1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Driver for STMicroelectronics STM32F7 I2C controller 4 * 5 * This I2C controller is described in the STM32F75xxx and STM32F74xxx Soc 6 * reference manual. 7 * Please see below a link to the documentation: 8 * http://www.st.com/resource/en/reference_manual/dm00124865.pdf 9 * 10 * Copyright (C) M'boumba Cedric Madianga 2017 11 * Copyright (C) STMicroelectronics 2017 12 * Author: M'boumba Cedric Madianga <cedric.madianga@gmail.com> 13 * 14 * This driver is based on i2c-stm32f4.c 15 * 16 */ 17 #include <linux/clk.h> 18 #include <linux/delay.h> 19 #include <linux/err.h> 20 #include <linux/i2c.h> 21 #include <linux/i2c-smbus.h> 22 #include <linux/interrupt.h> 23 #include <linux/io.h> 24 #include <linux/iopoll.h> 25 #include <linux/mfd/syscon.h> 26 #include <linux/module.h> 27 #include <linux/of.h> 28 #include <linux/of_address.h> 29 #include <linux/of_platform.h> 30 #include <linux/platform_device.h> 31 #include <linux/pinctrl/consumer.h> 32 #include <linux/pm_runtime.h> 33 #include <linux/pm_wakeirq.h> 34 #include <linux/regmap.h> 35 #include <linux/reset.h> 36 #include <linux/slab.h> 37 #include <linux/string_choices.h> 38 39 #include "i2c-stm32.h" 40 41 /* STM32F7 I2C registers */ 42 #define STM32F7_I2C_CR1 0x00 43 #define STM32F7_I2C_CR2 0x04 44 #define STM32F7_I2C_OAR1 0x08 45 #define STM32F7_I2C_OAR2 0x0C 46 #define STM32F7_I2C_PECR 0x20 47 #define STM32F7_I2C_TIMINGR 0x10 48 #define STM32F7_I2C_ISR 0x18 49 #define STM32F7_I2C_ICR 0x1C 50 #define STM32F7_I2C_RXDR 0x24 51 #define STM32F7_I2C_TXDR 0x28 52 53 /* STM32F7 I2C control 1 */ 54 #define STM32_I2C_CR1_FMP BIT(24) 55 #define STM32F7_I2C_CR1_PECEN BIT(23) 56 #define STM32F7_I2C_CR1_ALERTEN BIT(22) 57 #define STM32F7_I2C_CR1_SMBHEN BIT(20) 58 #define STM32F7_I2C_CR1_WUPEN BIT(18) 59 #define STM32F7_I2C_CR1_SBC BIT(16) 60 #define STM32F7_I2C_CR1_RXDMAEN BIT(15) 61 #define STM32F7_I2C_CR1_TXDMAEN BIT(14) 62 #define STM32F7_I2C_CR1_ANFOFF BIT(12) 63 #define STM32F7_I2C_CR1_DNF_MASK GENMASK(11, 8) 64 #define STM32F7_I2C_CR1_DNF(n) (((n) & 0xf) << 8) 65 #define STM32F7_I2C_CR1_ERRIE BIT(7) 66 #define STM32F7_I2C_CR1_TCIE BIT(6) 67 #define STM32F7_I2C_CR1_STOPIE BIT(5) 68 #define STM32F7_I2C_CR1_NACKIE BIT(4) 69 #define STM32F7_I2C_CR1_ADDRIE BIT(3) 70 #define STM32F7_I2C_CR1_RXIE BIT(2) 71 #define STM32F7_I2C_CR1_TXIE BIT(1) 72 #define STM32F7_I2C_CR1_PE BIT(0) 73 #define STM32F7_I2C_ALL_IRQ_MASK (STM32F7_I2C_CR1_ERRIE \ 74 | STM32F7_I2C_CR1_TCIE \ 75 | STM32F7_I2C_CR1_STOPIE \ 76 | STM32F7_I2C_CR1_NACKIE \ 77 | STM32F7_I2C_CR1_RXIE \ 78 | STM32F7_I2C_CR1_TXIE) 79 #define STM32F7_I2C_XFER_IRQ_MASK (STM32F7_I2C_CR1_TCIE \ 80 | STM32F7_I2C_CR1_STOPIE \ 81 | STM32F7_I2C_CR1_NACKIE \ 82 | STM32F7_I2C_CR1_RXIE \ 83 | STM32F7_I2C_CR1_TXIE) 84 85 /* STM32F7 I2C control 2 */ 86 #define STM32F7_I2C_CR2_PECBYTE BIT(26) 87 #define STM32F7_I2C_CR2_RELOAD BIT(24) 88 #define STM32F7_I2C_CR2_NBYTES_MASK GENMASK(23, 16) 89 #define STM32F7_I2C_CR2_NBYTES(n) (((n) & 0xff) << 16) 90 #define STM32F7_I2C_CR2_NACK BIT(15) 91 #define STM32F7_I2C_CR2_STOP BIT(14) 92 #define STM32F7_I2C_CR2_START BIT(13) 93 #define STM32F7_I2C_CR2_HEAD10R BIT(12) 94 #define STM32F7_I2C_CR2_ADD10 BIT(11) 95 #define STM32F7_I2C_CR2_RD_WRN BIT(10) 96 #define STM32F7_I2C_CR2_SADD10_MASK GENMASK(9, 0) 97 #define STM32F7_I2C_CR2_SADD10(n) (((n) & \ 98 STM32F7_I2C_CR2_SADD10_MASK)) 99 #define STM32F7_I2C_CR2_SADD7_MASK GENMASK(7, 1) 100 #define STM32F7_I2C_CR2_SADD7(n) (((n) & 0x7f) << 1) 101 102 /* STM32F7 I2C Own Address 1 */ 103 #define STM32F7_I2C_OAR1_OA1EN BIT(15) 104 #define STM32F7_I2C_OAR1_OA1MODE BIT(10) 105 #define STM32F7_I2C_OAR1_OA1_10_MASK GENMASK(9, 0) 106 #define STM32F7_I2C_OAR1_OA1_10(n) (((n) & \ 107 STM32F7_I2C_OAR1_OA1_10_MASK)) 108 #define STM32F7_I2C_OAR1_OA1_7_MASK GENMASK(7, 1) 109 #define STM32F7_I2C_OAR1_OA1_7(n) (((n) & 0x7f) << 1) 110 #define STM32F7_I2C_OAR1_MASK (STM32F7_I2C_OAR1_OA1_7_MASK \ 111 | STM32F7_I2C_OAR1_OA1_10_MASK \ 112 | STM32F7_I2C_OAR1_OA1EN \ 113 | STM32F7_I2C_OAR1_OA1MODE) 114 115 /* STM32F7 I2C Own Address 2 */ 116 #define STM32F7_I2C_OAR2_OA2EN BIT(15) 117 #define STM32F7_I2C_OAR2_OA2MSK_MASK GENMASK(10, 8) 118 #define STM32F7_I2C_OAR2_OA2MSK(n) (((n) & 0x7) << 8) 119 #define STM32F7_I2C_OAR2_OA2_7_MASK GENMASK(7, 1) 120 #define STM32F7_I2C_OAR2_OA2_7(n) (((n) & 0x7f) << 1) 121 #define STM32F7_I2C_OAR2_MASK (STM32F7_I2C_OAR2_OA2MSK_MASK \ 122 | STM32F7_I2C_OAR2_OA2_7_MASK \ 123 | STM32F7_I2C_OAR2_OA2EN) 124 125 /* STM32F7 I2C Interrupt Status */ 126 #define STM32F7_I2C_ISR_ADDCODE_MASK GENMASK(23, 17) 127 #define STM32F7_I2C_ISR_ADDCODE_GET(n) \ 128 (((n) & STM32F7_I2C_ISR_ADDCODE_MASK) >> 17) 129 #define STM32F7_I2C_ISR_DIR BIT(16) 130 #define STM32F7_I2C_ISR_BUSY BIT(15) 131 #define STM32F7_I2C_ISR_ALERT BIT(13) 132 #define STM32F7_I2C_ISR_PECERR BIT(11) 133 #define STM32F7_I2C_ISR_ARLO BIT(9) 134 #define STM32F7_I2C_ISR_BERR BIT(8) 135 #define STM32F7_I2C_ISR_TCR BIT(7) 136 #define STM32F7_I2C_ISR_TC BIT(6) 137 #define STM32F7_I2C_ISR_STOPF BIT(5) 138 #define STM32F7_I2C_ISR_NACKF BIT(4) 139 #define STM32F7_I2C_ISR_ADDR BIT(3) 140 #define STM32F7_I2C_ISR_RXNE BIT(2) 141 #define STM32F7_I2C_ISR_TXIS BIT(1) 142 #define STM32F7_I2C_ISR_TXE BIT(0) 143 144 /* STM32F7 I2C Interrupt Clear */ 145 #define STM32F7_I2C_ICR_ALERTCF BIT(13) 146 #define STM32F7_I2C_ICR_PECCF BIT(11) 147 #define STM32F7_I2C_ICR_ARLOCF BIT(9) 148 #define STM32F7_I2C_ICR_BERRCF BIT(8) 149 #define STM32F7_I2C_ICR_STOPCF BIT(5) 150 #define STM32F7_I2C_ICR_NACKCF BIT(4) 151 #define STM32F7_I2C_ICR_ADDRCF BIT(3) 152 153 /* STM32F7 I2C Timing */ 154 #define STM32F7_I2C_TIMINGR_PRESC(n) (((n) & 0xf) << 28) 155 #define STM32F7_I2C_TIMINGR_SCLDEL(n) (((n) & 0xf) << 20) 156 #define STM32F7_I2C_TIMINGR_SDADEL(n) (((n) & 0xf) << 16) 157 #define STM32F7_I2C_TIMINGR_SCLH(n) (((n) & 0xff) << 8) 158 #define STM32F7_I2C_TIMINGR_SCLL(n) ((n) & 0xff) 159 160 #define STM32F7_I2C_MAX_LEN 0xff 161 #define STM32F7_I2C_DMA_LEN_MIN 0x16 162 enum { 163 STM32F7_SLAVE_HOSTNOTIFY, 164 STM32F7_SLAVE_7_10_BITS_ADDR, 165 STM32F7_SLAVE_7_BITS_ADDR, 166 STM32F7_I2C_MAX_SLAVE 167 }; 168 169 #define STM32F7_I2C_DNF_DEFAULT 0 170 #define STM32F7_I2C_DNF_MAX 15 171 172 #define STM32F7_I2C_ANALOG_FILTER_DELAY_MIN 50 /* ns */ 173 #define STM32F7_I2C_ANALOG_FILTER_DELAY_MAX 260 /* ns */ 174 175 #define STM32F7_I2C_RISE_TIME_DEFAULT 25 /* ns */ 176 #define STM32F7_I2C_FALL_TIME_DEFAULT 10 /* ns */ 177 178 #define STM32F7_PRESC_MAX BIT(4) 179 #define STM32F7_SCLDEL_MAX BIT(4) 180 #define STM32F7_SDADEL_MAX BIT(4) 181 #define STM32F7_SCLH_MAX BIT(8) 182 #define STM32F7_SCLL_MAX BIT(8) 183 184 #define STM32F7_AUTOSUSPEND_DELAY (HZ / 100) 185 186 /** 187 * struct stm32f7_i2c_regs - i2c f7 registers backup 188 * @cr1: Control register 1 189 * @cr2: Control register 2 190 * @oar1: Own address 1 register 191 * @oar2: Own address 2 register 192 * @tmgr: Timing register 193 */ 194 struct stm32f7_i2c_regs { 195 u32 cr1; 196 u32 cr2; 197 u32 oar1; 198 u32 oar2; 199 u32 tmgr; 200 }; 201 202 /** 203 * struct stm32f7_i2c_spec - private i2c specification timing 204 * @rate: I2C bus speed (Hz) 205 * @fall_max: Max fall time of both SDA and SCL signals (ns) 206 * @rise_max: Max rise time of both SDA and SCL signals (ns) 207 * @hddat_min: Min data hold time (ns) 208 * @vddat_max: Max data valid time (ns) 209 * @sudat_min: Min data setup time (ns) 210 * @l_min: Min low period of the SCL clock (ns) 211 * @h_min: Min high period of the SCL clock (ns) 212 */ 213 struct stm32f7_i2c_spec { 214 u32 rate; 215 u32 fall_max; 216 u32 rise_max; 217 u32 hddat_min; 218 u32 vddat_max; 219 u32 sudat_min; 220 u32 l_min; 221 u32 h_min; 222 }; 223 224 /** 225 * struct stm32f7_i2c_setup - private I2C timing setup parameters 226 * @speed_freq: I2C speed frequency (Hz) 227 * @clock_src: I2C clock source frequency (Hz) 228 * @rise_time: Rise time (ns) 229 * @fall_time: Fall time (ns) 230 * @fmp_clr_offset: Fast Mode Plus clear register offset from set register 231 * @single_it_line: Only a single IT line is used for both events/errors 232 * @fmp_cr1_bit: Fast Mode Plus control is done via a bit in CR1 233 */ 234 struct stm32f7_i2c_setup { 235 u32 speed_freq; 236 u32 clock_src; 237 u32 rise_time; 238 u32 fall_time; 239 u32 fmp_clr_offset; 240 bool single_it_line; 241 bool fmp_cr1_bit; 242 }; 243 244 /** 245 * struct stm32f7_i2c_timings - private I2C output parameters 246 * @node: List entry 247 * @presc: Prescaler value 248 * @scldel: Data setup time 249 * @sdadel: Data hold time 250 * @sclh: SCL high period (master mode) 251 * @scll: SCL low period (master mode) 252 */ 253 struct stm32f7_i2c_timings { 254 struct list_head node; 255 u8 presc; 256 u8 scldel; 257 u8 sdadel; 258 u8 sclh; 259 u8 scll; 260 }; 261 262 /** 263 * struct stm32f7_i2c_msg - client specific data 264 * @addr: 8-bit or 10-bit slave addr, including r/w bit 265 * @count: number of bytes to be transferred 266 * @buf: data buffer 267 * @result: result of the transfer 268 * @stop: last I2C msg to be sent, i.e. STOP to be generated 269 * @smbus: boolean to know if the I2C IP is used in SMBus mode 270 * @size: type of SMBus protocol 271 * @read_write: direction of SMBus protocol 272 * SMBus block read and SMBus block write - block read process call protocols 273 * @smbus_buf: buffer to be used for SMBus protocol transfer. It will 274 * contain a maximum of 32 bytes of data + byte command + byte count + PEC 275 * This buffer has to be 32-bit aligned to be compliant with memory address 276 * register in DMA mode. 277 */ 278 struct stm32f7_i2c_msg { 279 u16 