Commit a5edeccb authored by Laurent Pinchart's avatar Laurent Pinchart Committed by Jeff Garzik

net: OpenFirmware GPIO based MDIO bitbang driver

This patch adds an MDIO bitbang driver that uses the GPIO library and its
OF bindings to access the bus I/Os.
Signed-off-by: default avatarLaurent Pinchart <laurentp@cse-semaphore.com>
Signed-off-by: default avatarJeff Garzik <jgarzik@redhat.com>
parent 62c78329
......@@ -58,6 +58,7 @@ Table of Contents
o) Xilinx IP cores
p) Freescale Synchronous Serial Interface
q) USB EHCI controllers
r) MDIO on GPIOs
VII - Marvell Discovery mv64[345]6x System Controller chips
1) The /system-controller node
......@@ -2870,6 +2871,26 @@ platforms are moved over to use the flattened-device-tree model.
reg = <0xe8000000 32>;
};
r) MDIO on GPIOs
Currently defined compatibles:
- virtual,gpio-mdio
MDC and MDIO lines connected to GPIO controllers are listed in the
gpios property as described in section VIII.1 in the following order:
MDC, MDIO.
Example:
mdio {
compatible = "virtual,mdio-gpio";
#address-cells = <1>;
#size-cells = <0>;
gpios = <&qe_pio_a 11
&qe_pio_c 6>;
};
VII - Marvell Discovery mv64[345]6x System Controller chips
===========================================================
......
......@@ -84,4 +84,10 @@ config MDIO_BITBANG
If in doubt, say N.
config MDIO_OF_GPIO
tristate "Support for GPIO lib-based bitbanged MDIO buses"
depends on MDIO_BITBANG && OF_GPIO
---help---
Supports GPIO lib-based MDIO busses.
endif # PHYLIB
......@@ -15,3 +15,4 @@ obj-$(CONFIG_ICPLUS_PHY) += icplus.o
obj-$(CONFIG_REALTEK_PHY) += realtek.o
obj-$(CONFIG_FIXED_PHY) += fixed.o
obj-$(CONFIG_MDIO_BITBANG) += mdio-bitbang.o
obj-$(CONFIG_MDIO_OF_GPIO) += mdio-ofgpio.o
/*
* OpenFirmware GPIO based MDIO bitbang driver.
*
* Copyright (c) 2008 CSE Semaphore Belgium.
* by Laurent Pinchart <laurentp@cse-semaphore.com>
*
* Based on earlier work by
*
* Copyright (c) 2003 Intracom S.A.
* by Pantelis Antoniou <panto@intracom.gr>
*
* 2005 (c) MontaVista Software, Inc.
* Vitaly Bordug <vbordug@ru.mvista.com>
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/mdio-bitbang.h>
#include <linux/of_gpio.h>
#include <linux/of_platform.h>
struct mdio_gpio_info {
struct mdiobb_ctrl ctrl;
int mdc, mdio;
};
static void mdio_dir(struct mdiobb_ctrl *ctrl, int dir)
{
struct mdio_gpio_info *bitbang =
container_of(ctrl, struct mdio_gpio_info, ctrl);
if (dir)
gpio_direction_output(bitbang->mdio, 1);
else
gpio_direction_input(bitbang->mdio);
}
static int mdio_read(struct mdiobb_ctrl *ctrl)
{
struct mdio_gpio_info *bitbang =
container_of(ctrl, struct mdio_gpio_info, ctrl);
return gpio_get_value(bitbang->mdio);
}
static void mdio(struct mdiobb_ctrl *ctrl, int what)
{
struct mdio_gpio_info *bitbang =
container_of(ctrl, struct mdio_gpio_info, ctrl);
gpio_set_value(bitbang->mdio, what);
}
static void mdc(struct mdiobb_ctrl *ctrl, int what)
{
struct mdio_gpio_info *bitbang =
