[U-Boot] [PATCH] gpio: dwapb_gpio: Add reset ctrl to driver

Ley Foon Tan ley.foon.tan at intel.com
Wed Aug 15 18:05:53 UTC 2018


Add code to reset all reset signals as in gpio DT node. A reset property
is an optional feature, so only print out a warning and do not fail if a
reset property is not present.

If a reset property is discovered, then use it to deassert, thus
bringing the IP out of reset.

Signed-off-by: Ley Foon Tan <ley.foon.tan at intel.com>
---
 drivers/gpio/dwapb_gpio.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/drivers/gpio/dwapb_gpio.c b/drivers/gpio/dwapb_gpio.c
index 3b5c181..e2b6e69 100644
--- a/drivers/gpio/dwapb_gpio.c
+++ b/drivers/gpio/dwapb_gpio.c
@@ -15,6 +15,7 @@
 #include <dm/lists.h>
 #include <dm/root.h>
 #include <errno.h>
+#include <reset.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -114,6 +115,20 @@ static int gpio_dwapb_probe(struct udevice *dev)
 	return 0;
 }
 
+static void gpio_dwapb_reset(struct udevice *dev)
+{
+	struct reset_ctl_bulk reset_bulk;
+	int ret;
+
+	ret = reset_get_bulk(dev, &reset_bulk);
+	if (ret) {
+		dev_warn(dev, "Can't get reset: %d\n", ret);
+		return;
+	}
+
+	reset_deassert_bulk(&reset_bulk);
+}
+
 static int gpio_dwapb_bind(struct udevice *dev)
 {
 	struct gpio_dwapb_platdata *plat = dev_get_platdata(dev);
@@ -126,6 +141,8 @@ static int gpio_dwapb_bind(struct udevice *dev)
 	if (plat)
 		return 0;
 
+	gpio_dwapb_reset(dev);
+
 	base = dev_read_addr(dev);
 	if (base == FDT_ADDR_T_NONE) {
 		debug("Can't get the GPIO register base address\n");
-- 
2.2.2



More information about the U-Boot mailing list