arch/arm/mach-pnx4008/gpio.c

   1 /*
   2  * arch/arm/mach-pnx4008/gpio.c
   3  *
   4  * PNX4008 GPIO driver
   5  *
   6  * Author: Dmitry Chigirev <source@mvista.com>
   7  *
   8  * Based on reference code by Iwo Mergler and Z.Tabaaloute from Philips:
   9  * Copyright (c) 2005 Koninklijke Philips Electronics N.V.
  10  *
  11  * 2005 (c) MontaVista Software, Inc. This file is licensed under
  12  * the terms of the GNU General Public License version 2. This program
  13  * is licensed "as is" without any warranty of any kind, whether express
  14  * or implied.
  15  */
  16
  17 #include <linux/types.h>
  18 #include <linux/kernel.h>
  19 #include <linux/module.h>
  20 #include <linux/io.h>
  21 #include <mach/hardware.h>
  22 #include <mach/platform.h>
  23 #include <mach/gpio.h>
  24
  25 /* register definitions */
  26 #define PIO_VA_BASE     IO_ADDRESS(PNX4008_PIO_BASE)
  27
  28 #define PIO_INP_STATE   (0x00U)
  29 #define PIO_OUTP_SET    (0x04U)
  30 #define PIO_OUTP_CLR    (0x08U)
  31 #define PIO_OUTP_STATE  (0x0CU)
  32 #define PIO_DRV_SET     (0x10U)
  33 #define PIO_DRV_CLR     (0x14U)
  34 #define PIO_DRV_STATE   (0x18U)
  35 #define PIO_SDINP_STATE (0x1CU)
  36 #define PIO_SDOUTP_SET  (0x20U)
  37 #define PIO_SDOUTP_CLR  (0x24U)
  38 #define PIO_MUX_SET     (0x28U)
  39 #define PIO_MUX_CLR     (0x2CU)
  40 #define PIO_MUX_STATE   (0x30U)
  41
  42 static inline void gpio_lock(void)
  43 {
  44         local_irq_disable();
  45 }
  46
  47 static inline void gpio_unlock(void)
  48 {
  49         local_irq_enable();
  50 }
  51
  52 /* Inline functions */
  53 static inline int gpio_read_bit(u32 reg, int gpio)
  54 {
  55         u32 bit, val;
  56         int ret = -EFAULT;
  57
  58         if (gpio < 0)
  59                 goto out;
  60
  61         bit = GPIO_BIT(gpio);
  62         if (bit) {
  63                 val = __raw_readl(PIO_VA_BASE + reg);
  64                 ret = (val & bit) ? 1 : 0;
  65         }
  66 out:
  67         return ret;
  68 }
  69
  70 static inline int gpio_set_bit(u32 reg, int gpio)
  71 {
  72         u32 bit, val;
  73         int ret = -EFAULT;
  74
  75         if (gpio < 0)
  76                 goto out;
  77
  78         bit = GPIO_BIT(gpio);
  79         if (bit) {
  80                 val = __raw_readl(PIO_VA_BASE + reg);
  81                 val |= bit;
  82                 __raw_writel(val, PIO_VA_BASE + reg);
  83                 ret = 0;
  84         }
  85 out:
  86         return ret;
  87 }
  88
  89 /* Very simple access control, bitmap for allocated/free */
  90 static unsigned long access_map[4];
  91 #define INP_INDEX       0
  92 #define OUTP_INDEX      1
  93 #define GPIO_INDEX      2
  94 #define MUX_INDEX       3
  95
  96 /*GPIO to Input Mapping */
  97 static short gpio_to_inp_map[32] = {
  98         -1, -1, -1, -1, -1, -1, -1, -1,
  99         -1, -1, -1, -1, -1, -1, -1, -1,
 100         -1, -1, -1, -1, -1, -1, -1, -1,
 101         -1, 10, 11, 12, 13, 14, 24, -1
 102 };
 103
 104 /*GPIO to Mux Mapping */
 105 static short gpio_to_mux_map[32] = {
 106         -1, -1, -1, -1, -1, -1, -1, -1,
 107         -1, -1, -1, -1, -1, -1, -1, -1,
 108         -1, -1, -1, -1, -1, -1, -1, -1,
 109         -1, -1, -1, 0, 1, 4, 5, -1
 110 };
 111
 112 /*Output to Mux Mapping */
 113 static short outp_to_mux_map[32] = {
 114         -1, -1, -1, 6, -1, -1, -1, -1,
 115         -1, -1, -1, -1, -1, -1, -1, -1,
 116         -1, -1, -1, -1, -1, 2, -1, -1,
 117         -1, -1, -1, -1, -1, -1, -1, -1
 118 };
 119
 120 int pnx4008_gpio_register_pin(unsigned short pin)
 121 {
 122         unsigned long bit = GPIO_BIT(pin);
 123         int ret = -EBUSY;       /* Already in use */
 124
 125         gpio_lock();
