Tom Rini | 10e4779 | 2018-05-06 17:58:06 -0400 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0+ |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 2 | /* |
| 3 | * (C) Copyright 2017 STMicroelectronics |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 4 | */ |
| 5 | |
| 6 | #include <common.h> |
| 7 | #include <clk.h> |
| 8 | #include <dm.h> |
| 9 | #include <i2c.h> |
Simon Glass | 0f2af88 | 2020-05-10 11:40:05 -0600 | [diff] [blame] | 10 | #include <log.h> |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 11 | #include <reset.h> |
Simon Glass | 4dcacfc | 2020-05-10 11:40:13 -0600 | [diff] [blame] | 12 | #include <linux/bitops.h> |
Simon Glass | dbd7954 | 2020-05-10 11:40:11 -0600 | [diff] [blame] | 13 | #include <linux/delay.h> |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 14 | |
| 15 | #include <dm/device.h> |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 16 | #include <linux/err.h> |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 17 | #include <linux/io.h> |
| 18 | |
| 19 | /* STM32 I2C registers */ |
| 20 | struct stm32_i2c_regs { |
| 21 | u32 cr1; /* I2C control register 1 */ |
| 22 | u32 cr2; /* I2C control register 2 */ |
| 23 | u32 oar1; /* I2C own address 1 register */ |
| 24 | u32 oar2; /* I2C own address 2 register */ |
| 25 | u32 timingr; /* I2C timing register */ |
| 26 | u32 timeoutr; /* I2C timeout register */ |
| 27 | u32 isr; /* I2C interrupt and status register */ |
| 28 | u32 icr; /* I2C interrupt clear register */ |
| 29 | u32 pecr; /* I2C packet error checking register */ |
| 30 | u32 rxdr; /* I2C receive data register */ |
| 31 | u32 txdr; /* I2C transmit data register */ |
| 32 | }; |
| 33 | |
| 34 | #define STM32_I2C_CR1 0x00 |
| 35 | #define STM32_I2C_CR2 0x04 |
| 36 | #define STM32_I2C_TIMINGR 0x10 |
| 37 | #define STM32_I2C_ISR 0x18 |
| 38 | #define STM32_I2C_ICR 0x1C |
| 39 | #define STM32_I2C_RXDR 0x24 |
| 40 | #define STM32_I2C_TXDR 0x28 |
| 41 | |
| 42 | /* STM32 I2C control 1 */ |
| 43 | #define STM32_I2C_CR1_ANFOFF BIT(12) |
| 44 | #define STM32_I2C_CR1_ERRIE BIT(7) |
| 45 | #define STM32_I2C_CR1_TCIE BIT(6) |
| 46 | #define STM32_I2C_CR1_STOPIE BIT(5) |
| 47 | #define STM32_I2C_CR1_NACKIE BIT(4) |
| 48 | #define STM32_I2C_CR1_ADDRIE BIT(3) |
| 49 | #define STM32_I2C_CR1_RXIE BIT(2) |
| 50 | #define STM32_I2C_CR1_TXIE BIT(1) |
| 51 | #define STM32_I2C_CR1_PE BIT(0) |
| 52 | |
| 53 | /* STM32 I2C control 2 */ |
| 54 | #define STM32_I2C_CR2_AUTOEND BIT(25) |
| 55 | #define STM32_I2C_CR2_RELOAD BIT(24) |
| 56 | #define STM32_I2C_CR2_NBYTES_MASK GENMASK(23, 16) |
| 57 | #define STM32_I2C_CR2_NBYTES(n) ((n & 0xff) << 16) |
| 58 | #define STM32_I2C_CR2_NACK BIT(15) |
| 59 | #define STM32_I2C_CR2_STOP BIT(14) |
| 60 | #define STM32_I2C_CR2_START BIT(13) |
| 61 | #define STM32_I2C_CR2_HEAD10R BIT(12) |
| 62 | #define STM32_I2C_CR2_ADD10 BIT(11) |
| 63 | #define STM32_I2C_CR2_RD_WRN BIT(10) |
| 64 | #define STM32_I2C_CR2_SADD10_MASK GENMASK(9, 0) |
Patrick Delaunay | b13ab6f | 2018-10-29 15:31:55 +0100 | [diff] [blame] | 65 | #define STM32_I2C_CR2_SADD10(n) (n & STM32_I2C_CR2_SADD10_MASK) |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 66 | #define STM32_I2C_CR2_SADD7_MASK GENMASK(7, 1) |
| 67 | #define STM32_I2C_CR2_SADD7(n) ((n & 0x7f) << 1) |
| 68 | #define STM32_I2C_CR2_RESET_MASK (STM32_I2C_CR2_HEAD10R \ |
| 69 | | STM32_I2C_CR2_NBYTES_MASK \ |
| 70 | | STM32_I2C_CR2_SADD7_MASK \ |
| 71 | | STM32_I2C_CR2_RELOAD \ |
| 72 | | STM32_I2C_CR2_RD_WRN) |
| 73 | |
| 74 | /* STM32 I2C Interrupt Status */ |
| 75 | #define STM32_I2C_ISR_BUSY BIT(15) |
| 76 | #define STM32_I2C_ISR_ARLO BIT(9) |
| 77 | #define STM32_I2C_ISR_BERR BIT(8) |
| 78 | #define STM32_I2C_ISR_TCR BIT(7) |
| 79 | #define STM32_I2C_ISR_TC BIT(6) |
| 80 | #define STM32_I2C_ISR_STOPF BIT(5) |
| 81 | #define STM32_I2C_ISR_NACKF BIT(4) |
| 82 | #define STM32_I2C_ISR_ADDR BIT(3) |
| 83 | #define STM32_I2C_ISR_RXNE BIT(2) |
| 84 | #define STM32_I2C_ISR_TXIS BIT(1) |
| 85 | #define STM32_I2C_ISR_TXE BIT(0) |
| 86 | #define STM32_I2C_ISR_ERRORS (STM32_I2C_ISR_BERR \ |
| 87 | | STM32_I2C_ISR_ARLO) |
| 88 | |
| 89 | /* STM32 I2C Interrupt Clear */ |
| 90 | #define STM32_I2C_ICR_ARLOCF BIT(9) |
| 91 | #define STM32_I2C_ICR_BERRCF BIT(8) |
| 92 | #define STM32_I2C_ICR_STOPCF BIT(5) |
| 93 | #define STM32_I2C_ICR_NACKCF BIT(4) |
| 94 | |
| 95 | /* STM32 I2C Timing */ |
| 96 | #define STM32_I2C_TIMINGR_PRESC(n) ((n & 0xf) << 28) |
| 97 | #define STM32_I2C_TIMINGR_SCLDEL(n) ((n & 0xf) << 20) |
| 98 | #define STM32_I2C_TIMINGR_SDADEL(n) ((n & 0xf) << 16) |
