drivers/clk/keystone/syscon-clk.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2020 Texas Instruments Incorporated - https://www.ti.com/
   4  */
   5
   6 #include <linux/clk-provider.h>
   7 #include <linux/kernel.h>
   8 #include <linux/mfd/syscon.h>
   9 #include <linux/module.h>
  10 #include <linux/platform_device.h>
  11 #include <linux/regmap.h>
  12 #include <linux/slab.h>
  13
  14 struct ti_syscon_gate_clk_priv {
  15         struct clk_hw hw;
  16         struct regmap *regmap;
  17         u32 reg;
  18         u32 idx;
  19 };
  20
  21 struct ti_syscon_gate_clk_data {
  22         char *name;
  23         u32 offset;
  24         u32 bit_idx;
  25 };
  26
  27 static struct
  28 ti_syscon_gate_clk_priv *to_ti_syscon_gate_clk_priv(struct clk_hw *hw)
  29 {
  30         return container_of(hw, struct ti_syscon_gate_clk_priv, hw);
  31 }
  32
  33 static int ti_syscon_gate_clk_enable(struct clk_hw *hw)
  34 {
  35         struct ti_syscon_gate_clk_priv *priv = to_ti_syscon_gate_clk_priv(hw);
  36
  37         return regmap_write_bits(priv->regmap, priv->reg, priv->idx,
  38                                  priv->idx);
  39 }
  40
  41 static void ti_syscon_gate_clk_disable(struct clk_hw *hw)
  42 {
  43         struct ti_syscon_gate_clk_priv *priv = to_ti_syscon_gate_clk_priv(hw);
  44
  45         regmap_write_bits(priv->regmap, priv->reg, priv->idx, 0);
  46 }
  47
  48 static int ti_syscon_gate_clk_is_enabled(struct clk_hw *hw)
  49 {
  50         unsigned int val;
  51         struct ti_syscon_gate_clk_priv *priv = to_ti_syscon_gate_clk_priv(hw);
  52
  53         regmap_read(priv->regmap, priv->reg, &val);
  54
  55         return !!(val & priv->idx);
  56 }
  57
  58 static const struct clk_ops ti_syscon_gate_clk_ops = {
  59         .enable         = ti_syscon_gate_clk_enable,
  60         .disable        = ti_syscon_gate_clk_disable,
  61         .is_enabled     = ti_syscon_gate_clk_is_enabled,
  62 };
  63
  64 static struct clk_hw
  65 *ti_syscon_gate_clk_register(struct device *dev, struct regmap *regmap,
  66                              const char *parent_name,
  67                              const struct ti_syscon_gate_clk_data *data)
  68 {
  69         struct ti_syscon_gate_clk_priv *priv;
  70         struct clk_init_data init;
  71         char *name = NULL;
  72         int ret;
  73
  74         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
  75         if (!priv)
  76                 return ERR_PTR(-ENOMEM);
  77
  78         init.ops = &ti_syscon_gate_clk_ops;
  79         if (parent_name) {
  80                 name = kasprintf(GFP_KERNEL, "%s:%s", data->name, parent_name);
  81                 init.name = name;
  82                 init.parent_names = &parent_name;
  83                 init.num_parents = 1;
  84                 init.flags = CLK_SET_RATE_PARENT;
  85         } else {
  86                 init.name = data->name;
  87                 init.parent_names = NULL;
  88                 init.num_parents = 0;
  89                 init.flags = 0;
  90         }
  91
  92         priv->regmap = regmap;
  93         priv->reg = data->offset;
  94         priv->idx = BIT(data->bit_idx);
  95         priv->hw.init = &init;
  96
  97         ret = devm_clk_hw_register(dev, &priv->hw);
  98
  99         if (name)
 100                 kfree(init.name);
 101
 102         if (ret)
 103                 return ERR_PTR(ret);
 104
 105         return &priv->hw;
 106 }
 107
 108 static int ti_syscon_gate_clk_probe(struct platform_device *pdev)
 109 {
 110         const struct ti_syscon_gate_clk_data *data, *p;
 111         struct clk_hw_onecell_data *hw_data;
 112         struct device *dev = &pdev->dev;
 113         int num_clks, num_parents, i;
 114         const char *parent_name;
 115         struct regmap *regmap;
 116
 117         data = device_get_match_data(dev);
 118         if (!data)
 119                 return -EINVAL;
 120
 121         regmap = device_node_to_regmap(dev->of_node);
 122         if (IS_ERR(regmap))
 123                 return dev_err_probe(dev, PTR_ERR(regmap),
 124                                      "failed to get regmap\n");
 125
 126         num_clks = 0;
 127         for (p = data; p->name; p++)
 128                 num_clks++;
 129
 130         num_parents = of_clk_get_parent_count(dev->of_node);
