[PATCH] mtd: m25p80.c add support for non-JEDEC ID devices

[hartleys]

Hello all,

This patch allows the m25p80 driver to support non-JEDEC ID devices.

It has been tested on an EP93xx based ARM platform with a SST25LF020A
2Mbit SPI Serial Flash device.

Any comments would be appreciated.

Thanks,

Signed-off-by: H Hartley Sweeten <hsweeten at visionengravers.com>

---

diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c
index b35c333..ee6dd52 100644
--- a/drivers/mtd/devices/m25p80.c
+++ b/drivers/mtd/devices/m25p80.c
@@ -41,6 +41,7 @@
 #define	OPCODE_BE_32K		0x52	/* Erase 32KiB block */
 #define	OPCODE_SE		0xd8	/* Sector erase (usually
64KiB) */
 #define	OPCODE_RDID		0x9f	/* Read JEDEC ID */
+#define	OPCODE_RDID_NON_JEDEC	0x90	/* Read non-JEDEC ID */
 
 /* Status Register bits. */
 #define	SR_WIP			1	/* Write in progress */
@@ -507,13 +508,17 @@ static struct flash_info __devinitdata m25p_data
[] = {
 	{ "w25x16", 0xef3015, 64 * 1024, 32, SECT_4K, },
 	{ "w25x32", 0xef3016, 64 * 1024, 64, SECT_4K, },
 	{ "w25x64", 0xef3017, 64 * 1024, 128, SECT_4K, },
+
+	/* Non JEDEC ID SST -- large erase sizes are "overlays",
"sectors" are 4K */
+	{ "sst25lf020a", 0xbf43, 32 * 1024, 8, SECT_4K, },
+	{ "sst25lf040a", 0xbf44, 32 * 1024, 16, SECT_4K, },
 };
 
 static struct flash_info *__devinit jedec_probe(struct spi_device *spi)
 {
 	int			tmp;
-	u8			code = OPCODE_RDID;
-	u8			id[3];
+	u8			code[4];
+	u8			id[4];
 	u32			jedec;
 	struct flash_info	*info;
 
@@ -521,7 +526,8 @@ static struct flash_info *__devinit
jedec_probe(struct spi_device *spi)
 	 * string for after vendor-specific data, after the three bytes
 	 * we use here.  Supporting some chips might require using it.
 	 */
-	tmp = spi_write_then_read(spi, &code, 1, id, 3);
+	code[0] = OPCODE_RDID;
+	tmp = spi_write_then_read(spi, code, 1, id, 3);
 	if (tmp < 0) {
 		DEBUG(MTD_DEBUG_LEVEL0, "%s: error %d reading JEDEC
ID\n",
 			spi->dev.bus_id, tmp);
@@ -540,6 +546,31 @@ static struct flash_info *__devinit
jedec_probe(struct spi_device *spi)
 			return info;
 	}
 	dev_err(&spi->dev, "unrecognized JEDEC id %06x\n", jedec);
+
+	/* Try reading the non-JEDEC Manufacture/Device ID */
+	code[0] = OPCODE_RDID_NON_JEDEC;
+	code[1] = 0x00;
+	code[2] = 0x00;
+	code[3] = 0x00;
+	tmp = spi_write_then_read(spi, code, 4, id, 2);
+	if (tmp < 0) {
+		DEBUG(MTD_DEBUG_LEVEL0, "%s: error %d reading ID\n",
+			spi->dev.bus_id, tmp);
+		return NULL;
+	}
+
+	jedec = id[0];
+	jedec = jedec << 8;
+	jedec |= id[1];
+
+	for (tmp = 0, info = m25p_data;
+			tmp < ARRAY_SIZE(m25p_data);
+			tmp++, info++) {
+		if (info->jedec_id == jedec)
+			return info;
+	}
+	dev_err(&spi->dev, "unrecognized id %04x\n", jedec);
+
 	return NULL;
 }