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         if (polarity)
  33                 priv->enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSTIVE;
  34         else
  35                 priv->enable_conf |= PWM_DUTY_POSTIVE | PWM_INACTIVE_NEGATIVE;
  36
  37         return 0;
  38 }
  39
  40 static int rk_pwm_set_config(struct udevice *dev, uint channel, uint period_ns,
  41                              uint duty_ns)
  42 {
  43         struct rk_pwm_priv *priv = dev_get_priv(dev);
  44         struct rk3288_pwm *regs = priv->regs;
  45         unsigned long period, duty;
  46
  47         debug("%s: period_ns=%u, duty_ns=%u\n", __func__, period_ns, duty_ns);
  48         writel(PWM_SEL_SRC_CLK | PWM_OUTPUT_LEFT | PWM_LP_DISABLE |
  49                 PWM_CONTINUOUS | priv->enable_conf |
  50                 RK_PWM_DISABLE,
  51                 &regs->ctrl);
  52
  53         period = lldiv((uint64_t)(priv->freq / 1000) * period_ns, 1000000);
  54         duty = lldiv((uint64_t)(priv->freq / 1000) * duty_ns, 1000000);
  55
  56         writel(period, &regs->period_hpr);
  57         writel(duty, &regs->duty_lpr);
  58         debug("%s: period=%lu, duty=%lu\n", __func__, period, duty);
  59
  60         return 0;
  61 }
  62
  63 static int rk_pwm_set_enable(struct udevice *dev, uint channel, bool enable)
  64 {
  65         struct rk_pwm_priv *priv = dev_get_priv(dev);
  66         struct rk3288_pwm *regs = priv->regs;
  67
  68         debug("%s: Enable '%s'\n", __func__, dev->name);
  69         clrsetbits_le32(&regs->ctrl, RK_PWM_ENABLE, enable ? RK_PWM_ENABLE : 0);
  70
  71         return 0;
  72 }
  73
  74 static int rk_pwm_ofdata_to_platdata(struct udevice *dev)
  75 {
  76         struct rk_pwm_priv *priv = dev_get_priv(dev);
  77
  78         priv->regs = (struct rk3288_pwm *)devfdt_get_addr(dev);
  79
  80         return 0;
  81 }
  82
  83 static int rk_pwm_probe(struct udevice *dev)
  84 {
  85         struct rk_pwm_priv *priv = dev_get_priv(dev);
  86         struct clk clk;
  87         int ret = 0;
  88
  89         ret = clk_get_by_index(dev, 0, &clk);
  90         if (ret < 0) {
  91                 debug("%s get clock fail!\n", __func__);
  92                 return -EINVAL;
  93         }
  94         priv->freq = clk_get_rate(&clk);
  95         priv->enable_conf = PWM_DUTY_POSTIVE | PWM_INACTIVE_POSTIVE;
  96
  97         return 0;
  98 }
  99
 100 static const struct pwm_ops rk_pwm_ops = {
 101         .set_invert     = rk_pwm_set_invert,
 102         .set_config     = rk_pwm_set_config,
 103         .set_enable     = rk_pwm_set_enable,
 104 };
 105
 106 static const struct udevice_id rk_pwm_ids[] = {
 107         { .compatible = "rockchip,rk3288-pwm" },
 108         { }
 109 };
 110
 111 U_BOOT_DRIVER(rk_pwm) = {
 112         .name   = "rk_pwm",
 113         .id     = UCLASS_PWM,
 114         .of_match = rk_pwm_ids,
 115         .ops    = &rk_pwm_ops,
 116         .ofdata_to_platdata     = rk_pwm_ofdata_to_platdata,
 117         .probe          = rk_pwm_probe,
 118         .priv_auto_alloc_size   = sizeof(struct rk_pwm_priv),
 119 };