drivers/clk/mediatek/clk-gate.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2014 MediaTek Inc.
   4  * Author: James Liao <jamesjj.liao@mediatek.com>
   5  */
   6
   7 #include <linux/clk-provider.h>
   8 #include <linux/mfd/syscon.h>
   9 #include <linux/module.h>
  10 #include <linux/printk.h>
  11 #include <linux/regmap.h>
  12 #include <linux/slab.h>
  13 #include <linux/types.h>
  14
  15 #include "clk-gate.h"
  16
  17 struct mtk_clk_gate {
  18         struct clk_hw   hw;
  19         struct regmap   *regmap;
  20         int             set_ofs;
  21         int             clr_ofs;
  22         int             sta_ofs;
  23         u8              bit;
  24 };
  25
  26 static inline struct mtk_clk_gate *to_mtk_clk_gate(struct clk_hw *hw)
  27 {
  28         return container_of(hw, struct mtk_clk_gate, hw);
  29 }
  30
  31 static u32 mtk_get_clockgating(struct clk_hw *hw)
  32 {
  33         struct mtk_clk_gate *cg = to_mtk_clk_gate(hw);
  34         u32 val;
  35
  36         regmap_read(cg->regmap, cg->sta_ofs, &val);
  37
  38         return val & BIT(cg->bit);
  39 }
  40
  41 static int mtk_cg_bit_is_cleared(struct clk_hw *hw)
  42 {
  43         return mtk_get_clockgating(hw) == 0;
  44 }
  45
  46 static int mtk_cg_bit_is_set(struct clk_hw *hw)
  47 {
  48         return mtk_get_clockgating(hw) != 0;
  49 }
  50
  51 static void mtk_cg_set_bit(struct clk_hw *hw)
  52 {
  53         struct mtk_clk_gate *cg = to_mtk_clk_gate(hw);
  54
  55         regmap_write(cg->regmap, cg->set_ofs, BIT(cg->bit));
  56 }
  57
  58 static void mtk_cg_clr_bit(struct clk_hw *hw)
  59 {
  60         struct mtk_clk_gate *cg = to_mtk_clk_gate(hw);
  61
  62         regmap_write(cg->regmap, cg->clr_ofs, BIT(cg->bit));
  63 }
  64
  65 static void mtk_cg_set_bit_no_setclr(struct clk_hw *hw)
  66 {
  67         struct mtk_clk_gate *cg = to_mtk_clk_gate(hw);
  68
  69         regmap_set_bits(cg->regmap, cg->sta_ofs, BIT(cg->bit));
  70 }
  71
  72 static void mtk_cg_clr_bit_no_setclr(struct clk_hw *hw)
  73 {
  74         struct mtk_clk_gate *cg = to_mtk_clk_gate(hw);
  75
  76         regmap_clear_bits(cg->regmap, cg->sta_ofs, BIT(cg->bit));
  77 }
  78
  79 static int mtk_cg_enable(struct clk_hw *hw)
  80 {
  81         mtk_cg_clr_bit(hw);
  82
  83         return 0;
  84 }
  85
  86 static void mtk_cg_disable(struct clk_hw *hw)
  87 {
  88         mtk_cg_set_bit(hw);
  89 }
  90
  91 static int mtk_cg_enable_inv(struct clk_hw *hw)
  92 {
  93         mtk_cg_set_bit(hw);
  94
  95         return 0;
  96 }
  97
  98 static void mtk_cg_disable_inv(struct clk_hw *hw)
  99 {
 100         mtk_cg_clr_bit(hw);
 101 }
 102
 103 static int mtk_cg_enable_no_setclr(struct clk_hw *hw)
 104 {
 105         mtk_cg_clr_bit_no_setclr(hw);
 106
 107         return 0;
 108 }
 109
 110 static void mtk_cg_disable_no_setclr(struct clk_hw *hw)
 111 {
 112         mtk_cg_set_bit_no_setclr(hw);
 113 }
 114
 115 static int mtk_cg_enable_inv_no_setclr(struct clk_hw *hw)
 116 {
 117         mtk_cg_set_bit_no_setclr(hw);
 118
 119         return 0;
 120 }
 121
 122 static void mtk_cg_disable_inv_no_setclr(struct clk_hw *hw)
 123 {
 124         mtk_cg_clr_bit_no_setclr(hw);
 125 }
 126
 127 const struct clk_ops mtk_clk_gate_ops_setclr = {
 128         .is_enabled     = mtk_cg_bit_is_cleared,
 129         .enable         = mtk_cg_enable,
 130         .disable        = mtk_cg_disable,
 131 };
 132 EXPORT_SYMBOL_GPL(mtk_clk_gate_ops_setclr);
 133
 134 const struct clk_ops mtk_clk_gate_ops_setclr_inv = {
 135         .is_enabled     = mtk_cg_bit_is_set,
 136         .enable         = mtk_cg_enable_inv,
 137         .disable        = mtk_cg_disable_inv,
 138 };
 139 EXPORT_SYMBOL_GPL(mtk_clk_gate_ops_setclr_inv);
 140
 141 const struct clk_ops mtk_clk_gate_ops_no_setclr = {
 142         .is_enabled     = mtk_cg_bit_is_cleared,
 143         .enable         = mtk_cg_enable_no_setclr,
 144         .disable        = mtk_cg_disable_no_setclr,
 145 };
 146 EXPORT_SYMBOL_GPL(mtk_clk_gate_ops_no_setclr);
 147
 148 const struct clk_ops mtk_clk_gate_ops_no_setclr_inv = {
 149         .is_enabled     = mtk_cg_bit_is_set,
 150         .enable         = mtk_cg_enable_inv_no_setclr,
 151         .disable        = mtk_cg_disable_inv_no_setclr,
 152 };
 153 EXPORT_SYMBOL_GPL(mtk_clk_gate_ops_no_setclr_inv);
 154
 155 static struct clk_hw *mtk_clk_register_gate(struct device *dev, const char *name,
 156                                          const char *parent_name,
