Diffstat (limited to 'Documentation/w1')
1 files changed, 15 insertions, 3 deletions
diff --git a/Documentation/w1/w1.generic b/Documentation/w1/w1.generic
index f937fbe1cacb..4c6509dd4789 100644
@@ -27,8 +27,19 @@ When a w1 master driver registers with the w1 subsystem, the following occurs:
When a device is found on the bus, w1 core checks if driver for it's family is
loaded. If so, the family driver is attached to the slave.
-If there is no driver for the family, a simple sysfs entry is created
-for the slave device.
+If there is no driver for the family, default one is assigned, which allows to perform
+almost any kind of operations. Each logical operation is a transaction
+in nature, which can contain several (two or one) low-level operations.
+Let's see how one can read EEPROM context:
+1. one must write control buffer, i.e. buffer containing command byte
+and two byte address. At this step bus is reset and appropriate device
+is selected using either W1_SKIP_ROM or W1_MATCH_ROM command.
+Then provided control buffer is being written to the wire.
+2. reading. This will issue reading eeprom response.
+It is possible that between 1. and 2. w1 master thread will reset bus for searching
+and slave device will be even removed, but in this case 0xff will
+be read, since no device was selected.
W1 device families
@@ -89,4 +100,5 @@ driver - (standard) symlink to the w1 driver
name - the device name, usually the same as the directory name
w1_slave - (optional) a binary file whose meaning depends on the
+rw - (optional) created for slave devices which do not have
+ appropriate family driver. Allows to read/write binary data.