[PATCH] spi: tegra: Fix missing IRQ check in tegra_slink_probe()

[Zhang Shurong <zhang_shurong@foxmail.com>]

This func misses checking for platform_get_irq()'s call and may passes the
negative error codes to request_irq(), which takes unsigned IRQ #,
causing it to fail with -EINVAL, overriding an original error code.

Fix this by stop calling request_irq() with invalid IRQ #s.

Fixes: dc4dc3605639 ("spi: tegra: add spi driver for SLINK controller")
Signed-off-by: Zhang Shurong <zhang_shurong@foxmail.com>
---
 drivers/spi/spi-tegra20-slink.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/spi/spi-tegra20-slink.c b/drivers/spi/spi-tegra20-slink.c
index 4d6db6182c5e..f5cd365c913a 100644
--- a/drivers/spi/spi-tegra20-slink.c
+++ b/drivers/spi/spi-tegra20-slink.c
@@ -1086,6 +1086,8 @@ static int tegra_slink_probe(struct platform_device *pdev)
 	reset_control_deassert(tspi->rst);
 
 	spi_irq = platform_get_irq(pdev, 0);
+	if (spi_irq < 0)
+		return spi_irq;
 	tspi->irq = spi_irq;
 	ret = request_threaded_irq(tspi->irq, tegra_slink_isr,
 				   tegra_slink_isr_thread, IRQF_ONESHOT,
-- 
2.30.2