git.sur5r.net Git - u-boot/blob - drivers/led/led_bcm6358.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
   4  */
   5
   6 #include <common.h>
   7 #include <dm.h>
   8 #include <errno.h>
   9 #include <led.h>
  10 #include <asm/io.h>
  11 #include <dm/lists.h>
  12
  13 #define LEDS_MAX                32
  14 #define LEDS_WAIT               100
  15
  16 /* LED Mode register */
  17 #define LED_MODE_REG            0x0
  18 #define LED_MODE_OFF            0
  19 #define LED_MODE_ON             1
  20 #define LED_MODE_MASK           1
  21
  22 /* LED Control register */
  23 #define LED_CTRL_REG            0x4
  24 #define LED_CTRL_CLK_MASK       0x3
  25 #define LED_CTRL_CLK_1          0
  26 #define LED_CTRL_CLK_2          1
  27 #define LED_CTRL_CLK_4          2
  28 #define LED_CTRL_CLK_8          3
  29 #define LED_CTRL_POL_SHIFT      2
  30 #define LED_CTRL_POL_MASK       (1 << LED_CTRL_POL_SHIFT)
  31 #define LED_CTRL_BUSY_SHIFT     3
  32 #define LED_CTRL_BUSY_MASK      (1 << LED_CTRL_BUSY_SHIFT)
  33
  34 struct bcm6358_led_priv {
  35         void __iomem *regs;
  36         uint8_t pin;
  37         bool active_low;
  38 };
  39
  40 static void bcm6358_led_busy(void __iomem *regs)
  41 {
  42         while (readl_be(regs + LED_CTRL_REG) & LED_CTRL_BUSY_MASK)
  43                 udelay(LEDS_WAIT);
  44 }
  45
  46 static unsigned long bcm6358_led_get_mode(struct bcm6358_led_priv *priv)
  47 {
  48         bcm6358_led_busy(priv->regs);
  49
  50         return (readl_be(priv->regs + LED_MODE_REG) >> priv->pin) &
  51                LED_MODE_MASK;
  52 }
  53
  54 static int bcm6358_led_set_mode(struct bcm6358_led_priv *priv, uint8_t mode)
  55 {
  56         bcm6358_led_busy(priv->regs);
  57
  58         clrsetbits_be32(priv->regs + LED_MODE_REG,
  59                         (LED_MODE_MASK << priv->pin),
  60                         (mode << priv->pin));
  61
  62         return 0;
  63 }
  64
  65 static enum led_state_t bcm6358_led_get_state(struct udevice *dev)
  66 {
  67         struct bcm6358_led_priv *priv = dev_get_priv(dev);
  68         enum led_state_t state = LEDST_OFF;
  69
  70         switch (bcm6358_led_get_mode(priv)) {
  71         case LED_MODE_OFF:
  72                 state = (priv->active_low ? LEDST_ON : LEDST_OFF);
  73                 break;
  74         case LED_MODE_ON:
  75                 state = (priv->active_low ? LEDST_OFF : LEDST_ON);
  76                 break;
  77         }
  78
  79         return state;
  80 }
  81
  82 static int bcm6358_led_set_state(struct udevice *dev, enum led_state_t state)
  83 {
  84         struct bcm6358_led_priv *priv = dev_get_priv(dev);
  85         unsigned long mode;
  86
  87         switch (state) {
  88         case LEDST_OFF:
  89                 mode = (priv->active_low ? LED_MODE_ON : LED_MODE_OFF);
  90                 break;
  91         case LEDST_ON:
  92                 mode = (priv->active_low ? LED_MODE_OFF : LED_MODE_ON);
  93                 break;
  94         case LEDST_TOGGLE:
  95                 if (bcm6358_led_get_state(dev) == LEDST_OFF)
  96                         return bcm6358_led_set_state(dev, LEDST_ON);
  97                 else
  98                         return bcm6358_led_set_state(dev, LEDST_OFF);
  99                 break;
 100         default:
 101                 return -ENOSYS;
 102         }
 103
 104         return bcm6358_led_set_mode(priv, mode);
 105 }
 106
 107 static const struct led_ops bcm6358_led_ops = {
 108         .get_state = bcm6358_led_get_state,
 109         .set_state = bcm6358_led_set_state,
 110 };
 111
 112 static int bcm6358_led_probe(struct udevice *dev)
 113 {
