[PATCH v2 4/7] mtd: spi-nor: Split spi_nor_init_params()

From: Tudor.Ambarus
Date: Sat Aug 24 2019 - 08:00:57 EST


From: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>

Add functions to delimit what the chunks of code do:

static void spi_nor_init_params()
{
spi_nor_legacy_init_params()
spi_nor_manufacturer_init_params()
spi_nor_sfdp_init_params()
}

Add descriptions to all methods.

spi_nor_init_params() becomes of type void, as all its children
return void.

Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
---
drivers/mtd/spi-nor/spi-nor.c | 83 ++++++++++++++++++++++++++++++++-----------
1 file changed, 63 insertions(+), 20 deletions(-)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index c9514dfd7d6d..93424f914159 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -4186,7 +4186,34 @@ static void spi_nor_manufacturer_init_params(struct spi_nor *nor)
nor->info->fixups->default_init(nor);
}

-static int spi_nor_init_params(struct spi_nor *nor)
+/**
+ * spi_nor_sfdp_init_params() - Initialize the flash's parameters and settings
+ * based on JESD216 SFDP standard.
+ * @nor: pointer to a 'struct spi-nor'.
+ *
+ * The method has a roll-back mechanism: in case the SFDP parsing fails, the
+ * legacy flash parameters and settings will be restored.
+ */
+static void spi_nor_sfdp_init_params(struct spi_nor *nor)
+{
+ struct spi_nor_flash_parameter sfdp_params;
+
+ memcpy(&sfdp_params, &nor->params, sizeof(sfdp_params));
+
+ if (spi_nor_parse_sfdp(nor, &sfdp_params)) {
+ nor->addr_width = 0;
+ nor->flags &= ~SNOR_F_4B_OPCODES;
+ } else {
+ memcpy(&nor->params, &sfdp_params, sizeof(nor->params));
+ }
+}
+
+/**
+ * spi_nor_legacy_init_params() - Initialize the flash's parameters and settings
+ * based on nor->info data.
+ * @nor: pointer to a 'struct spi-nor'.
+ */
+static void spi_nor_legacy_init_params(struct spi_nor *nor)
{
struct spi_nor_flash_parameter *params = &nor->params;
struct spi_nor_erase_map *map = &params->erase_map;
@@ -4260,25 +4287,43 @@ static int spi_nor_init_params(struct spi_nor *nor)
spi_nor_set_erase_type(&map->erase_type[i], info->sector_size,
SPINOR_OP_SE);
spi_nor_init_uniform_erase_map(map, erase_mask, params->size);
+}

+/**
+ * spi_nor_init_params() - Initialize the flash's parameters and settings.
+ * @nor: pointer to a 'struct spi-nor'.
+ *
+ * The flash parameters and settings are initialized based on a sequence of
+ * calls that are ordered by priority:
+ *
+ * 1/ Legacy flash parameters initialization. The initializations are done
+ * based on nor->info data:
+ * spi_nor_legacy_init_params()
+ *
+ * which can be overwritten by:
+ * 2/ Manufacturer flash parameters initialization. The initializations are
+ * done based on MFR register, or when the decisions can not be done solely
+ * based on MFR, by using specific flash_info tweeks, ->default_init():
+ * spi_nor_manufacturer_init_params()
+ *
+ * which can be overwritten by:
+ * 3/ SFDP flash parameters initialization. JESD216 SFDP is a standard and
+ * should be more accurate that the above.
+ * spi_nor_sfdp_init_params()
+ *
+ * Please not that there is a ->post_bfpt() fixup hook that can overwrite the
+ * flash parameters and settings imediately after parsing the Basic Flash
+ * Parameter Table.
+ */
+static void spi_nor_init_params(struct spi_nor *nor)
+{
+ spi_nor_legacy_init_params(nor);

spi_nor_manufacturer_init_params(nor);

- if ((info->flags & (SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ)) &&
- !(info->flags & SPI_NOR_SKIP_SFDP)) {
- struct spi_nor_flash_parameter sfdp_params;
-
- memcpy(&sfdp_params, params, sizeof(sfdp_params));
-
- if (spi_nor_parse_sfdp(nor, &sfdp_params)) {
- nor->addr_width = 0;
- nor->flags &= ~SNOR_F_4B_OPCODES;
- } else {
- memcpy(params, &sfdp_params, sizeof(*params));
- }
- }
-
- return 0;
+ if ((nor->info->flags & (SPI_NOR_DUAL_READ | SPI_NOR_QUAD_READ)) &&
+ !(nor->info->flags & SPI_NOR_SKIP_SFDP))
+ spi_nor_sfdp_init_params(nor);
}

static int spi_nor_select_read(struct spi_nor *nor,
@@ -4693,10 +4738,8 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
nor->info->flags & SPI_NOR_HAS_LOCK)
nor->params.disable_block_protection = spi_nor_clear_sr_bp;

- /* Parse the Serial Flash Discoverable Parameters table. */
- ret = spi_nor_init_params(nor);
- if (ret)
- return ret;
+ /* Init flash parameters based on flash_info struct and SFDP */
+ spi_nor_init_params(nor);

if (!mtd->name)
mtd->name = dev_name(dev);
--
2.9.5