Commit 72289824 authored by Michael Hennerich's avatar Michael Hennerich Committed by David Woodhouse
Browse files

[MTD] m25p80: fix bug - ATmel spi flash fails to be copied to 

Atmel serial flash tends to power up with the protection status bits set.
http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_item_id=4089



[michael.hennerich@analog.com: remove duplicate code]
Signed-off-by: default avatarMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: default avatarBryan Wu <cooloney@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
parent a8931ef3

drivers/mtd/devices/m25p80.c

+22 −0
Original line number Diff line number Diff line
@@ -33,6 +33,7 @@ 
/* Flash opcodes. */

#define	OPCODE_WREN		0x06	/* Write enable */

#define	OPCODE_RDSR		0x05	/* Read status register */

#define	OPCODE_WRSR		0x01	/* Write status register 1 byte */

#define	OPCODE_NORM_READ	0x03	/* Read data bytes (low frequency) */

#define	OPCODE_FAST_READ	0x0b	/* Read data bytes (high frequency) */

#define	OPCODE_PP		0x02	/* Page program (up to 256 bytes) */
@@ -112,6 +113,17 @@ static int read_sr(struct m25p *flash) 
	return val;

}



/*

 * Write status register 1 byte

 * Returns negative if error occurred.

 */

static int write_sr(struct m25p *flash, u8 val)

{

	flash->command[0] = OPCODE_WRSR;

	flash->command[1] = val;



	return spi_write(flash->spi, flash->command, 2);

}



/*

 * Set write enable latch with Write Enable command.
@@ -589,6 +601,16 @@ static int __devinit m25p_probe(struct spi_device *spi) 
	mutex_init(&flash->lock);

	dev_set_drvdata(&spi->dev, flash);



	/*

	 * Atmel serial flash tend to power up

	 * with the software protection bits set

	 */



	if (info->jedec_id >> 16 == 0x1f) {

		write_enable(flash);

		write_sr(flash, 0);

	}



	if (data && data->name)

		flash->mtd.name = data->name;

	else

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