[PATCH v3 08/10] phy: phy-snps-eusb2: refactor reference clock init

[Ivaylo Ivanov <ivo.ivanov.ivanov1@xxxxxxxxx>]

Instead of matching frequencies with a switch and case, introduce
a table-based lookup. This improves readability, reduces redundancy,
and makes it easier to extend support for additional frequencies in
the future.

Signed-off-by: Ivaylo Ivanov <ivo.ivanov.ivanov1@xxxxxxxxx>
---
 drivers/phy/phy-snps-eusb2.c | 61 +++++++++++++++++++-----------------
 1 file changed, 32 insertions(+), 29 deletions(-)

diff --git a/drivers/phy/phy-snps-eusb2.c b/drivers/phy/phy-snps-eusb2.c
index 1e7e75bbc..4ca11860a 100644
--- a/drivers/phy/phy-snps-eusb2.c
+++ b/drivers/phy/phy-snps-eusb2.c
@@ -192,44 +192,47 @@ static void qcom_eusb2_default_parameters(struct snps_eusb2_hsphy *phy)
 				    FIELD_PREP(PHY_CFG_TX_HS_XV_TUNE_MASK, 0x0));
 }
 
+struct snps_eusb2_ref_clk {
+	unsigned long freq;
+	u32 fsel_val;
+	u32 div_7_0_val;
+	u32 div_11_8_val;
+};
+
+static const struct snps_eusb2_ref_clk qcom_eusb2_ref_clk[] = {
+	{ 19200000, FSEL_19_2_MHZ_VAL, DIV_7_0_19_2_MHZ_VAL, DIV_11_8_19_2_MHZ_VAL },
+	{ 38400000, FSEL_38_4_MHZ_VAL, DIV_7_0_38_4_MHZ_VAL, DIV_11_8_38_4_MHZ_VAL },
+};
+
 static int qcom_eusb2_ref_clk_init(struct snps_eusb2_hsphy *phy)
 {
+	const struct snps_eusb2_ref_clk *config = NULL;
 	unsigned long ref_clk_freq = clk_get_rate(phy->ref_clk);
 
-	switch (ref_clk_freq) {
-	case 19200000:
-		snps_eusb2_hsphy_write_mask(phy->base, QCOM_USB_PHY_HS_PHY_CTRL_COMMON0,
-					    FSEL_MASK,
-					    FIELD_PREP(FSEL_MASK, FSEL_19_2_MHZ_VAL));
-
-		snps_eusb2_hsphy_write_mask(phy->base, QCOM_USB_PHY_CFG_CTRL_2,
-					    PHY_CFG_PLL_FB_DIV_7_0_MASK,
-					    DIV_7_0_19_2_MHZ_VAL);
-
-		snps_eusb2_hsphy_write_mask(phy->base, QCOM_USB_PHY_CFG_CTRL_3,
-					    PHY_CFG_PLL_FB_DIV_11_8_MASK,
-					    DIV_11_8_19_2_MHZ_VAL);
-		break;
-
-	case 38400000:
-		snps_eusb2_hsphy_write_mask(phy->base, QCOM_USB_PHY_HS_PHY_CTRL_COMMON0,
-					    FSEL_MASK,
-					    FIELD_PREP(FSEL_MASK, FSEL_38_4_MHZ_VAL));
-
-		snps_eusb2_hsphy_write_mask(phy->base, QCOM_USB_PHY_CFG_CTRL_2,
-					    PHY_CFG_PLL_FB_DIV_7_0_MASK,
-					    DIV_7_0_38_4_MHZ_VAL);
-
-		snps_eusb2_hsphy_write_mask(phy->base, QCOM_USB_PHY_CFG_CTRL_3,
-					    PHY_CFG_PLL_FB_DIV_11_8_MASK,
-					    DIV_11_8_38_4_MHZ_VAL);
-		break;
+	for (int i = 0; i < ARRAY_SIZE(qcom_eusb2_ref_clk); i++) {
+		if (qcom_eusb2_ref_clk[i].freq == ref_clk_freq) {
+			config = &qcom_eusb2_ref_clk[i];
+			break;
+		}
+	}
 
-	default:
+	if (!config) {
 		dev_err(&phy->phy->dev, "unsupported ref_clk_freq:%lu\n", ref_clk_freq);
 		return -EINVAL;
 	}
 
+	snps_eusb2_hsphy_write_mask(phy->base, QCOM_USB_PHY_HS_PHY_CTRL_COMMON0,
+				    FSEL_MASK,
+				    FIELD_PREP(FSEL_MASK, config->fsel_val));
+
+	snps_eusb2_hsphy_write_mask(phy->base, QCOM_USB_PHY_CFG_CTRL_2,
+				    PHY_CFG_PLL_FB_DIV_7_0_MASK,
+				    config->div_7_0_val);
+
+	snps_eusb2_hsphy_write_mask(phy->base, QCOM_USB_PHY_CFG_CTRL_3,
+				    PHY_CFG_PLL_FB_DIV_11_8_MASK,
+				    config->div_11_8_val);
+
 	snps_eusb2_hsphy_write_mask(phy->base, QCOM_USB_PHY_CFG_CTRL_3,
 				    PHY_CFG_PLL_REF_DIV, PLL_REF_DIV_VAL);
 
-- 
2.43.0