1 /* 2 * (C) Copyright 2015 Google, Inc 3 * 4 * (C) Copyright 2008-2014 Rockchip Electronics 5 * Peter, Software Engineering, <superpeter.cai@gmail.com>. 6 * 7 * SPDX-License-Identifier: GPL-2.0+ 8 */ 9 10 #include <common.h> 11 #include <clk.h> 12 #include <dm.h> 13 #include <errno.h> 14 #include <i2c.h> 15 #include <asm/io.h> 16 #include <asm/arch/clock.h> 17 #include <asm/arch/i2c.h> 18 #include <asm/arch/periph.h> 19 #include <dm/pinctrl.h> 20 #include <linux/sizes.h> 21 22 DECLARE_GLOBAL_DATA_PTR; 23 24 /* i2c timerout */ 25 #define I2C_TIMEOUT_MS 100 26 #define I2C_RETRY_COUNT 3 27 28 /* rk i2c fifo max transfer bytes */ 29 #define RK_I2C_FIFO_SIZE 32 30 31 struct rk_i2c { 32 struct clk clk; 33 struct i2c_regs *regs; 34 unsigned int speed; 35 }; 36 37 static inline void rk_i2c_get_div(int div, int *divh, int *divl) 38 { 39 *divl = div / 2; 40 if (div % 2 == 0) 41 *divh = div / 2; 42 else 43 *divh = DIV_ROUND_UP(div, 2); 44 } 45 46 /* 47 * SCL Divisor = 8 * (CLKDIVL+1 + CLKDIVH+1) 48 * SCL = PCLK / SCLK Divisor 49 * i2c_rate = PCLK 50 */ 51 static void rk_i2c_set_clk(struct rk_i2c *i2c, uint32_t scl_rate) 52 { 53 uint32_t i2c_rate; 54 int div, divl, divh; 55 56 /* First get i2c rate from pclk */ 57 i2c_rate = clk_get_rate(&i2c->clk); 58 59 div = DIV_ROUND_UP(i2c_rate, scl_rate * 8) - 2; 60 divh = 0; 61 divl = 0; 62 if (div >= 0) 63 rk_i2c_get_div(div, &divh, &divl); 64 writel(I2C_CLKDIV_VAL(divl, divh), &i2c->regs->clkdiv); 65 66 debug("rk_i2c_set_clk: i2c rate = %d, scl rate = %d\n", i2c_rate, 67 scl_rate); 68 debug("set i2c clk div = %d, divh = %d, divl = %d\n", div, divh, divl); 69 debug("set clk(I2C_CLKDIV: 0x%08x)\n", readl(&i2c->regs->clkdiv)); 70 } 71 72 static void rk_i2c_show_regs(struct i2c_regs *regs) 73 { 74 #ifdef DEBUG 75 uint i; 76 77 debug("i2c_con: 0x%08x\n", readl(®s->con)); 78 debug("i2c_clkdiv: 0x%08x\n", readl(®s->clkdiv)); 79 debug("i2c_mrxaddr: 0x%08x\n", readl(®s->mrxaddr)); 80 debug("i2c_mrxraddR: 0x%08x\n", readl(®s->mrxraddr)); 81 debug("i2c_mtxcnt: 0x%08x\n", readl(®s->mtxcnt)); 82 debug("i2c_mrxcnt: 0x%08x\n", readl(®s->mrxcnt)); 83 debug("i2c_ien: 0x%08x\n", readl(®s->ien)); 84 debug("i2c_ipd: 0x%08x\n", readl(®s->ipd)); 85 debug("i2c_fcnt: 0x%08x\n", readl(®s->fcnt)); 86 for (i = 0; i < 8; i++) 87 debug("i2c_txdata%d: 0x%08x\n", i, readl(®s->txdata[i])); 88 for (i = 0; i < 8; i++) 89 debug("i2c_rxdata%d: 0x%08x\n", i, readl(®s->rxdata[i])); 90 #endif 91 } 92 93 static int rk_i2c_send_start_bit(struct rk_i2c *i2c) 94 { 95 struct i2c_regs *regs = i2c->regs; 96 ulong start; 97 98 debug("I2c Send Start bit.