Re: [PATCH v7 2/3] clk: introduce the common clock framework

On Mon, Mar 19, 2012 at 04:52:05PM +0530, Rajendra Nayak wrote:

Hi Mike,

...

+/*

• • calculate the new rates returning the topmost clock that has to be
• • changed.
• */

+static struct clk *clk_calc_new_rates(struct clk *clk, unsigned long rate) +{

• struct clk *top = clk;
• unsigned long best_parent_rate = clk->parent->rate;

Shouldn't you check for a valid parent before dereferencing it? A clk_set_rate() on a root clock might throw up some issues otherwise.

Yes, should be checked.

...

• unsigned long new_rate;
• if (!clk->ops->round_rate&& !(clk->flags& CLK_SET_RATE_PARENT)) {

• clk->new_rate = clk->rate;
  

• return NULL;
  

So does this mean a clk_set_rate() fails for a clk which does not have a valid .round_rate and does not have a CLK_SET_RATE_PARENT flag set? I was thinking this could do a.. clk->new_rate = rate; top = clk; goto out; ..instead.

The core should make sure that either both set_rate and round_rate are present or none of them.

Sascha