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
  19 #include <mach/common.h>
  20 #include <mach/tnetv107x.h>
  21
  22 struct tnetv107x_gpio_regs {
  23         u32     idver;
  24         u32     data_in[3];
  25         u32     data_out[3];
  26         u32     direction[3];
  27         u32     enable[3];
  28 };
  29
  30 #define gpio_reg_index(gpio)    ((gpio) >> 5)
  31 #define gpio_reg_bit(gpio)      BIT((gpio) & 0x1f)
  32
  33 #define gpio_reg_rmw(reg, mask, val)    \
  34         __raw_writel((__raw_readl(reg) & ~(mask)) | (val), (reg))
  35
  36 #define gpio_reg_set_bit(reg, gpio)     \
  37         gpio_reg_rmw((reg) + gpio_reg_index(gpio), 0, gpio_reg_bit(gpio))
  38
  39 #define gpio_reg_clear_bit(reg, gpio)   \
  40         gpio_reg_rmw((reg) + gpio_reg_index(gpio), gpio_reg_bit(gpio), 0)
  41
  42 #define gpio_reg_get_bit(reg, gpio)     \
  43         (__raw_readl((reg) + gpio_reg_index(gpio)) & gpio_reg_bit(gpio))
  44
  45 #define chip2controller(chip)           \
  46         container_of(chip, struct davinci_gpio_controller, chip)
  47
  48 #define TNETV107X_GPIO_CTLRS    DIV_ROUND_UP(TNETV107X_N_GPIO, 32)
  49
  50 static struct davinci_gpio_controller chips[TNETV107X_GPIO_CTLRS];
  51
  52 static int tnetv107x_gpio_request(struct gpio_chip *chip, unsigned offset)
  53 {
  54         struct davinci_gpio_controller *ctlr = chip2controller(chip);
  55         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
  56         unsigned gpio = chip->base + offset;
  57         unsigned long flags;
  58
  59         spin_lock_irqsave(&ctlr->lock, flags);
  60
  61         gpio_reg_set_bit(regs->enable, gpio);
  62
  63         spin_unlock_irqrestore(&ctlr->lock, flags);
  64
  65         return 0;
  66 }
  67
  68 static void tnetv107x_gpio_free(struct gpio_chip *chip, unsigned offset)
  69 {
  70         struct davinci_gpio_controller *ctlr = chip2controller(chip);
  71         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
  72         unsigned gpio = chip->base + offset;
  73         unsigned long flags;
  74
  75         spin_lock_irqsave(&ctlr->lock, flags);
  76
  77         gpio_reg_clear_bit(regs->enable, gpio);
  78
  79         spin_unlock_irqrestore(&ctlr->lock, flags);
  80 }
  81
  82 static int tnetv107x_gpio_dir_in(struct gpio_chip *chip, unsigned offset)
  83 {
  84         struct davinci_gpio_controller *ctlr = chip2controller(chip);
  85         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
  86         unsigned gpio = chip->base + offset;
  87         unsigned long flags;
  88
  89         spin_lock_irqsave(&ctlr->lock, flags);
  90
  91         gpio_reg_set_bit(regs->direction, gpio);
  92
  93         spin_unlock_irqrestore(&ctlr->lock, flags);
  94
  95         return 0;
  96 }
  97
  98 static int tnetv107x_gpio_dir_out(struct gpio_chip *chip,
  99                 unsigned offset, int value)
 100 {
 101         struct davinci_gpio_controller *ctlr = chip2controller(chip);
 102         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
 103         unsigned gpio = chip->base + offset;
 104         unsigned long flags;
 105
 106         spin_lock_irqsave(&ctlr->lock, flags);
 107
 108         if (value)
 109                 gpio_reg_set_bit(regs->data_out, gpio);
 110         else
 111                 gpio_reg_clear_bit(regs->data_out, gpio);
 112
 113         gpio_reg_clear_bit(regs->direction, gpio);
