drivers/clk/clk-s2mps11.c

   1 /*
   2  * clk-s2mps11.c - Clock driver for S2MPS11.
   3  *
   4  * Copyright (C) 2013 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  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 #include <linux/module.h>
  23 #include <linux/err.h>
  24 #include <linux/of.h>
  25 #include <linux/clkdev.h>
  26 #include <linux/regmap.h>
  27 #include <linux/clk-provider.h>
  28 #include <linux/platform_device.h>
  29 #include <linux/mfd/samsung/s2mps11.h>
  30 #include <linux/mfd/samsung/s5m8767.h>
  31 #include <linux/mfd/samsung/core.h>
  32
  33 #define s2mps11_name(a) (a->hw.init->name)
  34
  35 static struct clk **clk_table;
  36 static struct clk_onecell_data clk_data;
  37
  38 enum {
  39         S2MPS11_CLK_AP = 0,
  40         S2MPS11_CLK_CP,
  41         S2MPS11_CLK_BT,
  42         S2MPS11_CLKS_NUM,
  43 };
  44
  45 struct s2mps11_clk {
  46         struct sec_pmic_dev *iodev;
  47         struct clk_hw hw;
  48         struct clk *clk;
  49         struct clk_lookup *lookup;
  50         u32 mask;
  51         bool enabled;
  52         unsigned int reg;
  53 };
  54
  55 static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw)
  56 {
  57         return container_of(hw, struct s2mps11_clk, hw);
  58 }
  59
  60 static int s2mps11_clk_prepare(struct clk_hw *hw)
  61 {
  62         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  63         int ret;
  64
  65         ret = regmap_update_bits(s2mps11->iodev->regmap_pmic,
  66                                  s2mps11->reg,
  67                                  s2mps11->mask, s2mps11->mask);
  68         if (!ret)
  69                 s2mps11->enabled = true;
  70
  71         return ret;
  72 }
  73
  74 static void s2mps11_clk_unprepare(struct clk_hw *hw)
  75 {
  76         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  77         int ret;
  78
  79         ret = regmap_update_bits(s2mps11->iodev->regmap_pmic, s2mps11->reg,
  80                            s2mps11->mask, ~s2mps11->mask);
  81
  82         if (!ret)
  83                 s2mps11->enabled = false;
  84 }
  85
  86 static int s2mps11_clk_is_enabled(struct clk_hw *hw)
  87 {
  88         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  89
  90         return s2mps11->enabled;
  91 }
  92
  93 static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw,
  94                                              unsigned long parent_rate)
  95 {
  96         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  97         if (s2mps11->enabled)
  98                 return 32768;
  99         else
 100                 return 0;
 101 }
 102
 103 static struct clk_ops s2mps11_clk_ops = {
 104         .prepare        = s2mps11_clk_prepare,
 105         .unprepare      = s2mps11_clk_unprepare,
 106         .is_enabled     = s2mps11_clk_is_enabled,
 107         .recalc_rate    = s2mps11_clk_recalc_rate,
 108 };
 109
 110 static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = {
 111         [S2MPS11_CLK_AP] = {
 112                 .name = "s2mps11_ap",
 113                 .ops = &s2mps11_clk_ops,
 114                 .flags = CLK_IS_ROOT,
 115         },
 116         [S2MPS11_CLK_CP] = {
 117                 .name = "s2mps11_cp",
 118                 .ops = &s2mps11_clk_ops,
 119                 .flags = CLK_IS_ROOT,
 120         },
 121         [S2MPS11_CLK_BT] = {
 122                 .name = "s2mps11_bt",
 123                 .ops = &s2mps11_clk_ops,
 124                 .flags = CLK_IS_ROOT,
 125         },
 126 };
 127
 128 static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev)
 129 {
 130         struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 131         struct device_node *clk_np;
 132         int i;
 133
 134         if (!iodev->dev->of_node)
 135                 return ERR_PTR(-EINVAL);
 136
 137         clk_np = of_get_child_by_name(iodev->dev->of_node, "clocks");
 138         if (!clk_np) {
 139                 dev_err(&pdev->dev, "could not find clock sub-node\n");
 140                 return ERR_PTR(-EINVAL);
 141         }
 142
 143         clk_table = devm_kzalloc(&pdev->dev, sizeof(struct clk *) *
 144                                  S2MPS11_CLKS_NUM, GFP_KERNEL);
 145         if (!clk_table)
 146                 return ERR_PTR(-ENOMEM);
 147
 148         for (i = 0; i < S2MPS11_CLKS_NUM; i++)
 149                 of_property_read_string_index(clk_np, "clock-output-names", i,
 150                                 &s2mps11_clks_init[i].name);
 151
 152         return clk_np;
 153 }
 154
 155 static int s2mps11_clk_probe(struct platform_device *pdev)
 156 {
 157         struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 158         struct s2mps11_clk *s2mps11_clks, *s2mps11_clk;
 159         struct device_node *clk_np = NULL;
