linux/drivers/mfd/lochnagar-i2c.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Lochnagar I2C bus interface
   4 *
   5 * Copyright (c) 2012-2018 Cirrus Logic, Inc. and
   6 *                         Cirrus Logic International Semiconductor Ltd.
   7 *
   8 * Author: Charles Keepax <ckeepax@opensource.cirrus.com>
   9 */
  10
  11#include <linux/delay.h>
  12#include <linux/device.h>
  13#include <linux/err.h>
  14#include <linux/gpio/consumer.h>
  15#include <linux/i2c.h>
  16#include <linux/lockdep.h>
  17#include <linux/mfd/core.h>
  18#include <linux/mutex.h>
  19#include <linux/of.h>
  20#include <linux/of_platform.h>
  21#include <linux/regmap.h>
  22
  23#include <linux/mfd/lochnagar.h>
  24#include <linux/mfd/lochnagar1_regs.h>
  25#include <linux/mfd/lochnagar2_regs.h>
  26
  27#define LOCHNAGAR_BOOT_RETRIES          10
  28#define LOCHNAGAR_BOOT_DELAY_MS         350
  29
  30#define LOCHNAGAR_CONFIG_POLL_US        10000
  31
  32static bool lochnagar1_readable_register(struct device *dev, unsigned int reg)
  33{
  34        switch (reg) {
  35        case LOCHNAGAR_SOFTWARE_RESET:
  36        case LOCHNAGAR_FIRMWARE_ID1...LOCHNAGAR_FIRMWARE_ID2:
  37        case LOCHNAGAR1_CDC_AIF1_SEL...LOCHNAGAR1_CDC_AIF3_SEL:
  38        case LOCHNAGAR1_CDC_MCLK1_SEL...LOCHNAGAR1_CDC_MCLK2_SEL:
  39        case LOCHNAGAR1_CDC_AIF_CTRL1...LOCHNAGAR1_CDC_AIF_CTRL2:
  40        case LOCHNAGAR1_EXT_AIF_CTRL:
  41        case LOCHNAGAR1_DSP_AIF1_SEL...LOCHNAGAR1_DSP_AIF2_SEL:
  42        case LOCHNAGAR1_DSP_CLKIN_SEL:
  43        case LOCHNAGAR1_DSP_AIF:
  44        case LOCHNAGAR1_GF_AIF1...LOCHNAGAR1_GF_AIF2:
  45        case LOCHNAGAR1_PSIA_AIF:
  46        case LOCHNAGAR1_PSIA1_SEL...LOCHNAGAR1_PSIA2_SEL:
  47        case LOCHNAGAR1_SPDIF_AIF_SEL:
  48        case LOCHNAGAR1_GF_AIF3_SEL...LOCHNAGAR1_GF_AIF4_SEL:
  49        case LOCHNAGAR1_GF_CLKOUT1_SEL:
  50        case LOCHNAGAR1_GF_AIF1_SEL...LOCHNAGAR1_GF_AIF2_SEL:
  51        case LOCHNAGAR1_GF_GPIO2...LOCHNAGAR1_GF_GPIO7:
  52        case LOCHNAGAR1_RST:
  53        case LOCHNAGAR1_LED1...LOCHNAGAR1_LED2:
  54        case LOCHNAGAR1_I2C_CTRL:
  55                return true;
  56        default:
  57                return false;
  58        }
  59}
  60
  61static const struct regmap_config lochnagar1_i2c_regmap = {
  62        .reg_bits = 8,
  63        .val_bits = 8,
  64        .reg_format_endian = REGMAP_ENDIAN_BIG,
  65        .val_format_endian = REGMAP_ENDIAN_BIG,
  66
  67        .max_register = 0x50,
  68        .readable_reg = lochnagar1_readable_register,
  69
  70        .use_single_read = true,
  71        .use_single_write = true,
  72
  73        .cache_type = REGCACHE_RBTREE,
  74};
  75
  76static const struct reg_sequence lochnagar1_patch[] = {
  77        { 0x40, 0x0083 },
  78        { 0x47, 0x0018 },
  79        { 0x50, 0x0000 },
  80};
  81
  82static bool lochnagar2_readable_register(struct device *dev, unsigned int reg)
  83{
  84        switch (reg) {
  85        case LOCHNAGAR_SOFTWARE_RESET:
  86        case LOCHNAGAR_FIRMWARE_ID1...LOCHNAGAR_FIRMWARE_ID2:
