linux/arch/mips/ar7/gpio.c
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   1/*
   2 * Copyright (C) 2007 Felix Fietkau <nbd@openwrt.org>
   3 * Copyright (C) 2007 Eugene Konev <ejka@openwrt.org>
   4 * Copyright (C) 2009-2010 Florian Fainelli <florian@openwrt.org>
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, write to the Free Software
  18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19 */
  20
  21#include <linux/module.h>
  22#include <linux/gpio.h>
  23
  24#include <asm/mach-ar7/gpio.h>
  25
  26struct ar7_gpio_chip {
  27        void __iomem            *regs;
  28        struct gpio_chip        chip;
  29};
  30
  31static int ar7_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
  32{
  33        struct ar7_gpio_chip *gpch =
  34                                container_of(chip, struct ar7_gpio_chip, chip);
  35        void __iomem *gpio_in = gpch->regs + AR7_GPIO_INPUT;
  36
  37        return readl(gpio_in) & (1 << gpio);
  38}
  39
  40static int titan_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
  41{
  42        struct ar7_gpio_chip *gpch =
  43                                container_of(chip, struct ar7_gpio_chip, chip);
  44        void __iomem *gpio_in0 = gpch->regs + TITAN_GPIO_INPUT_0;
  45        void __iomem *gpio_in1 = gpch->regs + TITAN_GPIO_INPUT_1;
  46
  47        return readl(gpio >> 5 ? gpio_in1 : gpio_in0) & (1 << (gpio & 0x1f));
  48}
  49
  50static void ar7_gpio_set_value(struct gpio_chip *chip,
  51                                unsigned gpio, int value)
  52{
  53        struct ar7_gpio_chip *gpch =
  54                                container_of(chip, struct ar7_gpio_chip, chip);
  55        void __iomem *gpio_out = gpch->regs + AR7_GPIO_OUTPUT;
  56        unsigned tmp;
  57
  58        tmp = readl(gpio_out) & ~(1 << gpio);
  59        if (value)
  60                tmp |= 1 << gpio;
  61        writel(tmp, gpio_out);
  62}
  63
  64static void titan_gpio_set_value(struct gpio_chip *chip,
  65                                unsigned gpio, int value)
  66{
  67        struct ar7_gpio_chip *gpch =
  68                                container_of(chip, struct ar7_gpio_chip, chip);
  69        void __iomem *gpio_out0 = gpch->regs + TITAN_GPIO_OUTPUT_0;
  70        void __iomem *gpio_out1 = gpch->regs + TITAN_GPIO_OUTPUT_1;
  71        unsigned tmp;
  72
  73        tmp = readl(gpio >> 5 ? gpio_out1 : gpio_out0) & ~(1 << (gpio & 0x1f));
  74        if (value)
  75                tmp |= 1 << (gpio & 0x1f);
  76        writel(tmp, gpio >> 5 ? gpio_out1 : gpio_out0);
  77}
  78
  79static int ar7_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
  80{
  81        struct ar7_gpio_chip *gpch =
  82                                container_of(chip, struct ar7_gpio_chip, chip);
  83        void __iomem *gpio_dir = gpch->regs + AR7_GPIO_DIR;
  84
  85        writel(readl(gpio_dir) | (1 << gpio), gpio_dir);
  86
  87        return 0;
  88}
  89
  90static int titan_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
  91{
  92        struct ar7_gpio_chip *gpch =
  93                                container_of(chip, struct ar7_gpio_chip, chip);
  94        void __iomem *gpio_dir0 = gpch->regs + TITAN_GPIO_DIR_0;
  95        void __iomem *gpio_dir1 = gpch->regs + TITAN_GPIO_DIR_1;
  96
  97        if (gpio >= TITAN_GPIO_MAX)
  98                return -EINVAL;
  99
 100        writel(readl(gpio >> 5 ? gpio_dir1 : gpio_dir0) | (1 << (gpio & 0x1f)),
 101                        gpio >> 5 ? gpio_dir1 : gpio_dir0);
 102        return 0;
 103}
 104
 105static int ar7_gpio_direction_output(struct gpio_chip *chip,
 106                                        unsigned gpio, int value)
 107{
 108        struct ar7_gpio_chip *gpch =
 109                                container_of(chip, struct ar7_gpio_chip, chip);
