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1/*
2 * Copyright (C) ST-Ericsson SA 2010
3 *
4 * Author: Arun R Murthy <arun.murthy@stericsson.com>
5 * License terms: GNU General Public License (GPL) version 2
6 */
7#include <linux/err.h>
8#include <linux/platform_device.h>
9#include <linux/slab.h>
10#include <linux/pwm.h>
11#include <linux/mfd/ab8500.h>
12#include <linux/mfd/abx500.h>
13
14/*
15 * PWM Out generators
16 * Bank: 0x10
17 */
18#define AB8500_PWM_OUT_CTRL1_REG 0x60
19#define AB8500_PWM_OUT_CTRL2_REG 0x61
20#define AB8500_PWM_OUT_CTRL7_REG 0x66
21
22/* backlight driver constants */
23#define ENABLE_PWM 1
24#define DISABLE_PWM 0
25
26struct pwm_device {
27 struct device *dev;
28 struct list_head node;
29 const char *label;
30 unsigned int pwm_id;
31};
32
33static LIST_HEAD(pwm_list);
34
35int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
36{
37 int ret = 0;
38 unsigned int higher_val, lower_val;
39 u8 reg;
40
41 /*
42 * get the first 8 bits that are be written to
43 * AB8500_PWM_OUT_CTRL1_REG[0:7]
44 */
45 lower_val = duty_ns & 0x00FF;
46 /*
47 * get bits [9:10] that are to be written to
48 * AB8500_PWM_OUT_CTRL2_REG[0:1]
49 */
50 higher_val = ((duty_ns & 0x0300) >> 8);
51
52 reg = AB8500_PWM_OUT_CTRL1_REG + ((pwm->pwm_id - 1) * 2);
53
54 ret = abx500_set_register_interruptible(pwm->dev, AB8500_MISC,
55 reg, (u8)lower_val);
56 if (ret < 0)
57 return ret;
58 ret = abx500_set_register_interruptible(pwm->dev, AB8500_MISC,
59 (reg + 1), (u8)higher_val);
60
61 return ret;
62}
63EXPORT_SYMBOL(pwm_config);
64
65int pwm_enable(struct pwm_device *pwm)
66{
67 int ret;
68
69 ret = abx500_mask_and_set_register_interruptible(pwm->dev,
70 AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
71 1 << (pwm->pwm_id-1), ENABLE_PWM);
72 if (ret < 0)
73 dev_err(pwm->dev, "%s: Failed to disable PWM, Error %d\n",
74 pwm->label, ret);
75 return ret;
76}
77EXPORT_SYMBOL(pwm_enable);
78
79void pwm_disable(struct pwm_device *pwm)
80{
81 int ret;
82
83 ret = abx500_mask_and_set_register_interruptible(pwm->dev,
84 AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
85 1 << (pwm->pwm_id-1), DISABLE_PWM);
86 if (ret < 0)
87 dev_err(pwm->dev, "%s: Failed to disable PWM, Error %d\n",
88 pwm->label, ret);
89 return;
90}
91EXPORT_SYMBOL(pwm_disable);
92
93struct pwm_device *pwm_request(int pwm_id, const char *label)
94{
95 struct pwm_device *pwm;
96
97 list_for_each_entry(pwm, &pwm_list, node) {
98 if (pwm->pwm_id == pwm_id) {
99 pwm->label = label;
100 pwm->pwm_id = pwm_id;
101 return pwm;
102 }
103 }
104
105 return ERR_PTR(-ENOENT);
106}
107EXPORT_SYMBOL(pwm_request);
108
109void pwm_free(struct pwm_device *pwm)
110{
111 pwm_disable(pwm);
112}
113EXPORT_SYMBOL(pwm_free);
114
115static int __devinit ab8500_pwm_probe(struct platform_device *pdev)
116{
117 struct pwm_device *pwm;
118 /*
119 * Nothing to be done in probe, this is required to get the
120 * device which is required for ab8500 read and write
121 */
122 pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
123 if (pwm == NULL) {
124 dev_err(&pdev->dev, "failed to allocate memory\n");
125 return -ENOMEM;
126 }
127 pwm->dev = &pdev->dev;
128 pwm->pwm_id = pdev->id;
129 list_add_tail(&pwm->node, &pwm_list);
130 platform_set_drvdata(pdev, pwm);
131 dev_dbg(pwm->dev, "pwm probe successful\n");
132 return 0;
133}
134
135static int __devexit ab8500_pwm_remove(struct platform_device *pdev)
136{
137 struct pwm_device *pwm = platform_get_drvdata(pdev);
138 list_del(&pwm->node);
139 dev_dbg(&pdev->dev, "pwm driver removed\n");
140 kfree(pwm);
141 return 0;
142}
143
144static struct platform_driver ab8500_pwm_driver = {
145 .driver = {
146 .name = "ab8500-pwm",
147 .owner = THIS_MODULE,
148 },
149 .probe = ab8500_pwm_probe,
150 .remove = __devexit_p(ab8500_pwm_remove),
151};
152
153static int __init ab8500_pwm_init(void)
154{
155 return platform_driver_register(&ab8500_pwm_driver);
156}
157
158static void __exit ab8500_pwm_exit(void)
159{
160 platform_driver_unregister(&ab8500_pwm_driver);
161}
162
163subsys_initcall(ab8500_pwm_init);
164module_exit(ab8500_pwm_exit);
165MODULE_AUTHOR("Arun MURTHY <arun.murthy@stericsson.com>");
166MODULE_DESCRIPTION("AB8500 Pulse Width Modulation Driver");
167MODULE_ALIAS("platform:ab8500-pwm");
168MODULE_LICENSE("GPL v2");
1/*
2 * Copyright (C) ST-Ericsson SA 2010
3 *
4 * Author: Arun R Murthy <arun.murthy@stericsson.com>
5 * License terms: GNU General Public License (GPL) version 2
6 */
7#include <linux/err.h>
8#include <linux/platform_device.h>
9#include <linux/slab.h>
10#include <linux/pwm.h>
11#include <linux/mfd/abx500.h>
12#include <linux/mfd/abx500/ab8500.h>
13#include <linux/module.h>
14
15/*
16 * PWM Out generators
17 * Bank: 0x10
18 */
19#define AB8500_PWM_OUT_CTRL1_REG 0x60
20#define AB8500_PWM_OUT_CTRL2_REG 0x61
21#define AB8500_PWM_OUT_CTRL7_REG 0x66
22
23/* backlight driver constants */
24#define ENABLE_PWM 1
25#define DISABLE_PWM 0
26
27struct pwm_device {
28 struct device *dev;
29 struct list_head node;
30 const char *label;
31 unsigned int pwm_id;
32};
33
34static LIST_HEAD(pwm_list);
35
36int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
37{
38 int ret = 0;
39 unsigned int higher_val, lower_val;
40 u8 reg;
41
42 /*
43 * get the first 8 bits that are be written to
44 * AB8500_PWM_OUT_CTRL1_REG[0:7]
45 */
46 lower_val = duty_ns & 0x00FF;
47 /*
48 * get bits [9:10] that are to be written to
49 * AB8500_PWM_OUT_CTRL2_REG[0:1]
50 */
51 higher_val = ((duty_ns & 0x0300) >> 8);
52
53 reg = AB8500_PWM_OUT_CTRL1_REG + ((pwm->pwm_id - 1) * 2);
54
55 ret = abx500_set_register_interruptible(pwm->dev, AB8500_MISC,
56 reg, (u8)lower_val);
57 if (ret < 0)
58 return ret;
59 ret = abx500_set_register_interruptible(pwm->dev, AB8500_MISC,
60 (reg + 1), (u8)higher_val);
61
62 return ret;
63}
64EXPORT_SYMBOL(pwm_config);
65
66int pwm_enable(struct pwm_device *pwm)
67{
68 int ret;
69
70 ret = abx500_mask_and_set_register_interruptible(pwm->dev,
71 AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
72 1 << (pwm->pwm_id-1), ENABLE_PWM);
73 if (ret < 0)
74 dev_err(pwm->dev, "%s: Failed to disable PWM, Error %d\n",
75 pwm->label, ret);
76 return ret;
77}
78EXPORT_SYMBOL(pwm_enable);
79
80void pwm_disable(struct pwm_device *pwm)
81{
82 int ret;
83
84 ret = abx500_mask_and_set_register_interruptible(pwm->dev,
85 AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
86 1 << (pwm->pwm_id-1), DISABLE_PWM);
87 if (ret < 0)
88 dev_err(pwm->dev, "%s: Failed to disable PWM, Error %d\n",
89 pwm->label, ret);
90 return;
91}
92EXPORT_SYMBOL(pwm_disable);
93
94struct pwm_device *pwm_request(int pwm_id, const char *label)
95{
96 struct pwm_device *pwm;
97
98 list_for_each_entry(pwm, &pwm_list, node) {
99 if (pwm->pwm_id == pwm_id) {
100 pwm->label = label;
101 pwm->pwm_id = pwm_id;
102 return pwm;
103 }
104 }
105
106 return ERR_PTR(-ENOENT);
107}
108EXPORT_SYMBOL(pwm_request);
109
110void pwm_free(struct pwm_device *pwm)
111{
112 pwm_disable(pwm);
113}
114EXPORT_SYMBOL(pwm_free);
115
116static int __devinit ab8500_pwm_probe(struct platform_device *pdev)
117{
118 struct pwm_device *pwm;
119 /*
120 * Nothing to be done in probe, this is required to get the
121 * device which is required for ab8500 read and write
122 */
123 pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
124 if (pwm == NULL) {
125 dev_err(&pdev->dev, "failed to allocate memory\n");
126 return -ENOMEM;
127 }
128 pwm->dev = &pdev->dev;
129 pwm->pwm_id = pdev->id;
130 list_add_tail(&pwm->node, &pwm_list);
131 platform_set_drvdata(pdev, pwm);
132 dev_dbg(pwm->dev, "pwm probe successful\n");
133 return 0;
134}
135
136static int __devexit ab8500_pwm_remove(struct platform_device *pdev)
137{
138 struct pwm_device *pwm = platform_get_drvdata(pdev);
139 list_del(&pwm->node);
140 dev_dbg(&pdev->dev, "pwm driver removed\n");
141 kfree(pwm);
142 return 0;
143}
144
145static const struct of_device_id ab8500_pwm_match[] = {
146 { .compatible = "stericsson,ab8500-pwm", },
147 {}
148};
149
150static struct platform_driver ab8500_pwm_driver = {
151 .driver = {
152 .name = "ab8500-pwm",
153 .owner = THIS_MODULE,
154 .of_match_table = ab8500_pwm_match,
155 },
156 .probe = ab8500_pwm_probe,
157 .remove = __devexit_p(ab8500_pwm_remove),
158};
159
160static int __init ab8500_pwm_init(void)
161{
162 return platform_driver_register(&ab8500_pwm_driver);
163}
164
165static void __exit ab8500_pwm_exit(void)
166{
167 platform_driver_unregister(&ab8500_pwm_driver);
168}
169
170subsys_initcall(ab8500_pwm_init);
171module_exit(ab8500_pwm_exit);
172MODULE_AUTHOR("Arun MURTHY <arun.murthy@stericsson.com>");
173MODULE_DESCRIPTION("AB8500 Pulse Width Modulation Driver");
174MODULE_ALIAS("platform:ab8500-pwm");
175MODULE_LICENSE("GPL v2");