Re: [PATCH 3/3] usb: musb: musb_cppi41: Handle ISOCH differentlyand not use the hrtimer.

[George Cherian]

On 1/24/2014 11:16 PM, Sergei Shtylyov wrote:
> Hello.
>
> On 24-01-2014 18:14, George Cherian wrote:
>
> > In case of ISOCH transfers the hrtimer workaround for the hardware issue
> > is not very reliable. Instead of checking musb_is_tx_fifo_empty() in 
> > hrtimer
> > routine, schedule a completion work and check the same in completion 
> > work.
>
> > Signed-off-by: George Cherian <george.cherian@xxxxxx>
> > ---
> >   drivers/usb/musb/musb_cppi41.c | 54 
> > +++++++++++++++++++++++++++++++++++++++++-
> >   1 file changed, 53 insertions(+), 1 deletion(-)
>
> > diff --git a/drivers/usb/musb/musb_cppi41.c 
> > b/drivers/usb/musb/musb_cppi41.c
> > index 39ee516..8075562 100644
> > --- a/drivers/usb/musb/musb_cppi41.c
> > +++ b/drivers/usb/musb/musb_cppi41.c
> [...]
> > @@ -165,6 +178,32 @@ static void cppi41_trans_done(struct 
> > cppi41_dma_channel *cppi41_channel)
> >       }
> >   }
> >
> > +static void cppi_trans_done_work(struct work_struct *work)
> > +{
> > +    unsigned long flags;
> > +    struct cppi41_dma_channel *cppi41_channel =
> > +        container_of(work, struct cppi41_dma_channel, dma_completion);
> > +    struct cppi41_dma_controller *controller = 
> > cppi41_channel->controller;
> > +    struct musb *musb = controller->musb;
> > +    struct musb_hw_ep *hw_ep = cppi41_channel->hw_ep;
> > +    bool empty;
> > +
> > +    if (!cppi41_channel->is_tx && is_isoc(hw_ep, 1)) {
> > +            spin_lock_irqsave(&musb->lock, flags);
> > +            cppi41_trans_done(cppi41_channel);
> > +            spin_unlock_irqrestore(&musb->lock, flags);
>
>    This *if* arm is clearly over-indented by one tab. Compare with 
> below *else* arm.

Will Fix in v2


> > +    } else {
> > +        empty = musb_is_tx_fifo_empty(hw_ep);
> > +        if (empty) {
> > +            spin_lock_irqsave(&musb->lock, flags);
> > +            cppi41_trans_done(cppi41_channel);
> > +            spin_unlock_irqrestore(&musb->lock, flags);
> > +        } else {
> > + schedule_work(&cppi41_channel->dma_completion);
> > +        }
> > +    }
> > +}
> > +
>
> WBR, Sergei


--
-George

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