1 files changed, 68 insertions, 21 deletions

diff --git a/drivers/spi/spi-uniphier.c b/drivers/spi/spi-uniphier.c
index 4e99a0f25c29..47cde1864630 100644
--- a/drivers/spi/spi-uniphier.c
+++ b/drivers/spi/spi-uniphier.c
@@ -7,6 +7,7 @@
 #include <linux/bitfield.h>
 #include <linux/bitops.h>
 #include <linux/clk.h>
+#include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/module.h>
@@ -16,6 +17,7 @@
 #include <asm/unaligned.h>
 
 #define SSI_TIMEOUT_MS          2000
+#define SSI_POLL_TIMEOUT_US     200
 #define SSI_MAX_CLK_DIVIDER     254
 #define SSI_MIN_CLK_DIVIDER     4
 
@@ -227,8 +229,7 @@ static void uniphier_spi_setup_transfer(struct spi_device *spi,
                 priv->speed_hz = t->speed_hz;
         }
 
-        if (!priv->is_save_param)
-                priv->is_save_param = true;
+        priv->is_save_param = true;
 
         /* reset FIFOs */
         val = SSI_FC_TXFFL | SSI_FC_RXFFL;
@@ -291,21 +292,23 @@ static void uniphier_spi_recv(struct uniphier_spi_priv *priv)
 
 static void uniphier_spi_fill_tx_fifo(struct uniphier_spi_priv *priv)
 {
-        unsigned int tx_count;
+        unsigned int fifo_threshold, fill_bytes;
         u32 val;
 
-        tx_count = DIV_ROUND_UP(priv->tx_bytes,
+        fifo_threshold = DIV_ROUND_UP(priv->rx_bytes,
                                 bytes_per_word(priv->bits_per_word));
-        tx_count = min(tx_count, SSI_FIFO_DEPTH);
+        fifo_threshold = min(fifo_threshold, SSI_FIFO_DEPTH);
+
+        fill_bytes = fifo_threshold - (priv->rx_bytes - priv->tx_bytes);
 
         /* set fifo threshold */
         val = readl(priv->base + SSI_FC);
         val &= ~(SSI_FC_TXFTH_MASK | SSI_FC_RXFTH_MASK);
-        val |= FIELD_PREP(SSI_FC_TXFTH_MASK, tx_count);
-        val |= FIELD_PREP(SSI_FC_RXFTH_MASK, tx_count);
+        val |= FIELD_PREP(SSI_FC_TXFTH_MASK, fifo_threshold);
+        val |= FIELD_PREP(SSI_FC_RXFTH_MASK, fifo_threshold);
         writel(val, priv->base + SSI_FC);
 
-        while (tx_count--)
+        while (fill_bytes--)
                 uniphier_spi_send(priv);
 }
 
@@ -324,20 +327,14 @@ static void uniphier_spi_set_cs(struct spi_device *spi, bool enable)
         writel(val, priv->base + SSI_FPS);
 }
 
-static int uniphier_spi_transfer_one(struct spi_master *master,
-                                     struct spi_device *spi,
-                                     struct spi_transfer *t)
+static int uniphier_spi_transfer_one_irq(struct spi_master *master,
+                                         struct spi_device *spi,
+                                         struct spi_transfer *t)
 {
         struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
         struct device *dev = master->dev.parent;
         unsigned long time_left;
 
-        /* Terminate and return success for 0 byte length transfer */
-        if (!t->len)
-                return 0;
-
-        uniphier_spi_setup_transfer(spi, t);
-
         reinit_completion(&priv->xfer_done);
 
         uniphier_spi_fill_tx_fifo(priv);
@@ -357,6 +354,59 @@ static int uniphier_spi_transfer_one(struct spi_master *master,
         return priv->error;
 }
 
+static int uniphier_spi_transfer_one_poll(struct spi_master *master,
+                                          struct spi_device *spi,
+                                          struct spi_transfer *t)
+{
+        struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+        int loop = SSI_POLL_TIMEOUT_US * 10;
+
+        while (priv->tx_bytes) {
+                uniphier_spi_fill_tx_fifo(priv);
+
+                while ((priv->rx_bytes - priv->tx_bytes) > 0) {
+                        while (!(readl(priv->base + SSI_SR) & SSI_SR_RNE)
+                                                                && loop--)
+                                ndelay(100);
+
+                        if (loop == -1)
+                                goto irq_transfer;
+
+                        uniphier_spi_recv(priv);
+                }
+        }
+
+        return 0;
+
+irq_transfer:
+        return uniphier_spi_transfer_one_irq(master, spi, t);
+}
+
+static int uniphier_spi_transfer_one(struct spi_master *master,
+                                     struct spi_device *spi,
+                                     struct spi_transfer *t)
+{
+        struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
+        unsigned long threshold;
+
+        /* Terminate and return success for 0 byte length transfer */
+        if (!t->len)
+                return 0;
+
+        uniphier_spi_setup_transfer(spi, t);
+
+        /*
+         * If the transfer operation will take longer than
+         * SSI_POLL_TIMEOUT_US, it should use irq.
+         */
+        threshold = DIV_ROUND_UP(SSI_POLL_TIMEOUT_US * priv->speed_hz,
+                                        USEC_PER_SEC * BITS_PER_BYTE);
+        if (t->len > threshold)
+                return uniphier_spi_transfer_one_irq(master, spi, t);
+        else
+                return uniphier_spi_transfer_one_poll(master, spi, t);
+}
+
 static int uniphier_spi_prepare_transfer_hardware(struct spi_master *master)
 {
         struct uniphier_spi_priv *priv = spi_master_get_devdata(master);
@@ -420,7 +470,6 @@ static int uniphier_spi_probe(struct platform_device *pdev)
 {
         struct uniphier_spi_priv *priv;
         struct spi_master *master;
-        struct resource *res;
         unsigned long clk_rate;
         int irq;
         int ret;
@@ -435,8 +484,7 @@ static int uniphier_spi_probe(struct platform_device *pdev)
         priv->master = master;
         priv->is_save_param = false;
 
-        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-        priv->base = devm_ioremap_resource(&pdev->dev, res);
+        priv->base = devm_platform_ioremap_resource(pdev, 0);
         if (IS_ERR(priv->base)) {
                 ret = PTR_ERR(priv->base);
                 goto out_master_put;
@@ -455,7 +503,6 @@ static int uniphier_spi_probe(struct platform_device *pdev)
 
         irq = platform_get_irq(pdev, 0);
         if (irq < 0) {
-                dev_err(&pdev->dev, "failed to get IRQ\n");
                 ret = irq;
                 goto out_disable_clk;
         }