Merge branch 'for-4.8/core' of git://git.kernel.dk/linux-block

[karo-tx-linux.git] / drivers / spi / spi-sun4i.c

diff --git a/drivers/spi/spi-sun4i.c b/drivers/spi/spi-sun4i.c
index 1ddd9e2309b685576a8c63abc1770f731a7acd0c..cf007f3b83ec92f1d8f976ea2b68978dbdd36f20 100644 (file)
--- a/drivers/spi/spi-sun4i.c
+++ b/drivers/spi/spi-sun4i.c
@@ -173,13 +173,17 @@ static int sun4i_spi_transfer_one(struct spi_master *master,
 {
        struct sun4i_spi *sspi = spi_master_get_devdata(master);
        unsigned int mclk_rate, div, timeout;
+       unsigned int start, end, tx_time;
        unsigned int tx_len = 0;
        int ret = 0;
        u32 reg;
 
        /* We don't support transfer larger than the FIFO */
        if (tfr->len > SUN4I_FIFO_DEPTH)
-               return -EINVAL;
+               return -EMSGSIZE;
+
+       if (tfr->tx_buf && tfr->len >= SUN4I_FIFO_DEPTH)
+               return -EMSGSIZE;
 
        reinit_completion(&sspi->done);
        sspi->tx_buf = tfr->tx_buf;
@@ -269,8 +273,12 @@ static int sun4i_spi_transfer_one(struct spi_master *master,
        sun4i_spi_write(sspi, SUN4I_BURST_CNT_REG, SUN4I_BURST_CNT(tfr->len));
        sun4i_spi_write(sspi, SUN4I_XMIT_CNT_REG, SUN4I_XMIT_CNT(tx_len));
 
-       /* Fill the TX FIFO */
-       sun4i_spi_fill_fifo(sspi, SUN4I_FIFO_DEPTH);
+       /*
+        * Fill the TX FIFO
+        * Filling the FIFO fully causes timeout for some reason
+        * at least on spi2 on A10s
+        */
+       sun4i_spi_fill_fifo(sspi, SUN4I_FIFO_DEPTH - 1);
 
        /* Enable the interrupts */
        sun4i_spi_write(sspi, SUN4I_INT_CTL_REG, SUN4I_INT_CTL_TC);
@@ -279,9 +287,16 @@ static int sun4i_spi_transfer_one(struct spi_master *master,
        reg = sun4i_spi_read(sspi, SUN4I_CTL_REG);
        sun4i_spi_write(sspi, SUN4I_CTL_REG, reg | SUN4I_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(1000));
+                                             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;
        }