diff options
Diffstat (limited to 'drivers/w1/slaves/w1_therm.c')
| -rw-r--r-- | drivers/w1/slaves/w1_therm.c | 76 |
1 files changed, 44 insertions, 32 deletions
diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c index 92d08e7fcba..1f11a20a8ab 100644 --- a/drivers/w1/slaves/w1_therm.c +++ b/drivers/w1/slaves/w1_therm.c @@ -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" @@ -36,39 +37,57 @@ MODULE_LICENSE("GPL"); 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 = { @@ -168,18 +187,8 @@ 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); @@ -194,10 +203,11 @@ static ssize_t w1_therm_read(struct device *device, 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; @@ -210,7 +220,8 @@ static ssize_t w1_therm_read(struct device *device, continue; /* 750ms strong pullup (or delay) after the convert */ - if (!external_power && 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); @@ -249,7 +260,7 @@ static ssize_t w1_therm_read(struct device *device, } } - if (!w1_therm_check_rom(rom)) + if (verdict) break; } @@ -258,12 +269,13 @@ 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)); |