Release 4.14 arch/powerpc/platforms/pasemi/gpio_mdio.c

Directory: arch/powerpc/platforms/pasemi
/*
 * Copyright (C) 2006-2007 PA Semi, Inc
 *
 * Author: Olof Johansson, PA Semi
 *
 * Maintained by: Olof Johansson <olof@lixom.net>
 *
 * Based on drivers/net/fs_enet/mii-bitbang.c.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include <linux/io.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/phy.h>
#include <linux/of_address.h>
#include <linux/of_mdio.h>
#include <linux/of_platform.h>


#define DELAY 1


static void __iomem *gpio_regs;


struct gpio_priv {
	
int mdc_pin;
	
int mdio_pin;
};


#define MDC_PIN(bus)	(((struct gpio_priv *)bus->priv)->mdc_pin)

#define MDIO_PIN(bus)	(((struct gpio_priv *)bus->priv)->mdio_pin)



static inline void mdio_lo(struct mii_bus *bus)
{
	out_le32(gpio_regs+0x10, 1 << MDIO_PIN(bus));
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 26 100.00% 1 100.00%
Total 26 100.00% 1 100.00%



static inline void mdio_hi(struct mii_bus *bus)
{
	out_le32(gpio_regs, 1 << MDIO_PIN(bus));
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 24 100.00% 1 100.00%
Total 24 100.00% 1 100.00%



static inline void mdc_lo(struct mii_bus *bus)
{
	out_le32(gpio_regs+0x10, 1 << MDC_PIN(bus));
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 26 100.00% 1 100.00%
Total 26 100.00% 1 100.00%



static inline void mdc_hi(struct mii_bus *bus)
{
	out_le32(gpio_regs, 1 << MDC_PIN(bus));
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 24 100.00% 1 100.00%
Total 24 100.00% 1 100.00%



static inline void mdio_active(struct mii_bus *bus)
{
	out_le32(gpio_regs+0x20, (1 << MDC_PIN(bus)) | (1 << MDIO_PIN(bus)));
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 37 100.00% 1 100.00%
Total 37 100.00% 1 100.00%



static inline void mdio_tristate(struct mii_bus *bus)
{
	out_le32(gpio_regs+0x30, (1 << MDIO_PIN(bus)));
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 28 100.00% 1 100.00%
Total 28 100.00% 1 100.00%



static inline int mdio_read(struct mii_bus *bus)
{
	return !!(in_le32(gpio_regs+0x40) & (1 << MDIO_PIN(bus)));
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 33 100.00% 1 100.00%
Total 33 100.00% 1 100.00%



static void clock_out(struct mii_bus *bus, int bit)
{
	if (bit)
		mdio_hi(bus);
	else
		mdio_lo(bus);
	udelay(DELAY);
	mdc_hi(bus);
	udelay(DELAY);
	mdc_lo(bus);
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 49 100.00% 1 100.00%
Total 49 100.00% 1 100.00%

/* Utility to send the preamble, address, and register (common to read and write). */


static void bitbang_pre(struct mii_bus *bus, int read, u8 addr, u8 reg)
{
	int i;

	/* CFE uses a really long preamble (40 bits). We'll do the same. */
	mdio_active(bus);
	for (i = 0; i < 40; i++) {
		clock_out(bus, 1);
	}

	/* send the start bit (01) and the read opcode (10) or write (10) */
	clock_out(bus, 0);
	clock_out(bus, 1);

	clock_out(bus, read);
	clock_out(bus, !read);

	/* send the PHY address */
	for (i = 0; i < 5; i++) {
		clock_out(bus, (addr & 0x10) != 0);
		addr <<= 1;
	}

	/* send the register address */
	for (i = 0; i < 5; i++) {
		clock_out(bus, (reg & 0x10) != 0);
		reg <<= 1;
	}
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 147 100.00% 1 100.00%
Total 147 100.00% 1 100.00%



static int gpio_mdio_read(struct mii_bus *bus, int phy_id, int location)
{
	u16 rdreg;
	int ret, i;
	u8 addr = phy_id & 0xff;
	u8 reg = location & 0xff;

	bitbang_pre(bus, 1, addr, reg);

