[PATCH] spi: rockchip: disable spi on error

From: Emil Renner Berthing
Date: Wed Oct 31 2018 - 06:57:02 EST


Successful transfers leave the spi disabled, so if
we just make sure to disable the spi on error
there should be no need to disable the spi from
master->unprepare_message.

This also flushes the tx and rx fifos,
so no need to do that manually.

Signed-off-by: Emil Renner Berthing <kernel@xxxxxxxx>
Tested-by: Heiko Stuebner <heiko@xxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
drivers/spi/spi-rockchip.c | 30 +++++-------------------------
1 file changed, 5 insertions(+), 25 deletions(-)

diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 1c813797f963..5729e6071729 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -210,12 +210,6 @@ static inline void spi_set_clk(struct rockchip_spi *rs, u16 div)
writel_relaxed(div, rs->regs + ROCKCHIP_SPI_BAUDR);
}

-static inline void flush_fifo(struct rockchip_spi *rs)
-{
- while (readl_relaxed(rs->regs + ROCKCHIP_SPI_RXFLR))
- readl_relaxed(rs->regs + ROCKCHIP_SPI_RXDR);
-}
-
static inline void wait_for_idle(struct rockchip_spi *rs)
{
unsigned long timeout = jiffies + msecs_to_jiffies(5);
@@ -304,29 +298,16 @@ static void rockchip_spi_handle_err(struct spi_master *master,
{
struct rockchip_spi *rs = spi_master_get_devdata(master);

- /*
- * For DMA mode, we need terminate DMA channel and flush
- * fifo for the next transfer if DMA thansfer timeout.
- * handle_err() was called by core if transfer failed.
- * Maybe it is reasonable for error handling here.
+ /* stop running spi transfer
+ * this also flushes both rx and tx fifos
*/
+ spi_enable_chip(rs, false);
+
if (atomic_read(&rs->state) & TXDMA)
dmaengine_terminate_async(rs->dma_tx.ch);

- if (atomic_read(&rs->state) & RXDMA) {
+ if (atomic_read(&rs->state) & RXDMA)
dmaengine_terminate_async(rs->dma_rx.ch);
- flush_fifo(rs);
- }
-}
-
-static int rockchip_spi_unprepare_message(struct spi_master *master,
- struct spi_message *msg)
-{
- struct rockchip_spi *rs = spi_master_get_devdata(master);
-
- spi_enable_chip(rs, false);
-
- return 0;
}

static void rockchip_spi_pio_writer(struct rockchip_spi *rs)
@@ -705,7 +686,6 @@ static int rockchip_spi_probe(struct platform_device *pdev)

master->set_cs = rockchip_spi_set_cs;
master->prepare_message = rockchip_spi_prepare_message;
- master->unprepare_message = rockchip_spi_unprepare_message;
master->transfer_one = rockchip_spi_transfer_one;
master->max_transfer_size = rockchip_spi_max_transfer_size;
master->handle_err = rockchip_spi_handle_err;
--
2.19.0.rc2