| 99 | #define STM32_I2C_TIMINGR_SCLH(n) ((n & 0xff) << 8) |
| 100 | #define STM32_I2C_TIMINGR_SCLL(n) (n & 0xff) |
| 101 | |
| 102 | #define STM32_I2C_MAX_LEN 0xff |
| 103 | |
| 104 | #define STM32_I2C_DNF_DEFAULT 0 |
| 105 | #define STM32_I2C_DNF_MAX 16 |
| 106 | |
| 107 | #define STM32_I2C_ANALOG_FILTER_ENABLE 1 |
| 108 | #define STM32_I2C_ANALOG_FILTER_DELAY_MIN 50 /* ns */ |
| 109 | #define STM32_I2C_ANALOG_FILTER_DELAY_MAX 260 /* ns */ |
| 110 | |
| 111 | #define STM32_I2C_RISE_TIME_DEFAULT 25 /* ns */ |
| 112 | #define STM32_I2C_FALL_TIME_DEFAULT 10 /* ns */ |
| 113 | |
| 114 | #define STM32_PRESC_MAX BIT(4) |
| 115 | #define STM32_SCLDEL_MAX BIT(4) |
| 116 | #define STM32_SDADEL_MAX BIT(4) |
| 117 | #define STM32_SCLH_MAX BIT(8) |
| 118 | #define STM32_SCLL_MAX BIT(8) |
| 119 | |
| 120 | #define STM32_NSEC_PER_SEC 1000000000L |
| 121 | |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 122 | /** |
| 123 | * struct stm32_i2c_spec - private i2c specification timing |
| 124 | * @rate: I2C bus speed (Hz) |
| 125 | * @rate_min: 80% of I2C bus speed (Hz) |
| 126 | * @rate_max: 120% of I2C bus speed (Hz) |
| 127 | * @fall_max: Max fall time of both SDA and SCL signals (ns) |
| 128 | * @rise_max: Max rise time of both SDA and SCL signals (ns) |
| 129 | * @hddat_min: Min data hold time (ns) |
| 130 | * @vddat_max: Max data valid time (ns) |
| 131 | * @sudat_min: Min data setup time (ns) |
| 132 | * @l_min: Min low period of the SCL clock (ns) |
| 133 | * @h_min: Min high period of the SCL clock (ns) |
| 134 | */ |
| 135 | |
| 136 | struct stm32_i2c_spec { |
| 137 | u32 rate; |
| 138 | u32 rate_min; |
| 139 | u32 rate_max; |
| 140 | u32 fall_max; |
| 141 | u32 rise_max; |
| 142 | u32 hddat_min; |
| 143 | u32 vddat_max; |
| 144 | u32 sudat_min; |
| 145 | u32 l_min; |
| 146 | u32 h_min; |
| 147 | }; |
| 148 | |
| 149 | /** |
| 150 | * struct stm32_i2c_setup - private I2C timing setup parameters |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 151 | * @speed_freq: I2C speed frequency (Hz) |
| 152 | * @clock_src: I2C clock source frequency (Hz) |
| 153 | * @rise_time: Rise time (ns) |
| 154 | * @fall_time: Fall time (ns) |
| 155 | * @dnf: Digital filter coefficient (0-16) |
| 156 | * @analog_filter: Analog filter delay (On/Off) |
| 157 | */ |
| 158 | struct stm32_i2c_setup { |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 159 | u32 speed_freq; |
| 160 | u32 clock_src; |
| 161 | u32 rise_time; |
| 162 | u32 fall_time; |
| 163 | u8 dnf; |
| 164 | bool analog_filter; |
| 165 | }; |
| 166 | |
| 167 | /** |
| 168 | * struct stm32_i2c_timings - private I2C output parameters |
| 169 | * @prec: Prescaler value |
| 170 | * @scldel: Data setup time |
| 171 | * @sdadel: Data hold time |
| 172 | * @sclh: SCL high period (master mode) |
| 173 | * @sclh: SCL low period (master mode) |
| 174 | */ |
| 175 | struct stm32_i2c_timings { |
| 176 | struct list_head node; |
| 177 | u8 presc; |
| 178 | u8 scldel; |
| 179 | u8 sdadel; |
| 180 | u8 sclh; |
| 181 | u8 scll; |
| 182 | }; |
| 183 | |
| 184 | struct stm32_i2c_priv { |
| 185 | struct stm32_i2c_regs *regs; |
| 186 | struct clk clk; |
| 187 | struct stm32_i2c_setup *setup; |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 188 | u32 speed; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 189 | }; |
| 190 | |
Patrick Delaunay | bf832e5 | 2018-10-29 15:31:56 +0100 | [diff] [blame] | 191 | static const struct stm32_i2c_spec i2c_specs[] = { |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 192 | /* Standard speed - 100 KHz */ |
Simon Glass | e8e01cc | 2020-01-23 11:48:21 -0700 | [diff] [blame] | 193 | [IC_SPEED_MODE_STANDARD] = { |
| 194 | .rate = I2C_SPEED_STANDARD_RATE, |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 195 | .rate_min = 8000, |
| 196 | .rate_max = 120000, |
| 197 | .fall_max = 300, |
| 198 | .rise_max = 1000, |
| 199 | .hddat_min = 0, |
| 200 | .vddat_max = 3450, |
| 201 | .sudat_min = 250, |
| 202 | .l_min = 4700, |
| 203 | .h_min = 4000, |
| 204 | }, |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 205 | /* Fast speed - 400 KHz */ |
Simon Glass | e8e01cc | 2020-01-23 11:48:21 -0700 | [diff] [blame] | 206 | [IC_SPEED_MODE_FAST] = { |
| 207 | .rate = I2C_SPEED_FAST_RATE, |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 208 | .rate_min = 320000, |
| 209 | .rate_max = 480000, |
| 210 | .fall_max = 300, |
| 211 | .rise_max = 300, |
| 212 | .hddat_min = 0, |
| 213 | .vddat_max = 900, |
| 214 | .sudat_min = 100, |
| 215 | .l_min = 1300, |
| 216 | .h_min = 600, |
