1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (C) 2002 Motorola GSG-China 4 * 5 * Author: 6 * Darius Augulis, Teltonika Inc. 7 * 8 * Desc.: 9 * Implementation of I2C Adapter/Algorithm Driver 10 * for I2C Bus integrated in Freescale i.MX/MXC processors 11 * 12 * Derived from Motorola GSG China I2C example driver 13 * 14 * Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de 15 * Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de 16 * Copyright (C) 2007 RightHand Technologies, Inc. 17 * Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt> 18 * 19 * Copyright 2013 Freescale Semiconductor, Inc. 20 * 21 */ 22 23 #include <linux/clk.h> 24 #include <linux/completion.h> 25 #include <linux/delay.h> 26 #include <linux/dma-mapping.h> 27 #include <linux/dmaengine.h> 28 #include <linux/dmapool.h> 29 #include <linux/err.h> 30 #include <linux/errno.h> 31 #include <linux/gpio/consumer.h> 32 #include <linux/i2c.h> 33 #include <linux/init.h> 34 #include <linux/interrupt.h> 35 #include <linux/io.h> 36 #include <linux/kernel.h> 37 #include <linux/module.h> 38 #include <linux/of.h> 39 #include <linux/of_device.h> 40 #include <linux/of_dma.h> 41 #include <linux/pinctrl/consumer.h> 42 #include <linux/platform_data/i2c-imx.h> 43 #include <linux/platform_device.h> 44 #include <linux/pm_runtime.h> 45 #include <linux/sched.h> 46 #include <linux/slab.h> 47 48 /* This will be the driver name the kernel reports */ 49 #define DRIVER_NAME "imx-i2c" 50 51 /* Default value */ 52 #define IMX_I2C_BIT_RATE 100000 /* 100kHz */ 53 54 /* 55 * Enable DMA if transfer byte size is bigger than this threshold. 56 * As the hardware request, it must bigger than 4 bytes.\ 57 * I have set '16' here, maybe it's not the best but I think it's 58 * the appropriate. 59 */ 60 #define DMA_THRESHOLD 16 61 #define DMA_TIMEOUT 1000 62 63 /* IMX I2C registers: 64 * the I2C register offset is different between SoCs, 65 * to provid support for all these chips, split the 66 * register offset into a fixed base address and a 67 * variable shift value, then the full register offset 68 * will be calculated by 69 * reg_off = ( reg_base_addr << reg_shift) 70 */ 71 #define IMX_I2C_IADR 0x00 /* i2c slave address */ 72 #define IMX_I2C_IFDR 0x01 /* i2c frequency divider */ 73 #define IMX_I2C_I2CR 0x02 /* i2c control */ 74 #define IMX_I2C_I2SR 0x03 /* i2c status */ 75 #define IMX_I2C_I2DR 0x04 /* i2c transfer data */ 76 77 #define IMX_I2C_REGSHIFT 2 78 #define VF610_I2C_REGSHIFT 0 79 80 /* Bits of IMX I2C registers */ 81 #define I2SR_RXAK 0x01 82 #define I2SR_IIF 0x02 83 #define I2SR_SRW 0x04 84 #define I2SR_IAL 0x10 85 #define I2SR_IBB 0x20 86 #define I2SR_IAAS 0x40 87 #define I2SR_ICF 0x80 88 #define I2CR_DMAEN 0x02 89 #define I2CR_RSTA 0x04 90 #define I2CR_TXAK 0x08 91 #define I2CR_MTX 0x10 92 #define I2CR_MSTA 0x20 93 #define I2CR_IIEN 0x40 94 #define I2CR_IEN 0x80 95 96 /* register bits different operating codes definition: 97 * 1) I2SR: Interrupt flags clear operation differ between SoCs: 98 * - write zero to clear(w0c) INT flag on i.MX, 99 * - but write one to clear(w1c) INT flag on Vybrid. 100 * 2) I2CR: I2C module enable operation also differ between SoCs: 101 * - set I2CR_IEN bit enable the module on i.MX, 102 * - but clear I2CR_IEN bit enable the module on Vybrid. 103 */ 104 #define I2SR_CLR_OPCODE_W0C 0x0 105 #define I2SR_CLR_OPCODE_W1C (I2SR_IAL | I2SR_IIF) 106 #define I2CR_IEN_OPCODE_0 0x0 107 #define I2CR_IEN_OPCODE_1 I2CR_IEN 108 109 #define I2C_PM_TIMEOUT 10 /* ms */ 110 111 /* 112 * sorted list of clock divider, register value pairs 113 * taken from table 26-5, p.26-9, Freescale i.MX 114 * Integrated Portable System Processor Reference Manual 115 * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007 116 * 117 * Duplicated divider values removed from list 118 */ 119 struct imx_i2c_clk_pair { 120 u16 div; 121 u16 val; 122 }; 123 124 static struct imx_i2c_clk_pair imx_i2c_clk_div[] = { 125 { 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 }, 126 { 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 }, 127 { 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 }, 128 { 56, 0x29 }, { 60, 0x06 }, { 64, 0x2A }, { 72, 0x2B }, 129 { 80, 0x2C }, { 88, 0x09 }, { 96, 0x2D }, { 104, 0x0A }, 130 { 112, 0x2E }, { 128, 0x2F }, { 144, 0x0C }, { 160, 0x30 }, 131 { 192, 0x31 }, { 224, 0x32 }, { 240, 0x0F }, { 256, 0x33 }, 132 { 288, 0x10 }, { 320, 0x34 }, { 384, 0x35 }, { 448, 0x36 }, 133 { 480, 0x13 }, { 512, 0x37 }, { 576, 0x14 }, { 640, 0x38 }, 134 { 768, 0x39 }, { 896, 0x3A }, { 960, 0x17 }, { 1024, 0x3B }, 135 { 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E }, 136 { 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D }, 137 { 3072, 0x1E }, { 3840, 0x1F } 138 }; 139 140 /* Vybrid VF610 clock divider, register value pairs */ 141 static struct imx_i2c_clk_pair vf610_i2c_clk_div[] = { 142 { 20, 0x00 }, { 22, 0x01 }, { 24, 0x02 }, { 26, 0x03 }, 143 { 28, 0x04 }, { 30, 0x05 }, { 32, 0x09 }, { 34, 0x06 }, 144 { 36, 0x0A }, { 40, 0x07 }, { 44, 0x0C }, { 48, 0x0D }, 145 { 52, 0x43 }, { 56, 0x0E }, { 60, 0x45 }, { 64, 0x12 }, 146 { 68, 0x0F }, { 72, 0x13 }, { 80, 0x14 }, { 88, 0x15 }, 147 { 96, 0x19 }, { 104, 0x16 }, { 112, 0x1A }, { 128, 0x17 }, 148 { 136, 0x4F }, { 144, 0x1C }, { 160, 0x1D }, { 176, 0x55 }, 149 { 192, 0x1E }, { 208, 0x56 }, { 224, 0x22 }, { 228, 0x24 }, 150 { 240, 0x1F }, { 256, 0x23 }, { 288, 0x5C }, { 320, 0x25 }, 151 { 384, 0x26 }, { 448, 0x2A }, { 480, 0x27 }, { 512, 0x2B }, 152 { 576, 0x2C }, { 640, 0x2D }, { 768, 0x31 }, { 896, 0x32 }, 153 { 960, 0x2F }, { 1024, 0x33 }, { 1152, 0x34 }, { 1280, 0x35 }, 154 { 1536, 0x36 }, { 1792, 0x3A }, { 1920, 0x37 }, { 2048, 0x3B }, 155 { 2304, 0x3C }, { 2560, 0x3D }, { 3072, 0x3E }, { 3584, 0x7A }, 156 { 3840, 0x3F }, { 4096, 0x7B }, { 5120, 0x7D }, { 6144, 0x7E }, 157 }; 158 159 enum imx_i2c_type { 160 IMX1_I2C, 161 IMX21_I2C, 162 VF610_I2C, 163 }; 164 165 struct imx_i2c_hwdata { 166 enum imx_i2c_type devtype; 167 unsigned regshift; 168 struct imx_i2c_clk_pair *clk_div; 169 unsigned ndivs; 170 unsigned i2sr_clr_opcode; 171 unsigned i2cr_ien_opcode; 172 }; 173 174 struct imx_i2c_dma { 175 struct dma_chan *chan_tx; 176 struct dma_chan *chan_rx; 177 struct dma_chan *chan_using; 178 struct completion cmd_complete; 179 dma_addr_t dma_buf; 180 unsigned int dma_len; 181 enum dma_transfer_direction dma_transfer_dir; 182 enum dma_data_direction dma_data_dir; 183 }; 184 185 struct imx_i2c_struct { 186 struct i2c_adapter adapter; 187 struct clk *clk; 188 struct notifier_block clk_change_nb; 189 void __iomem *base; 190 wait_queue_head_t queue; 191 unsigned long i2csr; 192 unsigned int disable_delay; 193 int stopped; 194 unsigned int ifdr; /* IMX_I2C_IFDR */ 195 unsigned int cur_clk; 196 unsigned int bitrate; 197 const struct imx_i2c_hwdata *hwdata; 198 struct i2c_bus_recovery_info rinfo; 199 200 struct pinctrl *pinctrl; 201 struct pinctrl_state *pinctrl_pins_default; 202 struct pinctrl_state *pinctrl_pins_gpio; 203 204 struct imx_i2c_dma *dma; 205 }; 206 207 static const struct imx_i2c_hwdata imx1_i2c_hwdata = { 208 .devtype = IMX1_I2C, 209 .regshift = IMX_I2C_REGSHIFT, 210 .clk_div = imx_i2c_clk_div, 211 .ndivs = ARRAY_SIZE(imx_i2c_clk_div), 212 .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C, 213 .i2cr_ien_opcode = I2CR_IEN_OPCODE_1, 214 215 }; 216 217 static const struct imx_i2c_hwdata imx21_i2c_hwdata = { 218 .devtype = IMX21_I2C, 219 .regshift = IMX_I2C_REGSHIFT, 220 .clk_div = imx_i2c_clk_div, 221 .ndivs = ARRAY_SIZE(imx_i2c_clk_div), 222 .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C, 223 .i2cr_ien_opcode = I2CR_IEN_OPCODE_1, 224 225 }; 226 227 static struct imx_i2c_hwdata vf610_i2c_hwdata = { 228 .devtype = VF610_I2C, 229 .regshift = VF610_I2C_REGSHIFT, 230 .clk_div = vf610_i2c_clk_div, 231 .ndivs = ARRAY_SIZE(vf610_i2c_clk_div), 232 .i2sr_clr_opcode = I2SR_CLR_OPCODE_W1C, 233 .i2cr_ien_opcode = I2CR_IEN_OPCODE_0, 234 235 }; 236 237 static const struct platform_device_id imx_i2c_devtype[] = { 238 { 239 .name = "imx1-i2c", 240 .driver_data = (kernel_ulong_t)&imx1_i2c_hwdata, 241 }, { 242 .name = "imx21-i2c", 243 .driver_data = (kernel_ulong_t)&imx21_i2c_hwdata, 244 }, { 245 /* sentinel */ 246 } 247 }; 248 MODULE_DEVICE_TABLE(platform, imx_i2c_devtype); 249 250 static const struct of_device_id i2c_imx_dt_ids[] = { 251 { .compatible = "fsl,imx1-i2c", .data = &imx1_i2c_hwdata, }, 252 { .compatible = "fsl,imx21-i2c", .data = &imx21_i2c_hwdata, }, 253 { .compatible = "fsl,vf610-i2c", .data = &vf610_i2c_hwdata, }, 254 { /* sentinel */ } 255 }; 256 MODULE_DEVICE_TABLE(of, i2c_imx_dt_ids); 257 258 static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx) 259 { 260 return i2c_imx->hwdata->devtype == IMX1_I2C; 261 } 262 263 static inline void imx_i2c_write_reg(unsigned int val, 264 struct imx_i2c_struct *i2c_imx, unsigned int reg) 265 { 266 writeb(val, i2c_imx->base + (reg << i2c_imx->hwdata->regshift)); 267 } 268 269 static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx, 270 unsigned int reg) 271 { 272 return readb(i2c_imx->base + (reg << i2c_imx->hwdata->regshift)); 273 } 274 275 /* Functions for DMA support */ 276 static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx, 277 dma_addr_t phy_addr) 278 { 279 struct imx_i2c_dma *dma; 280 struct dma_slave_config dma_sconfig; 281 struct device *dev = &i2c_imx->adapter.dev; 282 int ret; 283 284 dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL); 285 if (!dma) 286 return; 287 288 dma->chan_tx = dma_request_slave_channel(dev, "tx"); 289 if (!dma->chan_tx) { 290 dev_dbg(dev, "can't request DMA tx channel\n"); 291 goto fail_al; 292 } 293 294 dma_sconfig.dst_addr = phy_addr + 295 (IMX_I2C_I2DR << i2c_imx->hwdata->regshift); 296 dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; 297 dma_sconfig.dst_maxburst = 1; 298 dma_sconfig.direction = DMA_MEM_TO_DEV; 299 ret = dmaengine_slave_config(dma->chan_tx, &dma_sconfig); 