1 /* 2 * drivers/mfd/mfd-core.c 3 * 4 * core MFD support 5 * Copyright (c) 2006 Ian Molton 6 * Copyright (c) 2007,2008 Dmitry Baryshkov 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 * 12 */ 13 14 #include <linux/kernel.h> 15 #include <linux/platform_device.h> 16 #include <linux/acpi.h> 17 #include <linux/property.h> 18 #include <linux/mfd/core.h> 19 #include <linux/pm_runtime.h> 20 #include <linux/slab.h> 21 #include <linux/module.h> 22 #include <linux/irqdomain.h> 23 #include <linux/of.h> 24 #include <linux/regulator/consumer.h> 25 26 static struct device_type mfd_dev_type = { 27 .name = "mfd_device", 28 }; 29 30 int mfd_cell_enable(struct platform_device *pdev) 31 { 32 const struct mfd_cell *cell = mfd_get_cell(pdev); 33 int err = 0; 34 35 /* only call enable hook if the cell wasn't previously enabled */ 36 if (atomic_inc_return(cell->usage_count) == 1) 37 err = cell->enable(pdev); 38 39 /* if the enable hook failed, decrement counter to allow retries */ 40 if (err) 41 atomic_dec(cell->usage_count); 42 43 return err; 44 } 45 EXPORT_SYMBOL(mfd_cell_enable); 46 47 int mfd_cell_disable(struct platform_device *pdev) 48 { 49 const struct mfd_cell *cell = mfd_get_cell(pdev); 50 int err = 0; 51 52 /* only disable if no other clients are using it */ 53 if (atomic_dec_return(cell->usage_count) == 0) 54 err = cell->disable(pdev); 55 56 /* if the disable hook failed, increment to allow retries */ 57 if (err) 58 atomic_inc(cell->usage_count); 59 60 /* sanity check; did someone call disable too many times? */ 61 WARN_ON(atomic_read(cell->usage_count) < 0); 62 63 return err; 64 } 65 EXPORT_SYMBOL(mfd_cell_disable); 66 67 static int mfd_platform_add_cell(struct platform_device *pdev, 68 const struct mfd_cell *cell, 69 atomic_t *usage_count) 70 { 71 if (!cell) 72 return 0; 73 74 pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL); 75 if (!pdev->mfd_cell) 76 return -ENOMEM; 77 78 pdev->mfd_cell->usage_count = usage_count; 79 return 0; 80 } 81 82 #if IS_ENABLED(CONFIG_ACPI) 83 static void mfd_acpi_add_device(const struct mfd_cell *cell, 84 struct platform_device *pdev) 85 { 86 const struct mfd_cell_acpi_match *match = cell->acpi_match; 87 struct acpi_device *parent, *child; 88 struct acpi_device *adev; 89 90 parent = ACPI_COMPANION(pdev->dev.parent); 91 if (!parent) 92 return; 93 94 /* 95 * MFD child device gets its ACPI handle either from the ACPI device 96 * directly under the parent that matches the either _HID or _CID, or 97 * _ADR or it will use the parent handle if is no ID is given. 98 * 99 * Note that use of _ADR is a grey area in the ACPI specification, 100 * though Intel Galileo Gen2 is using it to distinguish the children 101 * devices. 102 */ 103 adev = parent; 104 if (match) { 105 if (match->pnpid) { 106 struct acpi_device_id ids[2] = {}; 107 108 strlcpy(ids[0].id, match->pnpid, sizeof(ids[0].id)); 109 list_for_each_entry(child, &parent->children, node) { 110 if (!acpi_match_device_ids(child, ids)) { 111 adev = child; 112 break; 113 } 114 } 115 } else { 116 unsigned long long adr; 117 acpi_status status; 118 119 list_for_each_entry(child, &parent->children, node) { 120 status = acpi_evaluate_integer(child->handle, 121 "_ADR", NULL, 122 &adr); 123 if (ACPI_SUCCESS(status) && match->adr == adr) { 124 adev = child; 125 break; 126 } 127 } 128 } 129 } 130 131 ACPI_COMPANION_SET(&pdev->dev, adev); 132 } 133 #else 134 static inline void mfd_acpi_add_device(const struct mfd_cell *cell, 135 struct platform_device *pdev) 136 { 137 } 138 #endif 139 140 static int