So far, divider_round_rate only considers the parent clock returned by clk_hw_get_parent. This works fine on clocks that have a single parents, this doesn't work on muxes, since we will only consider the first parent, while other parents may totally be able to provide a better combination. Clocks in that case cannot use divider_round_rate, so would have to come up with a very similar logic to work around it. Instead of having to do something like this, and duplicate that logic everywhere, create a divider_round_rate parent to allow caller to give an additional parameter for the parent clock to consider. Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx> --- drivers/clk/clk-divider.c | 26 ++++++++++++++++++-------- include/linux/clk-provider.h | 4 ++++ 2 files changed, 22 insertions(+), 8 deletions(-) diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c index 96386ffc8483..48750439b1cd 100644 --- a/drivers/clk/clk-divider.c +++ b/drivers/clk/clk-divider.c @@ -275,7 +275,8 @@ static int _next_div(const struct clk_div_table *table, int div, return div; } -static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, +static int clk_divider_bestdiv(struct clk_hw *hw, struct clk_hw *parent, + unsigned long rate, unsigned long *best_parent_rate, const struct clk_div_table *table, u8 width, unsigned long flags) @@ -314,8 +315,7 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, *best_parent_rate = parent_rate_saved; return i; } - parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw), - rate * i); + parent_rate = clk_hw_round_rate(parent, rate * i); now = DIV_ROUND_UP_ULL((u64)parent_rate, i); if (_is_best_div(rate, now, best, flags)) { bestdiv = i; @@ -326,22 +326,32 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate, if (!bestdiv) { bestdiv = _get_maxdiv(table, width, flags); - *best_parent_rate = clk_hw_round_rate(clk_hw_get_parent(hw), 1); + *best_parent_rate = clk_hw_round_rate(parent, 1); } return bestdiv; } -long divider_round_rate(struct clk_hw *hw, unsigned long rate, - unsigned long *prate, const struct clk_div_table *table, - u8 width, unsigned long flags) +long divider_round_rate_parent(struct clk_hw *hw, struct clk_hw *parent, + unsigned long rate, unsigned long *prate, + const struct clk_div_table *table, + u8 width, unsigned long flags) { int div; - div = clk_divider_bestdiv(hw, rate, prate, table, width, flags); + div = clk_divider_bestdiv(hw, parent, rate, prate, table, width, flags); return DIV_ROUND_UP_ULL((u64)*prate, div); } +EXPORT_SYMBOL_GPL(divider_round_rate_parent); + +long divider_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *prate, const struct clk_div_table *table, + u8 width, unsigned long flags) +{ + return divider_round_rate_parent(hw, clk_hw_get_parent(hw), rate, prate, + table, width, flags); +} EXPORT_SYMBOL_GPL(divider_round_rate); static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate, diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h index a428aec36ace..14102f783f64 100644 --- a/include/linux/clk-provider.h +++ b/include/linux/clk-provider.h @@ -412,6 +412,10 @@ extern const struct clk_ops clk_divider_ro_ops; unsigned long divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate, unsigned int val, const struct clk_div_table *table, unsigned long flags); +long divider_round_rate_parent(struct clk_hw *hw, struct clk_hw *parent, + unsigned long rate, unsigned long *prate, + const struct clk_div_table *table, + u8 width, unsigned long flags); long divider_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate, const struct clk_div_table *table, u8 width, unsigned long flags); -- git-series 0.8.11 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel