drivers/pwm/rk_pwm.c

   1 /*
   2  * Copyright (c) 2016 Google, Inc
   3  * Written by Simon Glass <sjg@chromium.org>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <clk.h>
  10 #include <div64.h>
  11 #include <dm.h>
  12 #include <pwm.h>
  13 #include <regmap.h>
  14 #include <syscon.h>
  15 #include <asm/io.h>
  16 #include <asm/arch/pwm.h>
  17 #include <power/regulator.h>
  18
  19 DECLARE_GLOBAL_DATA_PTR;
  20
  21 struct rk_pwm_priv {
  22         struct rk3288_pwm *regs;
  23         ulong freq;
  24         uint enable_conf;
  25 };
  26
  27 static int rk_pwm_set_invert(struct udevice *dev, uint channel, bool polarity)
  28 {
  29         struct rk_pwm_priv *priv = dev_get_priv(dev);
  30
  31         debug("%s: polarity=%u\n", __func__, polarity);
  32         priv->enable_conf &= ~(PWM_DUTY_MASK | PWM_INACTIVE_MASK);
  33         if (polarity)
  34                 priv->enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSTIVE;
  35         else
  36                 priv->enable_conf |= PWM_DUTY_POSTIVE | PWM_INACTIVE_NEGATIVE;
  37
  38         return 0;
  39 }
  40
  41 static int rk_pwm_set_config(struct udevice *dev, uint channel, uint period_ns,
  42                              uint duty_ns)
  43 {
  44         struct rk_pwm_priv *priv = dev_get_priv(dev);
  45         struct rk3288_pwm *regs = priv->regs;
  46         unsigned long period, duty;
  47
  48         debug("%s: period_ns=%u, duty_ns=%u\n", __func__, period_ns, duty_ns);
  49         writel(PWM_SEL_SRC_CLK | PWM_OUTPUT_LEFT | PWM_LP_DISABLE |
  50                 PWM_CONTINUOUS | priv->enable_conf |
  51                 RK_PWM_DISABLE,
  52                 &regs->ctrl);
  53
  54         period = lldiv((uint64_t)(priv->freq / 1000) * period_ns, 1000000);
  55         duty = lldiv((uint64_t)(priv->freq / 1000) * duty_ns, 1000000);
  56
  57         writel(period, &regs->period_hpr);
  58         writel(duty, &regs->duty_lpr);
  59         debug("%s: period=%lu, duty=%lu\n", __func__, period, duty);
  60
  61         return 0;
  62 }
  63
  64 static int rk_pwm_set_enable(struct udevice *dev, uint channel, bool enable)
  65 {
  66         struct rk_pwm_priv *priv = dev_get_priv(dev);
  67         struct rk3288_pwm *regs = priv->regs;
  68
  69         debug("%s: Enable '%s'\n", __func__, dev->name);
  70         clrsetbits_le32(&regs->ctrl, RK_PWM_ENABLE, enable ? RK_PWM_ENABLE : 0);
  71
  72         return 0;
  73 }
  74
  75 static int rk_pwm_ofdata_to_platdata(struct udevice *dev)
  76 {
  77         struct rk_pwm_priv *priv = dev_get_priv(dev);
  78
  79         priv->regs = (struct rk3288_pwm *)devfdt_get_addr(dev);
  80
  81         return 0;
  82 }
  83
  84 static int rk_pwm_probe(struct udevice *dev)
  85 {
  86         struct rk_pwm_priv *priv = dev_get_priv(dev);
  87         struct clk clk;
  88         int ret = 0;
  89
  90         ret = clk_get_by_index(dev, 0, &clk);
  91         if (ret < 0) {
  92                 debug("%s get clock fail!\n", __func__);
  93                 return -EINVAL;
  94         }
  95         priv->freq = clk_get_rate(&clk);
  96         priv->enable_conf = PWM_DUTY_POSTIVE | PWM_INACTIVE_POSTIVE;
  97
  98         return 0;
  99 }
 100
 101 static const struct pwm_ops rk_pwm_ops = {
 102         .set_invert     = rk_pwm_set_invert,
 103         .set_config     = rk_pwm_set_config,
 104         .set_enable     = rk_pwm_set_enable,
 105 };
 106
 107 static const struct udevice_id rk_pwm_ids[] = {
 108         { .compatible = "rockchip,rk3288-pwm" },
 109         { }
 110 };
 111
 112 U_BOOT_DRIVER(rk_pwm) = {
 113         .name   = "rk_pwm",
 114         .id     = UCLASS_PWM,
 115         .of_match = rk_pwm_ids,
 116         .ops    = &rk_pwm_ops,
 117         .ofdata_to_platdata     = rk_pwm_ofdata_to_platdata,
 118         .probe          = rk_pwm_probe,
 119         .priv_auto_alloc_size   = sizeof(struct rk_pwm_priv),
 120 };