target/linux/ramips/files/arch/mips/ralink/common/gpio.c

   1 /*
   2  * Ralink SoC specific GPIO support
   3  *
   4  * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 as published
   8  * by the Free Software Foundation.
   9  */
  10
  11 #include <linux/init.h>
  12 #include <linux/io.h>
  13
  14 #include <linux/gpio.h>
  15
  16 #include <ralink_soc.h>
  17
  18 #define GPIO0_REG_INT           0x00
  19 #define GPIO0_REG_EDGE          0x04
  20 #define GPIO0_REG_RENA          0x08
  21 #define GPIO0_REG_FENA          0x0c
  22 #define GPIO0_REG_DATA          0x20
  23 #define GPIO0_REG_DIR           0x24
  24 #define GPIO0_REG_POL           0x28
  25 #define GPIO0_REG_SET           0x2c
  26 #define GPIO0_REG_RESET         0x30
  27 #define GPIO0_REG_TOGGLE        0x34
  28
  29 #define GPIO1_REG_INT           0x38
  30 #define GPIO1_REG_EDGE          0x3c
  31 #define GPIO1_REG_RENA          0x40
  32 #define GPIO1_REG_FENA          0x44
  33 #define GPIO1_REG_DATA          0x48
  34 #define GPIO1_REG_DIR           0x4c
  35 #define GPIO1_REG_POL           0x50
  36 #define GPIO1_REG_SET           0x54
  37 #define GPIO1_REG_RESET         0x58
  38 #define GPIO1_REG_TOGGLE        0x5c
  39
  40 #define GPIO2_REG_INT           0x60
  41 #define GPIO2_REG_EDGE          0x64
  42 #define GPIO2_REG_RENA          0x68
  43 #define GPIO2_REG_FENA          0x6c
  44 #define GPIO2_REG_DATA          0x70
  45 #define GPIO2_REG_DIR           0x74
  46 #define GPIO2_REG_POL           0x78
  47 #define GPIO2_REG_SET           0x7c
  48 #define GPIO2_REG_RESET         0x80
  49 #define GPIO2_REG_TOGGLE        0x84
  50
  51 enum ramips_pio_reg {
  52         RAMIPS_GPIO_REG_INT,            /* Interrupt status */
  53         RAMIPS_GPIO_REG_EDGE,
  54         RAMIPS_GPIO_REG_RENA,
  55         RAMIPS_GPIO_REG_DATA,
  56         RAMIPS_GPIO_REG_DIR,            /* Direction, 0:in, 1: out */
  57         RAMIPS_GPIO_REG_POL,            /* Polarity, 0: normal, 1: invert */
  58         RAMIPS_GPIO_REG_SET,
  59         RAMIPS_GPIO_REG_RESET,
  60         RAMIPS_GPIO_REG_TOGGLE,
  61         RAMIPS_GPIO_REG_MAX
  62 };
  63
  64 struct ramips_gpio_chip {
  65         struct gpio_chip        chip;
  66         u8                      regs[RAMIPS_GPIO_REG_MAX];
  67 };
  68
  69 static void __iomem *ramips_gpio_base;
  70
  71 static inline struct ramips_gpio_chip *to_ramips_gpio(struct gpio_chip *chip)
  72 {
  73         struct ramips_gpio_chip *rg;
  74
  75         rg = container_of(chip, struct ramips_gpio_chip, chip);
  76         return rg;
  77 }
  78
  79 static inline void ramips_gpio_wr(struct ramips_gpio_chip *rg, u8 reg, u32 val)
  80 {
  81         __raw_writel(val, ramips_gpio_base + rg->regs[reg]);
  82 }
  83
  84 static inline u32 ramips_gpio_rr(struct ramips_gpio_chip *rg, u8 reg)
  85 {
  86         return __raw_readl(ramips_gpio_base + rg->regs[reg]);
  87 }
  88
  89 static int ramips_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
  90 {
  91         struct ramips_gpio_chip *rg = to_ramips_gpio(chip);
  92         u32 t;
  93
  94         t = ramips_gpio_rr(rg, RAMIPS_GPIO_REG_DIR);
  95         t &= ~(1 << offset);
  96         ramips_gpio_wr(rg, RAMIPS_GPIO_REG_DIR, t);
  97
  98         return 0;
  99 }
 100
 101 static int ramips_gpio_direction_output(struct gpio_chip *chip,
 102                                         unsigned offset, int value)
 103 {
 104         struct ramips_gpio_chip *rg = to_ramips_gpio(chip);
 105         u32 reg;
 106         u32 t;
 107
 108         reg = (value) ? RAMIPS_GPIO_REG_SET : RAMIPS_GPIO_REG_RESET;
 109         ramips_gpio_wr(rg, reg, 1 << offset);
 110
 111         t = ramips_gpio_rr(rg, RAMIPS_GPIO_REG_DIR);
 112         t |= 1 << offset;
 113         ramips_gpio_wr(rg, RAMIPS_GPIO_REG_DIR, t);
 114
 115         return 0;
 116 }
 117
 118 static void ramips_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 119 {
 120         struct ramips_gpio_chip *rg = to_ramips_gpio(chip);
 121         u32 reg;
 122
 123         reg = (value) ? RAMIPS_GPIO_REG_SET : RAMIPS_GPIO_REG_RESET;
 124         ramips_gpio_wr(rg, reg, 1 << offset);
 125 }
 126
 127 static int ramips_gpio_get(struct gpio_chip *chip, unsigned offset)
 128 {
