Allow flashes to specify a hook to enable octal DTR mode. Use this hook
whenever possible to get optimal transfer speeds.
Signed-off-by: Pratyush Yadav <p.ya...@ti.com>
---
drivers/mtd/spi/spi-nor-core.c | 31 +++++++++++++++++++++++++++++++
include/linux/mtd/spi-nor.h | 2 ++
2 files changed, 33 insertions(+)
diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c
index 656dd09ea2..bb860158ae 100644
--- a/drivers/mtd/spi/spi-nor-core.c
+++ b/drivers/mtd/spi/spi-nor-core.c
@@ -2803,10 +2803,41 @@ static int spi_nor_setup(struct spi_nor *nor, const
struct flash_info *info,
return nor->setup(nor, info, params, hwcaps);
}
+/** spi_nor_octal_dtr_enable() - enable Octal DTR I/O if needed
+ * @nor: pointer to a 'struct spi_nor'
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_octal_dtr_enable(struct spi_nor *nor)
+{
+ int ret;
+
+ if (!nor->octal_dtr_enable)
+ return 0;
+
+ if (!(nor->read_proto == SNOR_PROTO_8_8_8_DTR &&
+ nor->write_proto == SNOR_PROTO_8_8_8_DTR))
+ return 0;
+
+ ret = nor->octal_dtr_enable(nor);
+ if (ret)
+ return ret;
+
+ nor->reg_proto = SNOR_PROTO_8_8_8_DTR;
+
+ return 0;
+}
+
static int spi_nor_init(struct spi_nor *nor)
{
int err;
+ err = spi_nor_octal_dtr_enable(nor);
+ if (err) {
+ dev_dbg(nor->dev, "Octal DTR mode not supported\n");
+ return err;
+ }
+
/*
* Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up
* with the software protection bits set
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index f738c5eecc..dbd29d0200 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -474,6 +474,7 @@ struct flash_info;
* @flash_is_locked: [FLASH-SPECIFIC] check if a region of the SPI NOR is
* @quad_enable: [FLASH-SPECIFIC] enables SPI NOR quad mode
* completely locked
+ * @octal_dtr_enable: [FLASH-SPECIFIC] enables SPI NOR octal DTR mode.
* @priv: the private data
*/
struct spi_nor {
@@ -521,6 +522,7 @@ struct spi_nor {
int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len);
int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len);
int (*quad_enable)(struct spi_nor *nor);
+ int (*octal_dtr_enable)(struct spi_nor *nor);
void *priv;
/* Compatibility for spi_flash, remove once sf layer is merged with mtd */
--
2.26.2