 114         struct led_uc_plat *uc_plat = dev_get_uclass_platdata(dev);
 115
 116         /* Top-level LED node */
 117         if (!uc_plat->label) {
 118                 void __iomem *regs;
 119                 unsigned int clk_div;
 120                 u32 set_bits = 0;
 121
 122                 regs = dev_remap_addr(dev);
 123                 if (!regs)
 124                         return -EINVAL;
 125
 126                 if (dev_read_bool(dev, "brcm,clk-dat-low"))
 127                         set_bits |= LED_CTRL_POL_MASK;
 128                 clk_div = dev_read_u32_default(dev, "brcm,clk-div",
 129                                                LED_CTRL_CLK_1);
 130                 switch (clk_div) {
 131                 case 8:
 132                         set_bits |= LED_CTRL_CLK_8;
 133                         break;
 134                 case 4:
 135                         set_bits |= LED_CTRL_CLK_4;
 136                         break;
 137                 case 2:
 138                         set_bits |= LED_CTRL_CLK_2;
 139                         break;
 140                 default:
 141                         set_bits |= LED_CTRL_CLK_1;
 142                         break;
 143                 }
 144
 145                 bcm6358_led_busy(regs);
 146                 clrsetbits_be32(regs + LED_CTRL_REG,
 147                                 LED_CTRL_POL_MASK | LED_CTRL_CLK_MASK,
 148                                 set_bits);
 149         } else {
 150                 struct bcm6358_led_priv *priv = dev_get_priv(dev);
 151                 unsigned int pin;
 152
 153                 priv->regs = dev_remap_addr(dev);
 154                 if (!priv->regs)
 155                         return -EINVAL;
 156
 157                 pin = dev_read_u32_default(dev, "reg", LEDS_MAX);
 158                 if (pin >= LEDS_MAX)
 159                         return -EINVAL;
 160
 161                 priv->pin = pin;
 162
 163                 if (dev_read_bool(dev, "active-low"))
 164                         priv->active_low = true;
 165         }
 166
 167         return 0;
 168 }
 169
 170 static int bcm6358_led_bind(struct udevice *parent)
 171 {
 172         ofnode node;
 173
 174         dev_for_each_subnode(node, parent) {
 175                 struct led_uc_plat *uc_plat;
 176                 struct udevice *dev;
 177                 const char *label;
 178                 int ret;
 179
 180                 label = ofnode_read_string(node, "label");
 181                 if (!label) {
 182                         debug("%s: node %s has no label\n", __func__,
 183                               ofnode_get_name(node));
 184                         return -EINVAL;
 185                 }
 186
 187                 ret = device_bind_driver_to_node(parent, "bcm6358-led",
 188                                                  ofnode_get_name(node),
 189                                                  node, &dev);
 190                 if (ret)
 191                         return ret;
 192
 193                 uc_plat = dev_get_uclass_platdata(dev);
 194                 uc_plat->label = label;
 195         }
 196
 197         return 0;
 198 }
 199
 200 static const struct udevice_id bcm6358_led_ids[] = {
 201         { .compatible = "brcm,bcm6358-leds" },
 202         { /* sentinel */ }
 203 };
 204
 205 U_BOOT_DRIVER(bcm6358_led) = {
 206         .name = "bcm6358-led",
 207         .id = UCLASS_LED,
 208         .of_match = bcm6358_led_ids,
 209         .bind = bcm6358_led_bind,
 210         .probe = bcm6358_led_probe,
 211         .priv_auto_alloc_size = sizeof(struct bcm6358_led_priv),
 212         .ops = &bcm6358_led_ops,
 213 };