 160         unsigned int s2mps11_reg;
 161         int i, ret = 0;
 162         u32 val;
 163
 164         s2mps11_clks = devm_kzalloc(&pdev->dev, sizeof(*s2mps11_clk) *
 165                                         S2MPS11_CLKS_NUM, GFP_KERNEL);
 166         if (!s2mps11_clks)
 167                 return -ENOMEM;
 168
 169         s2mps11_clk = s2mps11_clks;
 170
 171         clk_np = s2mps11_clk_parse_dt(pdev);
 172         if (IS_ERR(clk_np))
 173                 return PTR_ERR(clk_np);
 174
 175         switch(platform_get_device_id(pdev)->driver_data) {
 176         case S2MPS11X:
 177                 s2mps11_reg = S2MPS11_REG_RTC_CTRL;
 178                 break;
 179         case S5M8767X:
 180                 s2mps11_reg = S5M8767_REG_CTRL1;
 181                 break;
 182         default:
 183                 dev_err(&pdev->dev, "Invalid device type\n");
 184                 return -EINVAL;
 185         };
 186
 187         for (i = 0; i < S2MPS11_CLKS_NUM; i++, s2mps11_clk++) {
 188                 s2mps11_clk->iodev = iodev;
 189                 s2mps11_clk->hw.init = &s2mps11_clks_init[i];
 190                 s2mps11_clk->mask = 1 << i;
 191                 s2mps11_clk->reg = s2mps11_reg;
 192
 193                 ret = regmap_read(s2mps11_clk->iodev->regmap_pmic,
 194                                   s2mps11_clk->reg, &val);
 195                 if (ret < 0)
 196                         goto err_reg;
 197
 198                 s2mps11_clk->enabled = val & s2mps11_clk->mask;
 199
 200                 s2mps11_clk->clk = devm_clk_register(&pdev->dev,
 201                                                         &s2mps11_clk->hw);
 202                 if (IS_ERR(s2mps11_clk->clk)) {
 203                         dev_err(&pdev->dev, "Fail to register : %s\n",
 204                                                 s2mps11_name(s2mps11_clk));
 205                         ret = PTR_ERR(s2mps11_clk->clk);
 206                         goto err_reg;
 207                 }
 208
 209                 s2mps11_clk->lookup = devm_kzalloc(&pdev->dev,
 210                                         sizeof(struct clk_lookup), GFP_KERNEL);
 211                 if (!s2mps11_clk->lookup) {
 212                         ret = -ENOMEM;
 213                         goto err_lup;
 214                 }
 215
 216                 s2mps11_clk->lookup->con_id = s2mps11_name(s2mps11_clk);
 217                 s2mps11_clk->lookup->clk = s2mps11_clk->clk;
 218
 219                 clkdev_add(s2mps11_clk->lookup);
 220         }
 221
 222         if (clk_table) {
 223                 for (i = 0; i < S2MPS11_CLKS_NUM; i++)
 224                         clk_table[i] = s2mps11_clks[i].clk;
 225
 226                 clk_data.clks = clk_table;
 227                 clk_data.clk_num = S2MPS11_CLKS_NUM;
 228                 of_clk_add_provider(clk_np, of_clk_src_onecell_get, &clk_data);
 229         }
 230
 231         platform_set_drvdata(pdev, s2mps11_clks);
 232
 233         return ret;
 234 err_lup:
 235         devm_clk_unregister(&pdev->dev, s2mps11_clk->clk);
 236 err_reg:
 237         while (s2mps11_clk > s2mps11_clks) {
 238                 if (s2mps11_clk->lookup) {
 239                         clkdev_drop(s2mps11_clk->lookup);
 240                         devm_clk_unregister(&pdev->dev, s2mps11_clk->clk);
 241                 }
 242                 s2mps11_clk--;
 243         }
 244
 245         return ret;
 246 }
 247
 248 static int s2mps11_clk_remove(struct platform_device *pdev)
 249 {
 250         struct s2mps11_clk *s2mps11_clks = platform_get_drvdata(pdev);
 251         int i;
 252
 253         for (i = 0; i < S2MPS11_CLKS_NUM; i++)
 254                 clkdev_drop(s2mps11_clks[i].lookup);
 255
 256         return 0;
 257 }
 258
 259 static const struct platform_device_id s2mps11_clk_id[] = {
 260         { "s2mps11-clk", S2MPS11X},
 261         { "s5m8767-clk", S5M8767X},
 262         { },
 263 };
 264 MODULE_DEVICE_TABLE(platform, s2mps11_clk_id);
 265
 266 static struct platform_driver s2mps11_clk_driver = {
 267         .driver = {
 268                 .name  = "s2mps11-clk",
 269                 .owner = THIS_MODULE,
 270         },
 271         .probe = s2mps11_clk_probe,
 272         .remove = s2mps11_clk_remove,
 273         .id_table = s2mps11_clk_id,
 274 };
 275
 276 static int __init s2mps11_clk_init(void)
 277 {
 278         return platform_driver_register(&s2mps11_clk_driver);
 279 }
 280 subsys_initcall(s2mps11_clk_init);
 281
 282 static void __init s2mps11_clk_cleanup(void)
 283 {
 284         platform_driver_unregister(&s2mps11_clk_driver);
 285 }
 286 module_exit(s2mps11_clk_cleanup);
 287
 288 MODULE_DESCRIPTION("S2MPS11 Clock Driver");
 289 MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>");
 290 MODULE_LICENSE("GPL");