addr; 280 u32 count; 281 u8 *buf; 282 int result; 283 bool stop; 284 bool smbus; 285 int size; 286 char read_write; 287 u8 smbus_buf[I2C_SMBUS_BLOCK_MAX + 3] __aligned(4); 288 }; 289 290 /** 291 * struct stm32f7_i2c_alert - SMBus alert specific data 292 * @setup: platform data for the smbus_alert i2c client 293 * @ara: I2C slave device used to respond to the SMBus Alert with Alert 294 * Response Address 295 */ 296 struct stm32f7_i2c_alert { 297 struct i2c_smbus_alert_setup setup; 298 struct i2c_client *ara; 299 }; 300 301 /** 302 * struct stm32f7_i2c_dev - private data of the controller 303 * @adap: I2C adapter for this controller 304 * @dev: device for this controller 305 * @base: virtual memory area 306 * @complete: completion of I2C message 307 * @clk: hw i2c clock 308 * @bus_rate: I2C clock frequency of the controller 309 * @msg: Pointer to data to be written 310 * @msg_num: number of I2C messages to be executed 311 * @msg_id: message identifiant 312 * @f7_msg: customized i2c msg for driver usage 313 * @setup: I2C timing input setup 314 * @timing: I2C computed timings 315 * @slave: list of slave devices registered on the I2C bus 316 * @slave_running: slave device currently used 317 * @backup_regs: backup of i2c controller registers (for suspend/resume) 318 * @slave_dir: transfer direction for the current slave device 319 * @master_mode: boolean to know in which mode the I2C is running (master or 320 * slave) 321 * @dma: dma data 322 * @use_dma: boolean to know if dma is used in the current transfer 323 * @regmap: holds SYSCFG phandle for Fast Mode Plus bits 324 * @fmp_sreg: register address for setting Fast Mode Plus bits 325 * @fmp_creg: register address for clearing Fast Mode Plus bits 326 * @fmp_mask: mask for Fast Mode Plus bits in set register 327 * @wakeup_src: boolean to know if the device is a wakeup source 328 * @smbus_mode: states that the controller is configured in SMBus mode 329 * @host_notify_client: SMBus host-notify client 330 * @analog_filter: boolean to indicate enabling of the analog filter 331 * @dnf_dt: value of digital filter requested via dt 332 * @dnf: value of digital filter to apply 333 * @alert: SMBus alert specific data 334 * @atomic: boolean indicating that current transfer is atomic 335 */ 336 struct stm32f7_i2c_dev { 337 struct i2c_adapter adap; 338 struct device *dev; 339 void __iomem *base; 340 struct completion complete; 341 struct clk *clk; 342 unsigned int bus_rate; 343 struct i2c_msg *msg; 344 unsigned int msg_num; 345 unsigned int msg_id; 346 struct stm32f7_i2c_msg f7_msg; 347 struct stm32f7_i2c_setup setup; 348 struct stm32f7_i2c_timings timing; 349 struct i2c_client *slave[STM32F7_I2C_MAX_SLAVE]; 350 struct i2c_client *slave_running; 351 struct stm32f7_i2c_regs backup_regs; 352 u32 slave_dir; 353 bool master_mode; 354 struct stm32_i2c_dma *dma; 355 bool use_dma; 356 struct regmap *regmap; 357 u32 fmp_sreg; 358 u32 fmp_creg; 359 u32 fmp_mask; 360 bool wakeup_src; 361 bool smbus_mode; 362 struct i2c_client *host_notify_client; 363 bool analog_filter; 364 u32 dnf_dt; 365 u32 dnf; 366 struct stm32f7_i2c_alert *alert; 367 bool atomic; 368 }; 369 370 /* 371 * All these values are coming from I2C Specification, Version 6.0, 4th of 372 * April 2014. 373 * 374 * Table10. Characteristics of the SDA and SCL bus lines for Standard, Fast, 375 * and Fast-mode Plus I2C-bus devices 376 */ 377 static struct stm32f7_i2c_spec stm32f7_i2c_specs[] = { 378 { 379 .rate = I2C_MAX_STANDARD_MODE_FREQ, 380 .fall_max = 300, 381 .rise_max = 1000, 382 .hddat_min = 0, 383 .vddat_max = 3450, 384 .sudat_min = 250, 385 .l_min = 4700, 386 .h_min = 4000, 387 }, 388 { 389 .rate = I2C_MAX_FAST_MODE_FREQ, 390 .fall_max = 300, 391 .rise_max = 300, 392 .hddat_min = 0, 393 .vddat_max = 900, 394 .sudat_min = 100, 395 .l_min = 1300, 396 .h_min = 600, 397 }, 398 { 399 .rate = I2C_MAX_FAST_MODE_PLUS_FREQ, 400 .fall_max = 100, 401 .rise_max = 120, 402 .hddat_min = 0, 403 .vddat_max = 450, 404 .sudat_min = 50, 405 .l_min = 500, 406 .h_min = 260, 407 }, 408 }; 409 410 static const struct stm32f7_i2c_setup stm32f7_setup = { 411 .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT, 412 .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT, 413 }; 414 415 static const struct stm32f7_i2c_setup stm32mp15_setup = { 416 .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT, 417 .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT, 418 .fmp_clr_offset = 0x40, 419 }; 420 421 static const struct stm32f7_i2c_setup stm32mp13_setup = { 422 .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT, 423 .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT, 424 .fmp_clr_offset = 0x4, 425 }; 426 427 static const struct stm32f7_i2c_setup stm32mp25_setup = { 428 .rise_time = STM32F7_I2C_RISE_TIME_DEFAULT, 429 .fall_time = STM32F7_I2C_FALL_TIME_DEFAULT, 430 .single_it_line = true, 431 .fmp_cr1_bit = true, 432 }; 433 434 static inline void stm32f7_i2c_set_bits(void __iomem *reg, u32 mask) 435 { 436 writel_relaxed(readl_relaxed(reg) | mask, reg); 437 } 438 439 static inline void stm32f7_i2c_clr_bits(void __iomem *reg, u32 mask) 440 { 441 writel_relaxed(readl_relaxed(reg) & ~mask, reg); 442 } 443 444 static void stm32f7_i2c_disable_irq(struct stm32f7_i2c_dev *i2c_dev, u32 mask) 445 { 446 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, mask); 447 } 448 449 static struct stm32f7_i2c_spec *stm32f7_get_specs(u32 rate) 450 { 451 int i; 452 453 for (i = 0; i < ARRAY_SIZE(stm32f7_i2c_specs); i++) 454 if (rate <= stm32f7_i2c_specs[i].rate) 455 return &stm32f7_i2c_specs[i]; 456 457 return ERR_PTR(-EINVAL); 458 } 459 460 #define RATE_MIN(rate) ((rate) * 8 / 10) 461 static int stm32f7_i2c_compute_timing(struct stm32f7_i2c_dev *i2c_dev, 462 struct stm32f7_i2c_setup *setup, 463 struct stm32f7_i2c_timings *output) 464 { 465 struct stm32f7_i2c_spec *specs; 466 u32 p_prev = STM32F7_PRESC_MAX; 467 /* 468 * Truncate instead of rounding to closest: if the clock period is 469 * overestimated, the computed SCL timings will come out shorter on 470 * the wire, which can push the bus above the target rate and below 471 * the spec's tLOW/tHIGH minimums. 472 */ 473 u32 i2cclk = NSEC_PER_SEC / setup->clock_src; 474 u32 i2cbus = DIV_ROUND_CLOSEST(NSEC_PER_SEC, 475 setup->speed_freq); 476 u32 clk_error_prev = i2cbus; 477 u32 tsync; 478 u32 af_delay_min, af_delay_max; 479 u32 dnf_delay; 480 u32 clk_min, clk_max; 481 int sdadel_min, sdadel_max; 482 int scldel_min; 483 struct stm32f7_i2c_timings *v, *_v, *s; 484 struct list_head solutions; 485 u16 p, l, a, h; 486 int ret = 0; 487 488 specs = stm32f7_get_specs(setup->speed_freq); 489 if (specs == ERR_PTR(-EINVAL)) 490 return dev_err_probe(i2c_dev->dev, -EINVAL, "speed out of bound {%d}\n", 491 setup->speed_freq); 492 493 if ((setup->rise_time > specs->rise_max) || 494 (setup->fall_time > specs->fall_max)) 495 return dev_err_probe(i2c_dev->dev, -EINVAL, 496 "timings out of bound Rise{%d>%d}/Fall{%d>%d}\n", 497 setup->rise_time, specs->rise_max, 498 setup->fall_time, specs->fall_max); 499 500 i2c_dev->dnf = DIV_ROUND_CLOSEST(i2c_dev->dnf_dt, i2cclk); 501 if (i2c_dev->dnf > STM32F7_I2C_DNF_MAX) 502 return dev_err_probe(i2c_dev->dev, -EINVAL, 503 "DNF out of bound %d/%d\n", i2c_dev->dnf * i2cclk, 504 STM32F7_I2C_DNF_MAX * i2cclk); 505 506 /* Analog and Digital Filters */ 507 af_delay_min = 508 (i2c_dev->analog_filter ? 509 STM32F7_I2C_ANALOG_FILTER_DELAY_MIN : 0); 510 af_delay_max = 511 (i2c_dev->analog_filter ? 512 STM32F7_I2C_ANALOG_FILTER_DELAY_MAX : 0); 513 dnf_delay = i2c_dev->dnf * i2cclk; 514 515 sdadel_min = specs->hddat_min + setup->fall_time - 516 af_delay_min - (i2c_dev->dnf + 3) * i2cclk; 517 518 sdadel_max = specs->vddat_max - setup->rise_time - 519 af_delay_max - (i2c_dev->dnf + 4) * i2cclk; 520 521 scldel_min = setup->rise_time + specs->sudat_min; 522 523 if (sdadel_min < 0) 524 sdadel_min = 0; 525 if (sdadel_max < 0) 526 sdadel_max = 0; 527 528 dev_dbg(i2c_dev->dev, "SDADEL(min/max): %i/%i, SCLDEL(Min): %i\n", 529 sdadel_min, sdadel_max, scldel_min); 530 531 INIT_LIST_HEAD(&solutions); 532 /* Compute possible values for PRESC, SCLDEL and SDADEL */ 533 for (p = 0; p < STM32F7_PRESC_MAX; p++) { 534 for (l = 0; l < STM32F7_SCLDEL_MAX; l++) { 535 u32 scldel = (l + 1) * (p + 1) * i2cclk; 536 537 if (scldel < scldel_min) 538 continue; 539 540 for (a = 0; a < STM32F7_SDADEL_MAX; a++) { 541 u32 sdadel = (a * (p + 1) + 1) * i2cclk; 542 543 if (((sdadel >= sdadel_min) && 544 (sdadel <= sdadel_max)) && 545 (p != p_prev)) { 546 v = kmalloc_obj(*v); 547 if (!v) { 548 ret = -ENOMEM; 549 goto exit; 550 } 551 552 v->presc = p; 553 v->scldel = l; 554 v->sdadel = a; 555 p_prev = p; 556 557 list_add_tail(&v->node, 558 &solutions); 559 break; 560 } 561 } 562 563 if (p_prev == p) 564 break; 565 } 566 } 567 568 if (list_empty(&solutions)) { 569 ret = dev_err_probe(i2c_dev->dev, -EPERM, "no Prescaler solution\n"); 570 goto exit; 571 } 572 573 tsync = af_delay_min + dnf_delay + (2 * i2cclk); 574 s = NULL; 575 clk_max = NSEC_PER_SEC / RATE_MIN(setup->speed_freq); 576 clk_min = NSEC_PER_SEC / setup->speed_freq; 577 578 /* 579 * Among Prescaler possibilities discovered above figures out SCL Low 580 * and High Period. Provided: 581 * - SCL Low Period has to be higher than SCL Clock Low Period 582 * defined by I2C Specification. I2C Clock has to be lower than 583 * (SCL Low Period - Analog/Digital filters) / 4. 