| 217 | }, |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 218 | /* Fast Plus Speed - 1 MHz */ |
Simon Glass | e8e01cc | 2020-01-23 11:48:21 -0700 | [diff] [blame] | 219 | [IC_SPEED_MODE_FAST_PLUS] = { |
| 220 | .rate = I2C_SPEED_FAST_PLUS_RATE, |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 221 | .rate_min = 800000, |
| 222 | .rate_max = 1200000, |
| 223 | .fall_max = 100, |
| 224 | .rise_max = 120, |
| 225 | .hddat_min = 0, |
| 226 | .vddat_max = 450, |
| 227 | .sudat_min = 50, |
| 228 | .l_min = 500, |
| 229 | .h_min = 260, |
| 230 | }, |
| 231 | }; |
| 232 | |
Patrick Delaunay | bf832e5 | 2018-10-29 15:31:56 +0100 | [diff] [blame] | 233 | static const struct stm32_i2c_setup stm32f7_setup = { |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 234 | .rise_time = STM32_I2C_RISE_TIME_DEFAULT, |
| 235 | .fall_time = STM32_I2C_FALL_TIME_DEFAULT, |
| 236 | .dnf = STM32_I2C_DNF_DEFAULT, |
| 237 | .analog_filter = STM32_I2C_ANALOG_FILTER_ENABLE, |
| 238 | }; |
| 239 | |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 240 | static int stm32_i2c_check_device_busy(struct stm32_i2c_priv *i2c_priv) |
| 241 | { |
| 242 | struct stm32_i2c_regs *regs = i2c_priv->regs; |
| 243 | u32 status = readl(®s->isr); |
| 244 | |
| 245 | if (status & STM32_I2C_ISR_BUSY) |
| 246 | return -EBUSY; |
| 247 | |
| 248 | return 0; |
| 249 | } |
| 250 | |
| 251 | static void stm32_i2c_message_start(struct stm32_i2c_priv *i2c_priv, |
Patrick Delaunay | b13ab6f | 2018-10-29 15:31:55 +0100 | [diff] [blame] | 252 | struct i2c_msg *msg, bool stop) |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 253 | { |
| 254 | struct stm32_i2c_regs *regs = i2c_priv->regs; |
| 255 | u32 cr2 = readl(®s->cr2); |
| 256 | |
| 257 | /* Set transfer direction */ |
| 258 | cr2 &= ~STM32_I2C_CR2_RD_WRN; |
| 259 | if (msg->flags & I2C_M_RD) |
| 260 | cr2 |= STM32_I2C_CR2_RD_WRN; |
| 261 | |
| 262 | /* Set slave address */ |
| 263 | cr2 &= ~(STM32_I2C_CR2_HEAD10R | STM32_I2C_CR2_ADD10); |
| 264 | if (msg->flags & I2C_M_TEN) { |
| 265 | cr2 &= ~STM32_I2C_CR2_SADD10_MASK; |
| 266 | cr2 |= STM32_I2C_CR2_SADD10(msg->addr); |
| 267 | cr2 |= STM32_I2C_CR2_ADD10; |
| 268 | } else { |
| 269 | cr2 &= ~STM32_I2C_CR2_SADD7_MASK; |
| 270 | cr2 |= STM32_I2C_CR2_SADD7(msg->addr); |
| 271 | } |
| 272 | |
| 273 | /* Set nb bytes to transfer and reload or autoend bits */ |
| 274 | cr2 &= ~(STM32_I2C_CR2_NBYTES_MASK | STM32_I2C_CR2_RELOAD | |
| 275 | STM32_I2C_CR2_AUTOEND); |
| 276 | if (msg->len > STM32_I2C_MAX_LEN) { |
| 277 | cr2 |= STM32_I2C_CR2_NBYTES(STM32_I2C_MAX_LEN); |
| 278 | cr2 |= STM32_I2C_CR2_RELOAD; |
| 279 | } else { |
| 280 | cr2 |= STM32_I2C_CR2_NBYTES(msg->len); |
| 281 | } |
| 282 | |
| 283 | /* Write configurations register */ |
| 284 | writel(cr2, ®s->cr2); |
| 285 | |
| 286 | /* START/ReSTART generation */ |
| 287 | setbits_le32(®s->cr2, STM32_I2C_CR2_START); |
| 288 | } |
| 289 | |
| 290 | /* |
| 291 | * RELOAD mode must be selected if total number of data bytes to be |
| 292 | * sent is greater than MAX_LEN |
| 293 | */ |
| 294 | |
| 295 | static void stm32_i2c_handle_reload(struct stm32_i2c_priv *i2c_priv, |
Patrick Delaunay | b13ab6f | 2018-10-29 15:31:55 +0100 | [diff] [blame] | 296 | struct i2c_msg *msg, bool stop) |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 297 | { |
| 298 | struct stm32_i2c_regs *regs = i2c_priv->regs; |
| 299 | u32 cr2 = readl(®s->cr2); |
| 300 | |
| 301 | cr2 &= ~STM32_I2C_CR2_NBYTES_MASK; |
| 302 | |
| 303 | if (msg->len > STM32_I2C_MAX_LEN) { |
| 304 | cr2 |= STM32_I2C_CR2_NBYTES(STM32_I2C_MAX_LEN); |
| 305 | } else { |
| 306 | cr2 &= ~STM32_I2C_CR2_RELOAD; |
| 307 | cr2 |= STM32_I2C_CR2_NBYTES(msg->len); |
| 308 | } |
| 309 | |
| 310 | writel(cr2, ®s->cr2); |
| 311 | } |
| 312 | |
| 313 | static int stm32_i2c_wait_flags(struct stm32_i2c_priv *i2c_priv, |
Patrick Delaunay | b13ab6f | 2018-10-29 15:31:55 +0100 | [diff] [blame] | 314 | u32 flags, u32 *status) |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 315 | { |
| 316 | struct stm32_i2c_regs *regs = i2c_priv->regs; |
| 317 | u32 time_start = get_timer(0); |
| 318 | |
| 319 | *status = readl(®s->isr); |
| 320 | while (!(*status & flags)) { |
| 321 | if (get_timer(time_start) > CONFIG_SYS_HZ) { |
| 322 | debug("%s: i2c timeout\n", __func__); |
| 323 | return -ETIMEDOUT; |
| 324 | } |
| 325 | |
| 326 | *status = readl(®s->isr); |
| 327 | } |
| 328 | |
| 329 | return 0; |
| 330 | } |
| 331 | |
| 332 | static int stm32_i2c_check_end_of_message(struct stm32_i2c_priv *i2c_priv) |
| 333 | { |
| 334 | struct stm32_i2c_regs *regs = i2c_priv->regs; |
