dell-laptop: move dell_smi_error() to dell-smbios

The dell_smi_error() method could be used by modules other than
dell-laptop for convenient translation of SMBIOS request errors into
errno values.  Thus, move it to dell-smbios.
Signed-off-by: Michał Kępień <kernel@kempniu.pl>
Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

drivers/platform/x86/dell-laptop.c

@@ -273,20 +273,6 @@ static const struct dmi_system_id dell_quirks[] __initconst = {
 	{ }
 };
 
-static inline int dell_smi_error(int value)
-{
-	switch (value) {
-	case 0: /* Completed successfully */
-		return 0;
-	case -1: /* Completed with error */
-		return -EIO;
-	case -2: /* Function not supported */
-		return -ENXIO;
-	default: /* Unknown error */
-		return -EINVAL;
-	}
-}
-
 /*
  * Derived from information in smbios-wireless-ctl:
  *

drivers/platform/x86/dell-smbios.c

@@ -16,6 +16,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/dmi.h>
+#include <linux/err.h>
 #include <linux/gfp.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
@@ -39,6 +40,21 @@ static int da_command_code;
 static int da_num_tokens;
 static struct calling_interface_token *da_tokens;
 
+int dell_smi_error(int value)
+{
+	switch (value) {
+	case 0: /* Completed successfully */
+		return 0;
+	case -1: /* Completed with error */
+		return -EIO;
+	case -2: /* Function not supported */
+		return -ENXIO;
+	default: /* Unknown error */
+		return -EINVAL;
+	}
+}
+EXPORT_SYMBOL_GPL(dell_smi_error);
+
 struct calling_interface_buffer *dell_smbios_get_buffer(void)
 {
 	mutex_lock(&buffer_mutex);

drivers/platform/x86/dell-smbios.h

@@ -35,6 +35,8 @@ struct calling_interface_token {
 	};
 };
 
+int dell_smi_error(int value);
+
 struct calling_interface_buffer *dell_smbios_get_buffer(void);
 void dell_smbios_clear_buffer(void);
 void dell_smbios_release_buffer(void);