584 * - SCL High Period has to be lower than SCL Clock High Period 585 * defined by I2C Specification 586 * - I2C Clock has to be lower than SCL High Period 587 */ 588 list_for_each_entry(v, &solutions, node) { 589 u32 prescaler = (v->presc + 1) * i2cclk; 590 591 for (l = 0; l < STM32F7_SCLL_MAX; l++) { 592 u32 tscl_l = (l + 1) * prescaler + tsync; 593 594 if ((tscl_l < specs->l_min) || 595 (i2cclk >= 596 ((tscl_l - af_delay_min - dnf_delay) / 4))) { 597 continue; 598 } 599 600 for (h = 0; h < STM32F7_SCLH_MAX; h++) { 601 u32 tscl_h = (h + 1) * prescaler + tsync; 602 u32 tscl = tscl_l + tscl_h + 603 setup->rise_time + setup->fall_time; 604 605 if ((tscl >= clk_min) && (tscl <= clk_max) && 606 (tscl_h >= specs->h_min) && 607 (i2cclk < tscl_h)) { 608 int clk_error = tscl - i2cbus; 609 610 if (clk_error < 0) 611 clk_error = -clk_error; 612 613 if (clk_error < clk_error_prev) { 614 clk_error_prev = clk_error; 615 v->scll = l; 616 v->sclh = h; 617 s = v; 618 } 619 } 620 } 621 } 622 } 623 624 if (!s) { 625 ret = dev_err_probe(i2c_dev->dev, -EPERM, "no solution at all\n"); 626 goto exit; 627 } 628 629 output->presc = s->presc; 630 output->scldel = s->scldel; 631 output->sdadel = s->sdadel; 632 output->scll = s->scll; 633 output->sclh = s->sclh; 634 635 dev_dbg(i2c_dev->dev, 636 "Presc: %i, scldel: %i, sdadel: %i, scll: %i, sclh: %i\n", 637 output->presc, 638 output->scldel, output->sdadel, 639 output->scll, output->sclh); 640 641 exit: 642 /* Release list and memory */ 643 list_for_each_entry_safe(v, _v, &solutions, node) { 644 list_del(&v->node); 645 kfree(v); 646 } 647 648 return ret; 649 } 650 651 static u32 stm32f7_get_lower_rate(u32 rate) 652 { 653 int i = ARRAY_SIZE(stm32f7_i2c_specs); 654 655 while (--i) 656 if (stm32f7_i2c_specs[i].rate < rate) 657 break; 658 659 return stm32f7_i2c_specs[i].rate; 660 } 661 662 static int stm32f7_i2c_setup_timing(struct stm32f7_i2c_dev *i2c_dev, 663 struct stm32f7_i2c_setup *setup) 664 { 665 struct i2c_timings timings, *t = &timings; 666 int ret = 0; 667 668 t->bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ; 669 t->scl_rise_ns = i2c_dev->setup.rise_time; 670 t->scl_fall_ns = i2c_dev->setup.fall_time; 671 672 i2c_parse_fw_timings(i2c_dev->dev, t, false); 673 674 if (t->bus_freq_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) 675 return dev_err_probe(i2c_dev->dev, -EINVAL, "Invalid bus speed (%i>%i)\n", 676 t->bus_freq_hz, I2C_MAX_FAST_MODE_PLUS_FREQ); 677 678 setup->speed_freq = t->bus_freq_hz; 679 i2c_dev->setup.rise_time = t->scl_rise_ns; 680 i2c_dev->setup.fall_time = t->scl_fall_ns; 681 i2c_dev->dnf_dt = t->digital_filter_width_ns; 682 setup->clock_src = clk_get_rate(i2c_dev->clk); 683 684 if (!setup->clock_src) 685 return dev_err_probe(i2c_dev->dev, -EINVAL, "clock rate is 0\n"); 686 687 if (!of_property_read_bool(i2c_dev->dev->of_node, "i2c-digital-filter")) 688 i2c_dev->dnf_dt = STM32F7_I2C_DNF_DEFAULT; 689 690 i2c_dev->analog_filter = of_property_read_bool(i2c_dev->dev->of_node, 691 "i2c-analog-filter"); 692 693 do { 694 ret = stm32f7_i2c_compute_timing(i2c_dev, setup, 695 &i2c_dev->timing); 696 if (ret) { 697 dev_err_probe(i2c_dev->dev, ret, 698 "failed to compute I2C timings.\n"); 699 if (setup->speed_freq <= I2C_MAX_STANDARD_MODE_FREQ) 700 break; 701 setup->speed_freq = 702 stm32f7_get_lower_rate(setup->speed_freq); 703 dev_warn(i2c_dev->dev, 704 "downgrade I2C Speed Freq to (%i)\n", 705 setup->speed_freq); 706 } 707 } while (ret); 708 709 if (ret) 710 return dev_err_probe(i2c_dev->dev, ret, "Impossible to compute I2C timings.\n"); 711 712 dev_dbg(i2c_dev->dev, "I2C Speed(%i), Clk Source(%i)\n", 713 setup->speed_freq, setup->clock_src); 714 dev_dbg(i2c_dev->dev, "I2C Rise(%i) and Fall(%i) Time\n", 715 setup->rise_time, setup->fall_time); 716 dev_dbg(i2c_dev->dev, "I2C Analog Filter(%s), DNF(%i)\n", 717 str_on_off(i2c_dev->analog_filter), i2c_dev->dnf); 718 719 i2c_dev->bus_rate = setup->speed_freq; 720 721 return 0; 722 } 723 724 static void stm32f7_i2c_disable_dma_req(struct stm32f7_i2c_dev *i2c_dev) 725 { 726 void __iomem *base = i2c_dev->base; 727 u32 mask = STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN; 728 729 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask); 730 } 731 732 static void stm32f7_i2c_dma_callback(void *arg) 733 { 734 struct stm32f7_i2c_dev *i2c_dev = arg; 735 struct stm32_i2c_dma *dma = i2c_dev->dma; 736 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 737 738 stm32f7_i2c_disable_dma_req(i2c_dev); 739 dmaengine_terminate_async(dma->chan_using); 740 dma_unmap_single(i2c_dev->dev, dma->dma_buf, dma->dma_len, 741 dma->dma_data_dir); 742 if (!f7_msg->smbus) 743 i2c_put_dma_safe_msg_buf(f7_msg->buf, i2c_dev->msg, true); 744 complete(&dma->dma_complete); 745 } 746 747 static void stm32f7_i2c_hw_config(struct stm32f7_i2c_dev *i2c_dev) 748 { 749 struct stm32f7_i2c_timings *t = &i2c_dev->timing; 750 u32 timing = 0; 751 752 /* Timing settings */ 753 timing |= STM32F7_I2C_TIMINGR_PRESC(t->presc); 754 timing |= STM32F7_I2C_TIMINGR_SCLDEL(t->scldel); 755 timing |= STM32F7_I2C_TIMINGR_SDADEL(t->sdadel); 756 timing |= STM32F7_I2C_TIMINGR_SCLH(t->sclh); 757 timing |= STM32F7_I2C_TIMINGR_SCLL(t->scll); 758 writel_relaxed(timing, i2c_dev->base + STM32F7_I2C_TIMINGR); 759 760 /* Configure the Analog Filter */ 761 if (i2c_dev->analog_filter) 762 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, 763 STM32F7_I2C_CR1_ANFOFF); 764 else 765 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, 766 STM32F7_I2C_CR1_ANFOFF); 767 768 /* Program the Digital Filter */ 769 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, 770 STM32F7_I2C_CR1_DNF_MASK); 771 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, 772 STM32F7_I2C_CR1_DNF(i2c_dev->dnf)); 773 774 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, 775 STM32F7_I2C_CR1_PE); 776 } 777 778 static void stm32f7_i2c_write_tx_data(struct stm32f7_i2c_dev *i2c_dev) 779 { 780 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 781 void __iomem *base = i2c_dev->base; 782 783 if (f7_msg->count) { 784 writeb_relaxed(*f7_msg->buf++, base + STM32F7_I2C_TXDR); 785 f7_msg->count--; 786 } 787 } 788 789 static void stm32f7_i2c_read_rx_data(struct stm32f7_i2c_dev *i2c_dev) 790 { 791 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 792 void __iomem *base = i2c_dev->base; 793 794 if (f7_msg->count) { 795 *f7_msg->buf++ = readb_relaxed(base + STM32F7_I2C_RXDR); 796 f7_msg->count--; 797 } else { 798 /* Flush RX buffer has no data is expected */ 799 readb_relaxed(base + STM32F7_I2C_RXDR); 800 } 801 } 802 803 static void stm32f7_i2c_reload(struct stm32f7_i2c_dev *i2c_dev) 804 { 805 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 806 u32 cr2; 807 808 if (i2c_dev->use_dma) 809 f7_msg->count -= STM32F7_I2C_MAX_LEN; 810 811 cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2); 812 813 cr2 &= ~STM32F7_I2C_CR2_NBYTES_MASK; 814 if (f7_msg->count > STM32F7_I2C_MAX_LEN) { 815 cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN); 816 } else { 817 cr2 &= ~STM32F7_I2C_CR2_RELOAD; 818 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count); 819 } 820 821 writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2); 822 } 823 824 static void stm32f7_i2c_smbus_reload(struct stm32f7_i2c_dev *i2c_dev) 825 { 826 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 827 u32 cr2; 828 u8 *val; 829 830 /* 831 * For I2C_SMBUS_BLOCK_DATA && I2C_SMBUS_BLOCK_PROC_CALL, the first 832 * data received inform us how many data will follow. 833 */ 834 stm32f7_i2c_read_rx_data(i2c_dev); 835 836 /* 837 * Update NBYTES with the value read to continue the transfer 838 */ 839 val = f7_msg->buf - sizeof(u8); 840 f7_msg->count = *val; 841 cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2); 842 cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD); 843 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count); 844 writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2); 845 } 846 847 static void stm32f7_i2c_release_bus(struct i2c_adapter *i2c_adap) 848 { 849 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap); 850 851 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, 852 STM32F7_I2C_CR1_PE); 853 854 stm32f7_i2c_hw_config(i2c_dev); 855 } 856 857 static int stm32f7_i2c_wait_free_bus(struct stm32f7_i2c_dev *i2c_dev) 858 { 859 u32 status; 860 int ret; 861 862 ret = readl_relaxed_poll_timeout(i2c_dev->base + STM32F7_I2C_ISR, 863 status, 864 !