  87        case LOCHNAGAR2_CDC_AIF1_CTRL...LOCHNAGAR2_CDC_AIF3_CTRL:
  88        case LOCHNAGAR2_DSP_AIF1_CTRL...LOCHNAGAR2_DSP_AIF2_CTRL:
  89        case LOCHNAGAR2_PSIA1_CTRL...LOCHNAGAR2_PSIA2_CTRL:
  90        case LOCHNAGAR2_GF_AIF3_CTRL...LOCHNAGAR2_GF_AIF4_CTRL:
  91        case LOCHNAGAR2_GF_AIF1_CTRL...LOCHNAGAR2_GF_AIF2_CTRL:
  92        case LOCHNAGAR2_SPDIF_AIF_CTRL:
  93        case LOCHNAGAR2_USB_AIF1_CTRL...LOCHNAGAR2_USB_AIF2_CTRL:
  94        case LOCHNAGAR2_ADAT_AIF_CTRL:
  95        case LOCHNAGAR2_CDC_MCLK1_CTRL...LOCHNAGAR2_CDC_MCLK2_CTRL:
  96        case LOCHNAGAR2_DSP_CLKIN_CTRL:
  97        case LOCHNAGAR2_PSIA1_MCLK_CTRL...LOCHNAGAR2_PSIA2_MCLK_CTRL:
  98        case LOCHNAGAR2_SPDIF_MCLK_CTRL:
  99        case LOCHNAGAR2_GF_CLKOUT1_CTRL...LOCHNAGAR2_GF_CLKOUT2_CTRL:
 100        case LOCHNAGAR2_ADAT_MCLK_CTRL:
 101        case LOCHNAGAR2_SOUNDCARD_MCLK_CTRL:
 102        case LOCHNAGAR2_GPIO_FPGA_GPIO1...LOCHNAGAR2_GPIO_FPGA_GPIO6:
 103        case LOCHNAGAR2_GPIO_CDC_GPIO1...LOCHNAGAR2_GPIO_CDC_GPIO8:
 104        case LOCHNAGAR2_GPIO_DSP_GPIO1...LOCHNAGAR2_GPIO_DSP_GPIO6:
 105        case LOCHNAGAR2_GPIO_GF_GPIO2...LOCHNAGAR2_GPIO_GF_GPIO7:
 106        case LOCHNAGAR2_GPIO_CDC_AIF1_BCLK...LOCHNAGAR2_GPIO_CDC_AIF3_TXDAT:
 107        case LOCHNAGAR2_GPIO_DSP_AIF1_BCLK...LOCHNAGAR2_GPIO_DSP_AIF2_TXDAT:
 108        case LOCHNAGAR2_GPIO_PSIA1_BCLK...LOCHNAGAR2_GPIO_PSIA2_TXDAT:
 109        case LOCHNAGAR2_GPIO_GF_AIF3_BCLK...LOCHNAGAR2_GPIO_GF_AIF4_TXDAT:
 110        case LOCHNAGAR2_GPIO_GF_AIF1_BCLK...LOCHNAGAR2_GPIO_GF_AIF2_TXDAT:
 111        case LOCHNAGAR2_GPIO_DSP_UART1_RX...LOCHNAGAR2_GPIO_DSP_UART2_TX:
 112        case LOCHNAGAR2_GPIO_GF_UART2_RX...LOCHNAGAR2_GPIO_GF_UART2_TX:
 113        case LOCHNAGAR2_GPIO_USB_UART_RX:
 114        case LOCHNAGAR2_GPIO_CDC_PDMCLK1...LOCHNAGAR2_GPIO_CDC_PDMDAT2:
 115        case LOCHNAGAR2_GPIO_CDC_DMICCLK1...LOCHNAGAR2_GPIO_CDC_DMICDAT4:
 116        case LOCHNAGAR2_GPIO_DSP_DMICCLK1...LOCHNAGAR2_GPIO_DSP_DMICDAT2:
 117        case LOCHNAGAR2_GPIO_I2C2_SCL...LOCHNAGAR2_GPIO_I2C4_SDA:
 118        case LOCHNAGAR2_GPIO_DSP_STANDBY:
 119        case LOCHNAGAR2_GPIO_CDC_MCLK1...LOCHNAGAR2_GPIO_CDC_MCLK2:
 120        case LOCHNAGAR2_GPIO_DSP_CLKIN:
 121        case LOCHNAGAR2_GPIO_PSIA1_MCLK...LOCHNAGAR2_GPIO_PSIA2_MCLK:
 122        case LOCHNAGAR2_GPIO_GF_GPIO1...LOCHNAGAR2_GPIO_GF_GPIO5:
 123        case LOCHNAGAR2_GPIO_DSP_GPIO20:
 124        case LOCHNAGAR2_GPIO_CHANNEL1...LOCHNAGAR2_GPIO_CHANNEL16:
 125        case LOCHNAGAR2_MINICARD_RESETS:
 126        case LOCHNAGAR2_ANALOGUE_PATH_CTRL1...LOCHNAGAR2_ANALOGUE_PATH_CTRL2:
 127        case LOCHNAGAR2_COMMS_CTRL4:
 128        case LOCHNAGAR2_SPDIF_CTRL:
 129        case LOCHNAGAR2_IMON_CTRL1...LOCHNAGAR2_IMON_CTRL4:
 130        case LOCHNAGAR2_IMON_DATA1...LOCHNAGAR2_IMON_DATA2:
 131        case LOCHNAGAR2_POWER_CTRL:
 132        case LOCHNAGAR2_MICVDD_CTRL1:
 133        case LOCHNAGAR2_MICVDD_CTRL2:
 134        case LOCHNAGAR2_VDDCORE_CDC_CTRL1:
 135        case LOCHNAGAR2_VDDCORE_CDC_CTRL2:
