[PATCH 2/4] spi/rockchip: call wait_for_idle() for the transfer to complete

From: Addy Ke
Date: Thu Jul 10 2014 - 22:08:48 EST


From: Addy Ke <addy.ke@xxxxxxxxxxxx>

Suggested-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Addy Ke <addy.ke@xxxxxxxxxxxx>
---
drivers/spi/spi-rockchip.c | 24 +++++++++++++++++++-----
1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 8c24708..09c690c 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -214,6 +214,18 @@ static inline void flush_fifo(struct rockchip_spi *rs)
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);
+
+ do {
+ if (!(readl_relaxed(rs->regs + ROCKCHIP_SPI_SR) & SR_BUSY))
+ return;
+ } while (time_before(jiffies, timeout));
+
+ dev_warn(rs->dev, "spi controller is in busy state!\n");
+}
+
static u32 get_fifo_len(struct rockchip_spi *rs)
{
u32 fifo;
@@ -371,6 +383,10 @@ static int rockchip_spi_pio_transfer(struct rockchip_spi *rs)
cpu_relax();
} while (remain);

+ /* If tx, wait until the FIFO data completely. */
+ if (rs->tx)
+ wait_for_idle(rs);
+
return 0;
}

@@ -393,6 +409,9 @@ static void rockchip_spi_dma_txcb(void *data)
unsigned long flags;
struct rockchip_spi *rs = data;

+ /* Wait until the FIFO data completely. */
+ wait_for_idle(rs);
+
spin_lock_irqsave(&rs->lock, flags);

rs->state &= ~TXBUSY;
@@ -536,11 +555,6 @@ static int rockchip_spi_transfer_one(
rs->tx_sg = xfer->tx_sg;
rs->rx_sg = xfer->rx_sg;

- /* Delay until the FIFO data completely */
- if (xfer->tx_buf)
- xfer->delay_usecs
- = rs->fifo_len * rs->bpw * 1000000 / rs->speed;
-
if (rs->tx && rs->rx)
rs->tmode = CR0_XFM_TR;
else if (rs->tx)
--
1.8.3.2


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