[PATCH 4.19 25/25] clk: iproc: Do not rely on node name for correct PLL setup

From: Greg Kroah-Hartman
Date: Mon Oct 03 2022 - 03:45:07 EST

From: Florian Fainelli <f.fainelli@xxxxxxxxx>

[ Upstream commit 1b24a132eba7a1c19475ba2510ec1c00af3ff914 ]

After commit 31fd9b79dc58 ("ARM: dts: BCM5301X: update CRU block
description") a warning from clk-iproc-pll.c was generated due to a
duplicate PLL name as well as the console stopped working. Upon closer
inspection it became clear that iproc_pll_clk_setup() used the Device
Tree node unit name as an unique identifier as well as a parent name to
parent all clocks under the PLL.

BCM5301X was the first platform on which that got noticed because of the
DT node unit name renaming but the same assumptions hold true for any
user of the iproc_pll_clk_setup() function.

The first 'clock-output-names' property is always guaranteed to be
unique as well as providing the actual desired PLL clock name, so we
utilize that to register the PLL and as a parent name of all children

Fixes: 5fe225c105fd ("clk: iproc: add initial common clock support")
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Acked-by: Rafał Miłecki <rafal@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20220905161504.1526-1-f.fainelli@xxxxxxxxx
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
drivers/clk/bcm/clk-iproc-pll.c | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/clk/bcm/clk-iproc-pll.c b/drivers/clk/bcm/clk-iproc-pll.c
index 274441e2ddb2..8f0619f362e3 100644
--- a/drivers/clk/bcm/clk-iproc-pll.c
+++ b/drivers/clk/bcm/clk-iproc-pll.c
@@ -736,6 +736,7 @@ void iproc_pll_clk_setup(struct device_node *node,
const char *parent_name;
struct iproc_clk *iclk_array;
struct clk_hw_onecell_data *clk_data;
+ const char *clk_name;

if (WARN_ON(!pll_ctrl) || WARN_ON(!clk_ctrl))
@@ -783,7 +784,12 @@ void iproc_pll_clk_setup(struct device_node *node,
iclk = &iclk_array[0];
iclk->pll = pll;

- init.name = node->name;
+ ret = of_property_read_string_index(node, "clock-output-names",
+ 0, &clk_name);
+ if (WARN_ON(ret))
+ goto err_pll_register;
+ init.name = clk_name;
init.ops = &iproc_pll_ops;
init.flags = 0;
parent_name = of_clk_get_parent_name(node, 0);
@@ -803,13 +809,11 @@ void iproc_pll_clk_setup(struct device_node *node,
goto err_pll_register;

clk_data->hws[0] = &iclk->hw;
+ parent_name = clk_name;

/* now initialize and register all leaf clocks */
for (i = 1; i < num_clks; i++) {
- const char *clk_name;
memset(&init, 0, sizeof(init));
- parent_name = node->name;

ret = of_property_read_string_index(node, "clock-output-names",
i, &clk_name);