[PATCH 7/7] spi: spi-fsl-dspi: Add support for TCFQ transfer mode
From: Bhuvanchandra DV <hidden>
Date: 2015-01-27 10:58:37
Also in:
linux-arm-kernel, linux-spi, lkml
Subsystem:
freescale dspi driver, open firmware and flattened device tree bindings, spi subsystem, the rest · Maintainers:
Vladimir Oltean, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Mark Brown, Linus Torvalds
From: Chao Fu <redacted> 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 <redacted> --- .../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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