Merge tag 'spi-fix-v4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi fixes from Mark Brown: "A few small fixes for SPI, one core fix
  that only applies in cases where we're handling DT overlays and a
  couple of driver specific fixes:

   - Fix handling of error cases when instantiating DT overlays so we
     don't end up just ignoring devices that encountered an error during
     instantiation.

   - Avoid reading uninitialized data when handing spurious interrupts
     in the espi driver.

   - A driver specific fix for the dspi driver to fix a bad interaction
     with u-boot"

* tag 'spi-fix-v4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: dspi: clear SPI_SR before enable interrupt
  spi: fsl-espi: avoid processing uninitalized data on error
  spi: mark device nodes only in case of successful instantiation

Author: torvalds

drivers/spi/spi-fsl-dspi.c

@@ -70,6 +70,7 @@
 #define SPI_SR			0x2c
 #define SPI_SR_EOQF		0x10000000
 #define SPI_SR_TCFQF		0x80000000
+#define SPI_SR_CLEAR		0xdaad0000
 
 #define SPI_RSER		0x30
 #define SPI_RSER_EOQFE		0x10000000
@@ -646,6 +647,11 @@ static const struct regmap_config dspi_regmap_config = {
 	.max_register = 0x88,
 };
 
+static void dspi_init(struct fsl_dspi *dspi)
+{
+	regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR);
+}
+
 static int dspi_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
@@ -709,6 +715,7 @@ static int dspi_probe(struct platform_device *pdev)
 		return PTR_ERR(dspi->regmap);
 	}
 
+	dspi_init(dspi);
 	dspi->irq = platform_get_irq(pdev, 0);
 	if (dspi->irq < 0) {
 		dev_err(&pdev->dev, "can't get platform irq\n");

drivers/spi/spi-fsl-espi.c

@@ -458,7 +458,7 @@ static void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
 
 		mspi->len -= rx_nr_bytes;
 
-		if (mspi->rx)
+		if (rx_nr_bytes && mspi->rx)
 			mspi->get_rx(rx_data, mspi);
 	}
 

drivers/spi/spi.c

@@ -1618,9 +1618,11 @@ static void of_register_spi_devices(struct spi_master *master)
 		if (of_node_test_and_set_flag(nc, OF_POPULATED))
 			continue;
 		spi = of_register_spi_device(master, nc);
-		if (IS_ERR(spi))
+		if (IS_ERR(spi)) {
 			dev_warn(&master->dev, "Failed to create SPI device for %s\n",
 				nc->full_name);
+			of_node_clear_flag(nc, OF_POPULATED);
+		}
 	}
 }
 #else
@@ -3131,6 +3133,7 @@ static int of_spi_notify(struct notifier_block *nb, unsigned long action,
 		if (IS_ERR(spi)) {
 			pr_err("%s: failed to create for '%s'\n",
 					__func__, rd->dn->full_name);
+			of_node_clear_flag(rd->dn, OF_POPULATED);
 			return notifier_from_errno(PTR_ERR(spi));
 		}
 		break;