| Message ID | 1492011271-15099-1-git-send-email-andrew@lunn.ch |
|---|---|
| State | Accepted |
| Delegated to: | Brian Norris |
| Headers | show |
Le 12/04/2017 à 17:34, Andrew Lunn a écrit : > The Microchip 23k256 is a 32K Byte SRAM connected via SPI. > > Signed-off-by: Andrew Lunn <andrew@lunn.ch> > Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com> Reviewed-by: Cyrille Pitchen <cyrille.pitchen@atmel.com> > --- > v4: > Fix block comment format > Fix parameter indentation > Remove double blank line > --- > drivers/mtd/devices/Kconfig | 10 +++ > drivers/mtd/devices/Makefile | 1 + > drivers/mtd/devices/mchp23k256.c | 182 +++++++++++++++++++++++++++++++++++++++ > 3 files changed, 193 insertions(+) > create mode 100644 drivers/mtd/devices/mchp23k256.c > > diff --git a/drivers/mtd/devices/Kconfig b/drivers/mtd/devices/Kconfig > index 58329d2dacd1..6def5445e03e 100644 > --- a/drivers/mtd/devices/Kconfig > +++ b/drivers/mtd/devices/Kconfig > @@ -95,6 +95,16 @@ config MTD_M25P80 > if you want to specify device partitioning or to use a device which > doesn't support the JEDEC ID instruction. > > +config MTD_MCHP23K256 > + tristate "Microchip 23K256 SRAM" > + depends on SPI_MASTER > + help > + This enables access to Microchip 23K256 SRAM chips, using SPI. > + > + Set up your spi devices with the right board-specific > + platform data, or a device tree description if you want to > + specify device partitioning > + > config MTD_SPEAR_SMI > tristate "SPEAR MTD NOR Support through SMI controller" > depends on PLAT_SPEAR > diff --git a/drivers/mtd/devices/Makefile b/drivers/mtd/devices/Makefile > index 7912d3a0ee34..f0f767624cc6 100644 > --- a/drivers/mtd/devices/Makefile > +++ b/drivers/mtd/devices/Makefile > @@ -12,6 +12,7 @@ obj-$(CONFIG_MTD_LART) += lart.o > obj-$(CONFIG_MTD_BLOCK2MTD) += block2mtd.o > obj-$(CONFIG_MTD_DATAFLASH) += mtd_dataflash.o > obj-$(CONFIG_MTD_M25P80) += m25p80.o > +obj-$(CONFIG_MTD_MCHP23K256) += mchp23k256.o > obj-$(CONFIG_MTD_SPEAR_SMI) += spear_smi.o > obj-$(CONFIG_MTD_SST25L) += sst25l.o > obj-$(CONFIG_MTD_BCM47XXSFLASH) += bcm47xxsflash.o > diff --git a/drivers/mtd/devices/mchp23k256.c b/drivers/mtd/devices/mchp23k256.c > new file mode 100644 > index 000000000000..ed3d1724e5de > --- /dev/null > +++ b/drivers/mtd/devices/mchp23k256.c > @@ -0,0 +1,182 @@ > +/* > + * mchp23k256.c > + * > + * Driver for Microchip 23k256 SPI RAM chips > + * > + * Copyright © 20016 Andrew Lunn <andrew@lunn.ch> > + * > + * This code is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + */ > +#include <linux/device.h> > +#include <linux/module.h> > +#include <linux/mtd/mtd.h> > +#include <linux/mtd/partitions.h> > +#include <linux/mutex.h> > +#include <linux/sched.h> > +#include <linux/sizes.h> > +#include <linux/spi/flash.h> > +#include <linux/spi/spi.h> > + > +struct mchp23k256_flash { > + struct spi_device *spi; > + struct mutex lock; > + struct mtd_info mtd; > +}; > + > +#define MCHP23K256_CMD_WRITE_STATUS 0x01 > +#define MCHP23K256_CMD_WRITE 0x02 > +#define MCHP23K256_CMD_READ 0x03 > +#define MCHP23K256_MODE_SEQ BIT(6) > + > +#define to_mchp23k256_flash(x) container_of(x, struct mchp23k256_flash, mtd) > + > +static int mchp23k256_write(struct mtd_info *mtd, loff_t to, size_t len, > + size_t *retlen, const unsigned char *buf) > +{ > + struct mchp23k256_flash *flash = to_mchp23k256_flash(mtd); > + struct spi_transfer transfer[2] = {}; > + struct spi_message message; > + unsigned char command[3]; > + > + spi_message_init(&message); > + > + command[0] = MCHP23K256_CMD_WRITE; > + command[1] = to >> 8; > + command[2] = to; > + > + transfer[0].tx_buf = command; > + transfer[0].len = sizeof(command); > + spi_message_add_tail(&transfer[0], &message); > + > + transfer[1].tx_buf = buf; > + transfer[1].len = len; > + spi_message_add_tail(&transfer[1], &message); > + > + mutex_lock(&flash->lock); > + > + spi_sync(flash->spi, &message); > + > + if (retlen && message.actual_length > sizeof(command)) > + *retlen += message.actual_length - sizeof(command); > + > + mutex_unlock(&flash->lock); > + return 0; > +} > + > +static int mchp23k256_read(struct mtd_info *mtd, loff_t from, size_t len, > + size_t *retlen, unsigned char *buf) > +{ > + struct mchp23k256_flash *flash = to_mchp23k256_flash(mtd); > + struct spi_transfer transfer[2] = {}; > + struct spi_message message; > + unsigned char command[3]; > + > + spi_message_init(&message); > + > + memset(&transfer, 0, sizeof(transfer)); > + command[0] = MCHP23K256_CMD_READ; > + command[1] = from >> 8; > + command[2] = from; > + > + transfer[0].tx_buf = command; > + transfer[0].len = sizeof(command); > + spi_message_add_tail(&transfer[0], &message); > + > + transfer[1].rx_buf = buf; > + transfer[1].len = len; > + spi_message_add_tail(&transfer[1], &message); > + > + mutex_lock(&flash->lock); > + > + spi_sync(flash->spi, &message); > + > + if (retlen && message.actual_length > sizeof(command)) > + *retlen += message.actual_length - sizeof(command); > + > + mutex_unlock(&flash->lock); > + return 0; > +} > + > +/* > + * Set the device into sequential mode. This allows read/writes to the > + * entire SRAM in a single operation > + */ > +static int mchp23k256_set_mode(struct spi_device *spi) > +{ > + struct spi_transfer transfer = {}; > + struct spi_message message; > + unsigned char command[2]; > + > + spi_message_init(&message); > + > + command[0] = MCHP23K256_CMD_WRITE_STATUS; > + command[1] = MCHP23K256_MODE_SEQ; > + > + transfer.tx_buf = command; > + transfer.len = sizeof(command); > + spi_message_add_tail(&transfer, &message); > + > + return spi_sync(spi, &message); > +} > + > +static int mchp23k256_probe(struct spi_device *spi) > +{ > + struct mchp23k256_flash *flash; > + struct flash_platform_data *data; > + int err; > + > + flash = devm_kzalloc(&spi->dev, sizeof(*flash), GFP_KERNEL); > + if (!flash) > + return -ENOMEM; > + > + flash->spi = spi; > + mutex_init(&flash->lock); > + spi_set_drvdata(spi, flash); > + > + err = mchp23k256_set_mode(spi); > + if (err) > + return err; > + > + data = dev_get_platdata(&spi->dev); > + > + flash->mtd.dev.parent = &spi->dev; > + flash->mtd.type = MTD_RAM; > + flash->mtd.flags = MTD_CAP_RAM; > + flash->mtd.writesize = 1; > + flash->mtd.size = SZ_32K; > + flash->mtd._read = mchp23k256_read; > + flash->mtd._write = mchp23k256_write; > + > + err = mtd_device_parse_register(&flash->mtd, NULL, NULL, > + data ? data->parts : NULL, > + data ? data->nr_parts : 0); > + if (err) > + return err; > + > + return 0; > +} > + > +static int mchp23k256_remove(struct spi_device *spi) > +{ > + struct