[PATCH 7/9] drm/bridge: tc358767: Introduce tc_set_syspllparam()

[Andrey Smirnov <andrew.smirnov@gmail.com>]

Move common code converting clock rate to an appropriate constant and
configuring SYS_PLLPARAM register into a separate routine and convert
the rest of the code to use it. No functional change intended.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Archit Taneja <architt@codeaurora.org>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
---
 drivers/gpu/drm/bridge/tc358767.c | 50 +++++++++++++------------------
 1 file changed, 20 insertions(+), 30 deletions(-)

diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c
index 54ff95f66e30..227f14cd2d3d 100644
--- a/drivers/gpu/drm/bridge/tc358767.c
+++ b/drivers/gpu/drm/bridge/tc358767.c
@@ -522,35 +522,42 @@ static int tc_stream_clock_calc(struct tc_data *tc)
 	return regmap_write(tc->regmap, DP0_VIDMNGEN1, 32768);
 }
 
-static int tc_aux_link_setup(struct tc_data *tc)
+static int tc_set_syspllparam(struct tc_data *tc)
 {
 	unsigned long rate;
-	u32 value;
-	int ret;
-	u32 dp_phy_ctrl;
+	u32 pllparam = SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
 
 	rate = clk_get_rate(tc->refclk);
 	switch (rate) {
 	case 38400000:
-		value = REF_FREQ_38M4;
+		pllparam |= REF_FREQ_38M4;
 		break;
 	case 26000000:
-		value = REF_FREQ_26M;
+		pllparam |= REF_FREQ_26M;
 		break;
 	case 19200000:
-		value = REF_FREQ_19M2;
+		pllparam |= REF_FREQ_19M2;
 		break;
 	case 13000000:
-		value = REF_FREQ_13M;
+		pllparam |= REF_FREQ_13M;
 		break;
 	default:
 		dev_err(tc->dev, "Invalid refclk rate: %lu Hz\n", rate);
 		return -EINVAL;
 	}
 
+	return regmap_write(tc->regmap, SYS_PLLPARAM, pllparam);
+}
+
+static int tc_aux_link_setup(struct tc_data *tc)
+{
+	int ret;
+	u32 dp_phy_ctrl;
+
 	/* Setup DP-PHY / PLL */
-	value |= SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
-	tc_write(SYS_PLLPARAM, value);
+	ret = tc_set_syspllparam(tc);
+	if (ret)
+		return ret;
 
 	dp_phy_ctrl = BGREN | PWR_SW_EN | PHY_A0_EN;
 	if (tc->link.base.num_lanes == 2)
@@ -811,7 +818,6 @@ static int tc_main_link_setup(struct tc_data *tc)
 {
 	struct drm_dp_aux *aux = &tc->aux;
 	struct device *dev = tc->dev;
-	unsigned int rate;
 	u32 dp_phy_ctrl;
 	int timeout;
 	u32 value;
@@ -828,25 +834,9 @@ static int tc_main_link_setup(struct tc_data *tc)
 		 (tc->link.spread ? DP0_SRCCTRL_SSCG : 0) |
 		 ((tc->link.base.rate != 162000) ? DP0_SRCCTRL_BW27 : 0));
 
-	rate = clk_get_rate(tc->refclk);
-	switch (rate) {
-	case 38400000:
-		value = REF_FREQ_38M4;
-		break;
-	case 26000000:
-		value = REF_FREQ_26M;
-		break;
-	case 19200000:
-		value = REF_FREQ_19M2;
-		break;
-	case 13000000:
-		value = REF_FREQ_13M;
-		break;
-	default:
-		return -EINVAL;
-	}
-	value |= SYSCLK_SEL_LSCLK | LSCLK_DIV_2;
-	tc_write(SYS_PLLPARAM, value);
+	ret = tc_set_syspllparam(tc);
+	if (ret)
+		return ret;
 
 	/* Setup Main Link */
 	dp_phy_ctrl = BGREN | PWR_SW_EN | PHY_A0_EN | PHY_M0_EN;
-- 
2.20.1