Re: [PATCH v3 5/6] ARM: davinci: Add support for PRUSS on DA850

From: Matt Porter
Date: Thu Oct 04 2012 - 12:35:09 EST


On Thu, Oct 04, 2012 at 05:52:45PM +0530, Sekhar Nori wrote:
> On 10/3/2012 8:25 PM, Matt Porter wrote:
> > +static struct clk pruss_clk = {
> > + .name = "pruss",
> > + .parent = &pll0_sysclk2,
> > + .lpsc = DA8XX_LPSC0_PRUSS,
> > +};
> > +
> > static struct clk uart0_clk = {
> > .name = "uart0",
> > .parent = &pll0_sysclk2,
> > @@ -378,6 +384,7 @@ static struct clk_lookup da850_clks[] = {
> > CLK(NULL, "tptc1", &tptc1_clk),
> > CLK(NULL, "tpcc1", &tpcc1_clk),
> > CLK(NULL, "tptc2", &tptc2_clk),
> > + CLK(NULL, "pruss", &pruss_clk),
>
> This is actually incorrect since we should use device name rather than
> con_id for matching the clock. If there is just one clock that the
> driver needs, connection id should be NULL. Looking at the driver now,
> the clk_get() call seems to pass a valid device pointer. So, I wonder
> how you are able to look up the clock even with a NULL device name.

I doublechecked the clk_get() find implentation to confirm that I indeed
did get lucky here. Since pruss has only one instance and the clk_find()
implementation looks for the best found match, it's able to find the
clock just by the con_id, though it's not the "best possible" match in
the find implementation...it's the "best found" match.. As you noted,
this is incorrect though for a clock expected to be used from a driver
context so I will address this in the update.

-Matt
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