1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2014 MediaTek Inc. 4 * Author: Xudong Chen <xudong.chen@mediatek.com> 5 */ 6 7 #include <linux/clk.h> 8 #include <linux/completion.h> 9 #include <linux/delay.h> 10 #include <linux/device.h> 11 #include <linux/dma-mapping.h> 12 #include <linux/err.h> 13 #include <linux/errno.h> 14 #include <linux/i2c.h> 15 #include <linux/init.h> 16 #include <linux/interrupt.h> 17 #include <linux/io.h> 18 #include <linux/kernel.h> 19 #include <linux/mm.h> 20 #include <linux/module.h> 21 #include <linux/of_address.h> 22 #include <linux/of_device.h> 23 #include <linux/of_irq.h> 24 #include <linux/platform_device.h> 25 #include <linux/scatterlist.h> 26 #include <linux/sched.h> 27 #include <linux/slab.h> 28 29 #define I2C_RS_TRANSFER (1 << 4) 30 #define I2C_ARB_LOST (1 << 3) 31 #define I2C_HS_NACKERR (1 << 2) 32 #define I2C_ACKERR (1 << 1) 33 #define I2C_TRANSAC_COMP (1 << 0) 34 #define I2C_TRANSAC_START (1 << 0) 35 #define I2C_RS_MUL_CNFG (1 << 15) 36 #define I2C_RS_MUL_TRIG (1 << 14) 37 #define I2C_DCM_DISABLE 0x0000 38 #define I2C_IO_CONFIG_OPEN_DRAIN 0x0003 39 #define I2C_IO_CONFIG_PUSH_PULL 0x0000 40 #define I2C_SOFT_RST 0x0001 41 #define I2C_HANDSHAKE_RST 0x0020 42 #define I2C_FIFO_ADDR_CLR 0x0001 43 #define I2C_DELAY_LEN 0x0002 44 #define I2C_TIME_CLR_VALUE 0x0000 45 #define I2C_TIME_DEFAULT_VALUE 0x0003 46 #define I2C_WRRD_TRANAC_VALUE 0x0002 47 #define I2C_RD_TRANAC_VALUE 0x0001 48 #define I2C_SCL_MIS_COMP_VALUE 0x0000 49 #define I2C_CHN_CLR_FLAG 0x0000 50 51 #define I2C_DMA_CON_TX 0x0000 52 #define I2C_DMA_CON_RX 0x0001 53 #define I2C_DMA_ASYNC_MODE 0x0004 54 #define I2C_DMA_SKIP_CONFIG 0x0010 55 #define I2C_DMA_DIR_CHANGE 0x0200 56 #define I2C_DMA_START_EN 0x0001 57 #define I2C_DMA_INT_FLAG_NONE 0x0000 58 #define I2C_DMA_CLR_FLAG 0x0000 59 #define I2C_DMA_WARM_RST 0x0001 60 #define I2C_DMA_HARD_RST 0x0002 61 #define I2C_DMA_HANDSHAKE_RST 0x0004 62 63 #define MAX_SAMPLE_CNT_DIV 8 64 #define MAX_STEP_CNT_DIV 64 65 #define MAX_CLOCK_DIV 256 66 #define MAX_HS_STEP_CNT_DIV 8 67 #define I2C_STANDARD_MODE_BUFFER (1000 / 2) 68 #define I2C_FAST_MODE_BUFFER (300 / 2) 69 #define I2C_FAST_MODE_PLUS_BUFFER (20 / 2) 70 71 #define I2C_CONTROL_RS (0x1 << 1) 72 #define I2C_CONTROL_DMA_EN (0x1 << 2) 73 #define I2C_CONTROL_CLK_EXT_EN (0x1 << 3) 74 #define I2C_CONTROL_DIR_CHANGE (0x1 << 4) 75 #define I2C_CONTROL_ACKERR_DET_EN (0x1 << 5) 76 #define I2C_CONTROL_TRANSFER_LEN_CHANGE (0x1 << 6) 77 #define I2C_CONTROL_DMAACK_EN (0x1 << 8) 78 #define I2C_CONTROL_ASYNC_MODE (0x1 << 9) 79 #define I2C_CONTROL_WRAPPER (0x1 << 0) 80 81 #define I2C_DRV_NAME "i2c-mt65xx" 82 83 enum DMA_REGS_OFFSET { 84 OFFSET_INT_FLAG = 0x0, 85 OFFSET_INT_EN = 0x04, 86 OFFSET_EN = 0x08, 87 OFFSET_RST = 0x0c, 88 OFFSET_CON = 0x18, 89 OFFSET_TX_MEM_ADDR = 0x1c, 90 OFFSET_RX_MEM_ADDR = 0x20, 91 OFFSET_TX_LEN = 0x24, 92 OFFSET_RX_LEN = 0x28, 93 OFFSET_TX_4G_MODE = 0x54, 94 OFFSET_RX_4G_MODE = 0x58, 95 }; 96 97 enum i2c_trans_st_rs { 98 I2C_TRANS_STOP = 0, 99 I2C_TRANS_REPEATED_START, 100 }; 101 102 enum mtk_trans_op { 103 I2C_MASTER_WR = 1, 104 I2C_MASTER_RD, 105 I2C_MASTER_WRRD, 106 }; 107 108 enum I2C_REGS_OFFSET { 109 OFFSET_DATA_PORT, 110 OFFSET_SLAVE_ADDR, 111 OFFSET_INTR_MASK, 112 OFFSET_INTR_STAT, 113 OFFSET_CONTROL, 114 OFFSET_TRANSFER_LEN, 115 OFFSET_TRANSAC_LEN, 116 OFFSET_DELAY_LEN, 117 OFFSET_TIMING, 118 OFFSET_START, 119 OFFSET_EXT_CONF, 120 OFFSET_FIFO_STAT, 121 OFFSET_FIFO_THRESH, 122 OFFSET_FIFO_ADDR_CLR, 123 OFFSET_IO_CONFIG, 124 OFFSET_RSV_DEBUG, 125 OFFSET_HS, 126 OFFSET_SOFTRESET, 127 OFFSET_DCM_EN, 128 OFFSET_PATH_DIR, 129 OFFSET_DEBUGSTAT, 130 OFFSET_DEBUGCTRL, 131 OFFSET_TRANSFER_LEN_AUX, 132 OFFSET_CLOCK_DIV, 133 OFFSET_LTIMING, 134 OFFSET_SCL_HIGH_LOW_RATIO, 135 OFFSET_HS_SCL_HIGH_LOW_RATIO, 136 OFFSET_SCL_MIS_COMP_POINT, 137 OFFSET_STA_STO_AC_TIMING, 138 OFFSET_HS_STA_STO_AC_TIMING, 139 OFFSET_SDA_TIMING, 140 }; 141 142 static const u16 mt_i2c_regs_v1[] = { 143 [OFFSET_DATA_PORT] = 0x0, 144 [OFFSET_SLAVE_ADDR] = 0x4, 145 [OFFSET_INTR_MASK] = 0x8, 146 [OFFSET_INTR_STAT] = 0xc, 147 [OFFSET_CONTROL] = 0x10, 148 [OFFSET_TRANSFER_LEN] = 0x14, 149 [OFFSET_TRANSAC_LEN] = 0x18, 150 [OFFSET_DELAY_LEN] = 0x1c, 151 [OFFSET_TIMING] = 0x20, 152 [OFFSET_START] = 0x24, 153 [OFFSET_EXT_CONF] = 0x28, 154 [OFFSET_FIFO_STAT] = 0x30, 155 [OFFSET_FIFO_THRESH] = 0x34, 156 [OFFSET_FIFO_ADDR_CLR] = 0x38, 157 [OFFSET_IO_CONFIG] = 0x40, 158 [OFFSET_RSV_DEBUG] = 0x44, 159 [OFFSET_HS] = 0x48, 160 [OFFSET_SOFTRESET] = 0x50, 161 [OFFSET_DCM_EN] = 0x54, 162 [OFFSET_PATH_DIR] = 0x60, 163 [OFFSET_DEBUGSTAT] = 0x64, 164 [OFFSET_DEBUGCTRL] = 0x68, 165 [OFFSET_TRANSFER_LEN_AUX] = 0x6c, 166 [OFFSET_CLOCK_DIV] = 0x70, 167 [OFFSET_SCL_HIGH_LOW_RATIO] = 0x74, 168 [OFFSET_HS_SCL_HIGH_LOW_RATIO] = 0x78, 169 [OFFSET_SCL_MIS_COMP_POINT] = 0x7C, 170 [OFFSET_STA_STO_AC_TIMING] = 0x80, 171 [OFFSET_HS_STA_STO_AC_TIMING] = 0x84, 172 [OFFSET_SDA_TIMING] = 0x88, 173 }; 174 175 static const u16 mt_i2c_regs_v2[] = { 