xref: /openbmc/u-boot/drivers/pwm/pwm-imx.c (revision d5abcf94)
1 /*
2  * (C) Copyright 2014
3  * Heiko Schocher, DENX Software Engineering, hs@denx.de.
4  *
5  * Basic support for the pwm module on imx6.
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 #include <div64.h>
12 #include <pwm.h>
13 #include <asm/arch/imx-regs.h>
14 #include <asm/io.h>
15 #include "pwm-imx-util.h"
16 
17 int pwm_init(int pwm_id, int div, int invert)
18 {
19 	struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
20 
21 	if (!pwm)
22 		return -1;
23 
24 	writel(0, &pwm->ir);
25 	return 0;
26 }
27 
28 int pwm_config(int pwm_id, int duty_ns, int period_ns)
29 {
30 	struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
31 	unsigned long period_cycles, duty_cycles, prescale;
32 	u32 cr;
33 
34 	if (!pwm)
35 		return -1;
36 
37 	pwm_imx_get_parms(period_ns, duty_ns, &period_cycles, &duty_cycles,
38 			  &prescale);
39 
40 	cr = PWMCR_PRESCALER(prescale) |
41 		PWMCR_DOZEEN | PWMCR_WAITEN |
42 		PWMCR_DBGEN | PWMCR_CLKSRC_IPG_HIGH;
43 
44 	writel(cr, &pwm->cr);
45 	/* set duty cycles */
46 	writel(duty_cycles, &pwm->sar);
47 	/* set period cycles */
48 	writel(period_cycles, &pwm->pr);
49 	return 0;
50 }
51 
52 int pwm_enable(int pwm_id)
53 {
54 	struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
55 
56 	if (!pwm)
57 		return -1;
58 
59 	setbits_le32(&pwm->cr, PWMCR_EN);
60 	return 0;
61 }
62 
63 void pwm_disable(int pwm_id)
64 {
65 	struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
66 
67 	if (!pwm)
68 		return;
69 
70 	clrbits_le32(&pwm->cr, PWMCR_EN);
71 }
72