arch/arm/mach-footbridge/ebsa285.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/arch/arm/mach-footbridge/ebsa285.c
   4  *
   5  * EBSA285 machine fixup
   6  */
   7 #include <linux/init.h>
   8 #include <linux/io.h>
   9 #include <linux/spinlock.h>
  10 #include <linux/slab.h>
  11 #include <linux/leds.h>
  12
  13 #include <asm/hardware/dec21285.h>
  14 #include <asm/mach-types.h>
  15
  16 #include <asm/mach/arch.h>
  17
  18 #include "common.h"
  19
  20 /* LEDs */
  21 #if defined(CONFIG_NEW_LEDS) && defined(CONFIG_LEDS_CLASS)
  22 #define XBUS_AMBER_L    BIT(0)
  23 #define XBUS_GREEN_L    BIT(1)
  24 #define XBUS_RED_L      BIT(2)
  25 #define XBUS_TOGGLE     BIT(7)
  26
  27 struct ebsa285_led {
  28         struct led_classdev     cdev;
  29         u8                      mask;
  30 };
  31
  32 /*
  33  * The triggers lines up below will only be used if the
  34  * LED triggers are compiled in.
  35  */
  36 static const struct {
  37         const char *name;
  38         const char *trigger;
  39 } ebsa285_leds[] = {
  40         { "ebsa285:amber", "cpu0", },
  41         { "ebsa285:green", "heartbeat", },
  42         { "ebsa285:red",},
  43 };
  44
  45 static unsigned char hw_led_state;
  46 static void __iomem *xbus;
  47
  48 static void ebsa285_led_set(struct led_classdev *cdev,
  49                 enum led_brightness b)
  50 {
  51         struct ebsa285_led *led = container_of(cdev,
  52                         struct ebsa285_led, cdev);
  53
  54         if (b == LED_OFF)
  55                 hw_led_state |= led->mask;
  56         else
  57                 hw_led_state &= ~led->mask;
  58         writeb(hw_led_state, xbus);
  59 }
  60
  61 static enum led_brightness ebsa285_led_get(struct led_classdev *cdev)
  62 {
  63         struct ebsa285_led *led = container_of(cdev,
  64                         struct ebsa285_led, cdev);
  65
  66         return hw_led_state & led->mask ? LED_OFF : LED_FULL;
  67 }
  68
  69 static int __init ebsa285_leds_init(void)
  70 {
  71         int i;
  72
  73         if (!machine_is_ebsa285())
  74                 return -ENODEV;
  75
  76         xbus = ioremap(XBUS_CS2, SZ_4K);
  77         if (!xbus)
  78                 return -ENOMEM;
  79
  80         /* 3 LEDS all off */
  81         hw_led_state = XBUS_AMBER_L | XBUS_GREEN_L | XBUS_RED_L;
  82         writeb(hw_led_state, xbus);
  83
  84         for (i = 0; i < ARRAY_SIZE(ebsa285_leds); i++) {
  85                 struct ebsa285_led *led;
  86
  87                 led = kzalloc(sizeof(*led), GFP_KERNEL);
  88                 if (!led)
  89                         break;
  90
  91                 led->cdev.name = ebsa285_leds[i].name;
  92                 led->cdev.brightness_set = ebsa285_led_set;
  93                 led->cdev.brightness_get = ebsa285_led_get;
  94                 led->cdev.default_trigger = ebsa285_leds[i].trigger;
  95                 led->mask = BIT(i);
  96
  97                 if (led_classdev_register(NULL, &led->cdev) < 0) {
  98                         kfree(led);
  99                         break;
 100                 }
 101         }
 102
 103         return 0;
 104 }
 105
 106 /*
 107  * Since we may have triggers on any subsystem, defer registration
 108  * until after subsystem_init.
 109  */
 110 fs_initcall(ebsa285_leds_init);
 111 #endif
 112
 113 MACHINE_START(EBSA285, "EBSA285")
 114         /* Maintainer: Russell King */
 115         .atag_offset    = 0x100,
 116         .video_start    = 0x000a0000,
 117         .video_end      = 0x000bffff,
 118         .map_io         = footbridge_map_io,
 119         .init_early     = footbridge_sched_clock,
 120         .init_irq       = footbridge_init_irq,
 121         .init_time      = footbridge_timer_init,
 122         .restart        = footbridge_restart,
 123 MACHINE_END
 124