[PATCH v2 04/12] clk: qcom: clk-regmap-divider: Support CLK_DIVIDER_* flags

[Luo Jie]

Add a flags field to struct clk_regmap_div and OR it into the
CLK_DIVIDER_ROUND_CLOSEST flag passed to divider_determine_rate(),
divider_ro_determine_rate(), divider_get_val(), and
divider_recalc_rate(), so that qcom drivers can opt into
CLK_DIVIDER_* behavior variants such as
CLK_DIVIDER_EVEN_INTEGERS_NO_OFFSET.

This is additive and backward compatible: existing clk_regmap_div
users don't initialize .flags, so it defaults to 0, and
CLK_DIVIDER_ROUND_CLOSEST | 0 is identical to current behavior.

divider_get_val() can now return -EINVAL once a caller sets a
divisor-constraining flag such as CLK_DIVIDER_EVEN_INTEGERS_NO_OFFSET
(previously unreachable, since no flag passed here constrained
_is_valid_div()). Check for this in div_set_rate() before using the
result, mirroring clk_divider_set_rate()'s existing handling of the
same return value.

Signed-off-by: Luo Jie <jie.luo@xxxxxxxxxxxxxxxx>
---
 drivers/clk/qcom/clk-regmap-divider.c | 14 +++++++++-----
 drivers/clk/qcom/clk-regmap-divider.h |  1 +
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/clk/qcom/clk-regmap-divider.c b/drivers/clk/qcom/clk-regmap-divider.c
index 672e82caf205..fe4542b5bd58 100644
--- a/drivers/clk/qcom/clk-regmap-divider.c
+++ b/drivers/clk/qcom/clk-regmap-divider.c
@@ -27,7 +27,8 @@ static int div_ro_determine_rate(struct clk_hw *hw,
 	val &= BIT(divider->width) - 1;
 
 	return divider_ro_determine_rate(hw, req, NULL, divider->width,
-					 CLK_DIVIDER_ROUND_CLOSEST, val);
+					 CLK_DIVIDER_ROUND_CLOSEST | divider->flags,
+					 val);
 }
 
 static int div_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
@@ -35,7 +36,7 @@ static int div_determine_rate(struct clk_hw *hw, struct clk_rate_request *req)
 	struct clk_regmap_div *divider = to_clk_regmap_div(hw);
 
 	return divider_determine_rate(hw, req, NULL, divider->width,
-				      CLK_DIVIDER_ROUND_CLOSEST);
+				      CLK_DIVIDER_ROUND_CLOSEST | divider->flags);
 }
 
 static int div_set_rate(struct clk_hw *hw, unsigned long rate,
@@ -43,10 +44,12 @@ static int div_set_rate(struct clk_hw *hw, unsigned long rate,
 {
 	struct clk_regmap_div *divider = to_clk_regmap_div(hw);
 	struct clk_regmap *clkr = &divider->clkr;
-	u32 div;
+	int div;
 
 	div = divider_get_val(rate, parent_rate, NULL, divider->width,
-			      CLK_DIVIDER_ROUND_CLOSEST);
+			      CLK_DIVIDER_ROUND_CLOSEST | divider->flags);
+	if (div < 0)
+		return div;
 
 	return regmap_update_bits(clkr->regmap, divider->reg,
 				  (BIT(divider->width) - 1) << divider->shift,
@@ -65,7 +68,8 @@ static unsigned long div_recalc_rate(struct clk_hw *hw,
 	div &= BIT(divider->width) - 1;
 
 	return divider_recalc_rate(hw, parent_rate, div, NULL,
-				   CLK_DIVIDER_ROUND_CLOSEST, divider->width);
+				   CLK_DIVIDER_ROUND_CLOSEST | divider->flags,
+				   divider->width);
 }
 
 const struct clk_ops clk_regmap_div_ops = {
diff --git a/drivers/clk/qcom/clk-regmap-divider.h b/drivers/clk/qcom/clk-regmap-divider.h
index e75a65c3839c..4fde766b2633 100644
--- a/drivers/clk/qcom/clk-regmap-divider.h
+++ b/drivers/clk/qcom/clk-regmap-divider.h
@@ -13,6 +13,7 @@ struct clk_regmap_div {
 	u32			reg;
 	u32			shift;
 	u32			width;
+	unsigned long		flags;
 	struct clk_regmap	clkr;
 };
 

-- 
2.43.0