target/linux/pxa/patches-2.6.21/011-proc-gpio.patch

   1 --- a/arch/arm/Kconfig
   2 +++ b/arch/arm/Kconfig
   3 @@ -505,6 +505,8 @@
   4         depends on PCI && ARCH_SHARK
   5         default y
   6
   7 +source "drivers/gpio/Kconfig"
   8 +
   9  source "drivers/pci/Kconfig"
  10
  11  source "drivers/pcmcia/Kconfig"
  12 --- a/drivers/Makefile
  13 +++ b/drivers/Makefile
  14 @@ -81,3 +81,4 @@
  15  obj-$(CONFIG_DMA_ENGINE)       += dma/
  16  obj-$(CONFIG_HID)              += hid/
  17  obj-$(CONFIG_PPC_PS3)          += ps3/
  18 +obj-$(CONFIG_PROC_GPIO)                += gpio/
  19 --- /dev/null
  20 +++ b/drivers/gpio/Kconfig
  21 @@ -0,0 +1,13 @@
  22 +config PROC_GPIO
  23 +       tristate "GPIO /proc interface"
  24 +       depends on PXA25x || PXA27x
  25 +       help
  26 +         This enables an interface under /proc/gpio which allows reading or setting
  27 +         of any GPIO, and also changing the GPIO alt function mode of any line.
  28 +
  29 +config PROC_GPIO_DEBUG
  30 +       boolean "Enable /proc/gpio debug logging"
  31 +       depends on PROC_GPIO
  32 +       help
  33 +         This enables printk logging of activity done through /proc/gpio
  34 +
  35 --- /dev/null
  36 +++ b/drivers/gpio/Makefile
  37 @@ -0,0 +1,2 @@
  38 +# Expose GPIOs under /proc
  39 +obj-$(CONFIG_PROC_GPIO)                += proc_gpio.o
  40 --- /dev/null
  41 +++ b/drivers/gpio/proc_gpio.c
  42 @@ -0,0 +1,276 @@
  43 +/*
  44 + *
  45 + *  PXA25x GPIOs exposed under /proc for reading and writing
  46 + *  They will show up under /proc/gpio/NN
  47 + *
  48 + *  Based on patch 1773/1 in the arm kernel patch repository at arm.linux.co.uk
  49 + *
  50 + */
  51 +
  52 +#include <linux/module.h>
  53 +#include <linux/init.h>
  54 +#include <linux/proc_fs.h>
  55 +#include <linux/string.h>
  56 +#include <linux/ctype.h>
  57 +
  58 +#include <asm/hardware.h>
  59 +#include <asm/arch/pxa-regs.h>
  60 +#include <asm/uaccess.h>
  61 +
  62 +static struct proc_dir_entry *proc_gpio_parent;
  63 +static struct proc_dir_entry *proc_gpios[PXA_LAST_GPIO + 1];
  64 +
  65 +typedef struct
  66 +{
  67 +       int     gpio;
  68 +       char    name[32];
  69 +} gpio_summary_type;
  70 +
  71 +static gpio_summary_type gpio_summaries[PXA_LAST_GPIO + 1];
  72 +
  73 +static int proc_gpio_write(struct file *file, const char __user *buf,
  74 +                           unsigned long count, void *data)
  75 +{
  76 +       char *cur, lbuf[count + 1];
  77 +       gpio_summary_type *summary = data;
  78 +       u32 altfn, direction, setclear, gafr;
  79 +
  80 +       if (!capable(CAP_SYS_ADMIN))
  81 +               return -EACCES;
  82 +
  83 +       memset(lbuf, 0, count + 1);
  84 +
  85 +       if (copy_from_user(lbuf, buf, count))
  86 +               return -EFAULT;
  87 +
  88 +       cur = lbuf;
  89 +
  90 +       // Initialize to current state
  91 +       altfn = ((GAFR(summary->gpio) >> ((summary->gpio & 0x0f) << 0x01)) & 0x03);
  92 +       direction = GPDR(summary->gpio) & GPIO_bit(summary->gpio);
  93 +       setclear = GPLR(summary->gpio) & GPIO_bit(summary->gpio);
  94 +       while(1)
  95 +       {
  96 +               // We accept options: {GPIO|AF1|AF2|AF3}, {set|clear}, {in|out}
  97 +               // Anything else is an error
  98 +               while(cur[0] && (isspace(cur[0]) || ispunct(cur[0]))) cur = &(cur[1]);
  99 +
 100 +               if('\0' == cur[0]) break;
 101 +
 102 +               // Ok, so now we're pointing at the start of something
 103 +               switch(cur[0])
 104 +               {
 105 +                       case 'G':
 106 +                               // Check that next is "PIO" -- '\0' will cause safe short-circuit if end of buf
 107 +                               if(!(cur[1] == 'P' && cur[2] == 'I' && cur[3] == 'O')) goto parse_error;
