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authorOlof Johansson <olof@lixom.net>2012-03-08 11:53:14 -0500
committerOlof Johansson <olof@lixom.net>2012-03-08 11:53:14 -0500
commitd60d506e6baaf423148c458df3ece0c1d440dce4 (patch)
treec25c44e70ebaaddcbe39559df5c5cd260e956be4 /arch/arm/mach-s3c24xx/mach-osiris-dvs.c
parent62f383435932ea3d271bee6b957de048452c1b16 (diff)
parent2e5ac9436645bb9fd2097868e228321f303c9c75 (diff)
Merge branch 'next/cleanup-s3c24xx' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into next/cleanup
* 'next/cleanup-s3c24xx' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung: (24 commits) ARM: S3C24XX: remove call to s3c24xx_setup_clocks ARM: S3C24XX: add get_rate for clk_p on S3C2416/2443 ARM: S3C24XX: add get_rate for clk_h on S3C2416/2443 ARM: S3C24XX: remove XXX_setup_clocks method from S3C2443 ARM: S3C24XX: remove obsolete S3C2416_DMA option ARM: S3C24XX: Reuse S3C2443 dma for S3C2416 ARM: S3C24XX: Fix indentation of dma-s3c2443 ARM: S3C24XX: Move device setup files to mach directory ARM: S3C24XX: Consolidate Simtec extensions ARM: S3C24XX: move simtec-specific code to mach directory ARM: S3C24XX: Move common-smdk code to mach directory ARM: S3C24XX: Move s3c2443-clock.c to mach-s3c24xx ARM: s3c2410_defconfig: update s3c2410_defconfig ARM: S3C2443: move mach-s3c2443/* into mach-s3c24xx/ ARM: S3C2440: move mach-s3c2440/* into mach-s3c24xx/ ARM: S3C2416: move mach-s3c2416/* into mach-s3c24xx/ ARM: S3C2412: move mach-s3c2412/* into mach-s3c24xx/ ARM: S3C2410: move mach-s3c2410/* into mach-s3c24xx/ ARM: S3C24XX: change the ARCH_S3C2410 to ARCH_S3C24XX ARM: S3C2410: move s3c2410_baseclk_add to clock.h ...
Diffstat (limited to 'arch/arm/mach-s3c24xx/mach-osiris-dvs.c')
-rw-r--r--arch/arm/mach-s3c24xx/mach-osiris-dvs.c194
1 files changed, 194 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c24xx/mach-osiris-dvs.c b/arch/arm/mach-s3c24xx/mach-osiris-dvs.c
new file mode 100644
index 000000000000..ad2792dfbee1
--- /dev/null
+++ b/arch/arm/mach-s3c24xx/mach-osiris-dvs.c
@@ -0,0 +1,194 @@
1/* linux/arch/arm/mach-s3c2440/mach-osiris-dvs.c
2 *
3 * Copyright (c) 2009 Simtec Electronics
4 * http://armlinux.simtec.co.uk/
5 * Ben Dooks <ben@simtec.co.uk>
6 *
7 * Simtec Osiris Dynamic Voltage Scaling support.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
12*/
13
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/platform_device.h>
17#include <linux/cpufreq.h>
18#include <linux/gpio.h>
19
20#include <linux/i2c/tps65010.h>
21
22#include <plat/cpu-freq.h>
23
24#define OSIRIS_GPIO_DVS S3C2410_GPB(5)
25
26static bool dvs_en;
27
28static void osiris_dvs_tps_setdvs(bool on)
29{
30 unsigned vregs1 = 0, vdcdc2 = 0;
31
32 if (!on) {
33 vdcdc2 = TPS_VCORE_DISCH | TPS_LP_COREOFF;
34 vregs1 = TPS_LDO1_OFF; /* turn off in low-power mode */
35 }
36
37 dvs_en = on;
38 vdcdc2 |= TPS_VCORE_1_3V | TPS_VCORE_LP_1_0V;
39 vregs1 |= TPS_LDO2_ENABLE | TPS_LDO1_ENABLE;
40
41 tps65010_config_vregs1(vregs1);
42 tps65010_config_vdcdc2(vdcdc2);
43}
44
45static bool is_dvs(struct s3c_freq *f)
46{
47 /* at the moment, we assume ARMCLK = HCLK => DVS */
48 return f->armclk == f->hclk;
49}
50
51/* keep track of current state */
52static bool cur_dvs = false;
53
54static int osiris_dvs_notify(struct notifier_block *nb,
