Wolfram Sang wrote:
On Tue, Jun 03, 2014 at 10:49:52AM +0200, Boris BREZILLON wrote:
The P2WI looks like an SMBus controller which only supports byte data
transfers. But, it differs from standard SMBus protocol on several
aspects:
- it supports only one slave device, and thus drop the address field
- it adds a parity bit every 8bits of data
- only one read access is required to read a byte (instead of a read
followed by a write access in standard SMBus protocol)
Minor quibble should be
"(instead of a write followed by a read access in standard SMBus
protocol)"
That being similar to EEPROM and other types of devices write internal
address followed by read access from internal address.
- there's no Ack bit after each byte transfer
This means this bus cannot be used to interface with standard SMBus
devices (the only known device to support this interface is the AXP221
PMIC).
Good description. Should be a comment at the top of the driver to spread
the word.
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