drivers/pwm/pwm-imx.c

   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 }