| 335 | u32 mask = STM32_I2C_ISR_ERRORS | STM32_I2C_ISR_NACKF | |
| 336 | STM32_I2C_ISR_STOPF; |
| 337 | u32 status; |
| 338 | int ret; |
| 339 | |
| 340 | ret = stm32_i2c_wait_flags(i2c_priv, mask, &status); |
| 341 | if (ret) |
| 342 | return ret; |
| 343 | |
| 344 | if (status & STM32_I2C_ISR_BERR) { |
| 345 | debug("%s: Bus error\n", __func__); |
| 346 | |
| 347 | /* Clear BERR flag */ |
| 348 | setbits_le32(®s->icr, STM32_I2C_ICR_BERRCF); |
| 349 | |
| 350 | return -EIO; |
| 351 | } |
| 352 | |
| 353 | if (status & STM32_I2C_ISR_ARLO) { |
| 354 | debug("%s: Arbitration lost\n", __func__); |
| 355 | |
| 356 | /* Clear ARLO flag */ |
| 357 | setbits_le32(®s->icr, STM32_I2C_ICR_ARLOCF); |
| 358 | |
| 359 | return -EAGAIN; |
| 360 | } |
| 361 | |
| 362 | if (status & STM32_I2C_ISR_NACKF) { |
| 363 | debug("%s: Receive NACK\n", __func__); |
| 364 | |
| 365 | /* Clear NACK flag */ |
| 366 | setbits_le32(®s->icr, STM32_I2C_ICR_NACKCF); |
| 367 | |
| 368 | /* Wait until STOPF flag is set */ |
| 369 | mask = STM32_I2C_ISR_STOPF; |
| 370 | ret = stm32_i2c_wait_flags(i2c_priv, mask, &status); |
| 371 | if (ret) |
| 372 | return ret; |
| 373 | |
| 374 | ret = -EIO; |
| 375 | } |
| 376 | |
| 377 | if (status & STM32_I2C_ISR_STOPF) { |
| 378 | /* Clear STOP flag */ |
| 379 | setbits_le32(®s->icr, STM32_I2C_ICR_STOPCF); |
| 380 | |
| 381 | /* Clear control register 2 */ |
| 382 | setbits_le32(®s->cr2, STM32_I2C_CR2_RESET_MASK); |
| 383 | } |
| 384 | |
| 385 | return ret; |
| 386 | } |
| 387 | |
| 388 | static int stm32_i2c_message_xfer(struct stm32_i2c_priv *i2c_priv, |
Patrick Delaunay | b13ab6f | 2018-10-29 15:31:55 +0100 | [diff] [blame] | 389 | struct i2c_msg *msg, bool stop) |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 390 | { |
| 391 | struct stm32_i2c_regs *regs = i2c_priv->regs; |
| 392 | u32 status; |
| 393 | u32 mask = msg->flags & I2C_M_RD ? STM32_I2C_ISR_RXNE : |
| 394 | STM32_I2C_ISR_TXIS | STM32_I2C_ISR_NACKF; |
| 395 | int bytes_to_rw = msg->len > STM32_I2C_MAX_LEN ? |
| 396 | STM32_I2C_MAX_LEN : msg->len; |
| 397 | int ret = 0; |
| 398 | |
| 399 | /* Add errors */ |
| 400 | mask |= STM32_I2C_ISR_ERRORS; |
| 401 | |
| 402 | stm32_i2c_message_start(i2c_priv, msg, stop); |
| 403 | |
| 404 | while (msg->len) { |
| 405 | /* |
| 406 | * Wait until TXIS/NACKF/BERR/ARLO flags or |
| 407 | * RXNE/BERR/ARLO flags are set |
| 408 | */ |
| 409 | ret = stm32_i2c_wait_flags(i2c_priv, mask, &status); |
| 410 | if (ret) |
| 411 | break; |
| 412 | |
| 413 | if (status & (STM32_I2C_ISR_NACKF | STM32_I2C_ISR_ERRORS)) |
| 414 | break; |
| 415 | |
| 416 | if (status & STM32_I2C_ISR_RXNE) { |
| 417 | *msg->buf++ = readb(®s->rxdr); |
| 418 | msg->len--; |
| 419 | bytes_to_rw--; |
| 420 | } |
| 421 | |
| 422 | if (status & STM32_I2C_ISR_TXIS) { |
| 423 | writeb(*msg->buf++, ®s->txdr); |
| 424 | msg->len--; |
| 425 | bytes_to_rw--; |
| 426 | } |
| 427 | |
| 428 | if (!bytes_to_rw && msg->len) { |
| 429 | /* Wait until TCR flag is set */ |
| 430 | mask = STM32_I2C_ISR_TCR; |
| 431 | ret = stm32_i2c_wait_flags(i2c_priv, mask, &status); |
| 432 | if (ret) |
| 433 | break; |
| 434 | |
| 435 | bytes_to_rw = msg->len > STM32_I2C_MAX_LEN ? |
| 436 | STM32_I2C_MAX_LEN : msg->len; |
| 437 | mask = msg->flags & I2C_M_RD ? STM32_I2C_ISR_RXNE : |
| 438 | STM32_I2C_ISR_TXIS | STM32_I2C_ISR_NACKF; |
| 439 | |
| 440 | stm32_i2c_handle_reload(i2c_priv, msg, stop); |
| 441 | } else if (!bytes_to_rw) { |
| 442 | /* Wait until TC flag is set */ |
| 443 | mask = STM32_I2C_ISR_TC; |
| 444 | ret = stm32_i2c_wait_flags(i2c_priv, mask, &status); |
| 445 | if (ret) |
| 446 | break; |
| 447 | |
| 448 | if (!stop) |
| 449 | /* Message sent, new message has to be sent */ |
| 450 | return 0; |
| 451 | } |
| 452 | } |
| 453 | |
| 454 | /* End of transfer, send stop condition */ |
| 455 | mask = STM32_I2C_CR2_STOP; |
| 456 | setbits_le32(®s->cr2, mask); |
| 457 | |
| 458 | return stm32_i2c_check_end_of_message(i2c_priv); |
| 459 | } |
| 460 | |
| 461 | static int stm32_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, |
Patrick Delaunay | b13ab6f | 2018-10-29 15:31:55 +0100 | [diff] [blame] | 462 | int nmsgs) |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 463 | { |
| 464 | struct stm32_i2c_priv *i2c_priv = dev_get_priv(bus); |
| 465 | int ret; |
| 466 | |
| 467 | ret = stm32_i2c_check_device_busy(i2c_priv); |
| 468 | if (ret) |
| 469 | return ret; |
| 470 | |
| 471 | for (; nmsgs > 0; nmsgs--, msg++) { |
| 472 | ret = stm32_i2c_message_xfer(i2c_priv, msg, nmsgs == 1); |
| 473 | if (ret) |
