[PATCH 1/3] i2c: add DMA support for freescale i2c driver
Shawn Guo
shawn.guo at linaro.org
Thu Feb 27 21:23:52 EST 2014
On Fri, Feb 28, 2014 at 10:13:02AM +0800, Shawn Guo wrote:
> On Thu, Feb 27, 2014 at 09:39:35PM +0100, Marek Vasut wrote:
> > > @@ -193,6 +216,7 @@ static const struct imx_i2c_hwdata imx1_i2c_hwdata = {
> > > .ndivs = ARRAY_SIZE(imx_i2c_clk_div),
> > > .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C,
> > > .i2cr_ien_opcode = I2CR_IEN_OPCODE_1,
> > > + .has_dma_support = false,
> > >
> > > };
> > >
> > > @@ -203,6 +227,7 @@ static const struct imx_i2c_hwdata imx21_i2c_hwdata =
> > > { .ndivs = ARRAY_SIZE(imx_i2c_clk_div),
> > > .i2sr_clr_opcode = I2SR_CLR_OPCODE_W0C,
> > > .i2cr_ien_opcode = I2CR_IEN_OPCODE_1,
> > > + .has_dma_support = false,
> > >
> > > };
> > >
> > > @@ -213,6 +238,7 @@ static struct imx_i2c_hwdata vf610_i2c_hwdata = {
> > > .ndivs = ARRAY_SIZE(vf610_i2c_clk_div),
> > > .i2sr_clr_opcode = I2SR_CLR_OPCODE_W1C,
> > > .i2cr_ien_opcode = I2CR_IEN_OPCODE_0,
> > > + .has_dma_support = true,
> >
> > So why exactly don't we have a DT prop for determining whether the controller
> > has DMA support ?
>
> Using DMA or PIO is a decision that should be made by driver on its own,
> not device tree.
Sorry. I misunderstood it. Yes, we can look at the DT property 'dmas'
to know if the controller has DMA capability.
Shawn
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