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 * Author: 15 * Darius Augulis, Teltonika Inc. 16 * 17 * Desc.: 18 * Implementation of I2C Adapter/Algorithm Driver 19 * for I2C Bus integrated in Freescale i.MX/MXC processors 20 * 21 * Derived from Motorola GSG China I2C example driver 22 * 23 * Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de 24 * Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de 25 * Copyright (C) 2007 RightHand Technologies, Inc. 26 * Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt> 27 * 28 * Copyright 2013 Freescale Semiconductor, Inc. 29 * 30 */ 31 32 #include <linux/clk.h> 33 #include <linux/completion.h> 34 #include <linux/delay.h> 35 #include <linux/dma-mapping.h> 36 #include <linux/dmaengine.h> 37 #include <linux/dmapool.h> 38 #include <linux/err.h> 39 #include <linux/errno.h> 40 #include <linux/i2c.h> 41 #include <linux/init.h> 42 #include <linux/interrupt.h> 43 #include <linux/io.h> 44 #include <linux/kernel.h> 45 #include <linux/module.h> 46 #include <linux/of.h> 47 #include <linux/of_device.h> 48 #include <linux/of_dma.h> 49 #include <linux/of_gpio.h> 50 #include <linux/pinctrl/consumer.h> 51 #include <linux/platform_data/i2c-imx.h> 52 #include <linux/platform_device.h> 53 #include <linux/pm_runtime.h> 54 #include <linux/sched.h> 55 #include <linux/slab.h> 56 57 /* This will be the driver name the kernel reports */ 58 #define DRIVER_NAME "imx-i2c" 59 60 /* Default value */ 61 #define IMX_I2C_BIT_RATE 100000 /* 100kHz */ 62 63 /* 64 * Enable DMA if transfer byte size is bigger than this threshold. 65 * As the hardware request, it must bigger than 4 bytes.\ 66 * I have set '16' here, maybe it's not the best but I think it's 67 * the appropriate. 68 */ 69 #define DMA_THRESHOLD 16 70 #define DMA_TIMEOUT 1000 71 72 /* IMX I2C registers: 73 * the I2C register offset is different between SoCs, 74 * to provid support for all these chips, split the 75 * register offset into a fixed base address and a 76 * variable shift value, then the full register offset 77 * will be calculated by 78 * reg_off = ( reg_base_addr << reg_shift) 79 */ 80 #define IMX_I2C_IADR 0x00 /* i2c slave address */ 81 #define IMX_I2C_IFDR 0x01 /* i2c frequency divider */ 82 #define IMX_I2C_I2CR 0x02 /* i2c control */ 83 #define IMX_I2C_I2SR 0x03 /* i2c status */ 84 #define IMX_I2C_I2DR 0x04 /* i2c transfer data */ 85 86 #define IMX_I2C_REGSHIFT 2 87 #define VF610_I2C_REGSHIFT 0 88 89 /* Bits of IMX I2C registers */ 90 #define I2SR_RXAK 0x01 91 #define I2SR_IIF 0x02 92 #define I2SR_SRW 0x04 93 #define I2SR_IAL 0x10 94 #define I2SR_IBB 0x20 95 #define I2SR_IAAS 0x40 96 #define I2SR_ICF 0x80 97 #define I2CR_DMAEN 0x02 98 #define I2CR_RSTA 0x04 99 #define I2CR_TXAK 0x08 100 #define I2CR_MTX 0x10 101 #define I2CR_MSTA 0x20 102 #define I2CR_IIEN 0x40 103 #define I2CR_IEN 0x80 104 105 /* register bits different operating codes definition: 106 * 1) I2SR: Interrupt flags clear operation differ between SoCs: 107 * - write zero to clear(w0c) INT flag on i.MX, 108 * - but write one to clear(w1c) INT flag on Vybrid. 109 * 2) I2CR: I2C module enable operation also differ between SoCs: 110 * - set I2CR_IEN bit enable the module on i.MX, 111 * - but clear I2CR_IEN bit enable the module on Vybrid. 112 */ 113 #define I2SR_CLR_OPCODE_W0C 0x0 114 #define I2SR_CLR_OPCODE_W1C (I2SR_IAL | I2SR_IIF) 115 #define I2CR_IEN_OPCODE_0 0x0 116 #define I2CR_IEN_OPCODE_1 I2CR_IEN 117 118 #define I2C_PM_TIMEOUT 10 /* ms */ 119 120 /* 121 * sorted list of clock divider, register value pairs 122 * taken from table 26-5, p.26-9, Freescale i.MX 123 * Integrated Portable System Processor Reference Manual 124 * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007 125 * 126 * Duplicated divider values removed from list 127 */ 128 struct imx_i2c_clk_pair { 129 u16 div; 130 u16 val; 131 }; 132 133 static struct imx_i2c_clk_pair imx_i2c_clk_div[] = { 134 { 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 }, 135 { 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 }, 136 { 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 }, 137 { 56, 0x29 }, { 60, 0x06 }, { 64, 0x2A }, { 72, 0x2B }, 138 { 80, 0x2C }, { 88, 0x09 }, { 96, 0x2D }, { 104, 0x0A }, 139 { 112, 0x2E }, { 128, 0x2F }, { 144, 0x0C }, { 160, 0x30 }, 140 { 192, 0x31 }, { 224, 0x32 }, { 240, 0x0F }, { 256, 0x33 }, 141 { 288, 0x10 }, { 320, 0x34 }, { 384, 0x35 }, { 448, 0x36 }, 142 { 480, 0x13 }, { 512, 0x37 }, { 576, 0x14 }, { 640, 0x38 }, 143 { 768, 0x39 }, { 896, 0x3A }, { 960, 0x17 }, { 1024, 0x3B }, 144 { 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E }, 145 { 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D }, 146 { 3072, 0x1E }, { 3840, 0x1F } 147 }; 148 149 /* Vybrid VF610 clock divider, register value pairs */ 150 static struct imx_i2c_clk_pair vf610_i2c_clk_div[] = { 151 { 20, 0x00 }, { 22, 0x01 }, { 24, 0x02 }, { 