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

3 files changed, 12 insertions, 2 deletions

diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c
index 35c0dd945668..a67b0ff6a362 100644
--- a/drivers/spi/spi-fsl-dspi.c
+++ b/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");
diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c
index 7451585a080e..2c175b9495f7 100644
--- a/drivers/spi/spi-fsl-espi.c
+++ b/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);
         }
 
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 5787b723b593..838783c3fed0 100644
--- a/drivers/spi/spi.c
+++ b/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;