[PATCH] spi: ma35d1-qspi: assert reset on probe error paths

["Li Youhong" <dayou5941@163.com>]

From: Li Youhong <liyouhong@kylinos.cn>

nuvoton_qspi_probe() pulses the exclusive reset and leaves it
deasserted for normal operation. Later probe failures returned
without re-asserting the reset, leaving the controller out of
reset after a failed probe. Assert the reset on those error
paths.

Fixes: 78b16af159ae ("spi: ma35d1-qspi: Add Nuvoton MA35D1 QSPI controller support")
Signed-off-by: Li Youhong <liyouhong@kylinos.cn>
---
 drivers/spi/spi-ma35d1-qspi.c | 26 ++++++++++++++++++--------
 1 file changed, 18 insertions(+), 8 deletions(-)

diff --git a/drivers/spi/spi-ma35d1-qspi.c b/drivers/spi/spi-ma35d1-qspi.c
index 7f938d0c6f1f..cf731fa2f7e2 100644
--- a/drivers/spi/spi-ma35d1-qspi.c
+++ b/drivers/spi/spi-ma35d1-qspi.c
@@ -633,12 +633,16 @@ static int nuvoton_qspi_probe(struct platform_device *pdev)
 		return dev_err_probe(dev, ret, "failed to deassert reset\n");
 
 	ret = device_property_read_u32(dev, "num-cs", &num_cs);
-	if (ret && ret != -EINVAL)
-		return dev_err_probe(dev, ret, "failed to read num-cs\n");
+	if (ret && ret != -EINVAL) {
+		ret = dev_err_probe(dev, ret, "failed to read num-cs\n");
+		goto err_assert;
+	}
 
-	if (!num_cs || num_cs > NUVOTON_QSPI_MAX_NUM_CS)
-		return dev_err_probe(dev, -EINVAL, "invalid num-cs %u\n",
+	if (!num_cs || num_cs > NUVOTON_QSPI_MAX_NUM_CS) {
+		ret = dev_err_probe(dev, -EINVAL, "invalid num-cs %u\n",
 				     num_cs);
+		goto err_assert;
+	}
 
 	ctlr->num_chipselect = num_cs;
 	ctlr->max_transfer_size = nuvoton_qspi_max_transfer_size;
@@ -655,14 +659,20 @@ static int nuvoton_qspi_probe(struct platform_device *pdev)
 
 	ret = nuvoton_qspi_hw_init(qspi);
 	if (ret)
-		return ret;
+		goto err_assert;
 
 	ret = devm_spi_register_controller(dev, ctlr);
-	if (ret)
-		return dev_err_probe(dev, ret,
-				     "failed to register spi controller\n");
+	if (ret) {
+		ret = dev_err_probe(dev, ret,
+				    "failed to register spi controller\n");
+		goto err_assert;
+	}
 
 	return 0;
+
+err_assert:
+	reset_control_assert(rst);
+	return ret;
 }
 
 static const struct of_device_id nuvoton_qspi_of_match[] = {
-- 
2.25.1