26, 0x03 }, 152 { 28, 0x04 }, { 30, 0x05 }, { 32, 0x09 }, { 34, 0x06 }, 153 { 36, 0x0A }, { 40, 0x07 }, { 44, 0x0C }, { 48, 0x0D }, 154 { 52, 0x43 }, { 56, 0x0E }, { 60, 0x45 }, { 64, 0x12 }, 155 { 68, 0x0F }, { 72, 0x13 }, { 80, 0x14 }, { 88, 0x15 }, 156 { 96, 0x19 }, { 104, 0x16 }, { 112, 0x1A }, { 128, 0x17 }, 157 { 136, 0x4F }, { 144, 0x1C }, { 160, 0x1D }, { 176, 0x55 }, 158 { 192, 0x1E }, { 208, 0x56 }, { 224, 0x22 }, { 228, 0x24 }, 159 { 240, 0x1F }, { 256, 0x23 }, { 288, 0x5C }, { 320, 0x25 }, 160 { 384, 0x26 }, { 448, 0x2A }, { 480, 0x27 }, { 512, 0x2B }, 161 { 576, 0x2C }, { 640, 0x2D }, { 768, 0x31 }, { 896, 0x32 }, 162 { 960, 0x2F }, { 1024, 0x33 }, { 1152, 0x34 }, { 1280, 0x35 }, 163 { 1536, 0x36 }, { 1792, 0x3A }, { 1920, 0x37 }, { 2048, 0x3B }, 164 { 2304, 0x3C }, { 2560, 0x3D }, { 3072, 0x3E }, { 3584, 0x7A }, 165 { 3840, 0x3F }, { 4096, 0x7B }, { 5120, 0x7D }, { 6144, 0x7E }, 166 }; 167 168 enum imx_i2c_type { 169 IMX1_I2C, 170 IMX21_I2C, 171 VF610_I2C, 172 }; 173 174 struct imx_i2c_hwdata { 175 enum imx_i2c_type devtype; 176 unsigned regshift; 177 struct imx_i2c_clk_pair *clk_div; 178 unsigned ndivs; 179 unsigned i2sr_clr_opcode; 180 unsigned i2cr_ien_opcode; 181 }; 182 183 struct imx_i2c_dma { 184 struct dma_chan *chan_tx; 185 struct dma_chan *chan_rx; 186 struct dma_chan *chan_using; 187 struct completion cmd_complete; 188 dma_addr_t dma_buf; 189 unsigned int dma_len; 190 enum dma_transfer_direction dma_transfer_dir; 191 enum dma_data_direction dma_data_dir; 192 }; 193 194 struct imx_i2c_struct { 195 struct i2c_adapter adapter; 196 struct clk *clk; 197 void __iomem *base; 198 wait_queue_head_t queue; 199 unsigned long i2csr; 200 unsigned int disable_delay; 201 int stopped; 202 unsigned int ifdr; /* IMX_I2C_IFDR */ 203 unsigned int cur_clk; 204 unsigned int bitrate; 205 const struct imx_i2c_hwdata *hwdata; 206 struct i2c_bus_recovery_info rinfo; 207 208 struct pinctrl *pinctrl; 209 struct pinctrl_state *pinctrl_pins_default; 210 struct pinctrl_state *pinctrl_pins_gpio; 211 212 struct imx_i2c_dma *dma; 213 }; 214 215 static const struct imx_i2c_hwdata imx1_i2c_hwdata = { 216 .devtype = IMX1_I2C, 217 .regshift = IMX_I2C_REGSHIFT, 218 .clk_div = imx_i2c_clk_div, 219 .ndivs = ARRAY_SIZE(imx_i2c_clk_div), 220 .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C, 221 .i2cr_ien_opcode = I2CR_IEN_OPCODE_1, 222 223 }; 224 225 static const struct imx_i2c_hwdata imx21_i2c_hwdata = { 226 .devtype = IMX21_I2C, 227 .regshift = IMX_I2C_REGSHIFT, 228 .clk_div = imx_i2c_clk_div, 229 .ndivs = ARRAY_SIZE(imx_i2c_clk_div), 230 .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C, 231 .i2cr_ien_opcode = I2CR_IEN_OPCODE_1, 232 233 }; 234 235 static struct imx_i2c_hwdata vf610_i2c_hwdata = { 236 .devtype = VF610_I2C, 237 .regshift = VF610_I2C_REGSHIFT, 238 .clk_div = vf610_i2c_clk_div, 239 .ndivs = ARRAY_SIZE(vf610_i2c_clk_div), 240 .i2sr_clr_opcode = I2SR_CLR_OPCODE_W1C, 241 .i2cr_ien_opcode = I2CR_IEN_OPCODE_0, 242 243 }; 244 245 static const struct platform_device_id imx_i2c_devtype[] = { 246 { 247 .name = "imx1-i2c", 248 .driver_data = (kernel_ulong_t)&imx1_i2c_hwdata, 249 }, { 250 .name = "imx21-i2c", 251 .driver_data = (kernel_ulong_t)&imx21_i2c_hwdata, 252 }, { 253 /* sentinel */ 254 } 255 }; 256 MODULE_DEVICE_TABLE(platform, imx_i2c_devtype); 257 258 static const struct of_device_id i2c_imx_dt_ids[] = { 259 { .compatible = "fsl,imx1-i2c", .data = &imx1_i2c_hwdata, }, 260 { .compatible = "fsl,imx21-i2c", .data = &imx21_i2c_hwdata, }, 261 { .compatible = "fsl,vf610-i2c", .data = &vf610_i2c_hwdata, }, 262 { /* sentinel */ } 263 }; 264 MODULE_DEVICE_TABLE(of, i2c_imx_dt_ids); 265 266 static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx) 267 { 268 return i2c_imx->hwdata->devtype == IMX1_I2C; 269 } 270 271 static inline void imx_i2c_write_reg(unsigned int val, 272 struct imx_i2c_struct *i2c_imx, unsigned int reg) 273 { 274 writeb(val, i2c_imx->base + (reg << i2c_imx->hwdata->regshift)); 275 } 276 277 static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx, 278 unsigned int reg) 279 { 280 return readb(i2c_imx->base + (reg << i2c_imx->hwdata->regshift)); 281 } 282 283 /* Functions for DMA support */ 284 static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx, 285 dma_addr_t phy_addr) 286 { 287 struct imx_i2c_dma *dma; 288 struct dma_slave_config dma_sconfig; 289 struct device *dev = &i2c_imx->adapter.dev; 290 int ret; 291 292 dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL); 293 if (!dma) 294 return; 295 296 dma->chan_tx = dma_request_slave_channel(dev, "tx"); 297 if (!dma->chan_tx) { 298 dev_dbg(dev, "can't request DMA tx channel\n"); 299 goto fail_al; 300 } 301 302 dma_sconfig.dst_addr = phy_addr + 303 (IMX_I2C_I2DR << i2c_imx->hwdata->regshift); 304 dma_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; 305 dma_sconfig.dst_maxburst = 1; 306 