mchp23k256_flash *flash = spi_get_drvdata(spi); > + > + return mtd_device_unregister(&flash->mtd); > +} > + > +static struct spi_driver mchp23k256_driver = { > + .driver = { > + .name = "mchp23k256", > + }, > + .probe = mchp23k256_probe, > + .remove = mchp23k256_remove, > +}; > + > +module_spi_driver(mchp23k256_driver); > + > +MODULE_DESCRIPTION("MTD SPI driver for MCHP23K256 RAM chips"); > +MODULE_AUTHOR("Andrew Lunn <andre@lunn.ch>"); > +MODULE_LICENSE("GPL v2"); > +MODULE_ALIAS("spi:mchp23k256"); >
Hi, On Wed, Apr 12, 2017 at 05:34:31PM +0200, Andrew Lunn wrote: > The Microchip 23k256 is a 32K Byte SRAM connected via SPI. > > Signed-off-by: Andrew Lunn <andrew@lunn.ch> > Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com> I've applied this to l2-mtd.git/next, for 4.13, with one small tweak, and some other small comments below. > --- > v4: > Fix block comment format > Fix parameter indentation > Remove double blank line > --- > drivers/mtd/devices/Kconfig | 10 +++ > drivers/mtd/devices/Makefile | 1 + > drivers/mtd/devices/mchp23k256.c | 182 +++++++++++++++++++++++++++++++++++++++ > 3 files changed, 193 insertions(+) > create mode 100644 drivers/mtd/devices/mchp23k256.c > ... > diff --git a/drivers/mtd/devices/mchp23k256.c b/drivers/mtd/devices/mchp23k256.c > new file mode 100644 > index 000000000000..ed3d1724e5de > --- /dev/null > +++ b/drivers/mtd/devices/mchp23k256.c > @@ -0,0 +1,182 @@ > +/* > + * mchp23k256.c > + * > + * Driver for Microchip 23k256 SPI RAM chips > + * > + * Copyright © 20016 Andrew Lunn <andrew@lunn.ch> Whoa, you have a time machine, and you used it to write this driver?? I'm in awe! I've deleted a zero from this :) > + * > + * This code is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + */ ... > +static int mchp23k256_read(struct mtd_info *mtd, loff_t from, size_t len, > + size_t *retlen, unsigned char *buf) > +{ > + struct mchp23k256_flash *flash = to_mchp23k256_flash(mtd); > + struct spi_transfer transfer[2] = {}; > + struct spi_message message; > + unsigned char command[3]; > + > + spi_message_init(&message); > + > + memset(&transfer, 0, sizeof(transfer)); Isn't this memset redundant, since you're initialized the struct above? (I haven't touched this when applying.) > + command[0] = MCHP23K256_CMD_READ; > + command[1] = from >> 8; > + command[2] = from; > + > + transfer[0].tx_buf = command; > + transfer[0].len = sizeof(command); > + spi_message_add_tail(&transfer[0], &message); > + > + transfer[1].rx_buf = buf; > + transfer[1].len = len; > + spi_message_add_tail(&transfer[1], &message); > + > + mutex_lock(&flash->lock); > + > + spi_sync(flash->spi, &message); > + > + if (retlen && message.actual_length > sizeof(command)) > + *retlen += message.actual_length - sizeof(command); > + > + mutex_unlock(&flash->lock); > + return 0; > +} ... Brian
