lkml.org 
[lkml]   [2008]   [Jul]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[RESEND PATCH 2.6.26-git 1/2] MTD DataFlash: bugfix, binary page sizes now handled (v3)
Date
From: Michael Hennerich <michael.hennerich@analog.com>

This fixes a bug in handling certain newer DataFlash chips (at45db321d
and at45db642d have current Linux users) when they were configured to
use binary page sizes (possibly at the factory).

- Use JEDEC probing (borrowed from m25p80 driver) to tell if the chip
supports binary page sizes ... if so, then query the chip to tell
whether it's currently using them.

- Print that pagesize during probe; erasesize is still listed in
the /proc/mtd file, useful for making filesystems.

Also fix a pre-existing bug with 2 MBit parts using the wrong pagesize;
these are a bit smaller than Linux would normally use (even shared with
a small FPGA's configuration bitstream).

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

Fix regression (so cmdlinepart works again), update error handling
and comments.
# updated to use dev_name(dev) not dev->bus_id

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
---
drivers/mtd/devices/mtd_dataflash.c | 154 ++++++++++++++++++++++++++++++++++--
1 file changed, 149 insertions(+), 5 deletions(-)
--- a/drivers/mtd/devices/mtd_dataflash.c 2008-06-30 16:44:26.000000000 -0700
+++ b/drivers/mtd/devices/mtd_dataflash.c 2008-06-30 21:38:22.000000000 -0700
@@ -15,6 +15,8 @@
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/mutex.h>
+#include <linux/err.h>
+
#include <linux/spi/spi.h>
#include <linux/spi/flash.h>

@@ -487,7 +489,8 @@ add_dataflash(struct spi_device *spi, ch
device->write = dataflash_write;
device->priv = priv;

- dev_info(&spi->dev, "%s (%d KBytes)\n", name, device->size/1024);
+ dev_info(&spi->dev, "%s (%d KBytes) pagesize %d bytes\n",
+ name, DIV_ROUND_UP(device->size, 1024), pagesize);
dev_set_drvdata(&spi->dev, priv);

if (mtd_has_partitions()) {
@@ -516,12 +519,137 @@ add_dataflash(struct spi_device *spi, ch
return add_mtd_device(device) == 1 ? -ENODEV : 0;
}

