xref: /openbmc/u-boot/drivers/pwm/rk_pwm.c (revision 2a728f3a)
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 	priv->enable_conf &= ~(PWM_DUTY_MASK | PWM_INACTIVE_MASK);
33 	if (polarity)
34 		priv->enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSTIVE;
35 	else
36 		priv->enable_conf |= PWM_DUTY_POSTIVE | PWM_INACTIVE_NEGATIVE;
37 
38 	return 0;
39 }
40 
41 static int rk_pwm_set_config(struct udevice *dev, uint channel, uint period_ns,
42 			     uint duty_ns)
43 {
44 	struct rk_pwm_priv *priv = dev_get_priv(dev);
45 	struct rk3288_pwm *regs = priv->regs;
46 	unsigned long period, duty;
47 
48 	debug("%s: period_ns=%u, duty_ns=%u\n", __func__, period_ns, duty_ns);
49 	writel(PWM_SEL_SRC_CLK | PWM_OUTPUT_LEFT | PWM_LP_DISABLE |
50 		PWM_CONTINUOUS | priv->enable_conf |
51 		RK_PWM_DISABLE,
52 		&regs->ctrl);
53 
54 	period = lldiv((uint64_t)(priv->freq / 1000) * period_ns, 1000000);
55 	duty = lldiv((uint64_t)(priv->freq / 1000) * duty_ns, 1000000);
56 
57 	writel(period, &regs->period_hpr);
58 	writel(duty, &regs->duty_lpr);
59 	debug("%s: period=%lu, duty=%lu\n", __func__, period, duty);
60 
61 	return 0;
62 }
63 
64 static int rk_pwm_set_enable(struct udevice *dev, uint channel, bool enable)
65 {
66 	struct rk_pwm_priv *priv = dev_get_priv(dev);
67 	struct rk3288_pwm *regs = priv->regs;
68 
69 	debug("%s: Enable '%s'\n", __func__, dev->name);
70 	clrsetbits_le32(&regs->ctrl, RK_PWM_ENABLE, enable ? RK_PWM_ENABLE : 0);
71 
72 	return 0;
73 }
74 
75 static int rk_pwm_ofdata_to_platdata(struct udevice *dev)
76 {
77 	struct rk_pwm_priv *priv = dev_get_priv(dev);
78 
79 	priv->regs = (struct rk3288_pwm *)devfdt_get_addr(dev);
80 
81 	return 0;
82 }
83 
84 static int rk_pwm_probe(struct udevice *dev)
85 {
86 	struct rk_pwm_priv *priv = dev_get_priv(dev);
87 	struct clk clk;
88 	int ret = 0;
89 
90 	ret = clk_get_by_index(dev, 0, &clk);
91 	if (ret < 0) {
92 		debug("%s get clock fail!\n", __func__);
93 		return -EINVAL;
94 	}
95 	priv->freq = clk_get_rate(&clk);
96 	priv->enable_conf = PWM_DUTY_POSTIVE | PWM_INACTIVE_POSTIVE;
97 
98 	return 0;
99 }
100 
101 static const struct pwm_ops rk_pwm_ops = {
102 	.set_invert	= rk_pwm_set_invert,
103 	.set_config	= rk_pwm_set_config,
104 	.set_enable	= rk_pwm_set_enable,
105 };
106 
107 static const struct udevice_id rk_pwm_ids[] = {
108 	{ .compatible = "rockchip,rk3288-pwm" },
109 	{ }
110 };
111 
112 U_BOOT_DRIVER(rk_pwm) = {
113 	.name	= "rk_pwm",
114 	.id	= UCLASS_PWM,
115 	.of_match = rk_pwm_ids,
116 	.ops	= &rk_pwm_ops,
117 	.ofdata_to_platdata	= rk_pwm_ofdata_to_platdata,
118 	.probe		= rk_pwm_probe,
119 	.priv_auto_alloc_size	= sizeof(struct rk_pwm_priv),
120 };
121