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Diffstat (limited to 'drivers/w1/w1.c')
-rw-r--r--drivers/w1/w1.c30
1 files changed, 26 insertions, 4 deletions
diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
index 53846c7f24ff..9eb816b2ea5e 100644
--- a/drivers/w1/w1.c
+++ b/drivers/w1/w1.c
@@ -50,8 +50,21 @@ int w1_max_slave_count = 64;
int w1_max_slave_ttl = 10;
module_param_named(timeout, w1_timeout, int, 0);
+MODULE_PARM_DESC(timeout, "time in seconds between automatic slave searches");
+/* A search stops when w1_max_slave_count devices have been found in that
+ * search. The next search will start over and detect the same set of devices
+ * on a static 1-wire bus. Memory is not allocated based on this number, just
+ * on the number of devices known to the kernel. Having a high number does not
+ * consume additional resources. As a special case, if there is only one
+ * device on the network and w1_max_slave_count is set to 1, the device id can
+ * be read directly skipping the normal slower search process.
+ */
module_param_named(max_slave_count, w1_max_slave_count, int, 0);
+MODULE_PARM_DESC(max_slave_count,
+ "maximum number of slaves detected in a search");
module_param_named(slave_ttl, w1_max_slave_ttl, int, 0);
+MODULE_PARM_DESC(slave_ttl,
+ "Number of searches not seeing a slave before it will be removed");
DEFINE_MUTEX(w1_mlock);
LIST_HEAD(w1_masters);
@@ -920,7 +933,12 @@ void w1_slave_found(struct w1_master *dev, u64 rn)
}
/**
- * Performs a ROM Search & registers any devices found.
+ * w1_search() - Performs a ROM Search & registers any devices found.
+ * @dev: The master device to search
+ * @search_type: W1_SEARCH to search all devices, or W1_ALARM_SEARCH
+ * to return only devices in the alarmed state
+ * @cb: Function to call when a device is found
+ *
* The 1-wire search is a simple binary tree search.
* For each bit of the address, we read two bits and write one bit.
* The bit written will put to sleep all devies that don't match that bit.
@@ -930,8 +948,6 @@ void w1_slave_found(struct w1_master *dev, u64 rn)
*
* See "Application note 187 1-wire search algorithm" at www.maxim-ic.com
*
- * @dev The master device to search
- * @cb Function to call when a device is found
*/
void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb)
{
@@ -990,7 +1006,7 @@ void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb
else
search_bit = ((last_rn >> i) & 0x1);
- /** Read two bits and write one bit */
+ /* Read two bits and write one bit */
triplet_ret = w1_triplet(dev, search_bit);
/* quit if no device responded */
@@ -1074,6 +1090,12 @@ static void w1_search_process(struct w1_master *dev, u8 search_type)
w1_search_process_cb(dev, search_type, w1_slave_found);
}
+/**
+ * w1_process_callbacks() - execute each dev->async_list callback entry
+ * @dev: w1_master device
+ *
+ * Return: 1 if there were commands to executed 0 otherwise
+ */
int w1_process_callbacks(struct w1_master *dev)
{
int ret = 0;