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;
 	}