drivers/ssb/driver_gpio.c

   1 /*
   2  * Sonics Silicon Backplane
   3  * GPIO driver
   4  *
   5  * Copyright 2011, Broadcom Corporation
   6  * Copyright 2012, Hauke Mehrtens <hauke@hauke-m.de>
   7  *
   8  * Licensed under the GNU/GPL. See COPYING for details.
   9  */
  10
  11 #include <linux/gpio.h>
  12 #include <linux/export.h>
  13 #include <linux/ssb/ssb.h>
  14
  15 #include "ssb_private.h"
  16
  17 static struct ssb_bus *ssb_gpio_get_bus(struct gpio_chip *chip)
  18 {
  19         return container_of(chip, struct ssb_bus, gpio);
  20 }
  21
  22 static int ssb_gpio_chipco_get_value(struct gpio_chip *chip, unsigned gpio)
  23 {
  24         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
  25
  26         return !!ssb_chipco_gpio_in(&bus->chipco, 1 << gpio);
  27 }
  28
  29 static void ssb_gpio_chipco_set_value(struct gpio_chip *chip, unsigned gpio,
  30                                       int value)
  31 {
  32         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
  33
  34         ssb_chipco_gpio_out(&bus->chipco, 1 << gpio, value ? 1 << gpio : 0);
  35 }
  36
  37 static int ssb_gpio_chipco_direction_input(struct gpio_chip *chip,
  38                                            unsigned gpio)
  39 {
  40         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
  41
  42         ssb_chipco_gpio_outen(&bus->chipco, 1 << gpio, 0);
  43         return 0;
  44 }
  45
  46 static int ssb_gpio_chipco_direction_output(struct gpio_chip *chip,
  47                                             unsigned gpio, int value)
  48 {
  49         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
  50
  51         ssb_chipco_gpio_outen(&bus->chipco, 1 << gpio, 1 << gpio);
  52         ssb_chipco_gpio_out(&bus->chipco, 1 << gpio, value ? 1 << gpio : 0);
  53         return 0;
  54 }
  55
  56 static int ssb_gpio_chipco_request(struct gpio_chip *chip, unsigned gpio)
  57 {
  58         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
  59
  60         ssb_chipco_gpio_control(&bus->chipco, 1 << gpio, 0);
  61         /* clear pulldown */
  62         ssb_chipco_gpio_pulldown(&bus->chipco, 1 << gpio, 0);
  63         /* Set pullup */
  64         ssb_chipco_gpio_pullup(&bus->chipco, 1 << gpio, 1 << gpio);
  65
  66         return 0;
  67 }
  68
  69 static void ssb_gpio_chipco_free(struct gpio_chip *chip, unsigned gpio)
  70 {
  71         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
  72
  73         /* clear pullup */
  74         ssb_chipco_gpio_pullup(&bus->chipco, 1 << gpio, 0);
  75 }
  76
  77 static int ssb_gpio_chipco_to_irq(struct gpio_chip *chip, unsigned gpio)
  78 {
  79         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
  80
  81         if (bus->bustype == SSB_BUSTYPE_SSB)
  82                 return ssb_mips_irq(bus->chipco.dev) + 2;
  83         else
  84                 return -EINVAL;
  85 }
  86
  87 static int ssb_gpio_chipco_init(struct ssb_bus *bus)
  88 {
  89         struct gpio_chip *chip = &bus->gpio;
  90
  91         chip->label             = "ssb_chipco_gpio";
  92         chip->owner             = THIS_MODULE;
  93         chip->request           = ssb_gpio_chipco_request;
  94         chip->free              = ssb_gpio_chipco_free;
  95         chip->get               = ssb_gpio_chipco_get_value;
  96         chip->set               = ssb_gpio_chipco_set_value;
  97         chip->direction_input   = ssb_gpio_chipco_direction_input;
  98         chip->direction_output  = ssb_gpio_chipco_direction_output;
  99         chip->to_irq            = ssb_gpio_chipco_to_irq;
 100         chip->ngpio             = 16;
 101         /* There is just one SoC in one device and its GPIO addresses should be
 102          * deterministic to address them more easily. The other buses could get
