xref: /linux/drivers/clk/axs10x/i2s_pll_clock.c (revision c7546e2c3cb739a3c1a2f5acaf9bb629d401afe5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Synopsys AXS10X SDP I2S PLL clock driver
4  *
5  * Copyright (C) 2016 Synopsys
6  */
7 
8 #include <linux/platform_device.h>
9 #include <linux/module.h>
10 #include <linux/clk-provider.h>
11 #include <linux/err.h>
12 #include <linux/device.h>
13 #include <linux/io.h>
14 #include <linux/of_address.h>
15 #include <linux/slab.h>
16 #include <linux/of.h>
17 
18 /* PLL registers addresses */
19 #define PLL_IDIV_REG	0x0
20 #define PLL_FBDIV_REG	0x4
21 #define PLL_ODIV0_REG	0x8
22 #define PLL_ODIV1_REG	0xC
23 
24 struct i2s_pll_cfg {
25 	unsigned int rate;
26 	unsigned int idiv;
27 	unsigned int fbdiv;
28 	unsigned int odiv0;
29 	unsigned int odiv1;
30 };
31 
32 static const struct i2s_pll_cfg i2s_pll_cfg_27m[] = {
33 	/* 27 Mhz */
34 	{ 1024000, 0x104, 0x451, 0x10E38, 0x2000 },
35 	{ 1411200, 0x104, 0x596, 0x10D35, 0x2000 },
36 	{ 1536000, 0x208, 0xA28, 0x10B2C, 0x2000 },
37 	{ 2048000, 0x82, 0x451, 0x10E38, 0x2000 },
38 	{ 2822400, 0x82, 0x596, 0x10D35, 0x2000 },
39 	{ 3072000, 0x104, 0xA28, 0x10B2C, 0x2000 },
40 	{ 2116800, 0x82, 0x3CF, 0x10C30, 0x2000 },
41 	{ 2304000, 0x104, 0x79E, 0x10B2C, 0x2000 },
42 	{ 0, 0, 0, 0, 0 },
43 };
44 
45 static const struct i2s_pll_cfg i2s_pll_cfg_28m[] = {
46 	/* 28.224 Mhz */
47 	{ 1024000, 0x82, 0x105, 0x107DF, 0x2000 },
48 	{ 1411200, 0x28A, 0x1, 0x10001, 0x2000 },
49 	{ 1536000, 0xA28, 0x187, 0x10042, 0x2000 },
50 	{ 2048000, 0x41, 0x105, 0x107DF, 0x2000 },
51 	{ 2822400, 0x145, 0x1, 0x10001, 0x2000 },
52 	{ 3072000, 0x514, 0x187, 0x10042, 0x2000 },
53 	{ 2116800, 0x514, 0x42, 0x10001, 0x2000 },
54 	{ 2304000, 0x619, 0x82, 0x10001, 0x2000 },
55 	{ 0, 0, 0, 0, 0 },
56 };
57 
58 struct i2s_pll_clk {
59 	void __iomem *base;
60 	struct clk_hw hw;
61 	struct device *dev;
62 };
63 
64 static inline void i2s_pll_write(struct i2s_pll_clk *clk, unsigned int reg,
65 		unsigned int val)
66 {
67 	writel_relaxed(val, clk->base + reg);
68 }
69 
70 static inline unsigned int i2s_pll_read(struct i2s_pll_clk *clk,
71 		unsigned int reg)
72 {
73 	return readl_relaxed(clk->base + reg);
74 }
75 
76 static inline struct i2s_pll_clk *to_i2s_pll_clk(struct clk_hw *hw)
77 {
78 	return container_of(hw, struct i2s_pll_clk, hw);
79 }
80 
81 static inline unsigned int i2s_pll_get_value(unsigned int val)
82 {
83 	return (val & 0x3F) + ((val >> 6) & 0x3F);
84 }
85 
86 static const struct i2s_pll_cfg *i2s_pll_get_cfg(unsigned long prate)
87 {
88 	switch (prate) {
89 	case 27000000:
90 		return i2s_pll_cfg_27m;
91 	case 28224000:
92 		return i2s_pll_cfg_28m;
93 	default:
94 		return NULL;
95 	}
96 }
97 
98 static unsigned long i2s_pll_recalc_rate(struct clk_hw *hw,
99 			unsigned long parent_rate)
100 {
101 	struct i2s_pll_clk *clk = to_i2s_pll_clk(hw);
102 	unsigned int idiv, fbdiv, odiv;
103 
104 	idiv = i2s_pll_get_value(i2s_pll_read(clk, PLL_IDIV_REG));
105 	fbdiv = i2s_pll_get_value(i2s_pll_read(clk, PLL_FBDIV_REG));
106 	odiv = i2s_pll_get_value(i2s_pll_read(clk, PLL_ODIV0_REG));
107 
108 	return ((parent_rate / idiv) * fbdiv) / odiv;
109 }
110 
111 static long i2s_pll_round_rate(struct clk_hw *hw, unsigned long rate,
112 			unsigned long *prate)
113 {
