Commit ea7d8f65 authored by Evgeniy Polyakov's avatar Evgeniy Polyakov Committed by Greg Kroah-Hartman
Browse files

[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: default avatarEvgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent db2d0008

drivers/w1/w1_io.c

+24 −0
Original line number Diff line number Diff line
@@ -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);

drivers/w1/w1_io.h

+1 −0
Original line number Diff line number Diff line
@@ -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 */

drivers/w1/w1_therm.c

+2 −9
Original line number Diff line number Diff line
@@ -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;



			}

		}