 110        void __iomem *gpio_dir = gpch->regs + AR7_GPIO_DIR;
 111
 112        ar7_gpio_set_value(chip, gpio, value);
 113        writel(readl(gpio_dir) & ~(1 << gpio), gpio_dir);
 114
 115        return 0;
 116}
 117
 118static int titan_gpio_direction_output(struct gpio_chip *chip,
 119                                        unsigned gpio, int value)
 120{
 121        struct ar7_gpio_chip *gpch =
 122                                container_of(chip, struct ar7_gpio_chip, chip);
 123        void __iomem *gpio_dir0 = gpch->regs + TITAN_GPIO_DIR_0;
 124        void __iomem *gpio_dir1 = gpch->regs + TITAN_GPIO_DIR_1;
 125
 126        if (gpio >= TITAN_GPIO_MAX)
 127                return -EINVAL;
 128
 129        titan_gpio_set_value(chip, gpio, value);
 130        writel(readl(gpio >> 5 ? gpio_dir1 : gpio_dir0) & ~(1 <<
 131                (gpio & 0x1f)), gpio >> 5 ? gpio_dir1 : gpio_dir0);
 132
 133        return 0;
 134}
 135
 136static struct ar7_gpio_chip ar7_gpio_chip = {
 137        .chip = {
 138                .label                  = "ar7-gpio",
 139                .direction_input        = ar7_gpio_direction_input,
 140                .direction_output       = ar7_gpio_direction_output,
 141                .set                    = ar7_gpio_set_value,
 142                .get                    = ar7_gpio_get_value,
 143                .base                   = 0,
 144                .ngpio                  = AR7_GPIO_MAX,
 145        }
 146};
 147
 148static struct ar7_gpio_chip titan_gpio_chip = {
 149        .chip = {
 150                .label                  = "titan-gpio",
 151                .direction_input        = titan_gpio_direction_input,
 152                .direction_output       = titan_gpio_direction_output,
 153                .set                    = titan_gpio_set_value,
 154                .get                    = titan_gpio_get_value,
 155                .base                   = 0,
 156                .ngpio                  = TITAN_GPIO_MAX,
 157        }
 158};
 159
 160static inline int ar7_gpio_enable_ar7(unsigned gpio)
 161{
 162        void __iomem *gpio_en = ar7_gpio_chip.regs + AR7_GPIO_ENABLE;
 163
 164        writel(readl(gpio_en) | (1 << gpio), gpio_en);
 165
 166        return 0;
 167}
 168
 169static inline int ar7_gpio_enable_titan(unsigned gpio)
 170{
 171        void __iomem *gpio_en0 = titan_gpio_chip.regs  + TITAN_GPIO_ENBL_0;
 172        void __iomem *gpio_en1 = titan_gpio_chip.regs  + TITAN_GPIO_ENBL_1;
 173
 174        writel(readl(gpio >> 5 ? gpio_en1 : gpio_en0) | (1 << (gpio & 0x1f)),
 175                gpio >> 5 ? gpio_en1 : gpio_en0);
 176
 177        return 0;
 178}
 179
 180int ar7_gpio_enable(unsigned gpio)
 181{
 182        return ar7_is_titan() ? ar7_gpio_enable_titan(gpio) :
 183                                ar7_gpio_enable_ar7(gpio);
 184}
 185EXPORT_SYMBOL(ar7_gpio_enable);
 186
 187static inline int ar7_gpio_disable_ar7(unsigned gpio)
 188{
 189        void __iomem *gpio_en = ar7_gpio_chip.regs + AR7_GPIO_ENABLE;
 190
 191        writel(readl(gpio_en) & ~(1 << gpio), gpio_en);
 192
 193        return 0;
 194}
 195
 196static inline int ar7_gpio_disable_titan(unsigned gpio)
 197{
 198        void __iomem *gpio_en0 = titan_gpio_chip.regs + TITAN_GPIO_ENBL_0;
 199        void __iomem *gpio_en1 = titan_gpio_chip.regs + TITAN_GPIO_ENBL_1;
 200
 201        writel(readl(gpio >> 5 ? gpio_en1 : gpio_en0) & ~(1 << (gpio & 0x1f)),
 202                        gpio >> 5 ? gpio_en1 : gpio_en0);
 203
 204        return 0;
 205}
 206
 207int ar7_gpio_disable(unsigned gpio)
 208{
 209        return ar7_is_titan() ? ar7_gpio_disable_titan(gpio) :
 210                                ar7_gpio_disable_ar7(gpio);
 211}
 212EXPORT_SYMBOL(ar7_gpio_disable);
 213
 214struct titan_gpio_cfg {
 215        u32 reg;
 216        u32 shift;
