mirror of
https://github.com/openwrt/openwrt.git
synced 2024-12-29 18:19:02 +00:00
d2a2eb7e48
This driver has been cherry-picked and backported from the following LKML thread: *https://lkml.org/lkml/2015/5/26/744 It also updates the DT accordingly. Signed-off-by: Mathieu Olivari <mathieu@codeaurora.org> SVN-Revision: 45831
56 lines
1.6 KiB
Diff
56 lines
1.6 KiB
Diff
From 6793b3cd5da817c4be218bd8632f07cf4d2b0d26 Mon Sep 17 00:00:00 2001
|
|
From: Hans de Goede <hdegoede@redhat.com>
|
|
Date: Wed, 19 Nov 2014 14:48:59 +0100
|
|
Subject: [PATCH] clk_mux: Fix set_parent doing the wrong thing when INDEX_BIT
|
|
&& index >= 3
|
|
|
|
If CLK_MUX_INDEX_BIT is set, then each bit turns on / off a single parent,
|
|
so theoretically multiple parents could be enabled at the same time, but in
|
|
practice only one bit should ever be 1. So to select parent 0, set
|
|
the register (*) to 0x01, to select parent 1 set it 0x02, parent 2, 0x04,
|
|
parent 3, 0x08, etc.
|
|
|
|
But the current code does:
|
|
|
|
if (mux->flags & CLK_MUX_INDEX_BIT)
|
|
index = (1 << ffs(index));
|
|
|
|
Which means that:
|
|
|
|
For an input index of 0, ffs returns 0, so we set the register
|
|
to 0x01, ok.
|
|
|
|
For an input index of 1, ffs returns 1, so we set the register
|
|
to 0x02, ok.
|
|
|
|
For an input index of 2, ffs returns 2, so we set the register
|
|
to 0x04, ok.
|
|
|
|
For an input index of 3, ffs returns 1, so we set the register
|
|
to 0x02, not good!
|
|
|
|
The code should simply be:
|
|
|
|
if (mux->flags & CLK_MUX_INDEX_BIT)
|
|
index = 1 << index;
|
|
|
|
Which always does the right thing, this commit fixes this.
|
|
|
|
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
|
|
Signed-off-by: Michael Turquette <mturquette@linaro.org>
|
|
---
|
|
drivers/clk/clk-mux.c | 2 +-
|
|
1 file changed, 1 insertion(+), 1 deletion(-)
|
|
|
|
--- a/drivers/clk/clk-mux.c
|
|
+++ b/drivers/clk/clk-mux.c
|
|
@@ -77,7 +77,7 @@ static int clk_mux_set_parent(struct clk
|
|
|
|
else {
|
|
if (mux->flags & CLK_MUX_INDEX_BIT)
|
|
- index = (1 << ffs(index));
|
|
+ index = 1 << index;
|
|
|
|
if (mux->flags & CLK_MUX_INDEX_ONE)
|
|
index++;
|