drivers/net/mdio/mdio-ipq8064.c

Source file repositories/reference/linux-study-clean/drivers/net/mdio/mdio-ipq8064.c

File Facts

System
Linux kernel
Corpus path
drivers/net/mdio/mdio-ipq8064.c
Extension
.c
Size
4559 bytes
Lines
178
Domain
Driver Families
Bucket
drivers/net
Inferred role
Driver Families: implementation source
Status
source 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

struct ipq8064_mdio {
	struct regmap *base; /* NSS_GMAC0_BASE */
};

static int
ipq8064_mdio_wait_busy(struct ipq8064_mdio *priv)
{
	u32 busy;

	return regmap_read_poll_timeout(priv->base, MII_ADDR_REG_ADDR, busy,
					!(busy & MII_BUSY), MII_MDIO_DELAY_USEC,
					MII_MDIO_RETRY_MSEC * USEC_PER_MSEC);
}

static int
ipq8064_mdio_read(struct mii_bus *bus, int phy_addr, int reg_offset)
{
	u32 miiaddr = MII_BUSY | MII_CLKRANGE_250_300M;
	struct ipq8064_mdio *priv = bus->priv;
	u32 ret_val;
	int err;

	miiaddr |= ((phy_addr << MII_ADDR_SHIFT) & MII_ADDR_MASK) |
		   ((reg_offset << MII_REG_SHIFT) & MII_REG_MASK);

	regmap_write(priv->base, MII_ADDR_REG_ADDR, miiaddr);
	usleep_range(10, 13);

	err = ipq8064_mdio_wait_busy(priv);
	if (err)
		return err;

	regmap_read(priv->base, MII_DATA_REG_ADDR, &ret_val);
	return (int)ret_val;
}

static int
ipq8064_mdio_write(struct mii_bus *bus, int phy_addr, int reg_offset, u16 data)
{
	u32 miiaddr = MII_WRITE | MII_BUSY | MII_CLKRANGE_250_300M;
	struct ipq8064_mdio *priv = bus->priv;

	regmap_write(priv->base, MII_DATA_REG_ADDR, data);

	miiaddr |= ((phy_addr << MII_ADDR_SHIFT) & MII_ADDR_MASK) |
		   ((reg_offset << MII_REG_SHIFT) & MII_REG_MASK);

	regmap_write(priv->base, MII_ADDR_REG_ADDR, miiaddr);

	/* For the specific reg 31 extra time is needed or the next
	 * read will produce garbage data.
	 */
	if (reg_offset == 31)
		usleep_range(30, 43);
	else
		usleep_range(10, 13);

	return ipq8064_mdio_wait_busy(priv);
}

static const struct regmap_config ipq8064_mdio_regmap_config = {
	.reg_bits = 32,
	.reg_stride = 4,
	.val_bits = 32,
	.can_multi_write = false,
	/* the mdio lock is used by any user of this mdio driver */
	.disable_locking = true,

	.cache_type = REGCACHE_NONE,
};

static int
ipq8064_mdio_probe(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	struct ipq8064_mdio *priv;
	struct resource res;
	struct mii_bus *bus;
	void __iomem *base;
	int ret;

	if (of_address_to_resource(np, 0, &res))
		return -ENOMEM;

	base = devm_ioremap(&pdev->dev, res.start, resource_size(&res));
	if (!base)
		return -ENOMEM;

	bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));
	if (!bus)

Annotation

Implementation Notes