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/mfd/core.h> 18 #include <linux/pm_runtime.h> 19 #include <linux/slab.h> 20 #include <linux/module.h> 21 #include <linux/irqdomain.h> 22 #include <linux/of.h> 23 #include <linux/regulator/consumer.h> 24 25 static struct device_type mfd_dev_type = { 26 .name = "mfd_device", 27 }; 28 29 int mfd_cell_enable(struct platform_device *pdev) 30 { 31 const struct mfd_cell *cell = mfd_get_cell(pdev); 32 int err = 0; 33 34 /* only call enable hook if the cell wasn't previously enabled */ 35 if (atomic_inc_return(cell->usage_count) == 1) 36 err = cell->enable(pdev); 37 38 /* if the enable hook failed, decrement counter to allow retries */ 39 if (err) 40 atomic_dec(cell->usage_count); 41 42 return err; 43 } 44 EXPORT_SYMBOL(mfd_cell_enable); 45 46 int mfd_cell_disable(struct platform_device *pdev) 47 { 48 const struct mfd_cell *cell = mfd_get_cell(pdev); 49 int err = 0; 50 51 /* only disable if no other clients are using it */ 52 if (atomic_dec_return(cell->usage_count) == 0) 53 err = cell->disable(pdev); 54 55 /* if the disable hook failed, increment to allow retries */ 56 if (err) 57 atomic_inc(cell->usage_count); 58 59 /* sanity check; did someone call disable too many times? */ 60 WARN_ON(atomic_read(cell->usage_count) < 0); 61 62 return err; 63 } 64 EXPORT_SYMBOL(mfd_cell_disable); 65 66 static int mfd_platform_add_cell(struct platform_device *pdev, 67 const struct mfd_cell *cell, 68 atomic_t *usage_count) 69 { 70 if (!cell) 71 return 0; 72 73 pdev->mfd_cell = kmemdup(cell, sizeof(*cell), GFP_KERNEL); 74 if (!pdev->mfd_cell) 75 return -ENOMEM; 76 77 pdev->mfd_cell->usage_count = usage_count; 78 return 0; 79 } 80 81 static int mfd_add_device(struct device *parent, int id, 82 const struct mfd_cell *cell, atomic_t *usage_count, 83 struct resource *mem_base, 84 int irq_base, struct irq_domain *domain) 85 { 86 struct resource *res; 87 struct platform_device *pdev; 88 struct device_node *np = NULL; 89 int ret = -ENOMEM; 90 int r; 91 92 pdev = platform_device_alloc(cell->name, id + cell->id); 93 if (!pdev) 94 goto fail_alloc; 95 96 res = kzalloc(sizeof(*res) * cell->num_resources, GFP_KERNEL); 97 if (!res) 98 goto fail_device; 99 100 pdev->dev.parent = parent; 101 pdev->dev.type = &mfd_dev_type; 102 pdev->dev.dma_mask = parent->dma_mask; 103 pdev->dev.dma_parms = parent->dma_parms; 104 105 ret = devm_regulator_bulk_register_supply_alias( 106 &pdev->dev, cell->parent_supplies, 107 parent, cell->parent_supplies, 108 cell->num_parent_supplies); 109 if (ret < 0) 110 goto fail_res; 111 112 if (parent->of_node && cell->of_compatible) { 113 for_each_child_of_node(parent->of_node, np) { 114 if (of_device_is_compatible(np, cell->of_compatible)) { 115 pdev->dev.of_node = np; 116 break; 117 } 118 } 119 } 120 121 if (cell->pdata_size) { 122 ret = platform_device_add_data(pdev, 123 cell->platform_data, cell->pdata_size); 124 if (ret) 125 goto fail_alias; 126 } 127 128 ret = mfd_platform_add_cell(pdev, cell, usage_count); 129 if (ret) 130 goto fail_alias; 131 132 for (r = 0; r < cell->num_resources; r++) { 133 res[r].name = cell->resources[r].name; 134 res[r].flags = cell->resources[r].flags; 135 136 /* Find out base to use */ 137 if ((cell->resources[r].flags & IORESOURCE_MEM) && mem_base) { 138 res[r].parent = mem_base; 139 res[r].start = mem_base->start + 140 cell->resources[r].start; 141 res[r].end = mem_base->start + 142 cell->resources[r].end; 143 } else if (cell->resources[r].flags & IORESOURCE_IRQ) { 144 if (domain) { 145 /* Unable to create mappings for IRQ ranges. */ 146 WARN_ON(cell->resources[r].start != 147 cell->resources[r].end); 