[PATCH v6 08/14] spi: qup: refactor spi_qup_io_config into two functions

From: Varadarajan Narayanan
Date: Fri Jul 28 2017 - 02:53:55 EST


This is in preparation for handling transactions larger than
64K-1 bytes in block mode, which is currently unsupported and
quietly fails.

We need to break these into two functions 1) prep is
called once per spi_message and 2) io_config is called
once per spi-qup bus transaction

This is just refactoring, there should be no functional
change

Signed-off-by: Matthew McClintock <mmcclint@xxxxxxxxxxxxxx>
Signed-off-by: Varadarajan Narayanan <varada@xxxxxxxxxxxxxx>
---
drivers/spi/spi-qup.c | 91 +++++++++++++++++++++++++++++++++++----------------
1 file changed, 62 insertions(+), 29 deletions(-)

diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c
index 8cfa112..ff5aa08 100644
--- a/drivers/spi/spi-qup.c
+++ b/drivers/spi/spi-qup.c
@@ -545,12 +545,11 @@ static irqreturn_t spi_qup_qup_irq(int irq, void *dev_id)
return IRQ_HANDLED;
}

-/* set clock freq ... bits per word */
-static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer)
+/* set clock freq ... bits per word, determine mode */
+static int spi_qup_io_prep(struct spi_device *spi, struct spi_transfer *xfer)
{
struct spi_qup *controller = spi_master_get_devdata(spi->master);
- u32 config, iomode, control;
- int ret, n_words;
+ int ret;

if (spi->mode & SPI_LOOP && xfer->len > controller->in_fifo_sz) {
dev_err(controller->dev, "too big size for loopback %d > %d\n",
@@ -565,32 +564,56 @@ static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer)
return -EIO;
}

- if (spi_qup_set_state(controller, QUP_STATE_RESET)) {
- dev_err(controller->dev, "cannot set RESET state\n");
- return -EIO;
- }
-
controller->w_size = DIV_ROUND_UP(xfer->bits_per_word, 8);
controller->n_words = xfer->len / controller->w_size;
- n_words = controller->n_words;
-
- if (n_words <= (controller->in_fifo_sz / sizeof(u32))) {

+ if (controller->n_words <= (controller->in_fifo_sz / sizeof(u32)))
controller->mode = QUP_IO_M_MODE_FIFO;
+ else if (spi->master->can_dma &&
+ spi->master->can_dma(spi->master, spi, xfer) &&
+ spi->master->cur_msg_mapped)
+ controller->mode = QUP_IO_M_MODE_BAM;
+ else
+ controller->mode = QUP_IO_M_MODE_BLOCK;
+
+ return 0;
+}
+
+/* prep qup for another spi transaction of specific type */
+static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer)
+{
+ struct spi_qup *controller = spi_master_get_devdata(spi->master);
+ u32 config, iomode, control;
+ unsigned long flags;
+
+ spin_lock_irqsave(&controller->lock, flags);
+ controller->xfer = xfer;
+ controller->error = 0;
+ controller->rx_bytes = 0;
+ controller->tx_bytes = 0;
+ spin_unlock_irqrestore(&controller->lock, flags);
+
+
+ if (spi_qup_set_state(controller, QUP_STATE_RESET)) {
+ dev_err(controller->dev, "cannot set RESET state\n");
+ return -EIO;
+ }

- writel_relaxed(n_words, controller->base + QUP_MX_READ_CNT);
- writel_relaxed(n_words, controller->base + QUP_MX_WRITE_CNT);
+ switch (controller->mode) {
+ case QUP_IO_M_MODE_FIFO:
+ writel_relaxed(controller->n_words,
+ controller->base + QUP_MX_READ_CNT);
+ writel_relaxed(controller->n_words,
+ controller->base + QUP_MX_WRITE_CNT);
/* must be zero for FIFO */
writel_relaxed(0, controller->base + QUP_MX_INPUT_CNT);
writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT);
- } else if (spi->master->can_dma &&
- spi->master->can_dma(spi->master, spi, xfer) &&
- spi->master->cur_msg_mapped) {
-
- controller->mode = QUP_IO_M_MODE_BAM;
-
- writel_relaxed(n_words, controller->base + QUP_MX_INPUT_CNT);
- writel_relaxed(n_words, controller->base + QUP_MX_OUTPUT_CNT);
+ break;
+ case QUP_IO_M_MODE_BAM:
+ writel_relaxed(controller->n_words,
+ controller->base + QUP_MX_INPUT_CNT);
+ writel_relaxed(controller->n_words,
+ controller->base + QUP_MX_OUTPUT_CNT);
/* must be zero for BLOCK and BAM */
writel_relaxed(0, controller->base + QUP_MX_READ_CNT);
writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT);
@@ -608,19 +631,25 @@ static int spi_qup_io_config(struct spi_device *spi, struct spi_transfer *xfer)
if (xfer->tx_buf)
writel_relaxed(0, input_cnt);
else
- writel_relaxed(n_words, input_cnt);
+ writel_relaxed(controller->n_words, input_cnt);

writel_relaxed(0, controller->base + QUP_MX_OUTPUT_CNT);
}
- } else {
-
- controller->mode = QUP_IO_M_MODE_BLOCK;
-
- writel_relaxed(n_words, controller->base + QUP_MX_INPUT_CNT);
- writel_relaxed(n_words, controller->base + QUP_MX_OUTPUT_CNT);
+ break;
+ case QUP_IO_M_MODE_BLOCK:
+ reinit_completion(&controller->done);
+ writel_relaxed(controller->n_words,
+ controller->base + QUP_MX_INPUT_CNT);
+ writel_relaxed(controller->n_words,
+ controller->base + QUP_MX_OUTPUT_CNT);
/* must be zero for BLOCK and BAM */
writel_relaxed(0, controller->base + QUP_MX_READ_CNT);
writel_relaxed(0, controller->base + QUP_MX_WRITE_CNT);
+ break;
+ default:
+ dev_err(controller->dev, "unknown mode = %d\n",
+ controller->mode);
+ return -EIO;
}

iomode = readl_relaxed(controller->base + QUP_IO_M_MODES);
@@ -709,6 +738,10 @@ static int spi_qup_transfer_one(struct spi_master *master,
unsigned long timeout, flags;
int ret = -EIO;

+ ret = spi_qup_io_prep(spi, xfer);
+ if (ret)
+ return ret;
+
ret = spi_qup_io_config(spi, xfer);
if (ret)
return ret;
--
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