 136        case LOCHNAGAR2_SOUNDCARD_AIF_CTRL:
 137                return true;
 138        default:
 139                return false;
 140        }
 141}
 142
 143static bool lochnagar2_volatile_register(struct device *dev, unsigned int reg)
 144{
 145        switch (reg) {
 146        case LOCHNAGAR2_GPIO_CHANNEL1...LOCHNAGAR2_GPIO_CHANNEL16:
 147        case LOCHNAGAR2_ANALOGUE_PATH_CTRL1:
 148        case LOCHNAGAR2_IMON_CTRL3...LOCHNAGAR2_IMON_CTRL4:
 149        case LOCHNAGAR2_IMON_DATA1...LOCHNAGAR2_IMON_DATA2:
 150                return true;
 151        default:
 152                return false;
 153        }
 154}
 155
 156static const struct regmap_config lochnagar2_i2c_regmap = {
 157        .reg_bits = 16,
 158        .val_bits = 16,
 159        .reg_format_endian = REGMAP_ENDIAN_BIG,
 160        .val_format_endian = REGMAP_ENDIAN_BIG,
 161
 162        .max_register = 0x1F1F,
 163        .readable_reg = lochnagar2_readable_register,
 164        .volatile_reg = lochnagar2_volatile_register,
 165
 166        .cache_type = REGCACHE_RBTREE,
 167};
 168
 169static const struct reg_sequence lochnagar2_patch[] = {
 170        { 0x00EE, 0x0000 },
 171};
 172
 173struct lochnagar_config {
 174        int id;
 175        const char * const name;
 176        enum lochnagar_type type;
 177        const struct regmap_config *regmap;
 178        const struct reg_sequence *patch;
 179        int npatch;
 180};
 181
 182static struct lochnagar_config lochnagar_configs[] = {
 183        {
 184                .id = 0x50,
 185                .name = "lochnagar1",
 186                .type = LOCHNAGAR1,
 187                .regmap = &lochnagar1_i2c_regmap,
 188                .patch = lochnagar1_patch,
 189                .npatch = ARRAY_SIZE(lochnagar1_patch),
 190        },
 191        {
 192                .id = 0xCB58,
 193                .name = "lochnagar2",
 194                .type = LOCHNAGAR2,
 195                .regmap = &lochnagar2_i2c_regmap,
 196                .patch = lochnagar2_patch,
 197                .npatch = ARRAY_SIZE(lochnagar2_patch),
 198        },
 199};
 200
 201static const struct of_device_id lochnagar_of_match[] = {
 202        { .compatible = "cirrus,lochnagar1", .data = &lochnagar_configs[0] },
 203        { .compatible = "cirrus,lochnagar2", .data = &lochnagar_configs[1] },
 204        {},
 205};
 206
 207static int lochnagar_wait_for_boot(struct regmap *regmap, unsigned int *id)
 208{
 209        int i, ret;
 210
 211        for (i = 0; i < LOCHNAGAR_BOOT_RETRIES; ++i) {
 212                msleep(LOCHNAGAR_BOOT_DELAY_MS);
 213
 214                /* The reset register will return the device ID when read */
 215                ret = regmap_read(regmap, LOCHNAGAR_SOFTWARE_RESET, id);
 216                if (!ret)
 217                        return ret;
 218        }
 219
 220        return -ETIMEDOUT;
 221}
 222
 223/**
 224 * lochnagar_update_config - Synchronise the boards analogue configuration to
 225 *                           the hardware.
 226 *
 227 * @lochnagar: A pointer to the primary core data structure.
