net: mdio: Move MDIO drivers into a new subdirectory

Move all the MDIO drivers and multiplexers into drivers/net/mdio.  The
mdio core is however left in the phy directory, due to mutual
dependencies between the MDIO core and the PHY core.

Take this opportunity to sort the Kconfig based on the menuconfig
strings, and move the multiplexers to the end with a separating
comment.

v2:
Fix typo in commit message

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 157 insertions, 0 deletions

diff --git a/drivers/net/mdio/mdio-aspeed.c b/drivers/net/mdio/mdio-aspeed.c
new file mode 100644
index 000000000000..cad820568f75
--- /dev/null
+++ b/drivers/net/mdio/mdio-aspeed.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Copyright (C) 2019 IBM Corp. */
+
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+#include <linux/mdio.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+
+#define DRV_NAME "mdio-aspeed"
+
+#define ASPEED_MDIO_CTRL		0x0
+#define   ASPEED_MDIO_CTRL_FIRE		BIT(31)
+#define   ASPEED_MDIO_CTRL_ST		BIT(28)
+#define     ASPEED_MDIO_CTRL_ST_C45	0
+#define     ASPEED_MDIO_CTRL_ST_C22	1
+#define   ASPEED_MDIO_CTRL_OP		GENMASK(27, 26)
+#define     MDIO_C22_OP_WRITE		0b01
+#define     MDIO_C22_OP_READ		0b10
+#define   ASPEED_MDIO_CTRL_PHYAD	GENMASK(25, 21)
+#define   ASPEED_MDIO_CTRL_REGAD	GENMASK(20, 16)
+#define   ASPEED_MDIO_CTRL_MIIWDATA	GENMASK(15, 0)
+
+#define ASPEED_MDIO_DATA		0x4
+#define   ASPEED_MDIO_DATA_MDC_THRES	GENMASK(31, 24)
+#define   ASPEED_MDIO_DATA_MDIO_EDGE	BIT(23)
+#define   ASPEED_MDIO_DATA_MDIO_LATCH	GENMASK(22, 20)
+#define   ASPEED_MDIO_DATA_IDLE		BIT(16)
+#define   ASPEED_MDIO_DATA_MIIRDATA	GENMASK(15, 0)
+
+#define ASPEED_MDIO_INTERVAL_US		100
+#define ASPEED_MDIO_TIMEOUT_US		(ASPEED_MDIO_INTERVAL_US * 10)
+
+struct aspeed_mdio {
+	void __iomem *base;
+};
+
+static int aspeed_mdio_read(struct mii_bus *bus, int addr, int regnum)
+{
+	struct aspeed_mdio *ctx = bus->priv;
+	u32 ctrl;
+	u32 data;
+	int rc;
+
+	dev_dbg(&bus->dev, "%s: addr: %d, regnum: %d\n", __func__, addr,
+		regnum);
+
+	/* Just clause 22 for the moment */
+	if (regnum & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	ctrl = ASPEED_MDIO_CTRL_FIRE
+		| FIELD_PREP(ASPEED_MDIO_CTRL_ST, ASPEED_MDIO_CTRL_ST_C22)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_OP, MDIO_C22_OP_READ)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_PHYAD, addr)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_REGAD, regnum);
+
+	iowrite32(ctrl, ctx->base + ASPEED_MDIO_CTRL);
+
+	rc = readl_poll_timeout(ctx->base + ASPEED_MDIO_DATA, data,
+				data & ASPEED_MDIO_DATA_IDLE,
+				ASPEED_MDIO_INTERVAL_US,
+				ASPEED_MDIO_TIMEOUT_US);
+	if (rc < 0)
+		return rc;
+
+	return FIELD_GET(ASPEED_MDIO_DATA_MIIRDATA, data);
+}
+
+static int aspeed_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val)
+{
+	struct aspeed_mdio *ctx = bus->priv;
+	u32 ctrl;
+
+	dev_dbg(&bus->dev, "%s: addr: %d, regnum: %d, val: 0x%x\n",
+		__func__, addr, regnum, val);
+
+	/* Just clause 22 for the moment */
+	if (regnum & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	ctrl = ASPEED_MDIO_CTRL_FIRE
+		| FIELD_PREP(ASPEED_MDIO_CTRL_ST, ASPEED_MDIO_CTRL_ST_C22)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_OP, MDIO_C22_OP_WRITE)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_PHYAD, addr)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_REGAD, regnum)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_MIIWDATA, val);
+
+	iowrite32(ctrl, ctx->base + ASPEED_MDIO_CTRL);
+
+	return readl_poll_timeout(ctx->base + ASPEED_MDIO_CTRL, ctrl,
+				  !(ctrl & ASPEED_MDIO_CTRL_FIRE),
+				  ASPEED_MDIO_INTERVAL_US,
+				  ASPEED_MDIO_TIMEOUT_US);
+}
+
+static int aspeed_mdio_probe(struct platform_device *pdev)
+{
+	struct aspeed_mdio *ctx;
+	struct mii_bus *bus;
+	int rc;
+
+	bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*ctx));
+	if (!bus)
+		return -ENOMEM;
+
+	ctx = bus->priv;
+	ctx->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(ctx->base))
+		return PTR_ERR(ctx->base);
+
+	bus->name = DRV_NAME;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s%d", pdev->name, pdev->id);
+	bus->parent = &pdev->dev;
+	bus->read = aspeed_mdio_read;
+	bus->write = aspeed_mdio_write;
+
+	rc = of_mdiobus_register(bus, pdev->dev.of_node);
+	if (rc) {
+		dev_err(&pdev->dev, "Cannot register MDIO bus!\n");
+		return rc;
+	}
+
+	platform_set_drvdata(pdev, bus);
+
+	return 0;
+}
+
+static int aspeed_mdio_remove(struct platform_device *pdev)
+{
+	mdiobus_unregister(platform_get_drvdata(pdev));
+
+	return 0;
+}
+
+static const struct of_device_id aspeed_mdio_of_match[] = {
+	{ .compatible = "aspeed,ast2600-mdio", },
+	{ },
+};
+
+static struct platform_driver aspeed_mdio_driver = {
+	.driver = {
+		.name = DRV_NAME,
+		.of_match_table = aspeed_mdio_of_match,
+	},
+	.probe = aspeed_mdio_probe,
+	.remove = aspeed_mdio_remove,
+};
+
+module_platform_driver(aspeed_mdio_driver);
+
+MODULE_AUTHOR("Andrew Jeffery <andrew@aj.id.au>");
+MODULE_LICENSE("GPL");