300 if (ret < 0) { 301 dev_dbg(dev, "can't configure tx channel\n"); 302 goto fail_tx; 303 } 304 305 dma->chan_rx = dma_request_slave_channel(dev, "rx"); 306 if (!dma->chan_rx) { 307 dev_dbg(dev, "can't request DMA rx channel\n"); 308 goto fail_tx; 309 } 310 311 dma_sconfig.src_addr = phy_addr + 312 (IMX_I2C_I2DR << i2c_imx->hwdata->regshift); 313 dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; 314 dma_sconfig.src_maxburst = 1; 315 dma_sconfig.direction = DMA_DEV_TO_MEM; 316 ret = dmaengine_slave_config(dma->chan_rx, &dma_sconfig); 317 if (ret < 0) { 318 dev_dbg(dev, "can't configure rx channel\n"); 319 goto fail_rx; 320 } 321 322 i2c_imx->dma = dma; 323 init_completion(&dma->cmd_complete); 324 dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n", 325 dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx)); 326 327 return; 328 329 fail_rx: 330 dma_release_channel(dma->chan_rx); 331 fail_tx: 332 dma_release_channel(dma->chan_tx); 333 fail_al: 334 devm_kfree(dev, dma); 335 dev_info(dev, "can't use DMA, using PIO instead.\n"); 336 } 337 338 static void i2c_imx_dma_callback(void *arg) 339 { 340 struct imx_i2c_struct *i2c_imx = (struct imx_i2c_struct *)arg; 341 struct imx_i2c_dma *dma = i2c_imx->dma; 342 343 dma_unmap_single(dma->chan_using->device->dev, dma->dma_buf, 344 dma->dma_len, dma->dma_data_dir); 345 complete(&dma->cmd_complete); 346 } 347 348 static int i2c_imx_dma_xfer(struct imx_i2c_struct *i2c_imx, 349 struct i2c_msg *msgs) 350 { 351 struct imx_i2c_dma *dma = i2c_imx->dma; 352 struct dma_async_tx_descriptor *txdesc; 353 struct device *dev = &i2c_imx->adapter.dev; 354 struct device *chan_dev = dma->chan_using->device->dev; 355 356 dma->dma_buf = dma_map_single(chan_dev, msgs->buf, 357 dma->dma_len, dma->dma_data_dir); 358 if (dma_mapping_error(chan_dev, dma->dma_buf)) { 359 dev_err(dev, "DMA mapping failed\n"); 360 goto err_map; 361 } 362 363 txdesc = dmaengine_prep_slave_single(dma->chan_using, dma->dma_buf, 364 dma->dma_len, dma->dma_transfer_dir, 365 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 366 if (!txdesc) { 367 dev_err(dev, "Not able to get desc for DMA xfer\n"); 368 goto err_desc; 369 } 370 371 reinit_completion(&dma->cmd_complete); 372 txdesc->callback = i2c_imx_dma_callback; 373 txdesc->callback_param = i2c_imx; 374 if (dma_submit_error(dmaengine_submit(txdesc))) { 375 dev_err(dev, "DMA submit failed\n"); 376 goto err_submit; 377 } 378 379 dma_async_issue_pending(dma->chan_using); 380 return 0; 381 382 err_submit: 383 dmaengine_terminate_all(dma->chan_using); 384 err_desc: 385 dma_unmap_single(chan_dev, dma->dma_buf, 386 dma->dma_len, dma->dma_data_dir); 387 err_map: 388 return -EINVAL; 389 } 390 391 static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx) 392 { 393 struct imx_i2c_dma *dma = i2c_imx->dma; 394 395 dma->dma_buf = 0; 396 dma->dma_len = 0; 397 398 dma_release_channel(dma->chan_tx); 399 dma->chan_tx = NULL; 400 401 dma_release_channel(dma->chan_rx); 402 dma->chan_rx = NULL; 403 404 dma->chan_using = NULL; 405 } 406 407 static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy) 408 { 409 unsigned long orig_jiffies = jiffies; 410 unsigned int temp; 411 412 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 413 414 while (1) { 415 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); 416 417 /* check for arbitration lost */ 418 if (temp & I2SR_IAL) { 419 temp &= ~I2SR_IAL; 420 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); 421 return -EAGAIN; 422 } 423 424 if (for_busy && (temp & I2SR_IBB)) 425 break; 426 if (!for_busy && !(temp & I2SR_IBB)) 427 break; 428 if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) { 429 dev_dbg(&i2c_imx->adapter.dev, 430 "<%s> I2C bus is busy\n", __func__); 431 return -ETIMEDOUT; 432 } 433 schedule(); 434 } 435 436 return 0; 437 } 438 439 static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx) 440 { 441 wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10); 442 443 if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) { 444 dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__); 445 return -ETIMEDOUT; 446 } 447 dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__); 448 i2c_imx->i2csr = 0; 449 return 0; 450 } 451 452 static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx) 453 { 454 if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) { 455 dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__); 456 return -ENXIO; /* No ACK */ 457 } 458 459 dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__); 460 return 0; 461 } 462 463 static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx, 464 unsigned int i2c_clk_rate) 465 { 466 struct imx_i2c_clk_pair *i2c_clk_div = i2c_imx->hwdata->clk_div; 467 unsigned int div; 468 int i; 469 470 /* Divider value calculation */ 471 if (i2c_imx->cur_clk == i2c_clk_rate) 472 return; 473 474 i2c_imx->cur_clk = i2c_clk_rate; 475 476 div = (i2c_clk_rate + i2c_imx->bitrate - 1) / i2c_imx->bitrate; 477 if (div < i2c_clk_div[0].div) 478 i = 0; 479 else if (div > i2c_clk_div[i2c_imx->hwdata->ndivs - 1].div) 480 i = i2c_imx->hwdata->ndivs - 1; 481 else 482 for (i = 0; i2c_clk_div[i].div < div; i++) 483 ; 484 485 /* Store divider value */ 486 i2c_imx->ifdr = i2c_clk_div[i].val; 487 488 /* 489 * There dummy delay is calculated. 