drivers/net/ethernet/freescale/enetc/enetc_mdio.c

Source file repositories/reference/linux-study-clean/drivers/net/ethernet/freescale/enetc/enetc_mdio.c

File Facts

System
Linux kernel
Corpus path
drivers/net/ethernet/freescale/enetc/enetc_mdio.c
Extension
.c
Size
5838 bytes
Lines
237
Domain
Driver Families
Bucket
drivers/net
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
/* Copyright 2019 NXP */

#include <linux/fsl/enetc_mdio.h>
#include <linux/mdio.h>
#include <linux/of_mdio.h>
#include <linux/iopoll.h>
#include <linux/of.h>

#include "enetc_pf.h"

#define	ENETC_MDIO_CFG	0x0	/* MDIO configuration and status */
#define	ENETC_MDIO_CTL	0x4	/* MDIO control */
#define	ENETC_MDIO_DATA	0x8	/* MDIO data */
#define	ENETC_MDIO_ADDR	0xc	/* MDIO address */

#define MDIO_CFG_CLKDIV(x)	((((x) >> 1) & 0xff) << 8)
#define MDIO_CFG_BSY		BIT(0)
#define MDIO_CFG_RD_ER		BIT(1)
#define MDIO_CFG_HOLD(x)	(((x) << 2) & GENMASK(4, 2))
#define MDIO_CFG_ENC45		BIT(6)
 /* external MDIO only - driven on neg MDC edge */
#define MDIO_CFG_NEG		BIT(23)

#define ENETC_EMDIO_CFG \
	(MDIO_CFG_HOLD(2) | \
	 MDIO_CFG_CLKDIV(258) | \
	 MDIO_CFG_NEG)

#define MDIO_CTL_DEV_ADDR(x)	((x) & 0x1f)
#define MDIO_CTL_PORT_ADDR(x)	(((x) & 0x1f) << 5)
#define MDIO_CTL_READ		BIT(15)

static inline u32 enetc_mdio_rd(struct enetc_mdio_priv *mdio_priv, int off)
{
	return enetc_port_rd_mdio(mdio_priv->hw, mdio_priv->mdio_base + off);
}

static inline void enetc_mdio_wr(struct enetc_mdio_priv *mdio_priv, int off,
				 u32 val)
{
	enetc_port_wr_mdio(mdio_priv->hw, mdio_priv->mdio_base + off, val);
}

static bool enetc_mdio_is_busy(struct enetc_mdio_priv *mdio_priv)
{
	return enetc_mdio_rd(mdio_priv, ENETC_MDIO_CFG) & MDIO_CFG_BSY;
}

static int enetc_mdio_wait_complete(struct enetc_mdio_priv *mdio_priv)
{
	bool is_busy;

	return readx_poll_timeout(enetc_mdio_is_busy, mdio_priv,
				  is_busy, !is_busy, 10, 10 * 1000);
}

int enetc_mdio_write_c22(struct mii_bus *bus, int phy_id, int regnum,
			 u16 value)
{
	struct enetc_mdio_priv *mdio_priv = bus->priv;
	u32 mdio_ctl, mdio_cfg;
	u16 dev_addr;
	int ret;

	mdio_cfg = ENETC_EMDIO_CFG;
	dev_addr = regnum & 0x1f;
	mdio_cfg &= ~MDIO_CFG_ENC45;

	enetc_mdio_wr(mdio_priv, ENETC_MDIO_CFG, mdio_cfg);

	ret = enetc_mdio_wait_complete(mdio_priv);
	if (ret)
		return ret;

	/* set port and dev addr */
	mdio_ctl = MDIO_CTL_PORT_ADDR(phy_id) | MDIO_CTL_DEV_ADDR(dev_addr);
	enetc_mdio_wr(mdio_priv, ENETC_MDIO_CTL, mdio_ctl);

	/* write the value */
	enetc_mdio_wr(mdio_priv, ENETC_MDIO_DATA, value);

	ret = enetc_mdio_wait_complete(mdio_priv);
	if (ret)
		return ret;

	return 0;
}
EXPORT_SYMBOL_GPL(enetc_mdio_write_c22);

Annotation

Implementation Notes