[PATCH 5/7] spi: spi-fsl-dspi: Remove spi-bitbang

From: Bhuvanchandra DV
Date: Tue Jan 27 2015 - 05:54:40 EST


From: Chao Fu <B44548@xxxxxxxxxxxxx>

DSPI module need cs change information in
a spi transfer. According to cs change, DSPI
will give last data the right flag. Bitbang
provide cs change behind the last data in
a transfer. So DSPI can not deal the last
data in every transfer properly, so remove
the bitbang in the driver.

Signed-off-by: Bhuvanchandra DV <bhuvanchandra.dv@xxxxxxxxxxx>
---
drivers/spi/Kconfig | 1 -
drivers/spi/spi-fsl-dspi.c | 144 ++++++++++++++++++++++-----------------------
2 files changed, 71 insertions(+), 74 deletions(-)

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 9982998..6316d6d 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -292,7 +292,6 @@ config SPI_FSL_SPI

config SPI_FSL_DSPI
tristate "Freescale DSPI controller"
- select SPI_BITBANG
select REGMAP_MMIO
depends on SOC_VF610 || COMPILE_TEST
help
diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c
index 5378148..b20dbb5 100644
--- a/drivers/spi/spi-fsl-dspi.c
+++ b/drivers/spi/spi-fsl-dspi.c
@@ -106,7 +106,7 @@ struct chip_data {
};

struct fsl_dspi {
- struct spi_bitbang bitbang;
+ struct spi_master *master;
struct platform_device *pdev;

struct regmap *regmap;
@@ -114,6 +114,7 @@ struct fsl_dspi {
struct clk *clk;

struct spi_transfer *cur_transfer;
+ struct spi_message *cur_msg;
struct chip_data *cur_chip;
size_t len;
void *tx;
@@ -123,6 +124,7 @@ struct fsl_dspi {
char dataflags;
u8 cs;
u16 void_write_data;
+ u32 cs_change;

wait_queue_head_t waitq;
u32 waitflags;
@@ -225,6 +227,8 @@ static int dspi_transfer_write(struct fsl_dspi *dspi)
if (dspi->len == 0 || tx_count == DSPI_FIFO_SIZE - 1) {
/* last transfer in the transfer */
dspi_pushr |= SPI_PUSHR_EOQ;
+ if ((dspi->cs_change) && (!dspi->len))
+ dspi_pushr &= ~SPI_PUSHR_CONT;
} else if (tx_word && (dspi->len == 1))
dspi_pushr |= SPI_PUSHR_EOQ;

@@ -246,6 +250,7 @@ static int dspi_transfer_read(struct fsl_dspi *dspi)
int rx_count = 0;
int rx_word = is_double_byte_mode(dspi);
u16 d;
+
while ((dspi->rx < dspi->rx_end)
&& (rx_count < DSPI_FIFO_SIZE)) {
if (rx_word) {
@@ -276,64 +281,67 @@ static int dspi_transfer_read(struct fsl_dspi *dspi)
return rx_count;
}

-static int dspi_txrx_transfer(struct spi_device *spi, struct spi_transfer *t)
+static int dspi_transfer_one_message(struct spi_master *master,
+ struct spi_message *message)
{
- struct fsl_dspi *dspi = spi_master_get_devdata(spi->master);
- dspi->cur_transfer = t;
- dspi->cur_chip = spi_get_ctldata(spi);
- dspi->cs = spi->chip_select;
- dspi->void_write_data = dspi->cur_chip->void_write_data;
-
- dspi->dataflags = 0;
- dspi->tx = (void *)t->tx_buf;
- dspi->tx_end = dspi->tx + t->len;
- dspi->rx = t->rx_buf;
- dspi->rx_end = dspi->rx + t->len;
- dspi->len = t->len;
-
- if (!dspi->rx)
- dspi->dataflags |= TRAN_STATE_RX_VOID;
-
- if (!dspi->tx)
- dspi->dataflags |= TRAN_STATE_TX_VOID;
-
- regmap_write(dspi->regmap, SPI_MCR, dspi->cur_chip->mcr_val);
- regmap_write(dspi->regmap, SPI_CTAR(dspi->cs), dspi->cur_chip->ctar_val);
- regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_EOQFE);
-
- if (t->speed_hz)
+ struct fsl_dspi *dspi = spi_master_get_devdata(master);
+ struct spi_device *spi = message->spi;
+ struct spi_transfer *transfer;
+ int status = 0;
+ message->actual_length = 0;
+
+ list_for_each_entry(transfer, &message->transfers, transfer_list) {
+ dspi->cur_transfer = transfer;
+ dspi->cur_msg = message;
+ dspi->cur_chip = spi_get_ctldata(spi);
+ dspi->cs = spi->chip_select;
+ if (dspi->cur_transfer->transfer_list.next
+ == &dspi->cur_msg->transfers)
+ transfer->cs_change = 1;
+ dspi->cs_change = transfer->cs_change;
+ dspi->void_write_data = dspi->cur_chip->void_write_data;
+
+ dspi->dataflags = 0;
+ dspi->tx = (void *)transfer->tx_buf;
+ dspi->tx_end = dspi->tx + transfer->len;
+ dspi->rx = transfer->rx_buf;
+ dspi->rx_end = dspi->rx + transfer->len;
+ dspi->len = transfer->len;
+
+ if (!dspi->rx)
+ dspi->dataflags |= TRAN_STATE_RX_VOID;
+
+ if (!dspi->tx)
+ dspi->dataflags |= TRAN_STATE_TX_VOID;
+
+ regmap_write(dspi->regmap, SPI_MCR, dspi->cur_chip->mcr_val);
+ regmap_update_bits(dspi->regmap, SPI_MCR,
+ SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
+ SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
regmap_write(dspi->regmap, SPI_CTAR(dspi->cs),
dspi->cur_chip->ctar_val);
+ if (transfer->speed_hz)
+ regmap_write(dspi->regmap, SPI_CTAR(dspi->cs),
+ dspi->cur_chip->ctar_val);