container_of(ctrl, struct mdio_gpio_info, ctrl);
gpio_set_value(bitbang->mdc, what);
}
static struct mdiobb_ops mdio_gpio_ops = {
.owner = THIS_MODULE,
.set_mdc = mdc,
.set_mdio_dir = mdio_dir,
.set_mdio_data = mdio,
.get_mdio_data = mdio_read,
};
static int __devinit mdio_ofgpio_bitbang_init(struct mii_bus *bus,
struct device_node *np)
{
struct mdio_gpio_info *bitbang = bus->priv;
bitbang->mdc = of_get_gpio(np, 0);
bitbang->mdio = of_get_gpio(np, 1);
if (bitbang->mdc < 0 || bitbang->mdio < 0)
return -ENODEV;
snprintf(bus->id, MII_BUS_ID_SIZE, "%x", bitbang->mdc);
return 0;
}
static void __devinit add_phy(struct mii_bus *bus, struct device_node *np)
{
const u32 *data;
int len, id, irq;
data = of_get_property(np, "reg", &len);
if (!data || len != 4)
return;
id = *data;
bus->phy_mask &= ~(1 << id);
irq = of_irq_to_resource(np, 0, NULL);
if (irq != NO_IRQ)
bus->irq[id] = irq;
}
static int __devinit mdio_ofgpio_probe(struct of_device *ofdev,
const struct of_device_id *match)
{
struct device_node *np = NULL;
struct mii_bus *new_bus;
struct mdio_gpio_info *bitbang;
int ret = -ENOMEM;
int i;
bitbang = kzalloc(sizeof(struct mdio_gpio_info), GFP_KERNEL);
if (!bitbang)
goto out;
bitbang->ctrl.ops = &mdio_gpio_ops;
new_bus = alloc_mdio_bitbang(&bitbang->ctrl);
if (!new_bus)
goto out_free_priv;
new_bus->name = "GPIO Bitbanged MII",
ret = mdio_ofgpio_bitbang_init(new_bus, ofdev->node);
if (ret)
goto out_free_bus;
new_bus->phy_mask = ~0;
new_bus->irq = kmalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
if (!new_bus->irq)
goto out_free_bus;
for (i = 0; i < PHY_MAX_ADDR; i++)
new_bus->irq[i] = -1;
while ((np = of_get_next_child(ofdev->node, np)))
if (!strcmp(np->type, "ethernet-phy"))
add_phy(new_bus, np);
new_bus->dev = &ofdev->dev;
dev_set_drvdata(&ofdev->dev, new_bus);
ret = mdiobus_register(new_bus);
if (ret)
goto out_free_irqs;
return 0;
out_free_irqs:
dev_set_drvdata(&ofdev->dev, NULL);
kfree(new_bus->irq);
out_free_bus:
kfree(new_bus);
out_free_priv:
free_mdio_bitbang(new_bus);
out:
return ret;
}
static int mdio_ofgpio_remove(struct of_device *ofdev)
{
struct mii_bus *bus = dev_get_drvdata(&ofdev->dev);
struct mdio_gpio_info *bitbang = bus->priv;
mdiobus_unregister(bus);
free_mdio_bitbang(bus);
dev_set_drvdata(&ofdev->dev, NULL);
kfree(bus->irq);
kfree(bitbang);
kfree(bus);
return 0;
}
static struct of_device_id mdio_ofgpio_match[] = {
{
.compatible = "virtual,mdio-gpio",
},
{},
};
static struct of_platform_driver mdio_ofgpio_driver = {
.name = "mdio-gpio",
.match_table = mdio_ofgpio_match,
.probe = mdio_ofgpio_probe,
.remove = mdio_ofgpio_remove,
};
static int mdio_ofgpio_init(void)
{
return of_register_platform_driver(&mdio_ofgpio_driver);
}
static void mdio_ofgpio_exit(void)
{
of_unregister_platform_driver(&mdio_ofgpio_driver);
}
module_init(mdio_ofgpio_init);
module_exit(mdio_ofgpio_exit);
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