148 res[r].start = res[r].end = irq_create_mapping( 149 domain, cell->resources[r].start); 150 } else { 151 res[r].start = irq_base + 152 cell->resources[r].start; 153 res[r].end = irq_base + 154 cell->resources[r].end; 155 } 156 } else { 157 res[r].parent = cell->resources[r].parent; 158 res[r].start = cell->resources[r].start; 159 res[r].end = cell->resources[r].end; 160 } 161 162 if (!cell->ignore_resource_conflicts) { 163 ret = acpi_check_resource_conflict(&res[r]); 164 if (ret) 165 goto fail_alias; 166 } 167 } 168 169 ret = platform_device_add_resources(pdev, res, cell->num_resources); 170 if (ret) 171 goto fail_alias; 172 173 ret = platform_device_add(pdev); 174 if (ret) 175 goto fail_alias; 176 177 if (cell->pm_runtime_no_callbacks) 178 pm_runtime_no_callbacks(&pdev->dev); 179 180 kfree(res); 181 182 return 0; 183 184 fail_alias: 185 devm_regulator_bulk_unregister_supply_alias(&pdev->dev, 186 cell->parent_supplies, 187 cell->num_parent_supplies); 188 fail_res: 189 kfree(res); 190 fail_device: 191 platform_device_put(pdev); 192 fail_alloc: 193 return ret; 194 } 195 196 int mfd_add_devices(struct device *parent, int id, 197 const struct mfd_cell *cells, int n_devs, 198 struct resource *mem_base, 199 int irq_base, struct irq_domain *domain) 200 { 201 int i; 202 int ret; 203 atomic_t *cnts; 204 205 /* initialize reference counting for all cells */ 206 cnts = kcalloc(n_devs, sizeof(*cnts), GFP_KERNEL); 207 if (!cnts) 208 return -ENOMEM; 209 210 for (i = 0; i < n_devs; i++) { 211 atomic_set(&cnts[i], 0); 212 ret = mfd_add_device(parent, id, cells + i, cnts + i, mem_base, 213 irq_base, domain); 214 if (ret) 215 goto fail; 216 } 217 218 return 0; 219 220 fail: 221 if (i) 222 mfd_remove_devices(parent); 223 else 224 kfree(cnts); 225 return ret; 226 } 227 EXPORT_SYMBOL(mfd_add_devices); 228 229 static int mfd_remove_devices_fn(struct device *dev, void *c) 230 { 231 struct platform_device *pdev; 232 const struct mfd_cell *cell; 233 atomic_t **usage_count = c; 234 235 if (dev->type != &mfd_dev_type) 236 return 0; 237 238 pdev = to_platform_device(dev); 239 cell = mfd_get_cell(pdev); 240 241 /* find the base address of usage_count pointers (for freeing) */ 242 if (!*usage_count || (cell->usage_count < *usage_count)) 243 *usage_count = cell->usage_count; 244 245 platform_device_unregister(pdev); 246 return 0; 247 } 248 249 void mfd_remove_devices(struct device *parent) 250 { 251 atomic_t *cnts = NULL; 252 253 device_for_each_child(parent, &cnts, mfd_remove_devices_fn); 254 kfree(cnts); 255 } 256 EXPORT_SYMBOL(mfd_remove_devices); 257 258 int mfd_clone_cell(const char *cell, const char **clones, size_t n_clones) 259 { 260 struct mfd_cell cell_entry; 261 struct device *dev; 262 struct platform_device *pdev; 263 int i; 264 265 /* fetch the parent cell's device (should already be registered!) */ 266 dev = bus_find_device_by_name(&platform_bus_type, NULL, cell); 267 if (!dev) { 268 printk(KERN_ERR "failed to find device for cell %s\n", cell); 269 return -ENODEV; 270 } 271 pdev = to_platform_device(dev); 272 memcpy(&cell_entry, mfd_get_cell(pdev), sizeof(cell_entry)); 273 274 WARN_ON(!cell_entry.enable); 275 276 for (i = 0; i < n_clones; i++) { 277 cell_entry.name = clones[i]; 278 /* don't give up if a single call fails; just report error */ 279 if (mfd_add_device(pdev->dev.parent, -1, &cell_entry, 280 cell_entry.usage_count, NULL, 0, NULL)) 281 dev_err(dev, "failed to create platform device '%s'\n", 282 clones[i]); 283 } 284 285 return 0; 286 } 287 EXPORT_SYMBOL(mfd_clone_cell); 288 289 MODULE_LICENSE("GPL"); 290 MODULE_AUTHOR("Ian Molton, Dmitry Baryshkov"); 291