xref: /linux/drivers/clk/samsung/clk-exynos-audss.c (revision 0c436dfe5c25d0931b164b944165259f95e5281f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2013 Samsung Electronics Co., Ltd.
4  * Author: Padmavathi Venna <padma.v@samsung.com>
5  *
6  * Common Clock Framework support for Audio Subsystem Clock Controller.
7 */
8 
9 #include <linux/slab.h>
10 #include <linux/io.h>
11 #include <linux/clk.h>
12 #include <linux/clk-provider.h>
13 #include <linux/of.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 
18 #include <dt-bindings/clock/exynos-audss-clk.h>
19 
20 static DEFINE_SPINLOCK(lock);
21 static void __iomem *reg_base;
22 static struct clk_hw_onecell_data *clk_data;
23 /*
24  * On Exynos5420 this will be a clock which has to be enabled before any
25  * access to audss registers. Typically a child of EPLL.
26  *
27  * On other platforms this will be -ENODEV.
28  */
29 static struct clk *epll;
30 
31 #define ASS_CLK_SRC 0x0
32 #define ASS_CLK_DIV 0x4
33 #define ASS_CLK_GATE 0x8
34 
35 static unsigned long reg_save[][2] = {
36 	{ ASS_CLK_SRC,  0 },
37 	{ ASS_CLK_DIV,  0 },
38 	{ ASS_CLK_GATE, 0 },
39 };
40 
41 static int __maybe_unused exynos_audss_clk_suspend(struct device *dev)
42 {
43 	int i;
44 
45 	for (i = 0; i < ARRAY_SIZE(reg_save); i++)
46 		reg_save[i][1] = readl(reg_base + reg_save[i][0]);
47 
48 	return 0;
49 }
50 
51 static int __maybe_unused exynos_audss_clk_resume(struct device *dev)
52 {
53 	int i;
54 
55 	for (i = 0; i < ARRAY_SIZE(reg_save); i++)
56 		writel(reg_save[i][1], reg_base + reg_save[i][0]);
57 
58 	return 0;
59 }
60 
61 struct exynos_audss_clk_drvdata {
62 	unsigned int has_adma_clk:1;
63 	unsigned int has_mst_clk:1;
64 	unsigned int enable_epll:1;
65 	unsigned int num_clks;
66 };
67 
68 static const struct exynos_audss_clk_drvdata exynos4210_drvdata = {
69 	.num_clks	= EXYNOS_AUDSS_MAX_CLKS - 1,
70 	.enable_epll	= 1,
71 };
72 
73 static const struct exynos_audss_clk_drvdata exynos5410_drvdata = {
74 	.num_clks	= EXYNOS_AUDSS_MAX_CLKS - 1,
75 	.has_mst_clk	= 1,
76 };
77 
78 static const struct exynos_audss_clk_drvdata exynos5420_drvdata = {
79 	.num_clks	= EXYNOS_AUDSS_MAX_CLKS,
80 	.has_adma_clk	= 1,
81 	.enable_epll	= 1,
82 };
83 
84 static const struct of_device_id exynos_audss_clk_of_match[] = {
85 	{
86 		.compatible	= "samsung,exynos4210-audss-clock",
87 		.data		= &exynos4210_drvdata,
88 	}, {
89 		.compatible	= "samsung,exynos5250-audss-clock",
90 		.data		= &exynos4210_drvdata,
91 	}, {
92 		.compatible	= "samsung,exynos5410-audss-clock",
93 		.data		= &exynos5410_drvdata,
94 	}, {
95 		.compatible	= "samsung,exynos5420-audss-clock",
96 		.data		= &exynos5420_drvdata,
97 	},
98 	{ },
99 };
100 MODULE_DEVICE_TABLE(of, exynos_audss_clk_of_match);
101 
102 static void exynos_audss_clk_teardown(void)
103 {
104 	int i;
105 
106 	for (i = EXYNOS_MOUT_AUDSS; i < EXYNOS_DOUT_SRP; i++) {
107 		if (!IS_ERR(clk_data->hws[i]))
108 			clk_hw_unregister_mux(clk_data->hws[i]);
109 	}
110 
111 	for (; i < EXYNOS_SRP_CLK; i++) {
112 		if (!IS_ERR(clk_data->hws[i]))
113 			clk_hw_unregister_divider(clk_data->hws[i]);
