diff options
| author | Quentin Schulz <quentin.schulz@free-electrons.com> | 2017-08-10 08:34:04 +0200 |
|---|---|---|
| committer | Stephen Boyd <sboyd@codeaurora.org> | 2017-09-02 00:46:53 +0200 |
| commit | 8a8f4bf0c48055f0648b5449f4685b6cd0fc1c85 (patch) | |
| tree | 925f18e24acecef715ed485e7a5f76d074ac13ad /drivers/clk | |
| parent | clk: at91: add audio pll clock drivers (diff) | |
| download | linux-8a8f4bf0c48055f0648b5449f4685b6cd0fc1c85.tar.xz linux-8a8f4bf0c48055f0648b5449f4685b6cd0fc1c85.zip | |
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.c | 41 |
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; |