linux/arch/arm/mach-pxa/mfp-pxa2xx.c
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   1/*
   2 *  linux/arch/arm/mach-pxa/mfp-pxa2xx.c
   3 *
   4 *  PXA2xx pin mux configuration support
   5 *
   6 *  The GPIOs on PXA2xx can be configured as one of many alternate
   7 *  functions, this is by concept samilar to the MFP configuration
   8 *  on PXA3xx,  what's more important, the low power pin state and
   9 *  wakeup detection are also supported by the same framework.
  10 *
  11 *  This program is free software; you can redistribute it and/or modify
  12 *  it under the terms of the GNU General Public License version 2 as
  13 *  published by the Free Software Foundation.
  14 */
  15#include <linux/gpio.h>
  16#include <linux/gpio-pxa.h>
  17#include <linux/module.h>
  18#include <linux/kernel.h>
  19#include <linux/init.h>
  20#include <linux/io.h>
  21#include <linux/syscore_ops.h>
  22
  23#include <mach/pxa2xx-regs.h>
  24#include <mach/mfp-pxa2xx.h>
  25
  26#include "generic.h"
  27
  28#define PGSR(x)         __REG2(0x40F00020, (x) << 2)
  29#define __GAFR(u, x)    __REG2((u) ? 0x40E00058 : 0x40E00054, (x) << 3)
  30#define GAFR_L(x)       __GAFR(0, x)
  31#define GAFR_U(x)       __GAFR(1, x)
  32
  33#define BANK_OFF(n)     (((n) < 3) ? (n) << 2 : 0x100 + (((n) - 3) << 2))
  34#define GPLR(x)         __REG2(0x40E00000, BANK_OFF((x) >> 5))
  35#define GPDR(x)         __REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x0c)
  36#define GPSR(x)         __REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x18)
  37#define GPCR(x)         __REG2(0x40E00000, BANK_OFF((x) >> 5) + 0x24)
  38
  39#define PWER_WE35       (1 << 24)
  40
  41struct gpio_desc {
  42        unsigned        valid           : 1;
  43        unsigned        can_wakeup      : 1;
  44        unsigned        keypad_gpio     : 1;
  45        unsigned        dir_inverted    : 1;
  46        unsigned int    mask; /* bit mask in PWER or PKWR */
  47        unsigned int    mux_mask; /* bit mask of muxed gpio bits, 0 if no mux */
  48        unsigned long   config;
  49};
  50
  51static struct gpio_desc gpio_desc[MFP_PIN_GPIO127 + 1];
  52
  53static unsigned long gpdr_lpm[4];
  54
  55static int __mfp_config_gpio(unsigned gpio, unsigned long c)
  56{
  57        unsigned long gafr, mask = GPIO_bit(gpio);
  58        int bank = gpio_to_bank(gpio);
  59        int uorl = !!(gpio & 0x10); /* GAFRx_U or GAFRx_L ? */
  60        int shft = (gpio & 0xf) << 1;
  61        int fn = MFP_AF(c);
  62        int is_out = (c & MFP_DIR_OUT) ? 1 : 0;
  63
  64        if (fn > 3)
  65                return -EINVAL;
  66
  67        /* alternate function and direction at run-time */
  68        gafr = (uorl == 0) ? GAFR_L(bank) : GAFR_U(bank);
  69        gafr = (gafr & ~(0x3 << shft)) | (fn << shft);
  70
  71        if (uorl == 0)
  72                GAFR_L(bank) = gafr;
  73        else
  74                GAFR_U(bank) = gafr;
  75
  76        if (is_out ^ gpio_desc[gpio].dir_inverted)
  77                GPDR(gpio) |= mask;
  78        else
  79                GPDR(gpio) &= ~mask;
  80
  81        /* alternate function and direction at low power mode */
  82        switch (c & MFP_LPM_STATE_MASK) {
  83        case MFP_LPM_DRIVE_HIGH:
  84                PGSR(bank) |= mask;
  85                is_out = 1;
  86                break;
  87        case MFP_LPM_DRIVE_LOW:
  88                PGSR(bank) &= ~mask;
  89                is_out = 1;
  90                break;
  91        case MFP_LPM_INPUT:
  92        case MFP_LPM_DEFAULT:
  93                break;
  94        default:
  95                /* warning and fall through, treat as MFP_LPM_DEFAULT */
  96                pr_warning("%s: GPIO%d: unsupported low power mode\n",
  97                                __func__, gpio);
  98                break;
  99        }
 100
 101        if (is_out ^ gpio_desc[gpio].dir_inverted)
 102                gpdr_lpm[bank] |= mask;
 103        else
 104                gpdr_lpm[bank] &= ~mask;
 105
 106        /* give early warning if MFP_LPM_CAN_WAKEUP is set on the
 107         * configurations of those pins not able to wakeup
 108         */
