spi: cadence-quadspi: fix suspend-resume implementations

The cadence QSPI driver misbehaves after performing a full system suspend
resume:
...
spi-nor spi0.0: resume() failed
...
This results in a flash connected via OSPI interface after system suspend-
resume to be unusable.
fix these suspend and resume functions.

Fixes: 140623410536 ("mtd: spi-nor: Add driver for Cadence Quad SPI Flash Controller")
Signed-off-by: Dhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/r/20230417091027.966146-3-d-gole@ti.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
index d4a2b72..53829eb 100644 (file)
--- a/drivers/spi/spi-cadence-quadspi.c
+++ b/drivers/spi/spi-cadence-quadspi.c
@@ -1824,17 +1824,30 @@ static void cqspi_remove(struct platform_device *pdev)
 static int cqspi_suspend(struct device *dev)
 {
        struct cqspi_st *cqspi = dev_get_drvdata(dev);
+       struct spi_master *master = dev_get_drvdata(dev);
+       int ret;
 
+       ret = spi_master_suspend(master);
        cqspi_controller_enable(cqspi, 0);
-       return 0;
+
+       clk_disable_unprepare(cqspi->clk);
+
+       return ret;
 }
 
 static int cqspi_resume(struct device *dev)
 {
        struct cqspi_st *cqspi = dev_get_drvdata(dev);
+       struct spi_master *master = dev_get_drvdata(dev);
 
-       cqspi_controller_enable(cqspi, 1);
-       return 0;
+       clk_prepare_enable(cqspi->clk);
+       cqspi_wait_idle(cqspi);
+       cqspi_controller_init(cqspi);
+
+       cqspi->current_cs = -1;
+       cqspi->sclk = 0;
+
+       return spi_master_resume(master);
 }
 
 static const struct dev_pm_ops cqspi__dev_pm_ops = {