David Collins | 037d648 | 2013-03-14 16:53:33 -0700 | [diff] [blame] | 1 | /* Copyright (c) 2013, The Linux Foundation. All rights reserved. |
| 2 | * |
| 3 | * This program is free software; you can redistribute it and/or modify |
| 4 | * it under the terms of the GNU General Public License version 2 and |
| 5 | * only version 2 as published by the Free Software Foundation. |
| 6 | * |
| 7 | * This program is distributed in the hope that it will be useful, |
| 8 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 9 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 10 | * GNU General Public License for more details. |
| 11 | */ |
| 12 | |
| 13 | #define pr_fmt(fmt) "%s: " fmt, __func__ |
| 14 | |
| 15 | #include <linux/delay.h> |
| 16 | #include <linux/err.h> |
| 17 | #include <linux/init.h> |
| 18 | #include <linux/kernel.h> |
| 19 | #include <linux/module.h> |
| 20 | #include <linux/of.h> |
| 21 | #include <linux/of_device.h> |
| 22 | #include <linux/slab.h> |
| 23 | #include <linux/spmi.h> |
| 24 | #include <linux/regulator/driver.h> |
| 25 | #include <linux/regulator/machine.h> |
| 26 | #include <linux/regulator/of_regulator.h> |
| 27 | |
| 28 | #include "spm.h" |
| 29 | #include "spm-regulator.h" |
| 30 | |
| 31 | #define SPM_REGULATOR_DRIVER_NAME "qcom,spm-regulator" |
| 32 | |
| 33 | struct voltage_range { |
| 34 | int min_uV; |
| 35 | int set_point_min_uV; |
| 36 | int max_uV; |
| 37 | int step_uV; |
| 38 | }; |
| 39 | |
| 40 | /* Properties for FTS2 type QPNP PMIC regulators. */ |
| 41 | |
| 42 | static const struct voltage_range fts2_range0 = {0, 350000, 1275000, 5000}; |
| 43 | static const struct voltage_range fts2_range1 = {0, 700000, 2040000, 10000}; |
| 44 | |
| 45 | /* Specifies the PMIC internal slew rate in uV/us. */ |
| 46 | #define QPNP_FTS2_SLEW_RATE 6000 |
| 47 | |
| 48 | #define QPNP_FTS2_REG_TYPE 0x04 |
| 49 | #define QPNP_FTS2_REG_SUBTYPE 0x05 |
| 50 | #define QPNP_FTS2_REG_VOLTAGE_RANGE 0x40 |
| 51 | #define QPNP_FTS2_REG_VOLTAGE_SETPOINT 0x41 |
| 52 | |
| 53 | #define QPNP_FTS2_TYPE 0x1C |
| 54 | #define QPNP_FTS2_SUBTYPE 0x08 |
| 55 | |
| 56 | struct spm_vreg { |
| 57 | struct regulator_desc rdesc; |
| 58 | struct regulator_dev *rdev; |
| 59 | struct spmi_device *spmi_dev; |
| 60 | const struct voltage_range *range; |
| 61 | int uV; |
| 62 | int last_set_uV; |
| 63 | unsigned vlevel; |
| 64 | unsigned last_set_vlevel; |
| 65 | bool online; |
| 66 | u16 spmi_base_addr; |
| 67 | }; |
| 68 | |
| 69 | static int _spm_regulator_set_voltage(struct regulator_dev *rdev) |
| 70 | { |
| 71 | struct spm_vreg *vreg = rdev_get_drvdata(rdev); |
| 72 | int rc; |
| 73 | |
| 74 | if (vreg->vlevel == vreg->last_set_vlevel) |
| 75 | return 0; |
| 76 | |
| 77 | rc = msm_spm_apcs_set_vdd(vreg->vlevel); |
| 78 | if (rc) { |
| 79 | pr_err("%s: msm_spm_set_vdd failed %d\n", vreg->rdesc.name, rc); |
| 80 | return rc; |
| 81 | } |
| 82 | |
| 83 | if (vreg->uV > vreg->last_set_uV) { |
| 84 | /* Wait for voltage to stabalize. */ |
| 85 | udelay(DIV_ROUND_UP(vreg->uV - vreg->last_set_uV, |
| 86 | QPNP_FTS2_SLEW_RATE)); |
| 87 | } |
| 88 | vreg->last_set_uV = vreg->uV; |
| 89 | vreg->last_set_vlevel = vreg->vlevel; |
| 90 | |
| 91 | return rc; |
| 92 | } |
| 93 | |
| 94 | static int spm_regulator_set_voltage(struct regulator_dev *rdev, int min_uV, |
| 95 | int max_uV, unsigned *selector) |
| 96 | { |
