[PATCH 2/4] spi: sprd: Add the SPI irq function for the SPI DMA mode

[Baolin Wang]

From: Lanqing Liu <lanqing....@spreadtrum.com>

The SPI irq event will use to complete the SPI work in the SPI DMA mode,
so this patch is a preparation for the following DMA mode support.

Signed-off-by: Lanqing Liu <lanqing....@spreadtrum.com>
Signed-off-by: Baolin Wang <baolin.w...@linaro.org>
---
 drivers/spi/spi-sprd.c |   46 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/drivers/spi/spi-sprd.c b/drivers/spi/spi-sprd.c
index fa324ce..bfba30b 100644
--- a/drivers/spi/spi-sprd.c
+++ b/drivers/spi/spi-sprd.c
@@ -133,6 +133,7 @@ struct sprd_spi {
        void __iomem *base;
        struct device *dev;
        struct clk *clk;
+       int irq;
        u32 src_clk;
        u32 hw_mode;
        u32 trans_len;
@@ -141,6 +142,7 @@ struct sprd_spi {
        u32 hw_speed_hz;
        u32 len;
        int status;
+       struct completion xfer_completion;
        const void *tx_buf;
        void *rx_buf;
        int (*read_bufs)(struct sprd_spi *ss, u32 len);
@@ -575,6 +577,45 @@ static int sprd_spi_transfer_one(struct spi_controller 
*sctlr,
        return ret;
 }
 
+static irqreturn_t sprd_spi_handle_irq(int irq, void *data)
+{
+       struct sprd_spi *ss = (struct sprd_spi *)data;
+       u32 val = readl_relaxed(ss->base + SPRD_SPI_INT_MASK_STS);
+
+       if (val & SPRD_SPI_MASK_TX_END) {
+               writel_relaxed(SPRD_SPI_TX_END_CLR, ss->base + 
SPRD_SPI_INT_CLR);
+               if (!(ss->trans_mode & SPRD_SPI_RX_MODE))
+                       complete(&ss->xfer_completion);
+               return IRQ_HANDLED;
+       }
+
+       if (val & SPRD_SPI_MASK_RX_END) {
+               writel_relaxed(SPRD_SPI_RX_END_CLR, ss->base + 
SPRD_SPI_INT_CLR);
+               complete(&ss->xfer_completion);
+       }
+
+       return IRQ_HANDLED;
+}
+
+static int sprd_spi_irq_init(struct platform_device *pdev, struct sprd_spi *ss)
+{
+       int ret;
+
+       ss->irq = platform_get_irq(pdev, 0);
+       if (ss->irq < 0) {
+               dev_err(&pdev->dev, "failed to get irq resource\n");
+               return ss->irq;
+       }
+
+       ret = devm_request_irq(&pdev->dev, ss->irq, sprd_spi_handle_irq,
+                               0, pdev->name, ss);
+       if (ret)
+               dev_err(&pdev->dev, "failed to request spi irq %d, ret = %d\n",
+                       ss->irq, ret);
+
+       return ret;
+}
+
 static int sprd_spi_clk_init(struct platform_device *pdev, struct sprd_spi *ss)
 {
        struct clk *clk_spi, *clk_parent;
@@ -635,11 +676,16 @@ static int sprd_spi_probe(struct platform_device *pdev)
        sctlr->max_speed_hz = min_t(u32, ss->src_clk >> 1,
                                    SPRD_SPI_MAX_SPEED_HZ);
 
+       init_completion(&ss->xfer_completion);
        platform_set_drvdata(pdev, sctlr);
        ret = sprd_spi_clk_init(pdev, ss);
        if (ret)
                goto free_controller;
 
+       ret = sprd_spi_irq_init(pdev, ss);
+       if (ret)
+               goto free_controller;
+
        ret = clk_prepare_enable(ss->clk);
        if (ret)
                goto free_controller;
-- 
1.7.9.5