 114
 115         spin_unlock_irqrestore(&ctlr->lock, flags);
 116
 117         return 0;
 118 }
 119
 120 static int tnetv107x_gpio_get(struct gpio_chip *chip, unsigned offset)
 121 {
 122         struct davinci_gpio_controller *ctlr = chip2controller(chip);
 123         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
 124         unsigned gpio = chip->base + offset;
 125         int ret;
 126
 127         ret = gpio_reg_get_bit(regs->data_in, gpio);
 128
 129         return ret ? 1 : 0;
 130 }
 131
 132 static void tnetv107x_gpio_set(struct gpio_chip *chip,
 133                 unsigned offset, int value)
 134 {
 135         struct davinci_gpio_controller *ctlr = chip2controller(chip);
 136         struct tnetv107x_gpio_regs __iomem *regs = ctlr->regs;
 137         unsigned gpio = chip->base + offset;
 138         unsigned long flags;
 139
 140         spin_lock_irqsave(&ctlr->lock, flags);
 141
 142         if (value)
 143                 gpio_reg_set_bit(regs->data_out, gpio);
 144         else
 145                 gpio_reg_clear_bit(regs->data_out, gpio);
 146
 147         spin_unlock_irqrestore(&ctlr->lock, flags);
 148 }
 149
 150 static int __init tnetv107x_gpio_setup(void)
 151 {
 152         int i, base;
 153         unsigned ngpio;
 154         struct davinci_soc_info *soc_info = &davinci_soc_info;
 155         struct tnetv107x_gpio_regs *regs;
 156         struct davinci_gpio_controller *ctlr;
 157
 158         if (soc_info->gpio_type != GPIO_TYPE_TNETV107X)
 159                 return 0;
 160
 161         ngpio = soc_info->gpio_num;
 162         if (ngpio == 0) {
 163                 pr_err("GPIO setup:  how many GPIOs?\n");
 164                 return -EINVAL;
 165         }
 166
 167         if (WARN_ON(TNETV107X_N_GPIO < ngpio))
 168                 ngpio = TNETV107X_N_GPIO;
 169
 170         regs = ioremap(soc_info->gpio_base, SZ_4K);
 171         if (WARN_ON(!regs))
 172                 return -EINVAL;
 173
 174         for (i = 0, base = 0; base < ngpio; i++, base += 32) {
 175                 ctlr = &chips[i];
 176
 177                 ctlr->chip.label        = "tnetv107x";
 178                 ctlr->chip.can_sleep    = 0;
 179                 ctlr->chip.base         = base;
 180                 ctlr->chip.ngpio        = ngpio - base;
 181                 if (ctlr->chip.ngpio > 32)
 182                         ctlr->chip.ngpio = 32;
 183
 184                 ctlr->chip.request              = tnetv107x_gpio_request;
 185                 ctlr->chip.free                 = tnetv107x_gpio_free;
 186                 ctlr->chip.direction_input      = tnetv107x_gpio_dir_in;
 187                 ctlr->chip.get                  = tnetv107x_gpio_get;
 188                 ctlr->chip.direction_output     = tnetv107x_gpio_dir_out;
 189                 ctlr->chip.set                  = tnetv107x_gpio_set;
 190
 191                 spin_lock_init(&ctlr->lock);
 192
 193                 ctlr->regs      = regs;
 194                 ctlr->set_data  = &regs->data_out[i];
 195                 ctlr->clr_data  = &regs->data_out[i];
 196                 ctlr->in_data   = &regs->data_in[i];
 197
 198                 gpiochip_add(&ctlr->chip);
 199         }
 200
 201         soc_info->gpio_ctlrs = chips;
 202         soc_info->gpio_ctlrs_num = DIV_ROUND_UP(ngpio, 32);
 203         return 0;
 204 }
 205 pure_initcall(tnetv107x_gpio_setup);