Currently the driver uses of_clk_hw_onecell_get() for all clocks it
manages, but this is incorrect for the audio refclk, which has 0 rather
than 1 clock cell according to its binding documentation [1]; attempting
to look up the clock when referenced like this in the Device Tree leads
to errors, as uninitialized memory is passed to of_clk_hw_onecell_get()
as the index.
The actual fix is in patch 3; patches 1 and 2 are preparation and
related cleanup. I've added a Fixes: tag to all 3 patches, as they
need to be backported together.
Matthias Schiffer (3):
clk: keystone: syscon-clk: use struct instead of array for match data
clk: keystone: syscon-clk: specify whether a parent is required in
match data
clk: keystone: syscon-clk: use of_clk_hw_simple_get() for audio refclk
[1] https://www.kernel.org/doc/Documentation/devicetree/bindings/clock/ti,am62-audio-refclk.yaml
drivers/clk/keystone/syscon-clk.c | 73 ++++++++++++++++++++-----------
1 file changed, 48 insertions(+), 25 deletions(-)
--
TQ-Systems GmbH | Mühlstraße 2, Gut Delling | 82229 Seefeld, Germany
Amtsgericht München, HRB 105018
Geschäftsführer: Detlef Schneider, Rüdiger Stahl, Stefan Schneider
https://www.tq-group.com/
The binding documentation for ti,am62-audio-refclk specifies that it has 0
clock cells (and Device Trees using the binding as documented have already
existed in vendor kernels for some time). Fix the driver to use
of_clk_hw_simple_get() instead of of_clk_hw_onecell_get(), as attempting
to reference the clock in the Device Tree will fail otherwise.
Fixes: 6acab96ee337 ("clk: keystone: syscon-clk: Add support for audio refclk")
Signed-off-by: Matthias Schiffer <[email protected]>
---
drivers/clk/keystone/syscon-clk.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/clk/keystone/syscon-clk.c b/drivers/clk/keystone/syscon-clk.c
index 9626a877e072..a539dbf2f48e 100644
--- a/drivers/clk/keystone/syscon-clk.c
+++ b/drivers/clk/keystone/syscon-clk.c
@@ -28,6 +28,7 @@ struct ti_syscon_gate_clk_data {
const struct ti_syscon_gate_clk_entry *clks;
size_t num_clks;
bool needs_parent;
+ bool simple; /* Use of_clk_hw_simple_get() rather than onecell */
};
static struct
@@ -129,6 +130,10 @@ static int ti_syscon_gate_clk_probe(struct platform_device *pdev)
return dev_err_probe(dev, PTR_ERR(regmap),
"failed to get regmap\n");
+ if (data->simple && data->num_clks != 1)
+ return dev_err_probe(dev, -EINVAL,
+ "simple clocks must have exactly 1 entry\n");
+
num_parents = of_clk_get_parent_count(dev->of_node);
if (data->needs_parent && num_parents == 0)
return dev_err_probe(dev, -EINVAL,
@@ -151,8 +156,12 @@ static int ti_syscon_gate_clk_probe(struct platform_device *pdev)
data->clks[i].name);
}
- return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
- hw_data);
+ if (data->simple)
+ return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
+ hw_data->hws[0]);
+ else
+ return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get,
+ hw_data);
}
#define TI_SYSCON_CLK_GATE(_name, _offset, _bit_idx) \
@@ -208,6 +217,7 @@ static const struct ti_syscon_gate_clk_data am62_audio_clk_data = {
.clks = am62_audio_clks,
.num_clks = ARRAY_SIZE(am62_audio_clks),
.needs_parent = true,
+ .simple = true,
};
static const struct of_device_id ti_syscon_gate_clk_ids[] = {
--
TQ-Systems GmbH | Mühlstraße 2, Gut Delling | 82229 Seefeld, Germany
Amtsgericht München, HRB 105018
Geschäftsführer: Detlef Schneider, Rüdiger Stahl, Stefan Schneider
https://www.tq-group.com/
Avoid checking the compatible string again in the probe function.
No functional change intended.
Fixes: 6acab96ee337 ("clk: keystone: syscon-clk: Add support for audio refclk")
Signed-off-by: Matthias Schiffer <[email protected]>
---
drivers/clk/keystone/syscon-clk.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/clk/keystone/syscon-clk.c b/drivers/clk/keystone/syscon-clk.c
index 68ac536f564e..9626a877e072 100644
--- a/drivers/clk/keystone/syscon-clk.c
+++ b/drivers/clk/keystone/syscon-clk.c
@@ -27,6 +27,7 @@ struct ti_syscon_gate_clk_entry {
struct ti_syscon_gate_clk_data {
const struct ti_syscon_gate_clk_entry *clks;
size_t num_clks;
+ bool needs_parent;
};
static struct
@@ -129,11 +130,9 @@ static int ti_syscon_gate_clk_probe(struct platform_device *pdev)
"failed to get regmap\n");
num_parents = of_clk_get_parent_count(dev->of_node);
- if (of_device_is_compatible(dev->of_node, "ti,am62-audio-refclk") &&
- num_parents == 0) {
+ if (data->needs_parent && num_parents == 0)
return dev_err_probe(dev, -EINVAL,
"must specify a parent clock\n");
- }
hw_data = devm_kzalloc(dev, struct_size(hw_data, hws, data->num_clks),
GFP_KERNEL);
@@ -208,6 +207,7 @@ static const struct ti_syscon_gate_clk_entry am62_audio_clks[] = {
static const struct ti_syscon_gate_clk_data am62_audio_clk_data = {
.clks = am62_audio_clks,
.num_clks = ARRAY_SIZE(am62_audio_clks),
+ .needs_parent = true,
};
static const struct of_device_id ti_syscon_gate_clk_ids[] = {
--
TQ-Systems GmbH | Mühlstraße 2, Gut Delling | 82229 Seefeld, Germany
Amtsgericht München, HRB 105018
Geschäftsführer: Detlef Schneider, Rüdiger Stahl, Stefan Schneider
https://www.tq-group.com/
On Tue, Aug 01, 2023 at 12:36:06PM +0200, Matthias Schiffer wrote:
> The actual fix is in patch 3; patches 1 and 2 are preparation and
> related cleanup. I've added a Fixes: tag to all 3 patches, as they
> need to be backported together.
Please see this https://lore.kernel.org/all/[email protected]/
that was sent a few days ago. It fixes the same issue and it's already
reviewed.
Francesco