dma_sconfig.direction = DMA_MEM_TO_DEV; 307 ret = dmaengine_slave_config(dma->chan_tx, &dma_sconfig); 308 if (ret < 0) { 309 dev_dbg(dev, "can't configure tx channel\n"); 310 goto fail_tx; 311 } 312 313 dma->chan_rx = dma_request_slave_channel(dev, "rx"); 314 if (!dma->chan_rx) { 315 dev_dbg(dev, "can't request DMA rx channel\n"); 316 goto fail_tx; 317 } 318 319 dma_sconfig.src_addr = phy_addr + 320 (IMX_I2C_I2DR << i2c_imx->hwdata->regshift); 321 dma_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; 322 dma_sconfig.src_maxburst = 1; 323 dma_sconfig.direction = DMA_DEV_TO_MEM; 324 ret = dmaengine_slave_config(dma->chan_rx, &dma_sconfig); 325 if (ret < 0) { 326 dev_dbg(dev, "can't configure rx channel\n"); 327 goto fail_rx; 328 } 329 330 i2c_imx->dma = dma; 331 init_completion(&dma->cmd_complete); 332 dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n", 333 dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx)); 334 335 return; 336 337 fail_rx: 338 dma_release_channel(dma->chan_rx); 339 fail_tx: 340 dma_release_channel(dma->chan_tx); 341 fail_al: 342 devm_kfree(dev, dma); 343 dev_info(dev, "can't use DMA, using PIO instead.\n"); 344 } 345 346 static void i2c_imx_dma_callback(void *arg) 347 { 348 struct imx_i2c_struct *i2c_imx = (struct imx_i2c_struct *)arg; 349 struct imx_i2c_dma *dma = i2c_imx->dma; 350 351 dma_unmap_single(dma->chan_using->device->dev, dma->dma_buf, 352 dma->dma_len, dma->dma_data_dir); 353 complete(&dma->cmd_complete); 354 } 355 356 static int i2c_imx_dma_xfer(struct imx_i2c_struct *i2c_imx, 357 struct i2c_msg *msgs) 358 { 359 struct imx_i2c_dma *dma = i2c_imx->dma; 360 struct dma_async_tx_descriptor *txdesc; 361 struct device *dev = &i2c_imx->adapter.dev; 362 struct device *chan_dev = dma->chan_using->device->dev; 363 364 dma->dma_buf = dma_map_single(chan_dev, msgs->buf, 365 dma->dma_len, dma->dma_data_dir); 366 if (dma_mapping_error(chan_dev, dma->dma_buf)) { 367 dev_err(dev, "DMA mapping failed\n"); 368 goto err_map; 369 } 370 371 txdesc = dmaengine_prep_slave_single(dma->chan_using, dma->dma_buf, 372 dma->dma_len, dma->dma_transfer_dir, 373 DMA_PREP_INTERRUPT | DMA_CTRL_ACK); 374 if (!txdesc) { 375 dev_err(dev, "Not able to get desc for DMA xfer\n"); 376 goto err_desc; 377 } 378 379 txdesc->callback = i2c_imx_dma_callback; 380 txdesc->callback_param = i2c_imx; 381 if (dma_submit_error(dmaengine_submit(txdesc))) { 382 dev_err(dev, "DMA submit failed\n"); 383 goto err_submit; 384 } 385 386 dma_async_issue_pending(dma->chan_using); 387 return 0; 388 389 err_submit: 390 dmaengine_terminate_all(dma->chan_using); 391 err_desc: 392 dma_unmap_single(chan_dev, dma->dma_buf, 393 dma->dma_len, dma->dma_data_dir); 394 err_map: 395 return -EINVAL; 396 } 397 398 static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx) 399 { 400 struct imx_i2c_dma *dma = i2c_imx->dma; 401 402 dma->dma_buf = 0; 403 dma->dma_len = 0; 404 405 dma_release_channel(dma->chan_tx); 406 dma->chan_tx = NULL; 407 408 dma_release_channel(dma->chan_rx); 409 dma->chan_rx = NULL; 410 411 dma->chan_using = NULL; 412 } 413 414 static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy) 415 { 416 unsigned long orig_jiffies = jiffies; 417 unsigned int temp; 418 419 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 420 421 while (1) { 422 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); 423 424 /* check for arbitration lost */ 425 if (temp & I2SR_IAL) { 426 temp &= ~I2SR_IAL; 427 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); 428 return -EAGAIN; 429 } 430 431 if (for_busy && (temp & I2SR_IBB)) 432 break; 433 if (!for_busy && !(temp & I2SR_IBB)) 434 break; 435 if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) { 436 dev_dbg(&i2c_imx->adapter.dev, 437 "<%s> I2C bus is busy\n", __func__); 438 return -ETIMEDOUT; 439 } 440 schedule(); 441 } 442 443 return 0; 444 } 445 446 static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx) 447 { 448 wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10); 449 450 if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) { 451 dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__); 452 return -ETIMEDOUT; 453 } 454 dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__); 455 i2c_imx->i2csr = 0; 456 return 0; 457 } 458 459 static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx) 460 { 461 if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) { 462 dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__); 463 return -ENXIO; /* No ACK */ 464 } 465 466 dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__); 467 return 0; 468 } 469 470 static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx) 471 { 472 struct imx_i2c_clk_pair *i2c_clk_div = i2c_imx->hwdata->clk_div; 473 unsigned int i2c_clk_rate; 474 unsigned int div; 475 int i; 476 477 /* Divider value calculation */ 478 i2c_clk_rate = clk_get_rate(i2c_imx->clk); 479 if (i2c_imx->cur_clk == i2c_clk_rate) 480 return; 481 482 i2c_imx->cur_clk = i2c_clk_rate; 483 484 div = (i2c_clk_rate + i2c_imx->bitrate - 1) / i2c_imx->bitrate; 485 if (div < i2c_clk_div[0].div) 486 i = 0; 487 else if (div > i2c_clk_div[i2c_imx->hwdata->ndivs - 1].div) 488 i = i2c_imx->hwdata->ndivs - 1; 489 else 490 for (i = 0; i2c_clk_div[i].div < div; i++) 491 ; 492 493 /* Store divider value */ 494 i2c_imx->ifdr = i2c_clk_div[i].val; 495 496 /* 497 * There dummy delay is calculated. 