[PATCH v3 29/32] mtd: spi-nor: Merge spansion Quad Enable methods

Tudor.Ambarus
2019-10-29T11:18:08Z

From: Tudor Ambarus <tudor.ambarus@microchip.com>

Merge
spansion_no_read_cr_quad_enable()
spansion_read_cr_quad_enable()
into
spi_nor_sr2_bit1_quad_enable().

Reduce code duplication by introducing spi_nor_write_16bit_cr_and_check().
The Configuration Register contains bits that can be updated in future:
FREEZE, CMP. Provide a generic method that allows updating all bits
of the Configuration Register.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
drivers/mtd/spi-nor/spi-nor.c | 165 +++++++++++++++++-------------------------
1 file changed, 68 insertions(+), 97 deletions(-)

diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
index 1f7ccd80b8ed..ab028afc503f 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -1055,6 +1055,59 @@ static int spi_nor_write_16bit_sr_and_check(struct spi_nor *nor, u8 sr1)
}

/**
+ * spi_nor_write_16bit_cr_and_check() - Write the Status Register 1 and the
+ * Configuration Register in one shot. Ensure that the byte written in the
+ * Configuration Register match the received value, and that the 16-bit Write
+ * did not affect what was already in the Status Register 1.
+ * @nor: pointer to a 'struct spi_nor'.
+ * @cr: byte value to be written to the Configuration Register.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int spi_nor_write_16bit_cr_and_check(struct spi_nor *nor, u8 cr)
+{
+ int ret;
+ u8 *sr_cr = nor->bouncebuf;
+ u8 sr_written;
+
+ /* Keep the current value of the Status Register 1. */
+ ret = spi_nor_read_sr(nor, &sr_cr[0]);
+ if (ret)
+ return ret;
+
+ sr_cr[1] = cr;
+
+ ret = spi_nor_write_sr(nor, sr_cr, 2);
+ if (ret)
+ return ret;
+
+ sr_written = sr_cr[0];
+
+ ret = spi_nor_read_sr(nor, &sr_cr[0]);
+ if (ret)
+ return ret;
+
+ if (sr_written != sr_cr[0]) {
+ dev_err(nor->dev, "SR1: Read back test failed\n");
+ return -EIO;
+ }
+
+ if (nor->flags & SNOR_F_NO_READ_CR)
+ return 0;
+
+ ret = spi_nor_read_cr(nor, &sr_cr[1]);
+ if (ret)
+ return ret;
+
+ if (cr != sr_cr[1]) {
+ dev_err(nor->dev, "CR: read back test failed\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+/**
* spi_nor_write_sr_and_check() - Write the Status Register 1 and ensure that
* the byte written match the received value without affecting other bits in the
* Status Register 1 and 2.
@@ -2051,111 +2104,29 @@ static int macronix_quad_enable(struct spi_nor *nor)
}

/**
- * spansion_no_read_cr_quad_enable() - set QE bit in Configuration Register.
- * @nor: pointer to a 'struct spi_nor'
+ * spi_nor_sr2_bit1_quad_enable() - set the Quad Enable BIT(1) in the Status
+ * Register 2.
+ * @nor: pointer to a 'struct spi_nor'.
*
- * Set the Quad Enable (QE) bit in the Configuration Register.
- * This function should be used with QSPI memories not supporting the Read
- * Configuration Register (35h) instruction.
- *
- * bit 1 of the Configuration Register is the QE bit for Spansion like QSPI
- * memories.
+ * Bit 1 of the Status Register 2 is the QE bit for Spansion like QSPI memories.
*
* Return: 0 on success, -errno otherwise.
*/
-static int spansion_no_read_cr_quad_enable(struct spi_nor *nor)
+static int spi_nor_sr2_bit1_quad_enable(struct spi_nor *nor)
{
- u8 *sr_cr = nor->bouncebuf;
int ret;
- u8 sr_written;
-
- /* Keep the current value of the Status Register. */
- ret = spi_nor_read_sr(nor, &sr_cr[0]);
- if (ret)
- return ret;
-
- sr_cr[1] = SR2_QUAD_EN_BIT1;
-
- ret = spi_nor_write_sr(nor, sr_cr, 2);
- if (ret)
- return ret;

