1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * (C) Copyright 2014
4 * Heiko Schocher, DENX Software Engineering, hs@denx.de.
5 *
6 * Basic support for the pwm module on imx6.
7 */
8
9 #include <common.h>
10 #include <div64.h>
11 #include <dm.h>
12 #include <log.h>
13 #include <pwm.h>
14 #include <asm/arch/imx-regs.h>
15 #include <asm/io.h>
16 #include "pwm-imx-util.h"
17
pwm_init(int pwm_id,int div,int invert)18 int pwm_init(int pwm_id, int div, int invert)
19 {
20 struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
21
22 if (!pwm)
23 return -1;
24
25 writel(0, &pwm->ir);
26 return 0;
27 }
28
pwm_config_internal(struct pwm_regs * pwm,unsigned long period_cycles,unsigned long duty_cycles,unsigned long prescale)29 int pwm_config_internal(struct pwm_regs *pwm, unsigned long period_cycles,
30 unsigned long duty_cycles, unsigned long prescale)
31 {
32 u32 cr;
33
34 writel(0, &pwm->ir);
35 cr = PWMCR_PRESCALER(prescale) |
36 PWMCR_DOZEEN | PWMCR_WAITEN |
37 PWMCR_DBGEN | PWMCR_CLKSRC_IPG_HIGH;
38
39 writel(cr, &pwm->cr);
40 /* set duty cycles */
41 writel(duty_cycles, &pwm->sar);
42 /* set period cycles */
43 writel(period_cycles, &pwm->pr);
44 return 0;
45 }
46
pwm_config(int pwm_id,int duty_ns,int period_ns)47 int pwm_config(int pwm_id, int duty_ns, int period_ns)
48 {
49 struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
50 unsigned long period_cycles, duty_cycles, prescale;
51
52 if (!pwm)
53 return -1;
54
55 pwm_imx_get_parms(period_ns, duty_ns, &period_cycles, &duty_cycles,
56 &prescale);
57
58 return pwm_config_internal(pwm, period_cycles, duty_cycles, prescale);
59 }
60
pwm_enable(int pwm_id)61 int pwm_enable(int pwm_id)
62 {
63 struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
64
65 if (!pwm)
66 return -1;
67
68 setbits_le32(&pwm->cr, PWMCR_EN);
69 return 0;
70 }
71
pwm_disable(int pwm_id)72 void pwm_disable(int pwm_id)
73 {
74 struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
75
76 if (!pwm)
77 return;
78
79 clrbits_le32(&pwm->cr, PWMCR_EN);
80 }
81
82 #if defined(CONFIG_DM_PWM)
83 struct imx_pwm_priv {
84 struct pwm_regs *regs;
85 bool invert;
86 };
87
imx_pwm_set_invert(struct udevice * dev,uint channel,bool polarity)88 static int imx_pwm_set_invert(struct udevice *dev, uint channel,
89 bool polarity)
90 {
91 struct imx_pwm_priv *priv = dev_get_priv(dev);
92
93 debug("%s: polarity=%u\n", __func__, polarity);
94 priv->invert = polarity;
95
96 return 0;
97 }
98
imx_pwm_set_config(struct udevice * dev,uint channel,uint period_ns,uint duty_ns)99 static int imx_pwm_set_config(struct udevice *dev, uint channel,
100 uint period_ns, uint duty_ns)
101 {
102 struct imx_pwm_priv *priv = dev_get_priv(dev);
103 struct pwm_regs *regs = priv->regs;
104 unsigned long period_cycles, duty_cycles, prescale;
105
106 debug("%s: Config '%s' channel: %d\n", __func__, dev->name, channel);
107
108 pwm_imx_get_parms(period_ns, duty_ns, &period_cycles, &duty_cycles,
109 &prescale);
110
111 return pwm_config_internal(regs, period_cycles, duty_cycles, prescale);
112 };
113
imx_pwm_set_enable(struct udevice * dev,uint channel,bool enable)114 static int imx_pwm_set_enable(struct udevice *dev, uint channel, bool enable)
115 {
116 struct imx_pwm_priv *priv = dev_get_priv(dev);
117 struct pwm_regs *regs = priv->regs;
118
119 debug("%s: Enable '%s' state: %d\n", __func__, dev->name, enable);
120
121 if (enable)
122 setbits_le32(®s->cr, PWMCR_EN);
123 else
124 clrbits_le32(®s->cr, PWMCR_EN);
125
126 return 0;
127 };
128
imx_pwm_of_to_plat(struct udevice * dev)129 static int imx_pwm_of_to_plat(struct udevice *dev)
130 {
131 struct imx_pwm_priv *priv = dev_get_priv(dev);
132
133 priv->regs = dev_read_addr_ptr(dev);
134
135 return 0;
136 }
137
imx_pwm_probe(struct udevice * dev)138 static int imx_pwm_probe(struct udevice *dev)
139 {
140 return 0;
141 }
142
143 static const struct pwm_ops imx_pwm_ops = {
144 .set_invert = imx_pwm_set_invert,
145 .set_config = imx_pwm_set_config,
146 .set_enable = imx_pwm_set_enable,
147 };
148
149 static const struct udevice_id imx_pwm_ids[] = {
150 { .compatible = "fsl,imx27-pwm" },
151 { }
152 };
153
154 U_BOOT_DRIVER(imx_pwm) = {
155 .name = "imx_pwm",
156 .id = UCLASS_PWM,
157 .of_match = imx_pwm_ids,
158 .ops = &imx_pwm_ops,
159 .of_to_plat = imx_pwm_of_to_plat,
160 .probe = imx_pwm_probe,
161 .priv_auto = sizeof(struct imx_pwm_priv),
162 };
163 #endif
164