[RESEND PATCH v3 09/20] mtd: spi-nor: Create a ->set_4byte() method

Tudor.Ambarus
2019-08-26T12:09:54Z

From: Boris Brezillon <boris.brezillon@bootlin.com>

The procedure used to enable 4 byte addressing mode depends on the NOR
device, so let's provide a hook so that manufacturer specific handling
can be implemented in a sane way.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
[tudor.ambarus@microchip.com: use nor->params.set_4byte() instead of
nor->set_4byte()]
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
v3: no changes

drivers/mtd/spi-nor/spi-nor.c | 76 ++++++++++++++++++++++---------------------
include/linux/mtd/spi-nor.h | 2 ++
2 files changed, 41 insertions(+), 37 deletions(-)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 1e7f8dc3457d..235e82a121a1 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -633,6 +633,17 @@ static int macronix_set_4byte(struct spi_nor *nor, bool enable)
NULL, 0);
}

+static int st_micron_set_4byte(struct spi_nor *nor, bool enable)
+{
+ int ret;
+
+ write_enable(nor);
+ ret = macronix_set_4byte(nor, enable);
+ write_disable(nor);
+
+ return ret;
+}
+
static int spansion_set_4byte(struct spi_nor *nor, bool enable)
{
nor->bouncebuf[0] = enable << 7;
@@ -667,45 +678,24 @@ static int spi_nor_write_ear(struct spi_nor *nor, u8 ear)
return nor->write_reg(nor, SPINOR_OP_WREAR, nor->bouncebuf, 1);
}

-/* Enable/disable 4-byte addressing mode. */
-static int set_4byte(struct spi_nor *nor, bool enable)
+static int winbond_set_4byte(struct spi_nor *nor, bool enable)
{
- int status;
- bool need_wren = false;
-
- switch (JEDEC_MFR(nor->info)) {
- case SNOR_MFR_ST:
- case SNOR_MFR_MICRON:
- /* Some Micron need WREN command; all will accept it */
- need_wren = true;
- /* fall through */
- case SNOR_MFR_MACRONIX:
- case SNOR_MFR_WINBOND:
- if (need_wren)
- write_enable(nor);
+ int ret;

- status = macronix_set_4byte(nor, enable);
- if (need_wren)
- write_disable(nor);
+ ret = macronix_set_4byte(nor, enable);
+ if (ret || enable)
+ return ret;

- if (!status && !enable &&
- JEDEC_MFR(nor->info) == SNOR_MFR_WINBOND) {
- /*
- * On Winbond W25Q256FV, leaving 4byte mode causes
- * the Extended Address Register to be set to 1, so all
- * 3-byte-address reads come from the second 16M.
- * We must clear the register to enable normal behavior.
- */
- write_enable(nor);
- spi_nor_write_ear(nor, 0);
- write_disable(nor);
- }
+ /*
+ * On Winbond W25Q256FV, leaving 4byte mode causes the Extended Address
+ * Register to be set to 1, so all 3-byte-address reads come from the
+ * second 16M. We must clear the register to enable normal behavior.
+ */
+ write_enable(nor);
+ ret = spi_nor_write_ear(nor, 0);
+ write_disable(nor);

- return status;
- default:
- /* Spansion style */
- return spansion_set_4byte(nor, enable);
- }
+ return ret;
}

static int spi_nor_xread_sr(struct spi_nor *nor, u8 *sr)
@@ -4153,11 +4143,18 @@ static int spi_nor_parse_sfdp(struct spi_nor *nor,
static void macronix_set_default_init(struct spi_nor *nor)
{
nor->params.quad_enable = macronix_quad_enable;
+ nor->params.set_4byte = macronix_set_4byte;
}

static void st_micron_set_default_init(struct spi_nor *nor)
{
nor->params.quad_enable = NULL;
+ nor->params.set_4byte = st_micron_set_4byte;
+}
+
+static void winbond_set_default_init(struct spi_nor *nor)
+{
+ nor->params.set_4byte = winbond_set_4byte;
}

/**
@@ -4178,6 +4175,10 @@ static void spi_nor_manufacturer_init_params(struct spi_nor *nor)
st_micron_set_default_init(nor);
break;

+ case SNOR_MFR_WINBOND:
+ winbond_set_default_init(nor);
+ break;
+
default:
break;
}
@@ -4222,6 +4223,7 @@ static void spi_nor_info_init_params(struct spi_nor *nor)

/* Initialize legacy flash parameters and settings. */
params->quad_enable = spansion_quad_enable;
+ params->set_4byte = spansion_set_4byte;

/* Set SPI NOR sizes. */
params->size = (u64)info->sector_size * info->n_sectors;
@@ -4587,7 +4589,7 @@ static int spi_nor_init(struct spi_nor *nor)
*/
WARN_ONCE(nor->flags & SNOR_F_BROKEN_RESET,
"enabling reset hack; may not recover from unexpected reboots\n");
- set_4byte(nor, true);
+ nor->params.set_4byte(nor, true);
}

return 0;
@@ -4611,7 +4613,7 @@ void spi_nor_restore(struct spi_nor *nor)
/* restore the addressing mode */
if (nor->addr_width == 4 && !(nor->flags & SNOR_F_4B_OPCODES) &&
nor->flags & SNOR_F_BROKEN_RESET)
- set_4byte(nor, false);
+ nor->params.set_4byte(nor, false);
}
EXPORT_SYMBOL_GPL(spi_nor_restore);

diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index a86c0d9fb01d..7da89dd483cb 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h
@@ -482,6 +482,7 @@ struct spi_nor;
* @erase_map: the erase map parsed from the SFDP Sector Map Parameter
* Table.
* @quad_enable: enables SPI NOR quad mode.
+ * @set_4byte: puts the SPI NOR in 4 byte addressing mode.
*/
struct spi_nor_flash_parameter {
u64 size;
@@ -494,6 +495,7 @@ struct spi_nor_flash_parameter {
struct spi_nor_erase_map erase_map;

int (*quad_enable)(struct spi_nor *nor);
+ int (*set_4byte)(struct spi_nor *nor, bool enable);
};

/**
--
2.9.5