diff options
Diffstat (limited to 'drivers/w1')
| -rw-r--r-- | drivers/w1/w1_int.c | 8 | ||||
| -rw-r--r-- | drivers/w1/w1_io.c | 70 | ||||
| -rw-r--r-- | drivers/w1/w1_io.h | 4 |
3 files changed, 70 insertions, 12 deletions
diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c index ce24e3b..280f140 100644 --- a/drivers/w1/w1_int.c +++ b/drivers/w1/w1_int.c @@ -121,6 +121,14 @@ int w1_add_master_device(struct w1_bus_master *master) int retval = 0; struct w1_netlink_msg msg; + /* validate minimum functionality */ + if (!(master->touch_bit && master->reset_bus) && + !(master->write_bit && master->read_bit)) + { + printk(KERN_ERR "w1_add_master_device: invalid function set\n"); + return(-EINVAL); + } + dev = w1_alloc_dev(w1_ids++, w1_max_slave_count, w1_max_slave_ttl, &w1_driver, &w1_device); if (!dev) return -ENOMEM; diff --git a/drivers/w1/w1_io.c b/drivers/w1/w1_io.c index 298ee8b..2173336 100644 --- a/drivers/w1/w1_io.c +++ b/drivers/w1/w1_io.c @@ -55,15 +55,29 @@ void w1_delay(unsigned long tm) udelay(tm * w1_delay_parm); } +static void w1_write_bit(struct w1_master *dev, int bit); +static u8 w1_read_bit(struct w1_master *dev); + +/** + * Generates a write-0 or write-1 cycle and samples the level. + */ u8 w1_touch_bit(struct w1_master *dev, int bit) { if (dev->bus_master->touch_bit) return dev->bus_master->touch_bit(dev->bus_master->data, bit); - else + else if (bit) return w1_read_bit(dev); + else { + w1_write_bit(dev, 0); + return(0); + } } -void w1_write_bit(struct w1_master *dev, int bit) +/** + * Generates a write-0 or write-1 cycle. + * Only call if dev->bus_master->touch_bit is NULL + */ +static void w1_write_bit(struct w1_master *dev, int bit) { if (bit) { dev->bus_master->write_bit(dev->bus_master->data, 0); @@ -78,6 +92,12 @@ void w1_write_bit(struct w1_master *dev, int bit) } } +/** + * Writes 8 bits. + * + * @param dev the master device + * @param byte the byte to write + */ void w1_write_8(struct w1_master *dev, u8 byte) { int i; @@ -86,10 +106,15 @@ void w1_write_8(struct w1_master *dev, u8 byte) dev->bus_master->write_byte(dev->bus_master->data, byte); else for (i = 0; i < 8; ++i) - w1_write_bit(dev, (byte >> i) & 0x1); + w1_touch_bit(dev, (byte >> i) & 0x1); } -u8 w1_read_bit(struct w1_master *dev) + +/** + * Generates a write-1 cycle and samples the level. + * Only call if dev->bus_master->touch_bit is NULL + */ +static u8 w1_read_bit(struct w1_master *dev) { int result; @@ -104,6 +129,12 @@ u8 w1_read_bit(struct w1_master *dev) return result & 0x1; } +/** + * Reads 8 bits. + * + * @param dev the master device + * @return the byte read + */ u8 w1_read_8(struct w1_master * dev) { int i; @@ -113,12 +144,20 @@ u8 w1_read_8(struct w1_master * dev) res = dev->bus_master->read_byte(dev->bus_master->data); else for (i = 0; i < 8; ++i) - res |= (w1_read_bit(dev) << i); + res |= (w1_touch_bit(dev,1) << i); return res; } -void w1_write_block(struct w1_master *dev, u8 *buf, int len) +/** + * Writes a series of bytes. + * + * @param dev the master device + * @param buf pointer to the data to write + * @param len the number of bytes to write + * @return the byte read + */ +void w1_write_block(struct w1_master *dev, const u8 *buf, int len) { int i; @@ -129,6 +168,14 @@ void w1_write_block(struct w1_master *dev, u8 *buf, int len) w1_write_8(dev, buf[i]); } +/** + * Reads a series of bytes. + * + * @param dev the master device + * @param buf pointer to the buffer to fill + * @param len the number of bytes to read + * @return the number of bytes read + */ u8 w1_read_block(struct w1_master *dev, u8 *buf, int len) { int i; @@ -145,9 +192,15 @@ u8 w1_read_block(struct w1_master *dev, u8 *buf, int len) return ret; } +/** + * Issues a reset bus sequence. + * + * @param dev The bus master pointer + * @return 0=Device present, 1=No device present or error + */ int w1_reset_bus(struct w1_master *dev) { - int result = 0; + int result; if (dev->bus_master->reset_bus) result = dev->bus_master->reset_bus(dev->bus_master->data) & 0x1; @@ -183,9 +236,8 @@ void w1_search_devices(struct w1_master *dev, w1_slave_found_callback cb) w1_search(dev); } -EXPORT_SYMBOL(w1_write_bit); +EXPORT_SYMBOL(w1_touch_bit); EXPORT_SYMBOL(w1_write_8); -EXPORT_SYMBOL(w1_read_bit); EXPORT_SYMBOL(w1_read_8); EXPORT_SYMBOL(w1_reset_bus); EXPORT_SYMBOL(w1_calc_crc8); diff --git a/drivers/w1/w1_io.h b/drivers/w1/w1_io.h index 327c22b..d6daa31 100644 --- a/drivers/w1/w1_io.h +++ b/drivers/w1/w1_io.h @@ -26,13 +26,11 @@ void w1_delay(unsigned long); u8 w1_touch_bit(struct w1_master *, int); -void w1_write_bit(struct w1_master *, int); void w1_write_8(struct w1_master *, u8); -u8 w1_read_bit(struct w1_master *); u8 w1_read_8(struct w1_master *); int w1_reset_bus(struct w1_master *); u8 w1_calc_crc8(u8 *, int); -void w1_write_block(struct w1_master *, 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); |
