[PATCH v2 1/5] mtd: spi-nor: notify (Q)SPI controller about protocol change
From: Cyrille Pitchen <hidden>
Date: 2015-07-22 13:17:22
Also in:
linux-devicetree, 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
Once the Quad SPI mode has been enabled on a Micron flash memory, this device expects ALL the following commands to use the SPI 4-4-4 protocol. The (Q)SPI controller needs to be notified about the protocol change so it can adapt and keep on dialoging with the Micron memory. Signed-off-by: Cyrille Pitchen <redacted> --- drivers/mtd/spi-nor/spi-nor.c | 17 +++++++++++++++++ include/linux/mtd/spi-nor.h | 13 +++++++++++++ 2 files changed, 30 insertions(+)
diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index d78831b4422b..93627d4e6be8 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c@@ -163,6 +163,18 @@ static inline int write_disable(struct spi_nor *nor) return nor->write_reg(nor, SPINOR_OP_WRDI, NULL, 0, 0); } +/* + * Notify the (Q)SPI controller about the new protocol to be used. + */ +static inline int spi_nor_set_protocol(struct spi_nor *nor, + enum spi_protocol proto) +{ + if (nor->set_protocol) + return nor->set_protocol(nor, proto); + + return 0; +} + static inline struct spi_nor *mtd_to_spi_nor(struct mtd_info *mtd) { return mtd->priv;
@@ -943,6 +955,11 @@ static int micron_quad_enable(struct spi_nor *nor) return ret; } + /* switch protocol to Quad CMD 4-4-4 */ + ret = spi_nor_set_protocol(nor, SPI_PROTO_4_4_4); + if (ret) + return ret; + ret = spi_nor_wait_till_ready(nor); if (ret) return ret;
diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
index e5409524bb0a..1bf6f11310ef 100644
--- a/include/linux/mtd/spi-nor.h
+++ b/include/linux/mtd/spi-nor.h@@ -87,6 +87,16 @@ enum read_mode { SPI_NOR_QUAD, }; +enum spi_protocol { + SPI_PROTO_1_1_1, /* SPI */ + SPI_PROTO_1_1_2, /* Dual Output */ + SPI_PROTO_1_1_4, /* Quad Output */ + SPI_PROTO_1_2_2, /* Dual IO */ + SPI_PROTO_1_4_4, /* Quad IO */ + SPI_PROTO_2_2_2, /* Dual Command */ + SPI_PROTO_4_4_4, /* Quad Command */ +}; + /** * struct spi_nor_xfer_cfg - Structure for defining a Serial Flash transfer * @wren: command for "Write Enable", or 0x00 for not required
@@ -149,6 +159,7 @@ enum spi_nor_option_flags { * read/write/erase/lock/unlock operations * @read_xfer: [OPTIONAL] the read fundamental primitive * @write_xfer: [OPTIONAL] the writefundamental primitive + * @set_protocol: [OPTIONAL] notify about protocol change * @read_reg: [DRIVER-SPECIFIC] read out the register * @write_reg: [DRIVER-SPECIFIC] write data to the register * @read: [DRIVER-SPECIFIC] read data from the SPI NOR
@@ -185,6 +196,8 @@ struct spi_nor { int (*write_reg)(struct spi_nor *nor, u8 opcode, u8 *buf, int len, int write_enable); + int (*set_protocol)(struct spi_nor *nor, enum spi_protocol proto); + int (*read)(struct spi_nor *nor, loff_t from, size_t len, size_t *retlen, u_char *read_buf); void (*write)(struct spi_nor *nor, loff_t to,
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1.8.2.2