\n"); 99 writel(I2C_IPD_ALL_CLEAN, ®s->ipd); 100 101 writel(I2C_CON_EN | I2C_CON_START, ®s->con); 102 writel(I2C_STARTIEN, ®s->ien); 103 104 start = get_timer(0); 105 while (1) { 106 if (readl(®s->ipd) & I2C_STARTIPD) { 107 writel(I2C_STARTIPD, ®s->ipd); 108 break; 109 } 110 if (get_timer(start) > I2C_TIMEOUT_MS) { 111 debug("I2C Send Start Bit Timeout\n"); 112 rk_i2c_show_regs(regs); 113 return -ETIMEDOUT; 114 } 115 udelay(1); 116 } 117 118 return 0; 119 } 120 121 static int rk_i2c_send_stop_bit(struct rk_i2c *i2c) 122 { 123 struct i2c_regs *regs = i2c->regs; 124 ulong start; 125 126 debug("I2c Send Stop bit.\n"); 127 writel(I2C_IPD_ALL_CLEAN, ®s->ipd); 128 129 writel(I2C_CON_EN | I2C_CON_STOP, ®s->con); 130 writel(I2C_CON_STOP, ®s->ien); 131 132 start = get_timer(0); 133 while (1) { 134 if (readl(®s->ipd) & I2C_STOPIPD) { 135 writel(I2C_STOPIPD, ®s->ipd); 136 break; 137 } 138 if (get_timer(start) > I2C_TIMEOUT_MS) { 139 debug("I2C Send Start Bit Timeout\n"); 140 rk_i2c_show_regs(regs); 141 return -ETIMEDOUT; 142 } 143 udelay(1); 144 } 145 146 return 0; 147 } 148 149 static inline void rk_i2c_disable(struct rk_i2c *i2c) 150 { 151 writel(0, &i2c->regs->con); 152 } 153 154 static int rk_i2c_read(struct rk_i2c *i2c, uchar chip, uint reg, uint r_len, 155 uchar *buf, uint b_len) 156 { 157 struct i2c_regs *regs = i2c->regs; 158 uchar *pbuf = buf; 159 uint bytes_remain_len = b_len; 160 uint bytes_xferred = 0; 161 uint words_xferred = 0; 162 ulong start; 163 uint con = 0; 164 uint rxdata; 165 uint i, j; 166 int err; 167 bool snd_chunk = false; 168 169 debug("rk_i2c_read: chip = %d, reg = %d, r_len = %d, b_len = %d\n", 170 chip, reg, r_len, b_len); 171 172 err = rk_i2c_send_start_bit(i2c); 173 if (err) 174 return err; 175 176 writel(I2C_MRXADDR_SET(1, chip << 1 | 1), ®s->mrxaddr); 177 if (r_len == 0) { 178 writel(0, ®s->mrxraddr); 179 } else if (r_len < 4) { 180 writel(I2C_MRXRADDR_SET(r_len, reg), ®s->mrxraddr); 181 } else { 182 debug("I2C Read: addr len %d not supported\n", r_len); 183 return -EIO; 184 } 185 186 while (bytes_remain_len) { 187 if (bytes_remain_len > RK_I2C_FIFO_SIZE) { 188 con = I2C_CON_EN; 189 bytes_xferred = 32; 190 } else { 191 /* 192 * The hw can read up to 32 bytes at a time. If we need 193 * more than one chunk, send an ACK after the last byte. 194 */ 195 con = I2C_CON_EN | I2C_CON_LASTACK; 196 bytes_xferred = bytes_remain_len; 197 } 198 words_xferred = DIV_ROUND_UP(bytes_xferred, 4); 199 200 /* 201 * make sure we are in plain RX mode if we read a second chunk 202 */ 203 if (snd_chunk) 204 con |= I2C_CON_MOD(I2C_MODE_RX); 205 else 206 con |= I2C_CON_MOD(I2C_MODE_TRX); 207 