	/* tri-state our MDIO I/O pin so we can read */
	mdio_tristate(bus);
	udelay(DELAY);
	mdc_hi(bus);
	udelay(DELAY);
	mdc_lo(bus);

	/* read 16 bits of register data, MSB first */
	rdreg = 0;
	for (i = 0; i < 16; i++) {
		mdc_lo(bus);
		udelay(DELAY);
		mdc_hi(bus);
		udelay(DELAY);
		mdc_lo(bus);
		udelay(DELAY);
		rdreg <<= 1;
		rdreg |= mdio_read(bus);
	}

	mdc_hi(bus);
	udelay(DELAY);
	mdc_lo(bus);
	udelay(DELAY);

	ret = rdreg;

	return ret;
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 164 100.00% 1 100.00%
Total 164 100.00% 1 100.00%



static int gpio_mdio_write(struct mii_bus *bus, int phy_id, int location, u16 val)
{
	int i;

	u8 addr = phy_id & 0xff;
	u8 reg = location & 0xff;
	u16 value = val & 0xffff;

	bitbang_pre(bus, 0, addr, reg);

	/* send the turnaround (10) */
	mdc_lo(bus);
	mdio_hi(bus);
	udelay(DELAY);
	mdc_hi(bus);
	udelay(DELAY);
	mdc_lo(bus);
	mdio_lo(bus);
	udelay(DELAY);
	mdc_hi(bus);
	udelay(DELAY);

	/* write 16 bits of register data, MSB first */
	for (i = 0; i < 16; i++) {
		mdc_lo(bus);
		if (value & 0x8000)
			mdio_hi(bus);
		else
			mdio_lo(bus);
		udelay(DELAY);
		mdc_hi(bus);
		udelay(DELAY);
		value <<= 1;
	}

	/*
         * Tri-state the MDIO line.
         */
	mdio_tristate(bus);
	mdc_lo(bus);
	udelay(DELAY);
	mdc_hi(bus);
	udelay(DELAY);
	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 192 100.00% 1 100.00%
Total 192 100.00% 1 100.00%



static int gpio_mdio_reset(struct mii_bus *bus)
{
	/*nothing here - dunno how to reset it*/
	return 0;
}


Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 15 100.00% 1 100.00%
Total 15 100.00% 1 100.00%



static int gpio_mdio_probe(struct platform_device *ofdev)
{
	struct device *dev = &ofdev->dev;
	struct device_node *np = ofdev->dev.of_node;
	struct mii_bus *new_bus;
	struct gpio_priv *priv;
	const unsigned int *prop;
	int err;

	err = -ENOMEM;
	priv = kzalloc(sizeof(struct gpio_priv), GFP_KERNEL);
	if (!priv)
		goto out;

	new_bus = mdiobus_alloc();

	if (!new_bus)
		goto out_free_priv;

	new_bus->name = "pasemi gpio mdio bus";
	new_bus->read = &gpio_mdio_read;
	new_bus->write = &gpio_mdio_write;
	new_bus->reset = &gpio_mdio_reset;

	prop = of_get_property(np, "reg", NULL);
	snprintf(new_bus->id, MII_BUS_ID_SIZE, "%x", *prop);
	new_bus->priv = priv;

	prop = of_get_property(np, "mdc-pin", NULL);
	priv->mdc_pin = *prop;

	prop = of_get_property(np, "mdio-pin", NULL);
	priv->mdio_pin = *prop;

	new_bus->parent = dev;
	dev_set_drvdata(dev, new_bus);

	err = of_mdiobus_register(new_bus, np);

	if (err != 0) {
		printk(KERN_ERR "%s: Cannot register as MDIO bus, err %d\n",
				new_bus->name, err);
		goto out_free_irq;
	}

	return 0;

out_free_irq:
	kfree(new_bus);
out_free_priv:
	kfree(priv);
out:
	return err;
}


Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 230 91.63% 2 22.22%
Andy Fleming 8 3.19% 1 11.11%
Grant C. Likely 7 2.79% 3 33.33%
Stephen Rothwell 3 1.20% 1 11.11%
Lennert Buytenhek 3 1.20% 2 22.22%
Total 251 100.00% 9 100.00%



static int gpio_mdio_remove(struct platform_device *dev)
{
	struct mii_bus *bus = dev_get_drvdata(&dev->dev);

	mdiobus_unregister(bus);

	dev_set_drvdata(&dev->dev, NULL);

	kfree(bus->priv);
	bus->priv = NULL;
	mdiobus_free(bus);

	return 0;
}

Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 58 96.67% 1 33.33%
Lennert Buytenhek 1 1.67% 1 33.33%
Grant C. Likely 1 1.67% 1 33.33%
Total 60 100.00% 3 100.00%


static const struct of_device_id gpio_mdio_match[] =
{
	{
		.compatible      = "gpio-mdio",
        },
	{},
};
MODULE_DEVICE_TABLE(of, gpio_mdio_match);


static struct platform_driver gpio_mdio_driver =
{
	.probe		= gpio_mdio_probe,
	.remove		= gpio_mdio_remove,
	.driver = {
		.name = "gpio-mdio-bitbang",
		.of_match_table = gpio_mdio_match,
        },
};



static int gpio_mdio_init(void)
{
	struct device_node *np;

	np = of_find_compatible_node(NULL, NULL, "1682m-gpio");
	if (!np)
		np = of_find_compatible_node(NULL, NULL,
					     "pasemi,pwrficient-gpio");
	if (!np)
		return -ENODEV;
	gpio_regs = of_iomap(np, 0);
	of_node_put(np);

	if (!gpio_regs)
		return -ENODEV;

	return platform_driver_register(&gpio_mdio_driver);
}
Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 77 97.47% 3 60.00%
Daniel Axtens 1 1.27% 1 20.00%
Grant C. Likely 1 1.27% 1 20.00%
Total 79 100.00% 5 100.00%


module_init(gpio_mdio_init);



static void gpio_mdio_exit(void)
{
	platform_driver_unregister(&gpio_mdio_driver);
	if (gpio_regs)
		iounmap(gpio_regs);
}
Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 21 91.30% 2 50.00%
Daniel Axtens 1 4.35% 1 25.00%
Grant C. Likely 1 4.35% 1 25.00%
Total 23 100.00% 4 100.00%


module_exit(gpio_mdio_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Olof Johansson <olof@lixom.net>");
MODULE_DESCRIPTION("Driver for MDIO over GPIO on PA Semi PWRficient-based boards");
Overall Contributors
Person Tokens Prop Commits CommitProp
Olof Johansson 1281 96.10% 4 21.05%
Grant C. Likely 17 1.28% 5 26.32%
Stephen Rothwell 13 0.98% 2 10.53%
Andy Fleming 8 0.60% 1 5.26%
Lennert Buytenhek 4 0.30% 2 10.53%
Tejun Heo 3 0.23% 1 5.26%
Rob Herring 3 0.23% 1 5.26%
Daniel Axtens 2 0.15% 1 5.26%
Jon Loeliger 1 0.08% 1 5.26%
Uwe Kleine-König 1 0.08% 1 5.26%
Total 1333 100.00% 19 100.00%
Directory: arch/powerpc/platforms/pasemi

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.
Person	Tokens	Prop	Commits	CommitProp
Olof Johansson	26	100.00%	1	100.00%
Total	26	100.00%	1	100.00%
cregit-Linux how code gets into the kernel

Release 4.14 arch/powerpc/platforms/pasemi/gpio_mdio.c

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Overall Contributors