490 * It should be about one I2C clock period long. 491 * This delay is used in I2C bus disable function 492 * to fix chip hardware bug. 493 */ 494 i2c_imx->disable_delay = (500000U * i2c_clk_div[i].div 495 + (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2); 496 497 #ifdef CONFIG_I2C_DEBUG_BUS 498 dev_dbg(&i2c_imx->adapter.dev, "I2C_CLK=%d, REQ DIV=%d\n", 499 i2c_clk_rate, div); 500 dev_dbg(&i2c_imx->adapter.dev, "IFDR[IC]=0x%x, REAL DIV=%d\n", 501 i2c_clk_div[i].val, i2c_clk_div[i].div); 502 #endif 503 } 504 505 static int i2c_imx_clk_notifier_call(struct notifier_block *nb, 506 unsigned long action, void *data) 507 { 508 struct clk_notifier_data *ndata = data; 509 struct imx_i2c_struct *i2c_imx = container_of(&ndata->clk, 510 struct imx_i2c_struct, 511 clk); 512 513 if (action & POST_RATE_CHANGE) 514 i2c_imx_set_clk(i2c_imx, ndata->new_rate); 515 516 return NOTIFY_OK; 517 } 518 519 static int i2c_imx_start(struct imx_i2c_struct *i2c_imx) 520 { 521 unsigned int temp = 0; 522 int result; 523 524 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 525 526 imx_i2c_write_reg(i2c_imx->ifdr, i2c_imx, IMX_I2C_IFDR); 527 /* Enable I2C controller */ 528 imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR); 529 imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode, i2c_imx, IMX_I2C_I2CR); 530 531 /* Wait controller to be stable */ 532 usleep_range(50, 150); 533 534 /* Start I2C transaction */ 535 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 536 temp |= I2CR_MSTA; 537 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 538 result = i2c_imx_bus_busy(i2c_imx, 1); 539 if (result) 540 return result; 541 i2c_imx->stopped = 0; 542 543 temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK; 544 temp &= ~I2CR_DMAEN; 545 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 546 return result; 547 } 548 549 static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx) 550 { 551 unsigned int temp = 0; 552 553 if (!i2c_imx->stopped) { 554 /* Stop I2C transaction */ 555 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 556 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 557 temp &= ~(I2CR_MSTA | I2CR_MTX); 558 if (i2c_imx->dma) 559 temp &= ~I2CR_DMAEN; 560 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 561 } 562 if (is_imx1_i2c(i2c_imx)) { 563 /* 564 * This delay caused by an i.MXL hardware bug. 565 * If no (or too short) delay, no "STOP" bit will be generated. 566 */ 567 udelay(i2c_imx->disable_delay); 568 } 569 570 if (!i2c_imx->stopped) { 571 i2c_imx_bus_busy(i2c_imx, 0); 572 i2c_imx->stopped = 1; 573 } 574 575 /* Disable I2C controller */ 576 temp = i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN, 577 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 578 } 579 580 static irqreturn_t i2c_imx_isr(int irq, void *dev_id) 581 { 582 struct imx_i2c_struct *i2c_imx = dev_id; 583 unsigned int temp; 584 585 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); 586 if (temp & I2SR_IIF) { 587 /* save status register */ 588 i2c_imx->i2csr = temp; 589 temp &= ~I2SR_IIF; 590 temp |= (i2c_imx->hwdata->i2sr_clr_opcode & I2SR_IIF); 591 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); 592 wake_up(&i2c_imx->queue); 593 return IRQ_HANDLED; 594 } 595 596 return IRQ_NONE; 597 } 598 599 static int i2c_imx_dma_write(struct imx_i2c_struct *i2c_imx, 600 struct i2c_msg *msgs) 601 { 602 int result; 603 unsigned long time_left; 604 unsigned int temp = 0; 605 unsigned long orig_jiffies = jiffies; 606 struct imx_i2c_dma *dma = i2c_imx->dma; 607 struct device *dev = &i2c_imx->adapter.dev; 608 609 dma->chan_using = dma->chan_tx; 610 dma->dma_transfer_dir = DMA_MEM_TO_DEV; 611 dma->dma_data_dir = DMA_TO_DEVICE; 612 dma->dma_len = msgs->len - 1; 613 result = i2c_imx_dma_xfer(i2c_imx, msgs); 614 if (result) 615 return result; 616 617 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 618 temp |= I2CR_DMAEN; 619 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 620 621 /* 622 * Write slave address. 