1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * linux/drivers/media/platform/samsung/s5p-mfc/s5p_mfc_pm.c
4 *
5 * Copyright (c) 2010 Samsung Electronics Co., Ltd.
6 * http://www.samsung.com/
7 */
8
9 #include <linux/clk.h>
10 #include <linux/err.h>
11 #include <linux/platform_device.h>
12 #include <linux/pm_runtime.h>
13 #include "s5p_mfc_common.h"
14 #include "s5p_mfc_debug.h"
15 #include "s5p_mfc_pm.h"
16
17 static struct s5p_mfc_pm *pm;
18 static struct s5p_mfc_dev *p_dev;
19 static atomic_t clk_ref;
20
s5p_mfc_init_pm(struct s5p_mfc_dev * dev)21 int s5p_mfc_init_pm(struct s5p_mfc_dev *dev)
22 {
23 int i;
24
25 pm = &dev->pm;
26 p_dev = dev;
27
28 pm->num_clocks = dev->variant->num_clocks;
29 pm->clk_names = dev->variant->clk_names;
30 pm->device = &dev->plat_dev->dev;
31 pm->clock_gate = NULL;
32
33 /* clock control */
34 for (i = 0; i < pm->num_clocks; i++) {
35 pm->clocks[i] = devm_clk_get(pm->device, pm->clk_names[i]);
36 if (IS_ERR(pm->clocks[i])) {
37 /* additional clocks are optional */
38 if (i && PTR_ERR(pm->clocks[i]) == -ENOENT) {
39 pm->clocks[i] = NULL;
40 continue;
41 }
42 mfc_err("Failed to get clock: %s\n",
43 pm->clk_names[i]);
44 return PTR_ERR(pm->clocks[i]);
45 }
46 }
47
48 if (dev->variant->use_clock_gating)
49 pm->clock_gate = pm->clocks[0];
50
51 pm_runtime_enable(pm->device);
52 atomic_set(&clk_ref, 0);
53 return 0;
54 }
55
s5p_mfc_final_pm(struct s5p_mfc_dev * dev)56 void s5p_mfc_final_pm(struct s5p_mfc_dev *dev)
57 {
58 pm_runtime_disable(pm->device);
59 }
60
s5p_mfc_clock_on(void)61 int s5p_mfc_clock_on(void)
62 {
63 atomic_inc(&clk_ref);
64 mfc_debug(3, "+ %d\n", atomic_read(&clk_ref));
65
66 return clk_enable(pm->clock_gate);
67 }
68
s5p_mfc_clock_off(void)69 void s5p_mfc_clock_off(void)
70 {
71 atomic_dec(&clk_ref);
72 mfc_debug(3, "- %d\n", atomic_read(&clk_ref));
73
74 clk_disable(pm->clock_gate);
75 }
76
s5p_mfc_power_on(void)77 int s5p_mfc_power_on(void)
78 {
79 int i, ret = 0;
80
81 ret = pm_runtime_resume_and_get(pm->device);
82 if (ret < 0)
83 return ret;
84
85 /* clock control */
86 for (i = 0; i < pm->num_clocks; i++) {
87 ret = clk_prepare_enable(pm->clocks[i]);
88 if (ret < 0) {
89 mfc_err("clock prepare failed for clock: %s\n",
90 pm->clk_names[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