 131         if (of_device_is_compatible(dev->of_node, "ti,am62-audio-refclk") &&
 132             num_parents == 0) {
 133                 return dev_err_probe(dev, -EINVAL,
 134                                      "must specify a parent clock\n");
 135         }
 136
 137         hw_data = devm_kzalloc(dev, struct_size(hw_data, hws, num_clks),
 138                                GFP_KERNEL);
 139         if (!hw_data)
 140                 return -ENOMEM;
 141
 142         hw_data->num = num_clks;
 143
 144         parent_name = of_clk_get_parent_name(dev->of_node, 0);
 145         for (i = 0; i < num_clks; i++) {
 146                 hw_data->hws[i] = ti_syscon_gate_clk_register(dev, regmap,
 147                                                               parent_name,
 148                                                               &data[i]);
 149                 if (IS_ERR(hw_data->hws[i]))
 150                         dev_warn(dev, "failed to register %s\n",
 151                                  data[i].name);
 152         }
 153
 154         if (num_clks == 1)
 155                 return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
 156                                                    hw_data->hws[0]);
 157         return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, hw_data);
 158 }
 159
 160 #define TI_SYSCON_CLK_GATE(_name, _offset, _bit_idx)    \
 161         {                                               \
 162                 .name = _name,                          \
 163                 .offset = (_offset),                    \
 164                 .bit_idx = (_bit_idx),                  \
 165         }
 166
 167 static const struct ti_syscon_gate_clk_data am654_clk_data[] = {
 168         TI_SYSCON_CLK_GATE("ehrpwm_tbclk0", 0x0, 0),
 169         TI_SYSCON_CLK_GATE("ehrpwm_tbclk1", 0x4, 0),
 170         TI_SYSCON_CLK_GATE("ehrpwm_tbclk2", 0x8, 0),
 171         TI_SYSCON_CLK_GATE("ehrpwm_tbclk3", 0xc, 0),
 172         TI_SYSCON_CLK_GATE("ehrpwm_tbclk4", 0x10, 0),
 173         TI_SYSCON_CLK_GATE("ehrpwm_tbclk5", 0x14, 0),
 174         { /* Sentinel */ },
 175 };
 176
 177 static const struct ti_syscon_gate_clk_data am64_clk_data[] = {
 178         TI_SYSCON_CLK_GATE("epwm_tbclk0", 0x0, 0),
 179         TI_SYSCON_CLK_GATE("epwm_tbclk1", 0x0, 1),
 180         TI_SYSCON_CLK_GATE("epwm_tbclk2", 0x0, 2),
 181         TI_SYSCON_CLK_GATE("epwm_tbclk3", 0x0, 3),
 182         TI_SYSCON_CLK_GATE("epwm_tbclk4", 0x0, 4),
 183         TI_SYSCON_CLK_GATE("epwm_tbclk5", 0x0, 5),
 184         TI_SYSCON_CLK_GATE("epwm_tbclk6", 0x0, 6),
 185         TI_SYSCON_CLK_GATE("epwm_tbclk7", 0x0, 7),
 186         TI_SYSCON_CLK_GATE("epwm_tbclk8", 0x0, 8),
 187         { /* Sentinel */ },
 188 };
 189
 190 static const struct ti_syscon_gate_clk_data am62_clk_data[] = {
 191         TI_SYSCON_CLK_GATE("epwm_tbclk0", 0x0, 0),
 192         TI_SYSCON_CLK_GATE("epwm_tbclk1", 0x0, 1),
 193         TI_SYSCON_CLK_GATE("epwm_tbclk2", 0x0, 2),
 194         { /* Sentinel */ },
 195 };
 196
 197 static const struct ti_syscon_gate_clk_data am62_audio_clk_data[] = {
 198         TI_SYSCON_CLK_GATE("audio_refclk", 0x0, 15),
 199         { /* Sentinel */ },
 200 };
 201
 202 static const struct of_device_id ti_syscon_gate_clk_ids[] = {
 203         {
 204                 .compatible = "ti,am654-ehrpwm-tbclk",
 205                 .data = &am654_clk_data,
 206         },
 207         {
 208                 .compatible = "ti,am64-epwm-tbclk",
 209                 .data = &am64_clk_data,
 210         },
 211         {
 212                 .compatible = "ti,am62-epwm-tbclk",
 213                 .data = &am62_clk_data,
 214         },
 215         {
 216                 .compatible = "ti,am62-audio-refclk",
 217                 .data = &am62_audio_clk_data,
 218         },
 219         { }
 220 };
 221 MODULE_DEVICE_TABLE(of, ti_syscon_gate_clk_ids);
 222
 223 static struct platform_driver ti_syscon_gate_clk_driver = {
 224         .probe = ti_syscon_gate_clk_probe,
 225         .driver = {
 226                 .name = "ti-syscon-gate-clk",
 227                 .of_match_table = ti_syscon_gate_clk_ids,
 228         },
 229 };
 230 module_platform_driver(ti_syscon_gate_clk_driver);
 231
 232 MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>");
 233 MODULE_DESCRIPTION("Syscon backed gate-clock driver");
 234 MODULE_LICENSE("GPL");