| 97 | struct spm_vreg *vreg = rdev_get_drvdata(rdev); |
| 98 | const struct voltage_range *range = vreg->range; |
| 99 | int uV = min_uV; |
| 100 | unsigned vlevel; |
| 101 | |
| 102 | if (uV < range->set_point_min_uV && max_uV >= range->set_point_min_uV) |
| 103 | uV = range->set_point_min_uV; |
| 104 | |
| 105 | if (uV < range->set_point_min_uV || uV > range->max_uV) { |
| 106 | pr_err("%s: request v=[%d, %d] is outside possible v=[%d, %d]\n", |
| 107 | vreg->rdesc.name, min_uV, max_uV, |
| 108 | range->set_point_min_uV, range->max_uV); |
| 109 | return -EINVAL; |
| 110 | } |
| 111 | |
| 112 | vlevel = DIV_ROUND_UP(uV - range->min_uV, range->step_uV); |
| 113 | uV = vlevel * range->step_uV + range->min_uV; |
| 114 | |
| 115 | if (uV > max_uV) { |
| 116 | pr_err("%s: request v=[%d, %d] cannot be met by any set point\n", |
| 117 | vreg->rdesc.name, min_uV, max_uV); |
| 118 | return -EINVAL; |
| 119 | } |
| 120 | |
| 121 | vreg->vlevel = vlevel; |
| 122 | vreg->uV = uV; |
| 123 | *selector = vlevel - |
| 124 | (vreg->range->set_point_min_uV - vreg->range->min_uV) |
| 125 | / vreg->range->step_uV; |
| 126 | |
| 127 | if (!vreg->online) |
| 128 | return 0; |
| 129 | |
| 130 | return _spm_regulator_set_voltage(rdev); |
| 131 | } |
| 132 | |
| 133 | static int spm_regulator_get_voltage(struct regulator_dev *rdev) |
| 134 | { |
| 135 | struct spm_vreg *vreg = rdev_get_drvdata(rdev); |
| 136 | |
| 137 | return vreg->uV; |
| 138 | } |
| 139 | |
| 140 | static int spm_regulator_list_voltage(struct regulator_dev *rdev, |
| 141 | unsigned selector) |
| 142 | { |
| 143 | struct spm_vreg *vreg = rdev_get_drvdata(rdev); |
| 144 | |
| 145 | if (selector >= vreg->rdesc.n_voltages) |
| 146 | return 0; |
| 147 | |
| 148 | return selector * vreg->range->step_uV + vreg->range->set_point_min_uV; |
| 149 | } |
| 150 | |
| 151 | static int spm_regulator_enable(struct regulator_dev *rdev) |
| 152 | { |
| 153 | struct spm_vreg *vreg = rdev_get_drvdata(rdev); |
| 154 | int rc; |
| 155 | |
| 156 | rc = _spm_regulator_set_voltage(rdev); |
| 157 | |
| 158 | if (!rc) |
| 159 | vreg->online = true; |
| 160 | |
| 161 | return rc; |
| 162 | } |
| 163 | |
| 164 | static int spm_regulator_disable(struct regulator_dev *rdev) |
| 165 | { |
| 166 | struct spm_vreg *vreg = rdev_get_drvdata(rdev); |
| 167 | |
| 168 | vreg->online = false; |
| 169 | |
| 170 | return 0; |
| 171 | } |
| 172 | |
| 173 | static int spm_regulator_is_enabled(struct regulator_dev *rdev) |
| 174 | { |
| 175 | struct spm_vreg *vreg = rdev_get_drvdata(rdev); |
| 176 | |
| 177 | return vreg->online; |
| 178 | } |
| 179 | |
| 180 | static struct regulator_ops spm_regulator_ops = { |
| 181 | .get_voltage = spm_regulator_get_voltage, |
| 182 | .set_voltage = spm_regulator_set_voltage, |
| 183 | .list_voltage = spm_regulator_list_voltage, |
| 184 | .enable = spm_regulator_enable, |
| 185 | .disable = spm_regulator_disable, |
| 186 | .is_enabled = spm_regulator_is_enabled, |
| 187 | }; |
| 188 | |
| 189 | static int qpnp_fts2_check_type(struct spm_vreg *vreg) |
| 190 | { |
| 191 | int rc; |
| 192 | u8 type[2]; |
| 193 | |
| 194 | rc = spmi_ext_register_readl(vreg->spmi_dev->ctrl, vreg->spmi_dev->sid, |
| 195 | vreg->spmi_base_addr + QPNP_FTS2_REG_TYPE, type, 2); |
| 196 | if (rc) { |
| 197 | dev_err(&vreg->spmi_dev->dev, "%s: could not read type register, rc=%d\n", |
| 198 | __func__, rc); |
