1 /* 2 * Intel CHT Whiskey Cove PMIC I2C Master driver 3 * Copyright (C) 2017 Hans de Goede <hdegoede@redhat.com> 4 * 5 * Based on various non upstream patches to support the CHT Whiskey Cove PMIC: 6 * Copyright (C) 2011 - 2014 Intel Corporation. All rights reserved. 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License version 10 * 2 as published by the Free Software Foundation, or (at your option) 11 * any later version. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 */ 18 19 #include <linux/acpi.h> 20 #include <linux/completion.h> 21 #include <linux/delay.h> 22 #include <linux/i2c.h> 23 #include <linux/interrupt.h> 24 #include <linux/irq.h> 25 #include <linux/irqdomain.h> 26 #include <linux/mfd/intel_soc_pmic.h> 27 #include <linux/module.h> 28 #include <linux/platform_device.h> 29 #include <linux/power/bq24190_charger.h> 30 #include <linux/slab.h> 31 32 #define CHT_WC_I2C_CTRL 0x5e24 33 #define CHT_WC_I2C_CTRL_WR BIT(0) 34 #define CHT_WC_I2C_CTRL_RD BIT(1) 35 #define CHT_WC_I2C_CLIENT_ADDR 0x5e25 36 #define CHT_WC_I2C_REG_OFFSET 0x5e26 37 #define CHT_WC_I2C_WRDATA 0x5e27 38 #define CHT_WC_I2C_RDDATA 0x5e28 39 40 #define CHT_WC_EXTCHGRIRQ 0x6e0a 41 #define CHT_WC_EXTCHGRIRQ_CLIENT_IRQ BIT(0) 42 #define CHT_WC_EXTCHGRIRQ_WRITE_IRQ BIT(1) 43 #define CHT_WC_EXTCHGRIRQ_READ_IRQ BIT(2) 44 #define CHT_WC_EXTCHGRIRQ_NACK_IRQ BIT(3) 45 #define CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK ((u8)GENMASK(3, 1)) 46 #define CHT_WC_EXTCHGRIRQ_MSK 0x6e17 47 48 struct cht_wc_i2c_adap { 49 struct i2c_adapter adapter; 50 wait_queue_head_t wait; 51 struct irq_chip irqchip; 52 struct mutex adap_lock; 53 struct mutex irqchip_lock; 54 struct regmap *regmap; 55 struct irq_domain *irq_domain; 56 struct i2c_client *client; 57 int client_irq; 58 u8 irq_mask; 59 u8 old_irq_mask; 60 int read_data; 61 bool io_error; 62 bool done; 63 }; 64 65 static irqreturn_t cht_wc_i2c_adap_thread_handler(int id, void *data) 66 { 67 struct cht_wc_i2c_adap *adap = data; 68 int ret, reg; 69 70 mutex_lock(&adap->adap_lock); 71 72 /* Read IRQs */ 73 ret = regmap_read(adap->regmap, CHT_WC_EXTCHGRIRQ, ®); 74 if (ret) { 75 dev_err(&adap->adapter.dev, "Error reading extchgrirq reg\n"); 76 mutex_unlock(&adap->adap_lock); 77 return IRQ_NONE; 78 } 79 80 reg &= ~adap->irq_mask; 81 82 /* Reads must be acked after reading the received data. */ 83 ret = regmap_read(adap->regmap, CHT_WC_I2C_RDDATA, &adap->read_data); 84 if (ret) 85 adap->io_error = true; 86 87 /* 88 * Immediately ack IRQs, so that if new IRQs arrives while we're 89 * handling the previous ones our irq will re-trigger when we're done. 90 */ 91 ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ, reg); 92 if (ret) 93 dev_err(&adap->adapter.dev, "Error writing extchgrirq reg\n"); 94 95 if (reg & CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK) { 96 adap->io_error |= !!