mtd: add support for switching old SST chips into QRY mode

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Gitweb:     http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=4a58948669702639db7acecfa2105c3172d85c93
Commit:     4a58948669702639db7acecfa2105c3172d85c93
Parent:     db5432db81b1775f145945b21428490583ab3e2b
Author:     Guillaume LECERF <foxcore at gmail.com>
AuthorDate: Mon Nov 23 02:10:49 2009 +0100
Committer:  David Woodhouse <David.Woodhouse at intel.com>
CommitDate: Mon Nov 30 11:39:21 2009 +0000

    mtd: add support for switching old SST chips into QRY mode
    
    SST 39VF160x/39VF320x and some old SST chips need a special command
    sequence to enter CFI QueRY mode [1].
    This patch adds the relevant sequence to cfi_qry_mode_on().
    Tested with 39VF3201.
    
    Signed-off-by: Guillaume LECERF <glecerf at gmail.com>
    Signed-off-by: David Woodhouse <David.Woodhouse at intel.com>
---
 drivers/mtd/chips/cfi_util.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/drivers/mtd/chips/cfi_util.c b/drivers/mtd/chips/cfi_util.c
index c5a84fd..ca584d0 100755
--- a/drivers/mtd/chips/cfi_util.c
+++ b/drivers/mtd/chips/cfi_util.c
@@ -71,6 +71,13 @@ int __xipram cfi_qry_mode_on(uint32_t base, struct map_info *map,
 	cfi_send_gen_cmd(0x98, 0x555, base, map, cfi, cfi->device_type, NULL);
 	if (cfi_qry_present(map, base, cfi))
 		return 1;
+	/* some old SST chips, e.g. 39VF160x/39VF320x */
+	cfi_send_gen_cmd(0xF0, 0, base, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0xAA, 0x5555, base, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x55, 0x2AAA, base, map, cfi, cfi->device_type, NULL);
+	cfi_send_gen_cmd(0x98, 0x5555, base, map, cfi, cfi->device_type, NULL);
+	if (cfi_qry_present(map, base, cfi))
+		return 1;
 	/* QRY not found */
 	return 0;
 }