[PATCH v1 1/2] driver core: add a wrapper to device probe log helper to return pointer

From: Andy Shevchenko
Date: Mon Feb 14 2022 - 09:32:50 EST


Sometimes the ->probe() function can be split to the core and actual probe
parts. In such cases the core one may return a pointer to the allocated
resource, or error pointer in unsuccessful scenario. Allow that kind of
core function to use dev_err_probe_ptr(), so the following excerpt

ret = bar(...);
if (ret) {
dev_err_probe(dev, ret, ...);
return ERR_PTR(ret);
}

can be replaced with

ret = bar(...);
if (ret)
return dev_err_probe_ptr(dev, ret, ...);

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
include/linux/device.h | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/include/linux/device.h b/include/linux/device.h
index 93459724dcde..8650d3afbe7c 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -14,6 +14,7 @@

#include <linux/dev_printk.h>
#include <linux/energy_model.h>
+#include <linux/err.h>
#include <linux/ioport.h>
#include <linux/kobject.h>
#include <linux/klist.h>
@@ -982,6 +983,13 @@ void device_links_supplier_sync_state_resume(void);
extern __printf(3, 4)
int dev_err_probe(const struct device *dev, int err, const char *fmt, ...);

+/* As above, but returns error pointer */
+static inline __printf(3, 0)
+void *dev_err_probe_ptr(const struct device *dev, int err, const char *fmt, va_list args)
+{
+ return ERR_PTR(dev_err_probe(dev, err, fmt, args));
+}
+
/* Create alias, so I can be autoloaded. */
#define MODULE_ALIAS_CHARDEV(major,minor) \
MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor))
--
2.34.1