From 7432ed05a3b59e2dc919ab3c74fb2114177bf1a3 Mon Sep 17 00:00:00 2001
From: Simon Guinot <sguinot@lacie.com>
Date: Mon, 2 May 2011 11:01:38 +0000
Subject: [PATCH] sf: macronix: disable write protection when initializing
Signed-off-by: Simon Guinot <sguinot@lacie.com>
---
drivers/mtd/spi/macronix.c | 42 ++++++++++++++++++++++++++++++++++++++
1 file changed, 42 insertions(+)
diff --git a/drivers/mtd/spi/macronix.c b/drivers/mtd/spi/macronix.c
index 96fd5f0052..dacbc28b3e 100644
--- a/drivers/mtd/spi/macronix.c
+++ b/drivers/mtd/spi/macronix.c
@@ -117,6 +117,45 @@ static const struct macronix_spi_flash_params macronix_spi_flash_table[] = {
},
};
+static int macronix_write_status(struct spi_flash *flash, u8 sr)
+{
+ u8 cmd;
+ int ret;
+
+ ret = spi_flash_cmd_write_enable(flash);
+ if (ret < 0) {
+ debug("SF: enabling write failed\n");
+ return ret;
+ }
+
+ cmd = CMD_MX25XX_WRSR;
+ ret = spi_flash_cmd_write(flash->spi, &cmd, 1, &sr, 1);
+ if (ret) {
+ debug("SF: fail to write status register\n");
+ return ret;
+ }
+
+ ret = spi_flash_cmd_wait_ready(flash, SPI_FLASH_PROG_TIMEOUT);
+ if (ret < 0) {
+ debug("SF: write status register timed out\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int macronix_unlock(struct spi_flash *flash)
+{
+ int ret;
+
+ /* Enable status register writing and clear BP# bits */
+ ret = macronix_write_status(flash, 0);
+ if (ret)
+ debug("SF: fail to disable write protection\n");
+
+ return ret;
+}
+
static int macronix_erase(struct spi_flash *flash, u32 offset, size_t len)
{
return spi_flash_cmd_erase(flash, CMD_MX25XX_BE, offset, len);
@@ -157,5 +196,8 @@ struct spi_flash *spi_flash_probe_macronix(struct spi_slave *spi, u8 *idcode)
* params->sectors_per_block;
flash->size = flash->sector_size * params->nr_blocks;
+ /* Clear BP# bits for read-only flash */
+ macronix_unlock(flash);
+
return flash;
}
--
2.39.5