[PATCH] spi: bcm-qspi: Remove hardcoded settings and spi-nor.h dependency

From: Kamal Dasu
Date: Wed Jul 26 2017 - 19:20:50 EST


The newly added broadcom qspi driver in drivers/spi produces a build
warning when CONFIG_MTD is disabled:
include/linux/mtd/cfi.h:76:2: #warning No CONFIG_MTD_CFI_Ix selected. No NOR chip support can work. [-Werror=cpp]

There has been discussion on this in the link provided below. This fix in
SPI controller drivers implementing the ->spi_flash_read handler, now uses the
settings provided inside the 'struct spi_flash_read_message' parameter instead
of hardcoding them. Made changes to bcm_qspi_bspi_set_flex_mode() to set the BSPI
controller using the passed msg structure and remove the need to include
<linux/mtd/spi-nor.h> file by removing all use of SPINOR_OP_READ* macros.

Fixes: 4e3b2d236fe0 ("spi: bcm-qspi: Add BSPI spi-nor flash controller driver")
Link: https://patchwork.kernel.org/patch/9624585/
Signed-off-by: Kamal Dasu <kdasu.kdev@xxxxxxxxx>
---
drivers/spi/spi-bcm-qspi.c | 89 +++++++++++++++++-----------------------------
1 file changed, 33 insertions(+), 56 deletions(-)

diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c
index b19722b..6ef6c44 100644
--- a/drivers/spi/spi-bcm-qspi.c
+++ b/drivers/spi/spi-bcm-qspi.c
@@ -25,7 +25,6 @@
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/module.h>
-#include <linux/mtd/spi-nor.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
@@ -349,76 +348,60 @@ static void bcm_qspi_bspi_set_xfer_params(struct bcm_qspi *qspi, u8 cmd_byte,
bcm_qspi_write(qspi, BSPI, BSPI_FLEX_MODE_ENABLE, flex_mode);
}

-static int bcm_qspi_bspi_set_flex_mode(struct bcm_qspi *qspi, int width,
- int addrlen, int hp)
+static int bcm_qspi_bspi_set_flex_mode(struct bcm_qspi *qspi,
+ struct spi_flash_read_message *msg,
+ int hp)
{
int bpc = 0, bpp = 0;
- u8 command = SPINOR_OP_READ_FAST;
- int flex_mode = 1, rv = 0;
- bool spans_4byte = false;
+ u8 command = msg->read_opcode;
+ int width = msg->data_nbits ? msg->data_nbits : SPI_NBITS_SINGLE;
+ int addrlen = msg->addr_width;
+ int addr_nbits = msg->addr_nbits ? msg->addr_nbits : SPI_NBITS_SINGLE;
+ int flex_mode = 1;

dev_dbg(&qspi->pdev->dev, "set flex mode w %x addrlen %x hp %d\n",
width, addrlen, hp);

- if (addrlen == BSPI_ADDRLEN_4BYTES) {
+ if (addrlen == BSPI_ADDRLEN_4BYTES)
bpp = BSPI_BPP_ADDR_SELECT_MASK;
- spans_4byte = true;
- }

- bpp |= 8;
+ bpp |= msg->dummy_bytes * (8/addr_nbits);

switch (width) {
case SPI_NBITS_SINGLE:
if (addrlen == BSPI_ADDRLEN_3BYTES)
/* default mode, does not need flex_cmd */
flex_mode = 0;
- else
- command = SPINOR_OP_READ_FAST_4B;
break;
case SPI_NBITS_DUAL:
bpc = 0x00000001;
if (hp) {
bpc |= 0x00010100; /* address and mode are 2-bit */
bpp = BSPI_BPP_MODE_SELECT_MASK;
- command = OPCODE_DIOR;
- if (spans_4byte)
- command = OPCODE_DIOR_4B;
- } else {
- command = SPINOR_OP_READ_1_1_2;
- if (spans_4byte)
- command = SPINOR_OP_READ_1_1_2_4B;
}
break;
case SPI_NBITS_QUAD:
bpc = 0x00000002;
if (hp) {
bpc |= 0x00020200; /* address and mode are 4-bit */
- bpp = 4; /* dummy cycles */
- bpp |= BSPI_BPP_ADDR_SELECT_MASK;
- command = OPCODE_QIOR;
- if (spans_4byte)
- command = OPCODE_QIOR_4B;
- } else {
- command = SPINOR_OP_READ_1_1_4;
- if (spans_4byte)
- command = SPINOR_OP_READ_1_1_4_4B;
+ bpp |= BSPI_BPP_MODE_SELECT_MASK;
}
break;
default:
- rv = -EINVAL;
- break;
+ return -EINVAL;
}

- if (rv == 0)
- bcm_qspi_bspi_set_xfer_params(qspi, command, bpp, bpc,
- flex_mode);
+ bcm_qspi_bspi_set_xfer_params(qspi, command, bpp, bpc, flex_mode);

