Moro Sakari,
Thanks for the review (and the suggestion)!
On 10/25/22 12:08, Sakari Ailus wrote:
Moi,
On Tue, Oct 25, 2022 at 11:50:59AM +0300, Matti Vaittinen wrote:
The fwnode_irq_get_byname() does return 0 upon device-tree IRQ mapping
failure. This is contradicting the function documentation and can
potentially be a source of errors like:
int probe(...) {
...
irq = fwnode_irq_get_byname();
if (irq <= 0)
return irq;
...
}
Here we do correctly check the return value from fwnode_irq_get_byname()
but the driver probe will now return success. (There was already one
such user in-tree).
Change the fwnode_irq_get_byname() to work as documented and according to
the common convention and abd always return a negative errno upon failure.
Fixes: ca0acb511c21 ("device property: Add fwnode_irq_get_byname")
Suggested-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
Signed-off-by: Matti Vaittinen <mazziesaccount@xxxxxxxxx>
---
I did a quick audit for the callers at v6.1-rc2:
drivers/i2c/i2c-smbus.c
drivers/iio/accel/adxl355_core.c
drivers/iio/gyro/fxas21002c_core.c
drivers/iio/imu/adis16480.c
drivers/iio/imu/bmi160/bmi160_core.c
drivers/iio/imu/bmi160/bmi160_core.c
I did not spot any errors to be caused by this change. There will be a
It won't as you're decreasing the possible values the function may
return...
Unless someone had implemented special handling for the IRQ mapping
failure...
functional change in i2c-smbus.c as the probe will now return -EINVAL
should the IRQ dt-mapping fail. It'd be nice if this was checked to be
Ok by the peeps knowing the i2c-smbus :)
FWIW, for both patches (but see below):
Reviewed-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
---
drivers/base/property.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/base/property.c b/drivers/base/property.c
index 4d6278a84868..bfc6c7286db2 100644
--- a/drivers/base/property.c
+++ b/drivers/base/property.c
@@ -964,7 +964,7 @@ EXPORT_SYMBOL(fwnode_irq_get);
*/
int fwnode_irq_get_byname(const struct fwnode_handle *fwnode, const char *name)
{
- int index;
+ int index, ret;
if (!name)
return -EINVAL;
@@ -973,7 +973,12 @@ int fwnode_irq_get_byname(const struct fwnode_handle *fwnode, const char *name)
if (index < 0)
return index;
- return fwnode_irq_get(fwnode, index);
+ ret = fwnode_irq_get(fwnode, index);
+
This newline is extra.
Or:
return ret ?: -EINVAL;
Or even:
return fwnode_irq_get(fwnode, index) ?: -EINVAL;
Up to you.
My personal preference is to not use the ternary. I think the plain
clarity of if() just in many places justifies burning couple of lines
more :)
Yours
-- Matti
--
Matti Vaittinen
Linux kernel developer at ROHM Semiconductors
Oulu Finland
~~ When things go utterly wrong vim users can always type :help! ~~