| 199 | return rc; |
| 200 | } |
| 201 | |
| 202 | if (type[0] != QPNP_FTS2_TYPE || type[1] != QPNP_FTS2_SUBTYPE) { |
| 203 | dev_err(&vreg->spmi_dev->dev, "%s: invalid type=0x%02X or subtype=0x%02X register value\n", |
| 204 | __func__, type[0], type[1]); |
| 205 | return -ENODEV; |
| 206 | } |
| 207 | |
| 208 | return rc; |
| 209 | } |
| 210 | |
| 211 | static int qpnp_fts2_init_range(struct spm_vreg *vreg) |
| 212 | { |
| 213 | int rc; |
| 214 | u8 reg = 0; |
| 215 | |
| 216 | rc = spmi_ext_register_readl(vreg->spmi_dev->ctrl, vreg->spmi_dev->sid, |
| 217 | vreg->spmi_base_addr + QPNP_FTS2_REG_VOLTAGE_RANGE, ®, 1); |
| 218 | if (rc) { |
| 219 | dev_err(&vreg->spmi_dev->dev, "%s: could not read voltage range register, rc=%d\n", |
| 220 | __func__, rc); |
| 221 | return rc; |
| 222 | } |
| 223 | |
| 224 | if (reg == 0x00) { |
| 225 | vreg->range = &fts2_range0; |
| 226 | } else if (reg == 0x01) { |
| 227 | vreg->range = &fts2_range1; |
| 228 | } else { |
| 229 | dev_err(&vreg->spmi_dev->dev, "%s: voltage range=%d is invalid\n", |
| 230 | __func__, reg); |
| 231 | rc = -EINVAL; |
| 232 | } |
| 233 | |
| 234 | return rc; |
| 235 | } |
| 236 | |
| 237 | static int qpnp_fts2_init_voltage(struct spm_vreg *vreg) |
| 238 | { |
| 239 | int rc; |
| 240 | u8 reg = 0; |
| 241 | |
| 242 | rc = spmi_ext_register_readl(vreg->spmi_dev->ctrl, vreg->spmi_dev->sid, |
| 243 | vreg->spmi_base_addr + QPNP_FTS2_REG_VOLTAGE_SETPOINT, ®, 1); |
| 244 | if (rc) { |
| 245 | dev_err(&vreg->spmi_dev->dev, "%s: could not read voltage setpoint register, rc=%d\n", |
| 246 | __func__, rc); |
| 247 | return rc; |
| 248 | } |
| 249 | |
| 250 | vreg->vlevel = reg; |
| 251 | vreg->uV = vreg->vlevel * vreg->range->step_uV + vreg->range->min_uV; |
| 252 | vreg->last_set_uV = vreg->uV; |
| 253 | |
| 254 | return rc; |
| 255 | } |
| 256 | |
| 257 | static int __devinit spm_regulator_probe(struct spmi_device *spmi) |
| 258 | { |
| 259 | struct device_node *node = spmi->dev.of_node; |
| 260 | struct regulator_init_data *init_data; |
| 261 | struct spm_vreg *vreg; |
| 262 | struct resource *res; |
| 263 | int rc; |
| 264 | |
| 265 | if (!node) { |
| 266 | dev_err(&spmi->dev, "%s: device node missing\n", __func__); |
| 267 | return -ENODEV; |
| 268 | } |
| 269 | |
| 270 | vreg = devm_kzalloc(&spmi->dev, sizeof(*vreg), GFP_KERNEL); |
| 271 | if (!vreg) { |
| 272 | pr_err("allocation failed.\n"); |
| 273 | return -ENOMEM; |
| 274 | } |
| 275 | vreg->spmi_dev = spmi; |
| 276 | |
| 277 | res = spmi_get_resource(spmi, NULL, IORESOURCE_MEM, 0); |
| 278 | if (!res) { |
| 279 | dev_err(&spmi->dev, "%s: node is missing base address\n", |
| 280 | __func__); |
| 281 | return -EINVAL; |
| 282 | } |
| 283 | vreg->spmi_base_addr = res->start; |
| 284 | |
| 285 | rc = qpnp_fts2_check_type(vreg); |
| 286 | if (rc) |
| 287 | return rc; |
| 288 | |
| 289 | /* |
| 290 | * The FTS2 regulator must be initialized to range 0 or range 1 during |
| 291 | * PMIC power on sequence. Once it is set, it cannot be changed |
| 292 | * dynamically. |
| 293 | */ |
| 294 | rc = qpnp_fts2_init_range(vreg); |
| 295 | if (rc) |
| 296 | return rc; |
| 297 | |
| 298 | rc = qpnp_fts2_init_voltage(vreg); |
| 299 | if (rc) |
| 300 | return rc; |
| 301 | |
| 302 | init_data = of_get_regulator_init_data(&spmi->dev, node); |
| 303 | if (!init_data) { |
| 304 | dev_err(&spmi->dev, "%s: unable to allocate memory\n", |
