xref: /openbmc/u-boot/drivers/pwm/rk_pwm.c (revision e246b728)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2016 Google, Inc
4  * Written by Simon Glass <sjg@chromium.org>
5  */
6 
7 #include <common.h>
8 #include <clk.h>
9 #include <div64.h>
10 #include <dm.h>
11 #include <pwm.h>
12 #include <regmap.h>
13 #include <syscon.h>
14 #include <asm/io.h>
15 #include <asm/arch/pwm.h>
16 #include <power/regulator.h>
17 
18 struct rk_pwm_priv {
19 	struct rk3288_pwm *regs;
20 	ulong freq;
21 	uint enable_conf;
22 };
23 
24 static int rk_pwm_set_invert(struct udevice *dev, uint channel, bool polarity)
25 {
26 	struct rk_pwm_priv *priv = dev_get_priv(dev);
27 
28 	debug("%s: polarity=%u\n", __func__, polarity);
29 	priv->enable_conf &= ~(PWM_DUTY_MASK | PWM_INACTIVE_MASK);
30 	if (polarity)
31 		priv->enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSTIVE;
32 	else
33 		priv->enable_conf |= PWM_DUTY_POSTIVE | PWM_INACTIVE_NEGATIVE;
34 
35 	return 0;
36 }
37 
38 static int rk_pwm_set_config(struct udevice *dev, uint channel, uint period_ns,
39 			     uint duty_ns)
40 {
41 	struct rk_pwm_priv *priv = dev_get_priv(dev);
42 	struct rk3288_pwm *regs = priv->regs;
43 	unsigned long period, duty;
44 
45 	debug("%s: period_ns=%u, duty_ns=%u\n", __func__, period_ns, duty_ns);
46 	writel(PWM_SEL_SRC_CLK | PWM_OUTPUT_LEFT | PWM_LP_DISABLE |
47 		PWM_CONTINUOUS | priv->enable_conf |
48 		RK_PWM_DISABLE,
49 		&regs->ctrl);
50 
51 	period = lldiv((uint64_t)(priv->freq / 1000) * period_ns, 1000000);
52 	duty = lldiv((uint64_t)(priv->freq / 1000) * duty_ns, 1000000);
53 
54 	writel(period, &regs->period_hpr);
55 	writel(duty, &regs->duty_lpr);
56 	debug("%s: period=%lu, duty=%lu\n", __func__, period, duty);
57 
58 	return 0;
59 }
60 
61 static int rk_pwm_set_enable(struct udevice *dev, uint channel, bool enable)
62 {
63 	struct rk_pwm_priv *priv = dev_get_priv(dev);
64 	struct rk3288_pwm *regs = priv->regs;
65 
66 	debug("%s: Enable '%s'\n", __func__, dev->name);
67 	clrsetbits_le32(&regs->ctrl, RK_PWM_ENABLE, enable ? RK_PWM_ENABLE : 0);
68 
69 	return 0;
70 }
71 
72 static int rk_pwm_ofdata_to_platdata(struct udevice *dev)
73 {
74 	struct rk_pwm_priv *priv = dev_get_priv(dev);
75 
76 	priv->regs = (struct rk3288_pwm *)dev_read_addr(dev);
77 
78 	return 0;
79 }
80 
81 static int rk_pwm_probe(struct udevice *dev)
82 {
83 	struct rk_pwm_priv *priv = dev_get_priv(dev);
84 	struct clk clk;
85 	int ret = 0;
86 
87 	ret = clk_get_by_index(dev, 0, &clk);
88 	if (ret < 0) {
89 		debug("%s get clock fail!\n", __func__);
90 		return -EINVAL;
91 	}
92 	priv->freq = clk_get_rate(&clk);
93 	priv->enable_conf = PWM_DUTY_POSTIVE | PWM_INACTIVE_POSTIVE;
94 
95 	return 0;
96 }
97 
98 static const struct pwm_ops rk_pwm_ops = {
99 	.set_invert	= rk_pwm_set_invert,
100 	.set_config	= rk_pwm_set_config,
101 	.set_enable	= rk_pwm_set_enable,
102 };
103 
104 static const struct udevice_id rk_pwm_ids[] = {
105 	{ .compatible = "rockchip,rk3288-pwm" },
106 	{ }
107 };
108 
109 U_BOOT_DRIVER(rk_pwm) = {
110 	.name	= "rk_pwm",
111 	.id	= UCLASS_PWM,
112 	.of_match = rk_pwm_ids,
113 	.ops	= &rk_pwm_ops,
114 	.ofdata_to_platdata	= rk_pwm_ofdata_to_platdata,
115 	.probe		= rk_pwm_probe,
116 	.priv_auto_alloc_size	= sizeof(struct rk_pwm_priv),
117 };
118