[PATCH] mtd: Nand Atmel: add On Flash BBT support

[simon polette]

2009/5/26 simon polette <spolette at gmail.com>:
> 2009/5/26 Artem Bityutskiy <dedekind at infradead.org>:
>> On Tue, 2009-05-26 at 11:40 +0200, simon polette wrote:
>>> 2009/5/26 Artem Bityutskiy <dedekind at infradead.org>:
>>> > On Mon, 2009-05-25 at 17:44 +0200, simon polette wrote:
>>> >> +config       MTD_NAND_ATMEL_FLASH_BBT
>>> >> +     bool "Use On-Flash Bad Block Table"
>>> >> +     depends on MTD_NAND_ATMEL
>>> >> +     help
>>> >> +       This enables the On-Flash BBT, which mean that the bad blocks
>>> >> +       will be scanned one time then the BBT will be stored
>>> >> +       in flash, so scanning Nand flash for bad blocks will be no more
>>> >> +       necessary for the next boots.
>>> >> +
>>> >
>>> > I do not think you need a config option for this. It should be
>>> > a module parameter instead.
>>> >
>>> > --
>>> > Best regards,
>>> > Artem Bityutskiy (Битюцкий Артём)
>>> >
>>> >
>>>
>>> Yes, good idea, but do you think that I can keep a config option to
>>> define the default state of that param, it means doing something like
>>> :
>>> #ifdef CONFIG_MTD_NAND_ATMEL_FLASH_BBT
>>> static int use_on_flash_bbt = 1;
>>> #else
>>> static int use_on_flash_bbt = 0;
>>> #endif
>>> module_param(use_on_flash_bbt, int, 0);
>>
>> I think it is generally bad idea if each nand driver will
>> introduce a separate config option for this kind of stuff.
>>
>> You may always boot your kernel with something like
>> atmel_nand.on_flash_bbt=1 in the kernel parameters.
>>
>> --
>> Best regards,
>> Artem Bityutskiy (Битюцкий Артём)
>>
>>
>
> Ok, I asked this question cause it's what have been done in the nand
> diskonchip driver.
> I'll send you a new patch soon.
>
> Best regards,
>
> Simon Polette
> Adeneo - Adetelgroup
>

So here is the new patch :

Signed-off-by: Simon Polette <spolette at adetelgroup.com>
---
 drivers/mtd/nand/atmel_nand.c |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
index 47a33ce..e113594 100644
--- a/drivers/mtd/nand/atmel_nand.c
+++ b/drivers/mtd/nand/atmel_nand.c
@@ -24,6 +24,7 @@

 #include <linux/slab.h>
 #include <linux/module.h>
+#include <linux/moduleparam.h>
 #include <linux/platform_device.h>
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/nand.h>Signed-off-by: Simon Polette
<spolette at adetelgroup.com>
@@ -47,6 +48,9 @@
 #define no_ecc		0
 #endif

+static int on_flash_bbt = 0;
+module_param(on_flash_bbt, int, 0);
+
 /* Register access macros */
 #define ecc_readl(add, reg)				\
 	__raw_readl(add + ATMEL_ECC_##reg)
@@ -465,6 +469,11 @@ static int __init atmel_nand_probe(struct
platform_device *pdev)
 		}
 	}

+	if (on_flash_bbt) {
+		printk("atmel_nand: Use On Flash BBT\n");
+		nand_chip->options |= NAND_USE_FLASH_BBT;
+	}
+
 	/* first scan to find the device and get the page size */
 	if (nand_scan_ident(mtd, 1)) {
 		res = -ENXIO;
-- 
1.6.0.4

--
Best regards,

Simon Polette
Adeneo - Adetelgroup