linux/drivers/net/mdio/mdio-mux-meson-gxl.c
Uwe Kleine-König a2879f755e net: mdio: mux-meson-gxl: 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>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-20 10:29:34 +01:00

163 lines
4.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2022 Baylibre, SAS.
* Author: Jerome Brunet <jbrunet@baylibre.com>
*/
#include <linux/bitfield.h>
#include <linux/delay.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/mdio-mux.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#define ETH_REG2 0x0
#define REG2_PHYID GENMASK(21, 0)
#define EPHY_GXL_ID 0x110181
#define REG2_LEDACT GENMASK(23, 22)
#define REG2_LEDLINK GENMASK(25, 24)
#define REG2_DIV4SEL BIT(27)
#define REG2_ADCBYPASS BIT(30)
#define REG2_CLKINSEL BIT(31)
#define ETH_REG3 0x4
#define REG3_ENH BIT(3)
#define REG3_CFGMODE GENMASK(6, 4)
#define REG3_AUTOMDIX BIT(7)
#define REG3_PHYADDR GENMASK(12, 8)
#define REG3_PWRUPRST BIT(21)
#define REG3_PWRDOWN BIT(22)
#define REG3_LEDPOL BIT(23)
#define REG3_PHYMDI BIT(26)
#define REG3_CLKINEN BIT(29)
#define REG3_PHYIP BIT(30)
#define REG3_PHYEN BIT(31)
#define ETH_REG4 0x8
#define REG4_PWRUPRSTSIG BIT(0)
#define MESON_GXL_MDIO_EXTERNAL_ID 0
#define MESON_GXL_MDIO_INTERNAL_ID 1
struct gxl_mdio_mux {
void __iomem *regs;
void *mux_handle;
};
static void gxl_enable_internal_mdio(struct gxl_mdio_mux *priv)
{
u32 val;
/* Setup the internal phy */
val = (REG3_ENH |
FIELD_PREP(REG3_CFGMODE, 0x7) |
REG3_AUTOMDIX |
FIELD_PREP(REG3_PHYADDR, 8) |
REG3_LEDPOL |
REG3_PHYMDI |
REG3_CLKINEN |
REG3_PHYIP);
writel(REG4_PWRUPRSTSIG, priv->regs + ETH_REG4);
writel(val, priv->regs + ETH_REG3);
mdelay(10);
/* NOTE: The HW kept the phy id configurable at runtime.
* The id below is arbitrary. It is the one used in the vendor code.
* The only constraint is that it must match the one in
* drivers/net/phy/meson-gxl.c to properly match the PHY.
*/
writel(FIELD_PREP(REG2_PHYID, EPHY_GXL_ID),
priv->regs + ETH_REG2);
/* Enable the internal phy */
val |= REG3_PHYEN;
writel(val, priv->regs + ETH_REG3);
writel(0, priv->regs + ETH_REG4);
/* The phy needs a bit of time to power up */
mdelay(10);
}
static void gxl_enable_external_mdio(struct gxl_mdio_mux *priv)
{
/* Reset the mdio bus mux to the external phy */
writel(0, priv->regs + ETH_REG3);
}
static int gxl_mdio_switch_fn(int current_child, int desired_child,
void *data)
{
struct gxl_mdio_mux *priv = dev_get_drvdata(data);
if (current_child == desired_child)
return 0;
switch (desired_child) {
case MESON_GXL_MDIO_EXTERNAL_ID:
gxl_enable_external_mdio(priv);
break;
case MESON_GXL_MDIO_INTERNAL_ID:
gxl_enable_internal_mdio(priv);
break;
default:
return -EINVAL;
}
return 0;
}
static const struct of_device_id gxl_mdio_mux_match[] = {
{ .compatible = "amlogic,gxl-mdio-mux", },
{},
};
MODULE_DEVICE_TABLE(of, gxl_mdio_mux_match);
static int gxl_mdio_mux_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct gxl_mdio_mux *priv;
struct clk *rclk;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
platform_set_drvdata(pdev, priv);
priv->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(priv->regs))
return PTR_ERR(priv->regs);
rclk = devm_clk_get_enabled(dev, "ref");
if (IS_ERR(rclk))
return dev_err_probe(dev, PTR_ERR(rclk),
"failed to get reference clock\n");
ret = mdio_mux_init(dev, dev->of_node, gxl_mdio_switch_fn,
&priv->mux_handle, dev, NULL);
if (ret)
dev_err_probe(dev, ret, "mdio multiplexer init failed\n");
return ret;
}
static void gxl_mdio_mux_remove(struct platform_device *pdev)
{
struct gxl_mdio_mux *priv = platform_get_drvdata(pdev);
mdio_mux_uninit(priv->mux_handle);
}
static struct platform_driver gxl_mdio_mux_driver = {
.probe = gxl_mdio_mux_probe,
.remove_new = gxl_mdio_mux_remove,
.driver = {
.name = "gxl-mdio-mux",
.of_match_table = gxl_mdio_mux_match,
},
};
module_platform_driver(gxl_mdio_mux_driver);
MODULE_DESCRIPTION("Amlogic GXL MDIO multiplexer driver");
MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
MODULE_LICENSE("GPL");