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Heiko Schocher2b387762014-07-18 06:07:19 +02001/*
2 * (C) Copyright 2014
3 * Heiko Schocher, DENX Software Engineering, hs@denx.de.
4 *
Robert P. J. Day1f8378a2016-09-13 08:35:18 -04005 * Basic support for the pwm module on imx6.
Heiko Schocher2b387762014-07-18 06:07:19 +02006 *
7 * Based on linux:drivers/pwm/pwm-imx.c
8 * from
9 * Sascha Hauer <s.hauer@pengutronix.de>
10 *
11 * SPDX-License-Identifier: GPL-2.0
12 */
13
14#include <common.h>
15#include <div64.h>
16#include <asm/arch/imx-regs.h>
17
Christoph Fritzd1942f52016-11-22 12:01:28 +010018/* pwm_id from 0..7 */
Heiko Schocher2b387762014-07-18 06:07:19 +020019struct pwm_regs *pwm_id_to_reg(int pwm_id)
20{
21 switch (pwm_id) {
22 case 0:
23 return (struct pwm_regs *)PWM1_BASE_ADDR;
Heiko Schocher2b387762014-07-18 06:07:19 +020024 case 1:
25 return (struct pwm_regs *)PWM2_BASE_ADDR;
Martyn Welcha87af132017-11-08 15:35:11 +000026#ifdef CONFIG_MX6
Heiko Schocher2b387762014-07-18 06:07:19 +020027 case 2:
28 return (struct pwm_regs *)PWM3_BASE_ADDR;
Heiko Schocher2b387762014-07-18 06:07:19 +020029 case 3:
30 return (struct pwm_regs *)PWM4_BASE_ADDR;
Martyn Welcha87af132017-11-08 15:35:11 +000031#endif
Christoph Fritzd1942f52016-11-22 12:01:28 +010032#ifdef CONFIG_MX6SX
33 case 4:
34 return (struct pwm_regs *)PWM5_BASE_ADDR;
35 case 5:
36 return (struct pwm_regs *)PWM6_BASE_ADDR;
37 case 6:
38 return (struct pwm_regs *)PWM7_BASE_ADDR;
39 case 7:
40 return (struct pwm_regs *)PWM8_BASE_ADDR;
41#endif
Heiko Schocher2b387762014-07-18 06:07:19 +020042 default:
43 printf("unknown pwm_id: %d\n", pwm_id);
44 break;
45 }
46 return NULL;
47}
48
49int pwm_imx_get_parms(int period_ns, int duty_ns, unsigned long *period_c,
50 unsigned long *duty_c, unsigned long *prescale)
51{
52 unsigned long long c;
53
54 /*
55 * we have not yet a clock framework for imx6, so add the clock
56 * value here as a define. Replace it when we have the clock
57 * framework.
58 */
59 c = CONFIG_IMX6_PWM_PER_CLK;
60 c = c * period_ns;
61 do_div(c, 1000000000);
62 *period_c = c;
63
64 *prescale = *period_c / 0x10000 + 1;
65
66 *period_c /= *prescale;
Brecht Neyrinck33d2d152015-05-06 09:57:48 +020067 c = *period_c * (unsigned long long)duty_ns;
Heiko Schocher2b387762014-07-18 06:07:19 +020068 do_div(c, period_ns);
69 *duty_c = c;
70
71 /*
72 * according to imx pwm RM, the real period value should be
73 * PERIOD value in PWMPR plus 2.
74 */
75 if (*period_c > 2)
76 *period_c -= 2;
77 else
78 *period_c = 0;
79
80 return 0;
81}