Messages in this thread | | | Subject | Re: [PATCH 1/7] soundwire: bus: use sdw_update_no_pm when initializing a device | From | Pierre-Louis Bossart <> | Date | Sat, 5 Dec 2020 08:59:01 -0600 |
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Thanks for the review Vinod.
On 12/5/20 1:45 AM, Vinod Koul wrote: > On 03-12-20, 04:46, Bard Liao wrote: >> From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> >> >> When a Slave device is resumed, it may resume the bus and restart the >> enumeration. During that process, we absolutely don't want to call >> regular read/write routines which will wait for the resume to >> complete, otherwise a deadlock occurs. >> >> Fixes: 60ee9be25571 ('soundwire: bus: add PM/no-PM versions of read/write functions') > > Change looks okay, but not sure why this is a fix for adding no pm > version?
when we added the no_pm version, we missed the two cases below where sdw_update() was used and that creates a deadlock. To me that's a conceptual bug, we didn't fully use the no_pm versions, hence the Fixes tag.
It's ok to remove the tag if you don't think it's useful/relevant, what matters is that we agree on the content.
>> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> >> Reviewed-by: Rander Wang <rander.wang@linux.intel.com> >> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> >> --- >> drivers/soundwire/bus.c | 16 ++++++++++++++-- >> 1 file changed, 14 insertions(+), 2 deletions(-) >> >> diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c >> index d1e8c3a54976..60c42508c6c6 100644 >> --- a/drivers/soundwire/bus.c >> +++ b/drivers/soundwire/bus.c >> @@ -489,6 +489,18 @@ sdw_read_no_pm(struct sdw_slave *slave, u32 addr) >> return buf; >> } >> >> +static int sdw_update_no_pm(struct sdw_slave *slave, u32 addr, u8 mask, u8 val) >> +{ >> + int tmp; >> + >> + tmp = sdw_read_no_pm(slave, addr); >> + if (tmp < 0) >> + return tmp; >> + >> + tmp = (tmp & ~mask) | val; >> + return sdw_write_no_pm(slave, addr, tmp); >> +} >> + >> /** >> * sdw_nread() - Read "n" contiguous SDW Slave registers >> * @slave: SDW Slave >> @@ -1256,7 +1268,7 @@ static int sdw_initialize_slave(struct sdw_slave *slave) >> val = slave->prop.scp_int1_mask; >> >> /* Enable SCP interrupts */ >> - ret = sdw_update(slave, SDW_SCP_INTMASK1, val, val); >> + ret = sdw_update_no_pm(slave, SDW_SCP_INTMASK1, val, val); >> if (ret < 0) { >> dev_err(slave->bus->dev, >> "SDW_SCP_INTMASK1 write failed:%d\n", ret); >> @@ -1271,7 +1283,7 @@ static int sdw_initialize_slave(struct sdw_slave *slave) >> val = prop->dp0_prop->imp_def_interrupts; >> val |= SDW_DP0_INT_PORT_READY | SDW_DP0_INT_BRA_FAILURE; >> >> - ret = sdw_update(slave, SDW_DP0_INTMASK, val, val); >> + ret = sdw_update_no_pm(slave, SDW_DP0_INTMASK, val, val); >> if (ret < 0) >> dev_err(slave->bus->dev, >> "SDW_DP0_INTMASK read failed:%d\n", ret); >> -- >> 2.17.1 >
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