mmc: add module param to set fault injection attributes

Replace setup("fail_mmc_request") and faulty "ifdef KERNEL" with
a simple module_param(). The module param mmc_core.fail_request
may be used to set the fault injection attributes during boot time
or module load time.
Signed-off-by: Per Forlin <per.forlin@linaro.org>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/core/debugfs.c

@@ -20,6 +20,14 @@
 #include "core.h"
 #include "mmc_ops.h"
 
+#ifdef CONFIG_FAIL_MMC_REQUEST
+
+static DECLARE_FAULT_ATTR(fail_default_attr);
+static char *fail_request;
+module_param(fail_request, charp, 0);
+
+#endif /* CONFIG_FAIL_MMC_REQUEST */
+
 /* The debugfs functions are optimized away when CONFIG_DEBUG_FS isn't set. */
 static int mmc_ios_show(struct seq_file *s, void *data)
 {
@@ -168,23 +176,6 @@ static int mmc_clock_opt_set(void *data, u64 val)
 	return 0;
 }
 
-#ifdef CONFIG_FAIL_MMC_REQUEST
-
-static DECLARE_FAULT_ATTR(fail_mmc_request);
-
-#ifdef KERNEL
-/*
- * Internal function. Pass the boot param fail_mmc_request to
- * the setup fault injection attributes routine.
- */
-static int __init setup_fail_mmc_request(char *str)
-{
-	return setup_fault_attr(&fail_mmc_request, str);
-}
-__setup("fail_mmc_request=", setup_fail_mmc_request);
-#endif /* KERNEL */
-#endif /* CONFIG_FAIL_MMC_REQUEST */
-
 DEFINE_SIMPLE_ATTRIBUTE(mmc_clock_fops, mmc_clock_opt_get, mmc_clock_opt_set,
 	"%llu\n");
 
@@ -216,7 +207,9 @@ void mmc_add_host_debugfs(struct mmc_host *host)
 		goto err_node;
 #endif
 #ifdef CONFIG_FAIL_MMC_REQUEST
-	host->fail_mmc_request = fail_mmc_request;
+	if (fail_request)
+		setup_fault_attr(&fail_default_attr, fail_request);
+	host->fail_mmc_request = fail_default_attr;
 	if (IS_ERR(fault_create_debugfs_attr("fail_mmc_request",
 					     root,
 					     &host->fail_mmc_request)))