xref: /openbmc/linux/drivers/clk/ux500/abx500-clk.c (revision d0e22329)
1 /*
2  * abx500 clock implementation for ux500 platform.
3  *
4  * Copyright (C) 2012 ST-Ericsson SA
5  * Author: Ulf Hansson <ulf.hansson@linaro.org>
6  *
7  * License terms: GNU General Public License (GPL) version 2
8  */
9 
10 #include <linux/err.h>
11 #include <linux/module.h>
12 #include <linux/device.h>
13 #include <linux/of.h>
14 #include <linux/platform_device.h>
15 #include <linux/mfd/abx500/ab8500.h>
16 #include <linux/mfd/abx500/ab8500-sysctrl.h>
17 #include <linux/clkdev.h>
18 #include <linux/clk-provider.h>
19 #include <dt-bindings/clock/ste-ab8500.h>
20 #include "clk.h"
21 
22 #define AB8500_NUM_CLKS 6
23 
24 static struct clk *ab8500_clks[AB8500_NUM_CLKS];
25 static struct clk_onecell_data ab8500_clk_data;
26 
27 /* Clock definitions for ab8500 */
28 static int ab8500_reg_clks(struct device *dev)
29 {
30 	int ret;
31 	struct clk *clk;
32 	struct device_node *np = dev->of_node;
33 	const char *intclk_parents[] = {"ab8500_sysclk", "ulpclk"};
34 	u16 intclk_reg_sel[] = {0 , AB8500_SYSULPCLKCTRL1};
35 	u8 intclk_reg_mask[] = {0 , AB8500_SYSULPCLKCTRL1_SYSULPCLKINTSEL_MASK};
36 	u8 intclk_reg_bits[] = {
37 		0 ,
38 		(1 << AB8500_SYSULPCLKCTRL1_SYSULPCLKINTSEL_SHIFT)
39 	};
40 
41 	/* Enable SWAT */
42 	ret = ab8500_sysctrl_set(AB8500_SWATCTRL, AB8500_SWATCTRL_SWATENABLE);
43 	if (ret)
44 		return ret;
45 
46 	/* ab8500_sysclk2 */
47 	clk = clk_reg_sysctrl_gate(dev , "ab8500_sysclk2", "ab8500_sysclk",
48 		AB8500_SYSULPCLKCTRL1, AB8500_SYSULPCLKCTRL1_SYSCLKBUF2REQ,
49 		AB8500_SYSULPCLKCTRL1_SYSCLKBUF2REQ, 0, 0);
50 	ab8500_clks[AB8500_SYSCLK_BUF2] = clk;
51 
52 	/* ab8500_sysclk3 */
53 	clk = clk_reg_sysctrl_gate(dev , "ab8500_sysclk3", "ab8500_sysclk",
54 		AB8500_SYSULPCLKCTRL1, AB8500_SYSULPCLKCTRL1_SYSCLKBUF3REQ,
55 		AB8500_SYSULPCLKCTRL1_SYSCLKBUF3REQ, 0, 0);
56 	ab8500_clks[AB8500_SYSCLK_BUF3] = clk;
57 
58 	/* ab8500_sysclk4 */
59 	clk = clk_reg_sysctrl_gate(dev , "ab8500_sysclk4", "ab8500_sysclk",
60 		AB8500_SYSULPCLKCTRL1, AB8500_SYSULPCLKCTRL1_SYSCLKBUF4REQ,
61 		AB8500_SYSULPCLKCTRL1_SYSCLKBUF4REQ, 0, 0);
62 	ab8500_clks[AB8500_SYSCLK_BUF4] = clk;
63 
64 	/* ab_ulpclk */
65 	clk = clk_reg_sysctrl_gate_fixed_rate(dev, "ulpclk", NULL,
66 		AB8500_SYSULPCLKCTRL1, AB8500_SYSULPCLKCTRL1_ULPCLKREQ,
67 		AB8500_SYSULPCLKCTRL1_ULPCLKREQ,
68 		38400000, 9000, 0);
69 	ab8500_clks[AB8500_SYSCLK_ULP] = clk;
70 
71 	/* ab8500_intclk */
72 	clk = clk_reg_sysctrl_set_parent(dev , "intclk", intclk_parents, 2,
73 		intclk_reg_sel, intclk_reg_mask, intclk_reg_bits, 0);
74 	ab8500_clks[AB8500_SYSCLK_INT] = clk;
75 
76 	/* ab8500_audioclk */
77 	clk = clk_reg_sysctrl_gate(dev , "audioclk", "intclk",
78 		AB8500_SYSULPCLKCTRL1, AB8500_SYSULPCLKCTRL1_AUDIOCLKENA,
79 		AB8500_SYSULPCLKCTRL1_AUDIOCLKENA, 0, 0);
80 	ab8500_clks[AB8500_SYSCLK_AUDIO] = clk;
81 
82 	ab8500_clk_data.clks = ab8500_clks;
83 	ab8500_clk_data.clk_num = ARRAY_SIZE(ab8500_clks);
84 	of_clk_add_provider(np, of_clk_src_onecell_get, &ab8500_clk_data);
85 
86 	dev_info(dev, "registered clocks for ab850x\n");
87 
88 	return 0;
89 }
90 
91 static int abx500_clk_probe(struct platform_device *pdev)
92 {
93 	struct ab8500 *parent = dev_get_drvdata(pdev->dev.parent);
94 	int ret;
95 
96 	if (is_ab8500(parent) || is_ab8505(parent)) {
97 		ret = ab8500_reg_clks(&pdev->dev);
98 	} else {
99 		dev_err(&pdev->dev, "non supported plf id\n");
100 		return -ENODEV;
101 	}
102 
103 	return ret;
104 }
105 
106 static const struct of_device_id abx500_clk_match[] = {
107 	{ .compatible = "stericsson,ab8500-clk", },
108 	{}
109 };
110 
111 static struct platform_driver abx500_clk_driver = {
112 	.driver = {
113 		.name = "abx500-clk",
114 		.of_match_table = abx500_clk_match,
115 	},
116 	.probe	= abx500_clk_probe,
117 };
118 
119 static int __init abx500_clk_init(void)
120 {
121 	return platform_driver_register(&abx500_clk_driver);
122 }
123 arch_initcall(abx500_clk_init);
124 
125 MODULE_AUTHOR("Ulf Hansson <ulf.hansson@linaro.org");
126 MODULE_DESCRIPTION("ABX500 clk driver");
127 MODULE_LICENSE("GPL v2");
128