 109        if ((c & MFP_LPM_CAN_WAKEUP) && !gpio_desc[gpio].can_wakeup) {
 110                pr_warning("%s: GPIO%d unable to wakeup\n",
 111                                __func__, gpio);
 112                return -EINVAL;
 113        }
 114
 115        if ((c & MFP_LPM_CAN_WAKEUP) && is_out) {
 116                pr_warning("%s: output GPIO%d unable to wakeup\n",
 117                                __func__, gpio);
 118                return -EINVAL;
 119        }
 120
 121        return 0;
 122}
 123
 124static inline int __mfp_validate(int mfp)
 125{
 126        int gpio = mfp_to_gpio(mfp);
 127
 128        if ((mfp > MFP_PIN_GPIO127) || !gpio_desc[gpio].valid) {
 129                pr_warning("%s: GPIO%d is invalid pin\n", __func__, gpio);
 130                return -1;
 131        }
 132
 133        return gpio;
 134}
 135
 136void pxa2xx_mfp_config(unsigned long *mfp_cfgs, int num)
 137{
 138        unsigned long flags;
 139        unsigned long *c;
 140        int i, gpio;
 141
 142        for (i = 0, c = mfp_cfgs; i < num; i++, c++) {
 143
 144                gpio = __mfp_validate(MFP_PIN(*c));
 145                if (gpio < 0)
 146                        continue;
 147
 148                local_irq_save(flags);
 149
 150                gpio_desc[gpio].config = *c;
 151                __mfp_config_gpio(gpio, *c);
 152
 153                local_irq_restore(flags);
 154        }
 155}
 156
 157void pxa2xx_mfp_set_lpm(int mfp, unsigned long lpm)
 158{
 159        unsigned long flags, c;
 160        int gpio;
 161
 162        gpio = __mfp_validate(mfp);
 163        if (gpio < 0)
 164                return;
 165
 166        local_irq_save(flags);
 167
 168        c = gpio_desc[gpio].config;
 169        c = (c & ~MFP_LPM_STATE_MASK) | lpm;
 170        __mfp_config_gpio(gpio, c);
 171
 172        local_irq_restore(flags);
 173}
 174
 175int gpio_set_wake(unsigned int gpio, unsigned int on)
 176{
 177        struct gpio_desc *d;
 178        unsigned long c, mux_taken;
 179
 180        if (gpio > mfp_to_gpio(MFP_PIN_GPIO127))
 181                return -EINVAL;
 182
 183        d = &gpio_desc[gpio];
 184        c = d->config;
 185
 186        if (!d->valid)
 187                return -EINVAL;
 188
 189        /* Allow keypad GPIOs to wakeup system when
 190         * configured as generic GPIOs.
 191         */
 192        if (d->keypad_gpio && (MFP_AF(d->config) == 0) &&
 193            (d->config & MFP_LPM_CAN_WAKEUP)) {
 194                if (on)
 195                        PKWR |= d->mask;
 196                else
 197                        PKWR &= ~d->mask;
 198                return 0;
 199        }
 200
 201        mux_taken = (PWER & d->mux_mask) & (~d->mask);
 202        if (on && mux_taken)
 203                return -EBUSY;
 204
 205        if (d->can_wakeup && (c & MFP_LPM_CAN_WAKEUP)) {
 206                if (on) {
 207                        PWER = (PWER & ~d->mux_mask) | d->mask;
 208
 209                        if (c & MFP_LPM_EDGE_RISE)
 210                                PRER |= d->mask;
 211                        else
 212                                PRER &= ~d->mask;
 213
 214                        if (c & MFP_LPM_EDGE_FALL)
 215                                PFER |= d->mask;
 216                        else
 217                                PFER &= ~d->mask;
 218                } else {
 219                        PWER &= ~d->mask;
 220                        PRER &= ~d->mask;
 221                        PFER &= ~d->mask;
 222                }
 223        }
 224        return 0;
 225}
 226
 227#ifdef CONFIG_PXA25x
 228static void __init pxa25x_mfp_init(void)
 229{
 230        int i;
 231
 232        /* running before pxa_gpio_probe() */
 233#ifdef CONFIG_CPU_PXA26x
 234        pxa_last_gpio = 89;
 235#else
 236        pxa_last_gpio = 84;
 237#endif
 238        for (i = 0; i <= pxa_last_gpio; i++)
 239                gpio_desc[i].valid = 1;
 240
 241        for (i = 0; i <= 15; i++) {
 242                gpio_desc[i].can_wakeup = 1;
 243                gpio_desc[i].mask = GPIO_bit(i);
 244        }
 245
 246        /* PXA26x has additional 4 GPIOs (86/87/88/89) which has the
 247         * direction bit inverted in GPDR2. See PXA26x DM 4.1.1.
