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path: root/drivers/w1/slaves/w1_therm.c
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Diffstat (limited to 'drivers/w1/slaves/w1_therm.c')
-rw-r--r--drivers/w1/slaves/w1_therm.c139
1 files changed, 97 insertions, 42 deletions
diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c
index 1ed3d554e37..1f11a20a8ab 100644
--- a/drivers/w1/slaves/w1_therm.c
+++ b/drivers/w1/slaves/w1_therm.c
@@ -1,7 +1,7 @@
/*
* w1_therm.c
*
- * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
+ * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
*
*
* This program is free software; you can redistribute it and/or modify
@@ -27,6 +27,7 @@
#include <linux/sched.h>
#include <linux/device.h>
#include <linux/types.h>
+#include <linux/slab.h>
#include <linux/delay.h>
#include "../w1.h"
@@ -34,41 +35,59 @@
#include "../w1_family.h"
MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");
+MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
MODULE_DESCRIPTION("Driver for 1-wire Dallas network protocol, temperature family.");
+MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS18S20));
+MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS1822));
+MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS18B20));
+MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS1825));
+MODULE_ALIAS("w1-family-" __stringify(W1_THERM_DS28EA00));
/* Allow the strong pullup to be disabled, but default to enabled.
* If it was disabled a parasite powered device might not get the require
* current to do a temperature conversion. If it is enabled parasite powered
* devices have a better chance of getting the current required.
+ * In case the parasite power-detection is not working (seems to be the case
+ * for some DS18S20) the strong pullup can also be forced, regardless of the
+ * power state of the devices.
+ *
+ * Summary of options:
+ * - strong_pullup = 0 Disable strong pullup completely
+ * - strong_pullup = 1 Enable automatic strong pullup detection
+ * - strong_pullup = 2 Force strong pullup
*/
static int w1_strong_pullup = 1;
module_param_named(strong_pullup, w1_strong_pullup, int, 0);
-static u8 bad_roms[][9] = {
- {0xaa, 0x00, 0x4b, 0x46, 0xff, 0xff, 0x0c, 0x10, 0x87},
- {}
- };
-
-static ssize_t w1_therm_read(struct device *device,
- struct device_attribute *attr, char *buf);
-
-static struct device_attribute w1_therm_attr =
- __ATTR(w1_slave, S_IRUGO, w1_therm_read, NULL);
-
static int w1_therm_add_slave(struct w1_slave *sl)
{
- return device_create_file(&sl->dev, &w1_therm_attr);
+ sl->family_data = kzalloc(9, GFP_KERNEL);
+ if (!sl->family_data)
+ return -ENOMEM;
+ return 0;
}
static void w1_therm_remove_slave(struct w1_slave *sl)
{
- device_remove_file(&sl->dev, &w1_therm_attr);
+ kfree(sl->family_data);
+ sl->family_data = NULL;
}
+static ssize_t w1_slave_show(struct device *device,
+ struct device_attribute *attr, char *buf);
+
+static DEVICE_ATTR_RO(w1_slave);
+
+static struct attribute *w1_therm_attrs[] = {
+ &dev_attr_w1_slave.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(w1_therm);
+
static struct w1_family_ops w1_therm_fops = {
.add_slave = w1_therm_add_slave,
.remove_slave = w1_therm_remove_slave,
+ .groups = w1_therm_groups,
};
static struct w1_family w1_therm_family_DS18S20 = {
@@ -86,6 +105,16 @@ static struct w1_family w1_therm_family_DS1822 = {
.fops = &w1_therm_fops,