- sr_written = sr_cr[0];
-
- ret = spi_nor_read_sr(nor, &sr_cr[0]);
- if (ret)
- return ret;
-
- if (sr_cr[0] != sr_written) {
- dev_err(nor->dev, "SR1: Read back test failed\n");
- return -EIO;
- }
-
- return 0;
-}
-
-/**
- * spansion_read_cr_quad_enable() - set QE bit in Configuration Register.
- * @nor: pointer to a 'struct spi_nor'
- *
- * Set the Quad Enable (QE) bit in the Configuration Register.
- * This function should be used with QSPI memories supporting the Read
- * Configuration Register (35h) instruction.
- *
- * bit 1 of the Configuration Register is the QE bit for Spansion like QSPI
- * memories.
- *
- * Return: 0 on success, -errno otherwise.
- */
-static int spansion_read_cr_quad_enable(struct spi_nor *nor)
-{
- u8 *sr_cr = nor->bouncebuf;
- int ret;
- u8 sr_written;
+ if (nor->flags & SNOR_F_NO_READ_CR)
+ return spi_nor_write_16bit_cr_and_check(nor, SR2_QUAD_EN_BIT1);

- /* Check current Quad Enable bit value. */
- ret = spi_nor_read_cr(nor, &sr_cr[1]);
+ ret = spi_nor_read_cr(nor, &nor->bouncebuf[0]);
if (ret)
return ret;

- if (sr_cr[1] & SR2_QUAD_EN_BIT1)
+ if (nor->bouncebuf[0] & SR2_QUAD_EN_BIT1)
return 0;

- sr_cr[1] |= SR2_QUAD_EN_BIT1;
-
- /* Keep the current value of the Status Register. */
- ret = spi_nor_read_sr(nor, &sr_cr[0]);
- if (ret)
- return ret;
-
- ret = spi_nor_write_sr(nor, sr_cr, 2);
- if (ret)
- return ret;
-
- sr_written = sr_cr[0];
-
- ret = spi_nor_read_sr(nor, &sr_cr[0]);
- if (ret)
- return ret;
-
- if (sr_written != sr_cr[0]) {
- dev_err(nor->dev, "SR1: Read back test failed\n");
- return -EIO;
- }
-
- sr_written = sr_cr[1];
-
- /* Read back and check it. */
- ret = spi_nor_read_cr(nor, &sr_cr[1]);
- if (ret)
- return ret;
-
- if (sr_cr[1] != sr_written) {
- dev_err(nor->dev, "SR2: Read back test failed\n");
- return -EIO;
- }
-
- return 0;
+ return spi_nor_write_16bit_cr_and_check(nor, nor->bouncebuf[0]);
}

/**
@@ -2235,7 +2206,7 @@ static int spi_nor_clear_sr_bp(struct spi_nor *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_read_cr_quad_enable() function. Both assume that
+ * coupled with the spi_nor_sr2_bit1_quad_enable() function. Both assume that
* the Write Register with 16 bits, together with the Read Configuration
* Register (35h) instructions are supported.
*
@@ -3753,7 +3724,7 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
* supported.
*/
nor->flags |= SNOR_F_HAS_16BIT_SR | SNOR_F_NO_READ_CR;
- params->quad_enable = spansion_no_read_cr_quad_enable;
+ params->quad_enable = spi_nor_sr2_bit1_quad_enable;
break;

case BFPT_DWORD15_QER_SR1_BIT6:
@@ -3775,7 +3746,7 @@ static int spi_nor_parse_bfpt(struct spi_nor *nor,
*/
nor->flags |= SNOR_F_HAS_16BIT_SR;

- params->quad_enable = spansion_read_cr_quad_enable;
+ params->quad_enable = spi_nor_sr2_bit1_quad_enable;
break;

default:
@@ -4738,7 +4709,7 @@ static void spi_nor_info_init_params(struct spi_nor *nor)
u8 i, erase_mask;

/* Initialize legacy flash parameters and settings. */
- params->quad_enable = spansion_read_cr_quad_enable;
+ params->quad_enable = spi_nor_sr2_bit1_quad_enable;
params->set_4byte = spansion_set_4byte;
params->setup = spi_nor_default_setup;
/* Default to 16-bit Write Status (01h) Command */
@@ -4955,7 +4926,7 @@ static int spi_nor_init(struct spi_nor *nor)
int err;

if (nor->clear_sr_bp) {
- if (nor->params.quad_enable == spansion_read_cr_quad_enable)
+ if (nor->params.quad_enable == spi_nor_sr2_bit1_quad_enable)
nor->clear_sr_bp = spi_nor_spansion_clear_sr_bp;

err = nor->clear_sr_bp(nor);
--
2.9.5