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7#include <linux/clk.h>
8#include <linux/io.h>
9#include <linux/module.h>
10#include <linux/of.h>
11#include <linux/platform_device.h>
12#include <linux/pwm.h>
13
14struct clps711x_chip {
15 struct pwm_chip chip;
16 void __iomem *pmpcon;
17 struct clk *clk;
18 spinlock_t lock;
19};
20
21static inline struct clps711x_chip *to_clps711x_chip(struct pwm_chip *chip)
22{
23 return container_of(chip, struct clps711x_chip, chip);
24}
25
26static void clps711x_pwm_update_val(struct clps711x_chip *priv, u32 n, u32 v)
27{
28
29 u32 shift = (n + 1) * 4;
30 unsigned long flags;
31 u32 tmp;
32
33 spin_lock_irqsave(&priv->lock, flags);
34
35 tmp = readl(priv->pmpcon);
36 tmp &= ~(0xf << shift);
37 tmp |= v << shift;
38 writel(tmp, priv->pmpcon);
39
40 spin_unlock_irqrestore(&priv->lock, flags);
41}
42
43static unsigned int clps711x_get_duty(struct pwm_device *pwm, unsigned int v)
44{
45
46 return DIV64_U64_ROUND_CLOSEST(v * 0xf, pwm->args.period);
47}
48
49static int clps711x_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
50{
51 struct clps711x_chip *priv = to_clps711x_chip(chip);
52 unsigned int freq = clk_get_rate(priv->clk);
53
54 if (!freq)
55 return -EINVAL;
56
57
58 pwm->args.period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, freq);
59
60 return 0;
61}
62
63static int clps711x_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
64 int duty_ns, int period_ns)
65{
66 struct clps711x_chip *priv = to_clps711x_chip(chip);
67 unsigned int duty;
68
69 if (period_ns != pwm->args.period)
70 return -EINVAL;
71
72 duty = clps711x_get_duty(pwm, duty_ns);
73 clps711x_pwm_update_val(priv, pwm->hwpwm, duty);
74
75 return 0;
76}
77
78static int clps711x_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
79{
80 struct clps711x_chip *priv = to_clps711x_chip(chip);
81 unsigned int duty;
82
83 duty = clps711x_get_duty(pwm, pwm_get_duty_cycle(pwm));
84 clps711x_pwm_update_val(priv, pwm->hwpwm, duty);
85
86 return 0;
87}
88
89static void clps711x_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
90{
91 struct clps711x_chip *priv = to_clps711x_chip(chip);
92
93 clps711x_pwm_update_val(priv, pwm->hwpwm, 0);
94}
95
96static const struct pwm_ops clps711x_pwm_ops = {
97 .request = clps711x_pwm_request,
98 .config = clps711x_pwm_config,
99 .enable = clps711x_pwm_enable,
100 .disable = clps711x_pwm_disable,
101 .owner = THIS_MODULE,
102};
103
104static struct pwm_device *clps711x_pwm_xlate(struct pwm_chip *chip,
105 const struct of_phandle_args *args)
106{
107 if (args->args[0] >= chip->npwm)
108 return ERR_PTR(-EINVAL);
109
110 return pwm_request_from_chip(chip, args->args[0], NULL);
111}
112
113static int clps711x_pwm_probe(struct platform_device *pdev)
114{
115 struct clps711x_chip *priv;
116
117 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
118 if (!priv)
119 return -ENOMEM;
120
121 priv->pmpcon = devm_platform_ioremap_resource(pdev, 0);
122 if (IS_ERR(priv->pmpcon))
123 return PTR_ERR(priv->pmpcon);
124
125 priv->clk = devm_clk_get(&pdev->dev, NULL);
126 if (IS_ERR(priv->clk))
127 return PTR_ERR(priv->clk);
128
129 priv->chip.ops = &clps711x_pwm_ops;
130 priv->chip.dev = &pdev->dev;
131 priv->chip.npwm = 2;
132 priv->chip.of_xlate = clps711x_pwm_xlate;
133 priv->chip.of_pwm_n_cells = 1;
134
135 spin_lock_init(&priv->lock);
136
137 return devm_pwmchip_add(&pdev->dev, &priv->chip);
138}
139
140static const struct of_device_id __maybe_unused clps711x_pwm_dt_ids[] = {
141 { .compatible = "cirrus,ep7209-pwm", },
142 { }
143};
144MODULE_DEVICE_TABLE(of, clps711x_pwm_dt_ids);
145
146static struct platform_driver clps711x_pwm_driver = {
147 .driver = {
148 .name = "clps711x-pwm",
149 .of_match_table = of_match_ptr(clps711x_pwm_dt_ids),
150 },
151 .probe = clps711x_pwm_probe,
152};
153module_platform_driver(clps711x_pwm_driver);
154
155MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
156MODULE_DESCRIPTION("Cirrus Logic CLPS711X PWM driver");
157MODULE_LICENSE("GPL");
158
