Re: [PATCH 2/7] thermal: of: Use scoped device node handling to simplify thermal_of_trips_init()

From: Dragan Simic
Date: Fri Aug 16 2024 - 22:47:42 EST


On 2024-08-15 09:15, Chen-Yu Tsai wrote:
On Wed, Aug 14, 2024 at 10:17:48PM +0200, Krzysztof Kozlowski wrote:
Obtain the device node reference with scoped/cleanup.h to reduce error
handling and make the code a bit simpler.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
---
drivers/thermal/thermal_of.c | 14 ++++----------
1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/thermal/thermal_of.c b/drivers/thermal/thermal_of.c
index a2278d4ad886..c8ded4462bb8 100644
--- a/drivers/thermal/thermal_of.c
+++ b/drivers/thermal/thermal_of.c
@@ -117,10 +117,9 @@ static int thermal_of_populate_trip(struct device_node *np,
static struct thermal_trip *thermal_of_trips_init(struct device_node *np, int *ntrips)
{
struct thermal_trip *tt;
- struct device_node *trips;
int ret, count;

- trips = of_get_child_by_name(np, "trips");
+ struct device_node *trips __free(device_node) = of_get_child_by_name(np, "trips");
if (!trips) {
pr_err("Failed to find 'trips' node\n");
return ERR_PTR(-EINVAL);
@@ -129,15 +128,12 @@ static struct thermal_trip *thermal_of_trips_init(struct device_node *np, int *n
count = of_get_child_count(trips);
if (!count) {
pr_err("No trip point defined\n");
- ret = -EINVAL;
- goto out_of_node_put;
+ return ERR_PTR(-EINVAL);
}

tt = kzalloc(sizeof(*tt) * count, GFP_KERNEL);
- if (!tt) {
- ret = -ENOMEM;
- goto out_of_node_put;
- }
+ if (!tt)
+ return ERR_PTR(-ENOMEM);

*ntrips = count;

Also drop the "of_node_put(trips);" in the successful path?

Once fixed,

Reviewed-by: Chen-Yu Tsai <wenst@xxxxxxxxxxxx>

And I plan to send a patch on top of this making "tt" auto released,
thereby eliminating the error path.

Ah, with that additional patch in place, I totally agree with
moving "*ntrips = 0" to the top.

@@ -155,8 +151,6 @@ static struct thermal_trip *thermal_of_trips_init(struct device_node *np, int *n
out_kfree:
kfree(tt);
*ntrips = 0;
-out_of_node_put:
- of_node_put(trips);

return ERR_PTR(ret);
}

--
2.43.0