176 [OFFSET_DATA_PORT] = 0x0, 177 [OFFSET_SLAVE_ADDR] = 0x4, 178 [OFFSET_INTR_MASK] = 0x8, 179 [OFFSET_INTR_STAT] = 0xc, 180 [OFFSET_CONTROL] = 0x10, 181 [OFFSET_TRANSFER_LEN] = 0x14, 182 [OFFSET_TRANSAC_LEN] = 0x18, 183 [OFFSET_DELAY_LEN] = 0x1c, 184 [OFFSET_TIMING] = 0x20, 185 [OFFSET_START] = 0x24, 186 [OFFSET_EXT_CONF] = 0x28, 187 [OFFSET_LTIMING] = 0x2c, 188 [OFFSET_HS] = 0x30, 189 [OFFSET_IO_CONFIG] = 0x34, 190 [OFFSET_FIFO_ADDR_CLR] = 0x38, 191 [OFFSET_SDA_TIMING] = 0x3c, 192 [OFFSET_TRANSFER_LEN_AUX] = 0x44, 193 [OFFSET_CLOCK_DIV] = 0x48, 194 [OFFSET_SOFTRESET] = 0x50, 195 [OFFSET_SCL_MIS_COMP_POINT] = 0x90, 196 [OFFSET_DEBUGSTAT] = 0xe0, 197 [OFFSET_DEBUGCTRL] = 0xe8, 198 [OFFSET_FIFO_STAT] = 0xf4, 199 [OFFSET_FIFO_THRESH] = 0xf8, 200 [OFFSET_DCM_EN] = 0xf88, 201 }; 202 203 struct mtk_i2c_compatible { 204 const struct i2c_adapter_quirks *quirks; 205 const u16 *regs; 206 unsigned char pmic_i2c: 1; 207 unsigned char dcm: 1; 208 unsigned char auto_restart: 1; 209 unsigned char aux_len_reg: 1; 210 unsigned char timing_adjust: 1; 211 unsigned char dma_sync: 1; 212 unsigned char ltiming_adjust: 1; 213 unsigned char apdma_sync: 1; 214 unsigned char max_dma_support; 215 }; 216 217 struct mtk_i2c_ac_timing { 218 u16 htiming; 219 u16 ltiming; 220 u16 hs; 221 u16 ext; 222 u16 inter_clk_div; 223 u16 scl_hl_ratio; 224 u16 hs_scl_hl_ratio; 225 u16 sta_stop; 226 u16 hs_sta_stop; 227 u16 sda_timing; 228 }; 229 230 struct mtk_i2c { 231 struct i2c_adapter adap; /* i2c host adapter */ 232 struct device *dev; 233 struct completion msg_complete; 234 struct i2c_timings timing_info; 235 236 /* set in i2c probe */ 237 void __iomem *base; /* i2c base addr */ 238 void __iomem *pdmabase; /* dma base address*/ 239 struct clk *clk_main; /* main clock for i2c bus */ 240 struct clk *clk_dma; /* DMA clock for i2c via DMA */ 241 struct clk *clk_pmic; /* PMIC clock for i2c from PMIC */ 242 struct clk *clk_arb; /* Arbitrator clock for i2c */ 243 bool have_pmic; /* can use i2c pins from PMIC */ 244 bool use_push_pull; /* IO config push-pull mode */ 245 246 u16 irq_stat; /* interrupt status */ 247 unsigned int clk_src_div; 248 unsigned int speed_hz; /* The speed in transfer */ 249 enum mtk_trans_op op; 250 u16 timing_reg; 251 u16 high_speed_reg; 252 u16 ltiming_reg; 253 unsigned char auto_restart; 254 bool ignore_restart_irq; 255 struct mtk_i2c_ac_timing ac_timing; 256 const struct mtk_i2c_compatible *dev_comp; 257 }; 258 259 /** 260 * struct i2c_spec_values: 261 * @min_low_ns: min LOW period of the SCL clock 262 * @min_su_sta_ns: min set-up time for a repeated START condition 263 * @max_hd_dat_ns: max data hold time 264 * @min_su_dat_ns: min data set-up time 265 */ 266 struct i2c_spec_values { 267 unsigned int min_low_ns; 268 unsigned int min_su_sta_ns; 269 unsigned int max_hd_dat_ns; 270 unsigned int min_su_dat_ns; 271 }; 272 273 static const struct i2c_spec_values standard_mode_spec = { 274 .min_low_ns = 4700 + I2C_STANDARD_MODE_BUFFER, 275 .min_su_sta_ns = 4700 + I2C_STANDARD_MODE_BUFFER, 276 .max_hd_dat_ns = 3450 - I2C_STANDARD_MODE_BUFFER, 277 .min_su_dat_ns = 250 + I2C_STANDARD_MODE_BUFFER, 278 }; 279 280 static const struct i2c_spec_values fast_mode_spec = { 281 .min_low_ns = 1300 + I2C_FAST_MODE_BUFFER, 282 .min_su_sta_ns = 600 + I2C_FAST_MODE_BUFFER, 283 .max_hd_dat_ns = 900 - I2C_FAST_MODE_BUFFER, 284 .min_su_dat_ns = 100 + I2C_FAST_MODE_BUFFER, 285 }; 286 287 static const struct i2c_spec_values fast_mode_plus_spec = { 288 .min_low_ns = 500 + I2C_FAST_MODE_PLUS_BUFFER, 289 .min_su_sta_ns = 260 + I2C_FAST_MODE_PLUS_BUFFER, 290 .max_hd_dat_ns = 400 - I2C_FAST_MODE_PLUS_BUFFER, 291 .min_su_dat_ns = 50 + I2C_FAST_MODE_PLUS_BUFFER, 292 }; 293 294 static const struct i2c_adapter_quirks mt6577_i2c_quirks = { 295 .flags = I2C_AQ_COMB_WRITE_THEN_READ, 296 .max_num_msgs = 1, 297 .max_write_len = 255, 298 .max_read_len = 255, 299 .max_comb_1st_msg_len = 255, 300 .max_comb_2nd_msg_len = 31, 301 }; 302 303 static const struct i2c_adapter_quirks mt7622_i2c_quirks = { 304 .max_num_msgs = 255, 305 }; 306 307 static const struct i2c_adapter_quirks mt8183_i2c_quirks = { 308 .flags = I2C_AQ_NO_ZERO_LEN, 309 }; 310 311 static const struct mtk_i2c_compatible mt2712_compat = { 312 .regs = mt_i2c_regs_v1, 313 .pmic_i2c = 0, 314 .dcm = 1, 315 .auto_restart = 1, 316 .aux_len_reg = 1, 317 .timing_adjust = 1, 318 .dma_sync = 0, 319 .ltiming_adjust = 0, 320 .apdma_sync = 0, 321 .max_dma_support = 33, 322 }; 323 324 static const struct mtk_i2c_compatible mt6577_compat = { 325 .quirks = &mt6577_i2c_quirks, 326 .regs = mt_i2c_regs_v1, 327 .pmic_i2c = 0, 328 .dcm = 1, 329 .auto_restart = 0, 330 .aux_len_reg = 0, 331 .timing_adjust = 0, 332 .dma_sync = 0, 333 .ltiming_adjust = 0, 334 .apdma_sync = 0, 335 .max_dma_support = 32, 336 }; 337 338 static const struct mtk_i2c_compatible mt6589_compat = { 339 .quirks = &mt6577_i2c_quirks, 340 .regs = mt_i2c_regs_v1, 341 .pmic_i2c = 1, 342 .dcm = 0, 343 .auto_restart = 0, 344 .aux_len_reg = 0, 345 .timing_adjust = 0, 346 .dma_sync = 0, 347 .ltiming_adjust = 0, 348 .apdma_sync = 0, 349 .max_dma_support = 32, 350 }; 351 352 static const struct mtk_i2c_compatible mt7622_compat = { 353 .quirks = &mt7622_i2c_quirks, 354 .regs = mt_i2c_regs_v1, 355 .pmic_i2c = 0, 356 .dcm = 1, 357 .auto_restart = 1, 358 .aux_len_reg = 1, 359 .timing_adjust = 0, 360 .dma_sync = 0, 361 .ltiming_adjust = 0, 362 .apdma_sync = 0, 363 .max_dma_support = 32, 364 }; 365 366 static const struct mtk_i2c_compatible mt8173_compat = { 367 .regs = mt_i2c_regs_v1, 368 .pmic_i2c = 0, 369 .dcm = 1, 370 .auto_restart = 1, 371 .aux_len_reg = 1, 372 .timing_adjust = 0, 373 .dma_sync = 0, 374 .ltiming_adjust = 0, 375 .apdma_sync = 0, 376 .max_dma_support = 33, 377 }; 378 379 static const struct mtk_i2c_compatible mt8183_compat = { 380 .quirks = &mt8183_i2c_quirks, 381 .regs = mt_i2c_regs_v2, 382 .pmic_i2c = 0, 383 .dcm = 0, 384 .auto_restart = 1, 385 .aux_len_reg = 1, 386 .timing_adjust = 1, 387 .dma_sync = 1, 388 .ltiming_adjust = 1, 389 .apdma_sync = 0, 390 .max_dma_support = 33, 391 }; 392 393 static const struct mtk_i2c_compatible mt8192_compat = { 394 .quirks = &mt8183_i2c_quirks, 395 .regs = mt_i2c_regs_v2, 396 .pmic_i2c = 0, 397 .dcm = 0, 398 .auto_restart = 1, 399 .aux_len_reg = 1, 400 .timing_adjust = 1, 401 .dma_sync = 1, 402 .ltiming_adjust = 1, 403 .apdma_sync = 1, 404 .max_dma_support = 36, 405 }; 406 407 static const struct of_device_id mtk_i2c_of_match[] = { 408 { .compatible = "mediatek,mt2712-i2c", .data = &mt2712_compat }, 409 { .compatible = "mediatek,mt6577-i2c", .data = &mt6577_compat }, 410 { .compatible = "mediatek,mt6589-i2c", .data = &mt6589_compat }, 411 { .compatible = "mediatek,mt7622-i2c", .data = &mt7622_compat }, 412 { .compatible = "mediatek,mt8173-i2c", .data = &mt8173_compat }, 413 { .compatible = "mediatek,mt8183-i2c", .data = &mt8183_compat }, 414 { .compatible = "mediatek,mt8192-i2c", .data = &mt8192_compat }, 415 {} 416 }; 417 MODULE_DEVICE_TABLE(of, mtk_i2c_of_match); 418 419 static u16 mtk_i2c_readw(struct mtk_i2c *i2c, enum I2C_REGS_OFFSET reg) 420 { 421 return readw(i2c->base + i2c->dev_comp->regs[reg]); 422 } 423 424 static void mtk_i2c_writew(struct mtk_i2c *i2c, u16 val, 425 enum I2C_REGS_OFFSET reg) 426 { 427 writew(val, i2c->base + i2c->dev_comp->regs[reg]); 428 } 429 430 static int mtk_i2c_clock_enable(struct mtk_i2c *i2c) 431 { 432 int ret; 433 434 ret = clk_prepare_enable(i2c->clk_dma); 435 if (ret) 436 return ret; 437 438 ret = clk_prepare_enable(i2c->clk_main); 439 if (ret) 440 goto err_main; 441 442 if (i2c->have_pmic) { 443 ret = clk_prepare_enable(i2c->clk_pmic); 444 if (ret) 445 goto err_pmic; 446 } 447 448 if (i2c->clk_arb) { 449 ret = clk_prepare_enable(i2c->clk_arb); 450 if (ret) 451 goto err_arb; 452 } 453 454 return 0; 455 456 err_arb: 457 if (i2c->have_pmic) 458 clk_disable_unprepare(i2c->clk_pmic); 459 err_pmic: 460 clk_disable_unprepare(i2c->clk_main); 461 err_main: 462 clk_disable_unprepare(i2c->clk_dma); 463 464 return ret; 465 } 466 467 static void mtk_i2c_clock_disable(struct mtk_i2c *i2c) 468 { 469 if (i2c->clk_arb) 470 clk_disable_unprepare(i2c->clk_arb); 471 472 if (i2c->have_pmic) 473 clk_disable_unprepare(i2c->clk_pmic); 474 475 clk_disable_unprepare(i2c->clk_main); 476 clk_disable_unprepare(i2c->clk_dma); 477 } 478 479 static void mtk_i2c_init_hw(struct mtk_i2c *i2c) 480 { 481 u16 control_reg; 482 u16 intr_stat_reg; 483 484 mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_START); 485 intr_stat_reg = mtk_i2c_readw(i2c, OFFSET_INTR_STAT); 486 mtk_i2c_writew(i2c, intr_stat_reg, OFFSET_INTR_STAT); 487 488 if (i2c->dev_comp->apdma_sync) { 489 writel(I2C_DMA_WARM_RST, i2c->pdmabase + OFFSET_RST); 490 udelay(10); 491 writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); 492 udelay(10); 493 writel(I2C_DMA_HANDSHAKE_RST | I2C_DMA_HARD_RST, 494 i2c->pdmabase + OFFSET_RST); 495 mtk_i2c_writew(i2c, I2C_HANDSHAKE_RST | I2C_SOFT_RST, 496 OFFSET_SOFTRESET); 497 udelay(10); 498 writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); 499 mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_SOFTRESET); 500 } else { 501 writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST); 502 udelay(50); 503 writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); 504 mtk_i2c_writew(i2c, I2C_SOFT_RST, OFFSET_SOFTRESET); 505 } 506 507 /* Set ioconfig */ 508 if (i2c->use_push_pull) 509 mtk_i2c_writew(i2c, I2C_IO_CONFIG_PUSH_PULL, OFFSET_IO_CONFIG); 510 else 511 mtk_i2c_writew(i2c, I2C_IO_CONFIG_OPEN_DRAIN, OFFSET_IO_CONFIG); 512 513 if (i2c->dev_comp->dcm) 514 mtk_i2c_writew(i2c, I2C_DCM_DISABLE, OFFSET_DCM_EN); 515 516 mtk_i2c_writew(i2c, i2c->timing_reg, OFFSET_TIMING); 517 mtk_i2c_writew(i2c, i2c->high_speed_reg, OFFSET_HS); 518 if (i2c->dev_comp->ltiming_adjust) 519 mtk_i2c_writew(i2c, i2c->ltiming_reg, OFFSET_LTIMING); 520 521 if (i2c->dev_comp->timing_adjust) { 522 mtk_i2c_writew(i2c, i2c->ac_timing.ext, OFFSET_EXT_CONF); 