drivers/gpio/gpio-tnetv107x.c

   1 /*
   2  * Texas Instruments TNETV107X GPIO Controller
   3  *
   4  * Copyright (C) 2010 Texas Instruments
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation version 2.
   9  *
  10  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
  11  * kind, whether express or implied; without even the implied warranty
  12  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15 #include <linux/kernel.h>
  16 #include <linux/init.h>
  17 #include <linux/gpio.h>
  18 #include <linux/platform_data/gpio-davinci.h>
  19
  20 #include <mach/common.h>
  21 #include <mach/tnetv107x.h>
  22
  23 struct tnetv107x_gpio_regs {
  24         u32     idver;
  25         u32     data_in[3];
  26         u32     data_out[3];
  27         u32     direction[3];
  28         u32     enable[3];
  29 };
  30
  31 #define gpio_reg_index(gpio)    ((gpio) >> 5)
  32 #define gpio_reg_bit(gpio)      BIT((gpio) & 0x1f)
  33
  34 #define gpio_reg_rmw(reg, mask, val)    \
  35         __raw_writel((__raw_readl(reg) & ~(mask)) | (val), (reg))
  36
  37 #define gpio_reg_set_bit(reg, gpio)     \
  38         gpio_reg_rmw((reg) + gpio_reg_index(gpio), 0, gpio_reg_bit(gpio))
  39
  40 #define gpio_reg_clear_bit(reg, gpio)   \
  41         gpio_reg_rmw((reg) + gpio_reg_index(gpio), gpio_reg_bit(gpio), 0)
  42
  43 #define gpio_reg_get_bit(reg, gpio)     \
  44         (__raw_readl((reg) + gpio_reg_index(gpio)) & gpio_reg_bit(gpio))
  45
  46 #define chip2controller(chip)           \
  47         container_of(chip, struct davinci_gpio_controller, chip)
  48
  49 #define TNETV107X_GPIO_CTLRS    DIV_ROUND_UP(TNETV107X_N_GPIO, 32)
  50
  51 static struct davinci_gpio_controller chips[TNETV107X_GPIO_CTLRS];
  52
  53 static int tnetv107x_gpio_request(struct gpio_chip *chip, unsigned offset)
  54 {
  55         struct davinci_gpio_controller *ctlr = chip2controller(chip);
  56         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
  57         unsigned gpio = chip->base + offset;
  58         unsigned long flags;
  59
  60         spin_lock_irqsave(&ctlr->lock, flags);
  61
  62         gpio_reg_set_bit(regs->enable, gpio);
  63
  64         spin_unlock_irqrestore(&ctlr->lock, flags);
  65
  66         return 0;
  67 }
  68
  69 static void tnetv107x_gpio_free(struct gpio_chip *chip, unsigned offset)
  70 {
  71         struct davinci_gpio_controller *ctlr = chip2controller(chip);
  72         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
  73         unsigned gpio = chip->base + offset;
  74         unsigned long flags;
  75
  76         spin_lock_irqsave(&ctlr->lock, flags);
  77
  78         gpio_reg_clear_bit(regs->enable, gpio);
  79
  80         spin_unlock_irqrestore(&ctlr->lock, flags);
  81 }
  82
  83 static int tnetv107x_gpio_dir_in(struct gpio_chip *chip, unsigned offset)
  84 {
  85         struct davinci_gpio_controller *ctlr = chip2controller(chip);
  86         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
  87         unsigned gpio = chip->base + offset;
  88         unsigned long flags;
  89
  90         spin_lock_irqsave(&ctlr->lock, flags);
  91
  92         gpio_reg_set_bit(regs->direction, gpio);
  93
  94         spin_unlock_irqrestore(&ctlr->lock, flags);
  95
  96         return 0;
  97 }
  98
  99 static int tnetv107x_gpio_dir_out(struct gpio_chip *chip,
 100                 unsigned offset, int value)
 101 {
 102         struct davinci_gpio_controller *ctlr = chip2controller(chip);
 103         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
 104         unsigned gpio = chip->base + offset;
 105         unsigned long flags;
 106