> > diff --git a/drivers/mtd/devices/mchp23k256.c b/drivers/mtd/devices/mchp23k256.c > > new file mode 100644 > > index 000000000000..ed3d1724e5de > > --- /dev/null > > +++ b/drivers/mtd/devices/mchp23k256.c > > @@ -0,0 +1,182 @@ > > +/* > > + * mchp23k256.c > > + * > > + * Driver for Microchip 23k256 SPI RAM chips > > + * > > + * Copyright © 20016 Andrew Lunn <andrew@lunn.ch> > > Whoa, you have a time machine, and you used it to write this driver?? > I'm in awe! > > I've deleted a zero from this :) Great, thanks. > > +static int mchp23k256_read(struct mtd_info *mtd, loff_t from, size_t len, > > + size_t *retlen, unsigned char *buf) > > +{ > > + struct mchp23k256_flash *flash = to_mchp23k256_flash(mtd); > > + struct spi_transfer transfer[2] = {}; > > + struct spi_message message; > > + unsigned char command[3]; > > + > > + spi_message_init(&message); > > + > > + memset(&transfer, 0, sizeof(transfer)); > > Isn't this memset redundant, since you're initialized the struct above? > > (I haven't touched this when applying.) I think was getting compiler warnings somewhere. Used but not set. I could of been too liberal spreading around the memset's. Thanks Andrew
diff --git a/drivers/mtd/devices/Kconfig b/drivers/mtd/devices/Kconfig index 58329d2dacd1..6def5445e03e 100644 --- a/drivers/mtd/devices/Kconfig +++ b/drivers/mtd/devices/Kconfig @@ -95,6 +95,16 @@ config MTD_M25P80 if you want to specify device partitioning or to use a device which doesn't support the JEDEC ID instruction. +config MTD_MCHP23K256 + tristate "Microchip 23K256 SRAM" + depends on SPI_MASTER + help + This enables access to Microchip 23K256 SRAM chips, using SPI. + + Set up your spi devices with the right board-specific + platform data, or a device tree description if you want to + specify device partitioning + config MTD_SPEAR_SMI tristate "SPEAR MTD NOR Support through SMI controller" depends on PLAT_SPEAR diff --git a/drivers/mtd/devices/Makefile b/drivers/mtd/devices/Makefile index 7912d3a0ee34..f0f767624cc6 100644 --- a/drivers/mtd/devices/Makefile +++ b/drivers/mtd/devices/Makefile @@ -12,6 +12,7 @@ obj-$(CONFIG_MTD_LART) += lart.o obj-$(CONFIG_MTD_BLOCK2MTD) += block2mtd.o obj-$(CONFIG_MTD_DATAFLASH) += mtd_dataflash.o obj-$(CONFIG_MTD_M25P80) += m25p80.o +obj-$(CONFIG_MTD_MCHP23K256) += mchp23k256.o obj-$(CONFIG_MTD_SPEAR_SMI) += spear_smi.o obj-$(CONFIG_MTD_SST25L) += sst25l.o obj-$(CONFIG_MTD_BCM47XXSFLASH) += bcm47xxsflash.o diff --git a/drivers/mtd/devices/mchp23k256.c b/drivers/mtd/devices/mchp23k256.c new file mode 100644 index 000000000000..ed3d1724e5de --- /dev/null +++ b/drivers/mtd/devices/mchp23k256.c @@ -0,0 +1,182 @@ +/* + * mchp23k256.c + * + * Driver for Microchip 23k256 SPI RAM chips + * + * Copyright © 20016 Andrew Lunn <andrew@lunn.ch> + * + * This code is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ +#include <linux/device.h> +#include <linux/module.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/partitions.h> +#include <linux/mutex.h> +#include <linux/sched.h> +#include <linux/sizes.h> +#include <linux/spi/flash.h> +#include <linux/spi/spi.h> + +struct mchp23k256_flash { + struct spi_device *spi; + struct mutex lock; + struct mtd_info mtd; +}; + +#define MCHP23K256_CMD_WRITE_STATUS 0x01 +#define MCHP23K256_CMD_WRITE 0x02 +#define MCHP23K256_CMD_READ 0x03 +#define MCHP23K256_MODE_SEQ BIT(6) + +#define to_mchp23k256_flash(x) container_of(x, struct mchp23k256_flash, mtd) + +static int mchp23k256_write(struct mtd_info *mtd, loff_t to, size_t len, + size_t *retlen, const unsigned char *buf) +{ + struct mchp23k256_flash *flash = to_mchp23k256_flash(mtd); + struct spi_transfer transfer[2] = {}; + struct spi_message message; + unsigned char command[3]; + + spi_message_init(&message); + + command[0] = MCHP23K256_CMD_WRITE; + command[1] = to >> 8; + command[2] = to; + + transfer[0].tx_buf = command; + transfer[0].len = sizeof(command); + spi_message_add_tail(&transfer[0], &message); + + transfer[1].tx_buf = buf; + transfer[1].len = len; + spi_message_add_tail(&transfer[1], &message); + + mutex_lock(&flash->lock); + + spi_sync(flash->spi, &message); + + if (retlen && message.actual_length > sizeof(command)) + *retlen += message.actual_length - sizeof(command); + + mutex_unlock(&flash->lock); + return 0; +} + +static int mchp23k256_read(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, unsigned char *buf) +{ + struct mchp23k256_flash *flash = to_mchp23k256_flash(mtd); + struct spi_transfer transfer[2] = {}; + struct spi_message message; + unsigned char command[3]; + + spi_message_init(&message); + + memset(&transfer, 0, sizeof(transfer)); + command[0] = MCHP23K256_CMD_READ; + command[1] = from >> 8; + command[2] = from; + + transfer[0].tx_buf = command; + transfer[0].len = sizeof(command); + spi_message_add_tail(&transfer[0], &message); + + transfer[1].rx_buf = buf; + transfer[1].len = len; + spi_message_add_tail(&transfer[1], &message); + + mutex_lock(&flash->lock); + + spi_sync(flash->spi, &message); + + if (retlen && message.actual_length > sizeof(command)) + *retlen += message.actual_length - sizeof(command); + + mutex_unlock(&flash->lock); + return 0; +} + +/* + * Set the device into sequential mode. This allows read/writes to the + * entire SRAM in a single operation + */ +static int mchp23k256_set_mode(struct spi_device *spi) +{ + struct spi_transfer transfer = {}; + struct spi_message message; + unsigned char command[2]; + + spi_message_init(&message); + + command[0] = MCHP23K256_CMD_WRITE_STATUS; + command[1] = MCHP23K256_MODE_SEQ; + + transfer.tx_buf = command; + transfer.len = sizeof(command); + spi_message_add_tail(&transfer, &message); + + return spi_sync(spi, &message); +} + +static int mchp23k256_probe(struct spi_device *spi) +{ + struct mchp23k256_flash *flash; + struct flash_platform_data *data; + int err; + + flash = devm_kzalloc(&spi->dev, sizeof(*flash), GFP_KERNEL); + if (!flash) + return -ENOMEM; + + flash->spi = spi; + mutex_init(&flash->lock); + spi_set_drvdata(spi, flash); + + err = mchp23k256_set_mode(spi); + if (err) + return err; + + data = dev_get_platdata(&spi->dev); + + flash->mtd.dev.parent = &spi->dev; + flash->mtd.type = MTD_RAM; + flash->mtd.flags = MTD_CAP_RAM; + flash->mtd.writesize = 1; + flash->mtd.size = SZ_32K; + flash->mtd._read = mchp23k256_read; + flash->mtd._write = mchp23k256_write; + + err = mtd_device_parse_register(&flash->mtd, NULL, NULL, + data ? data->parts : NULL, + data ? data->nr_parts : 0); + if (err) + return err; + + return 0; +} + +static int mchp23k256_remove(struct spi_device *spi) +{ + struct mchp23k256_flash *flash = spi_get_drvdata(spi); + + return mtd_device_unregister(&flash->mtd); +} + +static struct spi_driver mchp23k256_driver = { + .driver = { + .name = "mchp23k256", + }, + .probe = mchp23k256_probe, + .remove = mchp23k256_remove, +}; + +module_spi_driver(mchp23k256_driver); + +MODULE_DESCRIPTION("MTD SPI driver for MCHP23K256 RAM chips"); +MODULE_AUTHOR("Andrew Lunn <andre@lunn.ch>"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("spi:mchp23k256");