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authorQuentin Schulz <quentin.schulz@free-electrons.com>2017-08-10 08:34:04 +0200
committerStephen Boyd <sboyd@codeaurora.org>2017-09-01 15:46:53 -0700
commit8a8f4bf0c48055f0648b5449f4685b6cd0fc1c85 (patch)
tree925f18e24acecef715ed485e7a5f76d074ac13ad /drivers/clk
parent0865805d82d4c822647ee35ab2629c48cc40706b (diff)
downloadlinux-8a8f4bf0c48055f0648b5449f4685b6cd0fc1c85.tar.bz2
clk: at91: clk-generated: create function to find best_diff
The way to find the best_diff and do the appropriate process afterwards can be re-used. This patch prepares the driver for an upcoming patch that will allow clk_generated to determine the rate of the audio_pll. Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com> Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Diffstat (limited to 'drivers/clk')
-rw-r--r--drivers/clk/at91/clk-generated.c41
1 files changed, 27 insertions, 14 deletions
diff --git a/drivers/clk/at91/clk-generated.c b/drivers/clk/at91/clk-generated.c
index ef4b4e03de04..7260e498e059 100644
--- a/drivers/clk/at91/clk-generated.c
+++ b/drivers/clk/at91/clk-generated.c
@@ -99,15 +99,36 @@ clk_generated_recalc_rate(struct clk_hw *hw,
return DIV_ROUND_CLOSEST(parent_rate, gck->gckdiv + 1);
}
+static void clk_generated_best_diff(struct clk_rate_request *req,
+ struct clk_hw *parent,
+ unsigned long parent_rate, u32 div,
+ int *best_diff, long *best_rate)
+{
+ unsigned long tmp_rate;
+ int tmp_diff;
+
+ if (!div)
+ tmp_rate = parent_rate;
+ else
+ tmp_rate = parent_rate / div;
+ tmp_diff = abs(req->rate - tmp_rate);
+
+ if (*best_diff < 0 || *best_diff > tmp_diff) {
+ *best_rate = tmp_rate;
+ *best_diff = tmp_diff;
+ req->best_parent_rate = parent_rate;
+ req->best_parent_hw = parent;
+ }
+}
+
static int clk_generated_determine_rate(struct clk_hw *hw,
struct clk_rate_request *req)
{
struct clk_generated *gck = to_clk_generated(hw);
struct clk_hw *parent = NULL;
long best_rate = -EINVAL;
- unsigned long tmp_rate, min_rate;
+ unsigned long min_rate;
int best_diff = -1;
- int tmp_diff;
int i;
for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
@@ -125,18 +146,10 @@ static int clk_generated_determine_rate(struct clk_hw *hw,
continue;
div = DIV_ROUND_CLOSEST(parent_rate, req->rate);
- if (!div)
- tmp_rate = parent_rate;
- else
- tmp_rate = parent_rate / div;
- tmp_diff = abs(req->rate - tmp_rate);
-
- if (best_diff < 0 || best_diff > tmp_diff) {
- best_rate = tmp_rate;
- best_diff = tmp_diff;
- req->best_parent_rate = parent_rate;
- req->best_parent_hw = parent;
- }
+
+ clk_generated_best_diff(req, parent, parent_rate, div,
+ &best_diff, &best_rate);
+
if (!best_diff)
break;