mfd_add_device(struct device *parent, int id, 141 const struct mfd_cell *cell, atomic_t *usage_count, 142 struct resource *mem_base, 143 int irq_base, struct irq_domain *domain) 144 { 145 struct resource *res; 146 struct platform_device *pdev; 147 struct device_node *np = NULL; 148 int ret = -ENOMEM; 149 int platform_id; 150 int r; 151 152 if (id == PLATFORM_DEVID_AUTO) 153 platform_id = id; 154 else 155 platform_id = id + cell->id; 156 157 pdev = platform_device_alloc(cell->name, platform_id); 158 if (!pdev) 159 goto fail_alloc; 160 161 res = kzalloc(sizeof(*res) * cell->num_resources, GFP_KERNEL); 162 if (!res) 163 goto fail_device; 164 165 pdev->dev.parent = parent; 166 pdev->dev.type = &mfd_dev_type; 167 pdev->dev.dma_mask = parent->dma_mask; 168 pdev->dev.dma_parms = parent->dma_parms; 169 pdev->dev.coherent_dma_mask = parent->coherent_dma_mask; 170 171 ret = regulator_bulk_register_supply_alias( 172 &pdev->dev, cell->parent_supplies, 173 parent, cell->parent_supplies, 174 cell->num_parent_supplies); 175 if (ret < 0) 176 goto fail_res; 177 178 if (parent->of_node && cell->of_compatible) { 179 for_each_child_of_node(parent->of_node, np) { 180 if (of_device_is_compatible(np, cell->of_compatible)) { 181 pdev->dev.of_node = np; 182 break; 183 } 184 } 185 } 186 187 mfd_acpi_add_device(cell, pdev); 188 189 if (cell->pdata_size) { 190 ret = platform_device_add_data(pdev, 191 cell->platform_data, cell->pdata_size); 192 if (ret) 193 goto fail_alias; 194 } 195 196 if (cell->properties) { 197 ret = platform_device_add_properties(pdev, cell->properties); 198 if (ret) 199 goto fail_alias; 200 } 201 202 ret = mfd_platform_add_cell(pdev, cell, usage_count); 203 if (ret) 204 goto fail_alias; 205 206 for (r = 0; r < cell->num_resources; r++) { 207 res[r].name = cell->resources[r].name; 208 res[r].flags = cell->resources[r].flags; 209 210 /* Find out base to use */ 211 if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) { 212 res[r].parent = mem_base; 213 res[r].start = mem_base->start + 214 cell->resources[r].start; 215 res[r].end = mem_base->start + 216 cell->resources[r].end; 217 } else if (cell->resources[r].flags & IORESOURCE_IRQ) { 218 if (domain) { 219 /* Unable to create mappings for IRQ ranges. */ 220 WARN_ON(cell->resources[r].start != 221 cell->resources[r].end); 222 res[r].start = res[r].end = irq_create_mapping( 223 domain, cell->resources[r].start); 224 } else { 225 res[r].start = irq_base + 226 cell->resources[r].start; 227 res[r].end = irq_base + 228 cell->resources[r].end; 229 } 230 } else { 231 res[r].parent = cell->resources[r].parent; 232 res[r].start = cell->resources[r].start; 233 res[r].end = cell->resources[r].end; 234 } 235 236 if (!cell->ignore_resource_conflicts) { 237 if (has_acpi_companion(&pdev->dev)) { 238 ret = acpi_check_resource_conflict(&res[r]); 239 if (ret) 240 goto fail_alias; 241 } 242 } 243 } 244 245 ret = platform_device_add_resources(pdev, res, cell->num_resources); 246 if (ret) 247 goto fail_alias; 248 249 ret = platform_device_add(pdev); 250 if (ret) 251 goto fail_alias; 252 253 if (cell->pm_runtime_no_callbacks) 254 pm_runtime_no_callbacks(&pdev->dev); 255 256 kfree(res); 257 258 return 0; 259 260 fail_alias: 261 regulator_bulk_unregister_supply_alias(&pdev->dev, 262 cell->parent_supplies, 263 cell->num_parent_supplies); 264 fail_res: 265 kfree(res); 266 fail_device: 267 platform_device_put(pdev); 268 fail_alloc: 269 return ret; 270 } 271 272 int mfd_add_devices(struct device *parent, int id, 273 const struct mfd_cell *cells, int n_devs, 274 