drivers/pwm/pwm-imx.c

   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
  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
  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
  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
  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
  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
  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
  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
 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(&regs->cr, PWMCR_EN);
 123         else
 124                 clrbits_le32(&regs->cr, PWMCR_EN);
 125
 126         return 0;
 127 };
 128
 129 static int imx_pwm_ofdata_to_platdata(struct udevice *dev)
 130 {
 131         struct imx_pwm_priv *priv = dev_get_priv(dev);
 132
 133         priv->regs = (struct pwm_regs *)devfdt_get_addr(dev);
 134
 135         return 0;
 136 }
 137
 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         .ofdata_to_platdata     = imx_pwm_ofdata_to_platdata,
 160         .probe          = imx_pwm_probe,
 161         .priv_auto_alloc_size   = sizeof(struct imx_pwm_priv),
 162 };
 163 #endif