| 474 | return ret; |
| 475 | } |
| 476 | |
| 477 | return 0; |
| 478 | } |
| 479 | |
| 480 | static int stm32_i2c_compute_solutions(struct stm32_i2c_setup *setup, |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 481 | const struct stm32_i2c_spec *specs, |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 482 | struct list_head *solutions) |
| 483 | { |
| 484 | struct stm32_i2c_timings *v; |
| 485 | u32 p_prev = STM32_PRESC_MAX; |
| 486 | u32 i2cclk = DIV_ROUND_CLOSEST(STM32_NSEC_PER_SEC, |
| 487 | setup->clock_src); |
| 488 | u32 af_delay_min, af_delay_max; |
| 489 | u16 p, l, a; |
| 490 | int sdadel_min, sdadel_max, scldel_min; |
| 491 | int ret = 0; |
| 492 | |
| 493 | af_delay_min = setup->analog_filter ? |
| 494 | STM32_I2C_ANALOG_FILTER_DELAY_MIN : 0; |
| 495 | af_delay_max = setup->analog_filter ? |
| 496 | STM32_I2C_ANALOG_FILTER_DELAY_MAX : 0; |
| 497 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 498 | sdadel_min = specs->hddat_min + setup->fall_time - |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 499 | af_delay_min - (setup->dnf + 3) * i2cclk; |
| 500 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 501 | sdadel_max = specs->vddat_max - setup->rise_time - |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 502 | af_delay_max - (setup->dnf + 4) * i2cclk; |
| 503 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 504 | scldel_min = setup->rise_time + specs->sudat_min; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 505 | |
| 506 | if (sdadel_min < 0) |
| 507 | sdadel_min = 0; |
| 508 | if (sdadel_max < 0) |
| 509 | sdadel_max = 0; |
| 510 | |
| 511 | debug("%s: SDADEL(min/max): %i/%i, SCLDEL(Min): %i\n", __func__, |
| 512 | sdadel_min, sdadel_max, scldel_min); |
| 513 | |
| 514 | /* Compute possible values for PRESC, SCLDEL and SDADEL */ |
| 515 | for (p = 0; p < STM32_PRESC_MAX; p++) { |
| 516 | for (l = 0; l < STM32_SCLDEL_MAX; l++) { |
Patrick Delaunay | 6f4f912 | 2019-06-21 15:26:47 +0200 | [diff] [blame] | 517 | int scldel = (l + 1) * (p + 1) * i2cclk; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 518 | |
| 519 | if (scldel < scldel_min) |
| 520 | continue; |
| 521 | |
| 522 | for (a = 0; a < STM32_SDADEL_MAX; a++) { |
Patrick Delaunay | 6f4f912 | 2019-06-21 15:26:47 +0200 | [diff] [blame] | 523 | int sdadel = (a * (p + 1) + 1) * i2cclk; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 524 | |
| 525 | if (((sdadel >= sdadel_min) && |
| 526 | (sdadel <= sdadel_max)) && |
| 527 | (p != p_prev)) { |
Patrick Delaunay | 28b10a7 | 2018-03-12 10:46:09 +0100 | [diff] [blame] | 528 | v = calloc(1, sizeof(*v)); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 529 | if (!v) |
| 530 | return -ENOMEM; |
| 531 | |
| 532 | v->presc = p; |
| 533 | v->scldel = l; |
| 534 | v->sdadel = a; |
| 535 | p_prev = p; |
| 536 | |
| 537 | list_add_tail(&v->node, solutions); |
Nicolas Le Bayon | c41d307 | 2019-04-18 17:32:43 +0200 | [diff] [blame] | 538 | break; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 539 | } |
| 540 | } |
Nicolas Le Bayon | c41d307 | 2019-04-18 17:32:43 +0200 | [diff] [blame] | 541 | |
| 542 | if (p_prev == p) |
| 543 | break; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 544 | } |
| 545 | } |
| 546 | |
| 547 | if (list_empty(solutions)) { |
Masahiro Yamada | 81e1042 | 2017-09-16 14:10:41 +0900 | [diff] [blame] | 548 | pr_err("%s: no Prescaler solution\n", __func__); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 549 | ret = -EPERM; |
| 550 | } |
| 551 | |
| 552 | return ret; |
| 553 | } |
| 554 | |
| 555 | static int stm32_i2c_choose_solution(struct stm32_i2c_setup *setup, |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 556 | const struct stm32_i2c_spec *specs, |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 557 | struct list_head *solutions, |
| 558 | struct stm32_i2c_timings *s) |
| 559 | { |
| 560 | struct stm32_i2c_timings *v; |
| 561 | u32 i2cbus = DIV_ROUND_CLOSEST(STM32_NSEC_PER_SEC, |
| 562 | setup->speed_freq); |
| 563 | u32 clk_error_prev = i2cbus; |
| 564 | u32 i2cclk = DIV_ROUND_CLOSEST(STM32_NSEC_PER_SEC, |
| 565 | setup->clock_src); |
| 566 | u32 clk_min, clk_max; |
| 567 | u32 af_delay_min; |
| 568 | u32 dnf_delay; |
| 569 | u32 tsync; |
| 570 | u16 l, h; |
Christophe Kerello | a71376a | 2017-10-17 11:21:32 +0200 | [diff] [blame] | 571 | bool sol_found = false; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 572 | int ret = 0; |
| 573 | |
| 574 | af_delay_min = setup->analog_filter ? |
| 575 | STM32_I2C_ANALOG_FILTER_DELAY_MIN : 0; |
