[PATCH] mtd: spi-nor: cadence-quadspi: add reset control

[Dinh Nguyen]

Get the reset control for the QSPI controller and bring it out of reset.

Suggested-by: Tien-Fong Chee <tien.fong.c...@intel.com>
Signed-off-by: Dinh Nguyen <dingu...@kernel.org>
---
 drivers/mtd/spi-nor/cadence-quadspi.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/mtd/spi-nor/cadence-quadspi.c 
b/drivers/mtd/spi-nor/cadence-quadspi.c
index 792628750eec..710a853f9d13 100644
--- a/drivers/mtd/spi-nor/cadence-quadspi.c
+++ b/drivers/mtd/spi-nor/cadence-quadspi.c
@@ -34,6 +34,7 @@
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
+#include <linux/reset.h>
 #include <linux/sched.h>
 #include <linux/spi/spi.h>
 #include <linux/timer.h>
@@ -1336,6 +1337,7 @@ static int cqspi_probe(struct platform_device *pdev)
        struct cqspi_st *cqspi;
        struct resource *res;
        struct resource *res_ahb;
+       struct reset_control *rstc;
        const struct cqspi_driver_platdata *ddata;
        int ret;
        int irq;
@@ -1362,6 +1364,14 @@ static int cqspi_probe(struct platform_device *pdev)
                return PTR_ERR(cqspi->clk);
        }
 
+       /* Obtain QSPI reset control */
+       rstc = devm_reset_control_get_exclusive(dev, NULL);
+       if (!IS_ERR(rstc)) {
+               reset_control_assert(rstc);
+               udelay(1);
+               reset_control_deassert(rstc);
+       }
+
        /* Obtain and remap controller address. */
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        cqspi->iobase = devm_ioremap_resource(dev, res);
-- 
2.20.0