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
20static DEFINE_SPINLOCK(lock);
21static void __iomem *reg_base;
22static 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 */
29static struct clk *epll;
30
31#define ASS_CLK_SRC 0x0
32#define ASS_CLK_DIV 0x4
33#define ASS_CLK_GATE 0x8
34
35static unsigned long reg_save[][2] = {
36	{ ASS_CLK_SRC,  0 },
37	{ ASS_CLK_DIV,  0 },
38	{ ASS_CLK_GATE, 0 },
39};
40
41static 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
51static 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
61struct 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
68static const struct exynos_audss_clk_drvdata exynos4210_drvdata = {
69	.num_clks	= EXYNOS_AUDSS_MAX_CLKS - 1,
70	.enable_epll	= 1,
71};
72
73static const struct exynos_audss_clk_drvdata exynos5410_drvdata = {
74	.num_clks	= EXYNOS_AUDSS_MAX_CLKS - 1,
75	.has_mst_clk	= 1,
76};
77
78static 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
84static 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};
100MODULE_DEVICE_TABLE(of, exynos_audss_clk_of_match);
101
102static 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 */
123static 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
259unregister:
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
270static 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
281static 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
288static 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_new = exynos_audss_clk_remove,
296};
297
298module_platform_driver(exynos_audss_clk_driver);
299
300MODULE_AUTHOR("Padmavathi Venna <padma.v@samsung.com>");
301MODULE_DESCRIPTION("Exynos Audio Subsystem Clock Controller");
302MODULE_LICENSE("GPL v2");
303MODULE_ALIAS("platform:exynos-audss-clk");
304