[PATCH 2/2] SPI: SAMSUNG: Bug fix for SPI with different FIFO level

[padma venkat]

Hi,

On Thu, Jun 30, 2011 at 12:38 PM, Jassi Brar <jassisinghbrar at gmail.com> wrote:
> On Thu, Jun 30, 2011 at 6:08 PM, Padmavathi Venna <padma.v at samsung.com> wrote:
>> Fixed the bug in transmission status check for 64 bytes FIFO
>> level.
>>
>> Signed-off-by: Padmavathi Venna <padma.v at samsung.com>
>> ---
>>  drivers/spi/spi_s3c64xx.c |    4 +---
>>  1 files changed, 1 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/spi/spi_s3c64xx.c b/drivers/spi/spi_s3c64xx.hc
>> index 795828b..8945e20 100644
>> --- a/drivers/spi/spi_s3c64xx.c
>> +++ b/drivers/spi/spi_s3c64xx.c
>> @@ -116,9 +116,7 @@
>>                                        (((i)->fifo_lvl_mask + 1))) \
>>                                        ? 1 : 0)
>>
>> -#define S3C64XX_SPI_ST_TX_DONE(v, i) ((((v) >> (i)->rx_lvl_offset) & \
>> -                                       (((i)->fifo_lvl_mask + 1) << 1)) \
>> -                                       ? 1 : 0)
>> +#define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & (1 << (i)->tx_st_done)) ? 1 : 0)
>
> IIRC the macro is already designed to deduct tx-done levels from other fields.
> Could you please _explain_ with one example where it fails ? It is
> difficult to see without
> numbers.
The existing macro fails for following scenarios.
1) S5P64X0 channel 1
2) S5PV210 channel 1
3) S5PV310 channel 1 and channel 2

The FIFO data level supported in the above SoCs either 64 or 256
bytes depending on the channel. Because of this the TX_DONE
is the 25 bit in the status register.

The existing macro works for the following scenarios
1) S3C6410 all channels
2) S5PC100 all channels

The FIFO data level supported in the above SoCs 64 bytes
on all the channels. Because of this the TX_DONE is the 21 bit
in the status register.

So when we use the existing macro for the non-working SoCs
it is not anding with the TX_DONE bit but it is only anding the bits
earlier to TX_DONE bit.

>
> Thanks,
> -Jassi
> --
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