[PATCH 4.14 104/159] clk: sunxi-ng: sun5i: Fix bit offset of audio PLL post-divider

Greg Kroah-Hartman
2017-12-22T09:31:01Z

From: Chen-Yu Tsai <wens@csie.org>

[ Upstream commit d51fe3ba9773c8b6fc79f82bbe75d64baf604292 ]

The post-divider for the audio PLL is in bits [29:26], as specified
in the user manual, not [19:16] as currently programmed in the code.
The post-divider has a default register value of 2, i.e. a divider
of 3. This means the clock rate fed to the audio codec would be off.

This was discovered when porting sigma-delta modulation for the PLL
to sun5i, which needs the post-divider to be 1.

Fix the bit offset, so we do actually force the post-divider to a
certain value.

Fixes: 5e73761786d6 ("clk: sunxi-ng: Add sun5i CCU driver")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/clk/sunxi-ng/ccu-sun5i.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/clk/sunxi-ng/ccu-sun5i.c
+++ b/drivers/clk/sunxi-ng/ccu-sun5i.c
@@ -982,8 +982,8 @@ static void __init sun5i_ccu_init(struct

/* Force the PLL-Audio-1x divider to 4 */
val = readl(reg + SUN5I_PLL_AUDIO_REG);
- val &= ~GENMASK(19, 16);
- writel(val | (3 << 16), reg + SUN5I_PLL_AUDIO_REG);
+ val &= ~GENMASK(29, 26);
+ writel(val | (3 << 26), reg + SUN5I_PLL_AUDIO_REG);

/*
* Use the peripheral PLL as the AHB parent, instead of CPU /