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 DECLARE_GLOBAL_DATA_PTR;
  35
  36 struct bcm6358_led_priv {
  37         void __iomem *regs;
  38         uint8_t pin;
  39         bool active_low;
  40 };
  41
  42 static void bcm6358_led_busy(void __iomem *regs)
  43 {
  44         while (readl_be(regs + LED_CTRL_REG) & LED_CTRL_BUSY_MASK)
  45                 udelay(LEDS_WAIT);
  46 }
  47
  48 static unsigned long bcm6358_led_get_mode(struct bcm6358_led_priv *priv)
  49 {
  50         bcm6358_led_busy(priv->regs);
  51
  52         return (readl_be(priv->regs + LED_MODE_REG) >> priv->pin) &
  53                LED_MODE_MASK;
  54 }
  55
  56 static int bcm6358_led_set_mode(struct bcm6358_led_priv *priv, uint8_t mode)
  57 {
  58         bcm6358_led_busy(priv->regs);
  59
  60         clrsetbits_be32(priv->regs + LED_MODE_REG,
  61                         (LED_MODE_MASK << priv->pin),
  62                         (mode << priv->pin));
  63
  64         return 0;
  65 }
  66
  67 static enum led_state_t bcm6358_led_get_state(struct udevice *dev)
  68 {
  69         struct bcm6358_led_priv *priv = dev_get_priv(dev);
  70         enum led_state_t state = LEDST_OFF;
  71
  72         switch (bcm6358_led_get_mode(priv)) {
  73         case LED_MODE_OFF:
  74                 state = (priv->active_low ? LEDST_ON : LEDST_OFF);
  75                 break;
  76         case LED_MODE_ON:
  77                 state = (priv->active_low ? LEDST_OFF : LEDST_ON);
  78                 break;
  79         }
  80
  81         return state;
  82 }
  83
  84 static int bcm6358_led_set_state(struct udevice *dev, enum led_state_t state)
  85 {
  86         struct bcm6358_led_priv *priv = dev_get_priv(dev);
  87         unsigned long mode;
  88
  89         switch (state) {
  90         case LEDST_OFF:
  91                 mode = (priv->active_low ? LED_MODE_ON : LED_MODE_OFF);
  92                 break;
  93         case LEDST_ON:
  94                 mode = (priv->active_low ? LED_MODE_OFF : LED_MODE_ON);
  95                 break;
  96         case LEDST_TOGGLE:
  97                 if (bcm6358_led_get_state(dev) == LEDST_OFF)
  98                         return bcm6358_led_set_state(dev, LEDST_ON);
  99                 else
 100                         return bcm6358_led_set_state(dev, LEDST_OFF);
 101                 break;
 102         default:
 103                 return -ENOSYS;
 104         }
 105
 106         return bcm6358_led_set_mode(priv, mode);
 107 }
 108
 109 static const struct led_ops bcm6358_led_ops = {
 110         .get_state = bcm6358_led_get_state,
 111         .set_state = bcm6358_led_set_state,
 112 };
 113
 114 static int bcm6358_led_probe(struct udevice *dev)
 115 {
 116         struct led_uc_plat *uc_plat = dev_get_uclass_platdata(dev);
 117         fdt_addr_t addr;
 118         fdt_size_t size;
 119
 120         /* Top-level LED node */
 121         if (!uc_plat->label) {
 122                 void __iomem *regs;
 123                 unsigned int clk_div;
 124                 u32 set_bits = 0;
 125
 126                 addr = devfdt_get_addr_size_index(dev, 0, &size);
 127                 if (addr == FDT_ADDR_T_NONE)
 128                         return -EINVAL;
 129
 130                 regs = ioremap(addr, size);
 131
 132                 if (fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev),
 133                                     "brcm,clk-dat-low"))
 134                         set_bits |= LED_CTRL_POL_MASK;
 135                 clk_div = fdtdec_get_uint(gd->fdt_blob, dev_of_offset(dev),
 136                                           "brcm,clk-div", LED_CTRL_CLK_1);
 137                 switch (clk_div) {
 138                 case 8:
 139                         set_bits |= LED_CTRL_CLK_8;
 140                         break;
 141                 case 4:
 142                         set_bits |= LED_CTRL_CLK_4;
 143                         break;
 144                 case 2:
 145                         set_bits |= LED_CTRL_CLK_2;
 146                         break;
 147                 default:
 148                         set_bits |= LED_CTRL_CLK_1;
 149                         break;
 150                 }
 151
 152                 bcm6358_led_busy(regs);
 153                 clrsetbits_be32(regs + LED_CTRL_REG,
 154                                 LED_CTRL_POL_MASK | LED_CTRL_CLK_MASK,
 155                                 set_bits);
 156         } else {
 157                 struct bcm6358_led_priv *priv = dev_get_priv(dev);
 158                 unsigned int pin;
 159
 160                 addr = devfdt_get_addr_size_index(dev_get_parent(dev), 0,
 161                                                   &size);
 162                 if (addr == FDT_ADDR_T_NONE)
 163                         return -EINVAL;
 164
 165                 pin = fdtdec_get_uint(gd->fdt_blob, dev_of_offset(dev), "reg",
 166                                       LEDS_MAX);
 167                 if (pin >= LEDS_MAX)
 168                         return -EINVAL;
 169
 170                 priv->regs = ioremap(addr, size);
 171                 priv->pin = pin;
 172
 173                 if (fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev),
 174                                     "active-low"))
 175                         priv->active_low = true;
 176         }
 177
 178         return 0;
 179 }
 180
 181 static int bcm6358_led_bind(struct udevice *parent)
 182 {
 183         const void *blob = gd->fdt_blob;
 184         int node;
 185
 186         for (node = fdt_first_subnode(blob, dev_of_offset(parent));
 187              node > 0;
 188              node = fdt_next_subnode(blob, node)) {
 189                 struct led_uc_plat *uc_plat;
 190                 struct udevice *dev;
 191                 const char *label;
 192                 int ret;
 193
 194                 label = fdt_getprop(blob, node, "label", NULL);
 195                 if (!label) {
 196                         debug("%s: node %s has no label\n", __func__,
 197                               fdt_get_name(blob, node, NULL));
 198                         return -EINVAL;
 199                 }
 200
 201                 ret = device_bind_driver_to_node(parent, "bcm6358-led",
 202                                                  fdt_get_name(blob, node, NULL),
 203                                                  offset_to_ofnode(node), &dev);
 204                 if (ret)
 205                         return ret;
 206
 207                 uc_plat = dev_get_uclass_platdata(dev);
 208                 uc_plat->label = label;
 209         }
 210
 211         return 0;
 212 }
 213
 214 static const struct udevice_id bcm6358_led_ids[] = {
 215         { .compatible = "brcm,bcm6358-leds" },
 216         { /* sentinel */ }
 217 };
 218
 219 U_BOOT_DRIVER(bcm6358_led) = {
 220         .name = "bcm6358-led",
 221         .id = UCLASS_LED,
 222         .of_match = bcm6358_led_ids,
 223         .bind = bcm6358_led_bind,
 224         .probe = bcm6358_led_probe,
 225         .priv_auto_alloc_size = sizeof(struct bcm6358_led_priv),
 226         .ops = &bcm6358_led_ops,
 227 };