498 * It should be about one I2C clock period long. 499 * This delay is used in I2C bus disable function 500 * to fix chip hardware bug. 501 */ 502 i2c_imx->disable_delay = (500000U * i2c_clk_div[i].div 503 + (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2); 504 505 #ifdef CONFIG_I2C_DEBUG_BUS 506 dev_dbg(&i2c_imx->adapter.dev, "I2C_CLK=%d, REQ DIV=%d\n", 507 i2c_clk_rate, div); 508 dev_dbg(&i2c_imx->adapter.dev, "IFDR[IC]=0x%x, REAL DIV=%d\n", 509 i2c_clk_div[i].val, i2c_clk_div[i].div); 510 #endif 511 } 512 513 static int i2c_imx_start(struct imx_i2c_struct *i2c_imx) 514 { 515 unsigned int temp = 0; 516 int result; 517 518 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 519 520 i2c_imx_set_clk(i2c_imx); 521 522 imx_i2c_write_reg(i2c_imx->ifdr, i2c_imx, IMX_I2C_IFDR); 523 /* Enable I2C controller */ 524 imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR); 525 imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode, i2c_imx, IMX_I2C_I2CR); 526 527 /* Wait controller to be stable */ 528 usleep_range(50, 150); 529 530 /* Start I2C transaction */ 531 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 532 temp |= I2CR_MSTA; 533 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 534 result = i2c_imx_bus_busy(i2c_imx, 1); 535 if (result) 536 return result; 537 i2c_imx->stopped = 0; 538 539 temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK; 540 temp &= ~I2CR_DMAEN; 541 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 542 return result; 543 } 544 545 static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx) 546 { 547 unsigned int temp = 0; 548 549 if (!i2c_imx->stopped) { 550 /* Stop I2C transaction */ 551 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 552 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 553 temp &= ~(I2CR_MSTA | I2CR_MTX); 554 if (i2c_imx->dma) 555 temp &= ~I2CR_DMAEN; 556 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 557 } 558 if (is_imx1_i2c(i2c_imx)) { 559 /* 560 * This delay caused by an i.MXL hardware bug. 561 * If no (or too short) delay, no "STOP" bit will be generated. 562 */ 563 udelay(i2c_imx->disable_delay); 564 } 565 566 if (!i2c_imx->stopped) { 567 i2c_imx_bus_busy(i2c_imx, 0); 568 i2c_imx->stopped = 1; 569 } 570 571 /* Disable I2C controller */ 572 temp = i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN, 573 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 574 } 575 576 static irqreturn_t i2c_imx_isr(int irq, void *dev_id) 577 { 578 struct imx_i2c_struct *i2c_imx = dev_id; 579 unsigned int temp; 580 581 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); 582 if (temp & I2SR_IIF) { 583 /* save status register */ 584 i2c_imx->i2csr = temp; 585 temp &= ~I2SR_IIF; 586 temp |= (i2c_imx->hwdata->i2sr_clr_opcode & I2SR_IIF); 587 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR); 588 wake_up(&i2c_imx->queue); 589 return IRQ_HANDLED; 590 } 591 592 return IRQ_NONE; 593 } 594 595 static int i2c_imx_dma_write(struct imx_i2c_struct *i2c_imx, 596 struct i2c_msg *msgs) 597 { 598 int result; 599 unsigned long time_left; 600 unsigned int temp = 0; 601 unsigned long orig_jiffies = jiffies; 602 struct imx_i2c_dma *dma = i2c_imx->dma; 603 struct device *dev = &i2c_imx->adapter.dev; 604 605 dma->chan_using = dma->chan_tx; 606 dma->dma_transfer_dir = DMA_MEM_TO_DEV; 607 dma->dma_data_dir = DMA_TO_DEVICE; 608 dma->dma_len = msgs->len - 1; 609 result = i2c_imx_dma_xfer(i2c_imx, msgs); 610 if (result) 611 return result; 612 613 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 614 temp |= I2CR_DMAEN; 615 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 616 617 /* 618 * Write slave address. 