| 576 | dnf_delay = setup->dnf * i2cclk; |
| 577 | |
| 578 | tsync = af_delay_min + dnf_delay + (2 * i2cclk); |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 579 | clk_max = STM32_NSEC_PER_SEC / specs->rate_min; |
| 580 | clk_min = STM32_NSEC_PER_SEC / specs->rate_max; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 581 | |
| 582 | /* |
| 583 | * Among Prescaler possibilities discovered above figures out SCL Low |
| 584 | * and High Period. Provided: |
| 585 | * - SCL Low Period has to be higher than Low Period of the SCL Clock |
| 586 | * defined by I2C Specification. I2C Clock has to be lower than |
| 587 | * (SCL Low Period - Analog/Digital filters) / 4. |
| 588 | * - SCL High Period has to be lower than High Period of the SCL Clock |
| 589 | * defined by I2C Specification |
| 590 | * - I2C Clock has to be lower than SCL High Period |
| 591 | */ |
| 592 | list_for_each_entry(v, solutions, node) { |
| 593 | u32 prescaler = (v->presc + 1) * i2cclk; |
| 594 | |
| 595 | for (l = 0; l < STM32_SCLL_MAX; l++) { |
| 596 | u32 tscl_l = (l + 1) * prescaler + tsync; |
Patrick Delaunay | b13ab6f | 2018-10-29 15:31:55 +0100 | [diff] [blame] | 597 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 598 | if (tscl_l < specs->l_min || |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 599 | (i2cclk >= |
| 600 | ((tscl_l - af_delay_min - dnf_delay) / 4))) { |
| 601 | continue; |
| 602 | } |
| 603 | |
| 604 | for (h = 0; h < STM32_SCLH_MAX; h++) { |
| 605 | u32 tscl_h = (h + 1) * prescaler + tsync; |
| 606 | u32 tscl = tscl_l + tscl_h + |
| 607 | setup->rise_time + setup->fall_time; |
| 608 | |
| 609 | if ((tscl >= clk_min) && (tscl <= clk_max) && |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 610 | (tscl_h >= specs->h_min) && |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 611 | (i2cclk < tscl_h)) { |
Patrick Delaunay | 6f4f912 | 2019-06-21 15:26:47 +0200 | [diff] [blame] | 612 | u32 clk_error; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 613 | |
Patrick Delaunay | 6f4f912 | 2019-06-21 15:26:47 +0200 | [diff] [blame] | 614 | if (tscl > i2cbus) |
| 615 | clk_error = tscl - i2cbus; |
| 616 | else |
| 617 | clk_error = i2cbus - tscl; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 618 | |
| 619 | if (clk_error < clk_error_prev) { |
| 620 | clk_error_prev = clk_error; |
| 621 | v->scll = l; |
| 622 | v->sclh = h; |
Christophe Kerello | a71376a | 2017-10-17 11:21:32 +0200 | [diff] [blame] | 623 | sol_found = true; |
| 624 | memcpy(s, v, sizeof(*s)); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 625 | } |
| 626 | } |
| 627 | } |
| 628 | } |
| 629 | } |
| 630 | |
Christophe Kerello | a71376a | 2017-10-17 11:21:32 +0200 | [diff] [blame] | 631 | if (!sol_found) { |
Masahiro Yamada | 81e1042 | 2017-09-16 14:10:41 +0900 | [diff] [blame] | 632 | pr_err("%s: no solution at all\n", __func__); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 633 | ret = -EPERM; |
| 634 | } |
| 635 | |
| 636 | return ret; |
| 637 | } |
| 638 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 639 | static const struct stm32_i2c_spec *get_specs(u32 rate) |
| 640 | { |
| 641 | unsigned int i; |
| 642 | |
| 643 | for (i = 0; i < ARRAY_SIZE(i2c_specs); i++) |
| 644 | if (rate <= i2c_specs[i].rate) |
| 645 | return &i2c_specs[i]; |
| 646 | |
| 647 | /* NOT REACHED */ |
| 648 | return ERR_PTR(-EINVAL); |
| 649 | } |
| 650 | |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 651 | static int stm32_i2c_compute_timing(struct stm32_i2c_priv *i2c_priv, |
Patrick Delaunay | b13ab6f | 2018-10-29 15:31:55 +0100 | [diff] [blame] | 652 | struct stm32_i2c_setup *setup, |
| 653 | struct stm32_i2c_timings *output) |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 654 | { |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 655 | const struct stm32_i2c_spec *specs; |
Patrice Chotard | c37885d | 2017-10-17 11:21:33 +0200 | [diff] [blame] | 656 | struct stm32_i2c_timings *v, *_v; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 657 | struct list_head solutions; |
| 658 | int ret; |
| 659 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 660 | specs = get_specs(setup->speed_freq); |
| 661 | if (specs == ERR_PTR(-EINVAL)) { |
| 662 | pr_err("%s: speed out of bound {%d}\n", __func__, |
| 663 | setup->speed_freq); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 664 | return -EINVAL; |
| 665 | } |
| 666 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 667 | if (setup->rise_time > specs->rise_max || |
| 668 | setup->fall_time > specs->fall_max) { |
