clk: mediatek: Disable tuner_en before change PLL rate

commit be17ca6a upstream.

PLLs with tuner_en bit, such as APLL1, need to disable
tuner_en before apply new frequency settings, or the new frequency
settings (pcw) will not be applied.
The tuner_en bit will be disabled during changing PLL rate
and be restored after new settings applied.

Fixes: e2f744a8 (clk: mediatek: Add MT2712 clock support)
Cc: <stable@vger.kernel.org>
Signed-off-by: Owen Chen <owen.chen@mediatek.com>
Signed-off-by: Weiyi Lu <weiyi.lu@mediatek.com>
Reviewed-by: James Liao <jamesjj.liao@mediatek.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/clk/mediatek/clk-pll.c

@@ -88,6 +88,32 @@ static unsigned long __mtk_pll_recalc_rate(struct mtk_clk_pll *pll, u32 fin,
 	return ((unsigned long)vco + postdiv - 1) / postdiv;
 }
 
+static void __mtk_pll_tuner_enable(struct mtk_clk_pll *pll)
+{
+	u32 r;
+
+	if (pll->tuner_en_addr) {
+		r = readl(pll->tuner_en_addr) | BIT(pll->data->tuner_en_bit);
+		writel(r, pll->tuner_en_addr);
+	} else if (pll->tuner_addr) {
+		r = readl(pll->tuner_addr) | AUDPLL_TUNER_EN;
+		writel(r, pll->tuner_addr);
+	}
+}
+
+static void __mtk_pll_tuner_disable(struct mtk_clk_pll *pll)
+{
+	u32 r;
+
+	if (pll->tuner_en_addr) {
+		r = readl(pll->tuner_en_addr) & ~BIT(pll->data->tuner_en_bit);
+		writel(r, pll->tuner_en_addr);
+	} else if (pll->tuner_addr) {
+		r = readl(pll->tuner_addr) & ~AUDPLL_TUNER_EN;
+		writel(r, pll->tuner_addr);
+	}
+}
+
 static void mtk_pll_set_rate_regs(struct mtk_clk_pll *pll, u32 pcw,
 		int postdiv)
 {
@@ -96,6 +122,9 @@ static void mtk_pll_set_rate_regs(struct mtk_clk_pll *pll, u32 pcw,
 
 	pll_en = readl(pll->base_addr + REG_CON0) & CON0_BASE_EN;
 
+	/* disable tuner */
+	__mtk_pll_tuner_disable(pll);
+
 	/* set postdiv */
 	val = readl(pll->pd_addr);
 	val &= ~(POSTDIV_MASK << pll->data->pd_shift);
@@ -122,6 +151,9 @@ static void mtk_pll_set_rate_regs(struct mtk_clk_pll *pll, u32 pcw,
 	if (pll->tuner_addr)
 		writel(con1 + 1, pll->tuner_addr);
 
+	/* restore tuner_en */
+	__mtk_pll_tuner_enable(pll);
+
 	if (pll_en)
 		udelay(20);
 }
@@ -228,13 +260,7 @@ static int mtk_pll_prepare(struct clk_hw *hw)
 	r |= pll->data->en_mask;
 	writel(r, pll->base_addr + REG_CON0);
 
-	if (pll->tuner_en_addr) {
-		r = readl(pll->tuner_en_addr) | BIT(pll->data->tuner_en_bit);
-		writel(r, pll->tuner_en_addr);
-	} else if (pll->tuner_addr) {
-		r = readl(pll->tuner_addr) | AUDPLL_TUNER_EN;
-		writel(r, pll->tuner_addr);
-	}
+	__mtk_pll_tuner_enable(pll);
 
 	udelay(20);
 
@@ -258,13 +284,7 @@ static void mtk_pll_unprepare(struct clk_hw *hw)
 		writel(r, pll->base_addr + REG_CON0);
 	}
 
-	if (pll->tuner_en_addr) {
-		r = readl(pll->tuner_en_addr) & ~BIT(pll->data->tuner_en_bit);
-		writel(r, pll->tuner_en_addr);
-	} else if (pll->tuner_addr) {
-		r = readl(pll->tuner_addr) & ~AUDPLL_TUNER_EN;
-		writel(r, pll->tuner_addr);
-	}
+	__mtk_pll_tuner_disable(pll);
 
 	r = readl(pll->base_addr + REG_CON0);
 	r &= ~CON0_BASE_EN;