55 unsigned long val, void *data)
56{
57 struct cpufreq_freqs *cf = data;
58 struct s3c_cpufreq_freqs *freqs = to_s3c_cpufreq(cf);
59 bool old_dvs = is_dvs(&freqs->old);
60 bool new_dvs = is_dvs(&freqs->new);
61 int ret = 0;
62
63 if (!dvs_en)
64 return 0;
65
66 printk(KERN_DEBUG "%s: old %ld,%ld new %ld,%ld\n", __func__,
67 freqs->old.armclk, freqs->old.hclk,
68 freqs->new.armclk, freqs->new.hclk);
69
70 switch (val) {
71 case CPUFREQ_PRECHANGE:
72 if (old_dvs & !new_dvs ||
73 cur_dvs & !new_dvs) {
74 pr_debug("%s: exiting dvs\n", __func__);
75 cur_dvs = false;
76 gpio_set_value(OSIRIS_GPIO_DVS, 1);
77 }
78 break;
79 case CPUFREQ_POSTCHANGE:
80 if (!old_dvs & new_dvs ||
81 !cur_dvs & new_dvs) {
82 pr_debug("entering dvs\n");
83 cur_dvs = true;
84 gpio_set_value(OSIRIS_GPIO_DVS, 0);
85 }
86 break;
87 }
88
89 return ret;
90}
91
92static struct notifier_block osiris_dvs_nb = {
93 .notifier_call = osiris_dvs_notify,
94};
95
96static int __devinit osiris_dvs_probe(struct platform_device *pdev)
97{
98 int ret;
99
100 dev_info(&pdev->dev, "initialising\n");
101
102 ret = gpio_request(OSIRIS_GPIO_DVS, "osiris-dvs");
103 if (ret) {
104 dev_err(&pdev->dev, "cannot claim gpio\n");
105 goto err_nogpio;
106 }
107
108 /* start with dvs disabled */
109 gpio_direction_output(OSIRIS_GPIO_DVS, 1);
110
111 ret = cpufreq_register_notifier(&osiris_dvs_nb,
112 CPUFREQ_TRANSITION_NOTIFIER);
113 if (ret) {
114 dev_err(&pdev->dev, "failed to register with cpufreq\n");
115 goto err_nofreq;
116 }
117
118 osiris_dvs_tps_setdvs(true);
119
120 return 0;
121
122err_nofreq:
123 gpio_free(OSIRIS_GPIO_DVS);
124
125err_nogpio:
126 return ret;
127}
128
129static int __devexit osiris_dvs_remove(struct platform_device *pdev)
130{
131 dev_info(&pdev->dev, "exiting\n");
132
133 /* disable any current dvs */
134 gpio_set_value(OSIRIS_GPIO_DVS, 1);
135 osiris_dvs_tps_setdvs(false);
136
137 cpufreq_unregister_notifier(&osiris_dvs_nb,
138 CPUFREQ_TRANSITION_NOTIFIER);
139
140 gpio_free(OSIRIS_GPIO_DVS);
141
142 return 0;
143}
144
145/* the CONFIG_PM block is so small, it isn't worth actaully compiling it
146 * out if the configuration isn't set. */
147
148static int osiris_dvs_suspend(struct device *dev)
149{
150 gpio_set_value(OSIRIS_GPIO_DVS, 1);
151 osiris_dvs_tps_setdvs(false);
152 cur_dvs = false;
153
154 return 0;
155}
156
157static int osiris_dvs_resume(struct device *dev)
158{
159 osiris_dvs_tps_setdvs(true);
160 return 0;
161}
162
163static const struct dev_pm_ops osiris_dvs_pm = {
164 .suspend = osiris_dvs_suspend,
165 .resume = osiris_dvs_resume,
166};
167
168static struct platform_driver osiris_dvs_driver = {
169 .probe = osiris_dvs_probe,
170 .remove = __devexit_p(osiris_dvs_remove),
171 .driver = {
172 .name = "osiris-dvs",
173 .owner = THIS_MODULE,
174 .pm = &osiris_dvs_pm,
175 },
176};
177
178static int __init osiris_dvs_init(void)
179{
180 return platform_driver_register(&osiris_dvs_driver);
181}
182
183static void __exit osiris_dvs_exit(void)
184{
185 platform_driver_unregister(&osiris_dvs_driver);
186}
187
188module_init(osiris_dvs_init);
189module_exit(osiris_dvs_exit);
190
191MODULE_DESCRIPTION("Simtec OSIRIS DVS support");
192MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
193MODULE_LICENSE("GPL");
194MODULE_ALIAS("platform:osiris-dvs");