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path: root/drivers/mtd/spi-nor/spi-nor.c
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Diffstat (limited to 'drivers/mtd/spi-nor/spi-nor.c')
-rw-r--r--drivers/mtd/spi-nor/spi-nor.c119
1 files changed, 108 insertions, 11 deletions
diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 73172d7f512b..0c2ec1c21434 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -1636,6 +1636,95 @@ static int sr2_bit7_quad_enable(struct spi_nor *nor)
return 0;
}
+/**
+ * spi_nor_clear_sr_bp() - clear the Status Register Block Protection bits.
+ * @nor: pointer to a 'struct spi_nor'
+ *
+ * Read-modify-write function that clears the Block Protection bits from the
+ * Status Register without affecting other bits.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_clear_sr_bp(struct spi_nor *nor)
+{
+ int ret;
+ u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
+
+ ret = read_sr(nor);
+ if (ret < 0) {
+ dev_err(nor->dev, "error while reading status register\n");
+ return ret;
+ }
+
+ write_enable(nor);
+
+ ret = write_sr(nor, ret & ~mask);
+ if (ret) {
+ dev_err(nor->dev, "write to status register failed\n");
+ return ret;
+ }
+
+ ret = spi_nor_wait_till_ready(nor);
+ if (ret)
+ dev_err(nor->dev, "timeout while writing status register\n");
+ return ret;
+}
+
+/**
+ * spi_nor_spansion_clear_sr_bp() - clear the Status Register Block Protection
+ * bits on spansion flashes.
+ * @nor: pointer to a 'struct spi_nor'
+ *
+ * Read-modify-write function that clears the Block Protection bits from the
+ * Status Register without affecting other bits. The function is tightly
+ * coupled with the spansion_quad_enable() function. Both assume that the Write
+ * Register with 16 bits, together with the Read Configuration Register (35h)
+ * instructions are supported.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_spansion_clear_sr_bp(struct spi_nor *nor)
+{
+ int ret;
+ u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
+ u8 sr_cr[2] = {0};
+
+ /* Check current Quad Enable bit value. */
+ ret = read_cr(nor);
+ if (ret < 0) {
+ dev_err(nor->dev,
+ "error while reading configuration register\n");
+ return ret;
+ }
+
+ /*
+ * When the configuration register Quad Enable bit is one, only the
+ * Write Status (01h) command with two data bytes may be used.
+ */
+ if (ret & CR_QUAD_EN_SPAN) {
+ sr_cr[1] = ret;
+
+ ret = read_sr(nor);
+ if (ret < 0) {
+ dev_err(nor->dev,
+ "error while reading status register\n");
+ return ret;
+ }
+ sr_cr[0] = ret & ~mask;
+
+ ret = write_sr_cr(nor, sr_cr);
+ if (ret)
+ dev_err(nor->dev, "16-bit write register failed\n");
+ return ret;
+ }
+
+ /*
+ * If the Quad Enable bit is zero, use the Write Status (01h) command
+ * with one data byte.
+ */
+ return spi_nor_clear_sr_bp(nor);
+}
+
/* Used when the "_ext_id" is two bytes at most */
#define INFO(_jedec_id, _ext_id, _sector_size, _n_sectors, _flags) \
.id = { \
@@ -3660,6 +3749,8 @@ static int spi_nor_init_params(struct spi_nor *nor,
default:
/* Kept only for backward compatibility purpose. */
params->quad_enable = spansion_quad_enable;
+ if (nor->clear_sr_bp)
+ nor->clear_sr_bp = spi_nor_spansion_clear_sr_bp;
break;
}
@@ -3912,17 +4003,13 @@ static int spi_nor_init(struct spi_nor *nor)
{
int err;
- /*
- * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up
- * with the software protection bits set
- */
- if (JEDEC_MFR(nor->info) == SNOR_MFR_ATMEL ||
- JEDEC_MFR(nor->info) == SNOR_MFR_INTEL ||
- JEDEC_MFR(nor->info) == SNOR_MFR_SST ||
- nor->info->flags & SPI_NOR_HAS_LOCK) {
- write_enable(nor);
- write_sr(nor, 0);
- spi_nor_wait_till_ready(nor);
+ if (nor->clear_sr_bp) {
+ err = nor->clear_sr_bp(nor);
+ if (err) {
+ dev_err(nor->dev,
+ "fail to clear block protection bits\n");
+ return err;
+ }
}
if (nor->quad_enable) {
@@ -4047,6 +4134,16 @@ int spi_nor_scan(struct spi_nor *nor, const char *name,
if (info->flags & SPI_S3AN)
nor->flags |= SNOR_F_READY_XSR_RDY;
+ /*
+ * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up
+ * with the software protection bits set.
+ */
+ if (JEDEC_MFR(nor->info) == SNOR_MFR_ATMEL ||
+ JEDEC_MFR(nor->info) == SNOR_MFR_INTEL ||
+ JEDEC_MFR(nor->info) == SNOR_MFR_SST ||
+ nor->info->flags & SPI_NOR_HAS_LOCK)
+ nor->clear_sr_bp = spi_nor_clear_sr_bp;
+
/* Parse the Serial Flash Discoverable Parameters table. */
ret = spi_nor_init_params(nor, &params);
if (ret)