(reg & CHT_WC_EXTCHGRIRQ_NACK_IRQ); 97 adap->done = true; 98 } 99 100 mutex_unlock(&adap->adap_lock); 101 102 if (reg & CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK) 103 wake_up(&adap->wait); 104 105 /* 106 * Do NOT use handle_nested_irq here, the client irq handler will 107 * likely want to do i2c transfers and the i2c controller uses this 108 * interrupt handler as well, so running the client irq handler from 109 * this thread will cause things to lock up. 110 */ 111 if (reg & CHT_WC_EXTCHGRIRQ_CLIENT_IRQ) { 112 /* 113 * generic_handle_irq expects local IRQs to be disabled 114 * as normally it is called from interrupt context. 115 */ 116 local_irq_disable(); 117 generic_handle_irq(adap->client_irq); 118 local_irq_enable(); 119 } 120 121 return IRQ_HANDLED; 122 } 123 124 static u32 cht_wc_i2c_adap_master_func(struct i2c_adapter *adap) 125 { 126 /* This i2c adapter only supports SMBUS byte transfers */ 127 return I2C_FUNC_SMBUS_BYTE_DATA; 128 } 129 130 static int cht_wc_i2c_adap_smbus_xfer(struct i2c_adapter *_adap, u16 addr, 131 unsigned short flags, char read_write, 132 u8 command, int size, 133 union i2c_smbus_data *data) 134 { 135 struct cht_wc_i2c_adap *adap = i2c_get_adapdata(_adap); 136 int ret; 137 138 mutex_lock(&adap->adap_lock); 139 adap->io_error = false; 140 adap->done = false; 141 mutex_unlock(&adap->adap_lock); 142 143 ret = regmap_write(adap->regmap, CHT_WC_I2C_CLIENT_ADDR, addr); 144 if (ret) 145 return ret; 146 147 if (read_write == I2C_SMBUS_WRITE) { 148 ret = regmap_write(adap->regmap, CHT_WC_I2C_WRDATA, data->byte); 149 if (ret) 150 return ret; 151 } 152 153 ret = regmap_write(adap->regmap, CHT_WC_I2C_REG_OFFSET, command); 154 if (ret) 155 return ret; 156 157 ret = regmap_write(adap->regmap, CHT_WC_I2C_CTRL, 158 (read_write == I2C_SMBUS_WRITE) ? 159 CHT_WC_I2C_CTRL_WR : CHT_WC_I2C_CTRL_RD); 160 if (ret) 161 return ret; 162 163 ret = wait_event_timeout(adap->wait, adap->done, msecs_to_jiffies(30)); 164 if (ret == 0) { 165 /* 166 * The CHT GPIO controller serializes all IRQs, sometimes 167 * causing significant delays, check status manually. 168 */ 169 cht_wc_i2c_adap_thread_handler(0, adap); 170 if (!adap->done) 171 return -ETIMEDOUT; 172 } 173 174 ret = 0; 175 mutex_lock(&adap->adap_lock); 176 if (adap->io_error) 177 ret = -EIO; 178 else if (read_write == I2C_SMBUS_READ) 179 data->byte = adap->read_data; 180 mutex_unlock(&adap->adap_lock); 181 182 return ret; 183 } 184 185 static const struct i2c_algorithm cht_wc_i2c_adap_algo = { 186 .functionality = cht_wc_i2c_adap_master_func, 187 .smbus_xfer = cht_wc_i2c_adap_smbus_xfer, 188 }; 189 190 /**** irqchip for the client connected to the extchgr i2c adapter ****/ 191 static void cht_wc_i2c_irq_lock(struct irq_data *data) 192 { 193 struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); 194 195 mutex_lock(&adap->irqchip_lock); 196 } 197 198 static void cht_wc_i2c_irq_sync_unlock(struct irq_data *data) 199 { 200 struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); 201 int ret; 202 203 if (adap->irq_mask != adap->old_irq_mask) { 204 ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ_MSK, 205 adap->irq_mask); 