1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Lochnagar clock control
4  *
5  * Copyright (c) 2017-2018 Cirrus Logic, Inc. and
6  *                         Cirrus Logic International Semiconductor Ltd.
7  *
8  * Author: Charles Keepax <ckeepax@opensource.cirrus.com>
9  */
10 
11 #include <linux/clk-provider.h>
12 #include <linux/device.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/platform_device.h>
16 #include <linux/property.h>
17 #include <linux/regmap.h>
18 
19 #include <linux/mfd/lochnagar1_regs.h>
20 #include <linux/mfd/lochnagar2_regs.h>
21 
22 #include <dt-bindings/clock/lochnagar.h>
23 
24 #define LOCHNAGAR_NUM_CLOCKS	(LOCHNAGAR_SPDIF_CLKOUT + 1)
25 
26 struct lochnagar_clk {
27 	const char * const name;
28 	struct clk_hw hw;
29 
30 	struct lochnagar_clk_priv *priv;
31 
32 	u16 cfg_reg;
33 	u16 ena_mask;
34 
35 	u16 src_reg;
36 	u16 src_mask;
37 };
38 
39 struct lochnagar_clk_priv {
40 	struct device *dev;
41 	struct regmap *regmap;
42 
43 	struct lochnagar_clk lclks[LOCHNAGAR_NUM_CLOCKS];
44 };
45 
46 #define LN_PARENT(NAME) { .name = NAME, .fw_name = NAME }
47 
48 static const struct clk_parent_data lochnagar1_clk_parents[] = {
49 	LN_PARENT("ln-none"),
50 	LN_PARENT("ln-spdif-mclk"),
51 	LN_PARENT("ln-psia1-mclk"),
52 	LN_PARENT("ln-psia2-mclk"),
53 	LN_PARENT("ln-cdc-clkout"),
54 	LN_PARENT("ln-dsp-clkout"),
55 	LN_PARENT("ln-pmic-32k"),
56 	LN_PARENT("ln-gf-mclk1"),
57 	LN_PARENT("ln-gf-mclk3"),
58 	LN_PARENT("ln-gf-mclk2"),
59 	LN_PARENT("ln-gf-mclk4"),
60 };
61 
62 static const struct clk_parent_data lochnagar2_clk_parents[] = {
63 	LN_PARENT("ln-none"),
64 	LN_PARENT("ln-cdc-clkout"),
65 	LN_PARENT("ln-dsp-clkout"),
66 	LN_PARENT("ln-pmic-32k"),
67 	LN_PARENT("ln-spdif-mclk"),
68 	LN_PARENT("ln-clk-12m"),
69 	LN_PARENT("ln-clk-11m"),
70 	LN_PARENT("ln-clk-24m"),
71 	LN_PARENT("ln-clk-22m"),
72 	LN_PARENT("ln-clk-8m"),
73 	LN_PARENT("ln-usb-clk-24m"),
74 	LN_PARENT("ln-gf-mclk1"),
75 	LN_PARENT("ln-gf-mclk3"),
76 	LN_PARENT("ln-gf-mclk2"),
77 	LN_PARENT("ln-psia1-mclk"),
78 	LN_PARENT("ln-psia2-mclk"),
79 	LN_PARENT("ln-spdif-clkout"),
80 	LN_PARENT("ln-adat-mclk"),
81 	LN_PARENT("ln-usb-clk-12m"),
82 };
83 
84 #define LN1_CLK(ID, NAME, REG) \
85 	[LOCHNAGAR_##ID] = { \
86 		.name = NAME, \
87 		.cfg_reg = LOCHNAGAR1_##REG, \
88 		.ena_mask = LOCHNAGAR1_##ID##_ENA_MASK, \
89 		.src_reg = LOCHNAGAR1_##ID##_SEL, \
90 		.src_mask = LOCHNAGAR1_SRC_MASK, \
91 	}
92 
93 #define LN2_CLK(ID, NAME) \
94 	[LOCHNAGAR_##ID] = { \
95 		.name = NAME, \
96 		.cfg_reg = LOCHNAGAR2_##ID##_CTRL, \
97 		.src_reg = LOCHNAGAR2_##ID##_CTRL, \
98 		.ena_mask = LOCHNAGAR2_CLK_ENA_MASK, \
99 		.src_mask = LOCHNAGAR2_CLK_SRC_MASK, \
100 	}
101 
102 static const struct lochnagar_clk lochnagar1_clks[LOCHNAGAR_NUM_CLOCKS] = {
103 	LN1_CLK(CDC_MCLK1,      "ln-cdc-mclk1",  CDC_AIF_CTRL2),
104 	LN1_CLK(CDC_MCLK2,      "ln-cdc-mclk2",  CDC_AIF_CTRL2),
105 	LN1_CLK(DSP_CLKIN,      "ln-dsp-clkin",  DSP_AIF),
106 	LN1_CLK(GF_CLKOUT1,     "ln-gf-clkout1", GF_AIF1),
107 };
108 
109 static const struct lochnagar_clk lochnagar2_clks[LOCHNAGAR_NUM_CLOCKS] = {
