1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Clock driver for the ARM Integrator/IM-PD1 board
4 * Copyright (C) 2012-2013 Linus Walleij
5 */
6 #include <linux/clk-provider.h>
7 #include <linux/clkdev.h>
8 #include <linux/err.h>
9 #include <linux/io.h>
10 #include <linux/platform_device.h>
11 #include <linux/module.h>
12 #include <linux/mfd/syscon.h>
13 #include <linux/regmap.h>
14
15 #include "icst.h"
16 #include "clk-icst.h"
17
18 #define IMPD1_OSC1 0x00
19 #define IMPD1_OSC2 0x04
20 #define IMPD1_LOCK 0x08
21
22 /*
23 * There are two VCO's on the IM-PD1
24 */
25
26 static const struct icst_params impd1_vco1_params = {
27 .ref = 24000000, /* 24 MHz */
28 .vco_max = ICST525_VCO_MAX_3V,
29 .vco_min = ICST525_VCO_MIN,
30 .vd_min = 12,
31 .vd_max = 519,
32 .rd_min = 3,
33 .rd_max = 120,
34 .s2div = icst525_s2div,
35 .idx2s = icst525_idx2s,
36 };
37
38 static const struct clk_icst_desc impd1_icst1_desc = {
39 .params = &impd1_vco1_params,
40 .vco_offset = IMPD1_OSC1,
41 .lock_offset = IMPD1_LOCK,
42 };
43
44 static const struct icst_params impd1_vco2_params = {
45 .ref = 24000000, /* 24 MHz */
46 .vco_max = ICST525_VCO_MAX_3V,
47 .vco_min = ICST525_VCO_MIN,
48 .vd_min = 12,
49 .vd_max = 519,
50 .rd_min = 3,
51 .rd_max = 120,
52 .s2div = icst525_s2div,
53 .idx2s = icst525_idx2s,
54 };
55
56 static const struct clk_icst_desc impd1_icst2_desc = {
57 .params = &impd1_vco2_params,
58 .vco_offset = IMPD1_OSC2,
59 .lock_offset = IMPD1_LOCK,
60 };
61
integrator_impd1_clk_spawn(struct device * dev,struct device_node * parent,struct device_node * np)62 static int integrator_impd1_clk_spawn(struct device *dev,
63 struct device_node *parent,
64 struct device_node *np)
65 {
66 struct regmap *map;
67 struct clk *clk = ERR_PTR(-EINVAL);
68 const char *name = np->name;
69 const char *parent_name;
70 const struct clk_icst_desc *desc;
71 int ret;
72
73 map = syscon_node_to_regmap(parent);
74 if (IS_ERR(map)) {
75 pr_err("no regmap for syscon IM-PD1 ICST clock parent\n");
76 return PTR_ERR(map);
77 }
78
79 if (of_device_is_compatible(np, "arm,impd1-vco1")) {
80 desc = &impd1_icst1_desc;
81 } else if (of_device_is_compatible(np, "arm,impd1-vco2")) {
82 desc = &impd1_icst2_desc;
83 } else {
84 dev_err(dev, "not a clock node %s\n", name);
85 return -ENODEV;
86 }
87
88 of_property_read_string(np, "clock-output-names", &name);
89 parent_name = of_clk_get_parent_name(np, 0);
90 clk = icst_clk_setup(NULL, desc, name, parent_name, map,
91 ICST_INTEGRATOR_IM_PD1);
92 if (!IS_ERR(clk)) {
93 of_clk_add_provider(np, of_clk_src_simple_get, clk);
94 ret = 0;
95 } else {
96 dev_err(dev, "error setting up IM-PD1 ICST clock\n");
97 ret = PTR_ERR(clk);
98 }
99
100 return ret;
101 }
102
integrator_impd1_clk_probe(struct platform_device * pdev)103 static int integrator_impd1_clk_probe(struct platform_device *pdev)
104 {
105 struct device *dev = &pdev->dev;
106 struct device_node *np = dev->of_node;
107 struct device_node *child;
108 int ret = 0;
109
110 for_each_available_child_of_node(np, child) {
111 ret = integrator_impd1_clk_spawn(dev, np, child);
112 if (ret) {
113 of_node_put(child);
114 break;
115 }
116 }
117
118 return ret;
119 }
120
121 static const struct of_device_id impd1_syscon_match[] = {
122 { .compatible = "arm,im-pd1-syscon", },
123 {}
124 };
125 MODULE_DEVICE_TABLE(of, impd1_syscon_match);
126
127 static struct platform_driver impd1_clk_driver = {
128 .driver = {
129 .name = "impd1-clk",
130 .of_match_table = impd1_syscon_match,
131 },
132 .probe = integrator_impd1_clk_probe,
133 };
134 builtin_platform_driver(impd1_clk_driver);
135
136 MODULE_AUTHOR("Linus Walleij <linusw@kernel.org>");
137 MODULE_DESCRIPTION("Arm IM-PD1 module clock driver");
138 MODULE_LICENSE("GPL v2");
139