drivers/pinctrl/sh-pfc/gpio.c

   1 /*
   2  * SuperH Pin Function Controller GPIO driver.
   3  *
   4  * Copyright (C) 2008 Magnus Damm
   5  * Copyright (C) 2009 - 2012 Paul Mundt
   6  *
   7  * This file is subject to the terms and conditions of the GNU General Public
   8  * License.  See the file "COPYING" in the main directory of this archive
   9  * for more details.
  10  */
  11
  12 #define pr_fmt(fmt) KBUILD_MODNAME " gpio: " fmt
  13
  14 #include <linux/device.h>
  15 #include <linux/gpio.h>
  16 #include <linux/init.h>
  17 #include <linux/module.h>
  18 #include <linux/pinctrl/consumer.h>
  19 #include <linux/slab.h>
  20 #include <linux/spinlock.h>
  21
  22 #include "core.h"
  23
  24 struct sh_pfc_chip {
  25         struct sh_pfc           *pfc;
  26         struct gpio_chip        gpio_chip;
  27 };
  28
  29 static struct sh_pfc_chip *gpio_to_pfc_chip(struct gpio_chip *gc)
  30 {
  31         return container_of(gc, struct sh_pfc_chip, gpio_chip);
  32 }
  33
  34 static struct sh_pfc *gpio_to_pfc(struct gpio_chip *gc)
  35 {
  36         return gpio_to_pfc_chip(gc)->pfc;
  37 }
  38
  39 static int sh_gpio_request(struct gpio_chip *gc, unsigned offset)
  40 {
  41         return pinctrl_request_gpio(offset);
  42 }
  43
  44 static void sh_gpio_free(struct gpio_chip *gc, unsigned offset)
  45 {
  46         pinctrl_free_gpio(offset);
  47 }
  48
  49 static void sh_gpio_set_value(struct sh_pfc *pfc, unsigned gpio, int value)
  50 {
  51         struct pinmux_data_reg *dr = NULL;
  52         int bit = 0;
  53
  54         if (sh_pfc_get_data_reg(pfc, gpio, &dr, &bit) != 0)
  55                 BUG();
  56         else
  57                 sh_pfc_write_bit(dr, bit, value);
  58 }
  59
  60 static int sh_gpio_get_value(struct sh_pfc *pfc, unsigned gpio)
  61 {
  62         struct pinmux_data_reg *dr = NULL;
  63         int bit = 0;
  64
  65         if (sh_pfc_get_data_reg(pfc, gpio, &dr, &bit) != 0)
  66                 return -EINVAL;
  67
  68         return sh_pfc_read_bit(dr, bit);
  69 }
  70
  71 static int sh_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
  72 {
  73         return pinctrl_gpio_direction_input(offset);
  74 }
  75
  76 static int sh_gpio_direction_output(struct gpio_chip *gc, unsigned offset,
  77                                     int value)
  78 {
  79         sh_gpio_set_value(gpio_to_pfc(gc), offset, value);
  80
  81         return pinctrl_gpio_direction_output(offset);
  82 }
  83
  84 static int sh_gpio_get(struct gpio_chip *gc, unsigned offset)
  85 {
  86         return sh_gpio_get_value(gpio_to_pfc(gc), offset);
  87 }
  88
  89 static void sh_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
  90 {
  91         sh_gpio_set_value(gpio_to_pfc(gc), offset, value);
  92 }
  93
  94 static int sh_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
  95 {
  96         struct sh_pfc *pfc = gpio_to_pfc(gc);
  97         pinmux_enum_t enum_id;
  98         pinmux_enum_t *enum_ids;
  99         int i, k, pos;
 100
 101         pos = 0;
 102         enum_id = 0;
 103         while (1) {
 104                 pos = sh_pfc_gpio_to_enum(pfc, offset, pos, &enum_id);
 105                 if (pos <= 0 || !enum_id)
 106                         break;
 107
 108                 for (i = 0; i < pfc->info->gpio_irq_size; i++) {
 109                         enum_ids = pfc->info->gpio_irq[i].enum_ids;
 110                         for (k = 0; enum_ids[k]; k++) {
 111                                 if (enum_ids[k] == enum_id)
 112                                         return pfc->info->gpio_irq[i].irq;
 113                         }
 114                 }
 115         }
 116
 117         return -ENOSYS;
 118 }
 119
 120 static void sh_pfc_gpio_setup(struct sh_pfc_chip *chip)
 121 {
 122         struct sh_pfc *pfc = chip->pfc;
 123         struct gpio_chip *gc = &chip->gpio_chip;
 124
 125         gc->request = sh_gpio_request;
 126         gc->free = sh_gpio_free;
 127         gc->direction_input = sh_gpio_direction_input;
 128         gc->get = sh_gpio_get;
 129         gc->direction_output = sh_gpio_direction_output;
 130         gc->set = sh_gpio_set;
 131         gc->to_irq = sh_gpio_to_irq;
 132
 133         WARN_ON(pfc->info->first_gpio != 0); /* needs testing */
 134
 135         gc->label = pfc->info->name;
 136         gc->owner = THIS_MODULE;
 137         gc->base = pfc->info->first_gpio;
 138         gc->ngpio = (pfc->info->last_gpio - pfc->info->first_gpio) + 1;
 139 }
 140
 141 int sh_pfc_register_gpiochip(struct sh_pfc *pfc)
 142 {
 143         struct sh_pfc_chip *chip;
 144         int ret;
 145
 146         chip = devm_kzalloc(pfc->dev, sizeof(*chip), GFP_KERNEL);
 147         if (unlikely(!chip))
 148                 return -ENOMEM;
 149
 150         chip->pfc = pfc;
 151
 152         sh_pfc_gpio_setup(chip);
 153
 154         ret = gpiochip_add(&chip->gpio_chip);
 155         if (unlikely(ret < 0))
 156                 return ret;
 157
 158         pfc->gpio = chip;
 159
 160         pr_info("%s handling gpio %d -> %d\n",
 161                 pfc->info->name, pfc->info->first_gpio,
 162                 pfc->info->last_gpio);
 163
 164         return 0;
 165 }
 166
 167 int sh_pfc_unregister_gpiochip(struct sh_pfc *pfc)
 168 {
 169         struct sh_pfc_chip *chip = pfc->gpio;
 170         int ret;
 171
 172         ret = gpiochip_remove(&chip->gpio_chip);
 173         if (unlikely(ret < 0))
 174                 return ret;
 175
 176         pfc->gpio = NULL;
 177         return 0;
 178 }