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