(status & STM32F7_I2C_ISR_BUSY), 865 10, 1000); 866 if (!ret) 867 return 0; 868 869 stm32f7_i2c_release_bus(&i2c_dev->adap); 870 871 return -EBUSY; 872 } 873 874 static void stm32f7_i2c_xfer_msg(struct stm32f7_i2c_dev *i2c_dev, 875 struct i2c_msg *msg) 876 { 877 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 878 void __iomem *base = i2c_dev->base; 879 u8 *dma_buf; 880 u32 cr1, cr2; 881 int ret; 882 883 f7_msg->addr = msg->addr; 884 f7_msg->buf = msg->buf; 885 f7_msg->count = msg->len; 886 f7_msg->result = 0; 887 f7_msg->stop = (i2c_dev->msg_id >= i2c_dev->msg_num - 1); 888 889 cr1 = readl_relaxed(base + STM32F7_I2C_CR1); 890 cr2 = readl_relaxed(base + STM32F7_I2C_CR2); 891 892 /* Set transfer direction */ 893 cr2 &= ~STM32F7_I2C_CR2_RD_WRN; 894 if (msg->flags & I2C_M_RD) 895 cr2 |= STM32F7_I2C_CR2_RD_WRN; 896 897 /* Set slave address */ 898 cr2 &= ~(STM32F7_I2C_CR2_HEAD10R | STM32F7_I2C_CR2_ADD10); 899 if (msg->flags & I2C_M_TEN) { 900 cr2 &= ~STM32F7_I2C_CR2_SADD10_MASK; 901 cr2 |= STM32F7_I2C_CR2_SADD10(f7_msg->addr); 902 cr2 |= STM32F7_I2C_CR2_ADD10; 903 } else { 904 cr2 &= ~STM32F7_I2C_CR2_SADD7_MASK; 905 cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr); 906 } 907 908 /* Set nb bytes to transfer and reload if needed */ 909 cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD); 910 if (f7_msg->count > STM32F7_I2C_MAX_LEN) { 911 cr2 |= STM32F7_I2C_CR2_NBYTES(STM32F7_I2C_MAX_LEN); 912 cr2 |= STM32F7_I2C_CR2_RELOAD; 913 } else { 914 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count); 915 } 916 917 /* Enable NACK, STOP, error and transfer complete interrupts */ 918 cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE | 919 STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE; 920 921 /* Clear DMA req and TX/RX interrupt */ 922 cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE | 923 STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN); 924 925 /* Configure DMA or enable RX/TX interrupt */ 926 i2c_dev->use_dma = false; 927 if (i2c_dev->dma && !i2c_dev->atomic) { 928 dma_buf = i2c_get_dma_safe_msg_buf(msg, STM32F7_I2C_DMA_LEN_MIN); 929 if (dma_buf) { 930 f7_msg->buf = dma_buf; 931 ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma, 932 msg->flags & I2C_M_RD, 933 f7_msg->count, f7_msg->buf, 934 stm32f7_i2c_dma_callback, 935 i2c_dev); 936 if (ret) { 937 dev_warn(i2c_dev->dev, "can't use DMA\n"); 938 i2c_put_dma_safe_msg_buf(f7_msg->buf, msg, false); 939 f7_msg->buf = msg->buf; 940 } else { 941 i2c_dev->use_dma = true; 942 } 943 } 944 } 945 946 if (!i2c_dev->use_dma) { 947 if (msg->flags & I2C_M_RD) 948 cr1 |= STM32F7_I2C_CR1_RXIE; 949 else 950 cr1 |= STM32F7_I2C_CR1_TXIE; 951 } else { 952 if (msg->flags & I2C_M_RD) 953 cr1 |= STM32F7_I2C_CR1_RXDMAEN; 954 else 955 cr1 |= STM32F7_I2C_CR1_TXDMAEN; 956 } 957 958 if (i2c_dev->atomic) 959 cr1 &= ~STM32F7_I2C_ALL_IRQ_MASK; /* Disable all interrupts */ 960 961 /* Configure Start/Repeated Start */ 962 cr2 |= STM32F7_I2C_CR2_START; 963 964 i2c_dev->master_mode = true; 965 966 /* Write configurations registers */ 967 writel_relaxed(cr1, base + STM32F7_I2C_CR1); 968 writel_relaxed(cr2, base + STM32F7_I2C_CR2); 969 } 970 971 static int stm32f7_i2c_smbus_xfer_msg(struct stm32f7_i2c_dev *i2c_dev, 972 unsigned short flags, u8 command, 973 union i2c_smbus_data *data) 974 { 975 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 976 struct device *dev = i2c_dev->dev; 977 void __iomem *base = i2c_dev->base; 978 u32 cr1, cr2; 979 int i, ret; 980 981 f7_msg->result = 0; 982 reinit_completion(&i2c_dev->complete); 983 984 cr2 = readl_relaxed(base + STM32F7_I2C_CR2); 985 cr1 = readl_relaxed(base + STM32F7_I2C_CR1); 986 987 /* Set transfer direction */ 988 cr2 &= ~STM32F7_I2C_CR2_RD_WRN; 989 if (f7_msg->read_write) 990 cr2 |= STM32F7_I2C_CR2_RD_WRN; 991 992 /* Set slave address */ 993 cr2 &= ~(STM32F7_I2C_CR2_ADD10 | STM32F7_I2C_CR2_SADD7_MASK); 994 cr2 |= STM32F7_I2C_CR2_SADD7(f7_msg->addr); 995 996 f7_msg->smbus_buf[0] = command; 997 switch (f7_msg->size) { 998 case I2C_SMBUS_QUICK: 999 f7_msg->stop = true; 1000 f7_msg->count = 0; 1001 break; 1002 case I2C_SMBUS_BYTE: 1003 f7_msg->stop = true; 1004 f7_msg->count = 1; 1005 break; 1006 case I2C_SMBUS_BYTE_DATA: 1007 if (f7_msg->read_write) { 1008 f7_msg->stop = false; 1009 f7_msg->count = 1; 1010 cr2 &= ~STM32F7_I2C_CR2_RD_WRN; 1011 } else { 1012 f7_msg->stop = true; 1013 f7_msg->count = 2; 1014 f7_msg->smbus_buf[1] = data->byte; 1015 } 1016 break; 1017 case I2C_SMBUS_WORD_DATA: 1018 if (f7_msg->read_write) { 1019 f7_msg->stop = false; 1020 f7_msg->count = 1; 1021 cr2 &= ~STM32F7_I2C_CR2_RD_WRN; 1022 } else { 1023 f7_msg->stop = true; 1024 f7_msg->count = 3; 1025 f7_msg->smbus_buf[1] = data->word & 0xff; 1026 f7_msg->smbus_buf[2] = data->word >> 8; 1027 } 1028 break; 1029 case I2C_SMBUS_BLOCK_DATA: 1030 if (f7_msg->read_write) { 1031 f7_msg->stop = false; 1032 f7_msg->count = 1; 1033 cr2 &= ~STM32F7_I2C_CR2_RD_WRN; 1034 } else { 1035 f7_msg->stop = true; 1036 if (data->block[0] > I2C_SMBUS_BLOCK_MAX || 1037 !data->block[0]) { 1038 dev_err(dev, "Invalid block write size %d\n", 1039 data->block[0]); 1040 return -EINVAL; 1041 } 1042 f7_msg->count = data->block[0] + 2; 1043 for (i = 1; i < f7_msg->count; i++) 1044 f7_msg->smbus_buf[i] = data->block[i - 1]; 1045 } 1046 break; 1047 case I2C_SMBUS_PROC_CALL: 1048 f7_msg->stop = false; 1049 f7_msg->count = 3; 1050 f7_msg->smbus_buf[1] = data->word & 0xff; 1051 f7_msg->smbus_buf[2] = data->word >> 8; 1052 cr2 &= ~STM32F7_I2C_CR2_RD_WRN; 1053 f7_msg->read_write = I2C_SMBUS_READ; 1054 break; 1055 case I2C_SMBUS_BLOCK_PROC_CALL: 1056 f7_msg->stop = false; 1057 if (data->block[0] > I2C_SMBUS_BLOCK_MAX - 1) { 1058 dev_err(dev, "Invalid block write size %d\n", 1059 data->block[0]); 1060 return -EINVAL; 1061 } 1062 f7_msg->count = data->block[0] + 2; 1063 for (i = 1; i < f7_msg->count; i++) 1064 f7_msg->smbus_buf[i] = data->block[i - 1]; 1065 cr2 &= ~STM32F7_I2C_CR2_RD_WRN; 1066 f7_msg->read_write = I2C_SMBUS_READ; 1067 break; 1068 case I2C_SMBUS_I2C_BLOCK_DATA: 1069 /* Rely on emulated i2c transfer (through master_xfer) */ 1070 return -EOPNOTSUPP; 1071 default: 1072 dev_err(dev, "Unsupported smbus protocol %d\n", f7_msg->size); 1073 return -EOPNOTSUPP; 1074 } 1075 1076 f7_msg->buf = f7_msg->smbus_buf; 1077 1078 /* Configure PEC */ 1079 if ((flags & I2C_CLIENT_PEC) && f7_msg->size != I2C_SMBUS_QUICK) { 1080 cr1 |= STM32F7_I2C_CR1_PECEN; 1081 if (!f7_msg->read_write) { 1082 cr2 |= STM32F7_I2C_CR2_PECBYTE; 1083 f7_msg->count++; 1084 } 1085 } else { 1086 cr1 &= ~STM32F7_I2C_CR1_PECEN; 1087 cr2 &= ~STM32F7_I2C_CR2_PECBYTE; 1088 } 1089 1090 /* Set number of bytes to be transferred */ 1091 cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK | STM32F7_I2C_CR2_RELOAD); 1092 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count); 1093 1094 /* Enable NACK, STOP, error and transfer complete interrupts */ 1095 cr1 |= STM32F7_I2C_CR1_ERRIE | STM32F7_I2C_CR1_TCIE | 1096 STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE; 1097 1098 /* Clear DMA req and TX/RX interrupt */ 1099 cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE | 1100 STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN); 1101 1102 /* Configure DMA or enable RX/TX interrupt */ 1103 i2c_dev->use_dma = false; 1104 if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN) { 1105 ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma, 1106 cr2 & STM32F7_I2C_CR2_RD_WRN, 1107 f7_msg->count, f7_msg->buf, 1108 stm32f7_i2c_dma_callback, 1109 i2c_dev); 1110 if (!ret) 1111 i2c_dev->use_dma = true; 1112 else 1113 dev_warn(i2c_dev->dev, "can't use DMA\n"); 1114 } 1115 1116 if (!i2c_dev->use_dma) { 1117 if (cr2 & STM32F7_I2C_CR2_RD_WRN) 1118 cr1 |= STM32F7_I2C_CR1_RXIE; 1119 else 1120 cr1 |= STM32F7_I2C_CR1_TXIE; 1121 } else { 1122 if (cr2 & STM32F7_I2C_CR2_RD_WRN) 1123 cr1 |= STM32F7_I2C_CR1_RXDMAEN; 1124 else 1125 cr1 |= STM32F7_I2C_CR1_TXDMAEN; 1126 } 1127 1128 /* Set Start bit */ 1129 cr2 |= STM32F7_I2C_CR2_START; 1130 1131 i2c_dev->master_mode = true; 1132 1133 /* Write configurations registers */ 1134 writel_relaxed(cr1, base + STM32F7_I2C_CR1); 1135 writel_relaxed(cr2, base + STM32F7_I2C_CR2); 1136 1137 return 0; 1138 } 1139 1140 static void stm32f7_i2c_smbus_rep_start(struct stm32f7_i2c_dev *i2c_dev) 1141 { 1142 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 1143 void __iomem *base = i2c_dev->base; 1144 u32 cr1, cr2; 1145 int ret; 1146 1147 cr2 = readl_relaxed(base + STM32F7_I2C_CR2); 1148 cr1 = readl_relaxed(base + STM32F7_I2C_CR1); 1149 1150 /* Set transfer direction */ 1151 cr2 |= STM32F7_I2C_CR2_RD_WRN; 1152 1153 switch (f7_msg->size) { 1154 case I2C_SMBUS_BYTE_DATA: 1155 f7_msg->count = 1; 1156 break; 1157 case I2C_SMBUS_WORD_DATA: 1158 case I2C_SMBUS_PROC_CALL: 1159 f7_msg->count = 2; 1160 break; 1161 case I2C_SMBUS_BLOCK_DATA: 1162 case I2C_SMBUS_BLOCK_PROC_CALL: 1163 f7_msg->count = 1; 1164 cr2 |= STM32F7_I2C_CR2_RELOAD; 1165 break; 1166 } 1167 1168 f7_msg->buf = f7_msg->smbus_buf; 1169 f7_msg->stop = true; 1170 1171 /* Add one byte for PEC if needed */ 1172 if (cr1 & STM32F7_I2C_CR1_PECEN) { 1173 cr2 |= STM32F7_I2C_CR2_PECBYTE; 1174 f7_msg->count++; 1175 } 1176 1177 /* Set number of bytes to be transferred */ 1178 cr2 &= ~(STM32F7_I2C_CR2_NBYTES_MASK); 1179 cr2 |= STM32F7_I2C_CR2_NBYTES(f7_msg->count); 1180 1181 /* 1182 * Configure RX/TX interrupt: 1183 */ 1184 cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE); 1185 cr1 |= STM32F7_I2C_CR1_RXIE; 1186 1187 /* 1188 * Configure DMA or enable RX/TX interrupt: 1189 * For I2C_SMBUS_BLOCK_DATA and I2C_SMBUS_BLOCK_PROC_CALL we don't use 1190 * dma as we don't know in advance how many data will be received 1191 */ 1192 cr1 &= ~(STM32F7_I2C_CR1_RXIE | STM32F7_I2C_CR1_TXIE | 1193 STM32F7_I2C_CR1_RXDMAEN | STM32F7_I2C_CR1_TXDMAEN); 1194 1195 i2c_dev->use_dma = false; 1196 if (i2c_dev->dma && f7_msg->count >= STM32F7_I2C_DMA_LEN_MIN && 1197 f7_msg->size != I2C_SMBUS_BLOCK_DATA && 1198 f7_msg->size != I2C_SMBUS_BLOCK_PROC_CALL) { 1199 ret = stm32_i2c_prep_dma_xfer(i2c_dev->dev, i2c_dev->dma, 1200 cr2 & STM32F7_I2C_CR2_RD_WRN, 1201 f7_msg->count, f7_msg->buf, 1202 stm32f7_i2c_dma_callback, 1203 i2c_dev); 1204 1205 if (!ret) 1206 i2c_dev->use_dma = true; 1207 else 1208 dev_warn(i2c_dev->dev, "can't use DMA\n"); 1209 } 1210 1211 if (!i2c_dev->use_dma) 1212 cr1 |= STM32F7_I2C_CR1_RXIE; 1213 else 1214 cr1 |= STM32F7_I2C_CR1_RXDMAEN; 1215 1216 /* Configure Repeated Start */ 1217 cr2 |= STM32F7_I2C_CR2_START; 1218 1219 /* Write configurations registers */ 1220 writel_relaxed(cr1, base + STM32F7_I2C_CR1); 1221 writel_relaxed(cr2, base + STM32F7_I2C_CR2); 1222 } 1223 1224 static int stm32f7_i2c_smbus_check_pec(struct stm32f7_i2c_dev *i2c_dev) 1225 { 1226 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 1227 u8 count, internal_pec, received_pec; 1228 1229 internal_pec = readl_relaxed(i2c_dev->base + STM32F7_I2C_PECR); 1230 1231 switch (f7_msg->size) { 1232 case I2C_SMBUS_BYTE: 1233 case