523 mtk_i2c_writew(i2c, i2c->ac_timing.inter_clk_div, 524 OFFSET_CLOCK_DIV); 525 mtk_i2c_writew(i2c, I2C_SCL_MIS_COMP_VALUE, 526 OFFSET_SCL_MIS_COMP_POINT); 527 mtk_i2c_writew(i2c, i2c->ac_timing.sda_timing, 528 OFFSET_SDA_TIMING); 529 530 if (i2c->dev_comp->ltiming_adjust) { 531 mtk_i2c_writew(i2c, i2c->ac_timing.htiming, 532 OFFSET_TIMING); 533 mtk_i2c_writew(i2c, i2c->ac_timing.hs, OFFSET_HS); 534 mtk_i2c_writew(i2c, i2c->ac_timing.ltiming, 535 OFFSET_LTIMING); 536 } else { 537 mtk_i2c_writew(i2c, i2c->ac_timing.scl_hl_ratio, 538 OFFSET_SCL_HIGH_LOW_RATIO); 539 mtk_i2c_writew(i2c, i2c->ac_timing.hs_scl_hl_ratio, 540 OFFSET_HS_SCL_HIGH_LOW_RATIO); 541 mtk_i2c_writew(i2c, i2c->ac_timing.sta_stop, 542 OFFSET_STA_STO_AC_TIMING); 543 mtk_i2c_writew(i2c, i2c->ac_timing.hs_sta_stop, 544 OFFSET_HS_STA_STO_AC_TIMING); 545 } 546 } 547 548 /* If use i2c pin from PMIC mt6397 side, need set PATH_DIR first */ 549 if (i2c->have_pmic) 550 mtk_i2c_writew(i2c, I2C_CONTROL_WRAPPER, OFFSET_PATH_DIR); 551 552 control_reg = I2C_CONTROL_ACKERR_DET_EN | 553 I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN; 554 if (i2c->dev_comp->dma_sync) 555 control_reg |= I2C_CONTROL_DMAACK_EN | I2C_CONTROL_ASYNC_MODE; 556 557 mtk_i2c_writew(i2c, control_reg, OFFSET_CONTROL); 558 mtk_i2c_writew(i2c, I2C_DELAY_LEN, OFFSET_DELAY_LEN); 559 } 560 561 static const struct i2c_spec_values *mtk_i2c_get_spec(unsigned int speed) 562 { 563 if (speed <= I2C_MAX_STANDARD_MODE_FREQ) 564 return &standard_mode_spec; 565 else if (speed <= I2C_MAX_FAST_MODE_FREQ) 566 return &fast_mode_spec; 567 else 568 return &fast_mode_plus_spec; 569 } 570 571 static int mtk_i2c_max_step_cnt(unsigned int target_speed) 572 { 573 if (target_speed > I2C_MAX_FAST_MODE_PLUS_FREQ) 574 return MAX_HS_STEP_CNT_DIV; 575 else 576 return MAX_STEP_CNT_DIV; 577 } 578 579 /* 580 * Check and Calculate i2c ac-timing 581 * 582 * Hardware design: 583 * sample_ns = (1000000000 * (sample_cnt + 1)) / clk_src 584 * xxx_cnt_div = spec->min_xxx_ns / sample_ns 585 * 586 * Sample_ns is rounded down for xxx_cnt_div would be greater 587 * than the smallest spec. 588 * The sda_timing is chosen as the middle value between 589 * the largest and smallest. 590 */ 591 static int mtk_i2c_check_ac_timing(struct mtk_i2c *i2c, 592 unsigned int clk_src, 593 unsigned int check_speed, 594 unsigned int step_cnt, 595 unsigned int sample_cnt) 596 { 597 const struct i2c_spec_values *spec; 598 unsigned int su_sta_cnt, low_cnt, high_cnt, max_step_cnt; 599 unsigned int sda_max, sda_min, clk_ns, max_sta_cnt = 0x3f; 600 unsigned int sample_ns = div_u64(1000000000ULL * (sample_cnt + 1), 601 clk_src); 602 603 if (!i2c->dev_comp->timing_adjust) 604 return 0; 605 606 if (i2c->dev_comp->ltiming_adjust) 607 max_sta_cnt = 0x100; 608 609 spec = mtk_i2c_get_spec(check_speed); 610 611 if (i2c->dev_comp->ltiming_adjust) 612 clk_ns = 1000000000 / clk_src; 613 else 614 clk_ns = sample_ns / 2; 615 616 su_sta_cnt = DIV_ROUND_UP(spec->min_su_sta_ns + 617 i2c->timing_info.scl_int_delay_ns, clk_ns); 618 if (su_sta_cnt > max_sta_cnt) 619 return -1; 620 621 low_cnt = DIV_ROUND_UP(spec->min_low_ns, sample_ns); 622 max_step_cnt = mtk_i2c_max_step_cnt(check_speed); 623 if ((2 * step_cnt) > low_cnt && low_cnt < max_step_cnt) { 624 if (low_cnt > step_cnt) { 625 high_cnt = 2 * step_cnt - low_cnt; 626 } else { 627 high_cnt = step_cnt; 628 low_cnt = step_cnt; 629 } 630 } else { 631 return -2; 632 } 633 634 sda_max = spec->max_hd_dat_ns / sample_ns; 635 if (sda_max > low_cnt) 636 sda_max = 0; 637 638 sda_min = DIV_ROUND_UP(spec->min_su_dat_ns, sample_ns); 639 if (sda_min < low_cnt) 640 sda_min = 0; 641 642 if (sda_min > sda_max) 643 return -3; 644 645 if (check_speed > I2C_MAX_FAST_MODE_PLUS_FREQ) { 646 if (i2c->dev_comp->ltiming_adjust) { 647 i2c->ac_timing.hs = I2C_TIME_DEFAULT_VALUE | 648 (sample_cnt << 12) | (high_cnt << 8); 649 i2c->ac_timing.ltiming &= ~GENMASK(15, 9); 650 i2c->ac_timing.ltiming |= (sample_cnt << 12) | 651 (low_cnt << 9); 652 i2c->ac_timing.ext &= ~GENMASK(7, 1); 653 i2c->ac_timing.ext |= (su_sta_cnt << 1) | (1 << 0); 654 } else { 655 i2c->ac_timing.hs_scl_hl_ratio = (1 << 12) | 656 (high_cnt << 6) | low_cnt; 657 i2c->ac_timing.hs_sta_stop = (su_sta_cnt << 8) | 658 su_sta_cnt; 659 } 660 i2c->ac_timing.sda_timing &= ~GENMASK(11, 6); 661 i2c->ac_timing.sda_timing |= (1 << 12) | 662 ((sda_max + sda_min) / 2) << 6; 663 } else { 664 if (i2c->dev_comp->ltiming_adjust) { 665 i2c->ac_timing.htiming = (sample_cnt << 8) | (high_cnt); 666 i2c->ac_timing.ltiming = (sample_cnt << 6) | (low_cnt); 667 i2c->ac_timing.ext = (su_sta_cnt << 8) | (1 << 0); 668 } else { 669 i2c->ac_timing.scl_hl_ratio = (1 << 12) | 670 (high_cnt << 6) | low_cnt; 671 i2c->ac_timing.sta_stop = (su_sta_cnt << 8) | 672 su_sta_cnt; 673 } 674 675 i2c->ac_timing.sda_timing = (1 << 12) | 676 (sda_max + sda_min) / 2; 677 } 678 679 return 0; 680 } 681 682 /* 683 * Calculate i2c port speed 684 * 685 * Hardware design: 686 * i2c_bus_freq = parent_clk / (clock_div * 2 * sample_cnt * step_cnt) 687 * clock_div: fixed in hardware, but may be various in different SoCs 688 * 689 * The calculation want to pick the highest bus frequency that is still 690 * less than or equal to i2c->speed_hz. The calculation try to get 691 * sample_cnt and step_cn 692 */ 693 static int mtk_i2c_calculate_speed(struct mtk_i2c *i2c, unsigned int clk_src, 694 unsigned int target_speed, 695 unsigned int *timing_step_cnt, 696 unsigned int *timing_sample_cnt) 697 { 698 unsigned int step_cnt; 699 unsigned int sample_cnt; 700 unsigned int max_step_cnt; 701 unsigned int base_sample_cnt = MAX_SAMPLE_CNT_DIV; 702 unsigned int base_step_cnt; 703 unsigned int opt_div; 704 unsigned int best_mul; 705 unsigned int cnt_mul; 706 int ret = -EINVAL; 707 708 if (target_speed > I2C_MAX_HIGH_SPEED_MODE_FREQ) 709 target_speed = I2C_MAX_HIGH_SPEED_MODE_FREQ; 710 711 max_step_cnt = mtk_i2c_max_step_cnt(target_speed); 712 base_step_cnt = max_step_cnt; 713 /* Find the best combination */ 714 opt_div = DIV_ROUND_UP(clk_src >> 1, target_speed); 715 best_mul = MAX_SAMPLE_CNT_DIV * max_step_cnt; 716 717 /* Search for the best pair (sample_cnt, step_cnt) with 718 * 0 < sample_cnt < MAX_SAMPLE_CNT_DIV 719 * 0 < step_cnt < max_step_cnt 720 * sample_cnt * step_cnt >= opt_div 721 * optimizing for sample_cnt * step_cnt being minimal 722 */ 723 for (sample_cnt = 1; sample_cnt <= MAX_SAMPLE_CNT_DIV; sample_cnt++) { 724 step_cnt = DIV_ROUND_UP(opt_div, sample_cnt); 725 cnt_mul = step_cnt * sample_cnt; 726 if (step_cnt > max_step_cnt) 727 continue; 728 729 if (cnt_mul < best_mul) { 730 ret = mtk_i2c_check_ac_timing(i2c, clk_src, 731 target_speed, step_cnt - 1, sample_cnt - 1); 732 if (ret) 733 continue; 734 735 best_mul = cnt_mul; 736 base_sample_cnt = sample_cnt; 737 base_step_cnt = step_cnt; 738 if (best_mul == opt_div) 739 break; 740 } 741 } 742 743 if (ret) 744 return -EINVAL; 745 746 sample_cnt = base_sample_cnt; 747 step_cnt = base_step_cnt; 748 749 if ((clk_src / (2 * sample_cnt * step_cnt)) > target_speed) { 750 /* In this case, hardware can't support such 751 * low i2c_bus_freq 752 */ 753 dev_dbg(i2c->dev, "Unsupported speed (%uhz)\n", target_speed); 754 return -EINVAL; 755 } 756 757 *timing_step_cnt = step_cnt - 1; 758 *timing_sample_cnt = sample_cnt - 1; 759 760 return 0; 761 } 762 763 static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk) 764 { 765 unsigned int clk_src; 766 unsigned int step_cnt; 767 unsigned int sample_cnt; 768 unsigned int l_step_cnt; 769 unsigned int l_sample_cnt; 770 unsigned int target_speed; 771 unsigned int clk_div; 772 unsigned int max_clk_div; 773 int ret; 774 775 target_speed = i2c->speed_hz; 776 parent_clk /= i2c->clk_src_div; 777 778 if (i2c->dev_comp->timing_adjust) 779 max_clk_div = MAX_CLOCK_DIV; 780 else 781 max_clk_div = 1; 782 783 for (clk_div = 1; clk_div <= max_clk_div; clk_div++) { 784 clk_src = parent_clk / clk_div; 785 786 if (target_speed > I2C_MAX_FAST_MODE_PLUS_FREQ) { 787 /* Set master code speed register */ 788 ret = mtk_i2c_calculate_speed(i2c, clk_src, 789 I2C_MAX_FAST_MODE_FREQ, 790 &l_step_cnt, 791 &l_sample_cnt); 792 if (ret < 0) 793 continue; 794 795 i2c->timing_reg = (l_sample_cnt << 8) | l_step_cnt; 796 797 /* Set the high speed mode register */ 798 ret = mtk_i2c_calculate_speed(i2c, clk_src, 799 target_speed, &step_cnt, 800 &sample_cnt); 801 if (ret < 0) 802 continue; 803 804 i2c->high_speed_reg = I2C_TIME_DEFAULT_VALUE | 805 (sample_cnt << 12) | (step_cnt << 8); 806 807 if (i2c->dev_comp->ltiming_adjust) 808 i2c->ltiming_reg = 809 (l_sample_cnt << 6) | l_step_cnt | 810 (sample_cnt << 12) | (step_cnt << 9); 811 } else { 812 ret = mtk_i2c_calculate_speed(i2c, clk_src, 813 target_speed, &l_step_cnt, 814 &l_sample_cnt); 815 if (ret < 0) 816 continue; 817 818 i2c->timing_reg = (l_sample_cnt << 8) | l_step_cnt; 819 820 /* Disable the high speed transaction */ 821 i2c->high_speed_reg = I2C_TIME_CLR_VALUE; 822 823 if (i2c->dev_comp->ltiming_adjust) 824 i2c->ltiming_reg = 825 (l_sample_cnt << 6) | l_step_cnt; 826 } 827 828 break; 829 } 830 831 i2c->ac_timing.inter_clk_div = clk_div - 1; 832 833 return 0; 834 } 835 836 static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, 837 int num, int left_num) 838 { 839 u16 addr_reg; 840 u16 start_reg; 841 u16 control_reg; 842 u16 restart_flag = 0; 843 u16 dma_sync = 0; 844 u32 reg_4g_mode; 845 u8 *dma_rd_buf = NULL; 846 u8 *dma_wr_buf = NULL; 847 dma_addr_t rpaddr = 0; 848 dma_addr_t wpaddr = 0; 849 int ret; 850 851 i2c->irq_stat = 0; 852 853 if (i2c->auto_restart) 854 restart_flag = I2C_RS_TRANSFER; 855 856 reinit_completion(&i2c->msg_complete); 857 858 control_reg = mtk_i2c_readw(i2c, OFFSET_CONTROL) & 859 ~(I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS); 860 if ((i2c->speed_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) || (left_num >= 1)) 861 control_reg |= I2C_CONTROL_RS; 862 863 if (i2c->op == I2C_MASTER_WRRD) 864 control_reg |= I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS; 865 866 mtk_i2c_writew(i2c, control_reg, OFFSET_CONTROL); 867 868 addr_reg = i2c_8bit_addr_from_msg(msgs); 869 mtk_i2c_writew(i2c, addr_reg, OFFSET_SLAVE_ADDR); 870 871 /* Clear interrupt status */ 872 mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR | 873 I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_STAT); 874 875 mtk_i2c_writew(i2c, I2C_FIFO_ADDR_CLR, OFFSET_FIFO_ADDR_CLR); 876 877 /* Enable interrupt */ 878 mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR | 879 I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_MASK); 880 881 /* Set transfer and transaction len */ 882 if (i2c->op == I2C_MASTER_WRRD) { 883 if (i2c->dev_comp->aux_len_reg) { 884 mtk_i2c_writew(i2c, msgs->len, OFFSET_TRANSFER_LEN); 885 mtk_i2c_writew(i2c, (msgs + 1)->len, 886 OFFSET_TRANSFER_LEN_AUX); 887 } else { 888 mtk_i2c_writew(i2c, msgs->len | ((msgs + 1)->len) << 8, 889 OFFSET_TRANSFER_LEN); 890 } 891 mtk_i2c_writew(i2c, I2C_WRRD_TRANAC_VALUE, OFFSET_TRANSAC_LEN); 892 } else { 893 mtk_i2c_writew(i2c, msgs->len, OFFSET_TRANSFER_LEN); 894 mtk_i2c_writew(i2c, num, OFFSET_TRANSAC_LEN); 895 } 896 897 if (i2c->dev_comp->apdma_sync) { 898 dma_sync = I2C_DMA_SKIP_CONFIG | I2C_DMA_ASYNC_MODE; 899 if (i2c->op == I2C_MASTER_WRRD) 900 dma_sync |= I2C_DMA_DIR_CHANGE; 901 } 902 903 /* Prepare buffer data to start transfer */ 904 if (i2c->op == I2C_MASTER_RD) { 905 writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG); 906 writel(I2C_DMA_CON_RX | dma_sync, i2c->pdmabase + OFFSET_CON); 907 908 dma_rd_buf = i2c_get_dma_safe_msg_buf(msgs, 1); 909 if (!dma_rd_buf) 910 return -ENOMEM; 911 912 rpaddr = dma_map_single(i2c->dev, dma_rd_buf, 913 msgs->len, DMA_FROM_DEVICE); 914 if (dma_mapping_error(i2c->dev, rpaddr)) { 915 i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, false); 916 917 return -ENOMEM; 918 } 919 920 if (i2c->dev_comp->max_dma_support > 32) { 921 reg_4g_mode = upper_32_bits(rpaddr); 922 writel(reg_4g_mode, i2c->pdmabase + OFFSET_RX_4G_MODE); 923 } 924 925 writel((u32)rpaddr, i2c->pdmabase + OFFSET_RX_MEM_ADDR); 926 writel(msgs->len, i2c->pdmabase + OFFSET_RX_LEN); 927 } else if (i2c->op == I2C_MASTER_WR) { 928 writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG); 929 writel(I2C_DMA_CON_TX | dma_sync, i2c->pdmabase + OFFSET_CON); 930 931 dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 1); 932 if (!dma_wr_buf) 933 return -ENOMEM; 934 935 wpaddr = dma_map_single(i2c->dev, dma_wr_buf, 936 msgs->len, DMA_TO_DEVICE); 937 if (dma_mapping_error(i2c->dev, wpaddr)) { 938 i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); 939 940 return -ENOMEM; 941 } 942 943 if (i2c->dev_comp->max_dma_support > 32) { 944 reg_4g_mode = upper_32_bits(wpaddr); 945 writel(reg_4g_mode, i2c->pdmabase + OFFSET_TX_4G_MODE); 946 } 947 948 writel((u32)wpaddr, i2c->pdmabase + OFFSET_TX_MEM_ADDR); 949 writel(msgs->len, i2c->pdmabase + OFFSET_TX_LEN); 950 } else { 951 writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_INT_FLAG); 952 writel(I2C_DMA_CLR_FLAG | dma_sync, i2c->pdmabase + OFFSET_CON); 953 954 dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 1); 955 if (!dma_wr_buf) 956 return -ENOMEM; 957 958 wpaddr = dma_map_single(i2c->dev, dma_wr_buf, 959 msgs->len, DMA_TO_DEVICE); 960 if (dma_mapping_error(i2c->dev, wpaddr)) { 961 i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); 962 963 return -ENOMEM; 964 } 965 966 dma_rd_buf = i2c_get_dma_safe_msg_buf((msgs + 1), 1); 967 if (!dma_rd_buf) { 968 dma_unmap_single(i2c->dev, wpaddr, 969 msgs->len, DMA_TO_DEVICE); 970 971 i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); 972 973 return -ENOMEM; 974 } 975 976 rpaddr = dma_map_single(i2c->dev, dma_rd_buf, 977 (msgs + 1)->len, 978 DMA_FROM_DEVICE); 979 if (dma_mapping_error(i2c->dev, rpaddr)) { 980 dma_unmap_single(i2c->dev, wpaddr, 981 msgs->len, DMA_TO_DEVICE); 982 983 i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false); 984 i2c_put_dma_safe_msg_buf(dma_rd_buf, (msgs + 1), false); 985 986 return -ENOMEM; 987 } 988 989 if (i2c->dev_comp->max_dma_support > 32) { 990 reg_4g_mode = upper_32_bits(wpaddr); 991 writel(reg_4g_mode, i2c->pdmabase + OFFSET_TX_4G_MODE); 992 993 reg_4g_mode = upper_32_bits(rpaddr); 994 writel(reg_4g_mode, i2c->pdmabase + OFFSET_RX_4G_MODE); 995 } 996 997 writel((u32)wpaddr, i2c->pdmabase + OFFSET_TX_MEM_ADDR); 998 writel((u32)rpaddr, i2c->pdmabase + OFFSET_RX_MEM_ADDR); 999 writel(msgs->len, i2c->pdmabase + OFFSET_TX_LEN); 1000 writel((msgs + 1)->len, i2c->pdmabase + OFFSET_RX_LEN); 1001 } 1002 1003 writel(I2C_DMA_START_EN, i2c->pdmabase + OFFSET_EN); 1004 1005 if (!i2c->auto_restart) { 1006 start_reg = I2C_TRANSAC_START; 1007 } else { 1008 start_reg = I2C_TRANSAC_START | I2C_RS_MUL_TRIG; 1009 if (left_num >= 1) 1010 start_reg |= I2C_RS_MUL_CNFG; 1011 } 1012 mtk_i2c_writew(i2c, start_reg, OFFSET_START); 1013 1014 ret = wait_for_completion_timeout(&i2c->msg_complete, 1015 i2c->adap.timeout); 