206 if (ret == 0) 207 adap->old_irq_mask = adap->irq_mask; 208 else 209 dev_err(&adap->adapter.dev, "Error writing EXTCHGRIRQ_MSK\n"); 210 } 211 212 mutex_unlock(&adap->irqchip_lock); 213 } 214 215 static void cht_wc_i2c_irq_enable(struct irq_data *data) 216 { 217 struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); 218 219 adap->irq_mask &= ~CHT_WC_EXTCHGRIRQ_CLIENT_IRQ; 220 } 221 222 static void cht_wc_i2c_irq_disable(struct irq_data *data) 223 { 224 struct cht_wc_i2c_adap *adap = irq_data_get_irq_chip_data(data); 225 226 adap->irq_mask |= CHT_WC_EXTCHGRIRQ_CLIENT_IRQ; 227 } 228 229 static const struct irq_chip cht_wc_i2c_irq_chip = { 230 .irq_bus_lock = cht_wc_i2c_irq_lock, 231 .irq_bus_sync_unlock = cht_wc_i2c_irq_sync_unlock, 232 .irq_disable = cht_wc_i2c_irq_disable, 233 .irq_enable = cht_wc_i2c_irq_enable, 234 .name = "cht_wc_ext_chrg_irq_chip", 235 }; 236 237 static const char * const bq24190_suppliers[] = { "fusb302-typec-source" }; 238 239 static const struct property_entry bq24190_props[] = { 240 PROPERTY_ENTRY_STRING_ARRAY("supplied-from", bq24190_suppliers), 241 PROPERTY_ENTRY_BOOL("omit-battery-class"), 242 PROPERTY_ENTRY_BOOL("disable-reset"), 243 { } 244 }; 245 246 static struct regulator_consumer_supply fusb302_consumer = { 247 .supply = "vbus", 248 /* Must match fusb302 dev_name in intel_cht_int33fe.c */ 249 .dev_name = "i2c-fusb302", 250 }; 251 252 static const struct regulator_init_data bq24190_vbus_init_data = { 253 .constraints = { 254 /* The name is used in intel_cht_int33fe.c do not change. */ 255 .name = "cht_wc_usb_typec_vbus", 256 .valid_ops_mask = REGULATOR_CHANGE_STATUS, 257 }, 258 .consumer_supplies = &fusb302_consumer, 259 .num_consumer_supplies = 1, 260 }; 261 262 static struct bq24190_platform_data bq24190_pdata = { 263 .regulator_init_data = &bq24190_vbus_init_data, 264 }; 265 266 static int cht_wc_i2c_adap_i2c_probe(struct platform_device *pdev) 267 { 268 struct intel_soc_pmic *pmic = dev_get_drvdata(pdev->dev.parent); 269 struct cht_wc_i2c_adap *adap; 270 struct i2c_board_info board_info = { 271 .type = "bq24190", 272 .addr = 0x6b, 273 .dev_name = "bq24190", 274 .properties = bq24190_props, 275 .platform_data = &bq24190_pdata, 276 }; 277 int ret, reg, irq; 278 279 irq = platform_get_irq(pdev, 0); 280 if (irq < 0) { 281 dev_err(&pdev->dev, "Error missing irq resource\n"); 282 return -EINVAL; 283 } 284 285 adap = devm_kzalloc(&pdev->dev, sizeof(*adap), GFP_KERNEL); 286 if (!adap) 287 return -ENOMEM; 288 289 init_waitqueue_head(&adap->wait); 290 mutex_init(&adap->adap_lock); 291 mutex_init(&adap->irqchip_lock); 292 adap->irqchip = cht_wc_i2c_irq_chip; 293 adap->regmap = pmic->regmap; 294 adap->adapter.owner = THIS_MODULE; 295 adap->adapter.class = I2C_CLASS_HWMON; 296 adap->adapter.algo = &cht_wc_i2c_adap_algo; 297 strlcpy(adap->adapter.name, "PMIC I2C Adapter", 298 sizeof(adap->adapter.name)); 299 adap->adapter.dev.parent = &pdev->dev; 300 301 /* Clear and activate i2c-adapter interrupts, disable client IRQ */ 302 adap->old_irq_mask = adap->irq_mask = ~CHT_WC_EXTCHGRIRQ_ADAP_IRQMASK; 303 304 ret = regmap_read(adap->regmap, CHT_WC_I2C_RDDATA, ®); 305 if (ret) 306 return ret; 307 308 ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ, ~adap->irq_mask); 309 if (ret) 310 return ret; 311 312 ret = regmap_write(adap->regmap, CHT_WC_EXTCHGRIRQ_MSK, adap->irq_mask); 313 if (ret) 314 return ret; 315 316 /* Alloc and register client IRQ */ 317 adap->irq_domain = irq_domain_add_linear(pdev->dev.of_node, 1, 318 &irq_domain_simple_ops, NULL); 319 if (!adap->irq_domain) 320 return -ENOMEM; 321 322 adap->client_irq = irq_create_mapping(adap->irq_domain, 0); 323 if (!adap->client_irq) { 324 ret = -ENOMEM; 325 goto remove_irq_domain; 326 } 327 328 irq_set_chip_data(adap->client_irq, adap); 329 irq_set_chip_and_handler(adap->client_irq, &adap->irqchip, 330 handle_simple_irq); 331 332 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, 333 cht_wc_i2c_adap_thread_handler, 334 IRQF_ONESHOT, "PMIC I2C Adapter", adap); 335 if (ret) 336 goto remove_irq_domain; 337 338 i2c_set_adapdata(&adap->adapter, adap); 339 ret = i2c_add_adapter(&adap->adapter); 340 if (ret) 341 goto remove_irq_domain; 342 343 /* 344 * Normally the Whiskey Cove PMIC is paired with a TI bq24292i charger, 345 * connected to this i2c bus, and a max17047 fuel-gauge and a fusb302 346 * USB Type-C controller connected to another i2c bus. In this setup 347 * the max17047 and fusb302 devices are enumerated through an INT33FE 348 * ACPI device. If this device is present register an i2c-client for 349 * the TI bq24292i charger. 350 */ 351 if (acpi_dev_present("INT33FE", NULL, -1)) { 352 board_info.irq = adap->client_irq; 353 adap->client = i2c_new_device(&adap->adapter, &board_info); 354 if (!adap->client) { 355 ret = -ENOMEM; 356 goto del_adapter; 357 } 358 } 359 360 platform_set_drvdata(pdev, adap); 361 return 0; 362 363 del_adapter: 364 i2c_del_adapter(&adap->adapter); 365 remove_irq_domain: 366 irq_domain_remove(adap->irq_domain); 367 return ret; 368 } 369 370 static int cht_wc_i2c_adap_i2c_remove(struct platform_device *pdev) 371 { 372 struct cht_wc_i2c_adap *adap = platform_get_drvdata(pdev); 373 374 if (adap->client) 375 i2c_unregister_device(adap->client); 376 i2c_del_adapter(&adap->adapter); 377 irq_domain_remove(adap->irq_domain); 378 379 return 0; 380 } 381 382 static struct platform_device_id cht_wc_i2c_adap_id_table[] = { 383 { .name = "cht_wcove_ext_chgr" }, 384 {}, 385 }; 386 MODULE_DEVICE_TABLE(platform, cht_wc_i2c_adap_id_table); 387 388 static struct platform_driver cht_wc_i2c_adap_driver = { 389 .probe = cht_wc_i2c_adap_i2c_probe, 390 .remove = cht_wc_i2c_adap_i2c_remove, 391 .driver = { 392 .name = "cht_wcove_ext_chgr", 393 }, 394 .id_table = cht_wc_i2c_adap_id_table, 395 }; 396 module_platform_driver(cht_wc_i2c_adap_driver); 397 398 MODULE_DESCRIPTION("Intel CHT Whiskey Cove PMIC I2C Master driver"); 399 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); 400 MODULE_LICENSE("GPL"); 401