};
+static struct w1_family w1_therm_family_DS28EA00 = {
+ .fid = W1_THERM_DS28EA00,
+ .fops = &w1_therm_fops,
+};
+
+static struct w1_family w1_therm_family_DS1825 = {
+ .fid = W1_THERM_DS1825,
+ .fops = &w1_therm_fops,
+};
+
struct w1_therm_family_converter
{
u8 broken;
@@ -111,13 +140,20 @@ static struct w1_therm_family_converter w1_therm_families[] = {
.f = &w1_therm_family_DS18B20,
.convert = w1_DS18B20_convert_temp
},
+ {
+ .f = &w1_therm_family_DS28EA00,
+ .convert = w1_DS18B20_convert_temp
+ },
+ {
+ .f = &w1_therm_family_DS1825,
+ .convert = w1_DS18B20_convert_temp
+ }
};
static inline int w1_DS18B20_convert_temp(u8 rom[9])
{
- int t = ((s16)rom[1] << 8) | rom[0];
- t = t*1000/16;
- return t;
+ s16 t = le16_to_cpup((__le16 *)rom);
+ return t*1000/16;
}
static inline int w1_DS18S20_convert_temp(u8 rom[9])
@@ -151,44 +187,62 @@ static inline int w1_convert_temp(u8 rom[9], u8 fid)
return 0;
}
-static int w1_therm_check_rom(u8 rom[9])
-{
- int i;
-
- 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(struct device *device,
+static ssize_t w1_slave_show(struct device *device,
struct device_attribute *attr, char *buf)
{
struct w1_slave *sl = dev_to_w1_slave(device);
struct w1_master *dev = sl->master;
- u8 rom[9], crc, verdict;
+ u8 rom[9], crc, verdict, external_power;
int i, max_trying = 10;
ssize_t c = PAGE_SIZE;
- mutex_lock(&dev->mutex);
+ i = mutex_lock_interruptible(&dev->bus_mutex);
+ if (i != 0)
+ return i;
memset(rom, 0, sizeof(rom));
- verdict = 0;
- crc = 0;
-
while (max_trying--) {
+
+ verdict = 0;
+ crc = 0;
+
if (!w1_reset_select_slave(sl)) {
int count = 0;
unsigned int tm = 750;
+ unsigned long sleep_rem;
+
+ w1_write_8(dev, W1_READ_PSUPPLY);
+ external_power = w1_read_8(dev);
+
+ if (w1_reset_select_slave(sl))
+ continue;
/* 750ms strong pullup (or delay) after the convert */
- if (w1_strong_pullup)
+ if (w1_strong_pullup == 2 ||
+ (!external_power && w1_strong_pullup))
w1_next_pullup(dev, tm);
+
w1_write_8(dev, W1_CONVERT_TEMP);
- if (!w1_strong_pullup)
- msleep(tm);
+
+ if (external_power) {
+ mutex_unlock(&dev->bus_mutex);
+
+ sleep_rem = msleep_interruptible(tm);
+ if (sleep_rem != 0)
+ return -EINTR;
+
+ i = mutex_lock_interruptible(&dev->bus_mutex);
+ if (i != 0)
+ return i;
+ } else if (!w1_strong_pullup) {
+ sleep_rem = msleep_interruptible(tm);
+ if (sleep_rem != 0) {
+ mutex_unlock(&dev->bus_mutex);
+ return -EINTR;
+ }
+ }
if (!w1_reset_select_slave(sl)) {
@@ -206,7 +260,7 @@ static ssize_t w1_therm_read(struct device *device,
}
}
- if (!w1_therm_check_rom(rom))
+ if (verdict)
break;
}
@@ -215,16 +269,17 @@ static ssize_t w1_therm_read(struct device *device,
c -= snprintf(buf + PAGE_SIZE - c, c, ": crc=%02x %s\n",
crc, (verdict) ? "YES" : "NO");
if (verdict)
- memcpy(sl->rom, rom, sizeof(sl->rom));
+ memcpy(sl->family_data, rom, sizeof(rom));
else
- dev_warn(device, "18S20 doesn't respond to CONVERT_TEMP.\n");
+ dev_warn(device, "Read failed CRC check\n");
for (i = 0; i < 9; ++i)
- c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ", sl->rom[i]);
+ c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ",
+ ((u8 *)sl->family_data)[i]);
c -= snprintf(buf + PAGE_SIZE - c, c, "t=%d\n",
w1_convert_temp(rom, sl->family->fid));
- mutex_unlock(&dev->mutex);
+ mutex_unlock(&dev->bus_mutex);
return PAGE_SIZE - c;
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-12 14:07:11 +0000