On Wed, 22 Jun 2022 at 10:29, Jae Hyun Yoo <quic_jaeh...@quicinc.com> wrote: > > From: Maheswara Kurapati <quic_mkura...@quicinc.com> > > 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 socuments or the Applicatin Profile Specification as > needed." > Thanks for this, the copy of the spec I used was older.
> 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_mkura...@quicinc.com> > --- > hw/i2c/pmbus_device.c | 1 - > 1 file changed, 1 deletion(-) > > diff --git a/hw/i2c/pmbus_device.c b/hw/i2c/pmbus_device.c > index 62885fa6a15e..7db3343a83b6 100644 > --- a/hw/i2c/pmbus_device.c > +++ b/hw/i2c/pmbus_device.c > @@ -291,7 +291,6 @@ static uint8_t pmbus_receive_byte(SMBusDevice *smd) > qemu_log_mask(LOG_GUEST_ERROR, > "%s: tried to read from all pages\n", > __func__); > - pmbus_cml_error(pmdev); > } else if (pmdev->page > pmdev->num_pages - 1) { > qemu_log_mask(LOG_GUEST_ERROR, > "%s: page %d is out of range\n", > -- > 2.25.1 > Please also update the stale comment just above, since this is now specified behaviour. Reviewed-by: Titus Rwantare <tit...@google.com>
