[PATCH] iio: gts-helper: fix error headers

Both industrialio-gts-helper.c and iio-gts-helper.h use error codes
defined in <asm-generic/errno-base.h> (usually included via
<linux/errno.h>), but only industrialio-gts-helper.c includes it. On the
other hand, that file also uses error macros like IS_ERR() and
PTR_ERR(), which are included in <linux/err.h>.

Add the right includes to provide the used elements from the error
headers:

- <linux/errno.h> in iio-gts-helper.h

- <linux/err.h> in industrialio-gts-helper.c, which in turn includes
  <asm/errno.h>, which only includes <asm-generic/errno-base.h>

Signed-off-by: Javier Carrasco <[email protected]>
---
I stumbled upon this while refactoring veml6031x00.c
(which uses IIO GTS) just because clangd threw a couple of errors where
-EINVAL is returned in iio-gts-helper.h

In the end everything compiles anyway, and therefore I have not
added a "Fixes:" tag, but please let me know if that is really required
for something like this. It is also true that if the gts header is
included first, the compiler will throw the same error clangd showed me
and the kernel won't compile... Unlikely to ever happen, though.

I have compiled and tested this implementation with the driver I am
attempting to upstream without any issues.
---
 drivers/iio/industrialio-gts-helper.c | 2 +-
 include/linux/iio/iio-gts-helper.h    | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/industrialio-gts-helper.c b/drivers/iio/industrialio-gts-helper.c
index 4f52dc373abf..af6ed37fb34a 100644
--- a/drivers/iio/industrialio-gts-helper.c
+++ b/drivers/iio/industrialio-gts-helper.c
@@ -5,7 +5,7 @@
  */
 
 #include <linux/device.h>
-#include <linux/errno.h>
+#include <linux/err.h>
 #include <linux/export.h>
 #include <linux/minmax.h>
 #include <linux/module.h>
diff --git a/include/linux/iio/iio-gts-helper.h b/include/linux/iio/iio-gts-helper.h
index 66f830ab9b49..f63a482b82b8 100644
--- a/include/linux/iio/iio-gts-helper.h
+++ b/include/linux/iio/iio-gts-helper.h
@@ -7,6 +7,7 @@
 #ifndef __IIO_GTS_HELPER__
 #define __IIO_GTS_HELPER__
 
+#include <linux/errno.h>
 #include <linux/types.h>
 
 struct device;

---
base-commit: dc59e4fea9d83f03bad6bddf3fa2e52491777482
change-id: 20260814-iio-gts-err-headers-d7ecb6b5ebb7

Best regards,
-- 
Javier Carrasco <[email protected]>