Re: [PATCH v3 1/2] i2c: add DMA support for freescale i2c driver

From: Marek Vasut
Date: Wed Mar 26 2014 - 02:26:56 EST


On Wednesday, March 26, 2014 at 06:56:34 AM, Yao Yuan wrote:
> On Wednesday, March 26, 2014 at 11:43:27 AM, Marek Vasut wrote:
> > On Wednesday, March 26, 2014 at 04:08:27 AM, Yao Yuan wrote:
> >
> > [...]
> >
> > > > > + i2c_imx->use_dma = false;
> > > > > + } else if (i2c_imx_dma_request(i2c_imx, (dma_addr_t)phy_addr))
> >
> > {
> >
> > > > > + dev_info(&pdev->dev,
> > > > > + "can't request dma chan, faild use dma.
\n");
> > > > > + i2c_imx->use_dma = false;
> > > > > + } else {
> > > > > + i2c_imx->use_dma = true;
> > > > > + }
> > > >
> > > > Can you not just check if i2c_imx->dma is valid pointer or NULL
> >
> > pointer ?
> >
> > > > Then you won't need a separate variable, for this purpose ... right ?
> > >
> > > Sorry and I think what I know is just to check whether it is NULL.
> > > Then for the second question, maybe there are some other ways, But I
> > > think it is more tidy and easier understanding for using a separate
> > > variable, for this purpose.
> >
> > You are just wasting space and duplicating data, unless I am wrong.
>
> Well, Do you have a better idea? Although I think it's necessary.

I think we disconnected here, sorry. Why can you not use (i2c_imx->dma != NULL)
instead of (i2c_imx->use_dma == true) please ?

Best regards,
Marek Vasut
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