 126
 127         if (GPIO_ISBID(pin)) {
 128                 if (access_map[GPIO_INDEX] & bit)
 129                         goto out;
 130                 access_map[GPIO_INDEX] |= bit;
 131
 132         } else if (GPIO_ISRAM(pin)) {
 133                 if (access_map[GPIO_INDEX] & bit)
 134                         goto out;
 135                 access_map[GPIO_INDEX] |= bit;
 136
 137         } else if (GPIO_ISMUX(pin)) {
 138                 if (access_map[MUX_INDEX] & bit)
 139                         goto out;
 140                 access_map[MUX_INDEX] |= bit;
 141
 142         } else if (GPIO_ISOUT(pin)) {
 143                 if (access_map[OUTP_INDEX] & bit)
 144                         goto out;
 145                 access_map[OUTP_INDEX] |= bit;
 146
 147         } else if (GPIO_ISIN(pin)) {
 148                 if (access_map[INP_INDEX] & bit)
 149                         goto out;
 150                 access_map[INP_INDEX] |= bit;
 151         } else
 152                 goto out;
 153         ret = 0;
 154
 155 out:
 156         gpio_unlock();
 157         return ret;
 158 }
 159
 160 EXPORT_SYMBOL(pnx4008_gpio_register_pin);
 161
 162 int pnx4008_gpio_unregister_pin(unsigned short pin)
 163 {
 164         unsigned long bit = GPIO_BIT(pin);
 165         int ret = -EFAULT;      /* Not registered */
 166
 167         gpio_lock();
 168
 169         if (GPIO_ISBID(pin)) {
 170                 if (~access_map[GPIO_INDEX] & bit)
 171                         goto out;
 172                 access_map[GPIO_INDEX] &= ~bit;
 173         } else if (GPIO_ISRAM(pin)) {
 174                 if (~access_map[GPIO_INDEX] & bit)
 175                         goto out;
 176                 access_map[GPIO_INDEX] &= ~bit;
 177         } else if (GPIO_ISMUX(pin)) {
 178                 if (~access_map[MUX_INDEX] & bit)
 179                         goto out;
 180                 access_map[MUX_INDEX] &= ~bit;
 181         } else if (GPIO_ISOUT(pin)) {
 182                 if (~access_map[OUTP_INDEX] & bit)
 183                         goto out;
 184                 access_map[OUTP_INDEX] &= ~bit;
 185         } else if (GPIO_ISIN(pin)) {
 186                 if (~access_map[INP_INDEX] & bit)
 187                         goto out;
 188                 access_map[INP_INDEX] &= ~bit;
 189         } else
 190                 goto out;
 191         ret = 0;
 192
 193 out:
 194         gpio_unlock();
 195         return ret;
 196 }
 197
 198 EXPORT_SYMBOL(pnx4008_gpio_unregister_pin);
 199
 200 unsigned long pnx4008_gpio_read_pin(unsigned short pin)
 201 {
 202         unsigned long ret = -EFAULT;
 203         int gpio = GPIO_BIT_MASK(pin);
 204         gpio_lock();
 205         if (GPIO_ISOUT(pin)) {
 206                 ret = gpio_read_bit(PIO_OUTP_STATE, gpio);
 207         } else if (GPIO_ISRAM(pin)) {
 208                 if (gpio_read_bit(PIO_DRV_STATE, gpio) == 0) {
 209                         ret = gpio_read_bit(PIO_SDINP_STATE, gpio);
 210                 }
 211         } else if (GPIO_ISBID(pin)) {
 212                 ret = gpio_read_bit(PIO_DRV_STATE, gpio);
 213                 if (ret > 0)
 214                         ret = gpio_read_bit(PIO_OUTP_STATE, gpio);
 215                 else if (ret == 0)
 216                         ret =
 217                             gpio_read_bit(PIO_INP_STATE, gpio_to_inp_map[gpio]);
 218         } else if (GPIO_ISIN(pin)) {
 219                 ret = gpio_read_bit(PIO_INP_STATE, gpio);
 220         }
 221         gpio_unlock();
 222         return ret;
 223 }
 224
 225 EXPORT_SYMBOL(pnx4008_gpio_read_pin);
 226
 227 /* Write Value to output */
 228 int pnx4008_gpio_write_pin(unsigned short pin, int output)
