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 device_node *clk_np;
  48         struct clk_hw hw;
  49         struct clk *clk;
  50         struct clk_lookup *lookup;
  51         u32 mask;
  52         bool enabled;
  53         unsigned int reg;
  54 };
  55
  56 static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw)
  57 {
  58         return container_of(hw, struct s2mps11_clk, hw);
  59 }
  60
  61 static int s2mps11_clk_prepare(struct clk_hw *hw)
  62 {
  63         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  64         int ret;
  65
  66         ret = regmap_update_bits(s2mps11->iodev->regmap_pmic,
  67                                  s2mps11->reg,
  68                                  s2mps11->mask, s2mps11->mask);
  69         if (!ret)
  70                 s2mps11->enabled = true;
  71
  72         return ret;
  73 }
  74
  75 static void s2mps11_clk_unprepare(struct clk_hw *hw)
  76 {
  77         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  78         int ret;
  79
  80         ret = regmap_update_bits(s2mps11->iodev->regmap_pmic, s2mps11->reg,
  81                            s2mps11->mask, ~s2mps11->mask);
  82
  83         if (!ret)
  84                 s2mps11->enabled = false;
  85 }
  86
  87 static int s2mps11_clk_is_enabled(struct clk_hw *hw)
  88 {
  89         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  90
  91         return s2mps11->enabled;
  92 }
  93
  94 static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw,
  95                                              unsigned long parent_rate)
  96 {
  97         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  98         if (s2mps11->enabled)
  99                 return 32768;
 100         else
 101                 return 0;
 102 }
 103
 104 static struct clk_ops s2mps11_clk_ops = {
 105         .prepare        = s2mps11_clk_prepare,
 106         .unprepare      = s2mps11_clk_unprepare,
 107         .is_enabled     = s2mps11_clk_is_enabled,
 108         .recalc_rate    = s2mps11_clk_recalc_rate,
 109 };
 110
 111 static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = {
 112         [S2MPS11_CLK_AP] = {
 113                 .name = "s2mps11_ap",
 114                 .ops = &s2mps11_clk_ops,
 115                 .flags = CLK_IS_ROOT,
 116         },
 117         [S2MPS11_CLK_CP] = {
 118                 .name = "s2mps11_cp",
 119                 .ops = &s2mps11_clk_ops,
 120                 .flags = CLK_IS_ROOT,
 121         },
 122         [S2MPS11_CLK_BT] = {
 123                 .name = "s2mps11_bt",
 124                 .ops = &s2mps11_clk_ops,
 125                 .flags = CLK_IS_ROOT,
 126         },
 127 };
 128
 129 static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev)
 130 {
 131         struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 132         struct device_node *clk_np;
 133         int i;
 134
 135         if (!iodev->dev->of_node)
 136                 return ERR_PTR(-EINVAL);
 137
 138         clk_np = of_get_child_by_name(iodev->dev->of_node, "clocks");
 139         if (!clk_np) {
 140                 dev_err(&pdev->dev, "could not find clock sub-node\n");
 141                 return ERR_PTR(-EINVAL);
 142         }
 143
 144         for (i = 0; i < S2MPS11_CLKS_NUM; i++)
 145                 of_property_read_string_index(clk_np, "clock-output-names", i,
 146                                 &s2mps11_clks_init[i].name);
 147
 148         return clk_np;
 149 }
 150
 151 static int s2mps11_clk_probe(struct platform_device *pdev)
 152 {
 153         struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 154         struct s2mps11_clk *s2mps11_clks, *s2mps11_clk;
 155         unsigned int s2mps11_reg;
 156         int i, ret = 0;
 157         u32 val;
 158
 159         s2mps11_clks = devm_kzalloc(&pdev->dev, sizeof(*s2mps11_clk) *
 160                                         S2MPS11_CLKS_NUM, GFP_KERNEL);
 161         if (!s2mps11_clks)
 162                 return -ENOMEM;
 163
 164         s2mps11_clk = s2mps11_clks;
 165
