1 // SPDX--License-Identifier: GPL-2.0 2 3 #include <asm/platform_early.h> 4 #include <linux/mod_devicetable.h> 5 #include <linux/pm.h> 6 7 static __initdata LIST_HEAD(sh_early_platform_driver_list); 8 static __initdata LIST_HEAD(sh_early_platform_device_list); 9 10 static const struct platform_device_id * 11 platform_match_id(const struct platform_device_id *id, 12 struct platform_device *pdev) 13 { 14 while (id->name[0]) { 15 if (strcmp(pdev->name, id->name) == 0) { 16 pdev->id_entry = id; 17 return id; 18 } 19 id++; 20 } 21 return NULL; 22 } 23 24 static int platform_match(struct device *dev, struct device_driver *drv) 25 { 26 struct platform_device *pdev = to_platform_device(dev); 27 struct platform_driver *pdrv = to_platform_driver(drv); 28 29 /* When driver_override is set, only bind to the matching driver */ 30 if (pdev->driver_override) 31 return !strcmp(pdev->driver_override, drv->name); 32 33 /* Then try to match against the id table */ 34 if (pdrv->id_table) 35 return platform_match_id(pdrv->id_table, pdev) != NULL; 36 37 /* fall-back to driver name match */ 38 return (strcmp(pdev->name, drv->name) == 0); 39 } 40 41 #ifdef CONFIG_PM 42 static void device_pm_init_common(struct device *dev) 43 { 44 if (!dev->power.early_init) { 45 spin_lock_init(&dev->power.lock); 46 dev->power.qos = NULL; 47 dev->power.early_init = true; 48 } 49 } 50 51 static void pm_runtime_early_init(struct device *dev) 52 { 53 dev->power.disable_depth = 1; 54 device_pm_init_common(dev); 55 } 56 #else 57 static void pm_runtime_early_init(struct device *dev) {} 58 #endif 59 60 /** 61 * sh_early_platform_driver_register - register early platform driver 62 * @epdrv: sh_early_platform driver structure 63 * @buf: string passed from early_param() 64 * 65 * Helper function for sh_early_platform_init() / sh_early_platform_init_buffer() 66 */ 67 int __init sh_early_platform_driver_register(struct sh_early_platform_driver *epdrv, 68 char *buf) 69 { 70 char *tmp; 71 int n; 72 73 /* Simply add the driver to the end of the global list. 74 * Drivers will by default be put on the list in compiled-in order. 75 */ 76 if (!epdrv->list.next) { 77 INIT_LIST_HEAD(&epdrv->list); 78 list_add_tail(&epdrv->list, &sh_early_platform_driver_list); 79 } 80 81 /* If the user has specified device then make sure the driver 82 * gets prioritized. The driver of the last device specified on 83 * command line will be put first on the list. 84 */ 85 n = strlen(epdrv->pdrv->driver.name); 86 if (buf && !strncmp(buf, epdrv->pdrv->driver.name, n)) { 87 list_move(&epdrv->list, &sh_early_platform_driver_list); 88 89 /* Allow passing parameters after device name */ 90 if (buf[n] == '\0' || buf[n] == ',') 91 epdrv->requested_id = -1; 92 else { 93 epdrv->requested_id = simple_strtoul(&buf[n + 1], 94 &tmp, 10); 95 96 if (buf[n] != '.' || (tmp == &buf[n + 1])) { 97 epdrv->requested_id = EARLY_PLATFORM_ID_ERROR; 98 n = 0; 99 } else 100 n += strcspn(&buf[n + 1], ",") + 1; 101 } 102 103 if (buf[n] == ',') 104 n++; 105 106 if (epdrv->bufsize) { 107 memcpy(epdrv->buffer, &buf[n], 108 min_t(int, epdrv->bufsize, strlen(&buf[n]) + 1)); 109 epdrv->buffer[epdrv->bufsize - 1] = '\0'; 110 } 111 } 112 113 return 0; 114 } 115 116 /** 117 * sh_early_platform_add_devices - adds a number of early platform devices 118 * @devs: array of early platform devices to add 119 * @num: number of early platform devices in array 120 * 121 * Used by early architecture code to register early platform devices and 122 * their platform data. 123 */ 124 void __init sh_early_platform_add_devices(struct platform_device **devs, int num) 125 { 126 struct device *dev; 127 int i; 128 129 /* simply add the devices to list */ 130 for (i = 0; i < num; i++) { 131 dev = &devs[i]->dev; 132 133 if (!dev->devres_head.next) { 134 pm_runtime_early_init(dev); 135 INIT_LIST_HEAD(&dev->devres_head); 136 list_add_tail(&dev->devres_head, 137 &sh_early_platform_device_list); 138 } 139 } 140 } 141 142 /** 143 * sh_early_platform_driver_register_all - register early platform drivers 144 * @class_str: string to identify early platform driver class 145 * 146 * Used by architecture code to register all early platform drivers 147 * for a certain class. If omitted then only early platform drivers 148 * with matching kernel command line class parameters will be registered. 149 */ 150 void __init sh_early_platform_driver_register_all(char *class_str) 151 { 152 /* The "class_str" parameter may or may not be present on the kernel 153 * command line. If it is present then there may be more than one 154 * matching parameter. 