 129         struct ramips_gpio_chip *rg = to_ramips_gpio(chip);
 130         u32 t;
 131
 132         t = ramips_gpio_rr(rg, RAMIPS_GPIO_REG_DATA);
 133         return (t & (1 << offset));
 134 }
 135
 136 static struct ramips_gpio_chip ramips_gpio_chip0 = {
 137         .chip = {
 138                 .label                  = "ramips-gpio0",
 139                 .direction_input        = ramips_gpio_direction_input,
 140                 .direction_output       = ramips_gpio_direction_output,
 141                 .get                    = ramips_gpio_get,
 142                 .set                    = ramips_gpio_set,
 143                 .base                   = 0,
 144                 .ngpio                  = RALINK_SOC_GPIO0_COUNT,
 145         },
 146         .regs = {
 147                 [RAMIPS_GPIO_REG_INT]   = GPIO0_REG_INT,
 148                 [RAMIPS_GPIO_REG_EDGE]  = GPIO0_REG_EDGE,
 149                 [RAMIPS_GPIO_REG_RENA]  = GPIO0_REG_RENA,
 150                 [RAMIPS_GPIO_REG_DATA]  = GPIO0_REG_DATA,
 151                 [RAMIPS_GPIO_REG_DIR]   = GPIO0_REG_DIR,
 152                 [RAMIPS_GPIO_REG_POL]   = GPIO0_REG_POL,
 153                 [RAMIPS_GPIO_REG_SET]   = GPIO0_REG_SET,
 154                 [RAMIPS_GPIO_REG_RESET] = GPIO0_REG_RESET,
 155                 [RAMIPS_GPIO_REG_TOGGLE] = GPIO0_REG_TOGGLE,
 156         },
 157 };
 158
 159 static struct ramips_gpio_chip ramips_gpio_chip1 = {
 160         .chip = {
 161                 .label                  = "ramips-gpio1",
 162                 .direction_input        = ramips_gpio_direction_input,
 163                 .direction_output       = ramips_gpio_direction_output,
 164                 .get                    = ramips_gpio_get,
 165                 .set                    = ramips_gpio_set,
 166                 .base                   = 32,
 167                 .ngpio                  = RALINK_SOC_GPIO1_COUNT,
 168         },
 169         .regs = {
 170                 [RAMIPS_GPIO_REG_INT]   = GPIO1_REG_INT,
 171                 [RAMIPS_GPIO_REG_EDGE]  = GPIO1_REG_EDGE,
 172                 [RAMIPS_GPIO_REG_RENA]  = GPIO1_REG_RENA,
 173                 [RAMIPS_GPIO_REG_DATA]  = GPIO1_REG_DATA,
 174                 [RAMIPS_GPIO_REG_DIR]   = GPIO1_REG_DIR,
 175                 [RAMIPS_GPIO_REG_POL]   = GPIO1_REG_POL,
 176                 [RAMIPS_GPIO_REG_SET]   = GPIO1_REG_SET,
 177                 [RAMIPS_GPIO_REG_RESET] = GPIO1_REG_RESET,
 178                 [RAMIPS_GPIO_REG_TOGGLE] = GPIO1_REG_TOGGLE,
 179         },
 180 };
 181
 182 static struct ramips_gpio_chip ramips_gpio_chip2 = {
 183         .chip = {
 184                 .label                  = "ramips-gpio2",
 185                 .direction_input        = ramips_gpio_direction_input,
 186                 .direction_output       = ramips_gpio_direction_output,
 187                 .get                    = ramips_gpio_get,
 188                 .set                    = ramips_gpio_set,
 189                 .base                   = 64,
 190                 .ngpio                  = RALINK_SOC_GPIO2_COUNT,
 191         },
 192         .regs = {
 193                 [RAMIPS_GPIO_REG_INT]   = GPIO2_REG_INT,
 194                 [RAMIPS_GPIO_REG_EDGE]  = GPIO2_REG_EDGE,
 195                 [RAMIPS_GPIO_REG_RENA]  = GPIO2_REG_RENA,
 196                 [RAMIPS_GPIO_REG_DATA]  = GPIO2_REG_DATA,
 197                 [RAMIPS_GPIO_REG_DIR]   = GPIO2_REG_DIR,
 198                 [RAMIPS_GPIO_REG_POL]   = GPIO2_REG_POL,
 199                 [RAMIPS_GPIO_REG_SET]   = GPIO2_REG_SET,
 200                 [RAMIPS_GPIO_REG_RESET] = GPIO2_REG_RESET,
 201                 [RAMIPS_GPIO_REG_TOGGLE] = GPIO2_REG_TOGGLE,
 202         },
 203 };
 204
 205 static __init void ramips_gpio_chip_add(struct ramips_gpio_chip *rg)
 206 {
 207         /* set polarity to low for all lines */
 208         ramips_gpio_wr(rg, RAMIPS_GPIO_REG_POL, 0);
 209
 210         gpiochip_add(&rg->chip);
 211 }
 212
 213 __init int ramips_gpio_init(void)
 214 {
 215         ramips_gpio_base = ioremap_nocache(RALINK_SOC_GPIO_BASE, PAGE_SIZE);
 216
 217         ramips_gpio_chip_add(&ramips_gpio_chip0);
 218         ramips_gpio_chip_add(&ramips_gpio_chip1);
 219         ramips_gpio_chip_add(&ramips_gpio_chip2);
 220
 221         return 0;
 222 }