xref: /linux/drivers/clk/clk-twl6040.c (revision 5c757456c16ce056a40a120e63235bc00c94ee7f)
1 /*
2 * TWL6040 clock module driver for OMAP4 McPDM functional clock
3 *
4 * Copyright (C) 2012 Texas Instruments Inc.
5 * Peter Ujfalusi <peter.ujfalusi@ti.com>
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * version 2 as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
19 * 02110-1301 USA
20 *
21 */
22 
23 #include <linux/clk.h>
24 #include <linux/module.h>
25 #include <linux/slab.h>
26 #include <linux/platform_device.h>
27 #include <linux/mfd/twl6040.h>
28 #include <linux/clk-provider.h>
29 
30 struct twl6040_clk {
31 	struct twl6040 *twl6040;
32 	struct device *dev;
33 	struct clk_hw mcpdm_fclk;
34 	struct clk *clk;
35 	int enabled;
36 };
37 
38 static int twl6040_bitclk_is_enabled(struct clk_hw *hw)
39 {
40 	struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk,
41 						       mcpdm_fclk);
42 	return twl6040_clk->enabled;
43 }
44 
45 static int twl6040_bitclk_prepare(struct clk_hw *hw)
46 {
47 	struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk,
48 						       mcpdm_fclk);
49 	int ret;
50 
51 	ret = twl6040_power(twl6040_clk->twl6040, 1);
52 	if (!ret)
53 		twl6040_clk->enabled = 1;
54 
55 	return ret;
56 }
57 
58 static void twl6040_bitclk_unprepare(struct clk_hw *hw)
59 {
60 	struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk,
61 						       mcpdm_fclk);
62 	int ret;
63 
64 	ret = twl6040_power(twl6040_clk->twl6040, 0);
65 	if (!ret)
66 		twl6040_clk->enabled = 0;
67 }
68 
69 static const struct clk_ops twl6040_mcpdm_ops = {
70 	.is_enabled = twl6040_bitclk_is_enabled,
71 	.prepare = twl6040_bitclk_prepare,
72 	.unprepare = twl6040_bitclk_unprepare,
73 };
74 
75 static struct clk_init_data wm831x_clkout_init = {
76 	.name = "mcpdm_fclk",
77 	.ops = &twl6040_mcpdm_ops,
78 	.flags = CLK_IS_ROOT,
79 };
80 
81 static int twl6040_clk_probe(struct platform_device *pdev)
82 {
83 	struct twl6040 *twl6040 = dev_get_drvdata(pdev->dev.parent);
84 	struct twl6040_clk *clkdata;
85 
86 	clkdata = devm_kzalloc(&pdev->dev, sizeof(*clkdata), GFP_KERNEL);
87 	if (!clkdata)
88 		return -ENOMEM;
89 
90 	clkdata->dev = &pdev->dev;
91 	clkdata->twl6040 = twl6040;
92 
93 	clkdata->mcpdm_fclk.init = &wm831x_clkout_init;
94 	clkdata->clk = devm_clk_register(&pdev->dev, &clkdata->mcpdm_fclk);
95 	if (IS_ERR(clkdata->clk))
96 		return PTR_ERR(clkdata->clk);
97 
98 	platform_set_drvdata(pdev, clkdata);
99 
100 	return 0;
101 }
102 
103 static struct platform_driver twl6040_clk_driver = {
104 	.driver = {
105 		.name = "twl6040-clk",
106 	},
107 	.probe = twl6040_clk_probe,
108 };
109 
110 module_platform_driver(twl6040_clk_driver);
111 
112 MODULE_DESCRIPTION("TWL6040 clock driver for McPDM functional clock");
113 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
114 MODULE_ALIAS("platform:twl6040-clk");
115 MODULE_LICENSE("GPL");
116