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clk: raspberrypi: Handle cpufreq device registration failure

PATCH Applied Triet Hoang 4 participants 5 messages Sep 18

Subsystems (2)
Common clk Broadcom BCM2711/BCM2835 Arm architecture
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Triet Hoang

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#0 lore raw

PATCH 1/1 clk: raspberrypi: Handle cpufreq device registration failure

Check the return value of platform_device_register_data() when registering the raspberrypi-cpufreq device and propagate the error if registration fails.

This prevents the clock driver from reporting a successful probe when the cpufreq device could not be registered.

Signed-off-by Triet Hoang <[email protected]>
---
 drivers/clk/bcm/clk-raspberrypi.c | 2 ++
 1 file changed, 2 insertions(+)
drivers/clk/bcm/clk-raspberrypi.c +2 -0
index f1a99de6de4f..9882f243d681 100644
@@ -553,6 +553,8 @@ static int raspberrypi_clk_probe(struct platform_device *pdev)
 
 	rpi->cpufreq = platform_device_register_data(dev, "raspberrypi-cpufreq",
 						     -1, NULL, 0);
+	if (IS_ERR(rpi->cpufreq))
+		return PTR_ERR(rpi->cpufreq);
 
 	return 0;
 }
Signature · 1 line
2.53.0
AI review
#1 lore raw
Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: - [Medium] clk: raspberrypi: core clock probe fails if optional cpufreq device fails --

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] clk: raspberrypi: core clock probe fails if optional cpufreq device fails --

commit 9a3a7cc11a038dd3ae191483f044c2febc6c2ed1
Author: Triet Hoang <[email protected]>
clk: raspberrypi: Handle cpufreq device registration failure

This commit adds an error check when registering the raspberrypi-cpufreq device in the clock driver probe function. It propagates the error if the cpufreq device fails to register, preventing a successful probe return.

drivers/clk/bcm/clk-raspberrypi.c static int raspberrypi_clk_probe(struct platform_device *pdev) · line 557

Quoted 10 lines
drivers/clk/bcm/clk-raspberrypi.c +2 -0
index f1a99de6de4f1..9882f243d6813 100644
@@ -553,6 +553,8 @@ static int raspberrypi_clk_probe(struct platform_device *pdev)
 
 	rpi->cpufreq = platform_device_register_data(dev, "raspberrypi-cpufreq",
 						     -1, NULL, 0);
+	if (IS_ERR(rpi->cpufreq))
+		return PTR_ERR(rpi->cpufreq);

[Severity: Medium]
Does this introduce a regression where fundamental core clocks might be unregistered if the optional cpufreq device fails?

The raspberrypi-clk driver provides essential system clocks, such as arm, core, and pixel. By returning an error from raspberrypi_clk_probe(), devres will automatically unregister these clocks. This can prevent other fundamental SoC devices that depend on these clocks from probing, which could severely degrade the system or prevent it from booting entirely.

Is it safe to structurally tie the survival of the core clocks to an optional dynamic frequency scaling child device?

Quoted 3 lines
drivers/clk/bcm/clk-raspberrypi.c +0 -0
 	return 0;
 }
Signature · 1 line
Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=1
Reviewed-by on v1 1/1
#2 lore raw
In reply to Triet Hoang

Hi Triet,

nice catch.

Am 18.09.26 um 06:41 schrieb Triet Hoang:

Quoted 8 lines

Check the return value of platform_device_register_data() when registering the raspberrypi-cpufreq device and propagate the error if registration fails.

This prevents the clock driver from reporting a successful probe when the cpufreq device could not be registered.

Signed-off-by Triet Hoang <[email protected]>
Reviewed-by Stefan Wahren <[email protected]>

Could you please add a Fixes tag?
Also it would be nice, if you can send a patch which also fixes drivers/firmware/raspberrypi.c

Thanks

Quoted 17 lines
---
  drivers/clk/bcm/clk-raspberrypi.c | 2 ++
  1 file changed, 2 insertions(+)
drivers/clk/bcm/clk-raspberrypi.c +2 -0
index f1a99de6de4f..9882f243d681 100644
@@ -553,6 +553,8 @@ static int raspberrypi_clk_probe(struct platform_device *pdev)
 
  	rpi->cpufreq = platform_device_register_data(dev, "raspberrypi-cpufreq",
  						     -1, NULL, 0);
+	if (IS_ERR(rpi->cpufreq))
+		return PTR_ERR(rpi->cpufreq);
 
  	return 0;
  }
#3 lore raw
In reply to Triet Hoang
Quoted 8 lines · Triet Hoang

Check the return value of platform_device_register_data() when registering the raspberrypi-cpufreq device and propagate the error if registration fails.

This prevents the clock driver from reporting a successful probe when the cpufreq device could not be registered.

Signed-off-by Triet Hoang <[email protected]>
Fixes e2bb18347c8e5 ("clk: raspberrypi: register platform device for raspberrypi-cpufreq")
Applied
#4 lore raw
In reply to Triet Hoang
Quoted 1 line · Triet Hoang

clk: raspberrypi: Handle cpufreq device registration failure

Applied, thanks!

[1/1] clk: raspberrypi: Handle cpufreq device registration failure

      commit: e98e3d712023859af7cd78bb7fdb87ea3a9ffb83

Best regards,

Signature · 1 line
Brian Masney <[email protected]>