drivers/clk/clk-s2mps11.c

   1 /*
   2  * clk-s2mps11.c - Clock driver for S2MPS11.
   3  *
   4  * Copyright (C) 2013,2014 Samsung Electornics
   5  *
   6  * This program is free software; you can redistribute  it and/or modify it
   7  * under  the terms of  the GNU General  Public License as published by the
   8  * Free Software Foundation;  either version 2 of the  License, or (at your
   9  * option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/err.h>
  20 #include <linux/of.h>
  21 #include <linux/clkdev.h>
  22 #include <linux/regmap.h>
  23 #include <linux/clk-provider.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/mfd/samsung/s2mps11.h>
  26 #include <linux/mfd/samsung/s2mps14.h>
  27 #include <linux/mfd/samsung/s5m8767.h>
  28 #include <linux/mfd/samsung/core.h>
  29
  30 #define s2mps11_name(a) (a->hw.init->name)
  31
  32 static struct clk **clk_table;
  33 static struct clk_onecell_data clk_data;
  34
  35 enum {
  36         S2MPS11_CLK_AP = 0,
  37         S2MPS11_CLK_CP,
  38         S2MPS11_CLK_BT,
  39         S2MPS11_CLKS_NUM,
  40 };
  41
  42 struct s2mps11_clk {
  43         struct sec_pmic_dev *iodev;
  44         struct device_node *clk_np;
  45         struct clk_hw hw;
  46         struct clk *clk;
  47         struct clk_lookup *lookup;
  48         u32 mask;
  49         bool enabled;
  50         unsigned int reg;
  51 };
  52
  53 static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw)
  54 {
  55         return container_of(hw, struct s2mps11_clk, hw);
  56 }
  57
  58 static int s2mps11_clk_prepare(struct clk_hw *hw)
  59 {
  60         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  61         int ret;
  62
  63         ret = regmap_update_bits(s2mps11->iodev->regmap_pmic,
  64                                  s2mps11->reg,
  65                                  s2mps11->mask, s2mps11->mask);
  66         if (!ret)
  67                 s2mps11->enabled = true;
  68
  69         return ret;
  70 }
  71
  72 static void s2mps11_clk_unprepare(struct clk_hw *hw)
  73 {
  74         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  75         int ret;
  76
  77         ret = regmap_update_bits(s2mps11->iodev->regmap_pmic, s2mps11->reg,
  78                            s2mps11->mask, ~s2mps11->mask);
  79
  80         if (!ret)
  81                 s2mps11->enabled = false;
  82 }
  83
  84 static int s2mps11_clk_is_enabled(struct clk_hw *hw)
  85 {
  86         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  87
  88         return s2mps11->enabled;
  89 }
  90
  91 static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw,
  92                                              unsigned long parent_rate)
  93 {
  94         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  95         if (s2mps11->enabled)
  96                 return 32768;
  97         else
  98                 return 0;
  99 }
 100
 101 static struct clk_ops s2mps11_clk_ops = {
 102         .prepare        = s2mps11_clk_prepare,
 103         .unprepare      = s2mps11_clk_unprepare,
 104         .is_enabled     = s2mps11_clk_is_enabled,
 105         .recalc_rate    = s2mps11_clk_recalc_rate,
 106 };
 107
 108 static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = {
 109         [S2MPS11_CLK_AP] = {
 110                 .name = "s2mps11_ap",
 111                 .ops = &s2mps11_clk_ops,
 112                 .flags = CLK_IS_ROOT,
 113         },
 114         [S2MPS11_CLK_CP] = {
 115                 .name = "s2mps11_cp",
 116                 .ops = &s2mps11_clk_ops,
 117                 .flags = CLK_IS_ROOT,
 118         },
 119         [S2MPS11_CLK_BT] = {
 120                 .name = "s2mps11_bt",
 121                 .ops = &s2mps11_clk_ops,
 122                 .flags = CLK_IS_ROOT,
 123         },
 124 };
 125
