On 03-12-20, 04:46, Bard Liao wrote:
> From: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
>
> 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?
> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
> Reviewed-by: Rander Wang <rander.wang@xxxxxxxxxxxxxxx>
> Signed-off-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
> ---
> 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
--
~Vinod
