1 /*
2 * linux/drivers/media/platform/s5p-mfc/s5p_mfc_pm.c
3 *
4 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
5 * http://www.samsung.com/
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 */
12
13 #include <linux/clk.h>
14 #include <linux/err.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 #include "s5p_mfc_common.h"
18 #include "s5p_mfc_debug.h"
19 #include "s5p_mfc_pm.h"
20
21 static struct s5p_mfc_pm *pm;
22 static struct s5p_mfc_dev *p_dev;
23 static atomic_t clk_ref;
24
s5p_mfc_init_pm(struct s5p_mfc_dev * dev)25 int s5p_mfc_init_pm(struct s5p_mfc_dev *dev)
26 {
27 int i;
28
29 pm = &dev->pm;
30 p_dev = dev;
31
32 pm->num_clocks = dev->variant->num_clocks;
33 pm->clk_names = dev->variant->clk_names;
34 pm->device = &dev->plat_dev->dev;
35 pm->clock_gate = NULL;
36
37 /* clock control */
38 for (i = 0; i < pm->num_clocks; i++) {
39 pm->clocks[i] = devm_clk_get(pm->device, pm->clk_names[i]);
40 if (IS_ERR(pm->clocks[i])) {
41 mfc_err("Failed to get clock: %s\n",
42 pm->clk_names[i]);
43 return PTR_ERR(pm->clocks[i]);
44 }
45 }
46
47 if (dev->variant->use_clock_gating)
48 pm->clock_gate = pm->clocks[0];
49
50 pm_runtime_enable(pm->device);
51 atomic_set(&clk_ref, 0);
52 return 0;
53 }
54
s5p_mfc_final_pm(struct s5p_mfc_dev * dev)55 void s5p_mfc_final_pm(struct s5p_mfc_dev *dev)
56 {
57 pm_runtime_disable(pm->device);
58 }
59
s5p_mfc_clock_on(void)60 int s5p_mfc_clock_on(void)
61 {
62 atomic_inc(&clk_ref);
63 mfc_debug(3, "+ %d\n", atomic_read(&clk_ref));
64
65 return clk_enable(pm->clock_gate);
66 }
67
s5p_mfc_clock_off(void)68 void s5p_mfc_clock_off(void)
69 {
70 atomic_dec(&clk_ref);
71 mfc_debug(3, "- %d\n", atomic_read(&clk_ref));
72
73 clk_disable(pm->clock_gate);
74 }
75
s5p_mfc_power_on(void)76 int s5p_mfc_power_on(void)
77 {
78 int i, ret = 0;
79
80 ret = pm_runtime_get_sync(pm->device);
81 if (ret < 0)
82 return ret;
83
84 /* clock control */
85 for (i = 0; i < pm->num_clocks; i++) {
86 ret = clk_prepare_enable(pm->clocks[i]);
87 if (ret < 0) {
88 mfc_err("clock prepare failed for clock: %s\n",
89 pm->clk_names[i]);
90 i++;
91 goto err;
92 }
93 }
94
95 /* prepare for software clock gating */
96 clk_disable(pm->clock_gate);
97
98 return 0;
99 err:
100 while (--i > 0)
101 clk_disable_unprepare(pm->clocks[i]);
102 pm_runtime_put(pm->device);
103 return ret;
104 }
105
s5p_mfc_power_off(void)106 int s5p_mfc_power_off(void)
107 {
108 int i;
109
110 /* finish software clock gating */
111 clk_enable(pm->clock_gate);
112
113 for (i = 0; i < pm->num_clocks; i++)
114 clk_disable_unprepare(pm->clocks[i]);
115
116 return pm_runtime_put_sync(pm->device);
117 }
118
119