u-boot/include/spi_flash.h
Marek Behún a67b3719f3 mtd: spi-flash: Check for zero length in legacy spi_flash_*()
Check for zero length in the legacy spi_flash_read() /
spi_flash_write() / spi_flash_erase() functions.
On zero length, return 0 immediately, don't call the underlying method.

Rationale:
- these legacy functions call the _read(), _write() and _erase() methods
  of struct mtd
- the DM callers of these methods already check for zero length
- making all callers of these methods check for zero length makes it
  possible to remove the check from implementations of these _read(),
  _write() and _erase() methods

Signed-off-by: Marek Behún <marek.behun@nic.cz>
2021-10-23 15:47:33 +05:30

221 lines
5.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Common SPI flash Interface
*
* Copyright (C) 2008 Atmel Corporation
* Copyright (C) 2013 Jagannadha Sutradharudu Teki, Xilinx Inc.
*/
#ifndef _SPI_FLASH_H_
#define _SPI_FLASH_H_
#include <linux/types.h>
#include <linux/mtd/spi-nor.h>
struct udevice;
/* by default ENV use the same parameters than SF command */
#ifndef CONFIG_ENV_SPI_BUS
# define CONFIG_ENV_SPI_BUS CONFIG_SF_DEFAULT_BUS
#endif
#ifndef CONFIG_ENV_SPI_CS
# define CONFIG_ENV_SPI_CS CONFIG_SF_DEFAULT_CS
#endif
#ifndef CONFIG_ENV_SPI_MAX_HZ
# define CONFIG_ENV_SPI_MAX_HZ CONFIG_SF_DEFAULT_SPEED
#endif
#ifndef CONFIG_ENV_SPI_MODE
# define CONFIG_ENV_SPI_MODE CONFIG_SF_DEFAULT_MODE
#endif
struct spi_slave;
struct dm_spi_flash_ops {
int (*read)(struct udevice *dev, u32 offset, size_t len, void *buf);
int (*write)(struct udevice *dev, u32 offset, size_t len,
const void *buf);
int (*erase)(struct udevice *dev, u32 offset, size_t len);
/**
* get_sw_write_prot() - Check state of software write-protect feature
*
* SPI flash chips can lock a region of the flash defined by a
* 'protected area'. This function checks if this protected area is
* defined.
*
* @dev: SPI flash device
* @return 0 if no region is write-protected, 1 if a region is
* write-protected, -ENOSYS if the driver does not implement this,
* other -ve value on error
*/
int (*get_sw_write_prot)(struct udevice *dev);
};
/* Access the serial operations for a device */
#define sf_get_ops(dev) ((struct dm_spi_flash_ops *)(dev)->driver->ops)
#if CONFIG_IS_ENABLED(DM_SPI_FLASH)
/**
* spi_flash_read_dm() - Read data from SPI flash
*
* @dev: SPI flash device
* @offset: Offset into device in bytes to read from
* @len: Number of bytes to read
* @buf: Buffer to put the data that is read
* @return 0 if OK, -ve on error
*/
int spi_flash_read_dm(struct udevice *dev, u32 offset, size_t len, void *buf);
/**
* spi_flash_write_dm() - Write data to SPI flash
*
* @dev: SPI flash device
* @offset: Offset into device in bytes to write to
* @len: Number of bytes to write
* @buf: Buffer containing bytes to write
* @return 0 if OK, -ve on error
*/
int spi_flash_write_dm(struct udevice *dev, u32 offset, size_t len,
const void *buf);
/**
* spi_flash_erase_dm() - Erase blocks of the SPI flash
*
* Note that @len must be a muiltiple of the flash sector size.
*
* @dev: SPI flash device
* @offset: Offset into device in bytes to start erasing
* @len: Number of bytes to erase
* @return 0 if OK, -ve on error
*/
int spi_flash_erase_dm(struct udevice *dev, u32 offset, size_t len);
/**
* spl_flash_get_sw_write_prot() - Check state of software write-protect feature
*
* SPI flash chips can lock a region of the flash defined by a
* 'protected area'. This function checks if this protected area is
* defined.
*
* @dev: SPI flash device
* @return 0 if no region is write-protected, 1 if a region is
* write-protected, -ENOSYS if the driver does not implement this,
* other -ve value on error
*/
int spl_flash_get_sw_write_prot(struct udevice *dev);
/**
* spi_flash_std_probe() - Probe a SPI flash device
*
* This is the standard internal method for probing a SPI flash device to
* determine its type. It can be used in chip-specific drivers which need to
* do this, typically with of-platdata
*
* @dev: SPI-flash device to probe
* @return 0 if OK, -ve on error
*/
int spi_flash_std_probe(struct udevice *dev);
int spi_flash_probe_bus_cs(unsigned int busnum, unsigned int cs,
unsigned int max_hz, unsigned int spi_mode,
struct udevice **devp);
/* Compatibility function - this is the old U-Boot API */
struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int spi_mode);
/* Compatibility function - this is the old U-Boot API */
static inline void spi_flash_free(struct spi_flash *flash)
{
}
static inline int spi_flash_read(struct spi_flash *flash, u32 offset,
size_t len, void *buf)
{
return spi_flash_read_dm(flash->dev, offset, len, buf);
}
static inline int spi_flash_write(struct spi_flash *flash, u32 offset,
size_t len, const void *buf)
{
return spi_flash_write_dm(flash->dev, offset, len, buf);
}
static inline int spi_flash_erase(struct spi_flash *flash, u32 offset,
size_t len)
{
return spi_flash_erase_dm(flash->dev, offset, len);
}
struct sandbox_state;
int sandbox_sf_bind_emul(struct sandbox_state *state, int busnum, int cs,
struct udevice *bus, ofnode node, const char *spec);
void sandbox_sf_unbind_emul(struct sandbox_state *state, int busnum, int cs);
#else
struct spi_flash *spi_flash_probe(unsigned int bus, unsigned int cs,
unsigned int max_hz, unsigned int spi_mode);
void spi_flash_free(struct spi_flash *flash);
static inline int spi_flash_read(struct spi_flash *flash, u32 offset,
size_t len, void *buf)
{
struct mtd_info *mtd = &flash->mtd;
size_t retlen;
if (!len)
return 0;
return mtd->_read(mtd, offset, len, &retlen, buf);
}
static inline int spi_flash_write(struct spi_flash *flash, u32 offset,
size_t len, const void *buf)
{
struct mtd_info *mtd = &flash->mtd;
size_t retlen;
if (!len)
return 0;
return mtd->_write(mtd, offset, len, &retlen, buf);
}
static inline int spi_flash_erase(struct spi_flash *flash, u32 offset,
size_t len)
{
struct mtd_info *mtd = &flash->mtd;
struct erase_info instr;
if (offset % mtd->erasesize || len % mtd->erasesize) {
printf("SF: Erase offset/length not multiple of erase size\n");
return -EINVAL;
}
if (!len)
return 0;
memset(&instr, 0, sizeof(instr));
instr.addr = offset;
instr.len = len;
return mtd->_erase(mtd, &instr);
}
#endif
static inline int spi_flash_protect(struct spi_flash *flash, u32 ofs, u32 len,
bool prot)
{
if (!flash->flash_lock || !flash->flash_unlock)
return -EOPNOTSUPP;
if (prot)
return flash->flash_lock(flash, ofs, len);
else
return flash->flash_unlock(flash, ofs, len);
}
#endif /* _SPI_FLASH_H_ */