1016 1017 /* Clear interrupt mask */ 1018 mtk_i2c_writew(i2c, ~(restart_flag | I2C_HS_NACKERR | I2C_ACKERR | 1019 I2C_ARB_LOST | I2C_TRANSAC_COMP), OFFSET_INTR_MASK); 1020 1021 if (i2c->op == I2C_MASTER_WR) { 1022 dma_unmap_single(i2c->dev, wpaddr, 1023 msgs->len, DMA_TO_DEVICE); 1024 1025 i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true); 1026 } else if (i2c->op == I2C_MASTER_RD) { 1027 dma_unmap_single(i2c->dev, rpaddr, 1028 msgs->len, DMA_FROM_DEVICE); 1029 1030 i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, true); 1031 } else { 1032 dma_unmap_single(i2c->dev, wpaddr, msgs->len, 1033 DMA_TO_DEVICE); 1034 dma_unmap_single(i2c->dev, rpaddr, (msgs + 1)->len, 1035 DMA_FROM_DEVICE); 1036 1037 i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true); 1038 i2c_put_dma_safe_msg_buf(dma_rd_buf, (msgs + 1), true); 1039 } 1040 1041 if (ret == 0) { 1042 dev_dbg(i2c->dev, "addr: %x, transfer timeout\n", msgs->addr); 1043 mtk_i2c_init_hw(i2c); 1044 return -ETIMEDOUT; 1045 } 1046 1047 if (i2c->irq_stat & (I2C_HS_NACKERR | I2C_ACKERR)) { 1048 dev_dbg(i2c->dev, "addr: %x, transfer ACK error\n", msgs->addr); 1049 mtk_i2c_init_hw(i2c); 1050 return -ENXIO; 1051 } 1052 1053 return 0; 1054 } 1055 1056 static int mtk_i2c_transfer(struct i2c_adapter *adap, 1057 struct i2c_msg msgs[], int num) 1058 { 1059 int ret; 1060 int left_num = num; 1061 struct mtk_i2c *i2c = i2c_get_adapdata(adap); 1062 1063 ret = mtk_i2c_clock_enable(i2c); 1064 if (ret) 1065 return ret; 1066 1067 i2c->auto_restart = i2c->dev_comp->auto_restart; 1068 1069 /* checking if we can skip restart and optimize using WRRD mode */ 1070 if (i2c->auto_restart && num == 2) { 1071 if (!(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD) && 1072 msgs[0].addr == msgs[1].addr) { 1073 i2c->auto_restart = 0; 1074 } 1075 } 1076 1077 if (i2c->auto_restart && num >= 2 && 1078 i2c->speed_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) 1079 /* ignore the first restart irq after the master code, 1080 * otherwise the first transfer will be discarded. 1081 */ 1082 i2c->ignore_restart_irq = true; 1083 else 1084 i2c->ignore_restart_irq = false; 1085 1086 while (left_num--) { 1087 if (!msgs->buf) { 1088 dev_dbg(i2c->dev, "data buffer is NULL.\n"); 1089 ret = -EINVAL; 1090 goto err_exit; 1091 } 1092 1093 if (msgs->flags & I2C_M_RD) 1094 i2c->op = I2C_MASTER_RD; 1095 else 1096 i2c->op = I2C_MASTER_WR; 1097 1098 if (!i2c->auto_restart) { 1099 if (num > 1) { 1100 /* combined two messages into one transaction */ 1101 i2c->op = I2C_MASTER_WRRD; 1102 left_num--; 1103 } 1104 } 1105 1106 /* always use DMA mode. */ 1107 ret = mtk_i2c_do_transfer(i2c, msgs, num, left_num); 1108 if (ret < 0) 1109 goto err_exit; 1110 1111 msgs++; 1112 } 1113 /* the return value is number of executed messages */ 1114 ret = num; 1115 1116 err_exit: 1117 mtk_i2c_clock_disable(i2c); 1118 return ret; 1119 } 1120 1121 static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id) 1122 { 1123 struct mtk_i2c *i2c = dev_id; 1124 u16 restart_flag = 0; 1125 u16 intr_stat; 1126 1127 if (i2c->auto_restart) 1128 restart_flag = I2C_RS_TRANSFER; 1129 1130 intr_stat = mtk_i2c_readw(i2c, OFFSET_INTR_STAT); 1131 mtk_i2c_writew(i2c, intr_stat, OFFSET_INTR_STAT); 1132 1133 /* 1134 * when occurs ack error, i2c controller generate two interrupts 1135 * first is the ack error interrupt, then the complete interrupt 1136 * i2c->irq_stat need keep the two interrupt value. 1137 */ 1138 i2c->irq_stat |= intr_stat; 1139 1140 if (i2c->ignore_restart_irq && (i2c->irq_stat & restart_flag)) { 1141 i2c->ignore_restart_irq = false; 1142 i2c->irq_stat = 0; 1143 mtk_i2c_writew(i2c, I2C_RS_MUL_CNFG | I2C_RS_MUL_TRIG | 1144 I2C_TRANSAC_START, OFFSET_START); 1145 } else { 1146 if (i2c->irq_stat & (I2C_TRANSAC_COMP | restart_flag)) 1147 complete(&i2c->msg_complete); 1148 } 1149 1150 return IRQ_HANDLED; 1151 } 1152 1153 static u32 mtk_i2c_functionality(struct i2c_adapter *adap) 1154 { 1155 if (i2c_check_quirks(adap, I2C_AQ_NO_ZERO_LEN)) 1156 return I2C_FUNC_I2C | 1157 (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); 1158 else 1159 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; 1160 } 1161 1162 static const struct i2c_algorithm mtk_i2c_algorithm = { 1163 .master_xfer = mtk_i2c_transfer, 1164 .functionality = mtk_i2c_functionality, 1165 }; 1166 1167 static int mtk_i2c_parse_dt(struct device_node *np, struct mtk_i2c *i2c) 1168 { 1169 int ret; 1170 1171 ret = of_property_read_u32(np, "clock-frequency", &i2c->speed_hz); 1172 if (ret < 0) 1173 i2c->speed_hz = I2C_MAX_STANDARD_MODE_FREQ; 1174 1175 ret = of_property_read_u32(np, "clock-div", &i2c->clk_src_div); 1176 if (ret < 0) 1177 return ret; 1178 1179 if (i2c->clk_src_div == 0) 1180 return -EINVAL; 1181 1182 i2c->have_pmic = of_property_read_bool(np, "mediatek,have-pmic"); 1183 i2c->use_push_pull = 1184 of_property_read_bool(np, "mediatek,use-push-pull"); 1185 1186 i2c_parse_fw_timings(i2c->dev, &i2c->timing_info, true); 