mtd: merge mtdchar module with mtdcore

The MTD subsystem has historically tried to be as configurable as possible. The
side-effect of this is that its configuration menu is rather large, and we are
gradually shrinking it. For example, we recently merged partitions support with
the mtdcore.

This patch does the next step - it merges the mtdchar module to mtdcore. And in
this case this is not only about eliminating too fine-grained separation and
simplifying the configuration menu. This is also about eliminating seemingly
useless kernel module.

Indeed, mtdchar is a module that allows user-space making use of MTD devices
via /dev/mtd* character devices. If users do not enable it, they simply cannot
use MTD devices at all. They cannot read or write the flash contents. Is it a
sane and useful setup? I believe not. And everyone just enables mtdchar.

Having mtdchar separate is also a little bit harmful. People sometimes miss the
fact that they need to enable an additional configuration option to have
user-space MTD interfaces, and then they wonder why on earth the kernel does
not allow using the flash? They spend time asking around.

Thus, let's just get rid of this module and make it part of mtd core.

Note, mtdchar had additional configuration option to enable OTP interfaces,
which are present on some flashes. I removed that option as well - it saves a
really tiny amount space.

[dwmw2: Strictly speaking, you can mount file systems on MTD devices just
        fine without the mtdchar (or mtdblock) devices; you just can't do
        other manipulations directly on the underlying device. But still I
        agree that it makes sense to make this unconditional. And Yay! we
        get to kill off an instance of checking CONFIG_foo_MODULE, which is
        an abomination that should never happen.]

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

1 files changed, 4 insertions, 16 deletions

diff --git a/drivers/mtd/mtdchar.c b/drivers/mtd/mtdchar.c
index c729252..e0e59bf 100644
--- a/drivers/mtd/mtdchar.c
+++ b/drivers/mtd/mtdchar.c
@@ -38,6 +38,8 @@
 
 #include <asm/uaccess.h>
 
+#include "mtdcore.h"
+
 static DEFINE_MUTEX(mtd_mutex);
 
 /*
@@ -365,7 +367,6 @@ static void mtdchar_erase_callback (struct erase_info *instr)
 	wake_up((wait_queue_head_t *)instr->priv);
 }
 
-#ifdef CONFIG_HAVE_MTD_OTP
 static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
 {
 	struct mtd_info *mtd = mfi->mtd;
@@ -395,9 +396,6 @@ static int otp_select_filemode(struct mtd_file_info *mfi, int mode)
 
 	return 0;
 }
-#else
-# define otp_select_filemode(f,m)	-EOPNOTSUPP
-#endif
 
 static int mtdchar_writeoob(struct file *file, struct mtd_info *mtd,
 	uint64_t start, uint32_t length, void __user *ptr,
@@ -890,7 +888,6 @@ static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
 		break;
 	}
 
-#ifdef CONFIG_HAVE_MTD_OTP
 	case OTPSELECT:
 	{
 		int mode;
@@ -946,7 +943,6 @@ static int mtdchar_ioctl(struct file *file, u_int cmd, u_long arg)
 		ret = mtd_lock_user_prot_reg(mtd, oinfo.start, oinfo.length);
 		break;
 	}
-#endif
 
 	/* This ioctl is being deprecated - it truncates the ECC layout */
 	case ECCGETLAYOUT:
@@ -1242,7 +1238,7 @@ static struct file_system_type mtd_inodefs_type = {
 };
 MODULE_ALIAS_FS("mtd_inodefs");
 
-static int __init init_mtdchar(void)
+int __init init_mtdchar(void)
 {
 	int ret;
 
@@ -1268,18 +1264,10 @@ err_unregister_chdev:
 	return ret;
 }
 
-static void __exit cleanup_mtdchar(void)
+void __exit cleanup_mtdchar(void)
 {
 	unregister_filesystem(&mtd_inodefs_type);
 	__unregister_chrdev(MTD_CHAR_MAJOR, 0, 1 << MINORBITS, "mtd");
 }
 
-module_init(init_mtdchar);
-module_exit(cleanup_mtdchar);
-
-MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
-MODULE_DESCRIPTION("Direct character-device access to MTD devices");
 MODULE_ALIAS_CHARDEV_MAJOR(MTD_CHAR_MAJOR);