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authorAndrzej Hajda <a.hajda@samsung.com>2020-07-13 16:43:21 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-07-30 09:03:43 +0200
commita787e5400a1ceeb0ef92d71ec43aeb35b1fa1334 (patch)
tree3ce6478f5fa4385d4443507ad13231d123579c78 /drivers/base
parent654888327e9f655a9d55ad477a9583e90e8c9b5c (diff)
downloadlinux-a787e5400a1ceeb0ef92d71ec43aeb35b1fa1334.tar.bz2
driver core: add device probe log helper
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 omitted or implemented only partially. dev_err_probe helps to replace such code sequences with simple call, so code: if (err != -EPROBE_DEFER) dev_err(dev, ...); return err; becomes: return dev_err_probe(dev, err, ...); Signed-off-by: Andrzej Hajda <a.hajda@samsung.com> Reviewed-by: Rafael J. Wysocki <rafael@kernel.org> Reviewed-by: Mark Brown <broonie@kernel.org> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Link: https://lore.kernel.org/r/20200713144324.23654-2-a.hajda@samsung.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/base')
-rw-r--r--drivers/base/core.c42
1 files changed, 42 insertions, 0 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 4d05868d9356..1606488ed741 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -4203,6 +4203,48 @@ define_dev_printk_level(_dev_info, KERN_INFO);
#endif
+/**
+ * dev_err_probe - 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 debug or error message depending if the error value is
+ * -EPROBE_DEFER and propagate error upwards.
+ * It replaces code sequence:
+ * if (err != -EPROBE_DEFER)
+ * dev_err(dev, ...);
+ * else
+ * dev_dbg(dev, ...);
+ * return err;
+ * with
+ * return dev_err_probe(dev, err, ...);
+ *
+ * Returns @err.
+ *
+ */
+int dev_err_probe(const struct device *dev, int err, const char *fmt, ...)
+{
+ struct va_format vaf;
+ va_list args;
+
+ va_start(args, fmt);
+ vaf.fmt = fmt;
+ vaf.va = &args;
+
+ if (err != -EPROBE_DEFER)
+ dev_err(dev, "error %d: %pV", err, &vaf);
+ else
+ dev_dbg(dev, "error %d: %pV", err, &vaf);
+
+ va_end(args);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(dev_err_probe);
+
static inline bool fwnode_is_primary(struct fwnode_handle *fwnode)
{
return fwnode && !IS_ERR(fwnode->secondary);