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
to_ti_syscon_gate_clk_priv(struct clk_hw * hw)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
ti_syscon_gate_clk_enable(struct clk_hw * hw)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
ti_syscon_gate_clk_disable(struct clk_hw * hw)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
ti_syscon_gate_clk_is_enabled(struct clk_hw * hw)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
ti_syscon_gate_clk_register(struct device * dev,struct regmap * regmap,const char * parent_name,const struct ti_syscon_gate_clk_data * data)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
ti_syscon_gate_clk_probe(struct platform_device * pdev)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");
235