208 writel(con, ®s->con); 209 writel(bytes_xferred, ®s->mrxcnt); 210 writel(I2C_MBRFIEN | I2C_NAKRCVIEN, ®s->ien); 211 212 start = get_timer(0); 213 while (1) { 214 if (readl(®s->ipd) & I2C_NAKRCVIPD) { 215 writel(I2C_NAKRCVIPD, ®s->ipd); 216 err = -EREMOTEIO; 217 } 218 if (readl(®s->ipd) & I2C_MBRFIPD) { 219 writel(I2C_MBRFIPD, ®s->ipd); 220 break; 221 } 222 if (get_timer(start) > I2C_TIMEOUT_MS) { 223 debug("I2C Read Data Timeout\n"); 224 err = -ETIMEDOUT; 225 rk_i2c_show_regs(regs); 226 goto i2c_exit; 227 } 228 udelay(1); 229 } 230 231 for (i = 0; i < words_xferred; i++) { 232 rxdata = readl(®s->rxdata[i]); 233 debug("I2c Read RXDATA[%d] = 0x%x\n", i, rxdata); 234 for (j = 0; j < 4; j++) { 235 if ((i * 4 + j) == bytes_xferred) 236 break; 237 *pbuf++ = (rxdata >> (j * 8)) & 0xff; 238 } 239 } 240 241 bytes_remain_len -= bytes_xferred; 242 snd_chunk = true; 243 debug("I2C Read bytes_remain_len %d\n", bytes_remain_len); 244 } 245 246 i2c_exit: 247 rk_i2c_disable(i2c); 248 249 return err; 250 } 251 252 static int rk_i2c_write(struct rk_i2c *i2c, uchar chip, uint reg, uint r_len, 253 uchar *buf, uint b_len) 254 { 255 struct i2c_regs *regs = i2c->regs; 256 int err; 257 uchar *pbuf = buf; 258 uint bytes_remain_len = b_len + r_len + 1; 259 uint bytes_xferred = 0; 260 uint words_xferred = 0; 261 ulong start; 262 uint txdata; 263 uint i, j; 264 265 debug("rk_i2c_write: chip = %d, reg = %d, r_len = %d, b_len = %d\n", 266 chip, reg, r_len, b_len); 267 err = rk_i2c_send_start_bit(i2c); 268 if (err) 269 return err; 270 271 while (bytes_remain_len) { 272 if (bytes_remain_len > RK_I2C_FIFO_SIZE) 273 bytes_xferred = RK_I2C_FIFO_SIZE; 274 else 275 bytes_xferred = bytes_remain_len; 276 words_xferred = DIV_ROUND_UP(bytes_xferred, 4); 277 278 for (i = 0; i < words_xferred; i++) { 279 txdata = 0; 280 for (j = 0; j < 4; j++) { 281 if ((i * 4 + j) == bytes_xferred) 282 break; 283 284 if (i == 0 && j == 0 && pbuf == buf) { 285 txdata |= (chip << 1); 286 } else if (i == 0 && j <= r_len && pbuf == buf) { 287 txdata |= (reg & 288 (0xff << ((j - 1) * 8))) << 8; 289 } else { 290 txdata |= (*pbuf++)<<(j * 8); 291 } 292 } 293 writel(txdata, ®s->txdata[i]); 294 debug("I2c Write TXDATA[%d] = 0x%08x\n", i, txdata); 295 } 296 297 writel(I2C_CON_EN | I2C_CON_MOD(I2C_MODE_TX), ®s->con); 298 writel(bytes_xferred, ®s->mtxcnt); 299 writel(I2C_MBTFIEN | I2C_NAKRCVIEN, ®s->ien); 300 301 start = get_timer(0); 302 while (1) { 303 if (readl(®s->ipd) & I2C_NAKRCVIPD) { 304 writel(I2C_NAKRCVIPD, ®s->ipd); 305 err = -EREMOTEIO; 306 } 307 if (readl(®s->ipd) & I2C_MBTFIPD) { 308 writel(I2C_MBTFIPD, ®s->ipd); 