155 * 156 * Since we register our early platform drivers using early_param() 157 * we need to make sure that they also get registered in the case 158 * when the parameter is missing from the kernel command line. 159 * 160 * We use parse_early_options() to make sure the early_param() gets 161 * called at least once. The early_param() may be called more than 162 * once since the name of the preferred device may be specified on 163 * the kernel command line. sh_early_platform_driver_register() handles 164 * this case for us. 165 */ 166 parse_early_options(class_str); 167 } 168 169 /** 170 * sh_early_platform_match - find early platform device matching driver 171 * @epdrv: early platform driver structure 172 * @id: id to match against 173 */ 174 static struct platform_device * __init 175 sh_early_platform_match(struct sh_early_platform_driver *epdrv, int id) 176 { 177 struct platform_device *pd; 178 179 list_for_each_entry(pd, &sh_early_platform_device_list, dev.devres_head) 180 if (platform_match(&pd->dev, &epdrv->pdrv->driver)) 181 if (pd->id == id) 182 return pd; 183 184 return NULL; 185 } 186 187 /** 188 * sh_early_platform_left - check if early platform driver has matching devices 189 * @epdrv: early platform driver structure 190 * @id: return true if id or above exists 191 */ 192 static int __init sh_early_platform_left(struct sh_early_platform_driver *epdrv, 193 int id) 194 { 195 struct platform_device *pd; 196 197 list_for_each_entry(pd, &sh_early_platform_device_list, dev.devres_head) 198 if (platform_match(&pd->dev, &epdrv->pdrv->driver)) 199 if (pd->id >= id) 200 return 1; 201 202 return 0; 203 } 204 205 /** 206 * sh_early_platform_driver_probe_id - probe drivers matching class_str and id 207 * @class_str: string to identify early platform driver class 208 * @id: id to match against 209 * @nr_probe: number of platform devices to successfully probe before exiting 210 */ 211 static int __init sh_early_platform_driver_probe_id(char *class_str, 212 int id, 213 int nr_probe) 214 { 215 struct sh_early_platform_driver *epdrv; 216 struct platform_device *match; 217 int match_id; 218 int n = 0; 219 int left = 0; 220 221 list_for_each_entry(epdrv, &sh_early_platform_driver_list, list) { 222 /* only use drivers matching our class_str */ 223 if (strcmp(class_str, epdrv->class_str)) 224 continue; 225 226 if (id == -2) { 227 match_id = epdrv->requested_id; 228 left = 1; 229 230 } else { 231 match_id = id; 232 left += sh_early_platform_left(epdrv, id); 233 234 /* skip requested id */ 235 switch (epdrv->requested_id) { 236 case EARLY_PLATFORM_ID_ERROR: 237 case EARLY_PLATFORM_ID_UNSET: 238 break; 239 default: 240 if (epdrv->requested_id == id) 241 match_id = EARLY_PLATFORM_ID_UNSET; 242 } 243 } 244 245 switch (match_id) { 246 case EARLY_PLATFORM_ID_ERROR: 247 pr_warn("%s: unable to parse %s parameter\n", 248 class_str, epdrv->pdrv->driver.name); 249 fallthrough; 250 case EARLY_PLATFORM_ID_UNSET: 251 match = NULL; 252 break; 253 default: 254 match = sh_early_platform_match(epdrv, match_id); 255 } 256 257 if (match) { 258 /* 259 * Set up a sensible init_name to enable 260 * dev_name() and others to be used before the 261 * rest of the driver core is initialized. 262 */ 263 if (!match->dev.init_name && slab_is_available()) { 264 if (match->id != -1) 265 match->dev.init_name = 266 kasprintf(GFP_KERNEL, "%s.%d", 267 match->name, 268 match->id); 269 else 270 match->dev.init_name = 271 kasprintf(GFP_KERNEL, "%s", 272 match->name); 273 274 if (!match->dev.init_name) 275 return -ENOMEM; 276 } 277 278 if (epdrv->pdrv->probe(match)) 279 pr_warn("%s: unable to probe %s early.\n", 280 class_str, match->name); 281 else 282 n++; 283 } 284 285 if (n >= nr_probe) 286 break; 287 } 288 289 if (left) 290 return n; 291 else 292 return -ENODEV; 293 } 294 295 /** 296 * sh_early_platform_driver_probe - probe a class of registered drivers 297 * @class_str: string to identify early platform driver class 298 * @nr_probe: number of platform devices to successfully probe before exiting 299 * @user_only: only probe user specified early platform devices 300 * 301 * Used by architecture code to probe registered early platform drivers 302 * within a certain class. For probe to happen a registered early platform 303 * device matching a registered early platform driver is needed. 304 */ 305 int __init sh_early_platform_driver_probe(char *class_str, 306 int nr_probe, 307 int user_only) 308 { 309 int k, n, i; 310 311 n = 0; 312 for (i = -2; n < nr_probe; i++) { 313 k = sh_early_platform_driver_probe_id(class_str, i, nr_probe - n); 314 315 if (k < 0) 316 break; 317 318 n += k; 319 320 if (user_only) 321 break; 322 } 323 324 return n; 325 } 326 327 /** 328 * early_platform_cleanup - clean up early platform code 329 */ 330 void __init early_platform_cleanup(void) 331 { 332 struct platform_device *pd, *pd2; 333 334 /* clean up the devres list used to chain devices */ 335 list_for_each_entry_safe(pd, pd2, &sh_early_platform_device_list, 336 dev.devres_head) { 337 list_del(&pd->dev.devres_head); 338 memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head)); 339 } 340 } 341