110 	LN2_CLK(CDC_MCLK1,      "ln-cdc-mclk1"),
111 	LN2_CLK(CDC_MCLK2,      "ln-cdc-mclk2"),
112 	LN2_CLK(DSP_CLKIN,      "ln-dsp-clkin"),
113 	LN2_CLK(GF_CLKOUT1,     "ln-gf-clkout1"),
114 	LN2_CLK(GF_CLKOUT2,     "ln-gf-clkout2"),
115 	LN2_CLK(PSIA1_MCLK,     "ln-psia1-mclk"),
116 	LN2_CLK(PSIA2_MCLK,     "ln-psia2-mclk"),
117 	LN2_CLK(SPDIF_MCLK,     "ln-spdif-mclk"),
118 	LN2_CLK(ADAT_MCLK,      "ln-adat-mclk"),
119 	LN2_CLK(SOUNDCARD_MCLK, "ln-soundcard-mclk"),
120 };
121 
122 struct lochnagar_config {
123 	const struct clk_parent_data *parents;
124 	int nparents;
125 	const struct lochnagar_clk *clks;
126 };
127 
128 static const struct lochnagar_config lochnagar1_conf = {
129 	.parents = lochnagar1_clk_parents,
130 	.nparents = ARRAY_SIZE(lochnagar1_clk_parents),
131 	.clks = lochnagar1_clks,
132 };
133 
134 static const struct lochnagar_config lochnagar2_conf = {
135 	.parents = lochnagar2_clk_parents,
136 	.nparents = ARRAY_SIZE(lochnagar2_clk_parents),
137 	.clks = lochnagar2_clks,
138 };
139 
lochnagar_hw_to_lclk(struct clk_hw * hw)140 static inline struct lochnagar_clk *lochnagar_hw_to_lclk(struct clk_hw *hw)
141 {
142 	return container_of(hw, struct lochnagar_clk, hw);
143 }
144 
lochnagar_clk_prepare(struct clk_hw * hw)145 static int lochnagar_clk_prepare(struct clk_hw *hw)
146 {
147 	struct lochnagar_clk *lclk = lochnagar_hw_to_lclk(hw);
148 	struct lochnagar_clk_priv *priv = lclk->priv;
149 	struct regmap *regmap = priv->regmap;
150 	int ret;
151 
152 	ret = regmap_update_bits(regmap, lclk->cfg_reg,
153 				 lclk->ena_mask, lclk->ena_mask);
154 	if (ret < 0)
155 		dev_dbg(priv->dev, "Failed to prepare %s: %d\n",
156 			lclk->name, ret);
157 
158 	return ret;
159 }
160 
lochnagar_clk_unprepare(struct clk_hw * hw)161 static void lochnagar_clk_unprepare(struct clk_hw *hw)
162 {
163 	struct lochnagar_clk *lclk = lochnagar_hw_to_lclk(hw);
164 	struct lochnagar_clk_priv *priv = lclk->priv;
165 	struct regmap *regmap = priv->regmap;
166 	int ret;
167 
168 	ret = regmap_update_bits(regmap, lclk->cfg_reg, lclk->ena_mask, 0);
169 	if (ret < 0)
170 		dev_dbg(priv->dev, "Failed to unprepare %s: %d\n",
171 			lclk->name, ret);
172 }
173 
lochnagar_clk_set_parent(struct clk_hw * hw,u8 index)174 static int lochnagar_clk_set_parent(struct clk_hw *hw, u8 index)
175 {
176 	struct lochnagar_clk *lclk = lochnagar_hw_to_lclk(hw);
177 	struct lochnagar_clk_priv *priv = lclk->priv;
178 	struct regmap *regmap = priv->regmap;
179 	int ret;
180 
181 	ret = regmap_update_bits(regmap, lclk->src_reg, lclk->src_mask, index);
182 	if (ret < 0)
183 		dev_dbg(priv->dev, "Failed to reparent %s: %d\n",
184 			lclk->name, ret);
185 
186 	return ret;
187 }
188 
lochnagar_clk_get_parent(struct clk_hw * hw)189 static u8 lochnagar_clk_get_parent(struct clk_hw *hw)
190 {
191 	struct lochnagar_clk *lclk = lochnagar_hw_to_lclk(hw);
192 	struct lochnagar_clk_priv *priv = lclk->priv;
193 	struct regmap *regmap = priv->regmap;
194 	unsigned int val;
195 	int ret;
196 
197 	ret = regmap_read(regmap, lclk->src_reg, &val);
198 	if (ret < 0) {
199 		dev_dbg(priv->dev, "Failed to read parent of %s: %d\n",
200 			lclk->name, ret);
201 		return clk_hw_get_num_parents(hw);
202 	}
203 
204 	val &= lclk->src_mask;
205 
206 	return val;
207 }
208 
209 static const struct clk_ops lochnagar_clk_ops = {
210 	.prepare = lochnagar_clk_prepare,
211 	.unprepare = lochnagar_clk_unprepare,
212 	.determine_rate = clk_hw_determine_rate_no_reparent,
213 	.set_parent = lochnagar_clk_set_parent,
214 	.get_parent = lochnagar_clk_get_parent,
215 };
216 
217 static struct clk_hw *
lochnagar_of_clk_hw_get(struct of_phandle_args * clkspec,void * data)218 lochnagar_of_clk_hw_get(struct of_phandle_args *clkspec, void *data)
219 {
220 	struct lochnagar_clk_priv *priv = data;
221 	unsigned int idx = clkspec->args[0];
222 
223 	if (idx >= ARRAY_SIZE(priv->lclks)) {
224 		dev_err(priv->dev, "Invalid index %u\n", idx);
225 		return ERR_PTR(-EINVAL);
226 	}
227 
228 	return &priv->lclks[idx].hw;
229 }
230 
231 static const struct of_device_id lochnagar_of_match[] = {
232 	{ .compatible = "cirrus,lochnagar1-clk", .data = &lochnagar1_conf },
233 	{ .compatible = "cirrus,lochnagar2-clk", .data = &lochnagar2_conf },
234 	{}
235 };
236 MODULE_DEVICE_TABLE(of, lochnagar_of_match);
237 
lochnagar_clk_probe(struct platform_device * pdev)238 static int lochnagar_clk_probe(struct platform_device *pdev)
239 {
240 	struct clk_init_data clk_init = {
241 		.ops = &lochnagar_clk_ops,
242 	};
243 	struct device *dev = &pdev->dev;
244 	struct lochnagar_clk_priv *priv;
245 	struct lochnagar_clk *lclk;
246 	struct lochnagar_config *conf;
247 	int ret, i;
248 
249 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
250 	if (!priv)
251 		return -ENOMEM;
252 
253 	priv->dev = dev;
254 	priv->regmap = dev_get_regmap(dev->parent, NULL);
255 	conf = (struct lochnagar_config *)device_get_match_data(dev);
256 
257 	memcpy(priv->lclks, conf->clks, sizeof(priv->lclks));
258 
259 	clk_init.parent_data = conf->parents;
260 	clk_init.num_parents = conf->nparents;
261 
262 	for (i = 0; i < ARRAY_SIZE(priv->lclks); i++) {
263 		lclk = &priv->lclks[i];
264 
265 		if (!lclk->name)
266 			continue;
267 
268 		clk_init.name = lclk->name;
269 
270 		lclk->priv = priv;
271 		lclk->hw.init = &clk_init;
272 
273 		ret = devm_clk_hw_register(dev, &lclk->hw);
274 		if (ret) {
275 			dev_err(dev, "Failed to register %s: %d\n",
276 				lclk->name, ret);
277 			return ret;
278 		}
279 	}
280 
281 	ret = devm_of_clk_add_hw_provider(dev, lochnagar_of_clk_hw_get, priv);
282 	if (ret < 0)
283 		dev_err(dev, "Failed to register provider: %d\n", ret);
284 
285 	return ret;
286 }
287 
288 static struct platform_driver lochnagar_clk_driver = {
289 	.driver = {
290 		.name = "lochnagar-clk",
291 		.of_match_table = lochnagar_of_match,
292 	},
293 	.probe = lochnagar_clk_probe,
294 };
295 module_platform_driver(lochnagar_clk_driver);
296 
297 MODULE_AUTHOR("Charles Keepax <ckeepax@opensource.cirrus.com>");
298 MODULE_DESCRIPTION("Clock driver for Cirrus Logic Lochnagar Board");
299 MODULE_LICENSE("GPL v2");
300