129 lines
2.7 KiB
C
129 lines
2.7 KiB
C
/*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*
|
|
* Copyright (C) 2011, 2012 Cavium, Inc.
|
|
*/
|
|
|
|
#include <linux/platform_device.h>
|
|
#include <linux/device.h>
|
|
#include <linux/of_mdio.h>
|
|
#include <linux/module.h>
|
|
#include <linux/phy.h>
|
|
#include <linux/mdio-mux.h>
|
|
#include <linux/of_gpio.h>
|
|
|
|
#define DRV_VERSION "1.1"
|
|
#define DRV_DESCRIPTION "GPIO controlled MDIO bus multiplexer driver"
|
|
|
|
#define MDIO_MUX_GPIO_MAX_BITS 8
|
|
|
|
struct mdio_mux_gpio_state {
|
|
struct gpio_desc *gpio[MDIO_MUX_GPIO_MAX_BITS];
|
|
unsigned int num_gpios;
|
|
void *mux_handle;
|
|
};
|
|
|
|
static int mdio_mux_gpio_switch_fn(int current_child, int desired_child,
|
|
void *data)
|
|
{
|
|
int values[MDIO_MUX_GPIO_MAX_BITS];
|
|
unsigned int n;
|
|
struct mdio_mux_gpio_state *s = data;
|
|
|
|
if (current_child == desired_child)
|
|
return 0;
|
|
|
|
for (n = 0; n < s->num_gpios; n++) {
|
|
values[n] = (desired_child >> n) & 1;
|
|
}
|
|
gpiod_set_array_cansleep(s->num_gpios, s->gpio, values);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mdio_mux_gpio_probe(struct platform_device *pdev)
|
|
{
|
|
struct mdio_mux_gpio_state *s;
|
|
int num_gpios;
|
|
unsigned int n;
|
|
int r;
|
|
|
|
if (!pdev->dev.of_node)
|
|
return -ENODEV;
|
|
|
|
num_gpios = of_gpio_count(pdev->dev.of_node);
|
|
if (num_gpios <= 0 || num_gpios > MDIO_MUX_GPIO_MAX_BITS)
|
|
return -ENODEV;
|
|
|
|
s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
|
|
if (!s)
|
|
return -ENOMEM;
|
|
|
|
s->num_gpios = num_gpios;
|
|
|
|
for (n = 0; n < num_gpios; ) {
|
|
struct gpio_desc *gpio = gpiod_get_index(&pdev->dev, NULL, n,
|
|
GPIOD_OUT_LOW);
|
|
if (IS_ERR(gpio)) {
|
|
r = PTR_ERR(gpio);
|
|
goto err;
|
|
}
|
|
s->gpio[n] = gpio;
|
|
n++;
|
|
}
|
|
|
|
r = mdio_mux_init(&pdev->dev,
|
|
mdio_mux_gpio_switch_fn, &s->mux_handle, s);
|
|
|
|
if (r == 0) {
|
|
pdev->dev.platform_data = s;
|
|
return 0;
|
|
}
|
|
err:
|
|
while (n) {
|
|
n--;
|
|
gpiod_put(s->gpio[n]);
|
|
}
|
|
return r;
|
|
}
|
|
|
|
static int mdio_mux_gpio_remove(struct platform_device *pdev)
|
|
{
|
|
unsigned int n;
|
|
struct mdio_mux_gpio_state *s = dev_get_platdata(&pdev->dev);
|
|
mdio_mux_uninit(s->mux_handle);
|
|
for (n = 0; n < s->num_gpios; n++)
|
|
gpiod_put(s->gpio[n]);
|
|
return 0;
|
|
}
|
|
|
|
static struct of_device_id mdio_mux_gpio_match[] = {
|
|
{
|
|
.compatible = "mdio-mux-gpio",
|
|
},
|
|
{
|
|
/* Legacy compatible property. */
|
|
.compatible = "cavium,mdio-mux-sn74cbtlv3253",
|
|
},
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, mdio_mux_gpio_match);
|
|
|
|
static struct platform_driver mdio_mux_gpio_driver = {
|
|
.driver = {
|
|
.name = "mdio-mux-gpio",
|
|
.of_match_table = mdio_mux_gpio_match,
|
|
},
|
|
.probe = mdio_mux_gpio_probe,
|
|
.remove = mdio_mux_gpio_remove,
|
|
};
|
|
|
|
module_platform_driver(mdio_mux_gpio_driver);
|
|
|
|
MODULE_DESCRIPTION(DRV_DESCRIPTION);
|
|
MODULE_VERSION(DRV_VERSION);
|
|
MODULE_AUTHOR("David Daney");
|
|
MODULE_LICENSE("GPL");
|