- dspi_transfer_write(dspi);
-
- if (wait_event_interruptible(dspi->waitq, dspi->waitflags))
- dev_err(&dspi->pdev->dev, "wait transfer complete fail!\n");
- dspi->waitflags = 0;
-
- return t->len - dspi->len;
-}
-
-static void dspi_chipselect(struct spi_device *spi, int value)
-{
- struct fsl_dspi *dspi = spi_master_get_devdata(spi->master);
- unsigned int pushr;
+ regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_EOQFE);
+ message->actual_length += dspi_transfer_write(dspi);

- regmap_read(dspi->regmap, SPI_PUSHR, &pushr);
+ if (wait_event_interruptible(dspi->waitq, dspi->waitflags))
+ dev_err(&dspi->pdev->dev, "wait transfer complete fail!\n");
+ dspi->waitflags = 0;

- switch (value) {
- case BITBANG_CS_ACTIVE:
- pushr |= SPI_PUSHR_CONT;
- break;
- case BITBANG_CS_INACTIVE:
- pushr &= ~SPI_PUSHR_CONT;
- break;
+ if (transfer->delay_usecs)
+ udelay(transfer->delay_usecs);
}

- regmap_write(dspi->regmap, SPI_PUSHR, pushr);
+ message->status = status;
+ spi_finalize_current_message(master);
+
+ return status;
}

-static int dspi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
+static int dspi_setup(struct spi_device *spi)
{
struct chip_data *chip;
struct fsl_dspi *dspi = spi_master_get_devdata(spi->master);
@@ -373,14 +381,6 @@ static int dspi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
return 0;
}

-static int dspi_setup(struct spi_device *spi)
-{
- if (!spi->max_speed_hz)
- return -EINVAL;
-
- return dspi_setup_transfer(spi, NULL);
-}
-
static void dspi_cleanup(struct spi_device *spi)
{
struct chip_data *chip = spi_get_ctldata((struct spi_device *)spi);
@@ -395,22 +395,20 @@ static irqreturn_t dspi_interrupt(int irq, void *dev_id)
{
struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id;

- regmap_write(dspi->regmap, SPI_SR, SPI_SR_EOQF);
+ struct spi_message *msg = dspi->cur_msg;

+ regmap_write(dspi->regmap, SPI_SR, SPI_SR_EOQF);
dspi_transfer_read(dspi);

if (!dspi->len) {
if (dspi->dataflags & TRAN_STATE_WORD_ODD_NUM)
regmap_update_bits(dspi->regmap, SPI_CTAR(dspi->cs),
- SPI_FRAME_BITS_MASK, SPI_FRAME_BITS(16));
+ SPI_FRAME_BITS_MASK, SPI_FRAME_BITS(16));

dspi->waitflags = 1;
wake_up_interruptible(&dspi->waitq);
- } else {
- dspi_transfer_write(dspi);
-
- return IRQ_HANDLED;
- }
+ } else
+ msg->actual_length += dspi_transfer_write(dspi);

return IRQ_HANDLED;
}
@@ -469,12 +467,12 @@ static int dspi_probe(struct platform_device *pdev)

dspi = spi_master_get_devdata(master);
dspi->pdev = pdev;
- dspi->bitbang.master = master;
- dspi->bitbang.chipselect = dspi_chipselect;
- dspi->bitbang.setup_transfer = dspi_setup_transfer;
- dspi->bitbang.txrx_bufs = dspi_txrx_transfer;
- dspi->bitbang.master->setup = dspi_setup;
- dspi->bitbang.master->dev.of_node = pdev->dev.of_node;
+ dspi->master = master;
+
+ master->transfer = NULL;
+ master->setup = dspi_setup;
+ master->transfer_one_message = dspi_transfer_one_message;
+ master->dev.of_node = pdev->dev.of_node;

master->cleanup = dspi_cleanup;
master->mode_bits = SPI_CPOL | SPI_CPHA;
@@ -535,7 +533,7 @@ static int dspi_probe(struct platform_device *pdev)
init_waitqueue_head(&dspi->waitq);
platform_set_drvdata(pdev, master);

- ret = spi_bitbang_start(&dspi->bitbang);
+ ret = spi_register_master(master);
if (ret != 0) {
dev_err(&pdev->dev, "Problem registering DSPI master\n");
goto out_clk_put;
@@ -557,9 +555,9 @@ static int dspi_remove(struct platform_device *pdev)
struct fsl_dspi *dspi = spi_master_get_devdata(master);

/* Disconnect from the SPI framework */
- spi_bitbang_stop(&dspi->bitbang);
clk_disable_unprepare(dspi->clk);
- spi_master_put(dspi->bitbang.master);
+ spi_unregister_master(dspi->master);
+ spi_master_put(dspi->master);

return 0;
}
--
2.2.2

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