 166         clk_table = devm_kzalloc(&pdev->dev, sizeof(struct clk *) *
 167                                  S2MPS11_CLKS_NUM, GFP_KERNEL);
 168         if (!clk_table)
 169                 return -ENOMEM;
 170
 171         /* Store clocks of_node in first element of s2mps11_clks array */
 172         s2mps11_clks->clk_np = s2mps11_clk_parse_dt(pdev);
 173         if (IS_ERR(s2mps11_clks->clk_np))
 174                 return PTR_ERR(s2mps11_clks->clk_np);
 175
 176         switch(platform_get_device_id(pdev)->driver_data) {
 177         case S2MPS11X:
 178                 s2mps11_reg = S2MPS11_REG_RTC_CTRL;
 179                 break;
 180         case S5M8767X:
 181                 s2mps11_reg = S5M8767_REG_CTRL1;
 182                 break;
 183         default:
 184                 dev_err(&pdev->dev, "Invalid device type\n");
 185                 return -EINVAL;
 186         };
 187
 188         for (i = 0; i < S2MPS11_CLKS_NUM; i++, s2mps11_clk++) {
 189                 s2mps11_clk->iodev = iodev;
 190                 s2mps11_clk->hw.init = &s2mps11_clks_init[i];
 191                 s2mps11_clk->mask = 1 << i;
 192                 s2mps11_clk->reg = s2mps11_reg;
 193
 194                 ret = regmap_read(s2mps11_clk->iodev->regmap_pmic,
 195                                   s2mps11_clk->reg, &val);
 196                 if (ret < 0)
 197                         goto err_reg;
 198
 199                 s2mps11_clk->enabled = val & s2mps11_clk->mask;
 200
 201                 s2mps11_clk->clk = devm_clk_register(&pdev->dev,
 202                                                         &s2mps11_clk->hw);
 203                 if (IS_ERR(s2mps11_clk->clk)) {
 204                         dev_err(&pdev->dev, "Fail to register : %s\n",
 205                                                 s2mps11_name(s2mps11_clk));
 206                         ret = PTR_ERR(s2mps11_clk->clk);
 207                         goto err_reg;
 208                 }
 209
 210                 s2mps11_clk->lookup = devm_kzalloc(&pdev->dev,
 211                                         sizeof(struct clk_lookup), GFP_KERNEL);
 212                 if (!s2mps11_clk->lookup) {
 213                         ret = -ENOMEM;
 214                         goto err_lup;
 215                 }
 216
 217                 s2mps11_clk->lookup->con_id = s2mps11_name(s2mps11_clk);
 218                 s2mps11_clk->lookup->clk = s2mps11_clk->clk;
 219
 220                 clkdev_add(s2mps11_clk->lookup);
 221         }
 222
 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(s2mps11_clks->clk_np, of_clk_src_onecell_get,
 229                         &clk_data);
 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         of_clk_del_provider(s2mps11_clks[0].clk_np);
 254         /* Drop the reference obtained in s2mps11_clk_parse_dt */
 255         of_node_put(s2mps11_clks[0].clk_np);
 256
 257         for (i = 0; i < S2MPS11_CLKS_NUM; i++)
 258                 clkdev_drop(s2mps11_clks[i].lookup);
 259
 260         return 0;
 261 }
 262
 263 static const struct platform_device_id s2mps11_clk_id[] = {
 264         { "s2mps11-clk", S2MPS11X},
 265         { "s5m8767-clk", S5M8767X},
 266         { },
 267 };
 268 MODULE_DEVICE_TABLE(platform, s2mps11_clk_id);
 269
 270 static struct platform_driver s2mps11_clk_driver = {
 271         .driver = {
 272                 .name  = "s2mps11-clk",
 273                 .owner = THIS_MODULE,
 274         },
 275         .probe = s2mps11_clk_probe,
 276         .remove = s2mps11_clk_remove,
 277         .id_table = s2mps11_clk_id,
 278 };
 279
 280 static int __init s2mps11_clk_init(void)
 281 {
 282         return platform_driver_register(&s2mps11_clk_driver);
 283 }
 284 subsys_initcall(s2mps11_clk_init);
 285
 286 static void __init s2mps11_clk_cleanup(void)
 287 {
 288         platform_driver_unregister(&s2mps11_clk_driver);
 289 }
 290 module_exit(s2mps11_clk_cleanup);
 291
 292 MODULE_DESCRIPTION("S2MPS11 Clock Driver");
 293 MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>");
 294 MODULE_LICENSE("GPL");