dw_spi: Fix missing final read in some polling situations

[linux-2.6.git] / drivers / spi / dw_spi.c

diff --git a/drivers/spi/dw_spi.c b/drivers/spi/dw_spi.c
index a32aa66d66bfe2f4e9f3025104dcf5df928afe64..0838c79861e49f9a0c97189af9ab25d3c0269b76 100644 (file)
--- a/drivers/spi/dw_spi.c
+++ b/drivers/spi/dw_spi.c
@@ -182,10 +182,6 @@ static void flush(struct dw_spi *dws)
        wait_till_not_busy(dws);
 }
 
-static void null_cs_control(u32 command)
-{
-}
-
 static int null_writer(struct dw_spi *dws)
 {
        u8 n_bytes = dws->n_bytes;
@@ -323,7 +319,7 @@ static void giveback(struct dw_spi *dws)
                                        struct spi_transfer,
                                        transfer_list);
 
-       if (!last_transfer->cs_change)
+       if (!last_transfer->cs_change && dws->cs_control)
                dws->cs_control(MRST_SPI_DEASSERT);
 
        msg->state = NULL;
@@ -397,6 +393,11 @@ static irqreturn_t interrupt_transfer(struct dw_spi *dws)
 static irqreturn_t dw_spi_irq(int irq, void *dev_id)
 {
        struct dw_spi *dws = dev_id;
+       u16 irq_status, irq_mask = 0x3f;
+
+       irq_status = dw_readw(dws, isr) & irq_mask;
+       if (!irq_status)
+               return IRQ_NONE;
 
        if (!dws->cur_msg) {
                spi_mask_intr(dws, SPI_INT_TXEI);
@@ -412,6 +413,11 @@ static void poll_transfer(struct dw_spi *dws)
 {
        while (dws->write(dws))
                dws->read(dws);
+       /*
+        * There is a possibility that the last word of a transaction
+        * will be lost if data is not ready. Re-read to solve this issue.
+        */
+       dws->read(dws);
 
        transfer_complete(dws);
 }
@@ -545,13 +551,13 @@ static void pump_transfers(unsigned long data)
         */
        if (dws->cs_control) {
                if (dws->rx && dws->tx)
-                       chip->tmode = 0x00;
+                       chip->tmode = SPI_TMOD_TR;
                else if (dws->rx)
-                       chip->tmode = 0x02;
+                       chip->tmode = SPI_TMOD_RO;
                else
-                       chip->tmode = 0x01;
+                       chip->tmode = SPI_TMOD_TO;
 
-               cr0 &= ~(0x3 << SPI_MODE_OFFSET);
+               cr0 &= ~SPI_TMOD_MASK;
                cr0 |= (chip->tmode << SPI_TMOD_OFFSET);
        }
 
@@ -700,9 +706,6 @@ static int dw_spi_setup(struct spi_device *spi)
                chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
                if (!chip)
                        return -ENOMEM;
-
-               chip->cs_control = null_cs_control;
-               chip->enable_dma = 0;
        }
 
        /*
@@ -884,7 +887,7 @@ int __devinit dw_spi_add_host(struct dw_spi *dws)
        dws->dma_inited = 0;
        dws->dma_addr = (dma_addr_t)(dws->paddr + 0x60);
 
-       ret = request_irq(dws->irq, dw_spi_irq, 0,
+       ret = request_irq(dws->irq, dw_spi_irq, IRQF_SHARED,
                        "dw_spi", dws);
        if (ret < 0) {
                dev_err(&master->dev, "can not get IRQ\n");