623 * The first byte must be transmitted by the CPU. 624 */ 625 imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR); 626 time_left = wait_for_completion_timeout( 627 &i2c_imx->dma->cmd_complete, 628 msecs_to_jiffies(DMA_TIMEOUT)); 629 if (time_left == 0) { 630 dmaengine_terminate_all(dma->chan_using); 631 return -ETIMEDOUT; 632 } 633 634 /* Waiting for transfer complete. */ 635 while (1) { 636 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); 637 if (temp & I2SR_ICF) 638 break; 639 if (time_after(jiffies, orig_jiffies + 640 msecs_to_jiffies(DMA_TIMEOUT))) { 641 dev_dbg(dev, "<%s> Timeout\n", __func__); 642 return -ETIMEDOUT; 643 } 644 schedule(); 645 } 646 647 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 648 temp &= ~I2CR_DMAEN; 649 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 650 651 /* The last data byte must be transferred by the CPU. */ 652 imx_i2c_write_reg(msgs->buf[msgs->len-1], 653 i2c_imx, IMX_I2C_I2DR); 654 result = i2c_imx_trx_complete(i2c_imx); 655 if (result) 656 return result; 657 658 return i2c_imx_acked(i2c_imx); 659 } 660 661 static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx, 662 struct i2c_msg *msgs, bool is_lastmsg) 663 { 664 int result; 665 unsigned long time_left; 666 unsigned int temp; 667 unsigned long orig_jiffies = jiffies; 668 struct imx_i2c_dma *dma = i2c_imx->dma; 669 struct device *dev = &i2c_imx->adapter.dev; 670 671 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 672 temp |= I2CR_DMAEN; 673 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 674 675 dma->chan_using = dma->chan_rx; 676 dma->dma_transfer_dir = DMA_DEV_TO_MEM; 677 dma->dma_data_dir = DMA_FROM_DEVICE; 678 /* The last two data bytes must be transferred by the CPU. */ 679 dma->dma_len = msgs->len - 2; 680 result = i2c_imx_dma_xfer(i2c_imx, msgs); 681 if (result) 682 return result; 683 684 time_left = wait_for_completion_timeout( 685 &i2c_imx->dma->cmd_complete, 686 msecs_to_jiffies(DMA_TIMEOUT)); 687 if (time_left == 0) { 688 dmaengine_terminate_all(dma->chan_using); 689 return -ETIMEDOUT; 690 } 691 692 /* waiting for transfer complete. */ 693 while (1) { 694 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); 695 if (temp & I2SR_ICF) 696 break; 697 if (time_after(jiffies, orig_jiffies + 698 msecs_to_jiffies(DMA_TIMEOUT))) { 699 dev_dbg(dev, "<%s> Timeout\n", __func__); 700 return -ETIMEDOUT; 701 } 702 schedule(); 703 } 704 705 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 706 temp &= ~I2CR_DMAEN; 707 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 708 709 /* read n-1 byte data */ 710 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 711 temp |= I2CR_TXAK; 712 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 713 714 msgs->buf[msgs->len-2] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); 715 /* read n byte data */ 716 result = i2c_imx_trx_complete(i2c_imx); 717 if (result) 718 return result; 719 720 if (is_lastmsg) { 721 /* 722 * It must generate STOP before read I2DR to prevent 723 * controller from generating another clock cycle 724 */ 725 dev_dbg(dev, "<%s> clear MSTA\n", __func__); 726 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 727 temp &= ~(I2CR_MSTA | I2CR_MTX); 728 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 729 i2c_imx_bus_busy(i2c_imx, 0); 730 i2c_imx->stopped = 1; 731 } else { 732 /* 733 * For i2c master receiver repeat restart operation like: 734 * read -> repeat MSTA -> read/write 735 * The controller must set MTX before read the last byte in 736 * the first read operation, otherwise the first read cost 737 * one extra clock cycle. 738 */ 739 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 740 temp |= I2CR_MTX; 741 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 742 } 743 msgs->buf[msgs->len-1] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); 744 745 return 0; 746 } 747 748 static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs) 749 { 750 int i, result; 751 752 dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n", 753 __func__, i2c_8bit_addr_from_msg(msgs)); 754 755 /* write slave address */ 756 imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR); 757 result = i2c_imx_trx_complete(i2c_imx); 758 if (result) 759 return result; 760 result = i2c_imx_acked(i2c_imx); 761 if (result) 762 return result; 763 dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__); 764 765 /* write data */ 766 for (i = 0; i < msgs->len; i++) { 767 dev_dbg(&i2c_imx->adapter.dev, 768 "<%s> write byte: B%d=0x%X\n", 769 __func__, i, msgs->buf[i]); 770 imx_i2c_write_reg(msgs->buf[i], i2c_imx, IMX_I2C_I2DR); 771 result = i2c_imx_trx_complete(i2c_imx); 772 if (result) 773 return result; 774 result = i2c_imx_acked(i2c_imx); 775 if (result) 776 return result; 777 } 778 return 0; 779 } 780 781 static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, bool is_lastmsg) 782 { 783 int i, result; 784 unsigned int temp; 785 int block_data = msgs->flags & I2C_M_RECV_LEN; 786 787 dev_dbg(&i2c_imx->adapter.dev, 788 "<%s> write slave address: addr=0x%x\n", 789 __func__, i2c_8bit_addr_from_msg(msgs)); 790 791 /* write slave address */ 792 imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR); 793 result = i2c_imx_trx_complete(i2c_imx); 794 if (result) 795 return result; 796 result = i2c_imx_acked(i2c_imx); 797 if (result) 798 return result; 799 800 dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__); 801 802 /* setup bus to read data */ 803 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 804 temp &= ~I2CR_MTX; 805 806 /* 807 * Reset the I2CR_TXAK