kernel/drivers/pinctrl/spear/pinctrl-spear.c

   1 /*
   2  * Driver for the ST Microelectronics SPEAr pinmux
   3  *
   4  * Copyright (C) 2012 ST Microelectronics
   5  * Viresh Kumar <viresh.linux@gmail.com>
   6  *
   7  * Inspired from:
   8  * - U300 Pinctl drivers
   9  * - Tegra Pinctl drivers
  10  *
  11  * This file is licensed under the terms of the GNU General Public
  12  * License version 2. This program is licensed "as is" without any
  13  * warranty of any kind, whether express or implied.
  14  */
  15
  16 #include <linux/err.h>
  17 #include <linux/module.h>
  18 #include <linux/of.h>
  19 #include <linux/of_address.h>
  20 #include <linux/of_gpio.h>
  21 #include <linux/pinctrl/machine.h>
  22 #include <linux/pinctrl/pinctrl.h>
  23 #include <linux/pinctrl/pinmux.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/slab.h>
  26
  27 #include "pinctrl-spear.h"
  28
  29 #define DRIVER_NAME "spear-pinmux"
  30
  31 static void muxregs_endisable(struct spear_pmx *pmx,
  32                 struct spear_muxreg *muxregs, u8 count, bool enable)
  33 {
  34         struct spear_muxreg *muxreg;
  35         u32 val, temp, j;
  36
  37         for (j = 0; j < count; j++) {
  38                 muxreg = &muxregs[j];
  39
  40                 val = pmx_readl(pmx, muxreg->reg);
  41                 val &= ~muxreg->mask;
  42
  43                 if (enable)
  44                         temp = muxreg->val;
  45                 else
  46                         temp = ~muxreg->val;
  47
  48                 val |= muxreg->mask & temp;
  49                 pmx_writel(pmx, val, muxreg->reg);
  50         }
  51 }
  52
  53 static int set_mode(struct spear_pmx *pmx, int mode)
  54 {
  55         struct spear_pmx_mode *pmx_mode = NULL;
  56         int i;
  57         u32 val;
  58
  59         if (!pmx->machdata->pmx_modes || !pmx->machdata->npmx_modes)
  60                 return -EINVAL;
  61
  62         for (i = 0; i < pmx->machdata->npmx_modes; i++) {
  63                 if (pmx->machdata->pmx_modes[i]->mode == (1 << mode)) {
  64                         pmx_mode = pmx->machdata->pmx_modes[i];
  65                         break;
  66                 }
  67         }
  68
  69         if (!pmx_mode)
  70                 return -EINVAL;
  71
  72         val = pmx_readl(pmx, pmx_mode->reg);
  73         val &= ~pmx_mode->mask;
  74         val |= pmx_mode->val;
  75         pmx_writel(pmx, val, pmx_mode->reg);
  76
  77         pmx->machdata->mode = pmx_mode->mode;
  78         dev_info(pmx->dev, "Configured Mode: %s with id: %x\n\n",
  79                         pmx_mode->name ? pmx_mode->name : "no_name",
  80                         pmx_mode->reg);
  81
  82         return 0;
  83 }
  84
  85 void pmx_init_gpio_pingroup_addr(struct spear_gpio_pingroup *gpio_pingroup,
  86                                  unsigned count, u16 reg)
  87 {
  88         int i, j;
  89
  90         for (i = 0; i < count; i++)
  91                 for (j = 0; j < gpio_pingroup[i].nmuxregs; j++)
  92                         gpio_pingroup[i].muxregs[j].reg = reg;
  93 }
  94
  95 void pmx_init_addr(struct spear_pinctrl_machdata *machdata, u16 reg)
  96 {
  97         struct spear_pingroup *pgroup;
  98         struct spear_modemux *modemux;
  99         int i, j, group;
 100
 101         for (group = 0; group < machdata->ngroups; group++) {
 102                 pgroup = machdata->groups[group];
 103
 104                 for (i = 0; i < pgroup->nmodemuxs; i++) {
 105                         modemux = &pgroup->modemuxs[i];
 106
 107                         for (j = 0; j < modemux->nmuxregs; j++)
 108                                 if (modemux->muxregs[j].reg == 0xFFFF)
 109                                         modemux->muxregs[j].reg = reg;
 110                 }
 111         }
 112 }
 113
 114 static int spear_pinctrl_get_groups_cnt(struct pinctrl_dev *pctldev)
 115 {
 116         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 117
 118         return pmx->machdata->ngroups;
 119 }
 120
 121 static const char *spear_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
 122                 unsigned group)
 123 {
 124         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 125
 126         return pmx->machdata->groups[group]->name;
 127 }
 128
 129 static int spear_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
 130                 unsigned group, const unsigned **pins, unsigned *num_pins)
 131 {
 132         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 133
 134         *pins = pmx->machdata->groups[group]->pins;
 135         *num_pins = pmx->machdata->groups[group]->npins;
 136
 137         return 0;
 138 }
 139
 140 static void spear_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
 141                 struct seq_file *s, unsigned offset)
 142 {
 143         seq_printf(s, " " DRIVER_NAME);
 144 }
 145
 146 static int spear_pinctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
 147                                         struct device_node *np_config,
 148                                         struct pinctrl_map **map,
 149                                         unsigned *num_maps)
 150 {
 151         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 152         struct device_node *np;
 153         struct property *prop;
 154         const char *function, *group;
 155         int ret, index = 0, count = 0;
 156
 157         /* calculate number of maps required */
 158         for_each_child_of_node(np_config, np) {