struct resource *mem_base, 275 int irq_base, struct irq_domain *domain) 276 { 277 int i; 278 int ret; 279 atomic_t *cnts; 280 281 /* initialize reference counting for all cells */ 282 cnts = kcalloc(n_devs, sizeof(*cnts), GFP_KERNEL); 283 if (!cnts) 284 return -ENOMEM; 285 286 for (i = 0; i < n_devs; i++) { 287 atomic_set(&cnts[i], 0); 288 ret = mfd_add_device(parent, id, cells + i, cnts + i, mem_base, 289 irq_base, domain); 290 if (ret) 291 goto fail; 292 } 293 294 return 0; 295 296 fail: 297 if (i) 298 mfd_remove_devices(parent); 299 else 300 kfree(cnts); 301 return ret; 302 } 303 EXPORT_SYMBOL(mfd_add_devices); 304 305 static int mfd_remove_devices_fn(struct device *dev, void *c) 306 { 307 struct platform_device *pdev; 308 const struct mfd_cell *cell; 309 atomic_t **usage_count = c; 310 311 if (dev->type != &mfd_dev_type) 312 return 0; 313 314 pdev = to_platform_device(dev); 315 cell = mfd_get_cell(pdev); 316 317 regulator_bulk_unregister_supply_alias(dev, cell->parent_supplies, 318 cell->num_parent_supplies); 319 320 /* find the base address of usage_count pointers (for freeing) */ 321 if (!*usage_count || (cell->usage_count < *usage_count)) 322 *usage_count = cell->usage_count; 323 324 platform_device_unregister(pdev); 325 return 0; 326 } 327 328 void mfd_remove_devices(struct device *parent) 329 { 330 atomic_t *cnts = NULL; 331 332 device_for_each_child_reverse(parent, &cnts, mfd_remove_devices_fn); 333 kfree(cnts); 334 } 335 EXPORT_SYMBOL(mfd_remove_devices); 336 337 static void devm_mfd_dev_release(struct device *dev, void *res) 338 { 339 mfd_remove_devices(dev); 340 } 341 342 /** 343 * devm_mfd_add_devices - Resource managed version of mfd_add_devices() 344 * 345 * Returns 0 on success or an appropriate negative error number on failure. 346 * All child-devices of the MFD will automatically be removed when it gets 347 * unbinded. 348 */ 349 int devm_mfd_add_devices(struct device *dev, int id, 350 const struct mfd_cell *cells, int n_devs, 351 struct resource *mem_base, 352 int irq_base, struct irq_domain *domain) 353 { 354 struct device **ptr; 355 int ret; 356 357 ptr = devres_alloc(devm_mfd_dev_release, sizeof(*ptr), GFP_KERNEL); 358 if (!ptr) 359 return -ENOMEM; 360 361 ret = mfd_add_devices(dev, id, cells, n_devs, mem_base, 362 irq_base, domain); 363 if (ret < 0) { 364 devres_free(ptr); 365 return ret; 366 } 367 368 *ptr = dev; 369 devres_add(dev, ptr); 370 371 return ret; 372 } 373 EXPORT_SYMBOL(devm_mfd_add_devices); 374 375 int mfd_clone_cell(const char *cell, const char **clones, size_t n_clones) 376 { 377 struct mfd_cell cell_entry; 378 struct device *dev; 379 struct platform_device *pdev; 380 int i; 381 382 /* fetch the parent cell's device (should already be registered!) */ 383 dev = bus_find_device_by_name(&platform_bus_type, NULL, cell); 384 if (!dev) { 385 printk(KERN_ERR "failed to find device for cell %s\n", cell); 386 return -ENODEV; 387 } 388 pdev = to_platform_device(dev); 389 memcpy(&cell_entry, mfd_get_cell(pdev), sizeof(cell_entry)); 390 391 WARN_ON(!cell_entry.enable); 392 393 for (i = 0; i < n_clones; i++) { 394 cell_entry.name = clones[i]; 395 /* don't give up if a single call fails; just report error */ 396 if (mfd_add_device(pdev->dev.parent, -1, &cell_entry, 397 cell_entry.usage_count, NULL, 0, NULL)) 398 dev_err(dev, "failed to create platform device '%s'\n", 399 clones[i]); 400 } 401 402 return 0; 403 } 404 EXPORT_SYMBOL(mfd_clone_cell); 405 406 MODULE_LICENSE("GPL"); 407 MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov"); 408