xref: /linux/drivers/clk/sprd/common.c (revision 578ba5d3)
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/platform_device.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 	.fast_io	= true,
21 };
22 
sprd_clk_set_regmap(const struct sprd_clk_desc * desc,struct regmap * regmap)23 static void sprd_clk_set_regmap(const struct sprd_clk_desc *desc,
24 			 struct regmap *regmap)
25 {
26 	int i;
27 	struct sprd_clk_common *cclk;
28 
29 	for (i = 0; i < desc->num_clk_clks; i++) {
30 		cclk = desc->clk_clks[i];
31 		if (!cclk)
32 			continue;
33 
34 		cclk->regmap = regmap;
35 	}
36 }
37 
sprd_clk_regmap_init(struct platform_device * pdev,const struct sprd_clk_desc * desc)38 int sprd_clk_regmap_init(struct platform_device *pdev,
39 			 const struct sprd_clk_desc *desc)
40 {
41 	void __iomem *base;
42 	struct device *dev = &pdev->dev;
43 	struct device_node *node = dev->of_node, *np;
44 	struct regmap *regmap;
45 	struct resource *res;
46 	struct regmap_config reg_config = sprdclk_regmap_config;
47 
48 	if (of_property_present(node, "sprd,syscon")) {
49 		regmap = syscon_regmap_lookup_by_phandle(node, "sprd,syscon");
50 		if (IS_ERR(regmap)) {
51 			pr_err("%s: failed to get syscon regmap\n", __func__);
52 			return PTR_ERR(regmap);
53 		}
54 	} else if (of_device_is_compatible(np =	of_get_parent(node), "syscon") ||
55 		   (of_node_put(np), 0)) {
56 		regmap = device_node_to_regmap(np);
57 		of_node_put(np);
58 		if (IS_ERR(regmap)) {
59 			dev_err(dev, "failed to get regmap from its parent.\n");
60 			return PTR_ERR(regmap);
61 		}
62 	} else {
63 		base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
64 		if (IS_ERR(base))
65 			return PTR_ERR(base);
66 
67 		reg_config.max_register = resource_size(res) - reg_config.reg_stride;
68 
69 		regmap = devm_regmap_init_mmio(&pdev->dev, base,
70 					       &reg_config);
71 		if (IS_ERR(regmap)) {
72 			pr_err("failed to init regmap\n");
73 			return PTR_ERR(regmap);
74 		}
75 	}
76 
77 	sprd_clk_set_regmap(desc, regmap);
78 
79 	return 0;
80 }
81 EXPORT_SYMBOL_GPL(sprd_clk_regmap_init);
82 
sprd_clk_probe(struct device * dev,struct clk_hw_onecell_data * clkhw)83 int sprd_clk_probe(struct device *dev, struct clk_hw_onecell_data *clkhw)
84 {
85 	int i, ret;
86 	struct clk_hw *hw;
87 
88 	for (i = 0; i < clkhw->num; i++) {
89 		const char *name;
90 
91 		hw = clkhw->hws[i];
92 		if (!hw)
93 			continue;
94 
95 		name = hw->init->name;
96 		ret = devm_clk_hw_register(dev, hw);
97 		if (ret) {
98 			dev_err(dev, "Couldn't register clock %d - %s\n",
99 				i, name);
100 			return ret;
101 		}
102 	}
103 
104 	ret = devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, clkhw);
105 	if (ret)
106 		dev_err(dev, "Failed to add clock provider\n");
107 
108 	return ret;
109 }
110 EXPORT_SYMBOL_GPL(sprd_clk_probe);
111 
112 MODULE_DESCRIPTION("Spreadtrum clock infrastructure");
113 MODULE_LICENSE("GPL v2");
114