xref: /openbmc/u-boot/drivers/pwm/rk_pwm.c (revision e9c847c3)
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 };
25 
26 static int rk_pwm_set_config(struct udevice *dev, uint channel, uint period_ns,
27 			     uint duty_ns)
28 {
29 	struct rk_pwm_priv *priv = dev_get_priv(dev);
30 	struct rk3288_pwm *regs = priv->regs;
31 	unsigned long period, duty;
32 
33 	debug("%s: period_ns=%u, duty_ns=%u\n", __func__, period_ns, duty_ns);
34 	writel(PWM_SEL_SRC_CLK | PWM_OUTPUT_LEFT | PWM_LP_DISABLE |
35 		PWM_CONTINUOUS | PWM_DUTY_POSTIVE | PWM_INACTIVE_POSTIVE |
36 		RK_PWM_DISABLE,
37 		&regs->ctrl);
38 
39 	period = lldiv((uint64_t)(priv->freq / 1000) * period_ns, 1000000);
40 	duty = lldiv((uint64_t)(priv->freq / 1000) * duty_ns, 1000000);
41 
42 	writel(period, &regs->period_hpr);
43 	writel(duty, &regs->duty_lpr);
44 	debug("%s: period=%lu, duty=%lu\n", __func__, period, duty);
45 
46 	return 0;
47 }
48 
49 static int rk_pwm_set_enable(struct udevice *dev, uint channel, bool enable)
50 {
51 	struct rk_pwm_priv *priv = dev_get_priv(dev);
52 	struct rk3288_pwm *regs = priv->regs;
53 
54 	debug("%s: Enable '%s'\n", __func__, dev->name);
55 	clrsetbits_le32(&regs->ctrl, RK_PWM_ENABLE, enable ? RK_PWM_ENABLE : 0);
56 
57 	return 0;
58 }
59 
60 static int rk_pwm_ofdata_to_platdata(struct udevice *dev)
61 {
62 	struct rk_pwm_priv *priv = dev_get_priv(dev);
63 
64 	priv->regs = (struct rk3288_pwm *)dev_get_addr(dev);
65 
66 	return 0;
67 }
68 
69 static int rk_pwm_probe(struct udevice *dev)
70 {
71 	struct rk_pwm_priv *priv = dev_get_priv(dev);
72 	struct clk clk;
73 	int ret = 0;
74 
75 	ret = clk_get_by_index(dev, 0, &clk);
76 	if (ret < 0) {
77 		debug("%s get clock fail!\n", __func__);
78 		return -EINVAL;
79 	}
80 	priv->freq = clk_get_rate(&clk);
81 
82 	return 0;
83 }
84 
85 static const struct pwm_ops rk_pwm_ops = {
86 	.set_config	= rk_pwm_set_config,
87 	.set_enable	= rk_pwm_set_enable,
88 };
89 
90 static const struct udevice_id rk_pwm_ids[] = {
91 	{ .compatible = "rockchip,rk3288-pwm" },
92 	{ }
93 };
94 
95 U_BOOT_DRIVER(rk_pwm) = {
96 	.name	= "rk_pwm",
97 	.id	= UCLASS_PWM,
98 	.of_match = rk_pwm_ids,
99 	.ops	= &rk_pwm_ops,
100 	.ofdata_to_platdata	= rk_pwm_ofdata_to_platdata,
101 	.probe		= rk_pwm_probe,
102 	.priv_auto_alloc_size	= sizeof(struct rk_pwm_priv),
103 };
104