619 * The first byte must be transmitted by the CPU. 620 */ 621 imx_i2c_write_reg(msgs->addr << 1, i2c_imx, IMX_I2C_I2DR); 622 reinit_completion(&i2c_imx->dma->cmd_complete); 623 time_left = wait_for_completion_timeout( 624 &i2c_imx->dma->cmd_complete, 625 msecs_to_jiffies(DMA_TIMEOUT)); 626 if (time_left == 0) { 627 dmaengine_terminate_all(dma->chan_using); 628 return -ETIMEDOUT; 629 } 630 631 /* Waiting for transfer complete. */ 632 while (1) { 633 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); 634 if (temp & I2SR_ICF) 635 break; 636 if (time_after(jiffies, orig_jiffies + 637 msecs_to_jiffies(DMA_TIMEOUT))) { 638 dev_dbg(dev, "<%s> Timeout\n", __func__); 639 return -ETIMEDOUT; 640 } 641 schedule(); 642 } 643 644 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 645 temp &= ~I2CR_DMAEN; 646 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 647 648 /* The last data byte must be transferred by the CPU. */ 649 imx_i2c_write_reg(msgs->buf[msgs->len-1], 650 i2c_imx, IMX_I2C_I2DR); 651 result = i2c_imx_trx_complete(i2c_imx); 652 if (result) 653 return result; 654 655 return i2c_imx_acked(i2c_imx); 656 } 657 658 static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx, 659 struct i2c_msg *msgs, bool is_lastmsg) 660 { 661 int result; 662 unsigned long time_left; 663 unsigned int temp; 664 unsigned long orig_jiffies = jiffies; 665 struct imx_i2c_dma *dma = i2c_imx->dma; 666 struct device *dev = &i2c_imx->adapter.dev; 667 668 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 669 temp |= I2CR_DMAEN; 670 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 671 672 dma->chan_using = dma->chan_rx; 673 dma->dma_transfer_dir = DMA_DEV_TO_MEM; 674 dma->dma_data_dir = DMA_FROM_DEVICE; 675 /* The last two data bytes must be transferred by the CPU. */ 676 dma->dma_len = msgs->len - 2; 677 result = i2c_imx_dma_xfer(i2c_imx, msgs); 678 if (result) 679 return result; 680 681 reinit_completion(&i2c_imx->dma->cmd_complete); 682 time_left = wait_for_completion_timeout( 683 &i2c_imx->dma->cmd_complete, 684 msecs_to_jiffies(DMA_TIMEOUT)); 685 if (time_left == 0) { 686 dmaengine_terminate_all(dma->chan_using); 687 return -ETIMEDOUT; 688 } 689 690 /* waiting for transfer complete. */ 691 while (1) { 692 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); 693 if (temp & I2SR_ICF) 694 break; 695 if (time_after(jiffies, orig_jiffies + 696 msecs_to_jiffies(DMA_TIMEOUT))) { 697 dev_dbg(dev, "<%s> Timeout\n", __func__); 698 return -ETIMEDOUT; 699 } 700 schedule(); 701 } 702 703 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 704 temp &= ~I2CR_DMAEN; 705 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 706 707 /* read n-1 byte data */ 708 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 709 temp |= I2CR_TXAK; 710 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 711 712 msgs->buf[msgs->len-2] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); 713 /* read n byte data */ 714 result = i2c_imx_trx_complete(i2c_imx); 715 if (result) 716 return result; 717 718 if (is_lastmsg) { 719 /* 720 * It must generate STOP before read I2DR to prevent 721 * controller from generating another clock cycle 722 */ 723 dev_dbg(dev, "<%s> clear MSTA\n", __func__); 724 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 725 temp &= ~(I2CR_MSTA | I2CR_MTX); 726 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 727 i2c_imx_bus_busy(i2c_imx, 0); 728 i2c_imx->stopped = 1; 729 } else { 730 /* 731 * For i2c master receiver repeat restart operation like: 732 * read -> repeat MSTA -> read/write 733 * The controller must set MTX before read the last byte in 734 * the first read operation, otherwise the first read cost 735 * one extra clock cycle. 736 */ 737 temp = readb(i2c_imx->base + IMX_I2C_I2CR); 738 temp |= I2CR_MTX; 739 writeb(temp, i2c_imx->base + IMX_I2C_I2CR); 740 } 741 msgs->buf[msgs->len-1] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); 742 743 return 0; 744 } 745 746 static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs) 747 { 748 int i, result; 749 750 dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n", 751 __func__, msgs->addr << 1); 752 753 /* write slave address */ 754 imx_i2c_write_reg(msgs->addr << 1, i2c_imx, IMX_I2C_I2DR); 755 result = i2c_imx_trx_complete(i2c_imx); 756 if (result) 757 return result; 758 result = i2c_imx_acked(i2c_imx); 759 if (result) 760 return result; 761 dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__); 762 763 /* write data */ 764 for (i = 0; i < msgs->len; i++) { 765 dev_dbg(&i2c_imx->adapter.dev, 766 "<%s> write byte: B%d=0x%X\n", 767 __func__, i, msgs->buf[i]); 768 imx_i2c_write_reg(msgs->buf[i], i2c_imx, IMX_I2C_I2DR); 769 result = i2c_imx_trx_complete(i2c_imx); 770 if (result) 771 return result; 772 result = i2c_imx_acked(i2c_imx); 773 if (result) 774 return result; 775 } 776 return 0; 777 } 778 779 static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, bool is_lastmsg) 780 { 781 int i, result; 782 unsigned int temp; 783 int block_data = msgs->flags & I2C_M_RECV_LEN; 784 785 dev_dbg(&i2c_imx->adapter.dev, 786 "<%s> write slave address: addr=0x%x\n", 787 __func__, (msgs->addr << 1) | 0x01); 788 789 /* write slave address */ 790 imx_i2c_write_reg((msgs->addr << 1) | 0x01, i2c_imx, IMX_I2C_I2DR); 791 result = i2c_imx_trx_complete(i2c_imx); 792 if (result) 793 return result; 794 result = i2c_imx_acked(i2c_imx); 795 if (result) 796 return result; 797 798 dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__); 799 800 /* setup bus to read data */ 801 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 