 159                 ret = of_property_read_string(np, "st,function", &function);
 160                 if (ret < 0)
 161                         return ret;
 162
 163                 ret = of_property_count_strings(np, "st,pins");
 164                 if (ret < 0)
 165                         return ret;
 166
 167                 count += ret;
 168         }
 169
 170         if (!count) {
 171                 dev_err(pmx->dev, "No child nodes passed via DT\n");
 172                 return -ENODEV;
 173         }
 174
 175         *map = kzalloc(sizeof(**map) * count, GFP_KERNEL);
 176         if (!*map)
 177                 return -ENOMEM;
 178
 179         for_each_child_of_node(np_config, np) {
 180                 of_property_read_string(np, "st,function", &function);
 181                 of_property_for_each_string(np, "st,pins", prop, group) {
 182                         (*map)[index].type = PIN_MAP_TYPE_MUX_GROUP;
 183                         (*map)[index].data.mux.group = group;
 184                         (*map)[index].data.mux.function = function;
 185                         index++;
 186                 }
 187         }
 188
 189         *num_maps = count;
 190
 191         return 0;
 192 }
 193
 194 static void spear_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
 195                                       struct pinctrl_map *map,
 196                                       unsigned num_maps)
 197 {
 198         kfree(map);
 199 }
 200
 201 static const struct pinctrl_ops spear_pinctrl_ops = {
 202         .get_groups_count = spear_pinctrl_get_groups_cnt,
 203         .get_group_name = spear_pinctrl_get_group_name,
 204         .get_group_pins = spear_pinctrl_get_group_pins,
 205         .pin_dbg_show = spear_pinctrl_pin_dbg_show,
 206         .dt_node_to_map = spear_pinctrl_dt_node_to_map,
 207         .dt_free_map = spear_pinctrl_dt_free_map,
 208 };
 209
 210 static int spear_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
 211 {
 212         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 213
 214         return pmx->machdata->nfunctions;
 215 }
 216
 217 static const char *spear_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
 218                 unsigned function)
 219 {
 220         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 221
 222         return pmx->machdata->functions[function]->name;
 223 }
 224
 225 static int spear_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
 226                 unsigned function, const char *const **groups,
 227                 unsigned * const ngroups)
 228 {
 229         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 230
 231         *groups = pmx->machdata->functions[function]->groups;
 232         *ngroups = pmx->machdata->functions[function]->ngroups;
 233
 234         return 0;
 235 }
 236
 237 static int spear_pinctrl_endisable(struct pinctrl_dev *pctldev,
 238                 unsigned function, unsigned group, bool enable)
 239 {
 240         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 241         const struct spear_pingroup *pgroup;
 242         const struct spear_modemux *modemux;
 243         int i;
 244         bool found = false;
 245
 246         pgroup = pmx->machdata->groups[group];
 247
 248         for (i = 0; i < pgroup->nmodemuxs; i++) {
 249                 modemux = &pgroup->modemuxs[i];
 250
 251                 /* SoC have any modes */
 252                 if (pmx->machdata->modes_supported) {
 253                         if (!(pmx->machdata->mode & modemux->modes))
 254                                 continue;
 255                 }
 256
 257                 found = true;
 258                 muxregs_endisable(pmx, modemux->muxregs, modemux->nmuxregs,
 259                                 enable);
 260         }
 261
 262         if (!found) {
 263                 dev_err(pmx->dev, "pinmux group: %s not supported\n",
 264                                 pgroup->name);
 265                 return -ENODEV;
 266         }
 267
 268         return 0;
 269 }
 270
 271 static int spear_pinctrl_set_mux(struct pinctrl_dev *pctldev, unsigned function,
 272                 unsigned group)
 273 {
 274         return spear_pinctrl_endisable(pctldev, function, group, true);
 275 }
 276
 277 /* gpio with pinmux */
 278 static struct spear_gpio_pingroup *get_gpio_pingroup(struct spear_pmx *pmx,
 279                 unsigned pin)
 280 {
 281         struct spear_gpio_pingroup *gpio_pingroup;
 282         int i, j;
 283
 284         if (!pmx->machdata->gpio_pingroups)
 285                 return NULL;
 286
 287         for (i = 0; i < pmx->machdata->ngpio_pingroups; i++) {
 288                 gpio_pingroup = &pmx->machdata->gpio_pingroups[i];
 289
 290                 for (j = 0; j < gpio_pingroup->npins; j++) {
 291                         if (gpio_pingroup->pins[j] == pin)
 292                                 return gpio_pingroup;
 293                 }
 294         }
 295
 296         return NULL;
 297 }
 298
 299 static int gpio_request_endisable(struct pinctrl_dev *pctldev,
 300                 struct pinctrl_gpio_range *range, unsigned offset, bool enable)
 301 {
 302         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 303         struct spear_pinctrl_machdata *machdata = pmx->machdata;
 304         struct spear_gpio_pingroup *gpio_pingroup;
 305
 306         /*
 307          * Some SoC have configuration options applicable to group of pins,
 308          * rather than a single pin.