+struct flash_info {
+ char *name;
+
+ /* JEDEC id zero means "no ID" (most older chips); otherwise it has
+ * a high byte of zero plus three data bytes: the manufacturer id,
+ * then a two byte device id.
+ */
+ u32 jedec_id;
+
+ /* The size listed here is what works with OP_ERASE_PAGE. */
+ unsigned nr_pages;
+ u16 pagesize;
+ u16 pageoffset;
+
+ u16 flags;
+#define SUP_POW2PS 0x0001 /* supports 2^N byte pages */
+#define IS_POW2PS 0x0002 /* uses 2^N byte pages */
+};
+
+static struct flash_info __devinitdata dataflash_data [] = {
+
+ /*
+ * NOTE: chips with SUP_POW2PS (rev D and up) need two entries,
+ * one with IS_POW2PS and the other without. The entry with the
+ * non-2^N byte page size can't name exact chip revisions without
+ * losing backwards compatibility for cmdlinepart.
+ *
+ * These newer chips also support 128-byte security registers (with
+ * 64 bytes one-time-programmable) and software write-protection.
+ */
+ { "AT45DB011B", 0x1f2200, 512, 264, 9, SUP_POW2PS, },
+ { "at45db011d", 0x1f2200, 512, 256, 8, SUP_POW2PS | IS_POW2PS, },
+
+ { "AT45DB021B", 0x1f2300, 1024, 264, 9, SUP_POW2PS, },
+ { "at45db021d", 0x1f2300, 1024, 256, 8, SUP_POW2PS | IS_POW2PS, },
+
+ { "AT45DB041x", 0x1f2400, 2048, 264, 9, SUP_POW2PS, },
+ { "at45db041d", 0x1f2400, 2048, 256, 8, SUP_POW2PS | IS_POW2PS, },
+
+ { "AT45DB081B", 0x1f2500, 4096, 264, 9, SUP_POW2PS, },
+ { "at45db081d", 0x1f2500, 4096, 256, 8, SUP_POW2PS | IS_POW2PS, },
+
+ { "AT45DB161x", 0x1f2600, 4096, 528, 10, SUP_POW2PS, },
+ { "at45db161d", 0x1f2600, 4096, 512, 9, SUP_POW2PS | IS_POW2PS, },
+
+ { "AT45DB321x", 0x1f2700, 8192, 528, 10, 0, }, /* rev C */
+ { "AT45DB321x", 0x1f2701, 8192, 528, 10, SUP_POW2PS, },
+ { "at45db321d", 0x1f2701, 8192, 512, 9, SUP_POW2PS | IS_POW2PS, },
+
+ { "AT45DB642x", 0x1f2800, 8192, 1056, 11, SUP_POW2PS, },
+ { "at45db642d", 0x1f2800, 8192, 1024, 10, SUP_POW2PS | IS_POW2PS, },
+};
+
+static struct flash_info *__devinit jedec_probe(struct spi_device *spi)
+{
+ int tmp;
+ u8 code = OP_READ_ID;
+ u8 id[3];
+ u32 jedec;
+ struct flash_info *info;
+ int status;
+
+ /*
+ * JEDEC also defines an optional "extended device information"
+ * string for after vendor-specific data, after the three bytes
+ * we use here. Supporting some chips might require using it.
+ *
+ * If the vendor ID isn't Atmel's (0x1f), assume this call failed.
+ * That's not an error; only rev C and newer chips handle it, and
+ * only Atmel sells these chips.
+ */
+ tmp = spi_write_then_read(spi, &code, 1, id, 3);
+ if (tmp < 0) {
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: read ID error %d\n",
+ dev_name(spi->dev), status);
+ return ERR_PTR(tmp);
+ }
+ if (id[0] != 0x1f)
+ return NULL;
+
+ jedec = id[0];
+ jedec = jedec << 8;
+ jedec |= id[1];
+ jedec = jedec << 8;
+ jedec |= id[2];
+
+ for (tmp = 0, info = dataflash_data;
+ tmp < ARRAY_SIZE(dataflash_data);
+ tmp++, info++) {
+ if (info->jedec_id == jedec) {
+ DEBUG(MTD_DEBUG_LEVEL1, "%s: security register"
+ ", sector protect%s\n",
+ dev_name(spi->dev),
+ (info->flags & SUP_POW2PS)
+ ? ", binary pagesize" : ""
+ );
+ if (info->flags & SUP_POW2PS) {
+ status = dataflash_status(spi);
+ if (status < 0) {
+ DEBUG(MTD_DEBUG_LEVEL1,
+ "%s: status error %d\n",
+ dev_name(spi->dev), status);
+ return ERR_PTR(status);
+ }
+ if (status & 0x1) {
+ if (info->flags & IS_POW2PS)
+ return info;
+ } else {
+ if (!(info->flags & IS_POW2PS))
+ return info;
+ }
+ }
+ }
+ }
+
+ /*
+ * Treat unrecognized chips as errors ... we won't know the
+ * right page size (it might be binary) even when we can tell
+ * which density class is involved
+ */
+ dev_warn(&spi->dev, "unrecognized JEDEC id %06x\n", jedec);
+ return ERR_PTR(-ENODEV);
+}
+
/*
- * Detect and initialize DataFlash device:
+ * Detect and initialize DataFlash device, using JEDEC IDs on newer chips
+ * or else the ID code embedded in the status bits:
*
* Device Density ID code #Pages PageSize Offset
* AT45DB011B 1Mbit (128K) xx0011xx (0x0c) 512 264 9
- * AT45DB021B 2Mbit (256K) xx0101xx (0x14) 1025 264 9
+ * AT45DB021B 2Mbit (256K) xx0101xx (0x14) 1024 264 9
* AT45DB041B 4Mbit (512K) xx0111xx (0x1c) 2048 264 9
* AT45DB081B 8Mbit (1M) xx1001xx (0x24) 4096 264 9
* AT45DB0161B 16Mbit (2M) xx1011xx (0x2c) 4096 528 10
@@ -531,8 +659,24 @@ add_dataflash(struct spi_device *spi, ch
*/
static int __devinit dataflash_probe(struct spi_device *spi)
{
- int status;
+ int status;
+ struct flash_info *info;

+ /*
+ * Try to detect dataflash by JEDEC ID. If it succeeds, we
+ * have either a C or D part. D supports pagesize options.
+ */
+ info = jedec_probe(spi);
+ if (IS_ERR(info))
+ return PTR_ERR(info);
+ if (info != NULL)
+ return add_dataflash(spi, info->name, info->nr_pages,
+ info->pagesize, info->pageoffset);
+
+ /*
+ * Older chips support only legacy commands, identifing
+ * capacity using bits in the status byte.
+ */
status = dataflash_status(spi);
if (status <= 0 || status == 0xff) {
DEBUG(MTD_DEBUG_LEVEL1, "%s: status error %d\n",
@@ -551,7 +695,7 @@ static int __devinit dataflash_probe(str
status = add_dataflash(spi, "AT45DB011B", 512, 264, 9);
break;
case 0x14: /* 0 1 0 1 x x */
- status = add_dataflash(spi, "AT45DB021B", 1025, 264, 9);
+ status = add_dataflash(spi, "AT45DB021B", 1024, 264, 9);
break;
case 0x1c: /* 0 1 1 1 x x */
status = add_dataflash(spi, "AT45DB041x", 2048, 264, 9);

\
 
 \ /
  Last update: 2008-07-26 00:55    [W:0.084 / U:0.420 seconds]
©2003-2014 Jasper Spaans. Advertise on this site