 248         */
 249        for (i = 86; i <= pxa_last_gpio; i++)
 250                gpio_desc[i].dir_inverted = 1;
 251}
 252#else
 253static inline void pxa25x_mfp_init(void) {}
 254#endif /* CONFIG_PXA25x */
 255
 256#ifdef CONFIG_PXA27x
 257static int pxa27x_pkwr_gpio[] = {
 258        13, 16, 17, 34, 36, 37, 38, 39, 90, 91, 93, 94,
 259        95, 96, 97, 98, 99, 100, 101, 102
 260};
 261
 262int keypad_set_wake(unsigned int on)
 263{
 264        unsigned int i, gpio, mask = 0;
 265        struct gpio_desc *d;
 266
 267        for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
 268
 269                gpio = pxa27x_pkwr_gpio[i];
 270                d = &gpio_desc[gpio];
 271
 272                /* skip if configured as generic GPIO */
 273                if (MFP_AF(d->config) == 0)
 274                        continue;
 275
 276                if (d->config & MFP_LPM_CAN_WAKEUP)
 277                        mask |= gpio_desc[gpio].mask;
 278        }
 279
 280        if (on)
 281                PKWR |= mask;
 282        else
 283                PKWR &= ~mask;
 284        return 0;
 285}
 286
 287#define PWER_WEMUX2_GPIO38      (1 << 16)
 288#define PWER_WEMUX2_GPIO53      (2 << 16)
 289#define PWER_WEMUX2_GPIO40      (3 << 16)
 290#define PWER_WEMUX2_GPIO36      (4 << 16)
 291#define PWER_WEMUX2_MASK        (7 << 16)
 292#define PWER_WEMUX3_GPIO31      (1 << 19)
 293#define PWER_WEMUX3_GPIO113     (2 << 19)
 294#define PWER_WEMUX3_MASK        (3 << 19)
 295
 296#define INIT_GPIO_DESC_MUXED(mux, gpio)                         \
 297do {                                                            \
 298        gpio_desc[(gpio)].can_wakeup = 1;                       \
 299        gpio_desc[(gpio)].mask = PWER_ ## mux ## _GPIO ##gpio;  \
 300        gpio_desc[(gpio)].mux_mask = PWER_ ## mux ## _MASK;     \
 301} while (0)
 302
 303static void __init pxa27x_mfp_init(void)
 304{
 305        int i, gpio;
 306
 307        pxa_last_gpio = 120;    /* running before pxa_gpio_probe() */
 308        for (i = 0; i <= pxa_last_gpio; i++) {
 309                /* skip GPIO2, 5, 6, 7, 8, they are not
 310                 * valid pins allow configuration
 311                 */
 312                if (i == 2 || i == 5 || i == 6 || i == 7 || i == 8)
 313                        continue;
 314
 315                gpio_desc[i].valid = 1;
 316        }
 317
 318        /* Keypad GPIOs */
 319        for (i = 0; i < ARRAY_SIZE(pxa27x_pkwr_gpio); i++) {
 320                gpio = pxa27x_pkwr_gpio[i];
 321                gpio_desc[gpio].can_wakeup = 1;
 322                gpio_desc[gpio].keypad_gpio = 1;
 323                gpio_desc[gpio].mask = 1 << i;
 324        }
 325
 326        /* Overwrite GPIO13 as a PWER wakeup source */
 327        for (i = 0; i <= 15; i++) {
 328                /* skip GPIO2, 5, 6, 7, 8 */
 329                if (GPIO_bit(i) & 0x1e4)
 330                        continue;
 331
 332                gpio_desc[i].can_wakeup = 1;
 333                gpio_desc[i].mask = GPIO_bit(i);
 334        }
 335
 336        gpio_desc[35].can_wakeup = 1;
 337        gpio_desc[35].mask = PWER_WE35;
 338
 339        INIT_GPIO_DESC_MUXED(WEMUX3, 31);
 340        INIT_GPIO_DESC_MUXED(WEMUX3, 113);
 341        INIT_GPIO_DESC_MUXED(WEMUX2, 38);
 342        INIT_GPIO_DESC_MUXED(WEMUX2, 53);