802 temp &= ~I2CR_MTX; 803 804 /* 805 * Reset the I2CR_TXAK flag initially for SMBus block read since the 806 * length is unknown 807 */ 808 if ((msgs->len - 1) || block_data) 809 temp &= ~I2CR_TXAK; 810 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 811 imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */ 812 813 dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__); 814 815 if (i2c_imx->dma && msgs->len >= DMA_THRESHOLD && !block_data) 816 return i2c_imx_dma_read(i2c_imx, msgs, is_lastmsg); 817 818 /* read data */ 819 for (i = 0; i < msgs->len; i++) { 820 u8 len = 0; 821 822 result = i2c_imx_trx_complete(i2c_imx); 823 if (result) 824 return result; 825 /* 826 * First byte is the length of remaining packet 827 * in the SMBus block data read. Add it to 828 * msgs->len. 829 */ 830 if ((!i) && block_data) { 831 len = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); 832 if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX)) 833 return -EPROTO; 834 dev_dbg(&i2c_imx->adapter.dev, 835 "<%s> read length: 0x%X\n", 836 __func__, len); 837 msgs->len += len; 838 } 839 if (i == (msgs->len - 1)) { 840 if (is_lastmsg) { 841 /* 842 * It must generate STOP before read I2DR to prevent 843 * controller from generating another clock cycle 844 */ 845 dev_dbg(&i2c_imx->adapter.dev, 846 "<%s> clear MSTA\n", __func__); 847 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 848 temp &= ~(I2CR_MSTA | I2CR_MTX); 849 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 850 i2c_imx_bus_busy(i2c_imx, 0); 851 i2c_imx->stopped = 1; 852 } else { 853 /* 854 * For i2c master receiver repeat restart operation like: 855 * read -> repeat MSTA -> read/write 856 * The controller must set MTX before read the last byte in 857 * the first read operation, otherwise the first read cost 858 * one extra clock cycle. 859 */ 860 temp = readb(i2c_imx->base + IMX_I2C_I2CR); 861 temp |= I2CR_MTX; 862 writeb(temp, i2c_imx->base + IMX_I2C_I2CR); 863 } 864 } else if (i == (msgs->len - 2)) { 865 dev_dbg(&i2c_imx->adapter.dev, 866 "<%s> set TXAK\n", __func__); 867 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 868 temp |= I2CR_TXAK; 869 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 870 } 871 if ((!i) && block_data) 872 msgs->buf[0] = len; 873 else 874 msgs->buf[i] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); 875 dev_dbg(&i2c_imx->adapter.dev, 876 "<%s> read byte: B%d=0x%X\n", 877 __func__, i, msgs->buf[i]); 878 } 879 return 0; 880 } 881 882 static int i2c_imx_xfer(struct i2c_adapter *adapter, 883 struct i2c_msg *msgs, int num) 884 { 885 unsigned int i, temp; 886 int result; 887 bool is_lastmsg = false; 888 struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter); 889 890 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__); 891 892 result = pm_runtime_get_sync(i2c_imx->adapter.dev.parent); 893 if (result < 0) 894 goto out; 895 896 /* Start I2C transfer */ 897 result = i2c_imx_start(i2c_imx); 898 if (result) { 899 if (i2c_imx->adapter.bus_recovery_info) { 900 i2c_recover_bus(&i2c_imx->adapter); 901 result = i2c_imx_start(i2c_imx); 902 } 903 } 904 905 if (result) 906 goto fail0; 907 908 /* read/write data */ 909 for (i = 0; i < num; i++) { 910 if (i == num - 1) 911 is_lastmsg = true; 912 913 if (i) { 914 dev_dbg(&i2c_imx->adapter.dev, 915 "<%s> repeated start\n", __func__); 916 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 917 temp |= I2CR_RSTA; 918 imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); 919 result = i2c_imx_bus_busy(i2c_imx, 1); 920 if (result) 921 goto fail0; 922 } 923 dev_dbg(&i2c_imx->adapter.dev, 924 "<%s> transfer message: %d\n", __func__, i); 925 /* write/read data */ 926 #ifdef CONFIG_I2C_DEBUG_BUS 927 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); 928 dev_dbg(&i2c_imx->adapter.dev, 929 "<%s> CONTROL: IEN=%d, IIEN=%d, MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n", 930 __func__, 931 (temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0), 932 (temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0), 933 (temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0)); 934 temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); 935 dev_dbg(&i2c_imx->adapter.dev, 936 "<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n", 937 __func__, 938 (temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0), 939 (temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0), 940 (temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0), 941 (temp & I2SR_RXAK ? 