[PATCH v2 10/11] mtd: spi-nor: enable octal DTR mode when possible
From: Pratyush Yadav <hidden>
Date: 2020-02-26 09:38:06
Also in:
linux-spi, lkml
Subsystem:
memory technology devices (mtd), spi nor subsystem, the rest · Maintainers:
Miquel Raynal, Richard Weinberger, Vignesh Raghavendra, Pratyush Yadav, Michael Walle, Linus Torvalds
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 <redacted> --- drivers/mtd/spi-nor/spi-nor.c | 31 +++++++++++++++++++++++++++++++ include/linux/mtd/spi-nor.h | 2 ++ 2 files changed, 33 insertions(+)
diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 06cfc525260c..fdcc1b4abc3f 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c@@ -5184,6 +5184,31 @@ static void spi_nor_init_params(struct spi_nor *nor) spi_nor_late_init_params(nor); } +/** 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->params.octal_dtr_enable) + return 0; + + if (!(spi_nor_get_protocol_width(nor->read_proto) == 8 || + spi_nor_get_protocol_width(nor->write_proto) == 8)) + return 0; + + ret = nor->params.octal_dtr_enable(nor); + if (ret) + return ret; + + nor->reg_proto = SNOR_PROTO_8_8_8_DTR; + + return 0; +} + /** * spi_nor_quad_enable() - enable Quad I/O if needed. * @nor: pointer to a 'struct spi_nor'
@@ -5223,6 +5248,12 @@ 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 mode not supported\n"); + return err; + } + err = spi_nor_quad_enable(nor); if (err) { dev_dbg(nor->dev, "quad mode not supported\n");
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index f54dbd0f86ab..c653f6713cfc 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h@@ -526,6 +526,7 @@ struct spi_nor_locking_ops { * higher index in the array, the higher priority. * @erase_map: the erase map parsed from the SFDP Sector Map Parameter * Table. + * @octal_dtr_enable: enables SPI NOR octal DTR mode. * @quad_enable: enables SPI NOR quad mode. * @set_4byte: puts the SPI NOR in 4 byte addressing mode. * @convert_addr: converts an absolute address into something the flash
@@ -549,6 +550,7 @@ struct spi_nor_flash_parameter { struct spi_nor_erase_map erase_map; + int (*octal_dtr_enable)(struct spi_nor *nor); int (*quad_enable)(struct spi_nor *nor); int (*set_4byte)(struct spi_nor *nor, bool enable); u32 (*convert_addr)(struct spi_nor *nor, u32 addr);
--
2.25.0