 126 static struct clk_init_data s2mps14_clks_init[S2MPS11_CLKS_NUM] = {
 127         [S2MPS11_CLK_AP] = {
 128                 .name = "s2mps14_ap",
 129                 .ops = &s2mps11_clk_ops,
 130                 .flags = CLK_IS_ROOT,
 131         },
 132         [S2MPS11_CLK_BT] = {
 133                 .name = "s2mps14_bt",
 134                 .ops = &s2mps11_clk_ops,
 135                 .flags = CLK_IS_ROOT,
 136         },
 137 };
 138
 139 static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev,
 140                 struct clk_init_data *clks_init)
 141 {
 142         struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 143         struct device_node *clk_np;
 144         int i;
 145
 146         if (!iodev->dev->of_node)
 147                 return ERR_PTR(-EINVAL);
 148
 149         clk_np = of_get_child_by_name(iodev->dev->of_node, "clocks");
 150         if (!clk_np) {
 151                 dev_err(&pdev->dev, "could not find clock sub-node\n");
 152                 return ERR_PTR(-EINVAL);
 153         }
 154
 155         for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
 156                 if (!clks_init[i].name)
 157                         continue; /* Skip clocks not present in some devices */
 158                 of_property_read_string_index(clk_np, "clock-output-names", i,
 159                                 &clks_init[i].name);
 160         }
 161
 162         return clk_np;
 163 }
 164
 165 static int s2mps11_clk_probe(struct platform_device *pdev)
 166 {
 167         struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 168         struct s2mps11_clk *s2mps11_clks, *s2mps11_clk;
 169         unsigned int s2mps11_reg;
 170         struct clk_init_data *clks_init;
 171         int i, ret = 0;
 172         u32 val;
 173
 174         s2mps11_clks = devm_kzalloc(&pdev->dev, sizeof(*s2mps11_clk) *
 175                                         S2MPS11_CLKS_NUM, GFP_KERNEL);
 176         if (!s2mps11_clks)
 177                 return -ENOMEM;
 178
 179         s2mps11_clk = s2mps11_clks;
 180
 181         clk_table = devm_kzalloc(&pdev->dev, sizeof(struct clk *) *
 182                                  S2MPS11_CLKS_NUM, GFP_KERNEL);
 183         if (!clk_table)
 184                 return -ENOMEM;
 185
 186         switch(platform_get_device_id(pdev)->driver_data) {
 187         case S2MPS11X:
 188                 s2mps11_reg = S2MPS11_REG_RTC_CTRL;
 189                 clks_init = s2mps11_clks_init;
 190                 break;
 191         case S2MPS14X:
 192                 s2mps11_reg = S2MPS14_REG_RTCCTRL;
 193                 clks_init = s2mps14_clks_init;
 194                 break;
 195         case S5M8767X:
 196                 s2mps11_reg = S5M8767_REG_CTRL1;
 197                 clks_init = s2mps11_clks_init;
 198                 break;
 199         default:
 200                 dev_err(&pdev->dev, "Invalid device type\n");
 201                 return -EINVAL;
 202         };
 203
 204         /* Store clocks of_node in first element of s2mps11_clks array */
 205         s2mps11_clks->clk_np = s2mps11_clk_parse_dt(pdev, clks_init);
 206         if (IS_ERR(s2mps11_clks->clk_np))
 207                 return PTR_ERR(s2mps11_clks->clk_np);
 208
 209         for (i = 0; i < S2MPS11_CLKS_NUM; i++, s2mps11_clk++) {
 210                 if (!clks_init[i].name)
 211                         continue; /* Skip clocks not present in some devices */
 212                 s2mps11_clk->iodev = iodev;
 213                 s2mps11_clk->hw.init = &clks_init[i];
 214                 s2mps11_clk->mask = 1 << i;
 215                 s2mps11_clk->reg = s2mps11_reg;
 216
 217                 ret = regmap_read(s2mps11_clk->iodev->regmap_pmic,
 218                                   s2mps11_clk->reg, &val);
 219                 if (ret < 0)
