vserver 1.9.5.x5

[linux-2.6.git] / drivers / w1 / w1_therm.c

diff --git a/drivers/w1/w1_therm.c b/drivers/w1/w1_therm.c
index 3eed829..8ca23df 100644 (file)
--- a/drivers/w1/w1_therm.c
+++ b/drivers/w1/w1_therm.c
@@ -36,6 +36,11 @@ MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
 MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol, temperature family.");
 
+static u8 bad_roms[][9] = {
+                               {0xaa, 0x00, 0x4b, 0x46, 0xff, 0xff, 0x0c, 0x10, 0x87}, 
+                               {}
+                       };
+
 static ssize_t w1_therm_read_name(struct device *, char *);
 static ssize_t w1_therm_read_temp(struct device *, char *);
 static ssize_t w1_therm_read_bin(struct kobject *, char *, loff_t, size_t);
@@ -54,19 +59,39 @@ static ssize_t w1_therm_read_name(struct device *dev, char *buf)
        return sprintf(buf, "%s\n", sl->name);
 }
 
+static inline int w1_convert_temp(u8 rom[9])
+{
+       int t, h;
+       
+       if (rom[1] == 0)
+               t = ((s32)rom[0] >> 1)*1000;
+       else
+               t = 1000*(-1*(s32)(0x100-rom[0]) >> 1);
+       
+       t -= 250;
+       h = 1000*((s32)rom[7] - (s32)rom[6]);
+       h /= (s32)rom[7];
+       t += h;
+
+       return t;
+}
+
 static ssize_t w1_therm_read_temp(struct device *dev, char *buf)
 {
        struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
-       s16 temp;
 
-       /* 
-        * Must be more precise.
-        */
-       temp = 0;
-       temp <<= sl->rom[1] / 2;
-       temp |= sl->rom[0] / 2;
+       return sprintf(buf, "%d\n", w1_convert_temp(sl->rom));
+}
+
+static int w1_therm_check_rom(u8 rom[9])
+{
+       int i;
 
-       return sprintf(buf, "%d\n", temp * 1000);
+       for (i=0; i<sizeof(bad_roms)/9; ++i)
+               if (!memcmp(bad_roms[i], rom, 9))
+                       return 1;
+
+       return 0;
 }
 
 static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, size_t count)
@@ -75,9 +100,7 @@ static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, si
                                                struct w1_slave, dev);
        struct w1_master *dev = sl->master;
        u8 rom[9], crc, verdict;
-       size_t icount;
-       int i;
-       u16 temp;
+       int i, max_trying = 10;
 
        atomic_inc(&sl->refcnt);
        if (down_interruptible(&sl->master->mutex)) {
@@ -89,10 +112,10 @@ static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, si
                count = 0;
                goto out;
        }
-       if (off + count > W1_SLAVE_DATA_SIZE)
-               count = W1_SLAVE_DATA_SIZE - off;
-
-       icount = count;
+       if (off + count > W1_SLAVE_DATA_SIZE) {
+               count = 0;
+               goto out;
+       }
 
        memset(buf, 0, count);
        memset(rom, 0, sizeof(rom));
@@ -100,56 +123,61 @@ static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, si
        count = 0;
        verdict = 0;
        crc = 0;
-       if (!w1_reset_bus(dev)) {
-               u64 id = *(u64 *) & sl->reg_num;
-               int count = 0;
 
-               w1_write_8(dev, W1_MATCH_ROM);
-               for (i = 0; i < 8; ++i)
-                       w1_write_8(dev, (id >> i * 8) & 0xff);
+       while (max_trying--) {
+               if (!w1_reset_bus (dev)) {
+                       int count = 0;
+                       u8 match[9] = {W1_MATCH_ROM, };
+                       unsigned long tm;
 
-               w1_write_8(dev, W1_CONVERT_TEMP);
+                       memcpy(&match[1], (u64 *) & sl->reg_num, 8);
+                       
+                       w1_write_block(dev, match, 9);
 
-               while (dev->bus_master->read_bit(dev->bus_master->data) == 0
-                      && count < 10) {
-                       w1_delay(1);
-                       count++;
-               }
+                       w1_write_8(dev, W1_CONVERT_TEMP);
 
-               if (count < 10) {
-                       if (!w1_reset_bus(dev)) {
-                               w1_write_8(dev, W1_MATCH_ROM);
-                               for (i = 0; i < 8; ++i)
-                                       w1_write_8(dev,
-                                                  (id >> i * 8) & 0xff);
+                       tm = jiffies + msecs_to_jiffies(750);
+                       while(time_before(jiffies, tm)) {
+                               set_current_state(TASK_INTERRUPTIBLE);
+                               schedule_timeout(tm-jiffies);
 
+                               if (signal_pending(current))
+                                       flush_signals(current);
+                       }
+
+                       if (!w1_reset_bus (dev)) {
+                               w1_write_block(dev, match, 9);
+                               
                                w1_write_8(dev, W1_READ_SCRATCHPAD);
-                               for (i = 0; i < 9; ++i)
-                                       rom[i] = w1_read_8(dev);
+                               if ((count = w1_read_block(dev, rom, 9)) != 9) {
+                                       dev_warn(&dev->dev, "w1_read_block() returned %d instead of 9.\n", count);
+                               }
 
                                crc = w1_calc_crc8(rom, 8);
 
                                if (rom[8] == crc && rom[0])
                                        verdict = 1;
+
                        }
                }
-               else
-                       dev_warn(&dev->dev,
-                                 "18S20 doesn't respond to CONVERT_TEMP.\n");
+
+               if (!w1_therm_check_rom(rom))
+                       break;
        }
 
        for (i = 0; i < 9; ++i)
-               count += snprintf(buf + count, icount - count, "%02x ", rom[i]);
-       count += snprintf(buf + count, icount - count, ": crc=%02x %s\n",
+               count += sprintf(buf + count, "%02x ", rom[i]);
+       count += sprintf(buf + count, ": crc=%02x %s\n",
                           crc, (verdict) ? "YES" : "NO");
        if (verdict)
                memcpy(sl->rom, rom, sizeof(sl->rom));
+       else
+               dev_warn(&dev->dev, "18S20 doesn't respond to CONVERT_TEMP.\n");
+
        for (i = 0; i < 9; ++i)
-               count += snprintf(buf + count, icount - count, "%02x ", sl->rom[i]);
-       temp = 0;
-       temp <<= sl->rom[1] / 2;
-       temp |= sl->rom[0] / 2;
-       count += snprintf(buf + count, icount - count, "t=%u\n", temp);
+               count += sprintf(buf + count, "%02x ", sl->rom[i]);
+       
+       count += sprintf(buf + count, "t=%d\n", w1_convert_temp(rom));
 out:
        up(&dev->mutex);
 out_dec: