Re: [PATCH 0/5] mtd: spi-nor: move manuf out of the core - batch 0

From: Boris Brezillon
Date: Sun Aug 25 2019 - 07:38:59 EST


On Fri, 23 Aug 2019 15:53:33 +0000
<Tudor.Ambarus@xxxxxxxxxxxxx> wrote:

> From: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
>
> This series is a prerequisite for the effort of moving the
> manufacturer specific code out of the SPI NOR core.
>
> The scope is to move all [FLASH-SPECIFIC] parameters and settings
> from 'struct spi_nor' to 'struct spi_nor_flash_parameter'. We will
> have a clear separation between the SPI NOR layer and the flash
> parameters and settings.
>
> 'struct spi_nor_flash_parameter' describes the hardware capabilities
> and associated settings of the SPI NOR flash memory. It includes
> legacy flash parameters and settings that can be overwritten by the
> spi_nor_fixups hooks, or dynamically when parsing the JESD216
> Serial Flash Discoverable Parameters (SFDP) tables. All SFDP params
> and settings will fit inside 'struct spi_nor_flash_parameter'.

While we're at moving things around, I think it'd make sense to move
all '[DRIVER SPECIFIC]' fields (which are actually SPI NOR controller
driver specific fields) to a separate struct:

struct spi_nor_controller_ops {
int (*prepare)(struct spi_nor *nor, enum spi_nor_ops ops);
void (*unprepare)(struct spi_nor *nor, enum spi_nor_ops ops);
int (*read_reg)(struct spi_nor *nor, u8 opcode, u8 *buf, int len);
int (*write_reg)(struct spi_nor *nor, u8 opcode, u8 *buf, int len);
ssize_t (*read)(struct spi_nor *nor, loff_t from,
size_t len, u_char *read_buf);
ssize_t (*write)(struct spi_nor *nor, loff_t to,
size_t len, const u_char *write_buf);
int (*erase)(struct spi_nor *nor, loff_t offs);
};

struct spi_nor {
...
const struct spi_nor_controller_ops *controller_ops;
...
};

>
> Tested uniform and non-uniform erase on sst26vf064b flash using the
> atmel-quadspi driver.
>
> In order to test this, you'll have to merge v5.3-rc5 in spi-nor/next.
> This patch depends on
> 'commit 834de5c1aa76 ("mtd: spi-nor: Fix the disabling of write protection at init")
>
> Tudor Ambarus (5):
> mtd: spi-nor: Regroup flash parameter and settings
> mtd: spi-nor: Use nor->params
> mtd: spi-nor: Drop quad_enable() from 'struct spi-nor'
> mtd: spi-nor: Move clear_sr_bp() to 'struct spi_nor_flash_parameter'
> mtd: spi-nor: Move erase_map to 'struct spi_nor_flash_parameter'
>
> drivers/mtd/spi-nor/spi-nor.c | 236 ++++++++++++++++-----------------------
> include/linux/mtd/spi-nor.h | 254 ++++++++++++++++++++++++++++--------------
> 2 files changed, 269 insertions(+), 221 deletions(-)
>