PNP: add CONFIG_PNP_DEBUG_MESSAGES and pnp_dbg()

This adds the core function pnp_dbg() and a new config option to
enable it.

The PNP core debugging messages can be enabled at boot-time with the
"pnp.debug" kernel parameter.

Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/pnp/base.h b/drivers/pnp/base.h
index 9fd7bb9b7dce..5e4e82c82659 100644
--- a/drivers/pnp/base.h
+++ b/drivers/pnp/base.h
@@ -166,3 +166,13 @@ struct pnp_resource *pnp_add_io_resource(struct pnp_dev *dev,
 struct pnp_resource *pnp_add_mem_resource(struct pnp_dev *dev,
                                           resource_size_t start,
                                           resource_size_t end, int flags);
+
+extern int pnp_debug;
+
+#if defined(CONFIG_PNP_DEBUG_MESSAGES)
+#define pnp_dbg(dev, format, arg...)                                    \
+        ({ if (pnp_debug) dev_printk(KERN_DEBUG, dev, format, ## arg); 0; })
+#else
+#define pnp_dbg(dev, format, arg...)                                    \
+        ({ if (0) dev_printk(KERN_DEBUG, dev, format, ## arg); 0; })
+#endif