- return rv;
+ return 0;
}

-static int bcm_qspi_bspi_set_override(struct bcm_qspi *qspi, int width,
- int addrlen, int hp)
+static int bcm_qspi_bspi_set_override(struct bcm_qspi *qspi,
+ struct spi_flash_read_message *msg,
+ int hp)
{
+ int width = msg->data_nbits ? msg->data_nbits : SPI_NBITS_SINGLE;
+ int addrlen = msg->addr_width;
u32 data = bcm_qspi_read(qspi, BSPI, BSPI_STRAP_OVERRIDE_CTRL);

dev_dbg(&qspi->pdev->dev, "set override mode w %x addrlen %x hp %d\n",
@@ -430,7 +413,6 @@ static int bcm_qspi_bspi_set_override(struct bcm_qspi *qspi, int width,
data &= ~(BSPI_STRAP_OVERRIDE_CTRL_DATA_QUAD |
BSPI_STRAP_OVERRIDE_CTRL_DATA_DUAL);
break;
-
case SPI_NBITS_QUAD:
/* clear dual mode and set quad mode */
data &= ~BSPI_STRAP_OVERRIDE_CTRL_DATA_DUAL;
@@ -455,15 +437,17 @@ static int bcm_qspi_bspi_set_override(struct bcm_qspi *qspi, int width,
/* set the override mode */
data |= BSPI_STRAP_OVERRIDE_CTRL_OVERRIDE;
bcm_qspi_write(qspi, BSPI, BSPI_STRAP_OVERRIDE_CTRL, data);
- bcm_qspi_bspi_set_xfer_params(qspi, SPINOR_OP_READ_FAST, 0, 0, 0);
+ bcm_qspi_bspi_set_xfer_params(qspi, msg->read_opcode, 0, 0, 0);

return 0;
}

static int bcm_qspi_bspi_set_mode(struct bcm_qspi *qspi,
- int width, int addrlen, int hp)
+ struct spi_flash_read_message *msg, int hp)
{
int error = 0;
+ int width = msg->data_nbits ? msg->data_nbits : SPI_NBITS_SINGLE;
+ int addrlen = msg->addr_width;

/* default mode */
qspi->xfer_mode.flex_mode = true;
@@ -475,23 +459,13 @@ static int bcm_qspi_bspi_set_mode(struct bcm_qspi *qspi,
mask = BSPI_STRAP_OVERRIDE_CTRL_OVERRIDE;
if (val & mask || qspi->s3_strap_override_ctrl & mask) {
qspi->xfer_mode.flex_mode = false;
- bcm_qspi_write(qspi, BSPI, BSPI_FLEX_MODE_ENABLE,
- 0);
-
- if ((val | qspi->s3_strap_override_ctrl) &
- BSPI_STRAP_OVERRIDE_CTRL_DATA_DUAL)
- width = SPI_NBITS_DUAL;
- else if ((val | qspi->s3_strap_override_ctrl) &
- BSPI_STRAP_OVERRIDE_CTRL_DATA_QUAD)
- width = SPI_NBITS_QUAD;
-
- error = bcm_qspi_bspi_set_override(qspi, width, addrlen,
- hp);
+ bcm_qspi_write(qspi, BSPI, BSPI_FLEX_MODE_ENABLE, 0);
+ error = bcm_qspi_bspi_set_override(qspi, msg, hp);
}
}

if (qspi->xfer_mode.flex_mode)
- error = bcm_qspi_bspi_set_flex_mode(qspi, width, addrlen, hp);
+ error = bcm_qspi_bspi_set_flex_mode(qspi, msg, hp);

if (error) {
dev_warn(&qspi->pdev->dev,
@@ -981,7 +955,7 @@ static int bcm_qspi_flash_read(struct spi_device *spi,
struct bcm_qspi *qspi = spi_master_get_devdata(spi->master);
int ret = 0;
bool mspi_read = false;
- u32 io_width, addrlen, addr, len;
+ u32 addr, len;
u_char *buf;

buf = msg->buf;
@@ -1010,9 +984,7 @@ static int bcm_qspi_flash_read(struct spi_device *spi,
if (mspi_read)
return bcm_qspi_mspi_flash_read(spi, msg);

- io_width = msg->data_nbits ? msg->data_nbits : SPI_NBITS_SINGLE;
- addrlen = msg->addr_width;
- ret = bcm_qspi_bspi_set_mode(qspi, io_width, addrlen, -1);
+ ret = bcm_qspi_bspi_set_mode(qspi, msg, -1);

if (!ret)
ret = bcm_qspi_bspi_flash_read(spi, msg);
@@ -1422,6 +1394,11 @@ static int __maybe_unused bcm_qspi_suspend(struct device *dev)
{
struct bcm_qspi *qspi = dev_get_drvdata(dev);

+ /* store the override strap value */
+ if (!bcm_qspi_bspi_ver_three(qspi))
+ qspi->s3_strap_override_ctrl =
+ bcm_qspi_read(qspi, BSPI, BSPI_STRAP_OVERRIDE_CTRL);
+
spi_master_suspend(qspi->master);
clk_disable(qspi->clk);
bcm_qspi_hw_uninit(qspi);
--
1.9.0.138.g2de3478