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 <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_internal(struct pwm_regs *pwm, unsigned long period_cycles,
  29                         unsigned long duty_cycles, unsigned long prescale)
  30 {
  31         u32 cr;
  32
  33         writel(0, &pwm->ir);
  34         cr = PWMCR_PRESCALER(prescale) |
  35                 PWMCR_DOZEEN | PWMCR_WAITEN |
  36                 PWMCR_DBGEN | PWMCR_CLKSRC_IPG_HIGH;
  37
  38         writel(cr, &pwm->cr);
  39         /* set duty cycles */
  40         writel(duty_cycles, &pwm->sar);
  41         /* set period cycles */
  42         writel(period_cycles, &pwm->pr);
  43         return 0;
  44 }
  45
  46 int pwm_config(int pwm_id, int duty_ns, int period_ns)
  47 {
  48         struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
  49         unsigned long period_cycles, duty_cycles, prescale;
  50
  51         if (!pwm)
  52                 return -1;
  53
  54         pwm_imx_get_parms(period_ns, duty_ns, &period_cycles, &duty_cycles,
  55                           &prescale);
  56
  57         return pwm_config_internal(pwm, period_cycles, duty_cycles, prescale);
  58 }
  59
  60 int pwm_enable(int pwm_id)
  61 {
  62         struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
  63
  64         if (!pwm)
  65                 return -1;
  66
  67         setbits_le32(&pwm->cr, PWMCR_EN);
  68         return 0;
  69 }
  70
  71 void pwm_disable(int pwm_id)
  72 {
  73         struct pwm_regs *pwm = (struct pwm_regs *)pwm_id_to_reg(pwm_id);
  74
  75         if (!pwm)
  76                 return;
  77
  78         clrbits_le32(&pwm->cr, PWMCR_EN);
  79 }
  80
  81 #if defined(CONFIG_DM_PWM)
  82 struct imx_pwm_priv {
  83         struct pwm_regs *regs;
  84         bool invert;
  85 };
  86
  87 static int imx_pwm_set_invert(struct udevice *dev, uint channel,
  88                               bool polarity)
  89 {
  90         struct imx_pwm_priv *priv = dev_get_priv(dev);
  91
  92         debug("%s: polarity=%u\n", __func__, polarity);
  93         priv->invert = polarity;
  94
  95         return 0;
  96 }
  97
  98 static int imx_pwm_set_config(struct udevice *dev, uint channel,
  99                               uint period_ns, uint duty_ns)
 100 {
 101         struct imx_pwm_priv *priv = dev_get_priv(dev);
 102         struct pwm_regs *regs = priv->regs;
 103         unsigned long period_cycles, duty_cycles, prescale;
 104
 105         debug("%s: Config '%s' channel: %d\n", __func__, dev->name, channel);
 106
 107         pwm_imx_get_parms(period_ns, duty_ns, &period_cycles, &duty_cycles,
 108                           &prescale);
 109
 110         return pwm_config_internal(regs, period_cycles, duty_cycles, prescale);
 111 };
 112
 113 static int imx_pwm_set_enable(struct udevice *dev, uint channel, bool enable)
 114 {
 115         struct imx_pwm_priv *priv = dev_get_priv(dev);
 116         struct pwm_regs *regs = priv->regs;
 117
 118         debug("%s: Enable '%s' state: %d\n", __func__, dev->name, enable);
 119
 120         if (enable)
 121                 setbits_le32(&regs->cr, PWMCR_EN);
 122         else
 123                 clrbits_le32(&regs->cr, PWMCR_EN);
 124
 125         return 0;
 126 };
 127
 128 static int imx_pwm_ofdata_to_platdata(struct udevice *dev)
 129 {
 130         struct imx_pwm_priv *priv = dev_get_priv(dev);
 131
 132         priv->regs = (struct pwm_regs *)devfdt_get_addr(dev);
 133
 134         return 0;
 135 }
 136
 137 static int imx_pwm_probe(struct udevice *dev)
 138 {
 139         return 0;
 140 }
 141
 142 static const struct pwm_ops imx_pwm_ops = {
 143         .set_invert     = imx_pwm_set_invert,
 144         .set_config     = imx_pwm_set_config,
 145         .set_enable     = imx_pwm_set_enable,
 146 };
 147
 148 static const struct udevice_id imx_pwm_ids[] = {
 149         { .compatible = "fsl,imx27-pwm" },
 150         { }
 151 };
 152
 153 U_BOOT_DRIVER(imx_pwm) = {
 154         .name   = "imx_pwm",
 155         .id     = UCLASS_PWM,
 156         .of_match = imx_pwm_ids,
 157         .ops    = &imx_pwm_ops,
 158         .ofdata_to_platdata     = imx_pwm_ofdata_to_platdata,
 159         .probe          = imx_pwm_probe,
 160         .priv_auto_alloc_size   = sizeof(struct imx_pwm_priv),
 161 };
 162 #endif