 343        INIT_GPIO_DESC_MUXED(WEMUX2, 40);
 344        INIT_GPIO_DESC_MUXED(WEMUX2, 36);
 345}
 346#else
 347static inline void pxa27x_mfp_init(void) {}
 348#endif /* CONFIG_PXA27x */
 349
 350#ifdef CONFIG_PM
 351static unsigned long saved_gafr[2][4];
 352static unsigned long saved_gpdr[4];
 353static unsigned long saved_gplr[4];
 354static unsigned long saved_pgsr[4];
 355
 356static int pxa2xx_mfp_suspend(void)
 357{
 358        int i;
 359
 360        /* set corresponding PGSR bit of those marked MFP_LPM_KEEP_OUTPUT */
 361        for (i = 0; i < pxa_last_gpio; i++) {
 362                if ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
 363                    (GPDR(i) & GPIO_bit(i))) {
 364                        if (GPLR(i) & GPIO_bit(i))
 365                                PGSR(gpio_to_bank(i)) |= GPIO_bit(i);
 366                        else
 367                                PGSR(gpio_to_bank(i)) &= ~GPIO_bit(i);
 368                }
 369        }
 370
 371        for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
 372                saved_gafr[0][i] = GAFR_L(i);
 373                saved_gafr[1][i] = GAFR_U(i);
 374                saved_gpdr[i] = GPDR(i * 32);
 375                saved_gplr[i] = GPLR(i * 32);
 376                saved_pgsr[i] = PGSR(i);
 377
 378                GPSR(i * 32) = PGSR(i);
 379                GPCR(i * 32) = ~PGSR(i);
 380        }
 381
 382        /* set GPDR bits taking into account MFP_LPM_KEEP_OUTPUT */
 383        for (i = 0; i < pxa_last_gpio; i++) {
 384                if ((gpdr_lpm[gpio_to_bank(i)] & GPIO_bit(i)) ||
 385                    ((gpio_desc[i].config & MFP_LPM_KEEP_OUTPUT) &&
 386                     (saved_gpdr[gpio_to_bank(i)] & GPIO_bit(i))))
 387                        GPDR(i) |= GPIO_bit(i);
 388                else
 389                        GPDR(i) &= ~GPIO_bit(i);
 390        }
 391
 392        return 0;
 393}
 394
 395static void pxa2xx_mfp_resume(void)
 396{
 397        int i;
 398
 399        for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++) {
 400                GAFR_L(i) = saved_gafr[0][i];
 401                GAFR_U(i) = saved_gafr[1][i];
 402                GPSR(i * 32) = saved_gplr[i];
 403                GPCR(i * 32) = ~saved_gplr[i];
 404                GPDR(i * 32) = saved_gpdr[i];
 405                PGSR(i) = saved_pgsr[i];
 406        }
 407        PSSR = PSSR_RDH | PSSR_PH;
 408}
 409#else
 410#define pxa2xx_mfp_suspend      NULL
 411#define pxa2xx_mfp_resume       NULL
 412#endif
 413
 414struct syscore_ops pxa2xx_mfp_syscore_ops = {
 415        .suspend        = pxa2xx_mfp_suspend,
 416        .resume         = pxa2xx_mfp_resume,
 417};
 418
 419static int __init pxa2xx_mfp_init(void)
 420{
 421        int i;
 422
 423        if (!cpu_is_pxa2xx())
 424                return 0;
 425
 426        if (cpu_is_pxa25x())
 427                pxa25x_mfp_init();
 428
 429        if (cpu_is_pxa27x())
 430                pxa27x_mfp_init();
 431
 432        /* clear RDH bit to enable GPIO receivers after reset/sleep exit */
 433        PSSR = PSSR_RDH;
 434
 435        /* initialize gafr_run[], pgsr_lpm[] from existing values */
 436        for (i = 0; i <= gpio_to_bank(pxa_last_gpio); i++)
 437                gpdr_lpm[i] = GPDR(i * 32);
 438
 439        return 0;
 440}
 441postcore_initcall(pxa2xx_mfp_init);
 442