spi/rockchip: call wait_for_idle() for the transfer to complete

Suggested-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Addy Ke <addy.ke@rockchip.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 8c247086e520a2fb5bc011721f840e4043541e38..09c690c65956202f3792fb64208db9d35a623142 100644 (file)
--- 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)