[PATCH 4/6] spi: sun6i: use completion provided by SPI core

From: Sergey Suloev
Date: Fri Mar 30 2018 - 03:23:36 EST


As long as the completion is already provided by the SPI core
then there is no need to waste extra-memory on this.
Also a waiting function was added to avoid code duplication.

Signed-off-by: Sergey Suloev <ssuloev@xxxxxxxxxxxxx>

---
drivers/spi/spi-sun6i.c | 50 ++++++++++++++++++++++++++++---------------------
1 file changed, 29 insertions(+), 21 deletions(-)

diff --git a/drivers/spi/spi-sun6i.c b/drivers/spi/spi-sun6i.c
index 13396bd..fc43752 100644
--- a/drivers/spi/spi-sun6i.c
+++ b/drivers/spi/spi-sun6i.c
@@ -99,8 +99,6 @@ struct sun6i_spi {
struct clk *mclk;
struct reset_control *rstc;

- struct completion done;
-
const u8 *tx_buf;
u8 *rx_buf;
int len;
@@ -255,6 +253,30 @@ static int sun6i_spi_prepare_message(struct spi_master *master,
return 0;
}

+static int sun6i_spi_wait_for_transfer(struct spi_device *spi,
+ struct spi_transfer *tfr)
+{
+ struct spi_master *master = spi->master;
+ unsigned int start, end, tx_time;
+ unsigned int timeout;
+
+ /* smart wait for completion */
+ tx_time = max(tfr->len * 8 * 2 / (tfr->speed_hz / 1000), 100U);
+ start = jiffies;
+ timeout = wait_for_completion_timeout(&master->xfer_completion,
+ msecs_to_jiffies(tx_time));
+ end = jiffies;
+ if (!timeout) {
+ dev_warn(&master->dev,
+ "%s: timeout transferring %u bytes@%iHz for %i(%i)ms",
+ dev_name(&spi->dev), tfr->len, tfr->speed_hz,
+ jiffies_to_msecs(end - start), tx_time);
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
static int sun6i_spi_transfer_one(struct spi_master *master,
struct spi_device *spi,
struct spi_transfer *tfr)
@@ -275,7 +297,6 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
if (tfr->len > sspi->fifo_depth)
return -EMSGSIZE;

- reinit_completion(&sspi->done);
sspi->tx_buf = tfr->tx_buf;
sspi->rx_buf = tfr->rx_buf;
sspi->len = tfr->len;
@@ -342,21 +363,9 @@ static int sun6i_spi_transfer_one(struct spi_master *master,
reg = sun6i_spi_read(sspi, SUN6I_TFR_CTL_REG);
sun6i_spi_write(sspi, SUN6I_TFR_CTL_REG, reg | SUN6I_TFR_CTL_XCH);

- tx_time = max(tfr->len * 8 * 2 / (tfr->speed_hz / 1000), 100U);
- start = jiffies;
- timeout = wait_for_completion_timeout(&sspi->done,
- msecs_to_jiffies(tx_time));
- end = jiffies;
- if (!timeout) {
- dev_warn(&master->dev,
- "%s: timeout transferring %u bytes@%iHz for %i(%i)ms",
- dev_name(&spi->dev), tfr->len, tfr->speed_hz,
- jiffies_to_msecs(end - start), tx_time);
- ret = -ETIMEDOUT;
- goto out;
- }
+ /* Wait for completion */
+ ret = sun6i_spi_wait_for_transfer(spi, tfr);

-out:
sun6i_spi_write(sspi, SUN6I_INT_CTL_REG, 0);

return ret;
@@ -364,7 +373,8 @@ out:

static irqreturn_t sun6i_spi_handler(int irq, void *dev_id)
{
- struct sun6i_spi *sspi = dev_id;
+ struct spi_master *master = dev_id;
+ struct sun6i_spi *sspi = spi_master_get_devdata(master);
u32 status;

status = sun6i_spi_read(sspi, SUN6I_INT_STA_REG);
@@ -373,7 +383,7 @@ static irqreturn_t sun6i_spi_handler(int irq, void *dev_id)
if (status & SUN6I_INT_CTL_TC) {
sun6i_spi_write(sspi, SUN6I_INT_STA_REG, SUN6I_INT_CTL_TC);
sun6i_spi_drain_fifo(sspi, sspi->fifo_depth);
- complete(&sspi->done);
+ spi_finalize_current_transfer(master);
return IRQ_HANDLED;
}

@@ -494,8 +504,6 @@ static int sun6i_spi_probe(struct platform_device *pdev)
goto err_free_master;
}

- init_completion(&sspi->done);
-
sspi->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
if (IS_ERR(sspi->rstc)) {
dev_err(&pdev->dev, "Couldn't get reset controller\n");
--
2.16.2