From mboxrd@z Thu Jan 1 00:00:00 1970 From: moinejf@free.fr (Jean-Francois Moine) Date: Wed, 30 Mar 2016 19:47:40 +0200 Subject: [PATCH v2] clk: sunxi: Accept a greater rate when setting a parent clock Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org The best rate of a clock may be a bit greater than the requested one. In such a case, the rate setting from a child clock was rejected. This patch fixes the problem searching a 'best rate' instead of a 'fastest rate <= rate'. Signed-off-by: Jean-Francois Moine --- drivers/clk/sunxi/clk-factors.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/clk/sunxi/clk-factors.c b/drivers/clk/sunxi/clk-factors.c index ddefe96..c8e2f29 100644 --- a/drivers/clk/sunxi/clk-factors.c +++ b/drivers/clk/sunxi/clk-factors.c @@ -95,9 +95,10 @@ static int clk_factors_determine_rate(struct clk_hw *hw, struct clk_factors *factors = to_clk_factors(hw); struct clk_hw *parent, *best_parent = NULL; int i, num_parents; - unsigned long parent_rate, best = 0, child_rate, best_child_rate = 0; + unsigned long parent_rate, best = 0, child_rate, best_child_rate; + unsigned long d_rate, best_d_rate = ~0ul; - /* find the parent that can help provide the fastest rate <= rate */ + /* find the parent that can help provide the best rate */ num_parents = clk_hw_get_num_parents(hw); for (i = 0; i < num_parents; i++) { struct factors_request factors_req = { @@ -116,10 +117,18 @@ static int clk_factors_determine_rate(struct clk_hw *hw, factors->get_factors(&factors_req); child_rate = factors_req.rate; - if (child_rate <= req->rate && child_rate > best_child_rate) { + if (child_rate >= req->rate) + d_rate = child_rate - req->rate; + else + d_rate = req->rate - child_rate; + + if (d_rate < best_d_rate) { best_parent = parent; best = parent_rate; best_child_rate = child_rate; + if (d_rate == 0) + break; + best_d_rate = d_rate; } } -- 2.8.0