[PATCH/RFC] Create mtdram device at runtime.
Johan Adolfsson
johan.adolfsson at axis.com
Mon May 6 04:49:01 EDT 2002
This time I think I got it right...
The caller of mtdram_init_device() is responsible for allocating the
mtd_info struct and to provide the memoryarea.
The caller is also repsonsible for freeing and deleting the stuff
if needed.
cleanup_mtdram() handles that for the non dynamic case, but otherwise
it's up to the caller, no helper function is provided (nor needed really).
/Johan
---
diff -u -p -r1.1.1.3 mtdram.c
--- linux/drivers/mtd/devices/mtdram.c 23 Apr 2002 13:18:59 -0000 1.1.1.3
+++ linux/drivers/mtd/devices/mtdram.c 6 May 2002 08:31:52 -0000
@@ -108,65 +108,119 @@ static void __exit cleanup_mtdram(void)
{
if (mtd_info) {
del_mtd_device(mtd_info);
+#if CONFIG_MTDRAM_TOTAL_SIZE > 0
if (mtd_info->priv)
#if CONFIG_MTDRAM_ABS_POS > 0
iounmap(mtd_info->priv);
#else
vfree(mtd_info->priv);
#endif
+#endif
kfree(mtd_info);
}
}
+int mtdram_init_device(struct mtd_info *mtd, void *mapped_address,
+ unsigned long size, char *name)
+{
+ memset(mtd, 0, sizeof(*mtd));
+
+ /* Setup the MTD structure */
+ mtd->name = name;
+ mtd->type = MTD_RAM;
+ mtd->flags = MTD_CAP_RAM;
+ mtd->size = size;
+ mtd->erasesize = MTDRAM_ERASE_SIZE;
+ mtd->priv = mapped_address;
+
+ mtd->module = THIS_MODULE;
+ mtd->erase = ram_erase;
+ mtd->point = ram_point;
+ mtd->unpoint = ram_unpoint;
+ mtd->read = ram_read;
+ mtd->write = ram_write;
+
+ if (add_mtd_device(mtd)) {
+ return -EIO;
+ }
+
+ return 0;
+}
+
+#if CONFIG_MTDRAM_TOTAL_SIZE > 0
+#if CONFIG_MTDRAM_ABS_POS > 0
int __init init_mtdram(void)
{
- // Allocate some memory
- mtd_info = (struct mtd_info *)kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
+ void *addr;
+ int err;
+ /* Allocate some memory */
+ mtd_info = (struct mtd_info *)kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
if (!mtd_info)
- return -ENOMEM;
+ return -ENOMEM;
- memset(mtd_info, 0, sizeof(*mtd_info));
+ addr = ioremap(CONFIG_MTDRAM_ABS_POS, MTDRAM_TOTAL_SIZE);
+ if (!addr) {
+ DEBUG(MTD_DEBUG_LEVEL1,
+ "Failed to ioremap) memory region of size %ld at ABS_POS:%ld\n",
+ (long)MTDRAM_TOTAL_SIZE, (long)CONFIG_MTDRAM_ABS_POS);
+ kfree(mtd_info);
+ mtd_info = NULL;
+ return -ENOMEM;
+ }
+ err = mtdram_init_device(mtd_info, addr,
+ MTDRAM_TOTAL_SIZE, "mtdram test device");
+ if (err)
+ {
+ iounmap(addr);
+ kfree(mtd_info);
+ mtd_info = NULL;
+ return err;
+ }
+ memset(mtd_info->priv, 0xff, MTDRAM_TOTAL_SIZE);
+ return err;
+}
- // Setup the MTD structure
- mtd_info->name = "mtdram test device";
- mtd_info->type = MTD_RAM;
- mtd_info->flags = MTD_CAP_RAM;
- mtd_info->size = MTDRAM_TOTAL_SIZE;
- mtd_info->erasesize = MTDRAM_ERASE_SIZE;
-#if CONFIG_MTDRAM_ABS_POS > 0
- mtd_info->priv = ioremap(CONFIG_MTDRAM_ABS_POS, MTDRAM_TOTAL_SIZE);
-#else
- mtd_info->priv = vmalloc(MTDRAM_TOTAL_SIZE);
-#endif
+#else /* CONFIG_MTDRAM_ABS_POS > 0 */
- if (!mtd_info->priv) {
