xref: /freebsd/sys/dev/ow/README.txt (revision 78d146160dc5339c9cdf7799551bcc442a6eb95b)
1*ae1f3df4SWarner LoshQuick Design Document for 1-wire bus
2*ae1f3df4SWarner Losh
3*ae1f3df4SWarner LoshIn new bus terms, 1-wire devices are attached to 1-wire buses (ow)
4*ae1f3df4SWarner Loshwhich are attached to a one wire bridge (owc).
5*ae1f3df4SWarner Losh
6*ae1f3df4SWarner LoshThe implementation follows the terminology used in the Maxim AN927
7*ae1f3df4SWarner LoshApplication note which defines the 1-wire bus as implemented for the
8*ae1f3df4SWarner LoshiButton product. This is considered to be the canonical definition of
9*ae1f3df4SWarner Loshthe 1-wire bus. This means that the 1-wire bridge will implement the
10*ae1f3df4SWarner Loshowll(9) interface. ow is one wire. ll is for Link Level to mirror the ISO
11*ae1f3df4SWarner Loshstack terminology used by AN927. The 1-wire bus is implemented in the ow(4)
12*ae1f3df4SWarner Loshdevice, which implements the own(9) interface (n for network, the layer
13*ae1f3df4SWarner Loshdescribed in the AN927). The presentation layer and above is the
14*ae1f3df4SWarner Loshresponsibility of the client device drivers to implement.
15*ae1f3df4SWarner Losh
16*ae1f3df4SWarner LoshClient drivers may only call the own(9) interface. The ow(4) driver
17*ae1f3df4SWarner Loshcalls the owll(9) interface and implements the own(9).
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