This driver reuses pdev->id for spi bus numbers resulting in random
or very large bus numbering when used with device trees. pdev->id
is not the correct choice when using device trees. So add code to
get bus numbers via device tree aliases and if it fails then generate
a unique bus number.
Without this patch the driver get a random and useless bus number.
Signed-off-by: Srinivas Kandagatla <srinivas.kandaga...@linaro.org>
---
drivers/spi/spi-qup.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/spi-qup.c b/drivers/spi/spi-qup.c
index 810a7fa..2bc67a9 100644
--- a/drivers/spi/spi-qup.c
+++ b/drivers/spi/spi-qup.c
@@ -127,6 +127,8 @@
#define SPI_DELAY_THRESHOLD 1
#define SPI_DELAY_RETRY 10
+static atomic_t spi_qup_next_id = ATOMIC_INIT(0);
+
struct spi_qup {
void __iomem *base;
struct device *dev;
@@ -759,7 +761,7 @@ static int spi_qup_probe(struct platform_device *pdev)
struct device *dev;
void __iomem *base;
u32 max_freq, iomode, num_cs;
- int ret, irq, size;
+ int ret, irq, size, bus_num;
dev = &pdev->dev;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -816,7 +818,15 @@ static int spi_qup_probe(struct platform_device *pdev)
else
master->num_chipselect = num_cs;
- master->bus_num = pdev->id;
+ if (dev->of_node)
+ bus_num = of_alias_get_id(dev->of_node, "spi");
+ else
+ bus_num = pdev->id;
+
+ if (bus_num < 0)
+ bus_num = atomic_inc_return(&spi_qup_next_id) - 1;
+
+ master->bus_num = bus_num;
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
master->max_speed_hz = max_freq;
--
1.9.1