- DEBUG(MTD_DEBUG_LEVEL1, "Failed to vmalloc(/ioremap) memory region of size %ld (ABS_POS:%ld)\n",
(long)MTDRAM_TOTAL_SIZE, (long)CONFIG_MTDRAM_ABS_POS);
- kfree(mtd_info);
- mtd_info = NULL;
+int __init init_mtdram(void)
+{
+ void *addr;
+ int err;
+ /* Allocate some memory */
+ mtd_info = (struct mtd_info *)kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
+ if (!mtd_info)
return -ENOMEM;
- }
- memset(mtd_info->priv, 0xff, MTDRAM_TOTAL_SIZE);
- mtd_info->module = THIS_MODULE;
- mtd_info->erase = ram_erase;
- mtd_info->point = ram_point;
- mtd_info->unpoint = ram_unpoint;
- mtd_info->read = ram_read;
- mtd_info->write = ram_write;
+ addr = vmalloc(MTDRAM_TOTAL_SIZE);
+ if (!addr) {
+ DEBUG(MTD_DEBUG_LEVEL1,
+ "Failed to vmalloc memory region of size %ld\n",
+ (long)MTDRAM_TOTAL_SIZE);
+ kfree(mtd_info);
+ mtd_info = NULL;
+ return -ENOMEM;
+ }
+ err = mtdram_init_device(mtd_info, addr,
+ MTDRAM_TOTAL_SIZE, "mtdram test device");
+ if (err)
+ {
+ vfree(addr);
+ kfree(mtd_info);
+ mtd_info = NULL;
+ return err;
+ }
+ memset(mtd_info->priv, 0xff, MTDRAM_TOTAL_SIZE);
+ return err;
+}
+#endif /* !(CONFIG_MTDRAM_ABS_POS > 0) */
+
+#else /* CONFIG_MTDRAM_TOTAL_SIZE > 0 */
- if (add_mtd_device(mtd_info)) {
-#if CONFIG_MTDRAM_ABS_POS > 0
- iounmap(mtd_info->priv);
-#else
- vfree(mtd_info->priv);
-#endif
- kfree(mtd_info);
- mtd_info = NULL;
- return -EIO;
- }
-
- return 0;
+int __init init_mtdram(void)
+{
+ return 0;
}
+#endif /* !(CONFIG_MTDRAM_TOTAL_SIZE > 0) */
module_init(init_mtdram);
module_exit(cleanup_mtdram);
--- /dev/null Sat Mar 24 05:37:44 2001
+++ linux/include/linux/mtd/mtdram.h Mon May 6 10:02:26 2002
@@ -0,0 +1,10 @@
+#ifndef __MTD_MTDRAM_H__
+#define __MTD_MTDRAM_H__
+
+#ifdef __KERNEL__
+#include <linux/mtd/mtd.h>
+int mtdram_init_device(struct mtd_info *mtd, void *mapped_address,
+ unsigned long size, char *name);
+
+#endif /* __KERNEL__ */
+#endif /* __MTD_MTDRAM_H__ */
--- linux/Documentation/Configure.help 23 Apr 2002 15:46:44 -0000 1.46
+++ linux/Documentation/Configure.help 6 May 2002 08:40:34 -0000
@@ -12639,9 +12639,9 @@ CONFIG_MTD_SLRAM
Debugging RAM test driver
CONFIG_MTD_MTDRAM
- This enables a test MTD device driver which uses vmalloc() to
- provide storage. You probably want to say 'N' unless you're
- testing stuff.
+ This enables a test MTD device driver which uses vmalloc()
+ or an absolute address to provide storage.
+ You probably want to say 'N' unless you're testing stuff.
MTDRAM erase block size in KB
CONFIG_MTDRAM_ERASE_SIZE
@@ -12656,6 +12656,8 @@ CONFIG_MTDRAM_TOTAL_SIZE
emulated by the MTDRAM driver. If the MTDRAM driver is built
as a module, it is also possible to specify this as a parameter when
loading the module.
+ If you want to set the size and position at runtime, set to 0,
+ in that case set the ABS_POS parameter to 0 as well.
SRAM Hexadecimal Absolute position or 0
CONFIG_MTDRAM_ABS_POS
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