I2C_SMBUS_BYTE_DATA: 1234 received_pec = f7_msg->smbus_buf[1]; 1235 break; 1236 case I2C_SMBUS_WORD_DATA: 1237 case I2C_SMBUS_PROC_CALL: 1238 received_pec = f7_msg->smbus_buf[2]; 1239 break; 1240 case I2C_SMBUS_BLOCK_DATA: 1241 case I2C_SMBUS_BLOCK_PROC_CALL: 1242 count = f7_msg->smbus_buf[0]; 1243 received_pec = f7_msg->smbus_buf[count]; 1244 break; 1245 default: 1246 dev_err(i2c_dev->dev, "Unsupported smbus protocol for PEC\n"); 1247 return -EINVAL; 1248 } 1249 1250 if (internal_pec != received_pec) { 1251 dev_err(i2c_dev->dev, "Bad PEC 0x%02x vs. 0x%02x\n", 1252 internal_pec, received_pec); 1253 return -EBADMSG; 1254 } 1255 1256 return 0; 1257 } 1258 1259 static bool stm32f7_i2c_is_addr_match(struct i2c_client *slave, u32 addcode) 1260 { 1261 u32 addr; 1262 1263 if (!slave) 1264 return false; 1265 1266 if (slave->flags & I2C_CLIENT_TEN) { 1267 /* 1268 * For 10-bit addr, addcode = 11110XY with 1269 * X = Bit 9 of slave address 1270 * Y = Bit 8 of slave address 1271 */ 1272 addr = slave->addr >> 8; 1273 addr |= 0x78; 1274 if (addr == addcode) 1275 return true; 1276 } else { 1277 addr = slave->addr & 0x7f; 1278 if (addr == addcode) 1279 return true; 1280 } 1281 1282 return false; 1283 } 1284 1285 static void stm32f7_i2c_slave_start(struct stm32f7_i2c_dev *i2c_dev) 1286 { 1287 struct i2c_client *slave = i2c_dev->slave_running; 1288 void __iomem *base = i2c_dev->base; 1289 u32 mask; 1290 u8 value = 0; 1291 1292 if (i2c_dev->slave_dir) { 1293 /* Notify i2c slave that new read transfer is starting */ 1294 i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value); 1295 1296 /* 1297 * Disable slave TX config in case of I2C combined message 1298 * (I2C Write followed by I2C Read) 1299 */ 1300 mask = STM32F7_I2C_CR2_RELOAD; 1301 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, mask); 1302 mask = STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE | 1303 STM32F7_I2C_CR1_TCIE; 1304 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask); 1305 1306 /* Enable TX empty, STOP, NACK interrupts */ 1307 mask = STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE | 1308 STM32F7_I2C_CR1_TXIE; 1309 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask); 1310 1311 /* Write 1st data byte */ 1312 writel_relaxed(value, base + STM32F7_I2C_TXDR); 1313 } else { 1314 /* Notify i2c slave that new write transfer is starting */ 1315 i2c_slave_event(slave, I2C_SLAVE_WRITE_REQUESTED, &value); 1316 1317 /* Set reload mode to be able to ACK/NACK each received byte */ 1318 mask = STM32F7_I2C_CR2_RELOAD; 1319 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask); 1320 1321 /* 1322 * Set STOP, NACK, RX empty and transfer complete interrupts.* 1323 * Set Slave Byte Control to be able to ACK/NACK each data 1324 * byte received 1325 */ 1326 mask = STM32F7_I2C_CR1_STOPIE | STM32F7_I2C_CR1_NACKIE | 1327 STM32F7_I2C_CR1_SBC | STM32F7_I2C_CR1_RXIE | 1328 STM32F7_I2C_CR1_TCIE; 1329 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask); 1330 } 1331 } 1332 1333 static void stm32f7_i2c_slave_addr(struct stm32f7_i2c_dev *i2c_dev) 1334 { 1335 void __iomem *base = i2c_dev->base; 1336 u32 isr, addcode, dir, mask; 1337 int i; 1338 1339 isr = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); 1340 addcode = STM32F7_I2C_ISR_ADDCODE_GET(isr); 1341 dir = isr & STM32F7_I2C_ISR_DIR; 1342 1343 for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) { 1344 if (stm32f7_i2c_is_addr_match(i2c_dev->slave[i], addcode)) { 1345 i2c_dev->slave_running = i2c_dev->slave[i]; 1346 i2c_dev->slave_dir = dir; 1347 1348 /* Start I2C slave processing */ 1349 stm32f7_i2c_slave_start(i2c_dev); 1350 1351 /* Clear ADDR flag */ 1352 mask = STM32F7_I2C_ICR_ADDRCF; 1353 writel_relaxed(mask, base + STM32F7_I2C_ICR); 1354 break; 1355 } 1356 } 1357 } 1358 1359 static int stm32f7_i2c_get_slave_id(struct stm32f7_i2c_dev *i2c_dev, 1360 struct i2c_client *slave, int *id) 1361 { 1362 int i; 1363 1364 for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) { 1365 if (i2c_dev->slave[i] == slave) { 1366 *id = i; 1367 return 0; 1368 } 1369 } 1370 1371 dev_err(i2c_dev->dev, "Slave 0x%x not registered\n", slave->addr); 1372 1373 return -ENODEV; 1374 } 1375 1376 static int stm32f7_i2c_get_free_slave_id(struct stm32f7_i2c_dev *i2c_dev, 1377 struct i2c_client *slave, int *id) 1378 { 1379 struct device *dev = i2c_dev->dev; 1380 int i; 1381 1382 /* 1383 * slave[STM32F7_SLAVE_HOSTNOTIFY] support only SMBus Host address (0x8) 1384 * slave[STM32F7_SLAVE_7_10_BITS_ADDR] supports 7-bit and 10-bit slave address 1385 * slave[STM32F7_SLAVE_7_BITS_ADDR] supports 7-bit slave address only 1386 */ 1387 if (i2c_dev->smbus_mode && (slave->addr == 0x08)) { 1388 if (i2c_dev->slave[STM32F7_SLAVE_HOSTNOTIFY]) 1389 goto fail; 1390 *id = STM32F7_SLAVE_HOSTNOTIFY; 1391 return 0; 1392 } 1393 1394 for (i = STM32F7_I2C_MAX_SLAVE - 1; i > STM32F7_SLAVE_HOSTNOTIFY; i--) { 1395 if ((i == STM32F7_SLAVE_7_BITS_ADDR) && 1396 (slave->flags & I2C_CLIENT_TEN)) 1397 continue; 1398 if (!i2c_dev->slave[i]) { 1399 *id = i; 1400 return 0; 1401 } 1402 } 1403 1404 fail: 1405 dev_err(dev, "Slave 0x%x could not be registered\n", slave->addr); 1406 1407 return -EINVAL; 1408 } 1409 1410 static bool stm32f7_i2c_is_slave_registered(struct stm32f7_i2c_dev *i2c_dev) 1411 { 1412 int i; 1413 1414 for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) { 1415 if (i2c_dev->slave[i]) 1416 return true; 1417 } 1418 1419 return false; 1420 } 1421 1422 static bool stm32f7_i2c_is_slave_busy(struct stm32f7_i2c_dev *i2c_dev) 1423 { 1424 int i, busy; 1425 1426 busy = 0; 1427 for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) { 1428 if (i2c_dev->slave[i]) 1429 busy++; 1430 } 1431 1432 return i == busy; 1433 } 1434 1435 static irqreturn_t stm32f7_i2c_slave_isr_event(struct stm32f7_i2c_dev *i2c_dev, u32 status) 1436 { 1437 void __iomem *base = i2c_dev->base; 1438 u32 cr2, mask; 1439 u8 val; 1440 int ret; 1441 1442 /* Slave transmitter mode */ 1443 if (status & STM32F7_I2C_ISR_TXIS) { 1444 i2c_slave_event(i2c_dev->slave_running, 1445 I2C_SLAVE_READ_PROCESSED, 1446 &val); 1447 1448 /* Write data byte */ 1449 writel_relaxed(val, base + STM32F7_I2C_TXDR); 1450 } 1451 1452 /* Transfer Complete Reload for Slave receiver mode */ 1453 if (status & STM32F7_I2C_ISR_TCR || status & STM32F7_I2C_ISR_RXNE) { 1454 /* 1455 * Read data byte then set NBYTES to receive next byte or NACK 1456 * the current received byte 1457 */ 1458 val = readb_relaxed(i2c_dev->base + STM32F7_I2C_RXDR); 1459 ret = i2c_slave_event(i2c_dev->slave_running, 1460 I2C_SLAVE_WRITE_RECEIVED, 1461 &val); 1462 if (!ret) { 1463 cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2); 1464 cr2 |= STM32F7_I2C_CR2_NBYTES(1); 1465 writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2); 1466 } else { 1467 mask = STM32F7_I2C_CR2_NACK; 1468 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask); 1469 } 1470 } 1471 1472 /* NACK received */ 1473 if (status & STM32F7_I2C_ISR_NACKF) { 1474 dev_dbg(i2c_dev->dev, "<%s>: Receive NACK\n", __func__); 1475 writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR); 1476 } 1477 1478 /* STOP received */ 1479 if (status & STM32F7_I2C_ISR_STOPF) { 1480 /* Disable interrupts */ 1481 stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_XFER_IRQ_MASK); 1482 1483 if (i2c_dev->slave_dir) { 1484 /* 1485 * Flush TX buffer in order to not used the byte in 1486 * TXDR for the next transfer 1487 */ 1488 mask = STM32F7_I2C_ISR_TXE; 1489 stm32f7_i2c_set_bits(base + STM32F7_I2C_ISR, mask); 1490 } 1491 1492 /* Clear STOP flag */ 1493 writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR); 1494 1495 /* Notify i2c slave that a STOP flag has been detected */ 1496 i2c_slave_event(i2c_dev->slave_running, I2C_SLAVE_STOP, &val); 1497 1498 i2c_dev->slave_running = NULL; 1499 } 1500 1501 /* Address match received */ 1502 if (status & STM32F7_I2C_ISR_ADDR) 1503 stm32f7_i2c_slave_addr(i2c_dev); 1504 1505 return IRQ_HANDLED; 1506 } 1507 1508 static irqreturn_t stm32f7_i2c_handle_isr_errs(struct stm32f7_i2c_dev *i2c_dev, u32 status) 1509 { 1510 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 1511 u16 addr = f7_msg->addr; 1512 void __iomem *base = i2c_dev->base; 1513 struct device *dev = i2c_dev->dev; 1514 1515 /* Bus error */ 1516 if (status & STM32F7_I2C_ISR_BERR) { 1517 dev_err(dev, "Bus error accessing addr 0x%x\n", addr); 1518 writel_relaxed(STM32F7_I2C_ICR_BERRCF, base + STM32F7_I2C_ICR); 1519 stm32f7_i2c_release_bus(&i2c_dev->adap); 1520 f7_msg->result = -EIO; 1521 } 1522 1523 /* Arbitration loss */ 1524 if (status & STM32F7_I2C_ISR_ARLO) { 1525 dev_dbg(dev, "Arbitration loss accessing addr 0x%x\n", addr); 1526 writel_relaxed(STM32F7_I2C_ICR_ARLOCF, base + STM32F7_I2C_ICR); 1527 f7_msg->result = -EAGAIN; 1528 } 1529 1530 if (status & STM32F7_I2C_ISR_PECERR) { 1531 dev_err(dev, "PEC error in reception accessing addr 0x%x\n", addr); 1532 writel_relaxed(STM32F7_I2C_ICR_PECCF, base + STM32F7_I2C_ICR); 1533 f7_msg->result = -EINVAL; 1534 } 1535 1536 if (status & STM32F7_I2C_ISR_ALERT) { 1537 dev_dbg(dev, "SMBus alert received\n"); 1538 writel_relaxed(STM32F7_I2C_ICR_ALERTCF, base + STM32F7_I2C_ICR); 1539 i2c_handle_smbus_alert(i2c_dev->alert->ara); 1540 return IRQ_HANDLED; 1541 } 1542 1543 if (!i2c_dev->slave_running) { 1544 u32 mask; 1545 /* Disable interrupts */ 1546 if (stm32f7_i2c_is_slave_registered(i2c_dev)) 1547 mask = STM32F7_I2C_XFER_IRQ_MASK; 1548 else 1549 mask = STM32F7_I2C_ALL_IRQ_MASK; 1550 stm32f7_i2c_disable_irq(i2c_dev, mask); 1551 } 1552 1553 /* Disable dma */ 1554 if (i2c_dev->use_dma) 1555 stm32f7_i2c_dma_callback(i2c_dev); 1556 1557 