drivers/pinctrl/pinctrl-uclass.c

   1 /*
   2  * Copyright (C) 2015  Masahiro Yamada <yamada.masahiro@socionext.com>
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include <common.h>
   8 #include <libfdt.h>
   9 #include <linux/err.h>
  10 #include <linux/list.h>
  11 #include <dm/device.h>
  12 #include <dm/lists.h>
  13 #include <dm/pinctrl.h>
  14 #include <dm/uclass.h>
  15
  16 DECLARE_GLOBAL_DATA_PTR;
  17
  18 #if CONFIG_IS_ENABLED(PINCTRL_FULL)
  19 /**
  20  * pinctrl_config_one() - apply pinctrl settings for a single node
  21  *
  22  * @config: pin configuration node
  23  * @return: 0 on success, or negative error code on failure
  24  */
  25 static int pinctrl_config_one(struct udevice *config)
  26 {
  27         struct udevice *pctldev;
  28         const struct pinctrl_ops *ops;
  29
  30         pctldev = config;
  31         for (;;) {
  32                 pctldev = dev_get_parent(pctldev);
  33                 if (!pctldev) {
  34                         dev_err(config, "could not find pctldev\n");
  35                         return -EINVAL;
  36                 }
  37                 if (pctldev->uclass->uc_drv->id == UCLASS_PINCTRL)
  38                         break;
  39         }
  40
  41         ops = pinctrl_get_ops(pctldev);
  42         return ops->set_state(pctldev, config);
  43 }
  44
  45 /**
  46  * pinctrl_select_state_full() - full implementation of pinctrl_select_state
  47  *
  48  * @dev: peripheral device
  49  * @statename: state name, like "default"
  50  * @return: 0 on success, or negative error code on failure
  51  */
  52 static int pinctrl_select_state_full(struct udevice *dev, const char *statename)
  53 {
  54         const void *fdt = gd->fdt_blob;
  55         int node = dev->of_offset;
  56         char propname[32]; /* long enough */
  57         const fdt32_t *list;
  58         uint32_t phandle;
  59         int config_node;
  60         struct udevice *config;
  61         int state, size, i, ret;
  62
  63         state = fdt_find_string(fdt, node, "pinctrl-names", statename);
  64         if (state < 0) {
  65                 char *end;
  66                 /*
  67                  * If statename is not found in "pinctrl-names",
  68                  * assume statename is just the integer state ID.
  69                  */
  70                 state = simple_strtoul(statename, &end, 10);
  71                 if (*end)
  72                         return -EINVAL;
  73         }
  74
  75         snprintf(propname, sizeof(propname), "pinctrl-%d", state);
  76         list = fdt_getprop(fdt, node, propname, &size);
  77         if (!list)
  78                 return -EINVAL;
  79
  80         size /= sizeof(*list);
  81         for (i = 0; i < size; i++) {
  82                 phandle = fdt32_to_cpu(*list++);
  83
  84                 config_node = fdt_node_offset_by_phandle(fdt, phandle);
  85                 if (config_node < 0) {
  86                         dev_err(dev, "prop %s index %d invalid phandle\n",
  87                                 propname, i);
  88                         return -EINVAL;
  89                 }
  90                 ret = uclass_get_device_by_of_offset(UCLASS_PINCONFIG,
  91                                                      config_node, &config);
  92                 if (ret)
  93                         return ret;
  94
  95                 ret = pinctrl_config_one(config);
  96                 if (ret)
  97                         return ret;
  98         }
  99
 100         return 0;
 101 }
 102
 103 /**
 104  * pinconfig_post-bind() - post binding for PINCONFIG uclass
 105  * Recursively bind its children as pinconfig devices.
 106  *
 107  * @dev: pinconfig device
 108  * @return: 0 on success, or negative error code on failure
 109  */
 110 static int pinconfig_post_bind(struct udevice *dev)
 111 {
 112         const void *fdt = gd->fdt_blob;
 113         int offset = dev->of_offset;
 114         const char *name;
 115         int ret;
 116
 117         for (offset = fdt_first_subnode(fdt, offset);
 118              offset > 0;
 119              offset = fdt_next_subnode(fdt, offset)) {
 120                 /*
 121                  * If this node has "compatible" property, this is not
 122                  * a pin configuration node, but a normal device. skip.
