On Thu, Mar 23 2023, Dhruva Gole wrote: > buswidth and dtr fields in spi_mem_op are only valid when the > corresponding spi_mem_op phase has a non-zero length. For example,
Right. > SPI NAND core doesn't set buswidth when using SPI_MEM_OP_NO_ADDR > phase. > > Fix the dtr checks in set_protocol() to ignore empty spi_mem_op > phases, as checking for dtr field in empty phase will result in > false negatives. > > Signed-off-by: Apurva Nandan <a-nan...@ti.com> > Signed-off-by: Dhruva Gole <d-g...@ti.com> > --- > drivers/spi/cadence_qspi.c | 11 +++++++++-- > drivers/spi/cadence_qspi_apb.c | 9 ++++++++- > 2 files changed, 17 insertions(+), 3 deletions(-) > > diff --git a/drivers/spi/cadence_qspi.c b/drivers/spi/cadence_qspi.c > index c7f10c501320..a858a62888e4 100644 > --- a/drivers/spi/cadence_qspi.c > +++ b/drivers/spi/cadence_qspi.c > @@ -362,8 +362,15 @@ static bool cadence_spi_mem_supports_op(struct spi_slave > *slave, > { > bool all_true, all_false; > > - all_true = op->cmd.dtr && op->addr.dtr && op->dummy.dtr && > - op->data.dtr; > + /* > + * op->dummy.dtr is required for converting nbytes into ncycles. > + * Also, don't check the dtr field of the op phase having zero nbytes. > + */ > + all_true = op->cmd.dtr && > + (!op->addr.nbytes || op->addr.dtr) && > + (!op->dummy.nbytes || op->dummy.dtr) && > + (!op->data.nbytes || op->data.dtr); Looks good! > + > all_false = !op->cmd.dtr && !op->addr.dtr && !op->dummy.dtr && > !op->data.dtr; Since we treat DTR as "do not care" when the phase does not exist, you should check for that here as well. What if someone _sets_ DTR for a field with nbytes == 0? This check would fail. Since no one reasonable should do this, I will not insist upon this. Fine by me if you don't do this. Your choice. > > diff --git a/drivers/spi/cadence_qspi_apb.c b/drivers/spi/cadence_qspi_apb.c > index 21fe2e655c5f..2b04b58124a5 100644 > --- a/drivers/spi/cadence_qspi_apb.c > +++ b/drivers/spi/cadence_qspi_apb.c > @@ -120,7 +120,14 @@ static int cadence_qspi_set_protocol(struct > cadence_spi_priv *priv, > { > int ret; > > - priv->dtr = op->data.dtr && op->cmd.dtr && op->addr.dtr; > + /* > + * For an op to be DTR, cmd phase along with every other non-empty > + * phase should have dtr field set to 1. If an op phase has zero > + * nbytes, ignore its dtr field; otherwise, check its dtr field. > + */ > + priv->dtr = op->cmd.dtr && > + (!op->addr.nbytes || op->addr.dtr) && > + (!op->data.nbytes || op->data.dtr); Why not check dummy? Since supports_op() already checks that _all_ or _none_ of the fields are DTR, you can get away with just checking for op->cmd.dtr here (do add a comment here or it can be a bit confusing). BTW, I think it would be better if you get rid of cadence_qspi_set_protocol() entirely. I see no point in carrying the state around. Wherever you use priv->dtr or priv->inst_width, etc. you also have access to the spi_mem_op. You can derive that information from the op. Something to fix when you have some free time on your hands. Will make the driver a bit simpler. > > ret = cadence_qspi_buswidth_to_inst_type(op->cmd.buswidth); > if (ret < 0) > -- > 2.25.1 > -- Regards, Pratyush Yadav Amazon Development Center Germany GmbH Krausenstr. 38 10117 Berlin Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss Eingetragen am Amtsgericht Charlottenburg unter HRB 149173 B Sitz: Berlin Ust-ID: DE 289 237 879