clk: sprd: composite: Simplify determine_rate implementation

The sprd_div_helper_round_rate() function calls divider_round_rate()
which calls divider_round_rate_parent() which calls
divider_determine_rate(). This call chain converts back and forth from
the rate request structure to make a determine_rate clk_op fit with a
round_rate clk_op. Simplify the code here by directly calling
divider_determine_rate() instead.

This fixes a smatch warning where an unsigned long is compared to less
than zero, which is impossible. This makes sprd_div_helper_round_rate()
unnecessary as well so simply remove it and fold it into the only caller
left.

Reported-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Closes: https://lore.kernel.org/r/45fdc54e-7ab6-edd6-d55a-473485608473@oracle.com
Cc: Maxime Ripard <maxime@cerno.tech>
Fixes: 302d2f836d ("clk: sprd: composite: Switch to determine_rate")
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20230613195443.1555132-1-sboyd@kernel.org
Reviewed-by: Maxime Ripard <mripard@kernel.org>

drivers/clk/sprd/composite.c

@@ -13,15 +13,8 @@ static int sprd_comp_determine_rate(struct clk_hw *hw,
 				    struct clk_rate_request *req)
 {
 	struct sprd_comp *cc = hw_to_sprd_comp(hw);
-	unsigned long rate;
 
-	rate = sprd_div_helper_round_rate(&cc->common, &cc->div,
-					  req->rate, &req->best_parent_rate);
-	if (rate < 0)
-		return rate;
-
-	req->rate = rate;
-	return 0;
+	return divider_determine_rate(hw, req, NULL, cc->div.width, 0);
 }
 
 static unsigned long sprd_comp_recalc_rate(struct clk_hw *hw,

drivers/clk/sprd/div.c

@@ -9,23 +9,13 @@
 
 #include "div.h"
 
-long sprd_div_helper_round_rate(struct sprd_clk_common *common,
-				const struct sprd_div_internal *div,
-				unsigned long rate,
-				unsigned long *parent_rate)
-{
-	return divider_round_rate(&common->hw, rate, parent_rate,
-				  NULL, div->width, 0);
-}
-EXPORT_SYMBOL_GPL(sprd_div_helper_round_rate);
-
 static long sprd_div_round_rate(struct clk_hw *hw, unsigned long rate,
 				unsigned long *parent_rate)
 {
 	struct sprd_div *cd = hw_to_sprd_div(hw);
 
-	return sprd_div_helper_round_rate(&cd->common, &cd->div,
-					  rate, parent_rate);
+	return divider_round_rate(&cd->common.hw, rate, parent_rate, NULL,
+				  cd->div.width, 0);
 }
 
 unsigned long sprd_div_helper_recalc_rate(struct sprd_clk_common *common,

drivers/clk/sprd/div.h

@@ -64,11 +64,6 @@ static inline struct sprd_div *hw_to_sprd_div(const struct clk_hw *hw)
 	return container_of(common, struct sprd_div, common);
 }
 
-long sprd_div_helper_round_rate(struct sprd_clk_common *common,
-				const struct sprd_div_internal *div,
-				unsigned long rate,
-				unsigned long *parent_rate);
-
 unsigned long sprd_div_helper_recalc_rate(struct sprd_clk_common *common,
 					  const struct sprd_div_internal *div,
 					  unsigned long parent_rate);