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Subject[PATCH v2 6/6] spi: sh-msiof: Use core message handling instead of spi-bitbang
Date
From: Geert Uytterhoeven <geert+renesas@linux-m68k.org>

The only remaining feature of spi-bitbang used by this driver is the
chipselect() callback, which just does conditional GPIO.
This is handled fine by the SPI core's spi_set_cs(), hence switch the
driver to use the core message handling through our own transfer_one()
method.

As the (optional) GPIO CS is no longer deasserted at spi_master.setup()
time (through spi_bitbang_setup() and the spi_bitbang.chipselect()
callback), we now have to take care of that ourselves.

Remove the call to spi_master_put() in sh_msiof_spi_remove(), as our SPI
master is now registered using devm_spi_register_master()
(spi_bitbang_start() uses the non-managed version).

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
---
v2:
- Deassert (optional) GPIO CS in sh_msiof_spi_setup()

drivers/spi/Kconfig | 1 -
drivers/spi/spi-sh-msiof.c | 67 +++++++++++++-------------------------------
2 files changed, 20 insertions(+), 48 deletions(-)

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 64d8cac0f326..17df2069fca2 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -429,7 +429,6 @@ config SPI_SH_MSIOF
tristate "SuperH MSIOF SPI controller"
depends on HAVE_CLK
depends on SUPERH || ARCH_SHMOBILE || COMPILE_TEST
- select SPI_BITBANG
help
SPI driver for SuperH and SH Mobile MSIOF blocks.

diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c
index 27536933d734..55a8c2aa1f04 100644
--- a/drivers/spi/spi-sh-msiof.c
+++ b/drivers/spi/spi-sh-msiof.c
@@ -26,7 +26,6 @@

#include <linux/spi/sh_msiof.h>
#include <linux/spi/spi.h>
-#include <linux/spi/spi_bitbang.h>

#include <asm/unaligned.h>

@@ -38,7 +37,6 @@ struct sh_msiof_chipdata {
};

struct sh_msiof_spi_priv {
- struct spi_bitbang bitbang; /* must be first for spi_bitbang.c */
void __iomem *mapbase;
struct clk *clk;
struct platform_device *pdev;
@@ -458,7 +456,10 @@ static int sh_msiof_spi_setup(struct spi_device *spi)
!!(spi->mode & SPI_LSB_FIRST),
!!(spi->mode & SPI_CS_HIGH));

- return spi_bitbang_setup(spi);
+ if (spi->cs_gpio >= 0)
+ gpio_set_value(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
+
+ return 0;
}

static int sh_msiof_prepare_message(struct spi_master *master,
@@ -489,20 +490,6 @@ static int sh_msiof_unprepare_message(struct spi_master *master,
return 0;
}

-static void sh_msiof_spi_chipselect(struct spi_device *spi, int is_on)
-{
- int value;
-
- /* chip select is active low unless SPI_CS_HIGH is set */
- if (spi->mode & SPI_CS_HIGH)
- value = (is_on == BITBANG_CS_ACTIVE) ? 1 : 0;
- else
- value = (is_on == BITBANG_CS_ACTIVE) ? 0 : 1;
-
- if (spi->cs_gpio >= 0)
- gpio_set_value(spi->cs_gpio, value);
-}
-
static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
void (*tx_fifo)(struct sh_msiof_spi_priv *,
const void *, int, int),
@@ -572,9 +559,11 @@ static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
return ret;
}

-static int sh_msiof_spi_txrx(struct spi_device *spi, struct spi_transfer *t)
+static int sh_msiof_transfer_one(struct spi_master *master,
+ struct spi_device *spi,
+ struct spi_transfer *t)
{
- struct sh_msiof_spi_priv *p = spi_master_get_devdata(spi->master);
+ struct sh_msiof_spi_priv *p = spi_master_get_devdata(master);
void (*tx_fifo)(struct sh_msiof_spi_priv *, const void *, int, int);
void (*rx_fifo)(struct sh_msiof_spi_priv *, void *, int, int);
int bits;
@@ -655,13 +644,6 @@ static int sh_msiof_spi_txrx(struct spi_device *spi, struct spi_transfer *t)
words -= n;
}

- return bytes_done;
-}
-
-static u32 sh_msiof_spi_txrx_word(struct spi_device *spi, unsigned nsecs,
- u32 word, u8 bits)
-{
- BUG(); /* unused but needed by bitbang code */
return 0;
}

@@ -798,7 +780,7 @@ static int sh_msiof_spi_probe(struct platform_device *pdev)
if (p->info->rx_fifo_override)
p->rx_fifo_size = p->info->rx_fifo_override;

- /* init master and bitbang code */
+ /* init master code */
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
master->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE;
master->flags = p->chipdata->master_flags;
@@ -806,24 +788,20 @@ static int sh_msiof_spi_probe(struct platform_device *pdev)
master->dev.of_node = pdev->dev.of_node;
master->num_chipselect = p->info->num_chipselect;
master->setup = sh_msiof_spi_setup;
- master->cleanup = spi_bitbang_cleanup;
master->prepare_message = sh_msiof_prepare_message;
master->unprepare_message = sh_msiof_unprepare_message;
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32);
+ master->transfer_one = sh_msiof_transfer_one;

- p->bitbang.master = master;
- p->bitbang.chipselect = sh_msiof_spi_chipselect;
- p->bitbang.setup_transfer = spi_bitbang_setup_transfer;
- p->bitbang.txrx_bufs = sh_msiof_spi_txrx;
- p->bitbang.txrx_word[SPI_MODE_0] = sh_msiof_spi_txrx_word;
- p->bitbang.txrx_word[SPI_MODE_1] = sh_msiof_spi_txrx_word;
- p->bitbang.txrx_word[SPI_MODE_2] = sh_msiof_spi_txrx_word;
- p->bitbang.txrx_word[SPI_MODE_3] = sh_msiof_spi_txrx_word;
+ ret = devm_spi_register_master(&pdev->dev, master);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "spi_register_master error.\n");
+ goto err2;
+ }

- ret = spi_bitbang_start(&p->bitbang);
- if (ret == 0)
- return 0;
+ return 0;

+ err2:
pm_runtime_disable(&pdev->dev);
clk_unprepare(p->clk);
err1:
@@ -834,15 +812,10 @@ static int sh_msiof_spi_probe(struct platform_device *pdev)
static int sh_msiof_spi_remove(struct platform_device *pdev)
{
struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev);
- int ret;

- ret = spi_bitbang_stop(&p->bitbang);
- if (!ret) {
- pm_runtime_disable(&pdev->dev);
- clk_unprepare(p->clk);
- spi_master_put(p->bitbang.master);
- }
- return ret;
+ pm_runtime_disable(&pdev->dev);
+ clk_unprepare(p->clk);
+ return 0;
}

static struct platform_device_id spi_driver_ids[] = {
--
1.7.9.5


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