Masahiro Yamada | 81e1042 | 2017-09-16 14:10:41 +0900 | [diff] [blame] | 669 | pr_err("%s :timings out of bound Rise{%d>%d}/Fall{%d>%d}\n", |
Patrick Delaunay | b13ab6f | 2018-10-29 15:31:55 +0100 | [diff] [blame] | 670 | __func__, |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 671 | setup->rise_time, specs->rise_max, |
| 672 | setup->fall_time, specs->fall_max); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 673 | return -EINVAL; |
| 674 | } |
| 675 | |
| 676 | if (setup->dnf > STM32_I2C_DNF_MAX) { |
Masahiro Yamada | 81e1042 | 2017-09-16 14:10:41 +0900 | [diff] [blame] | 677 | pr_err("%s: DNF out of bound %d/%d\n", __func__, |
Patrick Delaunay | b13ab6f | 2018-10-29 15:31:55 +0100 | [diff] [blame] | 678 | setup->dnf, STM32_I2C_DNF_MAX); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 679 | return -EINVAL; |
| 680 | } |
| 681 | |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 682 | INIT_LIST_HEAD(&solutions); |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 683 | ret = stm32_i2c_compute_solutions(setup, specs, &solutions); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 684 | if (ret) |
| 685 | goto exit; |
| 686 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 687 | ret = stm32_i2c_choose_solution(setup, specs, &solutions, output); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 688 | if (ret) |
| 689 | goto exit; |
| 690 | |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 691 | debug("%s: Presc: %i, scldel: %i, sdadel: %i, scll: %i, sclh: %i\n", |
| 692 | __func__, output->presc, |
| 693 | output->scldel, output->sdadel, |
| 694 | output->scll, output->sclh); |
| 695 | |
| 696 | exit: |
| 697 | /* Release list and memory */ |
| 698 | list_for_each_entry_safe(v, _v, &solutions, node) { |
| 699 | list_del(&v->node); |
Patrick Delaunay | 28b10a7 | 2018-03-12 10:46:09 +0100 | [diff] [blame] | 700 | free(v); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 701 | } |
| 702 | |
| 703 | return ret; |
| 704 | } |
| 705 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 706 | static u32 get_lower_rate(u32 rate) |
| 707 | { |
| 708 | int i; |
| 709 | |
| 710 | for (i = ARRAY_SIZE(i2c_specs) - 1; i >= 0; i--) |
| 711 | if (rate > i2c_specs[i].rate) |
| 712 | return i2c_specs[i].rate; |
| 713 | |
| 714 | return i2c_specs[0].rate; |
| 715 | } |
| 716 | |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 717 | static int stm32_i2c_setup_timing(struct stm32_i2c_priv *i2c_priv, |
Patrick Delaunay | b13ab6f | 2018-10-29 15:31:55 +0100 | [diff] [blame] | 718 | struct stm32_i2c_timings *timing) |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 719 | { |
| 720 | struct stm32_i2c_setup *setup = i2c_priv->setup; |
| 721 | int ret = 0; |
| 722 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 723 | setup->speed_freq = i2c_priv->speed; |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 724 | setup->clock_src = clk_get_rate(&i2c_priv->clk); |
| 725 | |
| 726 | if (!setup->clock_src) { |
Masahiro Yamada | 81e1042 | 2017-09-16 14:10:41 +0900 | [diff] [blame] | 727 | pr_err("%s: clock rate is 0\n", __func__); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 728 | return -EINVAL; |
| 729 | } |
| 730 | |
| 731 | do { |
| 732 | ret = stm32_i2c_compute_timing(i2c_priv, setup, timing); |
| 733 | if (ret) { |
| 734 | debug("%s: failed to compute I2C timings.\n", |
| 735 | __func__); |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 736 | if (setup->speed_freq > I2C_SPEED_STANDARD_RATE) { |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 737 | setup->speed_freq = |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 738 | get_lower_rate(setup->speed_freq); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 739 | debug("%s: downgrade I2C Speed Freq to (%i)\n", |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 740 | __func__, setup->speed_freq); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 741 | } else { |
| 742 | break; |
| 743 | } |
| 744 | } |
| 745 | } while (ret); |
| 746 | |
| 747 | if (ret) { |
Masahiro Yamada | 81e1042 | 2017-09-16 14:10:41 +0900 | [diff] [blame] | 748 | pr_err("%s: impossible to compute I2C timings.\n", __func__); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 749 | return ret; |
| 750 | } |
| 751 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 752 | debug("%s: I2C Freq(%i), Clk Source(%i)\n", __func__, |
| 753 | setup->speed_freq, setup->clock_src); |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 754 | debug("%s: I2C Rise(%i) and Fall(%i) Time\n", __func__, |
| 755 | setup->rise_time, setup->fall_time); |
