[PATCH 7/7] spi: spi-fsl-dspi: Add support for TCFQ transfer mode
Bhuvanchandra DV
bhuvanchandra.dv at toradex.com
Tue Jan 27 03:03:28 PST 2015
From: Chao Fu <B44548 at freescale.com>
TCFQ is interrupt of Transfer Complete Flag in DSPI module.
EOQ is interrupt of End of Queue Flag in DSPI module.
For adopting of different platform, either of them is a way of DSPI
transfer data. This patch add TCF support for DSPI module in other platform.
Signed-off-by: Bhuvanchandra DV <bhuvanchandra.dv at toradex.com>
---
.../devicetree/bindings/spi/spi-fsl-dspi.txt | 2 +
drivers/spi/spi-fsl-dspi.c | 74 +++++++++++++++++++---
2 files changed, 68 insertions(+), 8 deletions(-)
diff --git a/Documentation/devicetree/bindings/spi/spi-fsl-dspi.txt b/Documentation/devicetree/bindings/spi/spi-fsl-dspi.txt
index cbbe16e..b50439f 100644
--- a/Documentation/devicetree/bindings/spi/spi-fsl-dspi.txt
+++ b/Documentation/devicetree/bindings/spi/spi-fsl-dspi.txt
@@ -15,6 +15,8 @@ Optional property:
- big-endian: If present the dspi device's registers are implemented
in big endian mode, otherwise in native mode(same with CPU), for more
detail please see: Documentation/devicetree/bindings/regmap/regmap.txt.
+- tcfq-mode: If present, the data transfer will be done at TCFQ interrupt.
+ By default, driver chooses EOQ interrupt if 'tcfq-mode' property was not set.
Example:
diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c
index e0ce906..feca2fd 100644
--- a/drivers/spi/spi-fsl-dspi.c
+++ b/drivers/spi/spi-fsl-dspi.c
@@ -63,9 +63,11 @@
#define SPI_CTAR0_SLAVE 0x0c
#define SPI_SR 0x2c
+#define SPI_SR_TCFQF 0x80000000
#define SPI_SR_EOQF 0x10000000
#define SPI_RSER 0x30
+#define SPI_RSER_TCFQE 0x80000000
#define SPI_RSER_EOQFE 0x10000000
#define SPI_PUSHR 0x34
@@ -105,6 +107,12 @@ struct chip_data {
u16 void_write_data;
};
+enum dspi_trans_mode {
+ DSPI_EOQ_MODE = 0,
+ DSPI_TCFQ_MODE,
+ DSPI_DMA_MODE, /*TODO*/
+};
+
struct fsl_dspi {
struct spi_master *master;
struct platform_device *pdev;
@@ -125,6 +133,7 @@ struct fsl_dspi {
u8 cs;
u16 void_write_data;
u32 cs_change;
+ enum dspi_trans_mode trans_mode;
wait_queue_head_t waitq;
u32 waitflags;
@@ -225,7 +234,7 @@ static void dspi_data_from_popr(struct fsl_dspi *dspi, int rx_word)
}
}
-static int dspi_transfer_write(struct fsl_dspi *dspi)
+static int dspi_eoq_write(struct fsl_dspi *dspi)
{
int tx_count = 0;
int tx_word;
@@ -269,7 +278,7 @@ static int dspi_transfer_write(struct fsl_dspi *dspi)
return tx_count * (tx_word + 1);
}
-static int dspi_transfer_read(struct fsl_dspi *dspi)
+static int dspi_eoq_read(struct fsl_dspi *dspi)
{
int rx_count = 0;
int rx_word = is_double_byte_mode(dspi);
@@ -283,6 +292,37 @@ static int dspi_transfer_read(struct fsl_dspi *dspi)
return rx_count;
}
+static int dspi_tcfq_write(struct fsl_dspi *dspi)
+{
+ int tx_word;
+ u32 dspi_pushr = 0;
+
+ tx_word = is_double_byte_mode(dspi);
+
+ if (tx_word && (dspi->len == 1)) {
+ dspi->dataflags |= TRAN_STATE_WORD_ODD_NUM;
+ regmap_update_bits(dspi->regmap, SPI_CTAR(dspi->cs),
+ SPI_FRAME_BITS_MASK, SPI_FRAME_BITS(8));
+ tx_word = 0;
+ }
+
+ dspi_pushr = dspi_data_to_pushr(dspi, tx_word);
+
+ if ((dspi->cs_change) && (!dspi->len))
+ dspi_pushr &= ~SPI_PUSHR_CONT;
+
+ regmap_write(dspi->regmap, SPI_PUSHR, dspi_pushr);
+
+ return tx_word + 1;
+}
+
+static void dspi_tcfq_read(struct fsl_dspi *dspi)
+{
+ int rx_word = is_double_byte_mode(dspi);
+
+ dspi_data_from_popr(dspi, rx_word);
+}
+
static int dspi_transfer_one_message(struct spi_master *master,
struct spi_message *message)
{
@@ -326,8 +366,13 @@ static int dspi_transfer_one_message(struct spi_master *master,
regmap_write(dspi->regmap, SPI_CTAR(dspi->cs),
dspi->cur_chip->ctar_val);
- regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_EOQFE);
- message->actual_length += dspi_transfer_write(dspi);
+ if (dspi->trans_mode == DSPI_EOQ_MODE) {
+ regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_EOQFE);
+ message->actual_length += dspi_eoq_write(dspi);
+ } else if (dspi->trans_mode == DSPI_TCFQ_MODE) {
+ regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_TCFQE);
+ message->actual_length += dspi_tcfq_write(dspi);
+ }
if (wait_event_interruptible(dspi->waitq, dspi->waitflags))
dev_err(&dspi->pdev->dev, "wait transfer complete fail!\n");
@@ -399,8 +444,13 @@ static irqreturn_t dspi_interrupt(int irq, void *dev_id)
struct spi_message *msg = dspi->cur_msg;
- regmap_write(dspi->regmap, SPI_SR, SPI_SR_EOQF);
- dspi_transfer_read(dspi);
+ if (dspi->trans_mode == DSPI_EOQ_MODE) {
+ regmap_write(dspi->regmap, SPI_SR, SPI_SR_EOQF);
+ dspi_eoq_read(dspi);
+ } else if (dspi->trans_mode == DSPI_TCFQ_MODE) {
+ regmap_write(dspi->regmap, SPI_SR, SPI_SR_TCFQF);
+ dspi_tcfq_read(dspi);
+ }
if (!dspi->len) {
if (dspi->dataflags & TRAN_STATE_WORD_ODD_NUM)
@@ -409,8 +459,12 @@ static irqreturn_t dspi_interrupt(int irq, void *dev_id)
dspi->waitflags = 1;
wake_up_interruptible(&dspi->waitq);
- } else
- msg->actual_length += dspi_transfer_write(dspi);
+ } else {
+ if (dspi->trans_mode == DSPI_EOQ_MODE)
+ msg->actual_length += dspi_eoq_write(dspi);
+ else if (dspi->trans_mode == DSPI_TCFQ_MODE)
+ msg->actual_length += dspi_tcfq_write(dspi);
+ }
return IRQ_HANDLED;
}
@@ -470,6 +524,7 @@ static int dspi_probe(struct platform_device *pdev)
dspi = spi_master_get_devdata(master);
dspi->pdev = pdev;
dspi->master = master;
+ dspi->trans_mode = DSPI_EOQ_MODE;
master->transfer = NULL;
master->setup = dspi_setup;
@@ -481,6 +536,9 @@ static int dspi_probe(struct platform_device *pdev)
master->bits_per_word_mask = SPI_BPW_MASK(4) | SPI_BPW_MASK(8) |
SPI_BPW_MASK(16);
+ if (of_property_read_bool(np, "tcfq-mode"))
+ dspi->trans_mode = DSPI_TCFQ_MODE;
+
ret = of_property_read_u32(np, "spi-num-chipselects", &cs_num);
if (ret < 0) {
dev_err(&pdev->dev, "can't get spi-num-chipselects\n");
--
2.2.2
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