[PATCH] mtd: cfi_cmdset_0002: Change erase functions to retry for error

[IKEGAMI Tokunori]

From: Tokunori Ikegami <ikegami at allied-telesis.co.jp>

For the word write functions it is retried for error.
But it is not implemented to retry for the erase functions.
To make sure for the erase functions change to retry as same.

This is needed to prevent the flash erase error caused only once.
It was caused by the error case of chip_good() in the do_erase_oneblock().
Also it was confirmed on the MACRONIX flash device MX29GL512FHT2I-11G.
But the error issue behavior is not able to reproduce at this moment.
The flash controller is parallel Flash interface integrated on BCM53003.

Signed-off-by: Tokunori Ikegami <ikegami at allied-telesis.co.jp>
Cc: Chris Packham <chris.packham at alliedtelesis.co.nz>
Cc: Brian Norris <computersforpeace at gmail.com>
Cc: David Woodhouse <dwmw2 at infradead.org>
Cc: Boris Brezillon <boris.brezillon at free-electrons.com>
Cc: Marek Vasut <marek.vasut at gmail.com>
Cc: Richard Weinberger <richard at nod.at>
Cc: Cyrille Pitchen <cyrille.pitchen at wedev4u.fr>
Cc: linux-mtd at lists.infradead.org
---
 drivers/mtd/chips/cfi_cmdset_0002.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index 56aa6b75213d..f522a856526a 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -43,6 +43,7 @@
 #define FORCE_WORD_WRITE 0
 
 #define MAX_WORD_RETRIES 3
+#define MAX_ERASE_RETRY 3
 
 #define SST49LF004B	        0x0060
 #define SST49LF040B	        0x0050
@@ -2240,6 +2241,7 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
 	unsigned long int adr;
 	DECLARE_WAITQUEUE(wait, current);
 	int ret = 0;
+	int retry_cnt = 0;
 
 	adr = cfi->addr_unlock1;
 
@@ -2257,6 +2259,7 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
 	ENABLE_VPP(map);
 	xip_disable(map, chip, adr);
 
+ retry:
 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
 	cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
@@ -2310,6 +2313,9 @@ static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
 		map_write( map, CMD(0xF0), chip->start );
 		/* FIXME - should have reset delay before continuing */
 
+		if (++retry_cnt <= MAX_ERASE_RETRY)
+			goto retry;
+
 		ret = -EIO;
 	}
 
@@ -2329,6 +2335,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
 	unsigned long timeo = jiffies + HZ;
 	DECLARE_WAITQUEUE(wait, current);
 	int ret = 0;
+	int retry_cnt = 0;
 
 	adr += chip->start;
 
@@ -2346,6 +2353,7 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
 	ENABLE_VPP(map);
 	xip_disable(map, chip, adr);
 
+ retry:
 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
 	cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
@@ -2402,6 +2410,9 @@ static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip,
 		map_write( map, CMD(0xF0), chip->start );
 		/* FIXME - should have reset delay before continuing */
 
+		if (++retry_cnt <= MAX_ERASE_RETRY)
+			goto retry;
+
 		ret = -EIO;
 	}
 
-- 
2.16.1