 108 +                               // Ok, so set this GPIO to GPIO (non-ALT) function
 109 +                               altfn = 0;
 110 +                               cur = &(cur[4]);
 111 +                               break;
 112 +                       case 'A':
 113 +                               if(!(cur[1] == 'F' && cur[2] >= '1' && cur[2] <= '3')) goto parse_error;
 114 +                               altfn = cur[2] - '0';
 115 +                               cur = &(cur[3]);
 116 +                               break;
 117 +                       case 's':
 118 +                               if(!(cur[1] == 'e' && cur[2] == 't')) goto parse_error;
 119 +                               setclear = 1;
 120 +                               cur = &(cur[3]);
 121 +                               break;
 122 +                       case 'c':
 123 +                               if(!(cur[1] == 'l' && cur[2] == 'e' && cur[3] == 'a' && cur[4] == 'r')) goto parse_error;
 124 +                               setclear = 0;
 125 +                               cur = &(cur[5]);
 126 +                               break;
 127 +                       case 'i':
 128 +                               if(!(cur[1] == 'n')) goto parse_error;
 129 +                               direction = 0;
 130 +                               cur = &(cur[2]);
 131 +                               break;
 132 +                       case 'o':
 133 +                               if(!(cur[1] == 'u' && cur[2] == 't')) goto parse_error;
 134 +                               direction = 1;
 135 +                               cur = &(cur[3]);
 136 +                               break;
 137 +                       default: goto parse_error;
 138 +               }
 139 +       }
 140 +       // Ok, now set gpio mode and value
 141 +       if(direction)
 142 +               GPDR(summary->gpio) |= GPIO_bit(summary->gpio);
 143 +       else
 144 +               GPDR(summary->gpio) &= ~GPIO_bit(summary->gpio);
 145 +
 146 +       gafr = GAFR(summary->gpio) & ~(0x3 << (((summary->gpio) & 0xf)*2));
 147 +       GAFR(summary->gpio) = gafr |  (altfn  << (((summary->gpio) & 0xf)*2));
 148 +
 149 +       if(direction && !altfn)
 150 +       {
 151 +               if(setclear) GPSR(summary->gpio) = GPIO_bit(summary->gpio);
 152 +               else GPCR(summary->gpio) = GPIO_bit(summary->gpio);
 153 +       }
 154 +
 155 +#ifdef CONFIG_PROC_GPIO_DEBUG
 156 +       printk(KERN_INFO "Set (%s,%s,%s) via /proc/gpio/%s\n",altfn ? (altfn == 1 ? "AF1" : (altfn == 2 ? "AF2" : "AF3")) : "GPIO",
 157 +                               direction ? "out" : "in",
 158 +                               setclear ? "set" : "clear",
 159 +                               summary->name);
 160 +#endif
 161 +
 162 +       return count;
 163 +
 164 +parse_error:
 165 +       printk(KERN_CRIT "Parse error: Expect \"[GPIO|AF1|AF2|AF3]|[set|clear]|[in|out] ...\"\n");
 166 +       return -EINVAL;
 167 +}
 168 +
 169 +static int proc_gpio_read(char *page, char **start, off_t off,
 170 +                       int count, int *eof, void *data)
 171 +{
 172 +       char *p = page;
 173 +       gpio_summary_type *summary = data;
 174 +       int len, i, af;
 175 +       i = summary->gpio;
 176 +
 177 +       p += sprintf(p, "%d\t%s\t%s\t%s\n", i,
 178 +                       (af = ((GAFR(i) >> ((i & 0x0f) << 0x01)) & 0x03)) ? (af == 1 ? "AF1" : (af == 2 ? "AF2" : "AF3")) : "GPIO",
 179 +                       (GPDR(i) & GPIO_bit(i)) ? "out" : "in",
 180 +                       (GPLR(i) & GPIO_bit(i)) ? "set" : "clear");
 181 +
 182 +       len = (p - page) - off;
 183 +
 184 +       if(len < 0)
 185 +       {
 186 +               len = 0;
 187 +       }
 188 +
 189 +       *eof = (len <= count) ? 1 : 0;
 190 +       *start = page + off;
 191 +
 192 +       return len;
 193 +}
 194 +
 195 +
 196 +#ifdef CONFIG_PXA25x