flag initially for SMBus block read since the 808 * length is unknown 809 */ 810 if ((msgs->len - 1) || block_data) 811 temp &= ~I2CR_TXAK; 812 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 813 imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */ 814 815 dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__); 816 817 if (i2c_imx->dma && msgs->len >= DMA_THRESHOLD && !block_data) 818 return i2c_imx_dma_read(i2c_imx, msgs, is_lastmsg); 819 820 /* read data */ 821 for (i = 0; i < msgs->len; i++) { 822 u8 len = 0; 823 824 result = i2c_imx_trx_complete(i2c_imx); 825 if (result) 826 return result; 827 /* 828 * First byte is the length of remaining packet 829 * in the SMBus block data read. Add it to 830 * msgs->len. 831 */ 832 if ((!i) && block_data) { 833 len = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); 834 if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX)) 835 return -EPROTO; 836 dev_dbg(&i2c_imx->adapter.dev, 837 "<%s> read length: 0x%X\n", 838 __func__, len); 839 msgs->len += len; 840 } 841 if (i == (msgs->len - 1)) { 842 if (is_lastmsg) { 843 /* 844 * It must generate STOP before read I2DR to prevent 845 * controller from generating another clock cycle 846 */ 847 dev_dbg(&i2c_imx->adapter.dev, 848 "<%s> clear MSTA\n", __func__); 849 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 850 temp &= ~(I2CR_MSTA | I2CR_MTX); 851 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 852 i2c_imx_bus_busy(i2c_imx, 0); 853 i2c_imx->stopped = 1; 854 } else { 855 /* 856 * For i2c master receiver repeat restart operation like: 857 * read -> repeat MSTA -> read/write 858 * The controller must set MTX before read the last byte in 859 * the first read operation, otherwise the first read cost 860 * one extra clock cycle. 861 */ 862 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 863 temp |= I2CR_MTX; 864 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 865 } 866 } else if (i == (msgs->len - 2)) { 867 dev_dbg(&i2c_imx->adapter.dev, 868 "<%s> set TXAK\n", __func__); 869 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 870 temp |= I2CR_TXAK; 871 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 872 } 873 if ((!i) && block_data) 874 msgs->buf[0] = len; 875 else 876 msgs->buf[i] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); 877 dev_dbg(&i2c_imx->adapter.dev, 878 "<%s> read byte: B%d=0x%X\n", 879 __func__, i, msgs->buf[i]); 880 } 881 return 0; 882 } 883 884 static int i2c_imx_xfer(struct i2c_adapter *adapter, 885 struct i2c_msg *msgs, int num) 886 { 887 unsigned int i, temp; 888 int result; 889 bool is_lastmsg = false; 890 struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter); 891 892 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 893 894 result = pm_runtime_get_sync(i2c_imx->adapter.dev.parent); 895 if (result < 0) 896 goto out; 897 898 /* Start I2C transfer */ 899 result = i2c_imx_start(i2c_imx); 900 if (result) { 901 if (i2c_imx->adapter.bus_recovery_info) { 902 i2c_recover_bus(&i2c_imx->adapter); 903 result = i2c_imx_start(i2c_imx); 904 } 905 } 906 907 if (result) 908 goto fail0; 909 910 /* read/write data */ 911 for (i = 0; i < num; i++) { 912 if (i == num - 1) 913 is_lastmsg = true; 914 915 if (i) { 916 dev_dbg(&i2c_imx->adapter.dev, 917 "<%s> repeated start\n", __func__); 918 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 919 temp |= I2CR_RSTA; 920 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 921 result = i2c_imx_bus_busy(i2c_imx, 1); 922 if (result) 923 goto fail0; 924 } 925 dev_dbg(&i2c_imx->adapter.dev, 926 "<%s> transfer message: %d\n", __func__, i); 927 /* write/read data */ 928 #ifdef CONFIG_I2C_DEBUG_BUS 929 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 930 dev_dbg(&i2c_imx->adapter.dev, 931 "<%s> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n", 932 __func__, 933 (temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0), 934 (temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0), 935 (temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0)); 936 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); 937 dev_dbg(&i2c_imx->adapter.dev, 938 "<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n", 939 __func__, 940 (temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0), 941 (temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0), 942 (temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0), 943 (temp & I2SR_RXAK ? 