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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
30struct 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
38static 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
45static 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
58static 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
69static 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
75static struct clk_init_data wm831x_clkout_init = {
76 .name = "mcpdm_fclk",
77 .ops = &twl6040_mcpdm_ops,
78 .flags = CLK_IS_ROOT,
79};
80
81static 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 = 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
103static int twl6040_clk_remove(struct platform_device *pdev)
104{
105 struct twl6040_clk *clkdata = platform_get_drvdata(pdev);
106
107 clk_unregister(clkdata->clk);
108
109 return 0;
110}
111
112static struct platform_driver twl6040_clk_driver = {
113 .driver = {
114 .name = "twl6040-clk",
115 .owner = THIS_MODULE,
116 },
117 .probe = twl6040_clk_probe,
118 .remove = twl6040_clk_remove,
119};
120
121module_platform_driver(twl6040_clk_driver);
122
123MODULE_DESCRIPTION("TWL6040 clock driver for McPDM functional clock");
124MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
125MODULE_ALIAS("platform:twl6040-clk");
126MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3* TWL6040 clock module driver for OMAP4 McPDM functional clock
4*
5* Copyright (C) 2012 Texas Instruments Inc.
6* Peter Ujfalusi <peter.ujfalusi@ti.com>
7*/
8
9#include <linux/module.h>
10#include <linux/slab.h>
11#include <linux/platform_device.h>
12#include <linux/mfd/twl6040.h>
13#include <linux/clk-provider.h>
14
15struct twl6040_pdmclk {
16 struct twl6040 *twl6040;
17 struct device *dev;
18 struct clk_hw pdmclk_hw;
19 int enabled;
20};
21
22static int twl6040_pdmclk_is_prepared(struct clk_hw *hw)
23{
24 struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk,
25 pdmclk_hw);
26
27 return pdmclk->enabled;
28}
29
30static int twl6040_pdmclk_reset_one_clock(struct twl6040_pdmclk *pdmclk,
31 unsigned int reg)
32{
33 const u8 reset_mask = TWL6040_HPLLRST; /* Same for HPPLL and LPPLL */
34 int ret;
35
36 ret = twl6040_set_bits(pdmclk->twl6040, reg, reset_mask);
37 if (ret < 0)
38 return ret;
39
40 ret = twl6040_clear_bits(pdmclk->twl6040, reg, reset_mask);
41 if (ret < 0)
42 return ret;
43
44 return 0;
45}
46
47/*
48 * TWL6040A2 Phoenix Audio IC erratum #6: "PDM Clock Generation Issue At
49 * Cold Temperature". This affects cold boot and deeper idle states it
50 * seems. The workaround consists of resetting HPPLL and LPPLL.
51 */
52static int twl6040_pdmclk_quirk_reset_clocks(struct twl6040_pdmclk *pdmclk)
53{
54 int ret;
55
56 ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_HPPLLCTL);
57 if (ret)
58 return ret;
59
60 ret = twl6040_pdmclk_reset_one_clock(pdmclk, TWL6040_REG_LPPLLCTL);
61 if (ret)
62 return ret;
63
64 return 0;
65}
66
67static int twl6040_pdmclk_prepare(struct clk_hw *hw)
68{
69 struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk,
70 pdmclk_hw);
71 int ret;
72
73 ret = twl6040_power(pdmclk->twl6040, 1);
74 if (ret)
75 return ret;
76
77 ret = twl6040_pdmclk_quirk_reset_clocks(pdmclk);
78 if (ret)
79 goto out_err;
80
81 pdmclk->enabled = 1;
82
83 return 0;
84
85out_err:
86 dev_err(pdmclk->dev, "%s: error %i\n", __func__, ret);
87 twl6040_power(pdmclk->twl6040, 0);
88
89 return ret;
90}
91
92static void twl6040_pdmclk_unprepare(struct clk_hw *hw)
93{
94 struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk,
95 pdmclk_hw);
96 int ret;
97
98 ret = twl6040_power(pdmclk->twl6040, 0);
99 if (!ret)
100 pdmclk->enabled = 0;
101
102}
103
104static unsigned long twl6040_pdmclk_recalc_rate(struct clk_hw *hw,
105 unsigned long parent_rate)
106{
107 struct twl6040_pdmclk *pdmclk = container_of(hw, struct twl6040_pdmclk,
108 pdmclk_hw);
109
110 return twl6040_get_sysclk(pdmclk->twl6040);
111}
112
113static const struct clk_ops twl6040_pdmclk_ops = {
114 .is_prepared = twl6040_pdmclk_is_prepared,
115 .prepare = twl6040_pdmclk_prepare,
116 .unprepare = twl6040_pdmclk_unprepare,
117 .recalc_rate = twl6040_pdmclk_recalc_rate,
118};
119
120static const struct clk_init_data twl6040_pdmclk_init = {
121 .name = "pdmclk",
122 .ops = &twl6040_pdmclk_ops,
123 .flags = CLK_GET_RATE_NOCACHE,
124};
125
126static int twl6040_pdmclk_probe(struct platform_device *pdev)
127{
128 struct twl6040 *twl6040 = dev_get_drvdata(pdev->dev.parent);
129 struct twl6040_pdmclk *clkdata;
130 int ret;
131
132 clkdata = devm_kzalloc(&pdev->dev, sizeof(*clkdata), GFP_KERNEL);
133 if (!clkdata)
134 return -ENOMEM;
135
136 clkdata->dev = &pdev->dev;
137 clkdata->twl6040 = twl6040;
138
139 clkdata->pdmclk_hw.init = &twl6040_pdmclk_init;
140 ret = devm_clk_hw_register(&pdev->dev, &clkdata->pdmclk_hw);
141 if (ret)
142 return ret;
143
144 platform_set_drvdata(pdev, clkdata);
145
146 return devm_of_clk_add_hw_provider(&pdev->dev, of_clk_hw_simple_get,
147 &clkdata->pdmclk_hw);
148}
149
150static struct platform_driver twl6040_pdmclk_driver = {
151 .driver = {
152 .name = "twl6040-pdmclk",
153 },
154 .probe = twl6040_pdmclk_probe,
155};
156
157module_platform_driver(twl6040_pdmclk_driver);
158
159MODULE_DESCRIPTION("TWL6040 clock driver for McPDM functional clock");
160MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
161MODULE_ALIAS("platform:twl6040-pdmclk");
162MODULE_LICENSE("GPL");