diff --git a/drivers/clk/renesas/clk-div6.c b/drivers/clk/renesas/clk-div6.c index 3af65ef5690e..a9ac2a83c1d0 100644 --- a/drivers/clk/renesas/clk-div6.c +++ b/drivers/clk/renesas/clk-div6.c @@ -103,10 +103,39 @@ static unsigned int cpg_div6_clock_calc_div(unsigned long rate, static int cpg_div6_clock_determine_rate(struct clk_hw *hw, struct clk_rate_request *req) { - unsigned int div = cpg_div6_clock_calc_div(req->rate, - req->best_parent_rate); + unsigned long prate, calc_rate, diff, best_rate, best_prate; + unsigned int num_parents = clk_hw_get_num_parents(hw); + struct clk_hw *parent, *best_parent = NULL; + unsigned long min_diff = ULONG_MAX; + unsigned int i, div; - req->rate = req->best_parent_rate / div; + for (i = 0; i < num_parents; i++) { + parent = clk_hw_get_parent_by_index(hw, i); + if (!parent) + continue; + + prate = clk_hw_get_rate(parent); + if (!prate) + continue; + + div = cpg_div6_clock_calc_div(req->rate, prate); + calc_rate = prate / div; + diff = calc_rate > req->rate ? calc_rate - req->rate + : req->rate - calc_rate; + if (diff < min_diff) { + best_rate = calc_rate; + best_parent = parent; + best_prate = prate; + min_diff = diff; + } + } + + if (!best_parent) + return -EINVAL; + + req->best_parent_rate = best_prate; + req->best_parent_hw = best_parent; + req->rate = best_rate; return 0; }