i2c_dev->master_mode = false; 1558 complete(&i2c_dev->complete); 1559 1560 return IRQ_HANDLED; 1561 } 1562 1563 #define STM32F7_ERR_EVENTS (STM32F7_I2C_ISR_BERR | STM32F7_I2C_ISR_ARLO |\ 1564 STM32F7_I2C_ISR_PECERR | STM32F7_I2C_ISR_ALERT) 1565 static irqreturn_t stm32f7_i2c_isr_event(int irq, void *data) 1566 { 1567 struct stm32f7_i2c_dev *i2c_dev = data; 1568 u32 status; 1569 1570 status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); 1571 1572 /* 1573 * Check if the interrupt is for a slave device or related 1574 * to errors flags (in case of single it line mode) 1575 */ 1576 if (!i2c_dev->master_mode || 1577 (i2c_dev->setup.single_it_line && (status & STM32F7_ERR_EVENTS))) 1578 return IRQ_WAKE_THREAD; 1579 1580 /* Tx empty */ 1581 if (status & STM32F7_I2C_ISR_TXIS) 1582 stm32f7_i2c_write_tx_data(i2c_dev); 1583 1584 /* RX not empty */ 1585 if (status & STM32F7_I2C_ISR_RXNE) 1586 stm32f7_i2c_read_rx_data(i2c_dev); 1587 1588 /* Wake up the thread if other flags are raised */ 1589 if (status & 1590 (STM32F7_I2C_ISR_NACKF | STM32F7_I2C_ISR_STOPF | 1591 STM32F7_I2C_ISR_TC | STM32F7_I2C_ISR_TCR)) 1592 return IRQ_WAKE_THREAD; 1593 1594 return IRQ_HANDLED; 1595 } 1596 1597 static irqreturn_t stm32f7_i2c_isr_event_thread(int irq, void *data) 1598 { 1599 struct stm32f7_i2c_dev *i2c_dev = data; 1600 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 1601 void __iomem *base = i2c_dev->base; 1602 u32 status, mask; 1603 int ret; 1604 1605 status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); 1606 1607 if (!i2c_dev->master_mode) 1608 return stm32f7_i2c_slave_isr_event(i2c_dev, status); 1609 1610 /* Handle errors in case of this handler is used for events/errors */ 1611 if (i2c_dev->setup.single_it_line && (status & STM32F7_ERR_EVENTS)) 1612 return stm32f7_i2c_handle_isr_errs(i2c_dev, status); 1613 1614 /* NACK received */ 1615 if (status & STM32F7_I2C_ISR_NACKF) { 1616 dev_dbg(i2c_dev->dev, "<%s>: Receive NACK (addr %x)\n", 1617 __func__, f7_msg->addr); 1618 writel_relaxed(STM32F7_I2C_ICR_NACKCF, base + STM32F7_I2C_ICR); 1619 if (i2c_dev->use_dma) 1620 stm32f7_i2c_dma_callback(i2c_dev); 1621 f7_msg->result = -ENXIO; 1622 } 1623 1624 if (status & STM32F7_I2C_ISR_TCR) { 1625 if (f7_msg->smbus) 1626 stm32f7_i2c_smbus_reload(i2c_dev); 1627 else 1628 stm32f7_i2c_reload(i2c_dev); 1629 } 1630 1631 /* Transfer complete */ 1632 if (status & STM32F7_I2C_ISR_TC) { 1633 /* Wait for dma transfer completion before sending next message */ 1634 if (i2c_dev->use_dma && !f7_msg->result) { 1635 ret = wait_for_completion_timeout(&i2c_dev->dma->dma_complete, HZ); 1636 if (!ret) { 1637 dev_dbg(i2c_dev->dev, "<%s>: Timed out\n", __func__); 1638 stm32f7_i2c_dma_callback(i2c_dev); 1639 f7_msg->result = -ETIMEDOUT; 1640 } 1641 } 1642 if (f7_msg->stop) { 1643 mask = STM32F7_I2C_CR2_STOP; 1644 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR2, mask); 1645 } else if (f7_msg->smbus) { 1646 stm32f7_i2c_smbus_rep_start(i2c_dev); 1647 } else { 1648 i2c_dev->msg_id++; 1649 i2c_dev->msg++; 1650 stm32f7_i2c_xfer_msg(i2c_dev, i2c_dev->msg); 1651 } 1652 } 1653 1654 /* STOP detection flag */ 1655 if (status & STM32F7_I2C_ISR_STOPF) { 1656 /* Disable interrupts */ 1657 if (stm32f7_i2c_is_slave_registered(i2c_dev)) 1658 mask = STM32F7_I2C_XFER_IRQ_MASK; 1659 else 1660 mask = STM32F7_I2C_ALL_IRQ_MASK; 1661 stm32f7_i2c_disable_irq(i2c_dev, mask); 1662 1663 /* Clear STOP flag */ 1664 writel_relaxed(STM32F7_I2C_ICR_STOPCF, base + STM32F7_I2C_ICR); 1665 1666 i2c_dev->master_mode = false; 1667 complete(&i2c_dev->complete); 1668 } 1669 1670 return IRQ_HANDLED; 1671 } 1672 1673 static irqreturn_t stm32f7_i2c_isr_error_thread(int irq, void *data) 1674 { 1675 struct stm32f7_i2c_dev *i2c_dev = data; 1676 u32 status; 1677 1678 status = readl_relaxed(i2c_dev->base + STM32F7_I2C_ISR); 1679 1680 return stm32f7_i2c_handle_isr_errs(i2c_dev, status); 1681 } 1682 1683 static int stm32f7_i2c_wait_polling(struct stm32f7_i2c_dev *i2c_dev) 1684 { 1685 ktime_t timeout = ktime_add_ms(ktime_get(), i2c_dev->adap.timeout); 1686 1687 while (ktime_compare(ktime_get(), timeout) < 0) { 1688 udelay(5); 1689 stm32f7_i2c_isr_event(0, i2c_dev); 1690 1691 if (completion_done(&i2c_dev->complete)) 1692 return 1; 1693 } 1694 1695 return 0; 1696 } 1697 1698 static int stm32f7_i2c_xfer_core(struct i2c_adapter *i2c_adap, 1699 struct i2c_msg msgs[], int num) 1700 { 1701 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap); 1702 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 1703 struct stm32_i2c_dma *dma = i2c_dev->dma; 1704 unsigned long time_left; 1705 int ret; 1706 1707 i2c_dev->msg = msgs; 1708 i2c_dev->msg_num = num; 1709 i2c_dev->msg_id = 0; 1710 f7_msg->smbus = false; 1711 1712 ret = pm_runtime_resume_and_get(i2c_dev->dev); 1713 if (ret < 0) 1714 return ret; 1715 1716 ret = stm32f7_i2c_wait_free_bus(i2c_dev); 1717 if (ret) 1718 goto pm_free; 1719 1720 reinit_completion(&i2c_dev->complete); 1721 1722 stm32f7_i2c_xfer_msg(i2c_dev, msgs); 1723 1724 if (!i2c_dev->atomic) 1725 time_left = wait_for_completion_timeout(&i2c_dev->complete, 1726 i2c_dev->adap.timeout); 1727 else 1728 time_left = stm32f7_i2c_wait_polling(i2c_dev); 1729 1730 ret = f7_msg->result; 1731 if (ret) { 1732 if (i2c_dev->use_dma) 1733 dmaengine_synchronize(dma->chan_using); 1734 1735 /* 1736 * It is possible that some unsent data have already been 1737 * written into TXDR. To avoid sending old data in a 1738 * further transfer, flush TXDR in case of any error 1739 */ 1740 writel_relaxed(STM32F7_I2C_ISR_TXE, 1741 i2c_dev->base + STM32F7_I2C_ISR); 1742 goto pm_free; 1743 } 1744 1745 if (!time_left) { 1746 dev_dbg(i2c_dev->dev, "Access to slave 0x%x timed out\n", 1747 i2c_dev->msg->addr); 1748 if (i2c_dev->use_dma) 1749 dmaengine_terminate_sync(dma->chan_using); 1750 stm32f7_i2c_wait_free_bus(i2c_dev); 1751 ret = -ETIMEDOUT; 1752 } 1753 1754 pm_free: 1755 pm_runtime_put_autosuspend(i2c_dev->dev); 1756 1757 return (ret < 0) ? ret : num; 1758 } 1759 1760 static int stm32f7_i2c_xfer(struct i2c_adapter *i2c_adap, 1761 struct i2c_msg msgs[], int num) 1762 { 1763 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap); 1764 1765 i2c_dev->atomic = false; 1766 return stm32f7_i2c_xfer_core(i2c_adap, msgs, num); 1767 } 1768 1769 static int stm32f7_i2c_xfer_atomic(struct i2c_adapter *i2c_adap, 1770 struct i2c_msg msgs[], int num) 1771 { 1772 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap); 1773 1774 i2c_dev->atomic = true; 1775 return stm32f7_i2c_xfer_core(i2c_adap, msgs, num); 1776 } 1777 1778 static int stm32f7_i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, 1779 unsigned short flags, char read_write, 1780 u8 command, int size, 1781 union i2c_smbus_data *data) 1782 { 1783 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(adapter); 1784 struct stm32f7_i2c_msg *f7_msg = &i2c_dev->f7_msg; 1785 struct stm32_i2c_dma *dma = i2c_dev->dma; 1786 struct device *dev = i2c_dev->dev; 1787 unsigned long time_left; 1788 int i, ret; 1789 1790 f7_msg->addr = addr; 1791 f7_msg->size = size; 1792 f7_msg->read_write = read_write; 1793 f7_msg->smbus = true; 1794 1795 ret = pm_runtime_resume_and_get(dev); 1796 if (ret < 0) 1797 return ret; 1798 1799 ret = stm32f7_i2c_wait_free_bus(i2c_dev); 1800 if (ret) 1801 goto pm_free; 1802 1803 ret = stm32f7_i2c_smbus_xfer_msg(i2c_dev, flags, command, data); 1804 if (ret) 1805 goto pm_free; 1806 1807 time_left = wait_for_completion_timeout(&i2c_dev->complete, 1808 i2c_dev->adap.timeout); 1809 ret = f7_msg->result; 1810 if (ret) { 1811 if (i2c_dev->use_dma) 1812 dmaengine_synchronize(dma->chan_using); 1813 1814 /* 1815 * It is possible that some unsent data have already been 1816 * written into TXDR. To avoid sending old data in a 1817 * further transfer, flush TXDR in case of any error 1818 */ 1819 writel_relaxed(STM32F7_I2C_ISR_TXE, 1820 i2c_dev->base + STM32F7_I2C_ISR); 1821 goto pm_free; 1822 } 1823 1824 if (!time_left) { 1825 dev_dbg(dev, "Access to slave 0x%x timed out\n", f7_msg->addr); 1826 if (i2c_dev->use_dma) 1827 dmaengine_terminate_sync(dma->chan_using); 1828 stm32f7_i2c_wait_free_bus(i2c_dev); 1829 ret = -ETIMEDOUT; 1830 goto pm_free; 1831 } 1832 1833 /* Check PEC */ 1834 if ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK && read_write) { 1835 ret = stm32f7_i2c_smbus_check_pec(i2c_dev); 1836 if (ret) 1837 goto pm_free; 1838 } 1839 1840 if (read_write && size != I2C_SMBUS_QUICK) { 1841 switch (size) { 1842 case I2C_SMBUS_BYTE: 1843 case I2C_SMBUS_BYTE_DATA: 1844 data->byte = f7_msg->smbus_buf[0]; 1845 break; 1846 case I2C_SMBUS_WORD_DATA: 1847 case I2C_SMBUS_PROC_CALL: 1848 data->word = f7_msg->smbus_buf[0] | 1849 (f7_msg->smbus_buf[1] << 8); 1850 break; 1851 case I2C_SMBUS_BLOCK_DATA: 1852 case I2C_SMBUS_BLOCK_PROC_CALL: 1853 for (i = 0; i <= f7_msg->smbus_buf[0]; i++) 1854 data->block[i] = f7_msg->smbus_buf[i]; 1855 break; 1856 default: 1857 dev_err(dev, "Unsupported smbus transaction\n"); 1858 ret = -EINVAL; 1859 } 1860 } 1861 1862 pm_free: 1863 pm_runtime_put_autosuspend(dev); 1864 return ret; 1865 } 1866 1867 static void stm32f7_i2c_enable_wakeup(struct stm32f7_i2c_dev *i2c_dev, 1868 bool enable) 1869 { 1870 void __iomem *base = i2c_dev->base; 1871 u32 mask = STM32F7_I2C_CR1_WUPEN; 1872 1873 if (!i2c_dev->wakeup_src) 1874 return; 1875 1876 if (enable) { 1877 device_set_wakeup_enable(i2c_dev->dev, true); 1878 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask); 1879 } else { 1880 device_set_wakeup_enable(i2c_dev->dev, false); 1881 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, mask); 1882 } 1883 } 1884 1885 static int stm32f7_i2c_reg_slave(struct