If a 16bit NAND is attached, but configured with 8bit nand_base will fail.
Add a flag NAND_BUSWIDTH_UNKNOWN and callback set_buswidth to allow it to
change the configuration to 16bit.
Signed-off-by: Jan Weitzel <j.weit...@phytec.de>
---
drivers/mtd/nand/nand_base.c | 45 ++++++++++++++++++++++++++++++++++++++---
include/linux/mtd/nand.h | 4 +++
2 files changed, 45 insertions(+), 4 deletions(-)
diff --git a/drivers/mtd/nand/nand_base.c b/drivers/mtd/nand/nand_base.c
index c4eca0d..055c710 100644
--- a/drivers/mtd/nand/nand_base.c
+++ b/drivers/mtd/nand/nand_base.c
@@ -1027,6 +1027,23 @@ static void nand_set_defaults(struct nand_chip *chip,
int busw)
}
/*
+ * Override defaults with 16 bit ones
+ */
+static void nand_set_defaults16(struct nand_chip *chip)
+{
+ if (chip->read_byte == nand_read_byte)
+ chip->read_byte = nand_read_byte16;
+#ifdef CONFIG_MTD_WRITE
+ if (chip->write_buf == nand_write_buf)
+ chip->write_buf = nand_write_buf16;
+#endif
+ if (chip->read_buf == nand_read_buf)
+ chip->read_buf = nand_read_buf16;
+ if (chip->verify_buf == nand_verify_buf)
+ chip->verify_buf = nand_verify_buf16;
+}
+
+/*
* Get the flash and manufacturer id and lookup if the type is supported
*/
static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
@@ -1128,9 +1145,12 @@ static struct nand_flash_dev *nand_get_flash_type(struct
mtd_info *mtd,
/*
* Check, if buswidth is correct. Hardware drivers should set
- * chip correct !
+ * chip correct or ask for autodetection!
*/
- if (busw != (chip->options & NAND_BUSWIDTH_16)) {
+ if (chip->options & NAND_BUSWIDTH_UNKNOWN) {
+ printk(KERN_INFO "NAND bus width %d bit detected\n",
+ (type->options & NAND_BUSWIDTH_16) ? 16 : 8);
+ } else if (busw != (chip->options & NAND_BUSWIDTH_16)) {
printk(KERN_INFO "NAND device: Manufacturer ID:"
" 0x%02x, Chip ID: 0x%02x (%s %s)\n", *maf_id,
dev_id, nand_manuf_ids[maf_idx].name, mtd->name);
@@ -1202,8 +1222,18 @@ int nand_scan_ident(struct mtd_info *mtd, int maxchips)
struct nand_chip *chip = mtd->priv;
struct nand_flash_dev *type;
- /* Get buswidth to select the correct functions */
- busw = chip->options & NAND_BUSWIDTH_16;
+ if (chip->options & NAND_BUSWIDTH_UNKNOWN) {
+ if (!chip->set_buswidth) {
+ chip->options &= ~NAND_BUSWIDTH_UNKNOWN;
+ printk(KERN_WARNING "Buswidth unknown, but no callback
to fix it.\n");
+ }
+ /* Detect NAND with 8bit buswidth*/
+ busw = 0;
+ } else {
+ /* Get buswidth to select the correct functions */
+ busw = chip->options & NAND_BUSWIDTH_16;
+ }
+
/* Set the default functions */
nand_set_defaults(chip, busw);
@@ -1216,6 +1246,13 @@ int nand_scan_ident(struct mtd_info *mtd, int maxchips)
return PTR_ERR(type);
}
+ if (chip->options & NAND_BUSWIDTH_UNKNOWN) {
+ chip->set_buswidth(mtd, chip);
+ if (chip->options & NAND_BUSWIDTH_16)
+ /* Change buswidth to 16 bit*/
+ nand_set_defaults16(chip);
+ }
+
/* Check for a chip array */
for (i = 1; i < maxchips; i++) {
chip->select_chip(mtd, i);
diff --git a/include/linux/mtd/nand.h b/include/linux/mtd/nand.h
index 8e20876..184fc69 100644
--- a/include/linux/mtd/nand.h
+++ b/include/linux/mtd/nand.h
@@ -192,6 +192,8 @@ typedef enum {
/* This option is defined if the board driver allocates its own buffers
(e.g. because it needs them DMA-coherent */
#define NAND_OWN_BUFFERS 0x00040000
+/* Buswitdh is currently unknown */
+#define NAND_BUSWIDTH_UNKNOWN 0x00080000
/* Options set by nand scan */
/* Nand scan has allocated controller struct */
#define NAND_CONTROLLER_ALLOC 0x80000000
@@ -358,6 +360,7 @@ struct nand_buffers {
* @errstat: [OPTIONAL] hardware specific function to perform
additional error status checks
* (determine if errors are correctable)
* @write_page: [REPLACEABLE] High-level page write function
+ * @set_buswidth: [BOARDSPECIFIC] hardware specific function to configure
buswidth
*/
struct nand_chip {
@@ -382,6 +385,7 @@ struct nand_chip {
int (*errstat)(struct mtd_info *mtd, struct nand_chip
*this, int state, int status, int page);
int (*write_page)(struct mtd_info *mtd, struct nand_chip
*chip,
const uint8_t *buf, int page, int cached,
int raw);
+ int (*set_buswidth)(struct mtd_info *mtd, struct nand_chip
*this);
int chip_delay;
unsigned int options;
--
1.7.0.4
_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox
