xref: /openbmc/u-boot/drivers/pwm/rk_pwm.c (revision 028d6849)
1 /*
2  * Copyright (c) 2016 Google, Inc
3  * Written by Simon Glass <sjg@chromium.org>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <clk.h>
10 #include <div64.h>
11 #include <dm.h>
12 #include <pwm.h>
13 #include <regmap.h>
14 #include <syscon.h>
15 #include <asm/io.h>
16 #include <asm/arch/pwm.h>
17 #include <power/regulator.h>
18 
19 DECLARE_GLOBAL_DATA_PTR;
20 
21 struct rk_pwm_priv {
22 	struct rk3288_pwm *regs;
23 	ulong freq;
24 	uint enable_conf;
25 };
26 
27 static int rk_pwm_set_invert(struct udevice *dev, uint channel, bool polarity)
28 {
29 	struct rk_pwm_priv *priv = dev_get_priv(dev);
30 
31 	debug("%s: polarity=%u\n", __func__, polarity);
32 	if (polarity)
33 		priv->enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSTIVE;
34 	else
35 		priv->enable_conf |= PWM_DUTY_POSTIVE | PWM_INACTIVE_NEGATIVE;
36 
37 	return 0;
38 }
39 
40 static int rk_pwm_set_config(struct udevice *dev, uint channel, uint period_ns,
41 			     uint duty_ns)
42 {
43 	struct rk_pwm_priv *priv = dev_get_priv(dev);
44 	struct rk3288_pwm *regs = priv->regs;
45 	unsigned long period, duty;
46 
47 	debug("%s: period_ns=%u, duty_ns=%u\n", __func__, period_ns, duty_ns);
48 	writel(PWM_SEL_SRC_CLK | PWM_OUTPUT_LEFT | PWM_LP_DISABLE |
49 		PWM_CONTINUOUS | priv->enable_conf |
50 		RK_PWM_DISABLE,
51 		&regs->ctrl);
52 
53 	period = lldiv((uint64_t)(priv->freq / 1000) * period_ns, 1000000);
54 	duty = lldiv((uint64_t)(priv->freq / 1000) * duty_ns, 1000000);
55 
56 	writel(period, &regs->period_hpr);
57 	writel(duty, &regs->duty_lpr);
58 	debug("%s: period=%lu, duty=%lu\n", __func__, period, duty);
59 
60 	return 0;
61 }
62 
63 static int rk_pwm_set_enable(struct udevice *dev, uint channel, bool enable)
64 {
65 	struct rk_pwm_priv *priv = dev_get_priv(dev);
66 	struct rk3288_pwm *regs = priv->regs;
67 
68 	debug("%s: Enable '%s'\n", __func__, dev->name);
69 	clrsetbits_le32(&regs->ctrl, RK_PWM_ENABLE, enable ? RK_PWM_ENABLE : 0);
70 
71 	return 0;
72 }
73 
74 static int rk_pwm_ofdata_to_platdata(struct udevice *dev)
75 {
76 	struct rk_pwm_priv *priv = dev_get_priv(dev);
77 
78 	priv->regs = (struct rk3288_pwm *)dev_get_addr(dev);
79 
80 	return 0;
81 }
82 
83 static int rk_pwm_probe(struct udevice *dev)
84 {
85 	struct rk_pwm_priv *priv = dev_get_priv(dev);
86 	struct clk clk;
87 	int ret = 0;
88 
89 	ret = clk_get_by_index(dev, 0, &clk);
90 	if (ret < 0) {
91 		debug("%s get clock fail!\n", __func__);
92 		return -EINVAL;
93 	}
94 	priv->freq = clk_get_rate(&clk);
95 
96 	return 0;
97 }
98 
99 static const struct pwm_ops rk_pwm_ops = {
100 	.set_invert	= rk_pwm_set_invert,
101 	.set_config	= rk_pwm_set_config,
102 	.set_enable	= rk_pwm_set_enable,
103 };
104 
105 static const struct udevice_id rk_pwm_ids[] = {
106 	{ .compatible = "rockchip,rk3288-pwm" },
107 	{ }
108 };
109 
110 U_BOOT_DRIVER(rk_pwm) = {
111 	.name	= "rk_pwm",
112 	.id	= UCLASS_PWM,
113 	.of_match = rk_pwm_ids,
114 	.ops	= &rk_pwm_ops,
115 	.ofdata_to_platdata	= rk_pwm_ofdata_to_platdata,
116 	.probe		= rk_pwm_probe,
117 	.priv_auto_alloc_size	= sizeof(struct rk_pwm_priv),
118 };
119