[PATCH 3/9] ARM: edma: Add function to manually trigger an EDMA channel

[Fernandes, Joel]

On Jul 31, 2013, at 12:23 AM, "Nori, Sekhar" <nsekhar at ti.com> wrote:

> On Wednesday 31 July 2013 10:00 AM, Joel Fernandes wrote:
>> On 07/30/2013 12:18 AM, Sekhar Nori wrote:
>>> On Monday 29 July 2013 06:59 PM, Joel Fernandes wrote:
>>>> Manual trigger for events missed as a result of splitting a
>>>> scatter gather list and DMA'ing it in batches. Add a helper
>>>> function to trigger a channel incase any such events are missed.
>>>> 
>>>> Signed-off-by: Joel Fernandes <joelf at ti.com>
>>>> ---
>>>> arch/arm/common/edma.c             |   21 +++++++++++++++++++++
>>>> include/linux/platform_data/edma.h |    2 ++
>>>> 2 files changed, 23 insertions(+)
>>>> 
>>>> diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c
>>>> index 3567ba1..10995b2 100644
>>>> --- a/arch/arm/common/edma.c
>>>> +++ b/arch/arm/common/edma.c
>>>> @@ -1236,6 +1236,27 @@ void edma_resume(unsigned channel)
>>>> }
>>>> EXPORT_SYMBOL(edma_resume);
>>>> 
>>>> +int edma_manual_trigger(unsigned channel)
>>> 
>>> edma_trigger_channel() maybe? Brings consistency with
>>> edma_alloc_channel() edma_free_channel() etc.
>> 
>> Ok, sure.
>> 
>>> 
>>>> +{
>>>> +    unsigned ctlr;
>>>> +    int j;
>>>> +    unsigned int mask;
>>>> +
>>>> +    ctlr = EDMA_CTLR(channel);
>>>> +    channel = EDMA_CHAN_SLOT(channel);
>>>> +    mask = BIT(channel & 0x1f);
>>>> +
>>>> +    j = channel >> 5;
>>>> +
>>>> +    /* EDMA channels without event association */
>>> 
>>> May be actually check for no-event association before you trigger in
>>> software? You can do that by looking at unused channel list, no?
>> 
>> But, we want to trigger whether there is event association or not in
>> this function. For ex, MMC has event associated but still this function
>> is used to trigger event for it.
> 
> Okay, just drop the misleading comment then.

Ok, will do.

Thanks,

-Joel

> 
> Regards,
> Sekhar