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clk: at91: replace prog clk round_rate with determine_rate

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Implement the determine_rate callback to choose the best parent clk that
fulfills the requested rate.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
This commit is contained in:
Boris BREZILLON 2014-03-11 10:00:32 +01:00 committed by Mike Turquette
parent 843bad8361
commit 419f612932
1 changed files with 30 additions and 30 deletions
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60
drivers/clk/at91/clk-programmable.c
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@ -102,40 +102,40 @@ static unsigned long clk_programmable_recalc_rate(struct clk_hw *hw,
return parent_rate >> prog->pres;
}
static long clk_programmable_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *parent_rate)
static long clk_programmable_determine_rate(struct clk_hw *hw,
unsigned long rate,
unsigned long *best_parent_rate,
struct clk **best_parent_clk)
{
unsigned long best_rate = *parent_rate;
unsigned long best_diff;
unsigned long new_diff;
unsigned long cur_rate;
int shift = shift;
struct clk *parent = NULL;
long best_rate = -EINVAL;
unsigned long parent_rate;
unsigned long tmp_rate;
int shift;
int i;
if (rate > *parent_rate)
return *parent_rate;
else
best_diff = *parent_rate - rate;
for (i = 0; i < __clk_get_num_parents(hw->clk); i++) {
parent = clk_get_parent_by_index(hw->clk, i);
if (!parent)
continue;
if (!best_diff)
return best_rate;
for (shift = 1; shift < PROG_PRES_MASK; shift++) {
cur_rate = *parent_rate >> shift;
if (cur_rate > rate)
new_diff = cur_rate - rate;
else
new_diff = rate - cur_rate;
if (!new_diff)
return cur_rate;
if (new_diff < best_diff) {
best_diff = new_diff;
best_rate = cur_rate;
parent_rate = __clk_get_rate(parent);
for (shift = 0; shift < PROG_PRES_MASK; shift++) {
tmp_rate = parent_rate >> shift;
if (tmp_rate <= rate)
break;
}
if (rate > cur_rate)
if (tmp_rate > rate)
continue;
if (best_rate < 0 || (rate - tmp_rate) < (rate - best_rate)) {
best_rate = tmp_rate;
*best_parent_rate = parent_rate;
*best_parent_clk = parent;
}
if (!best_rate)
break;
}
@ -228,7 +228,7 @@ static const struct clk_ops programmable_ops = {
.prepare = clk_programmable_prepare,
.is_prepared = clk_programmable_is_ready,
.recalc_rate = clk_programmable_recalc_rate,
.round_rate = clk_programmable_round_rate,
.determine_rate = clk_programmable_determine_rate,
.get_parent = clk_programmable_get_parent,
.set_parent = clk_programmable_set_parent,
.set_rate = clk_programmable_set_rate,