| 756 | debug("%s: I2C Analog Filter(%s), DNF(%i)\n", __func__, |
| 757 | setup->analog_filter ? "On" : "Off", setup->dnf); |
| 758 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 759 | i2c_priv->speed = setup->speed_freq; |
| 760 | |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 761 | return 0; |
| 762 | } |
| 763 | |
| 764 | static int stm32_i2c_hw_config(struct stm32_i2c_priv *i2c_priv) |
| 765 | { |
| 766 | struct stm32_i2c_regs *regs = i2c_priv->regs; |
| 767 | struct stm32_i2c_timings t; |
| 768 | int ret; |
| 769 | u32 timing = 0; |
| 770 | |
| 771 | ret = stm32_i2c_setup_timing(i2c_priv, &t); |
| 772 | if (ret) |
| 773 | return ret; |
| 774 | |
| 775 | /* Disable I2C */ |
| 776 | clrbits_le32(®s->cr1, STM32_I2C_CR1_PE); |
| 777 | |
| 778 | /* Timing settings */ |
| 779 | timing |= STM32_I2C_TIMINGR_PRESC(t.presc); |
| 780 | timing |= STM32_I2C_TIMINGR_SCLDEL(t.scldel); |
| 781 | timing |= STM32_I2C_TIMINGR_SDADEL(t.sdadel); |
| 782 | timing |= STM32_I2C_TIMINGR_SCLH(t.sclh); |
| 783 | timing |= STM32_I2C_TIMINGR_SCLL(t.scll); |
| 784 | writel(timing, ®s->timingr); |
| 785 | |
| 786 | /* Enable I2C */ |
| 787 | if (i2c_priv->setup->analog_filter) |
| 788 | clrbits_le32(®s->cr1, STM32_I2C_CR1_ANFOFF); |
| 789 | else |
| 790 | setbits_le32(®s->cr1, STM32_I2C_CR1_ANFOFF); |
| 791 | setbits_le32(®s->cr1, STM32_I2C_CR1_PE); |
| 792 | |
| 793 | return 0; |
| 794 | } |
| 795 | |
| 796 | static int stm32_i2c_set_bus_speed(struct udevice *bus, unsigned int speed) |
| 797 | { |
| 798 | struct stm32_i2c_priv *i2c_priv = dev_get_priv(bus); |
| 799 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 800 | if (speed > I2C_SPEED_FAST_PLUS_RATE) { |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 801 | debug("%s: Speed %d not supported\n", __func__, speed); |
| 802 | return -EINVAL; |
| 803 | } |
| 804 | |
Alain Volmat | e04600e | 2020-03-06 11:09:14 +0100 | [diff] [blame] | 805 | i2c_priv->speed = speed; |
| 806 | |
Patrice Chotard | ebf442d | 2017-08-09 14:45:27 +0200 | [diff] [blame] | 807 | return stm32_i2c_hw_config(i2c_priv); |
| 808 | } |
| 809 | |
| 810 | static int stm32_i2c_probe(struct udevice *dev) |
| 811 | { |
| 812 | struct stm32_i2c_priv *i2c_priv = dev_get_priv(dev); |
| 813 | struct reset_ctl reset_ctl; |
| 814 | fdt_addr_t addr; |
| 815 | int ret; |
| 816 | |
| 817 | addr = dev_read_addr(dev); |
| 818 | if (addr == FDT_ADDR_T_NONE) |
| 819 | return -EINVAL; |
| 820 | |
| 821 | i2c_priv->regs = (struct stm32_i2c_regs *)addr; |
| 822 | |
| 823 | ret = clk_get_by_index(dev, 0, &i2c_priv->clk); |
| 824 | if (ret) |
| 825 | return ret; |
| 826 | |
| 827 | ret = clk_enable(&i2c_priv->clk); |
| 828 | if (ret) |
| 829 | goto clk_free; |
| 830 | |
| 831 | ret = reset_get_by_index(dev, 0, &reset_ctl); |
| 832 | if (ret) |
| 833 | goto clk_disable; |
| 834 | |
| 835 | reset_assert(&reset_ctl); |
| 836 | udelay(2); |
| 837 | reset_deassert(&reset_ctl); |
| 838 | |
| 839 | return 0; |
| 840 | |
| 841 | clk_disable: |
| 842 | clk_disable(&i2c_priv->clk); |
| 843 | clk_free: |
| 844 | clk_free(&i2c_priv->clk); |
| 845 | |
| 846 | return ret; |
| 847 | } |
| 848 | |
| 849 | static int stm32_ofdata_to_platdata(struct udevice *dev) |
| 850 | { |
| 851 | struct stm32_i2c_priv *i2c_priv = dev_get_priv(dev); |
| 852 | u32 rise_time, fall_time; |
| 853 | |
| 854 | i2c_priv->setup = (struct stm32_i2c_setup *)dev_get_driver_data(dev); |
| 855 | if (!i2c_priv->setup) |
| 856 | return -EINVAL; |
| 857 | |
| 858 | rise_time = dev_read_u32_default(dev, "i2c-scl-rising-time-ns", 0); |
| 859 | if (rise_time) |
| 860 | i2c_priv->setup->rise_time = rise_time; |
| 861 | |
| 862 | fall_time = dev_read_u32_default(dev, "i2c-scl-falling-time-ns", 0); |
| 863 | if (fall_time) |
| 864 | i2c_priv->setup->fall_time = fall_time; |
| 865 | |
| 866 | return 0; |
| 867 | } |
| 868 | |
| 869 | static const struct dm_i2c_ops stm32_i2c_ops = { |
| 870 | .xfer = stm32_i2c_xfer, |
| 871 | .set_bus_speed = stm32_i2c_set_bus_speed, |
| 872 | }; |
| 873 | |
| 874 | static const struct udevice_id stm32_i2c_of_match[] = { |
| 875 | { .compatible = "st,stm32f7-i2c", .data = (ulong)&stm32f7_setup }, |
| 876 | {} |
| 877 | }; |
| 878 | |
| 879 | U_BOOT_DRIVER(stm32f7_i2c) = { |
| 880 | .name = "stm32f7-i2c", |
| 881 | .id = UCLASS_I2C, |
| 882 | .of_match = stm32_i2c_of_match, |
| 883 | .ofdata_to_platdata = stm32_ofdata_to_platdata, |
| 884 | .probe = stm32_i2c_probe, |
| 885 | .priv_auto_alloc_size = sizeof(struct stm32_i2c_priv), |
| 886 | .ops = &stm32_i2c_ops, |
| 887 | }; |