1 : 0)); 942 #endif 943 if (msgs[i].flags & I2C_M_RD) 944 result = i2c_imx_read(i2c_imx, &msgs[i], is_lastmsg); 945 else { 946 if (i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD) 947 result = i2c_imx_dma_write(i2c_imx, &msgs[i]); 948 else 949 result = i2c_imx_write(i2c_imx, &msgs[i]); 950 } 951 if (result) 952 goto fail0; 953 } 954 955 fail0: 956 /* Stop I2C transfer */ 957 i2c_imx_stop(i2c_imx); 958 959 pm_runtime_mark_last_busy(i2c_imx->adapter.dev.parent); 960 pm_runtime_put_autosuspend(i2c_imx->adapter.dev.parent); 961 962 out: 963 dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__, 964 (result < 0) ? "error" : "success msg", 965 (result < 0) ? result : num); 966 return (result < 0) ? result : num; 967 } 968 969 static void i2c_imx_prepare_recovery(struct i2c_adapter *adap) 970 { 971 struct imx_i2c_struct *i2c_imx; 972 973 i2c_imx = container_of(adap, struct imx_i2c_struct, adapter); 974 975 pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_gpio); 976 } 977 978 static void i2c_imx_unprepare_recovery(struct i2c_adapter *adap) 979 { 980 struct imx_i2c_struct *i2c_imx; 981 982 i2c_imx = container_of(adap, struct imx_i2c_struct, adapter); 983 984 pinctrl_select_state(i2c_imx->pinctrl, i2c_imx->pinctrl_pins_default); 985 } 986 987 /* 988 * We switch SCL and SDA to their GPIO function and do some bitbanging 989 * for bus recovery. These alternative pinmux settings can be 990 * described in the device tree by a separate pinctrl state "gpio". If 991 * this is missing this is not a big problem, the only implication is 992 * that we can't do bus recovery. 993 */ 994 static int i2c_imx_init_recovery_info(struct imx_i2c_struct *i2c_imx, 995 struct platform_device *pdev) 996 { 997 struct i2c_bus_recovery_info *rinfo = &i2c_imx->rinfo; 998 999 i2c_imx->pinctrl = devm_pinctrl_get(&pdev->dev); 1000 if (!i2c_imx->pinctrl || IS_ERR(i2c_imx->pinctrl)) { 1001 dev_info(&pdev->dev, "can't get pinctrl, bus recovery not supported\n"); 1002 return PTR_ERR(i2c_imx->pinctrl); 1003 } 1004 1005 i2c_imx->pinctrl_pins_default = pinctrl_lookup_state(i2c_imx->pinctrl, 1006 PINCTRL_STATE_DEFAULT); 1007 i2c_imx->pinctrl_pins_gpio = pinctrl_lookup_state(i2c_imx->pinctrl, 1008 "gpio"); 1009 rinfo->sda_gpio = of_get_named_gpio(pdev->dev.of_node, "sda-gpios", 0); 1010 rinfo->scl_gpio = of_get_named_gpio(pdev->dev.of_node, "scl-gpios", 0); 1011 1012 if (rinfo->sda_gpio == -EPROBE_DEFER || 1013 rinfo->scl_gpio == -EPROBE_DEFER) { 1014 return -EPROBE_DEFER; 1015 } else if (!gpio_is_valid(rinfo->sda_gpio) || 1016 !gpio_is_valid(rinfo->scl_gpio) || 1017 IS_ERR(i2c_imx->pinctrl_pins_default) || 1018 IS_ERR(i2c_imx->pinctrl_pins_gpio)) { 1019 dev_dbg(&pdev->dev, "recovery information incomplete\n"); 1020 return 0; 1021 } 1022 1023 dev_dbg(&pdev->dev, "using scl-gpio %d and sda-gpio %d for recovery\n", 1024 rinfo->sda_gpio, rinfo->scl_gpio); 1025 1026 rinfo->prepare_recovery = i2c_imx_prepare_recovery; 1027 rinfo->unprepare_recovery = i2c_imx_unprepare_recovery; 1028 rinfo->recover_bus = i2c_generic_gpio_recovery; 1029 i2c_imx->adapter.bus_recovery_info = rinfo; 1030 1031 return 0; 1032 } 1033 1034 static u32 i2c_imx_func(struct i2c_adapter *adapter) 1035 { 1036 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL 1037 | I2C_FUNC_SMBUS_READ_BLOCK_DATA; 1038 } 1039 1040 static struct i2c_algorithm i2c_imx_algo = { 1041 .master_xfer = i2c_imx_xfer, 1042 .functionality = i2c_imx_func, 1043 }; 1044 1045 static int i2c_imx_probe(struct platform_device *pdev) 1046 { 1047 const struct of_device_id *of_id = of_match_device(i2c_imx_dt_ids, 1048 &pdev->dev); 1049 struct imx_i2c_struct *i2c_imx; 1050 struct resource *res; 1051 struct imxi2c_platform_data *pdata = dev_get_platdata(&pdev->dev); 1052 void __iomem *base; 1053 int irq, ret; 1054 dma_addr_t phy_addr; 1055 1056 dev_dbg(&pdev->dev, "<%s>\n", __func__); 1057 1058 irq = platform_get_irq(pdev, 0); 1059 if (irq < 0) { 1060 dev_err(&pdev->dev, "can't get irq number\n"); 1061 return irq; 1062 } 1063 1064 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1065 base = devm_ioremap_resource(&pdev->dev, res); 1066 if (IS_ERR(base)) 1067 return PTR_ERR(base); 1068 1069 phy_addr = (dma_addr_t)res->start; 1070 i2c_imx = devm_kzalloc(&pdev->dev, sizeof(*i2c_imx), GFP_KERNEL); 1071 if (!i2c_imx) 1072 return -ENOMEM; 1073 1074 if (of_id) 1075 i2c_imx->hwdata = of_id->data; 1076 else 1077 i2c_imx->hwdata = (struct imx_i2c_hwdata *) 1078 platform_get_device_id(pdev)->driver_data; 1079 1080 /* Setup i2c_imx driver structure */ 1081 strlcpy(i2c_imx->adapter.name, pdev->name, sizeof(i2c_imx->adapter.name)); 1082 i2c_imx->adapter.owner = THIS_MODULE; 1083 i2c_imx->adapter.algo = &i2c_imx_algo; 1084 i2c_imx->adapter.dev.parent = &pdev->dev; 1085 i2c_imx->adapter.nr = pdev->id; 1086 i2c_imx->adapter.dev.of_node = pdev->dev.of_node; 1087 i2c_imx->base = base; 1088 1089 /* Get I2C clock */ 1090 i2c_imx->clk = devm_clk_get(&pdev->dev, NULL); 1091 if (IS_ERR(i2c_imx->clk)) { 1092 dev_err(&pdev->dev, "can't get I2C clock\n"); 1093 return PTR_ERR(i2c_imx->clk); 1094 } 1095 1096 ret = clk_prepare_enable(i2c_imx->clk); 1097 if (ret) { 1098 dev_err(&pdev->dev, "can't enable I2C clock, ret=%d\n", ret); 1099 return ret; 1100 } 1101 