 309          */
 310         gpio_pingroup = get_gpio_pingroup(pmx, offset);
 311         if (gpio_pingroup)
 312                 muxregs_endisable(pmx, gpio_pingroup->muxregs,
 313                                 gpio_pingroup->nmuxregs, enable);
 314
 315         /*
 316          * SoC may need some extra configurations, or configurations for single
 317          * pin
 318          */
 319         if (machdata->gpio_request_endisable)
 320                 machdata->gpio_request_endisable(pmx, offset, enable);
 321
 322         return 0;
 323 }
 324
 325 static int gpio_request_enable(struct pinctrl_dev *pctldev,
 326                 struct pinctrl_gpio_range *range, unsigned offset)
 327 {
 328         return gpio_request_endisable(pctldev, range, offset, true);
 329 }
 330
 331 static void gpio_disable_free(struct pinctrl_dev *pctldev,
 332                 struct pinctrl_gpio_range *range, unsigned offset)
 333 {
 334         gpio_request_endisable(pctldev, range, offset, false);
 335 }
 336
 337 static const struct pinmux_ops spear_pinmux_ops = {
 338         .get_functions_count = spear_pinctrl_get_funcs_count,
 339         .get_function_name = spear_pinctrl_get_func_name,
 340         .get_function_groups = spear_pinctrl_get_func_groups,
 341         .set_mux = spear_pinctrl_set_mux,
 342         .gpio_request_enable = gpio_request_enable,
 343         .gpio_disable_free = gpio_disable_free,
 344 };
 345
 346 static struct pinctrl_desc spear_pinctrl_desc = {
 347         .name = DRIVER_NAME,
 348         .pctlops = &spear_pinctrl_ops,
 349         .pmxops = &spear_pinmux_ops,
 350         .owner = THIS_MODULE,
 351 };
 352
 353 int spear_pinctrl_probe(struct platform_device *pdev,
 354                         struct spear_pinctrl_machdata *machdata)
 355 {
 356         struct device_node *np = pdev->dev.of_node;
 357         struct resource *res;
 358         struct spear_pmx *pmx;
 359
 360         if (!machdata)
 361                 return -ENODEV;
 362
 363         pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
 364         if (!pmx) {
 365                 dev_err(&pdev->dev, "Can't alloc spear_pmx\n");
 366                 return -ENOMEM;
 367         }
 368
 369         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 370         pmx->vbase = devm_ioremap_resource(&pdev->dev, res);
 371         if (IS_ERR(pmx->vbase))
 372                 return PTR_ERR(pmx->vbase);
 373
 374         pmx->dev = &pdev->dev;
 375         pmx->machdata = machdata;
 376
 377         /* configure mode, if supported by SoC */
 378         if (machdata->modes_supported) {
 379                 int mode = 0;
 380
 381                 if (of_property_read_u32(np, "st,pinmux-mode", &mode)) {
 382                         dev_err(&pdev->dev, "OF: pinmux mode not passed\n");
 383                         return -EINVAL;
 384                 }
 385
 386                 if (set_mode(pmx, mode)) {
 387                         dev_err(&pdev->dev, "OF: Couldn't configure mode: %x\n",
 388                                         mode);
 389                         return -EINVAL;
 390                 }
 391         }
 392
 393         platform_set_drvdata(pdev, pmx);
 394
 395         spear_pinctrl_desc.pins = machdata->pins;
 396         spear_pinctrl_desc.npins = machdata->npins;
 397
 398         pmx->pctl = pinctrl_register(&spear_pinctrl_desc, &pdev->dev, pmx);
 399         if (!pmx->pctl) {
 400                 dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
 401                 return -ENODEV;
 402         }
 403
 404         return 0;
 405 }
 406
 407 int spear_pinctrl_remove(struct platform_device *pdev)
 408 {
 409         struct spear_pmx *pmx = platform_get_drvdata(pdev);
 410
 411         pinctrl_unregister(pmx->pctl);
 412
 413         return 0;
 414 }