 107         spin_lock_irqsave(&ctlr->lock, flags);
 108
 109         if (value)
 110                 gpio_reg_set_bit(regs->data_out, gpio);
 111         else
 112                 gpio_reg_clear_bit(regs->data_out, gpio);
 113
 114         gpio_reg_clear_bit(regs->direction, gpio);
 115
 116         spin_unlock_irqrestore(&ctlr->lock, flags);
 117
 118         return 0;
 119 }
 120
 121 static int tnetv107x_gpio_get(struct gpio_chip *chip, unsigned offset)
 122 {
 123         struct davinci_gpio_controller *ctlr = chip2controller(chip);
 124         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
 125         unsigned gpio = chip->base + offset;
 126         int ret;
 127
 128         ret = gpio_reg_get_bit(regs->data_in, gpio);
 129
 130         return ret ? 1 : 0;
 131 }
 132
 133 static void tnetv107x_gpio_set(struct gpio_chip *chip,
 134                 unsigned offset, int value)
 135 {
 136         struct davinci_gpio_controller *ctlr = chip2controller(chip);
 137         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
 138         unsigned gpio = chip->base + offset;
 139         unsigned long flags;
 140
 141         spin_lock_irqsave(&ctlr->lock, flags);
 142
 143         if (value)
 144                 gpio_reg_set_bit(regs->data_out, gpio);
 145         else
 146                 gpio_reg_clear_bit(regs->data_out, gpio);
 147
 148         spin_unlock_irqrestore(&ctlr->lock, flags);
 149 }
 150
 151 static int __init tnetv107x_gpio_setup(void)
 152 {
 153         int i, base;
 154         unsigned ngpio;
 155         struct davinci_soc_info *soc_info = &davinci_soc_info;
 156         struct tnetv107x_gpio_regs *regs;
 157         struct davinci_gpio_controller *ctlr;
 158
 159         if (soc_info->gpio_type != GPIO_TYPE_TNETV107X)
 160                 return 0;
 161
 162         ngpio = soc_info->gpio_num;
 163         if (ngpio == 0) {
 164                 pr_err("GPIO setup:  how many GPIOs?\n");
 165                 return -EINVAL;
 166         }
 167
 168         if (WARN_ON(TNETV107X_N_GPIO < ngpio))
 169                 ngpio = TNETV107X_N_GPIO;
 170
 171         regs = ioremap(soc_info->gpio_base, SZ_4K);
 172         if (WARN_ON(!regs))
 173                 return -EINVAL;
 174
 175         for (i = 0, base = 0; base < ngpio; i++, base += 32) {
 176                 ctlr = &chips[i];
 177
 178                 ctlr->chip.label        = "tnetv107x";
 179                 ctlr->chip.can_sleep    = false;
 180                 ctlr->chip.base         = base;
 181                 ctlr->chip.ngpio        = ngpio - base;
 182                 if (ctlr->chip.ngpio > 32)
 183                         ctlr->chip.ngpio = 32;
 184
 185                 ctlr->chip.request              = tnetv107x_gpio_request;
 186                 ctlr->chip.free                 = tnetv107x_gpio_free;
 187                 ctlr->chip.direction_input      = tnetv107x_gpio_dir_in;
 188                 ctlr->chip.get                  = tnetv107x_gpio_get;
 189                 ctlr->chip.direction_output     = tnetv107x_gpio_dir_out;
 190                 ctlr->chip.set                  = tnetv107x_gpio_set;
 191
 192                 spin_lock_init(&ctlr->lock);
 193
 194                 ctlr->regs      = regs;
 195                 ctlr->set_data  = &regs->data_out[i];
 196                 ctlr->clr_data  = &regs->data_out[i];
 197                 ctlr->in_data   = &regs->data_in[i];
 198
 199                 gpiochip_add(&ctlr->chip);
 200         }
 201
 202         soc_info->gpio_ctlrs = chips;
 203         soc_info->gpio_ctlrs_num = DIV_ROUND_UP(ngpio, 32);
 204         return 0;
 205 }
 206 pure_initcall(tnetv107x_gpio_setup);