xref: /linux/drivers/clk/clk-twl6040.c (revision 95cd2ea7d54b41b0b2828587f108fe270d59eede)
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/module.h>
24 #include <linux/slab.h>
25 #include <linux/platform_device.h>
26 #include <linux/mfd/twl6040.h>
27 #include <linux/clk-provider.h>
28 
29 struct twl6040_clk {
30 	struct twl6040 *twl6040;
31 	struct device *dev;
32 	struct clk_hw mcpdm_fclk;
33 	struct clk *clk;
34 	int enabled;
35 };
36 
37 static int twl6040_bitclk_is_enabled(struct clk_hw *hw)
38 {
39 	struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk,
40 						       mcpdm_fclk);
41 	return twl6040_clk->enabled;
42 }
43 
44 static int twl6040_bitclk_prepare(struct clk_hw *hw)
45 {
46 	struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk,
47 						       mcpdm_fclk);
48 	int ret;
49 
50 	ret = twl6040_power(twl6040_clk->twl6040, 1);
51 	if (!ret)
52 		twl6040_clk->enabled = 1;
53 
54 	return ret;
55 }
56 
57 static void twl6040_bitclk_unprepare(struct clk_hw *hw)
58 {
59 	struct twl6040_clk *twl6040_clk = container_of(hw, struct twl6040_clk,
60 						       mcpdm_fclk);
61 	int ret;
62 
63 	ret = twl6040_power(twl6040_clk->twl6040, 0);
64 	if (!ret)
65 		twl6040_clk->enabled = 0;
66 }
67 
68 static const struct clk_ops twl6040_mcpdm_ops = {
69 	.is_enabled = twl6040_bitclk_is_enabled,
70 	.prepare = twl6040_bitclk_prepare,
71 	.unprepare = twl6040_bitclk_unprepare,
72 };
73 
74 static struct clk_init_data wm831x_clkout_init = {
75 	.name = "mcpdm_fclk",
76 	.ops = &twl6040_mcpdm_ops,
77 	.flags = CLK_IS_ROOT,
78 };
79 
80 static int twl6040_clk_probe(struct platform_device *pdev)
81 {
82 	struct twl6040 *twl6040 = dev_get_drvdata(pdev->dev.parent);
83 	struct twl6040_clk *clkdata;
84 
85 	clkdata = devm_kzalloc(&pdev->dev, sizeof(*clkdata), GFP_KERNEL);
86 	if (!clkdata)
87 		return -ENOMEM;
88 
89 	clkdata->dev = &pdev->dev;
90 	clkdata->twl6040 = twl6040;
91 
92 	clkdata->mcpdm_fclk.init = &wm831x_clkout_init;
93 	clkdata->clk = devm_clk_register(&pdev->dev, &clkdata->mcpdm_fclk);
94 	if (IS_ERR(clkdata->clk))
95 		return PTR_ERR(clkdata->clk);
96 
97 	platform_set_drvdata(pdev, clkdata);
98 
99 	return 0;
100 }
101 
102 static struct platform_driver twl6040_clk_driver = {
103 	.driver = {
104 		.name = "twl6040-clk",
105 	},
106 	.probe = twl6040_clk_probe,
107 };
108 
109 module_platform_driver(twl6040_clk_driver);
110 
111 MODULE_DESCRIPTION("TWL6040 clock driver for McPDM functional clock");
112 MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
113 MODULE_ALIAS("platform:twl6040-clk");
114 MODULE_LICENSE("GPL");
115