 157                                          struct regmap *regmap, int set_ofs,
 158                                          int clr_ofs, int sta_ofs, u8 bit,
 159                                          const struct clk_ops *ops,
 160                                          unsigned long flags)
 161 {
 162         struct mtk_clk_gate *cg;
 163         int ret;
 164         struct clk_init_data init = {};
 165
 166         cg = kzalloc(sizeof(*cg), GFP_KERNEL);
 167         if (!cg)
 168                 return ERR_PTR(-ENOMEM);
 169
 170         init.name = name;
 171         init.flags = flags | CLK_SET_RATE_PARENT;
 172         init.parent_names = parent_name ? &parent_name : NULL;
 173         init.num_parents = parent_name ? 1 : 0;
 174         init.ops = ops;
 175
 176         cg->regmap = regmap;
 177         cg->set_ofs = set_ofs;
 178         cg->clr_ofs = clr_ofs;
 179         cg->sta_ofs = sta_ofs;
 180         cg->bit = bit;
 181
 182         cg->hw.init = &init;
 183
 184         ret = clk_hw_register(dev, &cg->hw);
 185         if (ret) {
 186                 kfree(cg);
 187                 return ERR_PTR(ret);
 188         }
 189
 190         return &cg->hw;
 191 }
 192
 193 static void mtk_clk_unregister_gate(struct clk_hw *hw)
 194 {
 195         struct mtk_clk_gate *cg;
 196         if (!hw)
 197                 return;
 198
 199         cg = to_mtk_clk_gate(hw);
 200
 201         clk_hw_unregister(hw);
 202         kfree(cg);
 203 }
 204
 205 int mtk_clk_register_gates(struct device *dev, struct device_node *node,
 206                            const struct mtk_gate *clks, int num,
 207                            struct clk_hw_onecell_data *clk_data)
 208 {
 209         int i;
 210         struct clk_hw *hw;
 211         struct regmap *regmap;
 212
 213         if (!clk_data)
 214                 return -ENOMEM;
 215
 216         regmap = device_node_to_regmap(node);
 217         if (IS_ERR(regmap)) {
 218                 pr_err("Cannot find regmap for %pOF: %pe\n", node, regmap);
 219                 return PTR_ERR(regmap);
 220         }
 221
 222         for (i = 0; i < num; i++) {
 223                 const struct mtk_gate *gate = &clks[i];
 224
 225                 if (!IS_ERR_OR_NULL(clk_data->hws[gate->id])) {
 226                         pr_warn("%pOF: Trying to register duplicate clock ID: %d\n",
 227                                 node, gate->id);
 228                         continue;
 229                 }
 230
 231                 hw = mtk_clk_register_gate(dev, gate->name, gate->parent_name,
 232                                             regmap,
 233                                             gate->regs->set_ofs,
 234                                             gate->regs->clr_ofs,
 235                                             gate->regs->sta_ofs,
 236                                             gate->shift, gate->ops,
 237                                             gate->flags);
 238
 239                 if (IS_ERR(hw)) {
 240                         pr_err("Failed to register clk %s: %pe\n", gate->name,
 241                                hw);
 242                         goto err;
 243                 }
 244
 245                 clk_data->hws[gate->id] = hw;
 246         }
 247
 248         return 0;
 249
 250 err:
 251         while (--i >= 0) {
 252                 const struct mtk_gate *gate = &clks[i];
 253
 254                 if (IS_ERR_OR_NULL(clk_data->hws[gate->id]))
 255                         continue;
 256
 257                 mtk_clk_unregister_gate(clk_data->hws[gate->id]);
 258                 clk_data->hws[gate->id] = ERR_PTR(-ENOENT);
 259         }
 260
 261         return PTR_ERR(hw);
 262 }
 263 EXPORT_SYMBOL_GPL(mtk_clk_register_gates);
 264
 265 void mtk_clk_unregister_gates(const struct mtk_gate *clks, int num,
 266                               struct clk_hw_onecell_data *clk_data)
 267 {
 268         int i;
 269
 270         if (!clk_data)
 271                 return;
 272
 273         for (i = num; i > 0; i--) {
 274                 const struct mtk_gate *gate = &clks[i - 1];
 275
 276                 if (IS_ERR_OR_NULL(clk_data->hws[gate->id]))
 277                         continue;
 278
 279                 mtk_clk_unregister_gate(clk_data->hws[gate->id]);
 280                 clk_data->hws[gate->id] = ERR_PTR(-ENOENT);
 281         }
 282 }
 283 EXPORT_SYMBOL_GPL(mtk_clk_unregister_gates);
 284
 285 MODULE_LICENSE("GPL");