This is a note to let you know that I've just added the patch titled
clk: tegra: Add missing reset deassertion
to the 5.17-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
clk-tegra-add-missing-reset-deassertion.patch
and it can be found in the queue-5.17 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 23a43cc437e747473d5f8f98b4fe189fb5c433b7 Mon Sep 17 00:00:00 2001
From: Diogo Ivo <diogo.ivo@xxxxxxxxxxxxxxxxxx>
Date: Fri, 29 Apr 2022 13:58:43 +0100
Subject: clk: tegra: Add missing reset deassertion
From: Diogo Ivo <diogo.ivo@xxxxxxxxxxxxxxxxxx>
commit 23a43cc437e747473d5f8f98b4fe189fb5c433b7 upstream.
Commit 4782c0a5dd88 ("clk: tegra: Don't deassert reset on enabling
clocks") removed deassertion of reset lines when enabling peripheral
clocks. This breaks the initialization of the DFLL driver which relied
on this behaviour.
Fix this problem by adding explicit deassert/assert requests to the
driver. Tested on Google Pixel C.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 4782c0a5dd88 ("clk: tegra: Don't deassert reset on enabling clocks")
Signed-off-by: Diogo Ivo <diogo.ivo@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/clk/tegra/clk-dfll.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
--- a/drivers/clk/tegra/clk-dfll.c
+++ b/drivers/clk/tegra/clk-dfll.c
@@ -271,6 +271,7 @@ struct tegra_dfll {
struct clk *ref_clk;
struct clk *i2c_clk;
struct clk *dfll_clk;
+ struct reset_control *dfll_rst;
struct reset_control *dvco_rst;
unsigned long ref_rate;
unsigned long i2c_clk_rate;
@@ -1464,6 +1465,7 @@ static int dfll_init(struct tegra_dfll *
return -EINVAL;
}
+ reset_control_deassert(td->dfll_rst);
reset_control_deassert(td->dvco_rst);
ret = clk_prepare(td->ref_clk);
@@ -1509,6 +1511,7 @@ di_err1:
clk_unprepare(td->ref_clk);
reset_control_assert(td->dvco_rst);
+ reset_control_assert(td->dfll_rst);
return ret;
}
@@ -1530,6 +1533,7 @@ int tegra_dfll_suspend(struct device *de
}
reset_control_assert(td->dvco_rst);
+ reset_control_assert(td->dfll_rst);
return 0;
}
@@ -1548,6 +1552,7 @@ int tegra_dfll_resume(struct device *dev
{
struct tegra_dfll *td = dev_get_drvdata(dev);
+ reset_control_deassert(td->dfll_rst);
reset_control_deassert(td->dvco_rst);
pm_runtime_get_sync(td->dev);
@@ -1951,6 +1956,12 @@ int tegra_dfll_register(struct platform_
td->soc = soc;
+ td->dfll_rst = devm_reset_control_get_optional(td->dev, "dfll");
+ if (IS_ERR(td->dfll_rst)) {
+ dev_err(td->dev, "couldn't get dfll reset\n");
+ return PTR_ERR(td->dfll_rst);
+ }
+
td->dvco_rst = devm_reset_control_get(td->dev, "dvco");
if (IS_ERR(td->dvco_rst)) {
dev_err(td->dev, "couldn't get dvco reset\n");
@@ -2087,6 +2098,7 @@ struct tegra_dfll_soc_data *tegra_dfll_u
clk_unprepare(td->i2c_clk);
reset_control_assert(td->dvco_rst);
+ reset_control_assert(td->dfll_rst);
return td->soc;
}
Patches currently in stable-queue which might be from diogo.ivo@xxxxxxxxxxxxxxxxxx are
queue-5.17/clk-tegra-add-missing-reset-deassertion.patch
queue-5.17/arm64-tegra-add-missing-dfll-reset-on-tegra210.patch
