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linux/drivers/net/mdio/mdio-sun4i.c
Uwe Kleine-König efd8d90735 net: mdio: sun4i: Convert to platform remove callback returning void
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new() which already returns void. Eventually after all drivers
are converted, .remove_new() is renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-20 10:29:35 +01:00

179 lines
4.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Allwinner EMAC MDIO interface driver
*
* Copyright 2012-2013 Stefan Roese <sr@denx.de>
* Copyright 2013 Maxime Ripard <maxime.ripard@free-electrons.com>
*
* Based on the Linux driver provided by Allwinner:
* Copyright (C) 1997 Sten Wang
*/
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of_address.h>
#include <linux/of_mdio.h>
#include <linux/phy.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#define EMAC_MAC_MCMD_REG (0x00)
#define EMAC_MAC_MADR_REG (0x04)
#define EMAC_MAC_MWTD_REG (0x08)
#define EMAC_MAC_MRDD_REG (0x0c)
#define EMAC_MAC_MIND_REG (0x10)
#define EMAC_MAC_SSRR_REG (0x14)
#define MDIO_TIMEOUT (msecs_to_jiffies(100))
struct sun4i_mdio_data {
void __iomem *membase;
struct regulator *regulator;
};
static int sun4i_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
{
struct sun4i_mdio_data *data = bus->priv;
unsigned long timeout_jiffies;
int value;
/* issue the phy address and reg */
writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
/* pull up the phy io line */
writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
/* Wait read complete */
timeout_jiffies = jiffies + MDIO_TIMEOUT;
while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
if (time_is_before_jiffies(timeout_jiffies))
return -ETIMEDOUT;
msleep(1);
}
/* push down the phy io line */
writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
/* and read data */
value = readl(data->membase + EMAC_MAC_MRDD_REG);
return value;
}
static int sun4i_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
u16 value)
{
struct sun4i_mdio_data *data = bus->priv;
unsigned long timeout_jiffies;
/* issue the phy address and reg */
writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
/* pull up the phy io line */
writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
/* Wait read complete */
timeout_jiffies = jiffies + MDIO_TIMEOUT;
while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
if (time_is_before_jiffies(timeout_jiffies))
return -ETIMEDOUT;
msleep(1);
}
/* push down the phy io line */
writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
/* and write data */
writel(value, data->membase + EMAC_MAC_MWTD_REG);
return 0;
}
static int sun4i_mdio_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
struct mii_bus *bus;
struct sun4i_mdio_data *data;
int ret;
bus = mdiobus_alloc_size(sizeof(*data));
if (!bus)
return -ENOMEM;
bus->name = "sun4i_mii_bus";
bus->read = &sun4i_mdio_read;
bus->write = &sun4i_mdio_write;
snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
bus->parent = &pdev->dev;
data = bus->priv;
data->membase = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(data->membase)) {
ret = PTR_ERR(data->membase);
goto err_out_free_mdiobus;
}
data->regulator = devm_regulator_get(&pdev->dev, "phy");
if (IS_ERR(data->regulator)) {
if (PTR_ERR(data->regulator) == -EPROBE_DEFER) {
ret = -EPROBE_DEFER;
goto err_out_free_mdiobus;
}
dev_info(&pdev->dev, "no regulator found\n");
data->regulator = NULL;
} else {
ret = regulator_enable(data->regulator);
if (ret)
goto err_out_free_mdiobus;
}
ret = of_mdiobus_register(bus, np);
if (ret < 0)
goto err_out_disable_regulator;
platform_set_drvdata(pdev, bus);
return 0;
err_out_disable_regulator:
if (data->regulator)
regulator_disable(data->regulator);
err_out_free_mdiobus:
mdiobus_free(bus);
return ret;
}
static void sun4i_mdio_remove(struct platform_device *pdev)
{
struct mii_bus *bus = platform_get_drvdata(pdev);
struct sun4i_mdio_data *data = bus->priv;
mdiobus_unregister(bus);
if (data->regulator)
regulator_disable(data->regulator);
mdiobus_free(bus);
}
static const struct of_device_id sun4i_mdio_dt_ids[] = {
{ .compatible = "allwinner,sun4i-a10-mdio" },
/* Deprecated */
{ .compatible = "allwinner,sun4i-mdio" },
{ }
};
MODULE_DEVICE_TABLE(of, sun4i_mdio_dt_ids);
static struct platform_driver sun4i_mdio_driver = {
.probe = sun4i_mdio_probe,
.remove_new = sun4i_mdio_remove,
.driver = {
.name = "sun4i-mdio",
.of_match_table = sun4i_mdio_dt_ids,
},
};
module_platform_driver(sun4i_mdio_driver);
MODULE_DESCRIPTION("Allwinner EMAC MDIO interface driver");
MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
MODULE_LICENSE("GPL v2");