mtd: nand: Move Samsung specific init/detection logic in nand_samsung.c

Move Samsung specific initialization and detection logic into
nand_samsung.c. This is part of the "separate vendor specific code from
core" cleanup process.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Richard Weinberger <richard@nod.at>

1 files changed, 92 insertions, 0 deletions

diff --git a/drivers/mtd/nand/nand_samsung.c b/drivers/mtd/nand/nand_samsung.c
new file mode 100644
index 0000000..5c259dd
--- /dev/null
+++ b/drivers/mtd/nand/nand_samsung.c
@@ -0,0 +1,92 @@
+/*
+ * Copyright (C) 2017 Free Electrons
+ * Copyright (C) 2017 NextThing Co
+ *
+ * Author: Boris Brezillon <boris.brezillon@free-electrons.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/mtd/nand.h>
+
+static void samsung_nand_decode_id(struct nand_chip *chip)
+{
+	struct mtd_info *mtd = nand_to_mtd(chip);
+
+	/* New Samsung (6 byte ID): Samsung K9GAG08U0F (p.44) */
+	if (chip->id.len == 6 && !nand_is_slc(chip) &&
+	    chip->id.data[5] != 0x00) {
+		u8 extid = chip->id.data[3];
+
+		/* Get pagesize */
+		mtd->writesize = 2048 << (extid & 0x03);
+
+		extid >>= 2;
+
+		/* Get oobsize */
+		switch (((extid >> 2) & 0x4) | (extid & 0x3)) {
+		case 1:
+			mtd->oobsize = 128;
+			break;
+		case 2:
+			mtd->oobsize = 218;
+			break;
+		case 3:
+			mtd->oobsize = 400;
+			break;
+		case 4:
+			mtd->oobsize = 436;
+			break;
+		case 5:
+			mtd->oobsize = 512;
+			break;
+		case 6:
+			mtd->oobsize = 640;
+			break;
+		default:
+			/*
+			 * We should never reach this case, but if that
+			 * happens, this probably means Samsung decided to use
+			 * a different extended ID format, and we should find
+			 * a way to support it.
+			 */
+			WARN(1, "Invalid OOB size value");
+			break;
+		}
+
+		/* Get blocksize */
+		extid >>= 2;
+		mtd->erasesize = (128 * 1024) <<
+				 (((extid >> 1) & 0x04) | (extid & 0x03));
+	} else {
+		nand_decode_ext_id(chip);
+	}
+}
+
+static int samsung_nand_init(struct nand_chip *chip)
+{
+	struct mtd_info *mtd = nand_to_mtd(chip);
+
+	if (mtd->writesize > 512)
+		chip->options |= NAND_SAMSUNG_LP_OPTIONS;
+
+	if (!nand_is_slc(chip))
+		chip->bbt_options |= NAND_BBT_SCANLASTPAGE;
+	else
+		chip->bbt_options |= NAND_BBT_SCAN2NDPAGE;
+
+	return 0;
+}
+
+const struct nand_manufacturer_ops samsung_nand_manuf_ops = {
+	.detect = samsung_nand_decode_id,
+	.init = samsung_nand_init,
+};