 123                  */
 124                 fdt_get_property(fdt, offset, "compatible", &ret);
 125                 if (ret >= 0)
 126                         continue;
 127
 128                 if (ret != -FDT_ERR_NOTFOUND)
 129                         return ret;
 130
 131                 name = fdt_get_name(fdt, offset, NULL);
 132                 if (!name)
 133                         return -EINVAL;
 134                 ret = device_bind_driver_to_node(dev, "pinconfig", name,
 135                                                  offset, NULL);
 136                 if (ret)
 137                         return ret;
 138         }
 139
 140         return 0;
 141 }
 142
 143 UCLASS_DRIVER(pinconfig) = {
 144         .id = UCLASS_PINCONFIG,
 145         .post_bind = pinconfig_post_bind,
 146         .name = "pinconfig",
 147 };
 148
 149 U_BOOT_DRIVER(pinconfig_generic) = {
 150         .name = "pinconfig",
 151         .id = UCLASS_PINCONFIG,
 152 };
 153
 154 #else
 155 static int pinctrl_select_state_full(struct udevice *dev, const char *statename)
 156 {
 157         return -ENODEV;
 158 }
 159
 160 static int pinconfig_post_bind(struct udevice *dev)
 161 {
 162         return 0;
 163 }
 164 #endif
 165
 166 /**
 167  * pinctrl_select_state_simple() - simple implementation of pinctrl_select_state
 168  *
 169  * @dev: peripheral device
 170  * @return: 0 on success, or negative error code on failure
 171  */
 172 static int pinctrl_select_state_simple(struct udevice *dev)
 173 {
 174         struct udevice *pctldev;
 175         struct pinctrl_ops *ops;
 176         int ret;
 177
 178         /*
 179          * For simplicity, assume the first device of PINCTRL uclass
 180          * is the correct one.  This is most likely OK as there is
 181          * usually only one pinctrl device on the system.
 182          */
 183         ret = uclass_get_device(UCLASS_PINCTRL, 0, &pctldev);
 184         if (ret)
 185                 return ret;
 186
 187         ops = pinctrl_get_ops(pctldev);
 188         if (!ops->set_state_simple) {
 189                 dev_dbg(dev, "set_state_simple op missing\n");
 190                 return -ENOSYS;
 191         }
 192
 193         return ops->set_state_simple(pctldev, dev);
 194 }
 195
 196 int pinctrl_select_state(struct udevice *dev, const char *statename)
 197 {
 198         /*
 199          * Try full-implemented pinctrl first.
 200          * If it fails or is not implemented, try simple one.
 201          */
 202         if (pinctrl_select_state_full(dev, statename))
 203                 return pinctrl_select_state_simple(dev);
 204
 205         return 0;
 206 }
 207
 208 int pinctrl_request(struct udevice *dev, int func, int flags)
 209 {
 210         struct pinctrl_ops *ops = pinctrl_get_ops(dev);
 211
 212         if (!ops->request)
 213                 return -ENOSYS;
 214
 215         return ops->request(dev, func, flags);
 216 }
 217
 218 int pinctrl_request_noflags(struct udevice *dev, int func)
 219 {
 220         return pinctrl_request(dev, func, 0);
 221 }
 222
 223 int pinctrl_get_periph_id(struct udevice *dev, struct udevice *periph)
 224 {
 225         struct pinctrl_ops *ops = pinctrl_get_ops(dev);
 226
 227         if (!ops->get_periph_id)
 228                 return -ENOSYS;
 229
 230         return ops->get_periph_id(dev, periph);
 231 }
 232
 233 /**
 234  * pinconfig_post-bind() - post binding for PINCTRL uclass
 235  * Recursively bind child nodes as pinconfig devices in case of full pinctrl.
 236  *
 237  * @dev: pinctrl device
 238  * @return: 0 on success, or negative error code on failure
 239  */
 240 static int pinctrl_post_bind(struct udevice *dev)
 241 {
 242         const struct pinctrl_ops *ops = pinctrl_get_ops(dev);
 243
 244         if (!ops) {
 245                 dev_dbg(dev, "ops is not set.  Do not bind.\n");
 246                 return -EINVAL;
 247         }
 248
 249         /*
 250          * If set_state callback is set, we assume this pinctrl driver is the
 251          * full implementation.  In this case, its child nodes should be bound
 252          * so that peripheral devices can easily search in parent devices
 253          * during later DT-parsing.
 254          */
 255         if (ops->set_state)
 256                 return pinconfig_post_bind(dev);
 257
 258         return 0;
 259 }
 260
 261 UCLASS_DRIVER(pinctrl) = {
 262         .id = UCLASS_PINCTRL,
 263         .post_bind = pinctrl_post_bind,
 264         .name = "pinctrl",
 265 };