net: dsa: Add support for a switch reset gpio
Some boards have a gpio line tied to the switch reset pin. Allow this
gpio to be retrieved from the device tree, and take the switch out of
reset before performing the probe.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 1eba07f..0b5565f 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -21,6 +21,7 @@
#include <linux/of_mdio.h>
#include <linux/of_platform.h>
#include <linux/of_net.h>
+#include <linux/of_gpio.h>
#include <linux/sysfs.h>
#include <linux/phy_fixed.h>
#include "dsa_priv.h"
@@ -688,6 +689,9 @@
const char *port_name;
int chip_index, port_index;
const unsigned int *sw_addr, *port_reg;
+ int gpio;
+ enum of_gpio_flags of_flags;
+ unsigned long flags;
u32 eeprom_len;
int ret;
@@ -766,6 +770,19 @@
put_device(cd->host_dev);
cd->host_dev = &mdio_bus_switch->dev;
}
+ gpio = of_get_named_gpio_flags(child, "reset-gpios", 0,
+ &of_flags);
+ if (gpio_is_valid(gpio)) {
+ flags = (of_flags == OF_GPIO_ACTIVE_LOW ?
+ GPIOF_ACTIVE_LOW : 0);
+ ret = devm_gpio_request_one(dev, gpio, flags,
+ "switch_reset");
+ if (ret)
+ goto out_free_chip;
+
+ cd->reset = gpio_to_desc(gpio);
+ gpiod_direction_output(cd->reset, 0);
+ }
for_each_available_child_of_node(child, port) {
port_reg = of_get_property(port, "reg", NULL);