1 : 0)); 944 #endif 945 if (msgs[i].flags & I2C_M_RD) 946 result = i2c_imx_read(i2c_imx, &msgs[i], is_lastmsg); 947 else { 948 if (i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD) 949 result = i2c_imx_dma_write(i2c_imx, &msgs[i]); 950 else 951 result = i2c_imx_write(i2c_imx, &msgs[i]); 952 } 953 if (result) 954 goto fail0; 955 } 956 957 fail0: 958 /* Stop I2C transfer */ 959 i2c_imx_stop(i2c_imx); 960 961 pm_runtime_mark_last_busy(i2c_imx->adapter.dev.parent); 962 pm_runtime_put_autosuspend(i2c_imx->adapter.dev.parent); 963 964 out: 965 dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__, 966 (result < 0) ? "error" : "success msg", 967 (result < 0) ? result : num); 968 return (result < 0) ? result : num; 969 } 970 971 static void i2c_imx_prepare_recovery(struct i2c_adapter *adap) 972 { 973 struct imx_i2c_struct *i2c_imx; 974 975 i2c_imx = container_of(adap, struct imx_i2c_struct, adapter); 976 977 pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_gpio); 978 } 979 980 static void i2c_imx_unprepare_recovery(struct i2c_adapter *adap) 981 { 982 struct imx_i2c_struct *i2c_imx; 983 984 i2c_imx = container_of(adap, struct imx_i2c_struct, adapter); 985 986 pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_default); 987 } 988 989 /* 990 * We switch SCL and SDA to their GPIO function and do some bitbanging 991 * for bus recovery. These alternative pinmux settings can be 992 * described in the device tree by a separate pinctrl state "gpio". If 993 * this is missing this is not a big problem, the only implication is 994 * that we can't do bus recovery. 995 */ 996 static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx, 997 struct platform_device *pdev) 998 { 999 struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo; 1000 1001 i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev); 1002 if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) { 1003 dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n"); 1004 return PTR_ERR(i2c_imx->pinctrl); 1005 } 1006 1007 i2c_imx->pinctrl_pins_default = pinctrl_lookup_state(i2c_imx->pinctrl, 1008 PINCTRL_STATE_DEFAULT); 1009 i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl, 1010 "gpio"); 1011 rinfo->sda_gpiod = devm_gpiod_get(&pdev->dev, "sda", GPIOD_IN); 1012 rinfo->scl_gpiod = devm_gpiod_get(&pdev->dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN); 1013 1014 if (PTR_ERR(rinfo->sda_gpiod) == -EPROBE_DEFER || 1015 PTR_ERR(rinfo->scl_gpiod) == -EPROBE_DEFER) { 1016 return -EPROBE_DEFER; 1017 } else if (IS_ERR(rinfo->sda_gpiod) || 1018 IS_ERR(rinfo->scl_gpiod) || 1019 IS_ERR(i2c_imx->pinctrl_pins_default) || 1020 IS_ERR(i2c_imx->pinctrl_pins_gpio)) { 1021 dev_dbg(&pdev->dev, "recovery information incomplete\n"); 1022 return 0; 1023 } 1024 1025 dev_dbg(&pdev->dev, "using scl%s for recovery\n", 1026 rinfo->sda_gpiod ? ",sda" : ""); 1027 1028 rinfo->prepare_recovery = i2c_imx_prepare_recovery; 1029 rinfo->unprepare_recovery = i2c_imx_unprepare_recovery; 1030 rinfo->recover_bus = i2c_generic_scl_recovery; 1031 i2c_imx->adapter.bus_recovery_info = rinfo; 1032 1033 return 0; 1034 } 1035 1036 static u32 i2c_imx_func(struct i2c_adapter *adapter) 1037 { 1038 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL 1039 | I2C_FUNC_SMBUS_READ_BLOCK_DATA; 1040 } 1041 1042 static const struct i2c_algorithm i2c_imx_algo = { 1043 .master_xfer = i2c_imx_xfer, 1044 .functionality = i2c_imx_func, 1045 }; 1046 1047 static int i2c_imx_probe(struct platform_device *pdev) 1048 { 1049 const struct of_device_id *of_id = of_match_device(i2c_imx_dt_ids, 1050 &pdev->dev); 1051 struct imx_i2c_struct *i2c_imx; 1052 struct resource *res; 1053 struct imxi2c_platform_data *pdata = dev_get_platdata(&pdev->dev); 1054 void __iomem *base; 1055 int irq, ret; 1056 dma_addr_t phy_addr; 1057 1058 dev_dbg(&pdev->dev, "<%s>\n", __func__); 1059 1060 irq = platform_get_irq(pdev, 0); 1061 if (irq < 0) { 1062 dev_err(&pdev->dev, "can't get irq number\n"); 1063 return irq; 1064 } 1065 1066 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1067 base = devm_ioremap_resource(&pdev->dev, res); 1068 if (IS_ERR(base)) 1069 return PTR_ERR(base); 1070 1071 phy_addr = (dma_addr_t)res->start; 1072 i2c_imx = devm_kzalloc(&pdev->dev, sizeof(*i2c_imx), GFP_KERNEL); 1073 if (!i2c_imx) 1074 return -ENOMEM; 1075 1076 if (of_id) 1077 i2c_imx->hwdata = of_id->data; 1078 else 1079 i2c_imx->hwdata = (struct imx_i2c_hwdata *) 1080 platform_get_device_id(pdev)->driver_data; 1081 1082 /* Setup i2c_imx driver structure */ 1083 strlcpy(i2c_imx->adapter.name, pdev->name, sizeof(i2c_imx->adapter.name)); 1084 i2c_imx->adapter.owner = THIS_MODULE; 1085 i2c_imx->adapter.algo = &i2c_imx_algo; 1086 i2c_imx->adapter.dev.parent = &pdev->dev; 1087 i2c_imx->adapter.nr = pdev->id; 1088 i2c_imx->adapter.dev.of_node = pdev->dev.of_node; 1089 i2c_imx->base = base; 1090 1091 /* Get I2C clock */ 1092 i2c_imx->clk = devm_clk_get(&pdev->dev, NULL); 1093 if (IS_ERR(i2c_imx->clk)) { 1094 dev_err(&pdev->dev, "can't get I2C clock\n"); 1095 return PTR_ERR(i2c_imx->clk); 1096 } 1097 1098 ret = clk_prepare_enable(i2c_imx->clk); 1099 if (ret) { 1100 dev_err(&pdev->dev, "can't enable I2C clock, ret=%d\n", ret); 1101 return ret; 1102 } 1103 1104 /* Request IRQ */ 1105 ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, IRQF_SHARED, 1106 pdev->name, i2c_imx); 1107 if (ret) { 1108 dev_err(&pdev->dev, "can't claim irq %d\n", irq); 1109 goto clk_disable; 1110 } 1111 1112 /* Init queue */ 1113 