xref: /openbmc/u-boot/drivers/pwm/rk_pwm.c (revision 699e831e158a5846778d8bd6af054d4276277cb6)
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 struct rk_pwm_priv {
20 	struct rk3288_pwm *regs;
21 	ulong freq;
22 	uint enable_conf;
23 };
24 
25 static int rk_pwm_set_invert(struct udevice *dev, uint channel, bool polarity)
26 {
27 	struct rk_pwm_priv *priv = dev_get_priv(dev);
28 
29 	debug("%s: polarity=%u\n", __func__, polarity);
30 	priv->enable_conf &= ~(PWM_DUTY_MASK | PWM_INACTIVE_MASK);
31 	if (polarity)
32 		priv->enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSTIVE;
33 	else
34 		priv->enable_conf |= PWM_DUTY_POSTIVE | PWM_INACTIVE_NEGATIVE;
35 
36 	return 0;
37 }
38 
39 static int rk_pwm_set_config(struct udevice *dev, uint channel, uint period_ns,
40 			     uint duty_ns)
41 {
42 	struct rk_pwm_priv *priv = dev_get_priv(dev);
43 	struct rk3288_pwm *regs = priv->regs;
44 	unsigned long period, duty;
45 
46 	debug("%s: period_ns=%u, duty_ns=%u\n", __func__, period_ns, duty_ns);
47 	writel(PWM_SEL_SRC_CLK | PWM_OUTPUT_LEFT | PWM_LP_DISABLE |
48 		PWM_CONTINUOUS | priv->enable_conf |
49 		RK_PWM_DISABLE,
50 		&regs->ctrl);
51 
52 	period = lldiv((uint64_t)(priv->freq / 1000) * period_ns, 1000000);
53 	duty = lldiv((uint64_t)(priv->freq / 1000) * duty_ns, 1000000);
54 
55 	writel(period, &regs->period_hpr);
56 	writel(duty, &regs->duty_lpr);
57 	debug("%s: period=%lu, duty=%lu\n", __func__, period, duty);
58 
59 	return 0;
60 }
61 
62 static int rk_pwm_set_enable(struct udevice *dev, uint channel, bool enable)
63 {
64 	struct rk_pwm_priv *priv = dev_get_priv(dev);
65 	struct rk3288_pwm *regs = priv->regs;
66 
67 	debug("%s: Enable '%s'\n", __func__, dev->name);
68 	clrsetbits_le32(&regs->ctrl, RK_PWM_ENABLE, enable ? RK_PWM_ENABLE : 0);
69 
70 	return 0;
71 }
72 
73 static int rk_pwm_ofdata_to_platdata(struct udevice *dev)
74 {
75 	struct rk_pwm_priv *priv = dev_get_priv(dev);
76 
77 	priv->regs = (struct rk3288_pwm *)dev_read_addr(dev);
78 
79 	return 0;
80 }
81 
82 static int rk_pwm_probe(struct udevice *dev)
83 {
84 	struct rk_pwm_priv *priv = dev_get_priv(dev);
85 	struct clk clk;
86 	int ret = 0;
87 
88 	ret = clk_get_by_index(dev, 0, &clk);
89 	if (ret < 0) {
90 		debug("%s get clock fail!\n", __func__);
91 		return -EINVAL;
92 	}
93 	priv->freq = clk_get_rate(&clk);
94 	priv->enable_conf = PWM_DUTY_POSTIVE | PWM_INACTIVE_POSTIVE;
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