 217        u32 func;
 218};
 219
 220static struct titan_gpio_cfg titan_gpio_table[] = {
 221        /* reg, start bit, mux value */
 222        {4, 24, 1},
 223        {4, 26, 1},
 224        {4, 28, 1},
 225        {4, 30, 1},
 226        {5, 6, 1},
 227        {5, 8, 1},
 228        {5, 10, 1},
 229        {5, 12, 1},
 230        {7, 14, 3},
 231        {7, 16, 3},
 232        {7, 18, 3},
 233        {7, 20, 3},
 234        {7, 22, 3},
 235        {7, 26, 3},
 236        {7, 28, 3},
 237        {7, 30, 3},
 238        {8, 0, 3},
 239        {8, 2, 3},
 240        {8, 4, 3},
 241        {8, 10, 3},
 242        {8, 14, 3},
 243        {8, 16, 3},
 244        {8, 18, 3},
 245        {8, 20, 3},
 246        {9, 8, 3},
 247        {9, 10, 3},
 248        {9, 12, 3},
 249        {9, 14, 3},
 250        {9, 18, 3},
 251        {9, 20, 3},
 252        {9, 24, 3},
 253        {9, 26, 3},
 254        {9, 28, 3},
 255        {9, 30, 3},
 256        {10, 0, 3},
 257        {10, 2, 3},
 258        {10, 8, 3},
 259        {10, 10, 3},
 260        {10, 12, 3},
 261        {10, 14, 3},
 262        {13, 12, 3},
 263        {13, 14, 3},
 264        {13, 16, 3},
 265        {13, 18, 3},
 266        {13, 24, 3},
 267        {13, 26, 3},
 268        {13, 28, 3},
 269        {13, 30, 3},
 270        {14, 2, 3},
 271        {14, 6, 3},
 272        {14, 8, 3},
 273        {14, 12, 3}
 274};
 275
 276static int titan_gpio_pinsel(unsigned gpio)
 277{
 278        struct titan_gpio_cfg gpio_cfg;
 279        u32 mux_status, pin_sel_reg, tmp;
 280        void __iomem *pin_sel = (void __iomem *)KSEG1ADDR(AR7_REGS_PINSEL);
 281
 282        if (gpio >= ARRAY_SIZE(titan_gpio_table))
 283                return -EINVAL;
 284
 285        gpio_cfg = titan_gpio_table[gpio];
 286        pin_sel_reg = gpio_cfg.reg - 1;
 287
 288        mux_status = (readl(pin_sel + pin_sel_reg) >> gpio_cfg.shift) & 0x3;
 289
 290        /* Check the mux status */
 291        if (!((mux_status == 0) || (mux_status == gpio_cfg.func)))
 292                return 0;
 293
 294        /* Set the pin sel value */
 295        tmp = readl(pin_sel + pin_sel_reg);
 296        tmp |= ((gpio_cfg.func & 0x3) << gpio_cfg.shift);
 297        writel(tmp, pin_sel + pin_sel_reg);
 298
 299        return 0;
 300}
 301
 302/* Perform minimal Titan GPIO configuration */
 303static void titan_gpio_init(void)
 304{
 305        unsigned i;
 306
 307        for (i = 44; i < 48; i++) {
 308                titan_gpio_pinsel(i);
 309                ar7_gpio_enable_titan(i);
 310                titan_gpio_direction_input(&titan_gpio_chip.chip, i);
 311        }
 312}
 313
 314int __init ar7_gpio_init(void)
 315{
 316        int ret;
 317        struct ar7_gpio_chip *gpch;
 318        unsigned size;
 319
 320        if (!ar7_is_titan()) {
 321                gpch = &ar7_gpio_chip;
 322                size = 0x10;
 323        } else {
 324                gpch = &titan_gpio_chip;
 325                size = 0x1f;
 326        }
 327
 328        gpch->regs = ioremap_nocache(AR7_REGS_GPIO,
 329                                        AR7_REGS_GPIO + 0x10);
 330
 331        if (!gpch->regs) {
 332                printk(KERN_ERR "%s: failed to ioremap regs\n",
 333                                        gpch->chip.label);
 334                return -ENOMEM;
 335        }
 336
 337        ret = gpiochip_add(&gpch->chip);
 338        if (ret) {
 339                printk(KERN_ERR "%s: failed to add gpiochip\n",
 340                                        gpch->chip.label);
 341                return ret;
 342        }
 343        printk(KERN_INFO "%s: registered %d GPIOs\n",
 344                                gpch->chip.label, gpch->chip.ngpio);
 345
 346        if (ar7_is_titan())
 347                titan_gpio_init();
 348
 349        return ret;
 350}
 351