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/s2mps13.h>
  27 #include <linux/mfd/samsung/s2mps14.h>
  28 #include <linux/mfd/samsung/s5m8767.h>
  29 #include <linux/mfd/samsung/core.h>
  30
  31 enum {
  32         S2MPS11_CLK_AP = 0,
  33         S2MPS11_CLK_CP,
  34         S2MPS11_CLK_BT,
  35         S2MPS11_CLKS_NUM,
  36 };
  37
  38 struct s2mps11_clk {
  39         struct sec_pmic_dev *iodev;
  40         struct device_node *clk_np;
  41         struct clk_hw hw;
  42         struct clk *clk;
  43         struct clk_lookup *lookup;
  44         u32 mask;
  45         unsigned int reg;
  46 };
  47
  48 static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw)
  49 {
  50         return container_of(hw, struct s2mps11_clk, hw);
  51 }
  52
  53 static int s2mps11_clk_prepare(struct clk_hw *hw)
  54 {
  55         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  56
  57         return regmap_update_bits(s2mps11->iodev->regmap_pmic,
  58                                  s2mps11->reg,
  59                                  s2mps11->mask, s2mps11->mask);
  60 }
  61
  62 static void s2mps11_clk_unprepare(struct clk_hw *hw)
  63 {
  64         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  65
  66         regmap_update_bits(s2mps11->iodev->regmap_pmic, s2mps11->reg,
  67                            s2mps11->mask, ~s2mps11->mask);
  68 }
  69
  70 static int s2mps11_clk_is_prepared(struct clk_hw *hw)
  71 {
  72         int ret;
  73         u32 val;
  74         struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
  75
  76         ret = regmap_read(s2mps11->iodev->regmap_pmic,
  77                                 s2mps11->reg, &val);
  78         if (ret < 0)
  79                 return -EINVAL;
  80
  81         return val & s2mps11->mask;
  82 }
  83
  84 static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw,
  85                                              unsigned long parent_rate)
  86 {
  87         return 32768;
  88 }
  89
  90 static struct clk_ops s2mps11_clk_ops = {
  91         .prepare        = s2mps11_clk_prepare,
  92         .unprepare      = s2mps11_clk_unprepare,
  93         .is_prepared    = s2mps11_clk_is_prepared,
  94         .recalc_rate    = s2mps11_clk_recalc_rate,
  95 };
  96
  97 /* This s2mps11_clks_init tructure is common to s2mps11, s2mps13 and s2mps14 */
  98 static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = {
  99         [S2MPS11_CLK_AP] = {
 100                 .name = "s2mps11_ap",
 101                 .ops = &s2mps11_clk_ops,
 102                 .flags = CLK_IS_ROOT,
 103         },
 104         [S2MPS11_CLK_CP] = {
 105                 .name = "s2mps11_cp",
 106                 .ops = &s2mps11_clk_ops,
 107                 .flags = CLK_IS_ROOT,
 108         },
 109         [S2MPS11_CLK_BT] = {
 110                 .name = "s2mps11_bt",
 111                 .ops = &s2mps11_clk_ops,
 112                 .flags = CLK_IS_ROOT,
 113         },
 114 };
 115
 116 static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev,
 117                 struct clk_init_data *clks_init)
 118 {
 119         struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 120         struct device_node *clk_np;
 121         int i;
 122
 123         if (!iodev->dev->of_node)
 124                 return ERR_PTR(-EINVAL);
 125
 126         clk_np = of_get_child_by_name(iodev->dev->of_node, "clocks");
 127         if (!clk_np) {
 128                 dev_err(&pdev->dev, "could not find clock sub-node\n");
 129                 return ERR_PTR(-EINVAL);
 130         }
 131
 132         for (i = 0; i < S2MPS11_CLKS_NUM; i++)
 133                 of_property_read_string_index(clk_np, "clock-output-names", i,
 134                                 &clks_init[i].name);
 135
 136         return clk_np;
 137 }
 138
 139 static int s2mps11_clk_probe(struct platform_device *pdev)
 140 {
 141         struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
 142         struct s2mps11_clk *s2mps11_clks;
 143         struct clk_onecell_data *clk_data;
 144         unsigned int s2mps11_reg;
 145         int i, ret = 0;
 146         enum sec_device_type hwid = platform_get_device_id(pdev)->driver_data;
 147
 148         s2mps11_clks = devm_kcalloc(&pdev->dev, S2MPS11_CLKS_NUM,
 149                                 sizeof(*s2mps11_clks), GFP_KERNEL);
 150         if (!s2mps11_clks)
 151                 return -ENOMEM;
 152
 153         clk_data = devm_kzalloc(&pdev->dev, sizeof(*clk_data), GFP_KERNEL);
 154         if (!clk_data)
 155                 return -ENOMEM;
 156
