[PATCH v2 2/3] clk: renesas: Use bitfield helpers

[Geert Uytterhoeven <geert+renesas@xxxxxxxxx>]

Use the FIELD_{GET,PREP}() and field_{get,prep}() helpers for const
respective non-const bitfields, instead of open-coding the same
operations.

Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
v2:
  - Rebase on top of commit 470e3f0d0b1529ab ("clk: renesas: rcar-gen4:
    Introduce R-Car Gen4 CPG driver").
---
 drivers/clk/renesas/clk-div6.c      |  6 +++---
 drivers/clk/renesas/rcar-gen3-cpg.c | 15 +++++----------
 drivers/clk/renesas/rcar-gen4-cpg.c |  9 +++------
 3 files changed, 11 insertions(+), 19 deletions(-)

diff --git a/drivers/clk/renesas/clk-div6.c b/drivers/clk/renesas/clk-div6.c
index 3abd6e5400aded6a..f7b827b5e9b2dd32 100644
--- a/drivers/clk/renesas/clk-div6.c
+++ b/drivers/clk/renesas/clk-div6.c
@@ -7,6 +7,7 @@
  * Contact: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
  */
 
+#include <linux/bitfield.h>
 #include <linux/clk-provider.h>
 #include <linux/init.h>
 #include <linux/io.h>
@@ -171,8 +172,7 @@ static u8 cpg_div6_clock_get_parent(struct clk_hw *hw)
 	if (clock->src_mask == 0)
 		return 0;
 
-	hw_index = (readl(clock->reg) & clock->src_mask) >>
-		   __ffs(clock->src_mask);
+	hw_index = field_get(clock->src_mask, readl(clock->reg));
 	for (i = 0; i < clk_hw_get_num_parents(hw); i++) {
 		if (clock->parents[i] == hw_index)
 			return i;
@@ -191,7 +191,7 @@ static int cpg_div6_clock_set_parent(struct clk_hw *hw, u8 index)
 	if (index >= clk_hw_get_num_parents(hw))
 		return -EINVAL;
 
-	src = clock->parents[index] << __ffs(clock->src_mask);
+	src = field_prep(clock->src_mask, clock->parents[index]);
 	writel((readl(clock->reg) & ~clock->src_mask) | src, clock->reg);
 	return 0;
 }
diff --git a/drivers/clk/renesas/rcar-gen3-cpg.c b/drivers/clk/renesas/rcar-gen3-cpg.c
index 027100e84ee4c429..ca8f6a68771628fb 100644
--- a/drivers/clk/renesas/rcar-gen3-cpg.c
+++ b/drivers/clk/renesas/rcar-gen3-cpg.c
@@ -54,10 +54,8 @@ static unsigned long cpg_pll_clk_recalc_rate(struct clk_hw *hw,
 {
 	struct cpg_pll_clk *pll_clk = to_pll_clk(hw);
 	unsigned int mult;
-	u32 val;
 
-	val = readl(pll_clk->pllcr_reg) & CPG_PLLnCR_STC_MASK;
-	mult = (val >> __ffs(CPG_PLLnCR_STC_MASK)) + 1;
+	mult = FIELD_GET(CPG_PLLnCR_STC_MASK, readl(pll_clk->pllcr_reg)) + 1;
 
 	return parent_rate * mult * pll_clk->fixed_mult;
 }
@@ -94,7 +92,7 @@ static int cpg_pll_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 
 	val = readl(pll_clk->pllcr_reg);
 	val &= ~CPG_PLLnCR_STC_MASK;
-	val |= (mult - 1) << __ffs(CPG_PLLnCR_STC_MASK);
+	val |= FIELD_PREP(CPG_PLLnCR_STC_MASK, mult - 1);
 	writel(val, pll_clk->pllcr_reg);
 
 	for (i = 1000; i; i--) {
@@ -176,11 +174,7 @@ static unsigned long cpg_z_clk_recalc_rate(struct clk_hw *hw,
 					   unsigned long parent_rate)
 {
 	struct cpg_z_clk *zclk = to_z_clk(hw);
-	unsigned int mult;
-	u32 val;
-
-	val = readl(zclk->reg) & zclk->mask;
-	mult = 32 - (val >> __ffs(zclk->mask));
+	unsigned int mult = 32 - field_get(zclk->mask, readl(zclk->reg));
 
 	return DIV_ROUND_CLOSEST_ULL((u64)parent_rate * mult,
 				     32 * zclk->fixed_div);
@@ -231,7 +225,8 @@ static int cpg_z_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 	if (readl(zclk->kick_reg) & CPG_FRQCRB_KICK)
 		return -EBUSY;
 
-	cpg_reg_modify(zclk->reg, zclk->mask, (32 - mult) << __ffs(zclk->mask));
+	cpg_reg_modify(zclk->reg, zclk->mask,
+		       field_prep(zclk->mask, 32 - mult));
 
 	/*
 	 * Set KICK bit in FRQCRB to update hardware setting and wait for
diff --git a/drivers/clk/renesas/rcar-gen4-cpg.c b/drivers/clk/renesas/rcar-gen4-cpg.c
index 31aa790fd003d45e..a63114a1d431968f 100644
--- a/drivers/clk/renesas/rcar-gen4-cpg.c
+++ b/drivers/clk/renesas/rcar-gen4-cpg.c
@@ -279,11 +279,7 @@ static unsigned long cpg_z_clk_recalc_rate(struct clk_hw *hw,
 					   unsigned long parent_rate)
 {
 	struct cpg_z_clk *zclk = to_z_clk(hw);
-	unsigned int mult;
-	u32 val;
-
-	val = readl(zclk->reg) & zclk->mask;
-	mult = 32 - (val >> __ffs(zclk->mask));
+	unsigned int mult = 32 - field_get(zclk->mask, readl(zclk->reg));
 
 	return DIV_ROUND_CLOSEST_ULL((u64)parent_rate * mult,
 				     32 * zclk->fixed_div);
@@ -334,7 +330,8 @@ static int cpg_z_clk_set_rate(struct clk_hw *hw, unsigned long rate,
 	if (readl(zclk->kick_reg) & CPG_FRQCRB_KICK)
 		return -EBUSY;
 
-	cpg_reg_modify(zclk->reg, zclk->mask, (32 - mult) << __ffs(zclk->mask));
+	cpg_reg_modify(zclk->reg, zclk->mask,
+		       field_prep(zclk->mask, 32 - mult));
 
 	/*
 	 * Set KICK bit in FRQCRB to update hardware setting and wait for
-- 
2.43.0