 228 *
 229 * Return: Zero on success or an appropriate negative error code on failure.
 230 */
 231int lochnagar_update_config(struct lochnagar *lochnagar)
 232{
 233        struct regmap *regmap = lochnagar->regmap;
 234        unsigned int done = LOCHNAGAR2_ANALOGUE_PATH_UPDATE_STS_MASK;
 235        int timeout_ms = LOCHNAGAR_BOOT_DELAY_MS * LOCHNAGAR_BOOT_RETRIES;
 236        unsigned int val = 0;
 237        int ret;
 238
 239        lockdep_assert_held(&lochnagar->analogue_config_lock);
 240
 241        if (lochnagar->type != LOCHNAGAR2)
 242                return 0;
 243
 244        /*
 245         * Toggle the ANALOGUE_PATH_UPDATE bit and wait for the device to
 246         * acknowledge that any outstanding changes to the analogue
 247         * configuration have been applied.
 248         */
 249        ret = regmap_write(regmap, LOCHNAGAR2_ANALOGUE_PATH_CTRL1, 0);
 250        if (ret < 0)
 251                return ret;
 252
 253        ret = regmap_write(regmap, LOCHNAGAR2_ANALOGUE_PATH_CTRL1,
 254                           LOCHNAGAR2_ANALOGUE_PATH_UPDATE_MASK);
 255        if (ret < 0)
 256                return ret;
 257
 258        ret = regmap_read_poll_timeout(regmap,
 259                                       LOCHNAGAR2_ANALOGUE_PATH_CTRL1, val,
 260                                       (val & done), LOCHNAGAR_CONFIG_POLL_US,
 261                                       timeout_ms * 1000);
 262        if (ret < 0)
 263                return ret;
 264
 265        return 0;
 266}
 267EXPORT_SYMBOL_GPL(lochnagar_update_config);
 268
 269static int lochnagar_i2c_probe(struct i2c_client *i2c)
 270{
 271        struct device *dev = &i2c->dev;
 272        const struct lochnagar_config *config = NULL;
 273        const struct of_device_id *of_id;
 274        struct lochnagar *lochnagar;
 275        struct gpio_desc *reset, *present;
 276        unsigned int val;
 277        unsigned int firmwareid;
 278        unsigned int devid, rev;
 279        int ret;
 280
 281        lochnagar = devm_kzalloc(dev, sizeof(*lochnagar), GFP_KERNEL);
 282        if (!lochnagar)
 283                return -ENOMEM;
 284
 285        of_id = of_match_device(lochnagar_of_match, dev);
 286        if (!of_id)
 287                return -EINVAL;
 288
 289        config = of_id->data;
 290
 291        lochnagar->dev = dev;
 292        mutex_init(&lochnagar->analogue_config_lock);
 293
 294        dev_set_drvdata(dev, lochnagar);
 295
 296        reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
 297        if (IS_ERR(reset)) {
 298                ret = PTR_ERR(reset);
 299                dev_err(dev, "Failed to get reset GPIO: %d\n", ret);
 300                return ret;
 301        }
 302
 303        present = devm_gpiod_get_optional(dev, "present", GPIOD_OUT_HIGH);
 304        if (IS_ERR(present)) {
 305                ret = PTR_ERR(present);
 306                dev_err(dev, "Failed to get present GPIO: %d\n", ret);
 307                return ret;
 308        }
 309
 310        /* Leave the Lochnagar in reset for a reasonable amount of time */
 311        msleep(20);
 312
 313        /* Bring Lochnagar out of reset */
 314        gpiod_set_value_cansleep(reset, 1);
 315
 316        /* Identify Lochnagar */
 317        lochnagar->type = config->type;
 318
 319        lochnagar->regmap = devm_regmap_init_i2c(i2c, config->regmap);
 320        if (IS_ERR(lochnagar->regmap)) {
 321                ret = PTR_ERR(lochnagar->regmap);
 322                dev_err(dev, "Failed to allocate register map: %d\n", ret);
 323                return ret;
 324        }
 325
 326        /* Wait for Lochnagar to boot */
 327        ret = lochnagar_wait_for_boot(lochnagar->regmap, &val);
 328        if (ret < 0) {
 329                dev_err(dev, "Failed to read device ID: %d\n", ret);
 330                return ret;
 331        }
 332
 333        devid = val & LOCHNAGAR_DEVICE_ID_MASK;
 334        rev = val & LOCHNAGAR_REV_ID_MASK;
 335
 336        if (devid != config->id) {
 337                dev_err(dev,
 338                        "ID does not match %s (expected 0x%x got 0x%x)\n",
 339                        config->name, config->id, devid);
 340                return -ENODEV;
 341        }
 342
 343        /* Identify firmware */
 344        ret = regmap_read(lochnagar->regmap, LOCHNAGAR_FIRMWARE_ID1, &val);
 345        if (ret < 0) {
 346                dev_err(dev, "Failed to read firmware id 1: %d\n", ret);
 347                return ret;
 348        }
 349
 350        firmwareid = val;
 351
 352        ret = regmap_read(lochnagar->regmap, LOCHNAGAR_FIRMWARE_ID2, &val);
 353        if (ret < 0) {
 354                dev_err(dev, "Failed to read firmware id 2: %d\n", ret);
 355                return ret;
 356        }
 357
 358        firmwareid |= (val << config->regmap->val_bits);
 359
 360        dev_info(dev, "Found %s (0x%x) revision %u firmware 0x%.6x\n",
 361                 config->name, devid, rev + 1, firmwareid);
 362
 363        ret = regmap_register_patch(lochnagar->regmap, config->patch,
 364                                    config->npatch);
 365        if (ret < 0) {
 366                dev_err(dev, "Failed to register patch: %d\n", ret);
 367                return ret;
 368        }
 369
 370        ret = devm_of_platform_populate(dev);
 371        if (ret < 0) {
 372                dev_err(dev, "Failed to populate child nodes: %d\n", ret);
 373                return ret;
 374        }
 375
 376        return ret;
 377}
 378
 379static struct i2c_driver lochnagar_i2c_driver = {
 380        .driver = {
 381                .name = "lochnagar",
 382                .of_match_table = of_match_ptr(lochnagar_of_match),
 383                .suppress_bind_attrs = true,
 384        },
 385        .probe_new = lochnagar_i2c_probe,
 386};
 387
 388static int __init lochnagar_i2c_init(void)
 389{
 390        int ret;
 391
 392        ret = i2c_add_driver(&lochnagar_i2c_driver);
 393        if (ret)
 394                pr_err("Failed to register Lochnagar driver: %d\n", ret);
 395
 396        return ret;
 397}
 398subsys_initcall(lochnagar_i2c_init);
 399