 220                         goto err_reg;
 221
 222                 s2mps11_clk->enabled = val & s2mps11_clk->mask;
 223
 224                 s2mps11_clk->clk = devm_clk_register(&pdev->dev,
 225                                                         &s2mps11_clk->hw);
 226                 if (IS_ERR(s2mps11_clk->clk)) {
 227                         dev_err(&pdev->dev, "Fail to register : %s\n",
 228                                                 s2mps11_name(s2mps11_clk));
 229                         ret = PTR_ERR(s2mps11_clk->clk);
 230                         goto err_reg;
 231                 }
 232
 233                 s2mps11_clk->lookup = clkdev_alloc(s2mps11_clk->clk,
 234                                         s2mps11_name(s2mps11_clk), NULL);
 235                 if (!s2mps11_clk->lookup) {
 236                         ret = -ENOMEM;
 237                         goto err_lup;
 238                 }
 239
 240                 clkdev_add(s2mps11_clk->lookup);
 241         }
 242
 243         for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
 244                 /* Skip clocks not present on S2MPS14 */
 245                 if (!clks_init[i].name)
 246                         continue;
 247                 clk_table[i] = s2mps11_clks[i].clk;
 248         }
 249
 250         clk_data.clks = clk_table;
 251         clk_data.clk_num = S2MPS11_CLKS_NUM;
 252         of_clk_add_provider(s2mps11_clks->clk_np, of_clk_src_onecell_get,
 253                         &clk_data);
 254
 255         platform_set_drvdata(pdev, s2mps11_clks);
 256
 257         return ret;
 258 err_lup:
 259         devm_clk_unregister(&pdev->dev, s2mps11_clk->clk);
 260 err_reg:
 261         while (s2mps11_clk > s2mps11_clks) {
 262                 if (s2mps11_clk->lookup) {
 263                         clkdev_drop(s2mps11_clk->lookup);
 264                         devm_clk_unregister(&pdev->dev, s2mps11_clk->clk);
 265                 }
 266                 s2mps11_clk--;
 267         }
 268
 269         return ret;
 270 }
 271
 272 static int s2mps11_clk_remove(struct platform_device *pdev)
 273 {
 274         struct s2mps11_clk *s2mps11_clks = platform_get_drvdata(pdev);
 275         int i;
 276
 277         of_clk_del_provider(s2mps11_clks[0].clk_np);
 278         /* Drop the reference obtained in s2mps11_clk_parse_dt */
 279         of_node_put(s2mps11_clks[0].clk_np);
 280
 281         for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
 282                 /* Skip clocks not present on S2MPS14 */
 283                 if (!s2mps11_clks[i].lookup)
 284                         continue;
 285                 clkdev_drop(s2mps11_clks[i].lookup);
 286         }
 287
 288         return 0;
 289 }
 290
 291 static const struct platform_device_id s2mps11_clk_id[] = {
 292         { "s2mps11-clk", S2MPS11X},
 293         { "s2mps14-clk", S2MPS14X},
 294         { "s5m8767-clk", S5M8767X},
 295         { },
 296 };
 297 MODULE_DEVICE_TABLE(platform, s2mps11_clk_id);
 298
 299 static struct platform_driver s2mps11_clk_driver = {
 300         .driver = {
 301                 .name  = "s2mps11-clk",
 302                 .owner = THIS_MODULE,
 303         },
 304         .probe = s2mps11_clk_probe,
 305         .remove = s2mps11_clk_remove,
 306         .id_table = s2mps11_clk_id,
 307 };
 308
 309 static int __init s2mps11_clk_init(void)
 310 {
 311         return platform_driver_register(&s2mps11_clk_driver);
 312 }
 313 subsys_initcall(s2mps11_clk_init);
 314
 315 static void __init s2mps11_clk_cleanup(void)
 316 {
 317         platform_driver_unregister(&s2mps11_clk_driver);
 318 }
 319 module_exit(s2mps11_clk_cleanup);
 320
 321 MODULE_DESCRIPTION("S2MPS11 Clock Driver");
 322 MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>");
 323 MODULE_LICENSE("GPL");