 157         clk_data->clks = devm_kcalloc(&pdev->dev, S2MPS11_CLKS_NUM,
 158                                 sizeof(struct clk *), GFP_KERNEL);
 159         if (!clk_data->clks)
 160                 return -ENOMEM;
 161
 162         switch (hwid) {
 163         case S2MPS11X:
 164                 s2mps11_reg = S2MPS11_REG_RTC_CTRL;
 165                 break;
 166         case S2MPS13X:
 167                 s2mps11_reg = S2MPS13_REG_RTCCTRL;
 168                 break;
 169         case S2MPS14X:
 170                 s2mps11_reg = S2MPS14_REG_RTCCTRL;
 171                 break;
 172         case S5M8767X:
 173                 s2mps11_reg = S5M8767_REG_CTRL1;
 174                 break;
 175         default:
 176                 dev_err(&pdev->dev, "Invalid device type\n");
 177                 return -EINVAL;
 178         }
 179
 180         /* Store clocks of_node in first element of s2mps11_clks array */
 181         s2mps11_clks->clk_np = s2mps11_clk_parse_dt(pdev, s2mps11_clks_init);
 182         if (IS_ERR(s2mps11_clks->clk_np))
 183                 return PTR_ERR(s2mps11_clks->clk_np);
 184
 185         for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
 186                 if (i == S2MPS11_CLK_CP && hwid == S2MPS14X)
 187                         continue; /* Skip clocks not present in some devices */
 188                 s2mps11_clks[i].iodev = iodev;
 189                 s2mps11_clks[i].hw.init = &s2mps11_clks_init[i];
 190                 s2mps11_clks[i].mask = 1 << i;
 191                 s2mps11_clks[i].reg = s2mps11_reg;
 192
 193                 s2mps11_clks[i].clk = devm_clk_register(&pdev->dev,
 194                                                         &s2mps11_clks[i].hw);
 195                 if (IS_ERR(s2mps11_clks[i].clk)) {
 196                         dev_err(&pdev->dev, "Fail to register : %s\n",
 197                                                 s2mps11_clks_init[i].name);
 198                         ret = PTR_ERR(s2mps11_clks[i].clk);
 199                         goto err_reg;
 200                 }
 201
 202                 s2mps11_clks[i].lookup = clkdev_create(s2mps11_clks[i].clk,
 203                                         s2mps11_clks_init[i].name, NULL);
 204                 if (!s2mps11_clks[i].lookup) {
 205                         ret = -ENOMEM;
 206                         goto err_reg;
 207                 }
 208                 clk_data->clks[i] = s2mps11_clks[i].clk;
 209         }
 210
 211         clk_data->clk_num = S2MPS11_CLKS_NUM;
 212         of_clk_add_provider(s2mps11_clks->clk_np, of_clk_src_onecell_get,
 213                         clk_data);
 214
 215         platform_set_drvdata(pdev, s2mps11_clks);
 216
 217         return ret;
 218
 219 err_reg:
 220         while (--i >= 0)
 221                 clkdev_drop(s2mps11_clks[i].lookup);
 222
 223         return ret;
 224 }
 225
 226 static int s2mps11_clk_remove(struct platform_device *pdev)
 227 {
 228         struct s2mps11_clk *s2mps11_clks = platform_get_drvdata(pdev);
 229         int i;
 230
 231         of_clk_del_provider(s2mps11_clks[0].clk_np);
 232         /* Drop the reference obtained in s2mps11_clk_parse_dt */
 233         of_node_put(s2mps11_clks[0].clk_np);
 234
 235         for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
 236                 /* Skip clocks not present on S2MPS14 */
 237                 if (!s2mps11_clks[i].lookup)
 238                         continue;
 239                 clkdev_drop(s2mps11_clks[i].lookup);
 240         }
 241
 242         return 0;
 243 }
 244
 245 static const struct platform_device_id s2mps11_clk_id[] = {
 246         { "s2mps11-clk", S2MPS11X},
 247         { "s2mps13-clk", S2MPS13X},
 248         { "s2mps14-clk", S2MPS14X},
 249         { "s5m8767-clk", S5M8767X},
 250         { },
 251 };
 252 MODULE_DEVICE_TABLE(platform, s2mps11_clk_id);
 253
 254 static struct platform_driver s2mps11_clk_driver = {
 255         .driver = {
 256                 .name  = "s2mps11-clk",
 257         },
 258         .probe = s2mps11_clk_probe,
 259         .remove = s2mps11_clk_remove,
 260         .id_table = s2mps11_clk_id,
 261 };
 262
 263 static int __init s2mps11_clk_init(void)
 264 {
 265         return platform_driver_register(&s2mps11_clk_driver);
 266 }
 267 subsys_initcall(s2mps11_clk_init);
 268
 269 static void __exit s2mps11_clk_cleanup(void)
 270 {
 271         platform_driver_unregister(&s2mps11_clk_driver);
 272 }
 273 module_exit(s2mps11_clk_cleanup);
 274
 275 MODULE_DESCRIPTION("S2MPS11 Clock Driver");
 276 MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>");
 277 MODULE_LICENSE("GPL");