arch/arm/mach-pxa/mfp-pxa2xx.c

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