mtd: cfi_cmdset_0002: add CFI detection for SST 39VF{16, 32}xx chips

SST 39VF{16,32}xx chips use the 0x0701 command set, fully compatible
with the AMD one. This patch adds support for detecting them in CFI
mode.

Signed-off-by: Guillaume LECERF <glecerf@gmail.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/chips/cfi_cmdset_0002.c b/drivers/mtd/chips/cfi_cmdset_0002.c
index c27dd1c..b7d821d 100644
--- a/drivers/mtd/chips/cfi_cmdset_0002.c
+++ b/drivers/mtd/chips/cfi_cmdset_0002.c
@@ -258,6 +258,31 @@
 	mtd->flags |= MTD_POWERUP_LOCK;
 }
 
+static void fixup_old_sst_eraseregion(struct mtd_info *mtd)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	/*
+	 * These flashes report two seperate eraseblock regions based on the
+	 * sector_erase-size and block_erase-size, although they both operate on the
+	 * same memory. This is not allowed according to CFI, so we just pick the
+	 * sector_erase-size.
+	 */
+	cfi->cfiq->NumEraseRegions = 1;
+}
+
+static void fixup_sst39vf(struct mtd_info *mtd, void *param)
+{
+	struct map_info *map = mtd->priv;
+	struct cfi_private *cfi = map->fldrv_priv;
+
+	fixup_old_sst_eraseregion(mtd);
+
+	cfi->addr_unlock1 = 0x5555;
+	cfi->addr_unlock2 = 0x2AAA;
+}
+
 static void fixup_s29gl064n_sectors(struct mtd_info *mtd, void *param)
 {
 	struct map_info *map = mtd->priv;
@@ -280,6 +305,15 @@
 	}
 }
 
+/* Used to fix CFI-Tables of chips without Extended Query Tables */
+static struct cfi_fixup cfi_nopri_fixup_table[] = {
+	{ CFI_MFR_SST, 0x234A, fixup_sst39vf, NULL, }, // SST39VF1602
+	{ CFI_MFR_SST, 0x234B, fixup_sst39vf, NULL, }, // SST39VF1601
+	{ CFI_MFR_SST, 0x235A, fixup_sst39vf, NULL, }, // SST39VF3202
+	{ CFI_MFR_SST, 0x235B, fixup_sst39vf, NULL, }, // SST39VF3201
+	{ 0, 0, NULL, NULL }
+};
+
 static struct cfi_fixup cfi_fixup_table[] = {
 	{ CFI_MFR_ATMEL, CFI_ID_ANY, fixup_convert_atmel_pri, NULL },
 #ifdef AMD_BOOTLOC_BUG
@@ -413,6 +447,7 @@
 			cfi->addr_unlock1 = 0x555;
 			cfi->addr_unlock2 = 0x2aa;
 		}
+		cfi_fixup(mtd, cfi_nopri_fixup_table);
 
 		if (!cfi->addr_unlock1 || !cfi->addr_unlock2) {
 			kfree(mtd);
diff --git a/drivers/mtd/chips/gen_probe.c b/drivers/mtd/chips/gen_probe.c
index 1d56887..75a8f9d 100644
--- a/drivers/mtd/chips/gen_probe.c
+++ b/drivers/mtd/chips/gen_probe.c
@@ -248,6 +248,7 @@
 #endif
 #ifdef CONFIG_MTD_CFI_AMDSTD
 	case P_ID_AMD_STD:
+	case P_ID_SST_OLD:
 		return cfi_cmdset_0002(map, primary);
 #endif
 #ifdef CONFIG_MTD_CFI_STAA