linux/drivers/net/phy/mdio-ipq4019.c
Robert Marko 466ed24fb2 net: phy: mdio: add IPQ4019 MDIO driver
This patch adds the driver for the MDIO interface
inside of Qualcomm IPQ40xx series SoC-s.

Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Luka Perkov <luka.perkov@sartura.hr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-30 12:11:14 -07:00

161 lines
3.8 KiB
C

// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/* Copyright (c) 2015, The Linux Foundation. All rights reserved. */
/* Copyright (c) 2020 Sartura Ltd. */
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/of_address.h>
#include <linux/of_mdio.h>
#include <linux/phy.h>
#include <linux/platform_device.h>
#define MDIO_ADDR_REG 0x44
#define MDIO_DATA_WRITE_REG 0x48
#define MDIO_DATA_READ_REG 0x4c
#define MDIO_CMD_REG 0x50
#define MDIO_CMD_ACCESS_BUSY BIT(16)
#define MDIO_CMD_ACCESS_START BIT(8)
#define MDIO_CMD_ACCESS_CODE_READ 0
#define MDIO_CMD_ACCESS_CODE_WRITE 1
#define ipq4019_MDIO_TIMEOUT 10000
#define ipq4019_MDIO_SLEEP 10
struct ipq4019_mdio_data {
void __iomem *membase;
};
static int ipq4019_mdio_wait_busy(struct mii_bus *bus)
{
struct ipq4019_mdio_data *priv = bus->priv;
unsigned int busy;
return readl_poll_timeout(priv->membase + MDIO_CMD_REG, busy,
(busy & MDIO_CMD_ACCESS_BUSY) == 0,
ipq4019_MDIO_SLEEP, ipq4019_MDIO_TIMEOUT);
}
static int ipq4019_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
{
struct ipq4019_mdio_data *priv = bus->priv;
unsigned int cmd;
/* Reject clause 45 */
if (regnum & MII_ADDR_C45)
return -EOPNOTSUPP;
if (ipq4019_mdio_wait_busy(bus))
return -ETIMEDOUT;
/* issue the phy address and reg */
writel((mii_id << 8) | regnum, priv->membase + MDIO_ADDR_REG);
cmd = MDIO_CMD_ACCESS_START | MDIO_CMD_ACCESS_CODE_READ;
/* issue read command */
writel(cmd, priv->membase + MDIO_CMD_REG);
/* Wait read complete */
if (ipq4019_mdio_wait_busy(bus))
return -ETIMEDOUT;
/* Read and return data */
return readl(priv->membase + MDIO_DATA_READ_REG);
}
static int ipq4019_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
u16 value)
{
struct ipq4019_mdio_data *priv = bus->priv;
unsigned int cmd;
/* Reject clause 45 */
if (regnum & MII_ADDR_C45)
return -EOPNOTSUPP;
if (ipq4019_mdio_wait_busy(bus))
return -ETIMEDOUT;
/* issue the phy address and reg */
writel((mii_id << 8) | regnum, priv->membase + MDIO_ADDR_REG);
/* issue write data */
writel(value, priv->membase + MDIO_DATA_WRITE_REG);
cmd = MDIO_CMD_ACCESS_START | MDIO_CMD_ACCESS_CODE_WRITE;
/* issue write command */
writel(cmd, priv->membase + MDIO_CMD_REG);
/* Wait write complete */
if (ipq4019_mdio_wait_busy(bus))
return -ETIMEDOUT;
return 0;
}
static int ipq4019_mdio_probe(struct platform_device *pdev)
{
struct ipq4019_mdio_data *priv;
struct mii_bus *bus;
int ret;
bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));
if (!bus)
return -ENOMEM;
priv = bus->priv;
priv->membase = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(priv->membase))
return PTR_ERR(priv->membase);
bus->name = "ipq4019_mdio";
bus->read = ipq4019_mdio_read;
bus->write = ipq4019_mdio_write;
bus->parent = &pdev->dev;
snprintf(bus->id, MII_BUS_ID_SIZE, "%s%d", pdev->name, pdev->id);
ret = of_mdiobus_register(bus, pdev->dev.of_node);
if (ret) {
dev_err(&pdev->dev, "Cannot register MDIO bus!\n");
return ret;
}
platform_set_drvdata(pdev, bus);
return 0;
}
static int ipq4019_mdio_remove(struct platform_device *pdev)
{
struct mii_bus *bus = platform_get_drvdata(pdev);
mdiobus_unregister(bus);
return 0;
}
static const struct of_device_id ipq4019_mdio_dt_ids[] = {
{ .compatible = "qcom,ipq4019-mdio" },
{ }
};
MODULE_DEVICE_TABLE(of, ipq4019_mdio_dt_ids);
static struct platform_driver ipq4019_mdio_driver = {
.probe = ipq4019_mdio_probe,
.remove = ipq4019_mdio_remove,
.driver = {
.name = "ipq4019-mdio",
.of_match_table = ipq4019_mdio_dt_ids,
},
};
module_platform_driver(ipq4019_mdio_driver);
MODULE_DESCRIPTION("ipq4019 MDIO interface driver");
MODULE_AUTHOR("Qualcomm Atheros");
MODULE_LICENSE("Dual BSD/GPL");