On Wed, Jun 24, 2020 at 1:41 PM Andrzej Hajda a.hajda@samsung.com wrote:
During probe every time driver gets resource it should usually check for error printk some message if it is not -EPROBE_DEFER and return the error. This pattern is simple but requires adding few lines after any resource acquisition code, as a result it is often omited or implemented only partially. probe_err helps to replace such code sequences with simple call, so code: if (err != -EPROBE_DEFER) dev_err(dev, ...); return err; becomes: return probe_err(dev, err, ...);
Signed-off-by: Andrzej Hajda a.hajda@samsung.com Reviewed-by: Javier Martinez Canillas javierm@redhat.com Reviewed-by: Mark Brown broonie@kernel.org Reviewed-by: Andy Shevchenko andy.shevchenko@gmail.com
Reviewed-by Rafael J. Wysocki rafael@kernel.org
drivers/base/core.c | 39 +++++++++++++++++++++++++++++++++++++++ include/linux/device.h | 3 +++ 2 files changed, 42 insertions(+)
diff --git a/drivers/base/core.c b/drivers/base/core.c index 67d39a90b45c..ee9da66bff1b 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -3953,6 +3953,45 @@ define_dev_printk_level(_dev_info, KERN_INFO);
#endif
+/**
- probe_err - probe error check and log helper
- @dev: the pointer to the struct device
- @err: error value to test
- @fmt: printf-style format string
- @...: arguments as specified in the format string
- This helper implements common pattern present in probe functions for error
- checking: print message if the error is not -EPROBE_DEFER and propagate it.
- It replaces code sequence:
if (err != -EPROBE_DEFER)
dev_err(dev, ...);
return err;
- with
return probe_err(dev, err, ...);
- Returns @err.
- */
+int probe_err(const struct device *dev, int err, const char *fmt, ...) +{
struct va_format vaf;va_list args;if (err == -EPROBE_DEFER)return err;va_start(args, fmt);vaf.fmt = fmt;vaf.va = &args;dev_err(dev, "error %d: %pV", err, &vaf);va_end(args);return err;+} +EXPORT_SYMBOL_GPL(probe_err);
static inline bool fwnode_is_primary(struct fwnode_handle *fwnode) { return fwnode && !IS_ERR(fwnode->secondary); diff --git a/include/linux/device.h b/include/linux/device.h index 15460a5ac024..40a90d9bf799 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -964,6 +964,9 @@ void device_link_remove(void *consumer, struct device *supplier); void device_links_supplier_sync_state_pause(void); void device_links_supplier_sync_state_resume(void);
+extern __printf(3, 4) +int probe_err(const struct device *dev, int err, const char *fmt, ...);
/* Create alias, so I can be autoloaded. */ #define MODULE_ALIAS_CHARDEV(major,minor) \ MODULE_ALIAS("char-major-" __stringify(major) "-" __stringify(minor)) -- 2.17.1