diff options
| author | Evgeniy Polyakov <johnpol@2ka.mipt.ru> | 2005-08-11 17:27:49 +0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2005-09-09 01:41:26 +0400 |
| commit | ea7d8f65c865ebfa1d7cd67c360a87333ff013c1 (patch) | |
| tree | 1e687c32d53a92c10a61fb23ab14763459ff5779 /drivers/w1 | |
| parent | db2d0008de519c5db6baec45f7831e08790301cf (diff) | |
| download | linux-ea7d8f65c865ebfa1d7cd67c360a87333ff013c1.tar.xz | |
[PATCH] w1: Added w1_reset_select_slave() - Resets the bus and then selects the slave by
sending either a skip rom or a rom match.
Patch from Ben Gardner <bgardner@wabtec.com>
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/w1')
| -rw-r--r-- | drivers/w1/w1_io.c | 24 | ||||
| -rw-r--r-- | drivers/w1/w1_io.h | 1 | ||||
| -rw-r--r-- | drivers/w1/w1_therm.c | 11 |
3 files changed, 27 insertions, 9 deletions
diff --git a/drivers/w1/w1_io.c b/drivers/w1/w1_io.c index 00f032220173..e2a043354ddf 100644 --- a/drivers/w1/w1_io.c +++ b/drivers/w1/w1_io.c @@ -277,6 +277,29 @@ void w1_search_devices(struct w1_master *dev, w1_slave_found_callback cb) w1_search(dev, cb); } +/** + * Resets the bus and then selects the slave by sending either a skip rom + * or a rom match. + * The w1 master lock must be held. + * + * @param sl the slave to select + * @return 0=success, anything else=error + */ +int w1_reset_select_slave(struct w1_slave *sl) +{ + if (w1_reset_bus(sl->master)) + return -1; + + if (sl->master->slave_count == 1) + w1_write_8(sl->master, W1_SKIP_ROM); + else { + u8 match[9] = {W1_MATCH_ROM, }; + memcpy(&match[1], (u8 *)&sl->reg_num, 8); + w1_write_block(sl->master, match, 9); + } + return 0; +} + EXPORT_SYMBOL(w1_touch_bit); EXPORT_SYMBOL(w1_write_8); EXPORT_SYMBOL(w1_read_8); @@ -286,3 +309,4 @@ EXPORT_SYMBOL(w1_delay); EXPORT_SYMBOL(w1_read_block); EXPORT_SYMBOL(w1_write_block); EXPORT_SYMBOL(w1_search_devices); +EXPORT_SYMBOL(w1_reset_select_slave); diff --git a/drivers/w1/w1_io.h b/drivers/w1/w1_io.h index af5829778aaa..232860184a29 100644 --- a/drivers/w1/w1_io.h +++ b/drivers/w1/w1_io.h @@ -34,5 +34,6 @@ u8 w1_calc_crc8(u8 *, int); void w1_write_block(struct w1_master *, const u8 *, int); u8 w1_read_block(struct w1_master *, u8 *, int); void w1_search_devices(struct w1_master *dev, w1_slave_found_callback cb); +int w1_reset_select_slave(struct w1_slave *sl); #endif /* __W1_IO_H */ diff --git a/drivers/w1/w1_therm.c b/drivers/w1/w1_therm.c index 2259f3d851ff..2ed0e0f48268 100644 --- a/drivers/w1/w1_therm.c +++ b/drivers/w1/w1_therm.c @@ -176,15 +176,10 @@ static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, si crc = 0; while (max_trying--) { - if (!w1_reset_bus (dev)) { + if (!w1_reset_select_slave(sl)) { int count = 0; - u8 match[9] = {W1_MATCH_ROM, }; unsigned int tm = 750; - memcpy(&match[1], (u64 *) & sl->reg_num, 8); - - w1_write_block(dev, match, 9); - w1_write_8(dev, W1_CONVERT_TEMP); while (tm) { @@ -193,8 +188,7 @@ static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, si flush_signals(current); } - if (!w1_reset_bus (dev)) { - w1_write_block(dev, match, 9); + if (!w1_reset_select_slave(sl)) { w1_write_8(dev, W1_READ_SCRATCHPAD); if ((count = w1_read_block(dev, rom, 9)) != 9) { @@ -205,7 +199,6 @@ static ssize_t w1_therm_read_bin(struct kobject *kobj, char *buf, loff_t off, si if (rom[8] == crc && rom[0]) verdict = 1; - } } |