init_waitqueue_head(&i2c_imx->queue); 1114 1115 /* Set up adapter data */ 1116 i2c_set_adapdata(&i2c_imx->adapter, i2c_imx); 1117 1118 /* Set up platform driver data */ 1119 platform_set_drvdata(pdev, i2c_imx); 1120 1121 pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT); 1122 pm_runtime_use_autosuspend(&pdev->dev); 1123 pm_runtime_set_active(&pdev->dev); 1124 pm_runtime_enable(&pdev->dev); 1125 1126 ret = pm_runtime_get_sync(&pdev->dev); 1127 if (ret < 0) 1128 goto rpm_disable; 1129 1130 /* Set up clock divider */ 1131 i2c_imx->bitrate = IMX_I2C_BIT_RATE; 1132 ret = of_property_read_u32(pdev->dev.of_node, 1133 "clock-frequency", &i2c_imx->bitrate); 1134 if (ret < 0 && pdata && pdata->bitrate) 1135 i2c_imx->bitrate = pdata->bitrate; 1136 i2c_imx->clk_change_nb.notifier_call = i2c_imx_clk_notifier_call; 1137 clk_notifier_register(i2c_imx->clk, &i2c_imx->clk_change_nb); 1138 i2c_imx_set_clk(i2c_imx, clk_get_rate(i2c_imx->clk)); 1139 1140 /* Set up chip registers to defaults */ 1141 imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN, 1142 i2c_imx, IMX_I2C_I2CR); 1143 imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR); 1144 1145 /* Init optional bus recovery function */ 1146 ret = i2c_imx_init_recovery_info(i2c_imx, pdev); 1147 /* Give it another chance if pinctrl used is not ready yet */ 1148 if (ret == -EPROBE_DEFER) 1149 goto clk_notifier_unregister; 1150 1151 /* Add I2C adapter */ 1152 ret = i2c_add_numbered_adapter(&i2c_imx->adapter); 1153 if (ret < 0) 1154 goto clk_notifier_unregister; 1155 1156 pm_runtime_mark_last_busy(&pdev->dev); 1157 pm_runtime_put_autosuspend(&pdev->dev); 1158 1159 dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq); 1160 dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res); 1161 dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n", 1162 i2c_imx->adapter.name); 1163 dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n"); 1164 1165 /* Init DMA config if supported */ 1166 i2c_imx_dma_request(i2c_imx, phy_addr); 1167 1168 return 0; /* Return OK */ 1169 1170 clk_notifier_unregister: 1171 clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb); 1172 rpm_disable: 1173 pm_runtime_put_noidle(&pdev->dev); 1174 pm_runtime_disable(&pdev->dev); 1175 pm_runtime_set_suspended(&pdev->dev); 1176 pm_runtime_dont_use_autosuspend(&pdev->dev); 1177 1178 clk_disable: 1179 clk_disable_unprepare(i2c_imx->clk); 1180 return ret; 1181 } 1182 1183 static int i2c_imx_remove(struct platform_device *pdev) 1184 { 1185 struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev); 1186 int ret; 1187 1188 ret = pm_runtime_get_sync(&pdev->dev); 1189 if (ret < 0) 1190 return ret; 1191 1192 /* remove adapter */ 1193 dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n"); 1194 i2c_del_adapter(&i2c_imx->adapter); 1195 1196 if (i2c_imx->dma) 1197 i2c_imx_dma_free(i2c_imx); 1198 1199 /* setup chip registers to defaults */ 1200 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR); 1201 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IFDR); 1202 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR); 1203 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR); 1204 1205 clk_notifier_unregister(i2c_imx->clk, &i2c_imx->clk_change_nb); 1206 clk_disable_unprepare(i2c_imx->clk); 1207 1208 pm_runtime_put_noidle(&pdev->dev); 1209 pm_runtime_disable(&pdev->dev); 1210 1211 return 0; 1212 } 1213 1214 #ifdef CONFIG_PM 1215 static int i2c_imx_runtime_suspend(struct device *dev) 1216 { 1217 struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev); 1218 1219 clk_disable(i2c_imx->clk); 1220 1221 return 0; 1222 } 1223 1224 static int i2c_imx_runtime_resume(struct device *dev) 1225 { 1226 struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev); 1227 int ret; 1228 1229 ret = clk_enable(i2c_imx->clk); 1230 if (ret) 1231 dev_err(dev, "can't enable I2C clock, ret=%d\n", ret); 1232 1233 return ret; 1234 } 1235 1236 static const struct dev_pm_ops i2c_imx_pm_ops = { 1237 SET_RUNTIME_PM_OPS(i2c_imx_runtime_suspend, 1238 i2c_imx_runtime_resume, NULL) 1239 }; 1240 #define I2C_IMX_PM_OPS (&i2c_imx_pm_ops) 1241 #else 1242 #define I2C_IMX_PM_OPS NULL 1243 #endif /* CONFIG_PM */ 1244 1245 static struct platform_driver i2c_imx_driver = { 1246 .probe = i2c_imx_probe, 1247 .remove = i2c_imx_remove, 1248 .driver = { 1249 .name = DRIVER_NAME, 1250 .pm = I2C_IMX_PM_OPS, 1251 .of_match_table = i2c_imx_dt_ids, 1252 }, 1253 .id_table = imx_i2c_devtype, 1254 }; 1255 1256 static int __init i2c_adap_imx_init(void) 1257 { 1258 return platform_driver_register(&i2c_imx_driver); 1259 } 1260 subsys_initcall(i2c_adap_imx_init); 1261 1262 static void __exit i2c_adap_imx_exit(void) 1263 { 1264 platform_driver_unregister(&i2c_imx_driver); 1265 } 1266 module_exit(i2c_adap_imx_exit); 1267 1268 MODULE_LICENSE("GPL"); 1269 MODULE_AUTHOR("Darius Augulis"); 1270 MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus"); 1271 MODULE_ALIAS("platform:" DRIVER_NAME); 1272