linux-stable/drivers/net/phy/mdio-mux-gpio.c
Pramod Kumar f20e6657a8 mdio: mux: Enhanced MDIO mux framework for integrated multiplexers
An integrated multiplexer uses same address space for
"muxed bus selection" and "generation of mdio transaction"
hence its good to register parent bus from mux driver.

Hence added a mechanism where mux driver could register a
parent bus and pass it down to framework via mdio_mux_init api.

Signed-off-by: Pramod Kumar <pramod.kumar@broadcom.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-10 23:24:53 -07:00

103 lines
2.3 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/gpio/consumer.h>
#define DRV_VERSION "1.1"
#define DRV_DESCRIPTION "GPIO controlled MDIO bus multiplexer driver"
struct mdio_mux_gpio_state {
struct gpio_descs *gpios;
void *mux_handle;
};
static int mdio_mux_gpio_switch_fn(int current_child, int desired_child,
void *data)
{
struct mdio_mux_gpio_state *s = data;
int values[s->gpios->ndescs];
unsigned int n;
if (current_child == desired_child)
return 0;
for (n = 0; n < s->gpios->ndescs; n++)
values[n] = (desired_child >> n) & 1;
gpiod_set_array_value_cansleep(s->gpios->ndescs, s->gpios->desc,
values);
return 0;
}
static int mdio_mux_gpio_probe(struct platform_device *pdev)
{
struct mdio_mux_gpio_state *s;
int r;
s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
if (!s)
return -ENOMEM;
s->gpios = gpiod_get_array(&pdev->dev, NULL, GPIOD_OUT_LOW);
if (IS_ERR(s->gpios))
return PTR_ERR(s->gpios);
r = mdio_mux_init(&pdev->dev,
mdio_mux_gpio_switch_fn, &s->mux_handle, s, NULL);
if (r != 0) {
gpiod_put_array(s->gpios);
return r;
}
pdev->dev.platform_data = s;
return 0;
}
static int mdio_mux_gpio_remove(struct platform_device *pdev)
{
struct mdio_mux_gpio_state *s = dev_get_platdata(&pdev->dev);
mdio_mux_uninit(s->mux_handle);
gpiod_put_array(s->gpios);
return 0;
}
static const 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");