1187 1188 return 0; 1189 } 1190 1191 static int mtk_i2c_probe(struct platform_device *pdev) 1192 { 1193 int ret = 0; 1194 struct mtk_i2c *i2c; 1195 struct clk *clk; 1196 struct resource *res; 1197 int irq; 1198 1199 i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); 1200 if (!i2c) 1201 return -ENOMEM; 1202 1203 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 1204 i2c->base = devm_ioremap_resource(&pdev->dev, res); 1205 if (IS_ERR(i2c->base)) 1206 return PTR_ERR(i2c->base); 1207 1208 res = platform_get_resource(pdev, IORESOURCE_MEM, 1); 1209 i2c->pdmabase = devm_ioremap_resource(&pdev->dev, res); 1210 if (IS_ERR(i2c->pdmabase)) 1211 return PTR_ERR(i2c->pdmabase); 1212 1213 irq = platform_get_irq(pdev, 0); 1214 if (irq <= 0) 1215 return irq; 1216 1217 init_completion(&i2c->msg_complete); 1218 1219 i2c->dev_comp = of_device_get_match_data(&pdev->dev); 1220 i2c->adap.dev.of_node = pdev->dev.of_node; 1221 i2c->dev = &pdev->dev; 1222 i2c->adap.dev.parent = &pdev->dev; 1223 i2c->adap.owner = THIS_MODULE; 1224 i2c->adap.algo = &mtk_i2c_algorithm; 1225 i2c->adap.quirks = i2c->dev_comp->quirks; 1226 i2c->adap.timeout = 2 * HZ; 1227 i2c->adap.retries = 1; 1228 i2c->adap.bus_regulator = devm_regulator_get_optional(&pdev->dev, "vbus"); 1229 if (IS_ERR(i2c->adap.bus_regulator)) { 1230 if (PTR_ERR(i2c->adap.bus_regulator) == -ENODEV) 1231 i2c->adap.bus_regulator = NULL; 1232 else 1233 return PTR_ERR(i2c->adap.bus_regulator); 1234 } 1235 1236 ret = mtk_i2c_parse_dt(pdev->dev.of_node, i2c); 1237 if (ret) 1238 return -EINVAL; 1239 1240 if (i2c->have_pmic && !i2c->dev_comp->pmic_i2c) 1241 return -EINVAL; 1242 1243 i2c->clk_main = devm_clk_get(&pdev->dev, "main"); 1244 if (IS_ERR(i2c->clk_main)) { 1245 dev_err(&pdev->dev, "cannot get main clock\n"); 1246 return PTR_ERR(i2c->clk_main); 1247 } 1248 1249 i2c->clk_dma = devm_clk_get(&pdev->dev, "dma"); 1250 if (IS_ERR(i2c->clk_dma)) { 1251 dev_err(&pdev->dev, "cannot get dma clock\n"); 1252 return PTR_ERR(i2c->clk_dma); 1253 } 1254 1255 i2c->clk_arb = devm_clk_get(&pdev->dev, "arb"); 1256 if (IS_ERR(i2c->clk_arb)) 1257 i2c->clk_arb = NULL; 1258 1259 clk = i2c->clk_main; 1260 if (i2c->have_pmic) { 1261 i2c->clk_pmic = devm_clk_get(&pdev->dev, "pmic"); 1262 if (IS_ERR(i2c->clk_pmic)) { 1263 dev_err(&pdev->dev, "cannot get pmic clock\n"); 1264 return PTR_ERR(i2c->clk_pmic); 1265 } 1266 clk = i2c->clk_pmic; 1267 } 1268 1269 strlcpy(i2c->adap.name, I2C_DRV_NAME, sizeof(i2c->adap.name)); 1270 1271 ret = mtk_i2c_set_speed(i2c, clk_get_rate(clk)); 1272 if (ret) { 1273 dev_err(&pdev->dev, "Failed to set the speed.\n"); 1274 return -EINVAL; 1275 } 1276 1277 if (i2c->dev_comp->max_dma_support > 32) { 1278 ret = dma_set_mask(&pdev->dev, 1279 DMA_BIT_MASK(i2c->dev_comp->max_dma_support)); 1280 if (ret) { 1281 dev_err(&pdev->dev, "dma_set_mask return error.\n"); 1282 return ret; 1283 } 1284 } 1285 1286 ret = mtk_i2c_clock_enable(i2c); 1287 if (ret) { 1288 dev_err(&pdev->dev, "clock enable failed!\n"); 1289 return ret; 1290 } 1291 mtk_i2c_init_hw(i2c); 1292 mtk_i2c_clock_disable(i2c); 1293 1294 ret = devm_request_irq(&pdev->dev, irq, mtk_i2c_irq, 1295 IRQF_NO_SUSPEND | IRQF_TRIGGER_NONE, 1296 dev_name(&pdev->dev), i2c); 1297 if (ret < 0) { 1298 dev_err(&pdev->dev, 1299 "Request I2C IRQ %d fail\n", irq); 1300 return ret; 1301 } 1302 1303 i2c_set_adapdata(&i2c->adap, i2c); 1304 ret = i2c_add_adapter(&i2c->adap); 1305 if (ret) 1306 return ret; 1307 1308 platform_set_drvdata(pdev, i2c); 1309 1310 return 0; 1311 } 1312 1313 static int mtk_i2c_remove(struct platform_device *pdev) 1314 { 1315 struct mtk_i2c *i2c = platform_get_drvdata(pdev); 1316 1317 i2c_del_adapter(&i2c->adap); 1318 1319 return 0; 1320 } 1321 1322 #ifdef CONFIG_PM_SLEEP 1323 static int mtk_i2c_suspend_noirq(struct device *dev) 1324 { 1325 struct mtk_i2c *i2c = dev_get_drvdata(dev); 1326 1327 i2c_mark_adapter_suspended(&i2c->adap); 1328 1329 return 0; 1330 } 1331 1332 static int mtk_i2c_resume_noirq(struct device *dev) 1333 { 1334 int ret; 1335 struct mtk_i2c *i2c = dev_get_drvdata(dev); 1336 1337 ret = mtk_i2c_clock_enable(i2c); 1338 if (ret) { 1339 dev_err(dev, "clock enable failed!\n"); 1340 return ret; 1341 } 1342 1343 mtk_i2c_init_hw(i2c); 1344 1345 mtk_i2c_clock_disable(i2c); 1346 1347 i2c_mark_adapter_resumed(&i2c->adap); 1348 1349 return 0; 1350 } 1351 #endif 1352 1353 static const struct dev_pm_ops mtk_i2c_pm = { 1354 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mtk_i2c_suspend_noirq, 1355 mtk_i2c_resume_noirq) 1356 }; 1357 1358 static struct platform_driver mtk_i2c_driver = { 1359 .probe = mtk_i2c_probe, 1360 .remove = mtk_i2c_remove, 1361 .driver = { 1362 .name = I2C_DRV_NAME, 1363 .pm = &mtk_i2c_pm, 1364 .of_match_table = of_match_ptr(mtk_i2c_of_match), 1365 }, 1366 }; 1367 1368 module_platform_driver(mtk_i2c_driver); 1369 1370 MODULE_LICENSE("GPL v2"); 1371 MODULE_DESCRIPTION("MediaTek I2C Bus Driver"); 1372 MODULE_AUTHOR("Xudong Chen <xudong.chen@mediatek.com>"); 1373