114 	}
115 
116 	for (; i < clk_data->num; i++) {
117 		if (!IS_ERR(clk_data->hws[i]))
118 			clk_hw_unregister_gate(clk_data->hws[i]);
119 	}
120 }
121 
122 /* register exynos_audss clocks */
123 static int exynos_audss_clk_probe(struct platform_device *pdev)
124 {
125 	const char *mout_audss_p[] = {"fin_pll", "fout_epll"};
126 	const char *mout_i2s_p[] = {"mout_audss", "cdclk0", "sclk_audio0"};
127 	const char *sclk_pcm_p = "sclk_pcm0";
128 	struct clk *pll_ref, *pll_in, *cdclk, *sclk_audio, *sclk_pcm_in;
129 	const struct exynos_audss_clk_drvdata *variant;
130 	struct clk_hw **clk_table;
131 	struct device *dev = &pdev->dev;
132 	int i, ret = 0;
133 
134 	variant = of_device_get_match_data(&pdev->dev);
135 	if (!variant)
136 		return -EINVAL;
137 
138 	reg_base = devm_platform_ioremap_resource(pdev, 0);
139 	if (IS_ERR(reg_base))
140 		return PTR_ERR(reg_base);
141 
142 	epll = ERR_PTR(-ENODEV);
143 
144 	clk_data = devm_kzalloc(dev,
145 				struct_size(clk_data, hws,
146 					    EXYNOS_AUDSS_MAX_CLKS),
147 				GFP_KERNEL);
148 	if (!clk_data)
149 		return -ENOMEM;
150 
151 	clk_data->num = variant->num_clks;
152 	clk_table = clk_data->hws;
153 
154 	pll_ref = devm_clk_get(dev, "pll_ref");
155 	pll_in = devm_clk_get(dev, "pll_in");
156 	if (!IS_ERR(pll_ref))
157 		mout_audss_p[0] = __clk_get_name(pll_ref);
158 	if (!IS_ERR(pll_in)) {
159 		mout_audss_p[1] = __clk_get_name(pll_in);
160 
161 		if (variant->enable_epll) {
162 			epll = pll_in;
163 
164 			ret = clk_prepare_enable(epll);
165 			if (ret) {
166 				dev_err(dev,
167 					"failed to prepare the epll clock\n");
168 				return ret;
169 			}
170 		}
171 	}
172 
173 	/*
174 	 * Enable runtime PM here to allow the clock core using runtime PM
175 	 * for the registered clocks. Additionally, we increase the runtime
176 	 * PM usage count before registering the clocks, to prevent the
177 	 * clock core from runtime suspending the device.
178 	 */
179 	pm_runtime_get_noresume(dev);
180 	pm_runtime_set_active(dev);
181 	pm_runtime_enable(dev);
182 
183 	clk_table[EXYNOS_MOUT_AUDSS] = clk_hw_register_mux(dev, "mout_audss",
184 				mout_audss_p, ARRAY_SIZE(mout_audss_p),
185 				CLK_SET_RATE_NO_REPARENT | CLK_SET_RATE_PARENT,
186 				reg_base + ASS_CLK_SRC, 0, 1, 0, &lock);
187 
188 	cdclk = devm_clk_get(dev, "cdclk");
189 	sclk_audio = devm_clk_get(dev, "sclk_audio");
190 	if (!IS_ERR(cdclk))
191 		mout_i2s_p[1] = __clk_get_name(cdclk);
192 	if (!IS_ERR(sclk_audio))
193 		mout_i2s_p[2] = __clk_get_name(sclk_audio);
194 	clk_table[EXYNOS_MOUT_I2S] = clk_hw_register_mux(dev, "mout_i2s",
195 				mout_i2s_p, ARRAY_SIZE(mout_i2s_p),
196 				CLK_SET_RATE_NO_REPARENT,
197 				reg_base + ASS_CLK_SRC, 2, 2, 0, &lock);
198 
199 	clk_table[EXYNOS_DOUT_SRP] = clk_hw_register_divider(dev, "dout_srp",
200 				"mout_audss", CLK_SET_RATE_PARENT,
201 				reg_base + ASS_CLK_DIV, 0, 4, 0, &lock);
202 
203 	clk_table[EXYNOS_DOUT_AUD_BUS] = clk_hw_register_divider(dev,
204 				"dout_aud_bus", "dout_srp", CLK_SET_RATE_PARENT,
205 				reg_base + ASS_CLK_DIV, 4, 4, 0, &lock);
206 
207 	clk_table[EXYNOS_DOUT_I2S] = clk_hw_register_divider(dev, "dout_i2s",
208 				"mout_i2s", 0, reg_base + ASS_CLK_DIV, 8, 4, 0,
209 				&lock);
210 
211 	clk_table[EXYNOS_SRP_CLK] = clk_hw_register_gate(dev, "srp_clk",
212 				"dout_srp", CLK_SET_RATE_PARENT,
213 				reg_base + ASS_CLK_GATE, 0, 0, &lock);
214 
215 	clk_table[EXYNOS_I2S_BUS] = clk_hw_register_gate(dev, "i2s_bus",
216 				"dout_aud_bus", CLK_SET_RATE_PARENT,
217 				reg_base + ASS_CLK_GATE, 2, 0, &lock);
218 
219 	clk_table[EXYNOS_SCLK_I2S] = clk_hw_register_gate(dev, "sclk_i2s",
220 				"dout_i2s", CLK_SET_RATE_PARENT,
221 				reg_base + ASS_CLK_GATE, 3, 0, &lock);
222 
223 	clk_table[EXYNOS_PCM_BUS] = clk_hw_register_gate(dev, "pcm_bus",
224 				 "sclk_pcm", CLK_SET_RATE_PARENT,
225 				reg_base + ASS_CLK_GATE, 4, 0, &lock);
226 
227 	sclk_pcm_in = devm_clk_get(dev, "sclk_pcm_in");
228 	if (!IS_ERR(sclk_pcm_in))
229 		sclk_pcm_p = __clk_get_name(sclk_pcm_in);
230 	clk_table[EXYNOS_SCLK_PCM] = clk_hw_register_gate(dev, "sclk_pcm",
231 				sclk_pcm_p, CLK_SET_RATE_PARENT,
232 				reg_base + ASS_CLK_GATE, 5, 0, &lock);
233 
234 	if (variant->has_adma_clk) {
235 		clk_table[EXYNOS_ADMA] = clk_hw_register_gate(dev, "adma",
236 				"dout_srp", CLK_SET_RATE_PARENT,
237 				reg_base + ASS_CLK_GATE, 9, 0, &lock);
238 	}
239 
240 	for (i = 0; i < clk_data->num; i++) {
241 		if (IS_ERR(clk_table[i])) {
242 			dev_err(dev, "failed to register clock %d\n", i);
243 			ret = PTR_ERR(clk_table[i]);
244 			goto unregister;
245 		}
246 	}
247 
248 	ret = of_clk_add_hw_provider(dev->of_node, of_clk_hw_onecell_get,
249 				     clk_data);
250 	if (ret) {
251 		dev_err(dev, "failed to add clock provider\n");
252 		goto unregister;
253 	}
254 
255 	pm_runtime_put_sync(dev);
256 
257 	return 0;
258 
259 unregister:
260 	exynos_audss_clk_teardown();
261 	pm_runtime_put_sync(dev);
262 	pm_runtime_disable(dev);
263 
264 	if (!IS_ERR(epll))
265 		clk_disable_unprepare(epll);
266 
267 	return ret;
268 }
269 
270 static void exynos_audss_clk_remove(struct platform_device *pdev)
271 {
272 	of_clk_del_provider(pdev->dev.of_node);
273 
274 	exynos_audss_clk_teardown();
275 	pm_runtime_disable(&pdev->dev);
276 
277 	if (!IS_ERR(epll))
278 		clk_disable_unprepare(epll);
279 }
280 
281 static const struct dev_pm_ops exynos_audss_clk_pm_ops = {
282 	SET_RUNTIME_PM_OPS(exynos_audss_clk_suspend, exynos_audss_clk_resume,
283 			   NULL)
284 	SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
285 				     pm_runtime_force_resume)
286 };
287 
288 static struct platform_driver exynos_audss_clk_driver = {
289 	.driver	= {
290 		.name = "exynos-audss-clk",
291 		.of_match_table = exynos_audss_clk_of_match,
292 		.pm = &exynos_audss_clk_pm_ops,
293 	},
294 	.probe = exynos_audss_clk_probe,
295 	.remove = exynos_audss_clk_remove,
296 };
297 
298 module_platform_driver(exynos_audss_clk_driver);
299 
300 MODULE_AUTHOR("Padmavathi Venna <padma.v@samsung.com>");
301 MODULE_DESCRIPTION("Exynos Audio Subsystem Clock Controller");
302 MODULE_LICENSE("GPL v2");
303 MODULE_ALIAS("platform:exynos-audss-clk");
304