1 files changed, 48 insertions, 44 deletions

diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c
index 08dcc3c22e88..391863914043 100644
--- a/drivers/spi/spi-fsl-lpspi.c
+++ b/drivers/spi/spi-fsl-lpspi.c
@@ -48,10 +48,13 @@
 #define CR_RTF          BIT(8)
 #define CR_RST          BIT(1)
 #define CR_MEN          BIT(0)
+#define SR_MBF          BIT(24)
 #define SR_TCF          BIT(10)
+#define SR_FCF          BIT(9)
 #define SR_RDF          BIT(1)
 #define SR_TDF          BIT(0)
 #define IER_TCIE        BIT(10)
+#define IER_FCIE        BIT(9)
 #define IER_RDIE        BIT(1)
 #define IER_TDIE        BIT(0)
 #define CFGR1_PCSCFG    BIT(27)
@@ -59,6 +62,7 @@
 #define CFGR1_PCSPOL    BIT(8)
 #define CFGR1_NOSTALL   BIT(3)
 #define CFGR1_MASTER    BIT(0)
+#define FSR_RXCOUNT     (BIT(16)|BIT(17)|BIT(18))
 #define RSR_RXEMPTY     BIT(1)
 #define TCR_CPOL        BIT(31)
 #define TCR_CPHA        BIT(30)
@@ -161,28 +165,10 @@ static int lpspi_unprepare_xfer_hardware(struct spi_controller *controller)
         return 0;
 }
 
-static int fsl_lpspi_txfifo_empty(struct fsl_lpspi_data *fsl_lpspi)
-{
-        u32 txcnt;
-        unsigned long orig_jiffies = jiffies;
-
-        do {
-                txcnt = readl(fsl_lpspi->base + IMX7ULP_FSR) & 0xff;
-
-                if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
-                        dev_dbg(fsl_lpspi->dev, "txfifo empty timeout\n");
-                        return -ETIMEDOUT;
-                }
-                cond_resched();
-
-        } while (txcnt);
-
-        return 0;
-}
-
 static void fsl_lpspi_write_tx_fifo(struct fsl_lpspi_data *fsl_lpspi)
 {
         u8 txfifo_cnt;
+        u32 temp;
 
         txfifo_cnt = readl(fsl_lpspi->base + IMX7ULP_FSR) & 0xff;
 
@@ -193,9 +179,15 @@ static void fsl_lpspi_write_tx_fifo(struct fsl_lpspi_data *fsl_lpspi)
                 txfifo_cnt++;
         }
 
-        if (!fsl_lpspi->remain && (txfifo_cnt < fsl_lpspi->txfifosize))
-                writel(0, fsl_lpspi->base + IMX7ULP_TDR);
-        else
+        if (txfifo_cnt < fsl_lpspi->txfifosize) {
+                if (!fsl_lpspi->is_slave) {
+                        temp = readl(fsl_lpspi->base + IMX7ULP_TCR);
+                        temp &= ~TCR_CONTC;
+                        writel(temp, fsl_lpspi->base + IMX7ULP_TCR);
+                }
+
+                fsl_lpspi_intctrl(fsl_lpspi, IER_FCIE);
+        } else
                 fsl_lpspi_intctrl(fsl_lpspi, IER_TDIE);
 }
 
@@ -276,10 +268,6 @@ static int fsl_lpspi_config(struct fsl_lpspi_data *fsl_lpspi)
         u32 temp;
         int ret;
 
-        temp = CR_RST;
-        writel(temp, fsl_lpspi->base + IMX7ULP_CR);
-        writel(0, fsl_lpspi->base + IMX7ULP_CR);
-
         if (!fsl_lpspi->is_slave) {
                 ret = fsl_lpspi_set_bitrate(fsl_lpspi);
                 if (ret)
@@ -370,6 +358,24 @@ static int fsl_lpspi_wait_for_completion(struct spi_controller *controller)
         return 0;
 }
 
+static int fsl_lpspi_reset(struct fsl_lpspi_data *fsl_lpspi)
+{
+        u32 temp;
+
+        /* Disable all interrupt */
+        fsl_lpspi_intctrl(fsl_lpspi, 0);
+
+        /* W1C for all flags in SR */
+        temp = 0x3F << 8;
+        writel(temp, fsl_lpspi->base + IMX7ULP_SR);
+
+        /* Clear FIFO and disable module */
+        temp = CR_RRF | CR_RTF;
+        writel(temp, fsl_lpspi->base + IMX7ULP_CR);
+
+        return 0;
+}
+
 static int fsl_lpspi_transfer_one(struct spi_controller *controller,
                                   struct spi_device *spi,
                                   struct spi_transfer *t)
@@ -391,11 +397,7 @@ static int fsl_lpspi_transfer_one(struct spi_controller *controller,
         if (ret)
                 return ret;
 
-        ret = fsl_lpspi_txfifo_empty(fsl_lpspi);
-        if (ret)
-                return ret;
-
-        fsl_lpspi_read_rx_fifo(fsl_lpspi);
+        fsl_lpspi_reset(fsl_lpspi);
 
         return 0;
 }
@@ -408,7 +410,6 @@ static int fsl_lpspi_transfer_one_msg(struct spi_controller *controller,
         struct spi_device *spi = msg->spi;
         struct spi_transfer *xfer;
         bool is_first_xfer = true;
-        u32 temp;
         int ret = 0;
 
         msg->status = 0;
@@ -428,13 +429,6 @@ static int fsl_lpspi_transfer_one_msg(struct spi_controller *controller,
         }
 
 complete:
-        if (!fsl_lpspi->is_slave) {
-                /* de-assert SS, then finalize current message */
-                temp = readl(fsl_lpspi->base + IMX7ULP_TCR);
-                temp &= ~TCR_CONTC;
-                writel(temp, fsl_lpspi->base + IMX7ULP_TCR);
-        }
-
         msg->status = ret;
         spi_finalize_current_message(controller);
 
@@ -443,20 +437,30 @@ complete:
 
 static irqreturn_t fsl_lpspi_isr(int irq, void *dev_id)
 {
+        u32 temp_SR, temp_IER;
         struct fsl_lpspi_data *fsl_lpspi = dev_id;
-        u32 temp;
 
+        temp_IER = readl(fsl_lpspi->base + IMX7ULP_IER);
         fsl_lpspi_intctrl(fsl_lpspi, 0);
-        temp = readl(fsl_lpspi->base + IMX7ULP_SR);
+        temp_SR = readl(fsl_lpspi->base + IMX7ULP_SR);
 
         fsl_lpspi_read_rx_fifo(fsl_lpspi);
 
-        if (temp & SR_TDF) {
+        if ((temp_SR & SR_TDF) && (temp_IER & IER_TDIE)) {
                 fsl_lpspi_write_tx_fifo(fsl_lpspi);
+                return IRQ_HANDLED;
+        }
 
-                if (!fsl_lpspi->remain)
-                        complete(&fsl_lpspi->xfer_done);
+        if (temp_SR & SR_MBF ||
+            readl(fsl_lpspi->base + IMX7ULP_FSR) & FSR_RXCOUNT) {
+                writel(SR_FCF, fsl_lpspi->base + IMX7ULP_SR);
+                fsl_lpspi_intctrl(fsl_lpspi, IER_FCIE);
+                return IRQ_HANDLED;
+        }
 
+        if (temp_SR & SR_FCF && (temp_IER & IER_FCIE)) {
+                writel(SR_FCF, fsl_lpspi->base + IMX7ULP_SR);
+                        complete(&fsl_lpspi->xfer_done);
                 return IRQ_HANDLED;
         }