xref: /openbmc/linux/drivers/clk/sprd/common.c (revision 1edd0337)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Spreadtrum clock infrastructure
4 //
5 // Copyright (C) 2017 Spreadtrum, Inc.
6 // Author: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
7 
8 #include <linux/mfd/syscon.h>
9 #include <linux/module.h>
10 #include <linux/of_address.h>
11 #include <linux/of_platform.h>
12 #include <linux/regmap.h>
13 
14 #include "common.h"
15 
16 static const struct regmap_config sprdclk_regmap_config = {
17 	.reg_bits	= 32,
18 	.reg_stride	= 4,
19 	.val_bits	= 32,
20 	.max_register	= 0xffff,
21 	.fast_io	= true,
22 };
23 
24 static void sprd_clk_set_regmap(const struct sprd_clk_desc *desc,
25 			 struct regmap *regmap)
26 {
27 	int i;
28 	struct sprd_clk_common *cclk;
29 
30 	for (i = 0; i < desc->num_clk_clks; i++) {
31 		cclk = desc->clk_clks[i];
32 		if (!cclk)
33 			continue;
34 
35 		cclk->regmap = regmap;
36 	}
37 }
38 
39 int sprd_clk_regmap_init(struct platform_device *pdev,
40 			 const struct sprd_clk_desc *desc)
41 {
42 	void __iomem *base;
43 	struct device *dev = &pdev->dev;
44 	struct device_node *node = dev->of_node, *np;
45 	struct regmap *regmap;
46 
47 	if (of_find_property(node, "sprd,syscon", NULL)) {
48 		regmap = syscon_regmap_lookup_by_phandle(node, "sprd,syscon");
49 		if (IS_ERR(regmap)) {
50 			pr_err("%s: failed to get syscon regmap\n", __func__);
51 			return PTR_ERR(regmap);
52 		}
53 	} else if (of_device_is_compatible(np =	of_get_parent(node), "syscon") ||
54 		   (of_node_put(np), 0)) {
55 		regmap = device_node_to_regmap(np);
56 		of_node_put(np);
57 		if (IS_ERR(regmap)) {
58 			dev_err(dev, "failed to get regmap from its parent.\n");
59 			return PTR_ERR(regmap);
60 		}
61 	} else {
62 		base = devm_platform_ioremap_resource(pdev, 0);
63 		if (IS_ERR(base))
64 			return PTR_ERR(base);
65 
66 		regmap = devm_regmap_init_mmio(&pdev->dev, base,
67 					       &sprdclk_regmap_config);
68 		if (IS_ERR(regmap)) {
69 			pr_err("failed to init regmap\n");
70 			return PTR_ERR(regmap);
71 		}
72 	}
73 
74 	sprd_clk_set_regmap(desc, regmap);
75 
76 	return 0;
77 }
78 EXPORT_SYMBOL_GPL(sprd_clk_regmap_init);
79 
80 int sprd_clk_probe(struct device *dev, struct clk_hw_onecell_data *clkhw)
81 {
82 	int i, ret;
83 	struct clk_hw *hw;
84 
85 	for (i = 0; i < clkhw->num; i++) {
86 		const char *name;
87 
88 		hw = clkhw->hws[i];
89 		if (!hw)
90 			continue;
91 
92 		name = hw->init->name;
93 		ret = devm_clk_hw_register(dev, hw);
94 		if (ret) {
95 			dev_err(dev, "Couldn't register clock %d - %s\n",
96 				i, name);
97 			return ret;
98 		}
99 	}
100 
101 	ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, clkhw);
102 	if (ret)
103 		dev_err(dev, "Failed to add clock provider\n");
104 
105 	return ret;
106 }
107 EXPORT_SYMBOL_GPL(sprd_clk_probe);
108 
109 MODULE_LICENSE("GPL v2");
110