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
 14struct ti_syscon_gate_clk_priv {
 15	struct clk_hw hw;
 16	struct regmap *regmap;
 17	u32 reg;
 18	u32 idx;
 19};
 20
 21struct ti_syscon_gate_clk_data {
 22	char *name;
 23	u32 offset;
 24	u32 bit_idx;
 25};
 26
 27static struct
 28ti_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
 33static 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
 41static 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
 48static 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
 58static 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
 64static 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
108static 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
167static 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
177static 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
190static 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
197static const struct ti_syscon_gate_clk_data am62_audio_clk_data[] = {
198	TI_SYSCON_CLK_GATE("audio_refclk", 0x0, 15),
199	{ /* Sentinel */ },
200};
201
202static 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};
221MODULE_DEVICE_TABLE(of, ti_syscon_gate_clk_ids);
222
223static 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};
230module_platform_driver(ti_syscon_gate_clk_driver);
231
232MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>");
233MODULE_DESCRIPTION("Syscon backed gate-clock driver");
234MODULE_LICENSE("GPL");