1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (c) 2015 Google, Inc
4 * Written by Simon Glass <sjg@chromium.org>
5 */
6
7 #include <common.h>
8 #include <dm.h>
9 #include <errno.h>
10 #include <pwm.h>
11 #include <asm/test.h>
12
13 enum {
14 NUM_CHANNELS = 3,
15 };
16
17 /**
18 * struct sandbox_pwm_chan - a sandbox PWM channel
19 *
20 * @period_ns: Period of the PWM in nanoseconds
21 * @duty_ns: Current duty cycle of the PWM in nanoseconds
22 * @enable: true if the PWM is enabled
23 * @polarity: true if the PWM polarity is active high
24 */
25 struct sandbox_pwm_chan {
26 uint period_ns;
27 uint duty_ns;
28 bool enable;
29 bool polarity;
30 };
31
32 struct sandbox_pwm_priv {
33 struct sandbox_pwm_chan chan[NUM_CHANNELS];
34 };
35
sandbox_pwm_get_config(struct udevice * dev,uint channel,uint * period_nsp,uint * duty_nsp,bool * enablep,bool * polarityp)36 int sandbox_pwm_get_config(struct udevice *dev, uint channel, uint *period_nsp,
37 uint *duty_nsp, bool *enablep, bool *polarityp)
38 {
39 struct sandbox_pwm_priv *priv = dev_get_priv(dev);
40 struct sandbox_pwm_chan *chan;
41
42 if (channel >= NUM_CHANNELS)
43 return -ENOSPC;
44 chan = &priv->chan[channel];
45 *period_nsp = chan->period_ns;
46 *duty_nsp = chan->duty_ns;
47 *enablep = chan->enable;
48 *polarityp = chan->polarity;
49
50 return 0;
51 }
52
sandbox_pwm_set_config(struct udevice * dev,uint channel,uint period_ns,uint duty_ns)53 static int sandbox_pwm_set_config(struct udevice *dev, uint channel,
54 uint period_ns, uint duty_ns)
55 {
56 struct sandbox_pwm_priv *priv = dev_get_priv(dev);
57 struct sandbox_pwm_chan *chan;
58
59 if (channel >= NUM_CHANNELS)
60 return -ENOSPC;
61 chan = &priv->chan[channel];
62
63 if (channel == 2) {
64 /* Pretend to have some fixed period */
65 chan->period_ns = 4096;
66 chan->duty_ns = duty_ns * 4096 / period_ns;
67 } else {
68 chan->period_ns = period_ns;
69 chan->duty_ns = duty_ns;
70 }
71
72 return 0;
73 }
74
sandbox_pwm_set_enable(struct udevice * dev,uint channel,bool enable)75 static int sandbox_pwm_set_enable(struct udevice *dev, uint channel,
76 bool enable)
77 {
78 struct sandbox_pwm_priv *priv = dev_get_priv(dev);
79 struct sandbox_pwm_chan *chan;
80
81 if (channel >= NUM_CHANNELS)
82 return -ENOSPC;
83 chan = &priv->chan[channel];
84 chan->enable = enable;
85
86 return 0;
87 }
88
sandbox_pwm_set_invert(struct udevice * dev,uint channel,bool polarity)89 static int sandbox_pwm_set_invert(struct udevice *dev, uint channel,
90 bool polarity)
91 {
92 struct sandbox_pwm_priv *priv = dev_get_priv(dev);
93 struct sandbox_pwm_chan *chan;
94
95 if (channel >= NUM_CHANNELS)
96 return -ENOSPC;
97 chan = &priv->chan[channel];
98 chan->polarity = polarity;
99
100 return 0;
101 }
102
103 static const struct pwm_ops sandbox_pwm_ops = {
104 .set_config = sandbox_pwm_set_config,
105 .set_enable = sandbox_pwm_set_enable,
106 .set_invert = sandbox_pwm_set_invert,
107 };
108
109 static const struct udevice_id sandbox_pwm_ids[] = {
110 { .compatible = "sandbox,pwm" },
111 { }
112 };
113
114 U_BOOT_DRIVER(warm_pwm_sandbox) = {
115 .name = "pwm_sandbox",
116 .id = UCLASS_PWM,
117 .of_match = sandbox_pwm_ids,
118 .ops = &sandbox_pwm_ops,
119 .priv_auto = sizeof(struct sandbox_pwm_priv),
120 };
121