 103          * a random base number. */
 104         if (bus->bustype == SSB_BUSTYPE_SSB)
 105                 chip->base              = 0;
 106         else
 107                 chip->base              = -1;
 108
 109         return gpiochip_add(chip);
 110 }
 111
 112 #ifdef CONFIG_SSB_DRIVER_EXTIF
 113
 114 static int ssb_gpio_extif_get_value(struct gpio_chip *chip, unsigned gpio)
 115 {
 116         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
 117
 118         return !!ssb_extif_gpio_in(&bus->extif, 1 << gpio);
 119 }
 120
 121 static void ssb_gpio_extif_set_value(struct gpio_chip *chip, unsigned gpio,
 122                                      int value)
 123 {
 124         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
 125
 126         ssb_extif_gpio_out(&bus->extif, 1 << gpio, value ? 1 << gpio : 0);
 127 }
 128
 129 static int ssb_gpio_extif_direction_input(struct gpio_chip *chip,
 130                                           unsigned gpio)
 131 {
 132         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
 133
 134         ssb_extif_gpio_outen(&bus->extif, 1 << gpio, 0);
 135         return 0;
 136 }
 137
 138 static int ssb_gpio_extif_direction_output(struct gpio_chip *chip,
 139                                            unsigned gpio, int value)
 140 {
 141         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
 142
 143         ssb_extif_gpio_outen(&bus->extif, 1 << gpio, 1 << gpio);
 144         ssb_extif_gpio_out(&bus->extif, 1 << gpio, value ? 1 << gpio : 0);
 145         return 0;
 146 }
 147
 148 static int ssb_gpio_extif_to_irq(struct gpio_chip *chip, unsigned gpio)
 149 {
 150         struct ssb_bus *bus = ssb_gpio_get_bus(chip);
 151
 152         if (bus->bustype == SSB_BUSTYPE_SSB)
 153                 return ssb_mips_irq(bus->extif.dev) + 2;
 154         else
 155                 return -EINVAL;
 156 }
 157
 158 static int ssb_gpio_extif_init(struct ssb_bus *bus)
 159 {
 160         struct gpio_chip *chip = &bus->gpio;
 161
 162         chip->label             = "ssb_extif_gpio";
 163         chip->owner             = THIS_MODULE;
 164         chip->get               = ssb_gpio_extif_get_value;
 165         chip->set               = ssb_gpio_extif_set_value;
 166         chip->direction_input   = ssb_gpio_extif_direction_input;
 167         chip->direction_output  = ssb_gpio_extif_direction_output;
 168         chip->to_irq            = ssb_gpio_extif_to_irq;
 169         chip->ngpio             = 5;
 170         /* There is just one SoC in one device and its GPIO addresses should be
 171          * deterministic to address them more easily. The other buses could get
 172          * a random base number. */
 173         if (bus->bustype == SSB_BUSTYPE_SSB)
 174                 chip->base              = 0;
 175         else
 176                 chip->base              = -1;
 177
 178         return gpiochip_add(chip);
 179 }
 180
 181 #else
 182 static int ssb_gpio_extif_init(struct ssb_bus *bus)
 183 {
 184         return -ENOTSUPP;
 185 }
 186 #endif
 187
 188 int ssb_gpio_init(struct ssb_bus *bus)
 189 {
 190         if (ssb_chipco_available(&bus->chipco))
 191                 return ssb_gpio_chipco_init(bus);
 192         else if (ssb_extif_available(&bus->extif))
 193                 return ssb_gpio_extif_init(bus);
 194         else
 195                 SSB_WARN_ON(1);
 196
 197         return -1;
 198 }
 199
 200 int ssb_gpio_unregister(struct ssb_bus *bus)
 201 {
 202         if (ssb_chipco_available(&bus->chipco) ||
 203             ssb_extif_available(&bus->extif)) {
 204                 return gpiochip_remove(&bus->gpio);
 205         } else {
 206                 SSB_WARN_ON(1);
 207         }
 208
 209         return -1;
 210 }