tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright (C) 2014 Free Electrons
3 *
4 * License Terms: GNU General Public License v2
5 * Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
6 *
7 * Allwinner A31 APB0 clock gates driver
8 *
9 */
10
11#include <linux/clk-provider.h>
12#include <linux/module.h>
13#include <linux/of.h>
14#include <linux/of_device.h>
15#include <linux/platform_device.h>
16
17#define SUN6I_APB0_GATES_MAX_SIZE 32
18
19struct gates_data {
20 DECLARE_BITMAP(mask, SUN6I_APB0_GATES_MAX_SIZE);
21};
22
23static const struct gates_data sun6i_a31_apb0_gates __initconst = {
24 .mask = {0x7F},
25};
26
27static const struct gates_data sun8i_a23_apb0_gates __initconst = {
28 .mask = {0x5D},
29};
30
31static const struct of_device_id sun6i_a31_apb0_gates_clk_dt_ids[] = {
32 { .compatible = "allwinner,sun6i-a31-apb0-gates-clk", .data = &sun6i_a31_apb0_gates },
33 { .compatible = "allwinner,sun8i-a23-apb0-gates-clk", .data = &sun8i_a23_apb0_gates },
34 { /* sentinel */ }
35};
36MODULE_DEVICE_TABLE(of, sun6i_a31_apb0_gates_clk_dt_ids);
37
38static int sun6i_a31_apb0_gates_clk_probe(struct platform_device *pdev)
39{
40 struct device_node *np = pdev->dev.of_node;
41 struct clk_onecell_data *clk_data;
42 const struct of_device_id *device;
43 const struct gates_data *data;
44 const char *clk_parent;
45 const char *clk_name;
46 struct resource *r;
47 void __iomem *reg;
48 int ngates;
49 int i;
50 int j = 0;
51
52 if (!np)
53 return -ENODEV;
54
55 device = of_match_device(sun6i_a31_apb0_gates_clk_dt_ids, &pdev->dev);
56 if (!device)
57 return -ENODEV;
58 data = device->data;
59
60 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
61 reg = devm_ioremap_resource(&pdev->dev, r);
62 if (IS_ERR(reg))
63 return PTR_ERR(reg);
64
65 clk_parent = of_clk_get_parent_name(np, 0);
66 if (!clk_parent)
67 return -EINVAL;
68
69 clk_data = devm_kzalloc(&pdev->dev, sizeof(struct clk_onecell_data),
70 GFP_KERNEL);
71 if (!clk_data)
72 return -ENOMEM;
73
74 /* Worst-case size approximation and memory allocation */
75 ngates = find_last_bit(data->mask, SUN6I_APB0_GATES_MAX_SIZE);
76 clk_data->clks = devm_kcalloc(&pdev->dev, (ngates + 1),
77 sizeof(struct clk *), GFP_KERNEL);
78 if (!clk_data->clks)
79 return -ENOMEM;
80
81 for_each_set_bit(i, data->mask, SUN6I_APB0_GATES_MAX_SIZE) {
82 of_property_read_string_index(np, "clock-output-names",
83 j, &clk_name);
84
85 clk_data->clks[i] = clk_register_gate(&pdev->dev, clk_name,
86 clk_parent, 0, reg, i,
87 0, NULL);
88 WARN_ON(IS_ERR(clk_data->clks[i]));
89
90 j++;
91 }
92
93 clk_data->clk_num = ngates + 1;
94
95 return of_clk_add_provider(np, of_clk_src_onecell_get, clk_data);
96}
97
98static struct platform_driver sun6i_a31_apb0_gates_clk_driver = {
99 .driver = {
100 .name = "sun6i-a31-apb0-gates-clk",
101 .of_match_table = sun6i_a31_apb0_gates_clk_dt_ids,
102 },
103 .probe = sun6i_a31_apb0_gates_clk_probe,
104};
105module_platform_driver(sun6i_a31_apb0_gates_clk_driver);
106
107MODULE_AUTHOR("Boris BREZILLON <boris.brezillon@free-electrons.com>");
108MODULE_DESCRIPTION("Allwinner A31 APB0 gate clocks driver");
109MODULE_LICENSE("GPL v2");