309 break; 310 } 311 if (get_timer(start) > I2C_TIMEOUT_MS) { 312 debug("I2C Write Data Timeout\n"); 313 err = -ETIMEDOUT; 314 rk_i2c_show_regs(regs); 315 goto i2c_exit; 316 } 317 udelay(1); 318 } 319 320 bytes_remain_len -= bytes_xferred; 321 debug("I2C Write bytes_remain_len %d\n", bytes_remain_len); 322 } 323 324 i2c_exit: 325 rk_i2c_disable(i2c); 326 327 return err; 328 } 329 330 static int rockchip_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, 331 int nmsgs) 332 { 333 struct rk_i2c *i2c = dev_get_priv(bus); 334 int ret; 335 336 debug("i2c_xfer: %d messages\n", nmsgs); 337 for (; nmsgs > 0; nmsgs--, msg++) { 338 debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len); 339 if (msg->flags & I2C_M_RD) { 340 ret = rk_i2c_read(i2c, msg->addr, 0, 0, msg->buf, 341 msg->len); 342 } else { 343 ret = rk_i2c_write(i2c, msg->addr, 0, 0, msg->buf, 344 msg->len); 345 } 346 if (ret) { 347 debug("i2c_write: error sending\n"); 348 return -EREMOTEIO; 349 } 350 } 351 352 rk_i2c_send_stop_bit(i2c); 353 rk_i2c_disable(i2c); 354 355 return 0; 356 } 357 358 int rockchip_i2c_set_bus_speed(struct udevice *bus, unsigned int speed) 359 { 360 struct rk_i2c *i2c = dev_get_priv(bus); 361 362 rk_i2c_set_clk(i2c, speed); 363 364 return 0; 365 } 366 367 static int rockchip_i2c_ofdata_to_platdata(struct udevice *bus) 368 { 369 struct rk_i2c *priv = dev_get_priv(bus); 370 int ret; 371 372 ret = clk_get_by_index(bus, 0, &priv->clk); 373 if (ret < 0) { 374 debug("%s: Could not get clock for %s: %d\n", __func__, 375 bus->name, ret); 376 return ret; 377 } 378 379 return 0; 380 } 381 382 static int rockchip_i2c_probe(struct udevice *bus) 383 { 384 struct rk_i2c *priv = dev_get_priv(bus); 385 386 priv->regs = dev_read_addr_ptr(bus); 387 388 return 0; 389 } 390 391 static const struct dm_i2c_ops rockchip_i2c_ops = { 392 .xfer = rockchip_i2c_xfer, 393 .set_bus_speed = rockchip_i2c_set_bus_speed, 394 }; 395 396 static const struct udevice_id rockchip_i2c_ids[] = { 397 { .compatible = "rockchip,rk3066-i2c" }, 398 { .compatible = "rockchip,rk3188-i2c" }, 399 { .compatible = "rockchip,rk3288-i2c" }, 400 { .compatible = "rockchip,rk3328-i2c" }, 401 { .compatible = "rockchip,rk3399-i2c" }, 402 { .compatible = "rockchip,rk3228-i2c" }, 403 { .compatible = "rockchip,rv1108-i2c" }, 404 { } 405 }; 406 407 U_BOOT_DRIVER(i2c_rockchip) = { 408 .name = "i2c_rockchip", 409 .id = UCLASS_I2C, 410 .of_match = rockchip_i2c_ids, 411 .ofdata_to_platdata = rockchip_i2c_ofdata_to_platdata, 412 .probe = rockchip_i2c_probe, 413 .priv_auto_alloc_size = sizeof(struct rk_i2c), 414 .ops = &rockchip_i2c_ops, 415 }; 416