[PATCH v4 16/21] thermal/drivers/intel/bxt_pmic: convert to use devm_request*_irq_probe()

From: Yangtao Li
Date: Mon Jul 10 2023 - 06:04:59 EST


There are more than 700 calls to devm_request_threaded_irq method and
more than 1000 calls to devm_request_irq method. Most drivers only
request one interrupt resource, and these error messages are basically
the same. If error messages are printed everywhere, more than 2000 lines
of code can be saved by removing the msg in the driver.

And tglx point out that:

If we actually look at the call sites of
devm_request_threaded_irq() then the vast majority of them print more or
less lousy error messages. A quick grep/sed/awk/sort/uniq revealed

519 messages total (there are probably more)

352 unique messages

323 unique messages after lower casing

Those 323 are mostly just variants of the same patterns with
slight modifications in formatting and information provided.

186 of these messages do not deliver any useful information,
e.g. "no irq", "

The most useful one of all is: "could request wakeup irq: %d"

So there is certainly an argument to be made that this particular
function should print a well formatted and informative error message.

It's not a general allocator like kmalloc(). It's specialized and in the
vast majority of cases failing to request the interrupt causes the
device probe to fail. So having proper and consistent information why
the device cannot be used _is_ useful.

So convert to use devm_request*_irq_probe() API, which ensure that all
error handling branches print error information.

In this way, when this function fails, the upper-layer functions can
directly return an error code without missing debugging information.
Otherwise, the error message will be printed redundantly or missing.

Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
Cc: "Uwe Kleine-König" <u.kleine-koenig@xxxxxxxxxxxxxx>
Cc: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
Signed-off-by: Yangtao Li <frank.li@xxxxxxxx>
---
drivers/thermal/intel/intel_bxt_pmic_thermal.c | 11 ++++-------
1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/drivers/thermal/intel/intel_bxt_pmic_thermal.c b/drivers/thermal/intel/intel_bxt_pmic_thermal.c
index 6312c6ba081f..1bf3e6bf8052 100644
--- a/drivers/thermal/intel/intel_bxt_pmic_thermal.c
+++ b/drivers/thermal/intel/intel_bxt_pmic_thermal.c
@@ -241,14 +241,11 @@ static int pmic_thermal_probe(struct platform_device *pdev)
return virq;
}

- ret = devm_request_threaded_irq(&pdev->dev, virq,
- NULL, pmic_thermal_irq_handler,
- IRQF_ONESHOT, "pmic_thermal", pdev);
-
- if (ret) {
- dev_err(dev, "request irq(%d) failed: %d\n", virq, ret);
+ ret = devm_request_threaded_irq_probe(&pdev->dev, virq, NULL,
+ pmic_thermal_irq_handler, IRQF_ONESHOT,
+ "pmic_thermal", pdev, NULL);
+ if (ret)
return ret;
- }
pmic_irq_count++;
}

--
2.39.0