1102 /* Request IRQ */ 1103 ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0, 1104 pdev->name, i2c_imx); 1105 if (ret) { 1106 dev_err(&pdev->dev, "can't claim irq %d\n", irq); 1107 goto clk_disable; 1108 } 1109 1110 /* Init queue */ 1111 init_waitqueue_head(&i2c_imx->queue); 1112 1113 /* Set up adapter data */ 1114 i2c_set_adapdata(&i2c_imx->adapter, i2c_imx); 1115 1116 /* Set up platform driver data */ 1117 platform_set_drvdata(pdev, i2c_imx); 1118 1119 pm_runtime_set_autosuspend_delay(&pdev->dev, I2C_PM_TIMEOUT); 1120 pm_runtime_use_autosuspend(&pdev->dev); 1121 pm_runtime_set_active(&pdev->dev); 1122 pm_runtime_enable(&pdev->dev); 1123 1124 ret = pm_runtime_get_sync(&pdev->dev); 1125 if (ret < 0) 1126 goto rpm_disable; 1127 1128 /* Set up clock divider */ 1129 i2c_imx->bitrate = IMX_I2C_BIT_RATE; 1130 ret = of_property_read_u32(pdev->dev.of_node, 1131 "clock-frequency", &i2c_imx->bitrate); 1132 if (ret < 0 && pdata && pdata->bitrate) 1133 i2c_imx->bitrate = pdata->bitrate; 1134 1135 /* Set up chip registers to defaults */ 1136 imx_i2c_write_reg(i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN, 1137 i2c_imx, IMX_I2C_I2CR); 1138 imx_i2c_write_reg(i2c_imx->hwdata->i2sr_clr_opcode, i2c_imx, IMX_I2C_I2SR); 1139 1140 /* Init optional bus recovery function */ 1141 ret = i2c_imx_init_recovery_info(i2c_imx, pdev); 1142 /* Give it another chance if pinctrl used is not ready yet */ 1143 if (ret == -EPROBE_DEFER) 1144 goto rpm_disable; 1145 1146 /* Add I2C adapter */ 1147 ret = i2c_add_numbered_adapter(&i2c_imx->adapter); 1148 if (ret < 0) 1149 goto rpm_disable; 1150 1151 pm_runtime_mark_last_busy(&pdev->dev); 1152 pm_runtime_put_autosuspend(&pdev->dev); 1153 1154 dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq); 1155 dev_dbg(&i2c_imx->adapter.dev, "device resources: %pR\n", res); 1156 dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n", 1157 i2c_imx->adapter.name); 1158 dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n"); 1159 1160 /* Init DMA config if supported */ 1161 i2c_imx_dma_request(i2c_imx, phy_addr); 1162 1163 return 0; /* Return OK */ 1164 1165 rpm_disable: 1166 pm_runtime_put_noidle(&pdev->dev); 1167 pm_runtime_disable(&pdev->dev); 1168 pm_runtime_set_suspended(&pdev->dev); 1169 pm_runtime_dont_use_autosuspend(&pdev->dev); 1170 1171 clk_disable: 1172 clk_disable_unprepare(i2c_imx->clk); 1173 return ret; 1174 } 1175 1176 static int i2c_imx_remove(struct platform_device *pdev) 1177 { 1178 struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev); 1179 int ret; 1180 1181 ret = pm_runtime_get_sync(&pdev->dev); 1182 if (ret < 0) 1183 return ret; 1184 1185 /* remove adapter */ 1186 dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n"); 1187 i2c_del_adapter(&i2c_imx->adapter); 1188 1189 if (i2c_imx->dma) 1190 i2c_imx_dma_free(i2c_imx); 1191 1192 /* setup chip registers to defaults */ 1193 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR); 1194 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IFDR); 1195 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR); 1196 imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR); 1197 1198 clk_disable_unprepare(i2c_imx->clk); 1199 1200 pm_runtime_put_noidle(&pdev->dev); 1201 pm_runtime_disable(&pdev->dev); 1202 1203 return 0; 1204 } 1205 1206 #ifdef CONFIG_PM 1207 static int i2c_imx_runtime_suspend(struct device *dev) 1208 { 1209 struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev); 1210 1211 clk_disable_unprepare(i2c_imx->clk); 1212 1213 return 0; 1214 } 1215 1216 static int i2c_imx_runtime_resume(struct device *dev) 1217 { 1218 struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev); 1219 int ret; 1220 1221 ret = clk_prepare_enable(i2c_imx->clk); 1222 if (ret) 1223 dev_err(dev, "can't enable I2C clock, ret=%d\n", ret); 1224 1225 return ret; 1226 } 1227 1228 static const struct dev_pm_ops i2c_imx_pm_ops = { 1229 SET_RUNTIME_PM_OPS(i2c_imx_runtime_suspend, 1230 i2c_imx_runtime_resume, NULL) 1231 }; 1232 #define I2C_IMX_PM_OPS (&i2c_imx_pm_ops) 1233 #else 1234 #define I2C_IMX_PM_OPS NULL 1235 #endif /* CONFIG_PM */ 1236 1237 static struct platform_driver i2c_imx_driver = { 1238 .probe = i2c_imx_probe, 1239 .remove = i2c_imx_remove, 1240 .driver = { 1241 .name = DRIVER_NAME, 1242 .pm = I2C_IMX_PM_OPS, 1243 .of_match_table = i2c_imx_dt_ids, 1244 }, 1245 .id_table = imx_i2c_devtype, 1246 }; 1247 1248 static int __init i2c_adap_imx_init(void) 1249 { 1250 return platform_driver_register(&i2c_imx_driver); 1251 } 1252 subsys_initcall(i2c_adap_imx_init); 1253 1254 static void __exit i2c_adap_imx_exit(void) 1255 { 1256 platform_driver_unregister(&i2c_imx_driver); 1257 } 1258 module_exit(i2c_adap_imx_exit); 1259 1260 MODULE_LICENSE("GPL"); 1261 MODULE_AUTHOR("Darius Augulis"); 1262 MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus"); 1263 MODULE_ALIAS("platform:" DRIVER_NAME); 1264