[V2][PATCH 2/5] spi: spi-zynqmp-gqspi: fix hang issue when suspend/resume

[quanyang.wang at windriver.com]

From: Quanyang Wang <quanyang.wang at windriver.com>

After calling platform_set_drvdata(pdev, xqspi) in probe, the return
value of dev_get_drvdata(dev) is a pointer to struct zynqmp_qspi but
not struct spi_controller. A wrong structure type passing to the
functions spi_controller_suspend/resume will hang the system.

And we should check the return value of spi_controller_suspend, if
an error is returned, return it to PM subsystem to stop suspend.

Also, GQSPI_EN_MASK should be written to GQSPI_EN_OFST to enable
the spi controller in zynqmp_qspi_resume since it was disabled in
zynqmp_qspi_suspend before.

Signed-off-by: Quanyang Wang <quanyang.wang at windriver.com>
---
 drivers/spi/spi-zynqmp-gqspi.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/spi/spi-zynqmp-gqspi.c b/drivers/spi/spi-zynqmp-gqspi.c
index f9056f0a480c..1146359528b9 100644
--- a/drivers/spi/spi-zynqmp-gqspi.c
+++ b/drivers/spi/spi-zynqmp-gqspi.c
@@ -157,6 +157,7 @@ enum mode_type {GQSPI_MODE_IO, GQSPI_MODE_DMA};
  * @data_completion:	completion structure
  */
 struct zynqmp_qspi {
+	struct spi_controller *ctlr;
 	void __iomem *regs;
 	struct clk *refclk;
 	struct clk *pclk;
@@ -827,10 +828,13 @@ static void zynqmp_qspi_read_op(struct zynqmp_qspi *xqspi, u8 rx_nbits,
  */
 static int __maybe_unused zynqmp_qspi_suspend(struct device *dev)
 {
-	struct spi_controller *ctlr = dev_get_drvdata(dev);
-	struct zynqmp_qspi *xqspi = spi_controller_get_devdata(ctlr);
+	struct zynqmp_qspi *xqspi = dev_get_drvdata(dev);
+	struct spi_controller *ctlr = xqspi->ctlr;
+	int ret;
 
-	spi_controller_suspend(ctlr);
+	ret = spi_controller_suspend(ctlr);
+	if (ret)
+		return ret;
 
 	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, 0x0);
 
@@ -848,7 +852,10 @@ static int __maybe_unused zynqmp_qspi_suspend(struct device *dev)
  */
 static int __maybe_unused zynqmp_qspi_resume(struct device *dev)
 {
-	struct spi_controller *ctlr = dev_get_drvdata(dev);
+	struct zynqmp_qspi *xqspi = dev_get_drvdata(dev);
+	struct spi_controller *ctlr = xqspi->ctlr;
+
+	zynqmp_gqspi_write(xqspi, GQSPI_EN_OFST, GQSPI_EN_MASK);
 
 	spi_controller_resume(ctlr);
 
@@ -865,7 +872,7 @@ static int __maybe_unused zynqmp_qspi_resume(struct device *dev)
  */
 static int __maybe_unused zynqmp_runtime_suspend(struct device *dev)
 {
-	struct zynqmp_qspi *xqspi = (struct zynqmp_qspi *)dev_get_drvdata(dev);
+	struct zynqmp_qspi *xqspi = dev_get_drvdata(dev);
 
 	clk_disable_unprepare(xqspi->refclk);
 	clk_disable_unprepare(xqspi->pclk);
@@ -883,7 +890,7 @@ static int __maybe_unused zynqmp_runtime_suspend(struct device *dev)
  */
 static int __maybe_unused zynqmp_runtime_resume(struct device *dev)
 {
-	struct zynqmp_qspi *xqspi = (struct zynqmp_qspi *)dev_get_drvdata(dev);
+	struct zynqmp_qspi *xqspi = dev_get_drvdata(dev);
 	int ret;
 
 	ret = clk_prepare_enable(xqspi->pclk);
@@ -1090,6 +1097,7 @@ static int zynqmp_qspi_probe(struct platform_device *pdev)
 
 	xqspi = spi_controller_get_devdata(ctlr);
 	xqspi->dev = dev;
+	xqspi->ctlr = ctlr;
 	platform_set_drvdata(pdev, xqspi);
 
 	xqspi->regs = devm_platform_ioremap_resource(pdev, 0);
-- 
2.25.1