 229 {
 230         int gpio = GPIO_BIT_MASK(pin);
 231         int ret = -EFAULT;
 232
 233         gpio_lock();
 234         if (GPIO_ISOUT(pin)) {
 235                 printk( "writing '%x' to '%x'\n",
 236                                 gpio, output ? PIO_OUTP_SET : PIO_OUTP_CLR );
 237                 ret = gpio_set_bit(output ? PIO_OUTP_SET : PIO_OUTP_CLR, gpio);
 238         } else if (GPIO_ISRAM(pin)) {
 239                 if (gpio_read_bit(PIO_DRV_STATE, gpio) > 0)
 240                         ret = gpio_set_bit(output ? PIO_SDOUTP_SET :
 241                                            PIO_SDOUTP_CLR, gpio);
 242         } else if (GPIO_ISBID(pin)) {
 243                 if (gpio_read_bit(PIO_DRV_STATE, gpio) > 0)
 244                         ret = gpio_set_bit(output ? PIO_OUTP_SET :
 245                                            PIO_OUTP_CLR, gpio);
 246         }
 247         gpio_unlock();
 248         return ret;
 249 }
 250
 251 EXPORT_SYMBOL(pnx4008_gpio_write_pin);
 252
 253 /* Value = 1 : Set GPIO pin as output */
 254 /* Value = 0 : Set GPIO pin as input */
 255 int pnx4008_gpio_set_pin_direction(unsigned short pin, int output)
 256 {
 257         int gpio = GPIO_BIT_MASK(pin);
 258         int ret = -EFAULT;
 259
 260         gpio_lock();
 261         if (GPIO_ISBID(pin) || GPIO_ISRAM(pin)) {
 262                 ret = gpio_set_bit(output ? PIO_DRV_SET : PIO_DRV_CLR, gpio);
 263         }
 264         gpio_unlock();
 265         return ret;
 266 }
 267
 268 EXPORT_SYMBOL(pnx4008_gpio_set_pin_direction);
 269
 270 /* Read GPIO pin direction: 0= pin used as input, 1= pin used as output*/
 271 int pnx4008_gpio_read_pin_direction(unsigned short pin)
 272 {
 273         int gpio = GPIO_BIT_MASK(pin);
 274         int ret = -EFAULT;
 275
 276         gpio_lock();
 277         if (GPIO_ISBID(pin) || GPIO_ISRAM(pin)) {
 278                 ret = gpio_read_bit(PIO_DRV_STATE, gpio);
 279         }
 280         gpio_unlock();
 281         return ret;
 282 }
 283
 284 EXPORT_SYMBOL(pnx4008_gpio_read_pin_direction);
 285
 286 /* Value = 1 : Set pin to muxed function  */
 287 /* Value = 0 : Set pin as GPIO */
 288 int pnx4008_gpio_set_pin_mux(unsigned short pin, int output)
 289 {
 290         int gpio = GPIO_BIT_MASK(pin);
 291         int ret = -EFAULT;
 292
 293         gpio_lock();
 294         if (GPIO_ISBID(pin)) {
 295                 ret =
 296                     gpio_set_bit(output ? PIO_MUX_SET : PIO_MUX_CLR,
 297                                  gpio_to_mux_map[gpio]);
 298         } else if (GPIO_ISOUT(pin)) {
 299                 ret =
 300                     gpio_set_bit(output ? PIO_MUX_SET : PIO_MUX_CLR,
 301                                  outp_to_mux_map[gpio]);
 302         } else if (GPIO_ISMUX(pin)) {
 303                 ret = gpio_set_bit(output ? PIO_MUX_SET : PIO_MUX_CLR, gpio);
 304         }
 305         gpio_unlock();
 306         return ret;
 307 }
 308
 309 EXPORT_SYMBOL(pnx4008_gpio_set_pin_mux);
 310
 311 /* Read pin mux function: 0= pin used as GPIO, 1= pin used for muxed function*/
 312 int pnx4008_gpio_read_pin_mux(unsigned short pin)
 313 {
 314         int gpio = GPIO_BIT_MASK(pin);
 315         int ret = -EFAULT;
 316
 317         gpio_lock();
 318         if (GPIO_ISBID(pin)) {
 319                 ret = gpio_read_bit(PIO_MUX_STATE, gpio_to_mux_map[gpio]);
 320         } else if (GPIO_ISOUT(pin)) {
 321                 ret = gpio_read_bit(PIO_MUX_STATE, outp_to_mux_map[gpio]);
 322         } else if (GPIO_ISMUX(pin)) {
 323                 ret = gpio_read_bit(PIO_MUX_STATE, gpio);
 324         }
 325         gpio_unlock();
 326         return ret;
 327 }
 328
 329 EXPORT_SYMBOL(pnx4008_gpio_read_pin_mux);