114 	struct i2s_pll_clk *clk = to_i2s_pll_clk(hw);
115 	const struct i2s_pll_cfg *pll_cfg = i2s_pll_get_cfg(*prate);
116 	int i;
117 
118 	if (!pll_cfg) {
119 		dev_err(clk->dev, "invalid parent rate=%ld\n", *prate);
120 		return -EINVAL;
121 	}
122 
123 	for (i = 0; pll_cfg[i].rate != 0; i++)
124 		if (pll_cfg[i].rate == rate)
125 			return rate;
126 
127 	return -EINVAL;
128 }
129 
130 static int i2s_pll_set_rate(struct clk_hw *hw, unsigned long rate,
131 			unsigned long parent_rate)
132 {
133 	struct i2s_pll_clk *clk = to_i2s_pll_clk(hw);
134 	const struct i2s_pll_cfg *pll_cfg = i2s_pll_get_cfg(parent_rate);
135 	int i;
136 
137 	if (!pll_cfg) {
138 		dev_err(clk->dev, "invalid parent rate=%ld\n", parent_rate);
139 		return -EINVAL;
140 	}
141 
142 	for (i = 0; pll_cfg[i].rate != 0; i++) {
143 		if (pll_cfg[i].rate == rate) {
144 			i2s_pll_write(clk, PLL_IDIV_REG, pll_cfg[i].idiv);
145 			i2s_pll_write(clk, PLL_FBDIV_REG, pll_cfg[i].fbdiv);
146 			i2s_pll_write(clk, PLL_ODIV0_REG, pll_cfg[i].odiv0);
147 			i2s_pll_write(clk, PLL_ODIV1_REG, pll_cfg[i].odiv1);
148 			return 0;
149 		}
150 	}
151 
152 	dev_err(clk->dev, "invalid rate=%ld, parent_rate=%ld\n", rate,
153 			parent_rate);
154 	return -EINVAL;
155 }
156 
157 static const struct clk_ops i2s_pll_ops = {
158 	.recalc_rate = i2s_pll_recalc_rate,
159 	.round_rate = i2s_pll_round_rate,
160 	.set_rate = i2s_pll_set_rate,
161 };
162 
163 static int i2s_pll_clk_probe(struct platform_device *pdev)
164 {
165 	struct device *dev = &pdev->dev;
166 	struct device_node *node = dev->of_node;
167 	const char *clk_name;
168 	const char *parent_name;
169 	struct clk *clk;
170 	struct i2s_pll_clk *pll_clk;
171 	struct clk_init_data init;
172 
173 	pll_clk = devm_kzalloc(dev, sizeof(*pll_clk), GFP_KERNEL);
174 	if (!pll_clk)
175 		return -ENOMEM;
176 
177 	pll_clk->base = devm_platform_ioremap_resource(pdev, 0);
178 	if (IS_ERR(pll_clk->base))
179 		return PTR_ERR(pll_clk->base);
180 
181 	memset(&init, 0, sizeof(init));
182 	clk_name = node->name;
183 	init.name = clk_name;
184 	init.ops = &i2s_pll_ops;
185 	parent_name = of_clk_get_parent_name(node, 0);
186 	init.parent_names = &parent_name;
187 	init.num_parents = 1;
188 	pll_clk->hw.init = &init;
189 	pll_clk->dev = dev;
190 
191 	clk = devm_clk_register(dev, &pll_clk->hw);
192 	if (IS_ERR(clk)) {
193 		dev_err(dev, "failed to register %s clock (%ld)\n",
194 				clk_name, PTR_ERR(clk));
195 		return PTR_ERR(clk);
196 	}
197 
198 	return of_clk_add_provider(node, of_clk_src_simple_get, clk);
199 }
200 
201 static void i2s_pll_clk_remove(struct platform_device *pdev)
202 {
203 	of_clk_del_provider(pdev->dev.of_node);
204 }
205 
206 static const struct of_device_id i2s_pll_clk_id[] = {
207 	{ .compatible = "snps,axs10x-i2s-pll-clock", },
208 	{ },
209 };
210 MODULE_DEVICE_TABLE(of, i2s_pll_clk_id);
211 
212 static struct platform_driver i2s_pll_clk_driver = {
213 	.driver = {
214 		.name = "axs10x-i2s-pll-clock",
215 		.of_match_table = i2s_pll_clk_id,
216 	},
217 	.probe = i2s_pll_clk_probe,
218 	.remove = i2s_pll_clk_remove,
219 };
220 module_platform_driver(i2s_pll_clk_driver);
221 
222 MODULE_AUTHOR("Jose Abreu <joabreu@synopsys.com>");
223 MODULE_DESCRIPTION("Synopsys AXS10X SDP I2S PLL Clock Driver");
224 MODULE_LICENSE("GPL v2");
225