qemu /
qemu /
dd0b3271e55d4017fd6cd6b4feb4da6ea6c5d1d7 hw/i2c: pmbus: Page #255 is valid page for read requests.
Current implementation of the pmbus core driver treats the read request
for page 255 as invalid request and sets the invalid command bit (bit 7)
in the STATUS_CML register. As per the PMBus specification it is a valid
request.
Refer to the PMBus specification, revision 1.3.1, section 11.10 PAGE,
on the page 58:
"Setting the PAGE to FFh means that all subsequent comands are to be
applied to all outputs.
Some commands, such as READ_TEMPERATURE, may use a common sensor but
be available on all pages of a device. Such implementations are the
decision of each device manufacturer or are specified in a PMBus
Application Profile. Consult the manufacturer's documents or the
Application Profile Specification as needed."
For e.g.,
The VOUT_MODE is a valid command for page 255 for maxim 31785 device.
refer to Table 1. PMBus Command Codes on page 14 in the datasheet.
https://datasheets.maximintegrated.com/en/ds/MAX31785.pdf
Fixes: 38870253f1d1 ("hw/i2c: pmbus: fix error returns and guard against out of range accesses")
Signed-off-by: Maheswara Kurapati <quic_mkurapat@quicinc.com>
Signed-off-by: Jae Hyun Yoo <quic_jaehyoo@quicinc.com>
Reviewed-by: Titus Rwantare <titusr@google.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20220627154703.148943-4-quic_jaehyoo@quicinc.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
1 file changed