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/io.h>
  18 #include <linux/module.h>
  19 #include <linux/of.h>
  20 #include <linux/of_address.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 inline u32 pmx_readl(struct spear_pmx *pmx, u32 reg)
  32 {
  33         return readl_relaxed(pmx->vbase + reg);
  34 }
  35
  36 static inline void pmx_writel(struct spear_pmx *pmx, u32 val, u32 reg)
  37 {
  38         writel_relaxed(val, pmx->vbase + reg);
  39 }
  40
  41 static int set_mode(struct spear_pmx *pmx, int mode)
  42 {
  43         struct spear_pmx_mode *pmx_mode = NULL;
  44         int i;
  45         u32 val;
  46
  47         if (!pmx->machdata->pmx_modes || !pmx->machdata->npmx_modes)
  48                 return -EINVAL;
  49
  50         for (i = 0; i < pmx->machdata->npmx_modes; i++) {
  51                 if (pmx->machdata->pmx_modes[i]->mode == (1 << mode)) {
  52                         pmx_mode = pmx->machdata->pmx_modes[i];
  53                         break;
  54                 }
  55         }
  56
  57         if (!pmx_mode)
  58                 return -EINVAL;
  59
  60         val = pmx_readl(pmx, pmx_mode->reg);
  61         val &= ~pmx_mode->mask;
  62         val |= pmx_mode->val;
  63         pmx_writel(pmx, val, pmx_mode->reg);
  64
  65         pmx->machdata->mode = pmx_mode->mode;
  66         dev_info(pmx->dev, "Configured Mode: %s with id: %x\n\n",
  67                         pmx_mode->name ? pmx_mode->name : "no_name",
  68                         pmx_mode->reg);
  69
  70         return 0;
  71 }
  72
  73 void __devinit pmx_init_addr(struct spear_pinctrl_machdata *machdata, u16 reg)
  74 {
  75         struct spear_pingroup *pgroup;
  76         struct spear_modemux *modemux;
  77         int i, j, group;
  78
  79         for (group = 0; group < machdata->ngroups; group++) {
  80                 pgroup = machdata->groups[group];
  81
  82                 for (i = 0; i < pgroup->nmodemuxs; i++) {
  83                         modemux = &pgroup->modemuxs[i];
  84
  85                         for (j = 0; j < modemux->nmuxregs; j++)
  86                                 if (modemux->muxregs[j].reg == 0xFFFF)
  87                                         modemux->muxregs[j].reg = reg;
  88                 }
  89         }
  90 }
  91
  92 static int spear_pinctrl_get_groups_cnt(struct pinctrl_dev *pctldev)
  93 {
  94         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
  95
  96         return pmx->machdata->ngroups;
  97 }
  98
  99 static const char *spear_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
 100                 unsigned group)
 101 {
 102         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 103
 104         return pmx->machdata->groups[group]->name;
 105 }
 106
 107 static int spear_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
 108                 unsigned group, const unsigned **pins, unsigned *num_pins)
 109 {
 110         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 111
 112         *pins = pmx->machdata->groups[group]->pins;
 113         *num_pins = pmx->machdata->groups[group]->npins;
 114
 115         return 0;
 116 }
 117
 118 static void spear_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
 119                 struct seq_file *s, unsigned offset)
 120 {
 121         seq_printf(s, " " DRIVER_NAME);
 122 }
 123
 124 int spear_pinctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
 125                                  struct device_node *np_config,
 126                                  struct pinctrl_map **map, unsigned *num_maps)
 127 {
 128         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 129         struct device_node *np;
 130         struct property *prop;
 131         const char *function, *group;
 132         int ret, index = 0, count = 0;
 133
 134         /* calculate number of maps required */
 135         for_each_child_of_node(np_config, np) {
 136                 ret = of_property_read_string(np, "st,function", &function);
 137                 if (ret < 0)
 138                         return ret;
 139
 140                 ret = of_property_count_strings(np, "st,pins");
 141                 if (ret < 0)
 142                         return ret;
 143
 144                 count += ret;
 145         }
 146
 147         if (!count) {
 148                 dev_err(pmx->dev, "No child nodes passed via DT\n");
 149                 return -ENODEV;
 150         }
 151
 152         *map = kzalloc(sizeof(**map) * count, GFP_KERNEL);
 153         if (!*map)
 154                 return -ENOMEM;
 155
 156         for_each_child_of_node(np_config, np) {
 157                 of_property_read_string(np, "st,function", &function);
 158                 of_property_for_each_string(np, "st,pins", prop, group) {
 159                         (*map)[index].type = PIN_MAP_TYPE_MUX_GROUP;
 160                         (*map)[index].data.mux.group = group;
 161                         (*map)[index].data.mux.function = function;
 162                         index++;
 163                 }
 164         }
 165
 166         *num_maps = count;
 167
 168         return 0;
 169 }
 170
 171 void spear_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
 172                 struct pinctrl_map *map, unsigned num_maps)
 173 {
 174         kfree(map);
 175 }
 176
 177 static struct pinctrl_ops spear_pinctrl_ops = {
 178         .get_groups_count = spear_pinctrl_get_groups_cnt,
 179         .get_group_name = spear_pinctrl_get_group_name,
 180         .get_group_pins = spear_pinctrl_get_group_pins,
 181         .pin_dbg_show = spear_pinctrl_pin_dbg_show,
 182         .dt_node_to_map = spear_pinctrl_dt_node_to_map,
 183         .dt_free_map = spear_pinctrl_dt_free_map,
 184 };
 185
 186 static int spear_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
 187 {
 188         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 189