| 305 | __func__); |
| 306 | return -ENOMEM; |
| 307 | } |
| 308 | init_data->constraints.input_uV = init_data->constraints.max_uV; |
| 309 | init_data->constraints.valid_ops_mask |= REGULATOR_CHANGE_STATUS |
| 310 | | REGULATOR_CHANGE_VOLTAGE; |
| 311 | |
| 312 | if (!init_data->constraints.name) { |
| 313 | dev_err(&spmi->dev, "%s: node is missing regulator name\n", |
| 314 | __func__); |
| 315 | return -EINVAL; |
| 316 | } |
| 317 | |
| 318 | vreg->rdesc.name = init_data->constraints.name; |
| 319 | vreg->rdesc.type = REGULATOR_VOLTAGE; |
| 320 | vreg->rdesc.owner = THIS_MODULE; |
| 321 | vreg->rdesc.ops = &spm_regulator_ops; |
| 322 | vreg->rdesc.n_voltages |
| 323 | = (vreg->range->max_uV - vreg->range->set_point_min_uV) |
| 324 | / vreg->range->step_uV + 1; |
| 325 | |
| 326 | vreg->rdev = regulator_register(&vreg->rdesc, &spmi->dev, |
| 327 | init_data, vreg, node); |
| 328 | if (IS_ERR(vreg->rdev)) { |
| 329 | rc = PTR_ERR(vreg->rdev); |
| 330 | dev_err(&spmi->dev, "%s: regulator_register failed, rc=%d\n", |
| 331 | __func__, rc); |
| 332 | return rc; |
| 333 | } |
| 334 | |
| 335 | dev_set_drvdata(&spmi->dev, vreg); |
| 336 | |
| 337 | pr_info("name=%s, range=%d\n", vreg->rdesc.name, |
| 338 | (vreg->range == &fts2_range0) ? 0 : 1); |
| 339 | |
| 340 | return rc; |
| 341 | } |
| 342 | |
| 343 | static int __devexit spm_regulator_remove(struct spmi_device *spmi) |
| 344 | { |
| 345 | struct spm_vreg *vreg = dev_get_drvdata(&spmi->dev); |
| 346 | |
| 347 | regulator_unregister(vreg->rdev); |
| 348 | |
| 349 | return 0; |
| 350 | } |
| 351 | |
| 352 | static struct of_device_id spm_regulator_match_table[] = { |
| 353 | { .compatible = SPM_REGULATOR_DRIVER_NAME, }, |
| 354 | {} |
| 355 | }; |
| 356 | |
| 357 | static const struct spmi_device_id spm_regulator_id[] = { |
| 358 | { SPM_REGULATOR_DRIVER_NAME, 0 }, |
| 359 | {} |
| 360 | }; |
| 361 | MODULE_DEVICE_TABLE(spmi, spm_regulator_id); |
| 362 | |
| 363 | static struct spmi_driver spm_regulator_driver = { |
| 364 | .driver = { |
| 365 | .name = SPM_REGULATOR_DRIVER_NAME, |
| 366 | .of_match_table = spm_regulator_match_table, |
| 367 | .owner = THIS_MODULE, |
| 368 | }, |
| 369 | .probe = spm_regulator_probe, |
| 370 | .remove = __devexit_p(spm_regulator_remove), |
| 371 | .id_table = spm_regulator_id, |
| 372 | }; |
| 373 | |
| 374 | /** |
| 375 | * spm_regulator_init() - register spmi driver for spm-regulator |
| 376 | * |
| 377 | * This initialization function should be called in systems in which driver |
| 378 | * registration ordering must be controlled precisely. |
| 379 | * |
| 380 | * Returns 0 on success or errno on failure. |
| 381 | */ |
| 382 | int __init spm_regulator_init(void) |
| 383 | { |
| 384 | static bool has_registered; |
| 385 | |
| 386 | if (has_registered) |
| 387 | return 0; |
| 388 | else |
| 389 | has_registered = true; |
| 390 | |
| 391 | return spmi_driver_register(&spm_regulator_driver); |
| 392 | } |
| 393 | EXPORT_SYMBOL(spm_regulator_init); |
| 394 | |
| 395 | static void __exit spm_regulator_exit(void) |
| 396 | { |
| 397 | spmi_driver_unregister(&spm_regulator_driver); |
| 398 | } |
| 399 | |
| 400 | arch_initcall(spm_regulator_init); |
| 401 | module_exit(spm_regulator_exit); |
| 402 | |
| 403 | MODULE_LICENSE("GPL v2"); |
| 404 | MODULE_DESCRIPTION("SPM regulator driver"); |
| 405 | MODULE_ALIAS("platform:spm-regulator"); |