Re: [PATCH] spi/omap2_mcspi: disable and enable chan between each SPI transfer

[Grant Likely <grant.likely@secretlab.ca>]

On Fri, Jun 25, 2010 at 6:05 AM, jason <jason77.wang@gmail.com> wrote:
> roman.tereshonkov@nokia.com wrote:
>>
>>
>>
>
> [snip]
>>>
>>> -----Original Message-----
>>>
>>>                                        }
>>>                                        c = 0;
>>> -                               } else if (c == 0 && tx == NULL) {
>>> -                                       omap2_mcspi_set_enable(spi, 0);
>>>                                }
>>>
>>>                                *rx++ = __raw_readl(rx_reg);
>>>
>>
>> Why do you do this?
>> Reading the last word from the shift register buffer leads to the
>> receiving new data to the buffer.
>> The channel needs to be disabled before the last word reading.
>>
>>
>>
>
> Yes, you are right. If this patch can be accepted, i will remove those
> changes in the V2 patch.
> Please see my email replying grant likely's questions.

Hi Jason.

I'm assuming I can ignore this patch and wait for your V2.  I'll still
want an ack from other omap spi users before I apply it though.

g.

>
> Thanks,
> Jason.
>>
>>
>>>
>>> @@ -646,7 +641,7 @@ omap2_mcspi_txrx_pio(struct spi_device *spi, struct
>>> spi_transfer *xfer)
>>>                        dev_err(&spi->dev, "EOT timed out\n");
>>>        }
>>> out:
>>> -       omap2_mcspi_set_enable(spi, 1);
>>> +       omap2_mcspi_set_enable(spi, 0);
>>>        return count - c;
>>> }
>>>
>>> @@ -894,7 +889,6 @@ static void omap2_mcspi_work(struct work_struct
>>> *work)
>>>                cs = spi->controller_state;
>>>                cd = spi->controller_data;
>>>
>>> -               omap2_mcspi_set_enable(spi, 1);
>>>                list_for_each_entry(t, &m->transfers, transfer_list) {
>>>                        if (t->tx_buf == NULL && t->rx_buf == NULL &&
>>> t->len) {
>>>                                status = -EINVAL;
>>> @@ -931,6 +925,8 @@ static void omap2_mcspi_work(struct work_struct
>>> *work)
>>>
>>>                        mcspi_write_chconf0(spi, chconf);
>>>
>>> +                       omap2_mcspi_set_enable(spi, 1);
>>> +
>>>                        if (t->len) {
>>>                                unsigned        count;
>>>
>>> --
>>> 1.5.6.5
>>>
>>>
>>>
>
>



-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.