 190         return pmx->machdata->nfunctions;
 191 }
 192
 193 static const char *spear_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
 194                 unsigned function)
 195 {
 196         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 197
 198         return pmx->machdata->functions[function]->name;
 199 }
 200
 201 static int spear_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
 202                 unsigned function, const char *const **groups,
 203                 unsigned * const ngroups)
 204 {
 205         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 206
 207         *groups = pmx->machdata->functions[function]->groups;
 208         *ngroups = pmx->machdata->functions[function]->ngroups;
 209
 210         return 0;
 211 }
 212
 213 static int spear_pinctrl_endisable(struct pinctrl_dev *pctldev,
 214                 unsigned function, unsigned group, bool enable)
 215 {
 216         struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 217         const struct spear_pingroup *pgroup;
 218         const struct spear_modemux *modemux;
 219         struct spear_muxreg *muxreg;
 220         u32 val, temp;
 221         int i, j;
 222         bool found = false;
 223
 224         pgroup = pmx->machdata->groups[group];
 225
 226         for (i = 0; i < pgroup->nmodemuxs; i++) {
 227                 modemux = &pgroup->modemuxs[i];
 228
 229                 /* SoC have any modes */
 230                 if (pmx->machdata->modes_supported) {
 231                         if (!(pmx->machdata->mode & modemux->modes))
 232                                 continue;
 233                 }
 234
 235                 found = true;
 236                 for (j = 0; j < modemux->nmuxregs; j++) {
 237                         muxreg = &modemux->muxregs[j];
 238
 239                         val = pmx_readl(pmx, muxreg->reg);
 240                         val &= ~muxreg->mask;
 241
 242                         if (enable)
 243                                 temp = muxreg->val;
 244                         else
 245                                 temp = ~muxreg->val;
 246
 247                         val |= temp;
 248                         pmx_writel(pmx, val, muxreg->reg);
 249                 }
 250         }
 251
 252         if (!found) {
 253                 dev_err(pmx->dev, "pinmux group: %s not supported\n",
 254                                 pgroup->name);
 255                 return -ENODEV;
 256         }
 257
 258         return 0;
 259 }
 260
 261 static int spear_pinctrl_enable(struct pinctrl_dev *pctldev, unsigned function,
 262                 unsigned group)
 263 {
 264         return spear_pinctrl_endisable(pctldev, function, group, true);
 265 }
 266
 267 static void spear_pinctrl_disable(struct pinctrl_dev *pctldev,
 268                 unsigned function, unsigned group)
 269 {
 270         spear_pinctrl_endisable(pctldev, function, group, false);
 271 }
 272
 273 static struct pinmux_ops spear_pinmux_ops = {
 274         .get_functions_count = spear_pinctrl_get_funcs_count,
 275         .get_function_name = spear_pinctrl_get_func_name,
 276         .get_function_groups = spear_pinctrl_get_func_groups,
 277         .enable = spear_pinctrl_enable,
 278         .disable = spear_pinctrl_disable,
 279 };
 280
 281 static struct pinctrl_desc spear_pinctrl_desc = {
 282         .name = DRIVER_NAME,
 283         .pctlops = &spear_pinctrl_ops,
 284         .pmxops = &spear_pinmux_ops,
 285         .owner = THIS_MODULE,
 286 };
 287
 288 int __devinit spear_pinctrl_probe(struct platform_device *pdev,
 289                 struct spear_pinctrl_machdata *machdata)
 290 {
 291         struct device_node *np = pdev->dev.of_node;
 292         struct resource *res;
 293         struct spear_pmx *pmx;
 294
 295         if (!machdata)
 296                 return -ENODEV;
 297
 298         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 299         if (!res)
 300                 return -EINVAL;
 301
 302         pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
 303         if (!pmx) {
 304                 dev_err(&pdev->dev, "Can't alloc spear_pmx\n");
 305                 return -ENOMEM;
 306         }
 307
 308         pmx->vbase = devm_ioremap(&pdev->dev, res->start, resource_size(res));
 309         if (!pmx->vbase) {
 310                 dev_err(&pdev->dev, "Couldn't ioremap at index 0\n");
 311                 return -ENODEV;
 312         }
 313
 314         pmx->dev = &pdev->dev;
 315         pmx->machdata = machdata;
 316
 317         /* configure mode, if supported by SoC */
 318         if (machdata->modes_supported) {
 319                 int mode = 0;
 320
 321                 if (of_property_read_u32(np, "st,pinmux-mode", &mode)) {
 322                         dev_err(&pdev->dev, "OF: pinmux mode not passed\n");
 323                         return -EINVAL;
 324                 }
 325
 326                 if (set_mode(pmx, mode)) {
 327                         dev_err(&pdev->dev, "OF: Couldn't configure mode: %x\n",
 328                                         mode);
 329                         return -EINVAL;
 330                 }
 331         }
 332
 333         platform_set_drvdata(pdev, pmx);
 334
 335         spear_pinctrl_desc.pins = machdata->pins;
 336         spear_pinctrl_desc.npins = machdata->npins;
 337
 338         pmx->pctl = pinctrl_register(&spear_pinctrl_desc, &pdev->dev, pmx);
 339         if (!pmx->pctl) {
 340                 dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
 341                 return -ENODEV;
 342         }
 343
 344         return 0;
 345 }
 346
 347 int __devexit spear_pinctrl_remove(struct platform_device *pdev)
 348 {
 349         struct spear_pmx *pmx = platform_get_drvdata(pdev);
 350
 351         pinctrl_unregister(pmx->pctl);
 352
 353         return 0;
 354 }