 197 +static const char const *GAFR_DESC[] = { "GAFR0_L", "GAFR0_U", "GAFR1_L", "GAFR1_U", "GAFR2_L", "GAFR2_U" };
 198 +#elif defined(CONFIG_PXA27x)
 199 +static const char const *GAFR_DESC[] = { "GAFR0_L", "GAFR0_U", "GAFR1_L", "GAFR1_U", "GAFR2_L", "GAFR2_U", "GAFR3_L", "GAFR3_U" };
 200 +#endif
 201 +
 202 +static int proc_gafr_read(char *page, char **start, off_t off,
 203 +                       int count, int *eof, void *data)
 204 +{
 205 +       char *p = page;
 206 +       int i, len;
 207 +
 208 +       for(i=0; i<ARRAY_SIZE(GAFR_DESC); i++)
 209 +       {
 210 +               p += sprintf(p, "%s: %08x\n", GAFR_DESC[i], GAFR(i*16));
 211 +       }
 212 +
 213 +       len = (p - page) - off;
 214 +
 215 +       if(len < 0)
 216 +       {
 217 +               len = 0;
 218 +       }
 219 +
 220 +       *eof = (len <= count) ? 1 : 0;
 221 +       *start = page + off;
 222 +
 223 +       return len;
 224 +}
 225 +
 226 +static int proc_gpdr_read(char *page, char **start, off_t off,
 227 +                       int count, int *eof, void *data)
 228 +{
 229 +       char *p = page;
 230 +       int i, len;
 231 +
 232 +       for(i=0; i<=2; i++)
 233 +       {
 234 +               p += sprintf(p, "GPDR%d: %08x\n", i, GPDR(i * 32));
 235 +       }
 236 +
 237 +       len = (p - page) - off;
 238 +
 239 +       if(len < 0)
 240 +       {
 241 +               len = 0;
 242 +       }
 243 +
 244 +       *eof = (len <= count) ? 1 : 0;
 245 +       *start = page + off;
 246 +
 247 +       return len;
 248 +}
 249 +
 250 +static int proc_gplr_read(char *page, char **start, off_t off,
 251 +                       int count, int *eof, void *data)
 252 +{
 253 +       char *p = page;
 254 +       int i, len;
 255 +
 256 +       for(i=0; i<=2; i++)
 257 +       {
 258 +               p += sprintf(p, "GPLR%d: %08x\n", i, GPLR(i * 32));
 259 +       }
 260 +
 261 +       len = (p - page) - off;
 262 +
 263 +       if(len < 0)
 264 +       {
 265 +               len = 0;
 266 +       }
 267 +
 268 +       *eof = (len <= count) ? 1 : 0;
 269 +       *start = page + off;
 270 +
 271 +       return len;
 272 +}
 273 +
 274 +static int __init gpio_init(void)
 275 +{
 276 +       int i;
 277 +
 278 +       proc_gpio_parent = create_proc_entry("gpio", S_IFDIR | S_IRUGO | S_IXUGO, NULL);
 279 +       if(!proc_gpio_parent) return 0;
 280 +
 281 +       for(i=0; i < (PXA_LAST_GPIO+1); i++)
 282 +       {
 283 +               gpio_summaries[i].gpio = i;
 284 +               sprintf(gpio_summaries[i].name, "GPIO%d", i);
 285 +               proc_gpios[i] = create_proc_entry(gpio_summaries[i].name, 0644, proc_gpio_parent);
 286 +               if(proc_gpios[i])
 287 +               {
 288 +                       proc_gpios[i]->data = &gpio_summaries[i];
 289 +                       proc_gpios[i]->read_proc = proc_gpio_read;
 290 +                       proc_gpios[i]->write_proc = proc_gpio_write;
 291 +               }
 292 +       }
 293 +
 294 +       create_proc_read_entry("GAFR", 0444, proc_gpio_parent, proc_gafr_read, NULL);
 295 +       create_proc_read_entry("GPDR", 0444, proc_gpio_parent, proc_gpdr_read, NULL);
 296 +       create_proc_read_entry("GPLR", 0444, proc_gpio_parent, proc_gplr_read, NULL);
 297 +
 298 +       return 0;
 299 +}
 300 +
 301 +static void gpio_exit(void)
 302 +{
 303 +       int i;
 304 +
 305 +       remove_proc_entry("GAFR", proc_gpio_parent);
 306 +       remove_proc_entry("GPDR", proc_gpio_parent);
 307 +       remove_proc_entry("GPLR", proc_gpio_parent);
 308 +
 309 +       for(i=0; i < (PXA_LAST_GPIO+1); i++)
 310 +       {
 311 +               if(proc_gpios[i]) remove_proc_entry(gpio_summaries[i].name, proc_gpio_parent);
 312 +       }
 313 +       if(proc_gpio_parent) remove_proc_entry("gpio", NULL);
 314 +}
 315 +
 316 +module_init(gpio_init);
 317 +module_exit(gpio_exit);
 318 +MODULE_LICENSE("GPL");