interface\n"); 517 return -ENOMEM; 518 } 519 520 if (of_id) 521 pdev->id_entry = of_id->data; 522 i2c_imx->devtype = pdev->id_entry->driver_data; 523 524 /* Setup i2c_imx driver structure */ 525 strlcpy(i2c_imx->adapter.name, pdev->name, sizeof(i2c_imx->adapter.name)); 526 i2c_imx->adapter.owner = THIS_MODULE; 527 i2c_imx->adapter.algo = &i2c_imx_algo; 528 i2c_imx->adapter.dev.parent = &pdev->dev; 529 i2c_imx->adapter.nr = pdev->id; 530 i2c_imx->adapter.dev.of_node = pdev->dev.of_node; 531 i2c_imx->base = base; 532 533 /* Get I2C clock */ 534 i2c_imx->clk = devm_clk_get(&pdev->dev, NULL); 535 if (IS_ERR(i2c_imx->clk)) { 536 dev_err(&pdev->dev, "can't get I2C clock\n"); 537 return PTR_ERR(i2c_imx->clk); 538 } 539 540 /* Request IRQ */ 541 ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0, 542 pdev->name, i2c_imx); 543 if (ret) { 544 dev_err(&pdev->dev, "can't claim irq %d\n", irq); 545 return ret; 546 } 547 548 /* Init queue */ 549 init_waitqueue_head(&i2c_imx->queue); 550 551 /* Set up adapter data */ 552 i2c_set_adapdata(&i2c_imx->adapter, i2c_imx); 553 554 /* Set up clock divider */ 555 bitrate = IMX_I2C_BIT_RATE; 556 ret = of_property_read_u32(pdev->dev.of_node, 557 "clock-frequency", &bitrate); 558 if (ret < 0 && pdata && pdata->bitrate) 559 bitrate = pdata->bitrate; 560 i2c_imx_set_clk(i2c_imx, bitrate); 561 562 /* Set up chip registers to defaults */ 563 writeb(0, i2c_imx->base + IMX_I2C_I2CR); 564 writeb(0, i2c_imx->base + IMX_I2C_I2SR); 565 566 /* Add I2C adapter */ 567 ret = i2c_add_numbered_adapter(&i2c_imx->adapter); 568 if (ret < 0) { 569 dev_err(&pdev->dev, "registration failed\n"); 570 return ret; 571 } 572 573 of_i2c_register_devices(&i2c_imx->adapter); 574 575 /* Set up platform driver data */ 576 platform_set_drvdata(pdev, i2c_imx); 577 578 dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq); 579 dev_dbg(&i2c_imx->adapter.dev, "device resources from 0x%x to 0x%x\n", 580 res->start, res->end); 581 dev_dbg(&i2c_imx->adapter.dev, "allocated %d bytes at 0x%x\n", 582 resource_size(res), res->start); 583 dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n", 584 i2c_imx->adapter.name); 585 dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n"); 586 587 return 0; /* Return OK */ 588 } 589 590 static int __exit i2c_imx_remove(struct platform_device *pdev) 591 { 592 struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev); 593 594 /* remove adapter */ 595 dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n"); 596 i2c_del_adapter(&i2c_imx->adapter); 597 598 /* setup chip registers to defaults */ 599 writeb(0, i2c_imx->base + IMX_I2C_IADR); 600 writeb(0, i2c_imx->base + IMX_I2C_IFDR); 601 writeb(0, i2c_imx->base + IMX_I2C_I2CR); 602 writeb(0, i2c_imx->base + IMX_I2C_I2SR); 603 604 return 0; 605 } 606 607 static struct platform_driver i2c_imx_driver = { 608 .remove = __exit_p(i2c_imx_remove), 609 .driver = { 610 .name = DRIVER_NAME, 611 .owner = THIS_MODULE, 612 .of_match_table = i2c_imx_dt_ids, 613 }, 614 .id_table = imx_i2c_devtype, 615 }; 616 617 static int __init i2c_adap_imx_init(void) 618 { 619 return platform_driver_probe(&i2c_imx_driver, i2c_imx_probe); 620 } 621 subsys_initcall(i2c_adap_imx_init); 622 623 static void __exit i2c_adap_imx_exit(void) 624 { 625 platform_driver_unregister(&i2c_imx_driver); 626 } 627 module_exit(i2c_adap_imx_exit); 628 629 MODULE_LICENSE("GPL"); 630 MODULE_AUTHOR("Darius Augulis"); 631 MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus"); 632 MODULE_ALIAS("platform:" DRIVER_NAME); 633