i2c_client *slave) 1886 { 1887 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter); 1888 void __iomem *base = i2c_dev->base; 1889 struct device *dev = i2c_dev->dev; 1890 u32 oar1, oar2, mask; 1891 int id, ret; 1892 1893 if (slave->flags & I2C_CLIENT_PEC) { 1894 dev_err(dev, "SMBus PEC not supported in slave mode\n"); 1895 return -EINVAL; 1896 } 1897 1898 if (stm32f7_i2c_is_slave_busy(i2c_dev)) { 1899 dev_err(dev, "Too much slave registered\n"); 1900 return -EBUSY; 1901 } 1902 1903 ret = stm32f7_i2c_get_free_slave_id(i2c_dev, slave, &id); 1904 if (ret) 1905 return ret; 1906 1907 ret = pm_runtime_resume_and_get(dev); 1908 if (ret < 0) 1909 return ret; 1910 1911 if (!stm32f7_i2c_is_slave_registered(i2c_dev)) 1912 stm32f7_i2c_enable_wakeup(i2c_dev, true); 1913 1914 switch (id) { 1915 case 0: 1916 /* Slave SMBus Host */ 1917 i2c_dev->slave[id] = slave; 1918 break; 1919 1920 case 1: 1921 /* Configure Own Address 1 */ 1922 oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1); 1923 oar1 &= ~STM32F7_I2C_OAR1_MASK; 1924 if (slave->flags & I2C_CLIENT_TEN) { 1925 oar1 |= STM32F7_I2C_OAR1_OA1_10(slave->addr); 1926 oar1 |= STM32F7_I2C_OAR1_OA1MODE; 1927 } else { 1928 oar1 |= STM32F7_I2C_OAR1_OA1_7(slave->addr); 1929 } 1930 oar1 |= STM32F7_I2C_OAR1_OA1EN; 1931 i2c_dev->slave[id] = slave; 1932 writel_relaxed(oar1, i2c_dev->base + STM32F7_I2C_OAR1); 1933 break; 1934 1935 case 2: 1936 /* Configure Own Address 2 */ 1937 oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2); 1938 oar2 &= ~STM32F7_I2C_OAR2_MASK; 1939 if (slave->flags & I2C_CLIENT_TEN) { 1940 ret = -EOPNOTSUPP; 1941 goto pm_free; 1942 } 1943 1944 oar2 |= STM32F7_I2C_OAR2_OA2_7(slave->addr); 1945 oar2 |= STM32F7_I2C_OAR2_OA2EN; 1946 i2c_dev->slave[id] = slave; 1947 writel_relaxed(oar2, i2c_dev->base + STM32F7_I2C_OAR2); 1948 break; 1949 1950 default: 1951 dev_err(dev, "I2C slave id not supported\n"); 1952 ret = -ENODEV; 1953 goto pm_free; 1954 } 1955 1956 /* Enable ACK */ 1957 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR2, STM32F7_I2C_CR2_NACK); 1958 1959 /* Enable Address match interrupt, error interrupt and enable I2C */ 1960 mask = STM32F7_I2C_CR1_ADDRIE | STM32F7_I2C_CR1_ERRIE | 1961 STM32F7_I2C_CR1_PE; 1962 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, mask); 1963 1964 ret = 0; 1965 pm_free: 1966 if (!stm32f7_i2c_is_slave_registered(i2c_dev)) 1967 stm32f7_i2c_enable_wakeup(i2c_dev, false); 1968 1969 pm_runtime_put_autosuspend(dev); 1970 1971 return ret; 1972 } 1973 1974 static int stm32f7_i2c_unreg_slave(struct i2c_client *slave) 1975 { 1976 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(slave->adapter); 1977 void __iomem *base = i2c_dev->base; 1978 u32 mask; 1979 int id, ret; 1980 1981 ret = stm32f7_i2c_get_slave_id(i2c_dev, slave, &id); 1982 if (ret) 1983 return ret; 1984 1985 WARN_ON(!i2c_dev->slave[id]); 1986 1987 ret = pm_runtime_resume_and_get(i2c_dev->dev); 1988 if (ret < 0) 1989 return ret; 1990 1991 if (id == 1) { 1992 mask = STM32F7_I2C_OAR1_OA1EN; 1993 stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR1, mask); 1994 } else if (id == 2) { 1995 mask = STM32F7_I2C_OAR2_OA2EN; 1996 stm32f7_i2c_clr_bits(base + STM32F7_I2C_OAR2, mask); 1997 } 1998 1999 i2c_dev->slave[id] = NULL; 2000 2001 if (!stm32f7_i2c_is_slave_registered(i2c_dev)) { 2002 stm32f7_i2c_disable_irq(i2c_dev, STM32F7_I2C_ALL_IRQ_MASK); 2003 stm32f7_i2c_enable_wakeup(i2c_dev, false); 2004 } 2005 2006 pm_runtime_put_autosuspend(i2c_dev->dev); 2007 2008 return 0; 2009 } 2010 2011 static int stm32f7_i2c_write_fm_plus_bits(struct stm32f7_i2c_dev *i2c_dev, 2012 bool enable) 2013 { 2014 int ret = 0; 2015 2016 if (i2c_dev->bus_rate <= I2C_MAX_FAST_MODE_FREQ || 2017 (!i2c_dev->setup.fmp_cr1_bit && IS_ERR_OR_NULL(i2c_dev->regmap))) 2018 /* Optional */ 2019 return 0; 2020 2021 if (i2c_dev->setup.fmp_cr1_bit) { 2022 if (enable) 2023 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, STM32_I2C_CR1_FMP); 2024 else 2025 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, STM32_I2C_CR1_FMP); 2026 } else { 2027 if (i2c_dev->fmp_sreg == i2c_dev->fmp_creg) 2028 ret = regmap_update_bits(i2c_dev->regmap, i2c_dev->fmp_sreg, 2029 i2c_dev->fmp_mask, enable ? i2c_dev->fmp_mask : 0); 2030 else 2031 ret = regmap_write(i2c_dev->regmap, 2032 enable ? i2c_dev->fmp_sreg : i2c_dev->fmp_creg, 2033 i2c_dev->fmp_mask); 2034 } 2035 2036 return ret; 2037 } 2038 2039 static int stm32f7_i2c_setup_fm_plus_bits(struct platform_device *pdev, 2040 struct stm32f7_i2c_dev *i2c_dev) 2041 { 2042 struct device_node *np = pdev->dev.of_node; 2043 int ret; 2044 2045 i2c_dev->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg-fmp"); 2046 if (IS_ERR(i2c_dev->regmap)) 2047 /* Optional */ 2048 return 0; 2049 2050 ret = of_property_read_u32_index(np, "st,syscfg-fmp", 1, 2051 &i2c_dev->fmp_sreg); 2052 if (ret) 2053 return ret; 2054 2055 i2c_dev->fmp_creg = i2c_dev->fmp_sreg + 2056 i2c_dev->setup.fmp_clr_offset; 2057 2058 return of_property_read_u32_index(np, "st,syscfg-fmp", 2, 2059 &i2c_dev->fmp_mask); 2060 } 2061 2062 static int stm32f7_i2c_enable_smbus_host(struct stm32f7_i2c_dev *i2c_dev) 2063 { 2064 struct i2c_adapter *adap = &i2c_dev->adap; 2065 void __iomem *base = i2c_dev->base; 2066 struct i2c_client *client; 2067 2068 client = i2c_new_slave_host_notify_device(adap); 2069 if (IS_ERR(client)) 2070 return PTR_ERR(client); 2071 2072 i2c_dev->host_notify_client = client; 2073 2074 /* Enable SMBus Host address */ 2075 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, STM32F7_I2C_CR1_SMBHEN); 2076 2077 return 0; 2078 } 2079 2080 static void stm32f7_i2c_disable_smbus_host(struct stm32f7_i2c_dev *i2c_dev) 2081 { 2082 void __iomem *base = i2c_dev->base; 2083 2084 if (i2c_dev->host_notify_client) { 2085 /* Disable SMBus Host address */ 2086 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, 2087 STM32F7_I2C_CR1_SMBHEN); 2088 i2c_free_slave_host_notify_device(i2c_dev->host_notify_client); 2089 } 2090 } 2091 2092 static int stm32f7_i2c_enable_smbus_alert(struct stm32f7_i2c_dev *i2c_dev) 2093 { 2094 struct stm32f7_i2c_alert *alert; 2095 struct i2c_adapter *adap = &i2c_dev->adap; 2096 struct device *dev = i2c_dev->dev; 2097 void __iomem *base = i2c_dev->base; 2098 2099 alert = devm_kzalloc(dev, sizeof(*alert), GFP_KERNEL); 2100 if (!alert) 2101 return -ENOMEM; 2102 2103 alert->ara = i2c_new_smbus_alert_device(adap, &alert->setup); 2104 if (IS_ERR(alert->ara)) 2105 return PTR_ERR(alert->ara); 2106 2107 i2c_dev->alert = alert; 2108 2109 /* Enable SMBus Alert */ 2110 stm32f7_i2c_set_bits(base + STM32F7_I2C_CR1, STM32F7_I2C_CR1_ALERTEN); 2111 2112 return 0; 2113 } 2114 2115 static void stm32f7_i2c_disable_smbus_alert(struct stm32f7_i2c_dev *i2c_dev) 2116 { 2117 struct stm32f7_i2c_alert *alert = i2c_dev->alert; 2118 void __iomem *base = i2c_dev->base; 2119 2120 if (alert) { 2121 /* Disable SMBus Alert */ 2122 stm32f7_i2c_clr_bits(base + STM32F7_I2C_CR1, 2123 STM32F7_I2C_CR1_ALERTEN); 2124 i2c_unregister_device(alert->ara); 2125 } 2126 } 2127 2128 static u32 stm32f7_i2c_func(struct i2c_adapter *adap) 2129 { 2130 struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(adap); 2131 2132 u32 func = I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SLAVE | 2133 I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | 2134 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | 2135 I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL | 2136 I2C_FUNC_SMBUS_PROC_CALL | I2C_FUNC_SMBUS_PEC | 2137 I2C_FUNC_SMBUS_I2C_BLOCK; 2138 2139 if (i2c_dev->smbus_mode) 2140 func |= I2C_FUNC_SMBUS_HOST_NOTIFY; 2141 2142 return func; 2143 } 2144 2145 static const struct i2c_algorithm stm32f7_i2c_algo = { 2146 .xfer = stm32f7_i2c_xfer, 2147 .xfer_atomic = stm32f7_i2c_xfer_atomic, 2148 .smbus_xfer = stm32f7_i2c_smbus_xfer, 2149 .functionality = stm32f7_i2c_func, 2150 .reg_slave = stm32f7_i2c_reg_slave, 2151 .unreg_slave = stm32f7_i2c_unreg_slave, 2152 }; 2153 2154 static int stm32f7_i2c_probe(struct platform_device *pdev) 2155 { 2156 struct stm32f7_i2c_dev *i2c_dev; 2157 const struct stm32f7_i2c_setup *setup; 2158 struct resource *res; 2159 struct i2c_adapter *adap; 2160 struct reset_control *rst; 2161 dma_addr_t phy_addr; 2162 int irq_error, irq_event, ret; 2163 2164 i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL); 2165 if (!i2c_dev) 2166 return -ENOMEM; 2167 2168 setup = of_device_get_match_data(&pdev->dev); 2169 if (!setup) 2170 return dev_err_probe(&pdev->dev, -ENODEV, "Can't get device data\n"); 2171 i2c_dev->setup = *setup; 2172 2173 i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); 2174 if (IS_ERR(i2c_dev->base)) 2175 return PTR_ERR(i2c_dev->base); 2176 phy_addr = (dma_addr_t)res->start; 2177 2178 irq_event = platform_get_irq(pdev, 0); 2179 if (irq_event < 0) 2180 return irq_event; 2181 2182 i2c_dev->wakeup_src = of_property_read_bool(pdev->dev.of_node, 2183 "wakeup-source"); 2184 2185 i2c_dev->clk = devm_clk_get_enabled(&pdev->dev, NULL); 2186 if (IS_ERR(i2c_dev->clk)) 2187 return dev_err_probe(&pdev->dev, PTR_ERR(i2c_dev->clk), 2188 "Failed to enable controller clock\n"); 2189 2190 rst = devm_reset_control_get(&pdev->dev, NULL); 2191 if (IS_ERR(rst)) 2192 return dev_err_probe(&pdev->dev, PTR_ERR(rst), 2193 "Error: Missing reset ctrl\n"); 2194 2195 reset_control_assert(rst); 2196 udelay(2); 2197 reset_control_deassert(rst); 2198 2199 i2c_dev->dev = &pdev->dev; 2200 2201 ret = devm_request_threaded_irq(&pdev->dev, irq_event, 2202 stm32f7_i2c_isr_event, 2203 stm32f7_i2c_isr_event_thread, 2204 IRQF_ONESHOT, 2205 pdev->name, i2c_dev); 2206 if (ret) 2207 return dev_err_probe(&pdev->dev, ret, "Failed