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>
This commit is contained in:
Andrew Lunn 2015-11-20 03:56:23 +01:00 committed by David S. Miller
parent 3f8c0f7efb
commit cc30c16344
3 changed files with 28 additions and 0 deletions

View File

@ -31,6 +31,8 @@ A switch child node has the following optional property:
switch. Must be set if the switch can not detect
the presence and/or size of a connected EEPROM,
otherwise optional.
- reset-gpios : phandle and specifier to a gpio line connected to
reset pin of the switch chip.
A switch may have multiple "port" children nodes
@ -114,6 +116,7 @@ Example:
#size-cells = <0>;
reg = <17 1>; /* MDIO address 17, switch 1 in tree */
mii-bus = <&mii_bus1>;
reset-gpios = <&gpio5 1 GPIO_ACTIVE_LOW>;
switch1port0: port@0 {
reg = <0>;

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@ -16,6 +16,7 @@
#include <linux/timer.h>
#include <linux/workqueue.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/phy.h>
#include <linux/phy_fixed.h>
#include <linux/ethtool.h>
@ -64,6 +65,13 @@ struct dsa_chip_data {
* NULL if there is only one switch chip.
*/
s8 *rtable;
/*
* A switch may have a GPIO line tied to its reset pin. Parse
* this from the device tree, and use it before performing
* switch soft reset.
*/
struct gpio_desc *reset;
};
struct dsa_platform_data {

View File

@ -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 @@ static int dsa_of_probe(struct device *dev)
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 @@ static int dsa_of_probe(struct device *dev)
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);