Re: [PATCHv2 4/6] dw_dmac: autoconfigure block_size or use platform data

Viresh Kumar
2012-09-21T15:30:10Z

On 21 September 2012 20:39, Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
> On Fri, 2012-09-21 at 19:30 +0530, viresh kumar wrote:
>> On Fri, Sep 21, 2012 at 5:35 PM, Andy Shevchenko
>> <andriy.shevchenko@linux.intel.com> wrote:
>> > diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c
>> > @@ -1385,6 +1375,7 @@ static int __devinit dw_probe(struct platform_device *pdev)
>>
>> > + /* get hardware configuration parameters */
>> > + if (autocfg)
>> > + max_blk_size = dma_readl(dw, MAX_BLK_SIZE);
>> > +
>>
>> Why don't you do above with the below ++ code
>>
>> > /* Calculate all channel mask before DMA setup */
>> > dw->all_chan_mask = (1 << nr_channels) - 1;
>> >
>> > @@ -1470,6 +1465,16 @@ static int __devinit dw_probe(struct platform_device *pdev)
>> > INIT_LIST_HEAD(&dwc->free_list);
>> >
>> > channel_clear_bit(dw, CH_EN, dwc->mask);
>> > +
>> > + /* hardware configuration */
>> > + if (autocfg)
>> > + /* Decode maximum block size for given channel. The
>> > + * stored 4 bit value represents blocks from 0x00 for 3
>> > + * up to 0x0a for 4095. */
>>
>> i.e. here?
> Because there is only one register, but we have loop for channels. Shall
> we read the same register as many times as amount of channels we have?

Obviously not :)
I misread the code.

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>