to request irq event\n"); 2208 2209 if (!i2c_dev->setup.single_it_line) { 2210 irq_error = platform_get_irq(pdev, 1); 2211 if (irq_error < 0) 2212 return irq_error; 2213 2214 ret = devm_request_threaded_irq(&pdev->dev, irq_error, 2215 NULL, 2216 stm32f7_i2c_isr_error_thread, 2217 IRQF_ONESHOT, 2218 pdev->name, i2c_dev); 2219 if (ret) 2220 return dev_err_probe(&pdev->dev, ret, "Failed to request irq error\n"); 2221 } 2222 2223 ret = stm32f7_i2c_setup_timing(i2c_dev, &i2c_dev->setup); 2224 if (ret) 2225 return ret; 2226 2227 /* Setup Fast mode plus if necessary */ 2228 if (i2c_dev->bus_rate > I2C_MAX_FAST_MODE_FREQ) { 2229 if (!i2c_dev->setup.fmp_cr1_bit) { 2230 ret = stm32f7_i2c_setup_fm_plus_bits(pdev, i2c_dev); 2231 if (ret) 2232 return ret; 2233 } 2234 2235 ret = stm32f7_i2c_write_fm_plus_bits(i2c_dev, true); 2236 if (ret) 2237 return ret; 2238 } 2239 2240 adap = &i2c_dev->adap; 2241 i2c_set_adapdata(adap, i2c_dev); 2242 snprintf(adap->name, sizeof(adap->name), "STM32F7 I2C(%pa)", 2243 &res->start); 2244 adap->owner = THIS_MODULE; 2245 adap->timeout = 8 * HZ; 2246 adap->retries = 3; 2247 adap->algo = &stm32f7_i2c_algo; 2248 adap->dev.parent = &pdev->dev; 2249 adap->dev.of_node = pdev->dev.of_node; 2250 2251 init_completion(&i2c_dev->complete); 2252 2253 /* Init DMA config if supported */ 2254 i2c_dev->dma = stm32_i2c_dma_request(i2c_dev->dev, phy_addr, 2255 STM32F7_I2C_TXDR, 2256 STM32F7_I2C_RXDR); 2257 if (IS_ERR(i2c_dev->dma)) { 2258 ret = PTR_ERR(i2c_dev->dma); 2259 /* DMA support is optional, only report other errors */ 2260 if (ret != -ENODEV) 2261 goto fmp_clear; 2262 dev_dbg(i2c_dev->dev, "No DMA option: fallback using interrupts\n"); 2263 i2c_dev->dma = NULL; 2264 } 2265 2266 if (i2c_dev->wakeup_src) { 2267 device_set_wakeup_capable(i2c_dev->dev, true); 2268 2269 ret = dev_pm_set_wake_irq(i2c_dev->dev, irq_event); 2270 if (ret) { 2271 dev_err_probe(i2c_dev->dev, ret, "Failed to set wake up irq\n"); 2272 goto clr_wakeup_capable; 2273 } 2274 } 2275 2276 platform_set_drvdata(pdev, i2c_dev); 2277 2278 pm_runtime_set_autosuspend_delay(i2c_dev->dev, 2279 STM32F7_AUTOSUSPEND_DELAY); 2280 pm_runtime_use_autosuspend(i2c_dev->dev); 2281 pm_runtime_set_active(i2c_dev->dev); 2282 pm_runtime_enable(i2c_dev->dev); 2283 2284 pm_runtime_get_noresume(&pdev->dev); 2285 2286 stm32f7_i2c_hw_config(i2c_dev); 2287 2288 i2c_dev->smbus_mode = of_property_read_bool(pdev->dev.of_node, "smbus"); 2289 2290 ret = i2c_add_adapter(adap); 2291 if (ret) 2292 goto pm_disable; 2293 2294 if (i2c_dev->smbus_mode) { 2295 ret = stm32f7_i2c_enable_smbus_host(i2c_dev); 2296 if (ret) { 2297 dev_err_probe(i2c_dev->dev, ret, 2298 "failed to enable SMBus Host-Notify protocol\n"); 2299 goto i2c_adapter_remove; 2300 } 2301 } 2302 2303 if (of_property_read_bool(pdev->dev.of_node, "smbus-alert")) { 2304 ret = stm32f7_i2c_enable_smbus_alert(i2c_dev); 2305 if (ret) { 2306 dev_err_probe(i2c_dev->dev, ret, 2307 "failed to enable SMBus alert protocol\n"); 2308 goto i2c_disable_smbus_host; 2309 } 2310 } 2311 2312 dev_info(i2c_dev->dev, "STM32F7 I2C-%d bus adapter\n", adap->nr); 2313 2314 pm_runtime_put_autosuspend(i2c_dev->dev); 2315 2316 return 0; 2317 2318 i2c_disable_smbus_host: 2319 stm32f7_i2c_disable_smbus_host(i2c_dev); 2320 2321 i2c_adapter_remove: 2322 i2c_del_adapter(adap); 2323 2324 pm_disable: 2325 pm_runtime_put_noidle(i2c_dev->dev); 2326 pm_runtime_disable(i2c_dev->dev); 2327 pm_runtime_set_suspended(i2c_dev->dev); 2328 pm_runtime_dont_use_autosuspend(i2c_dev->dev); 2329 2330 if (i2c_dev->wakeup_src) 2331 dev_pm_clear_wake_irq(i2c_dev->dev); 2332 2333 clr_wakeup_capable: 2334 if (i2c_dev->wakeup_src) 2335 device_set_wakeup_capable(i2c_dev->dev, false); 2336 2337 if (i2c_dev->dma) { 2338 stm32_i2c_dma_free(i2c_dev->dma); 2339 i2c_dev->dma = NULL; 2340 } 2341 2342 fmp_clear: 2343 stm32f7_i2c_write_fm_plus_bits(i2c_dev, false); 2344 2345 return ret; 2346 } 2347 2348 static void stm32f7_i2c_remove(struct platform_device *pdev) 2349 { 2350 struct stm32f7_i2c_dev *i2c_dev = platform_get_drvdata(pdev); 2351 2352 stm32f7_i2c_disable_smbus_alert(i2c_dev); 2353 stm32f7_i2c_disable_smbus_host(i2c_dev); 2354 2355 i2c_del_adapter(&i2c_dev->adap); 2356 pm_runtime_get_sync(i2c_dev->dev); 2357 2358 if (i2c_dev->wakeup_src) { 2359 dev_pm_clear_wake_irq(i2c_dev->dev); 2360 /* 2361 * enforce that wakeup is disabled and that the device 2362 * is marked as non wakeup capable 2363 */ 2364 device_init_wakeup(i2c_dev->dev, false); 2365 } 2366 2367 pm_runtime_put_noidle(i2c_dev->dev); 2368 pm_runtime_disable(i2c_dev->dev); 2369 pm_runtime_set_suspended(i2c_dev->dev); 2370 pm_runtime_dont_use_autosuspend(i2c_dev->dev); 2371 2372 if (i2c_dev->dma) { 2373 stm32_i2c_dma_free(i2c_dev->dma); 2374 i2c_dev->dma = NULL; 2375 } 2376 2377 stm32f7_i2c_write_fm_plus_bits(i2c_dev, false); 2378 } 2379 2380 static int __maybe_unused stm32f7_i2c_runtime_suspend(struct device *dev) 2381 { 2382 struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); 2383 2384 if (!stm32f7_i2c_is_slave_registered(i2c_dev)) 2385 clk_disable(i2c_dev->clk); 2386 2387 return 0; 2388 } 2389 2390 static int __maybe_unused stm32f7_i2c_runtime_resume(struct device *dev) 2391 { 2392 struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); 2393 int ret; 2394 2395 if (!stm32f7_i2c_is_slave_registered(i2c_dev)) { 2396 ret = clk_enable(i2c_dev->clk); 2397 if (ret) { 2398 dev_err(dev, "failed to enable clock\n"); 2399 return ret; 2400 } 2401 } 2402 2403 return 0; 2404 } 2405 2406 static int __maybe_unused stm32f7_i2c_regs_backup(struct stm32f7_i2c_dev *i2c_dev) 2407 { 2408 int ret; 2409 struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs; 2410 2411 ret = pm_runtime_resume_and_get(i2c_dev->dev); 2412 if (ret < 0) 2413 return ret; 2414 2415 backup_regs->cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1); 2416 backup_regs->cr2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR2); 2417 backup_regs->oar1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR1); 2418 backup_regs->oar2 = readl_relaxed(i2c_dev->base + STM32F7_I2C_OAR2); 2419 backup_regs->tmgr = readl_relaxed(i2c_dev->base + STM32F7_I2C_TIMINGR); 2420 stm32f7_i2c_write_fm_plus_bits(i2c_dev, false); 2421 2422 pm_runtime_put_sync(i2c_dev->dev); 2423 2424 return ret; 2425 } 2426 2427 static int __maybe_unused stm32f7_i2c_regs_restore(struct stm32f7_i2c_dev *i2c_dev) 2428 { 2429 u32 cr1; 2430 int ret; 2431 struct stm32f7_i2c_regs *backup_regs = &i2c_dev->backup_regs; 2432 2433 ret = pm_runtime_resume_and_get(i2c_dev->dev); 2434 if (ret < 0) 2435 return ret; 2436 2437 cr1 = readl_relaxed(i2c_dev->base + STM32F7_I2C_CR1); 2438 if (cr1 & STM32F7_I2C_CR1_PE) 2439 stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, 2440 STM32F7_I2C_CR1_PE); 2441 2442 writel_relaxed(backup_regs->tmgr, i2c_dev->base + STM32F7_I2C_TIMINGR); 2443 writel_relaxed(backup_regs->cr1 & ~STM32F7_I2C_CR1_PE, 2444 i2c_dev->base + STM32F7_I2C_CR1); 2445 if (backup_regs->cr1 & STM32F7_I2C_CR1_PE) 2446 stm32f7_i2c_set_bits(i2c_dev->base + STM32F7_I2C_CR1, 2447 STM32F7_I2C_CR1_PE); 2448 writel_relaxed(backup_regs->cr2, i2c_dev->base + STM32F7_I2C_CR2); 2449 writel_relaxed(backup_regs->oar1, i2c_dev->base + STM32F7_I2C_OAR1); 2450 writel_relaxed(backup_regs->oar2, i2c_dev->base + STM32F7_I2C_OAR2); 2451 stm32f7_i2c_write_fm_plus_bits(i2c_dev, true); 2452 2453 pm_runtime_put_sync(i2c_dev->dev); 2454 2455 return ret; 2456 } 2457 2458 static int __maybe_unused stm32f7_i2c_suspend(struct device *dev) 2459 { 2460 struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); 2461 int ret; 2462 2463 i2c_mark_adapter_suspended(&i2c_dev->adap); 2464 2465 if (!device_may_wakeup(dev) && !device_wakeup_path(dev)) { 2466 ret = stm32f7_i2c_regs_backup(i2c_dev); 2467 if (ret < 0) { 2468 i2c_mark_adapter_resumed(&i2c_dev->adap); 2469 return ret; 2470 } 2471 2472 pinctrl_pm_select_sleep_state(dev); 2473 pm_runtime_force_suspend(dev); 2474 } 2475 2476 return 0; 2477 } 2478 2479 static int __maybe_unused stm32f7_i2c_resume(struct device *dev) 2480 { 2481 struct stm32f7_i2c_dev *i2c_dev = dev_get_drvdata(dev); 2482 int ret; 2483 2484 if (!device_may_wakeup(dev) && !device_wakeup_path(dev)) { 2485 ret = pm_runtime_force_resume(dev); 2486 if (ret < 0) 2487 return ret; 2488 pinctrl_pm_select_default_state(dev); 2489 2490 ret = stm32f7_i2c_regs_restore(i2c_dev); 2491 if (ret < 0) 2492 return ret; 2493 } 2494 2495 i2c_mark_adapter_resumed(&i2c_dev->adap); 2496 2497 return 0; 2498 } 2499 2500 static const struct dev_pm_ops stm32f7_i2c_pm_ops = { 2501 SET_RUNTIME_PM_OPS(stm32f7_i2c_runtime_suspend, 2502 stm32f7_i2c_runtime_resume, NULL) 2503 SET_SYSTEM_SLEEP_PM_OPS(stm32f7_i2c_suspend, stm32f7_i2c_resume) 2504 }; 2505 2506 static const struct of_device_id stm32f7_i2c_match[] = { 2507 { .compatible = "st,stm32f7-i2c", .data = &stm32f7_setup}, 2508 { .compatible = "st,stm32mp15-i2c", .data = &stm32mp15_setup}, 2509 { .compatible = "st,stm32mp13-i2c", .data = &stm32mp13_setup}, 2510 { .compatible = "st,stm32mp25-i2c", .data = &stm32mp25_setup}, 2511 {}, 2512 }; 2513 MODULE_DEVICE_TABLE(of, stm32f7_i2c_match); 2514 2515 static struct platform_driver stm32f7_i2c_driver = { 2516 .driver = { 2517 .name = "stm32f7-i2c", 2518 .of_match_table = stm32f7_i2c_match, 2519 .pm = &stm32f7_i2c_pm_ops, 2520 }, 2521 .probe = stm32f7_i2c_probe, 2522 .remove = stm32f7_i2c_remove, 2523 }; 2524 2525 module_platform_driver(stm32f7_i2c_driver); 2526 2527 MODULE_AUTHOR("M'boumba Cedric Madianga <cedric.madianga@gmail.com>"); 2528 MODULE_DESCRIPTION("STMicroelectronics STM32F7 I2C driver"); 2529 MODULE_LICENSE("GPL v2"); 2530