1 files changed, 152 insertions, 0 deletions
diff --git a/drivers/net/mdio/mdio-hisi-femac.c b/drivers/net/mdio/mdio-hisi-femac.c
new file mode 100644
index 0000000000..f231c2fbb1
--- /dev/null
+++ b/drivers/net/mdio/mdio-hisi-femac.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Hisilicon Fast Ethernet MDIO Bus Driver
+ *
+ * Copyright (c) 2016 HiSilicon Technologies Co., Ltd.
+ */
+
+#include <linux/clk.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_mdio.h>
+#include <linux/platform_device.h>
+
+#define MDIO_RWCTRL		0x00
+#define MDIO_RO_DATA		0x04
+#define MDIO_WRITE		BIT(13)
+#define MDIO_RW_FINISH		BIT(15)
+#define BIT_PHY_ADDR_OFFSET	8
+#define BIT_WR_DATA_OFFSET	16
+
+struct hisi_femac_mdio_data {
+	struct clk *clk;
+	void __iomem *membase;
+};
+
+static int hisi_femac_mdio_wait_ready(struct hisi_femac_mdio_data *data)
+{
+	u32 val;
+
+	return readl_poll_timeout(data->membase + MDIO_RWCTRL,
+				  val, val & MDIO_RW_FINISH, 20, 10000);
+}
+
+static int hisi_femac_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
+{
+	struct hisi_femac_mdio_data *data = bus->priv;
+	int ret;
+
+	ret = hisi_femac_mdio_wait_ready(data);
+	if (ret)
+		return ret;
+
+	writel((mii_id << BIT_PHY_ADDR_OFFSET) | regnum,
+	       data->membase + MDIO_RWCTRL);
+
+	ret = hisi_femac_mdio_wait_ready(data);
+	if (ret)
+		return ret;
+
+	return readl(data->membase + MDIO_RO_DATA) & 0xFFFF;
+}
+
+static int hisi_femac_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
+				 u16 value)
+{
+	struct hisi_femac_mdio_data *data = bus->priv;
+	int ret;
+
+	ret = hisi_femac_mdio_wait_ready(data);
+	if (ret)
+		return ret;
+
+	writel(MDIO_WRITE | (value << BIT_WR_DATA_OFFSET) |
+	       (mii_id << BIT_PHY_ADDR_OFFSET) | regnum,
+	       data->membase + MDIO_RWCTRL);
+
+	return hisi_femac_mdio_wait_ready(data);
+}
+
+static int hisi_femac_mdio_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct mii_bus *bus;
+	struct hisi_femac_mdio_data *data;
+	int ret;
+
+	bus = mdiobus_alloc_size(sizeof(*data));
+	if (!bus)
+		return -ENOMEM;
+
+	bus->name = "hisi_femac_mii_bus";
+	bus->read = &hisi_femac_mdio_read;
+	bus->write = &hisi_femac_mdio_write;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s", pdev->name);
+	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->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(data->clk)) {
+		ret = PTR_ERR(data->clk);
+		goto err_out_free_mdiobus;
+	}
+
+	ret = clk_prepare_enable(data->clk);
+	if (ret)
+		goto err_out_free_mdiobus;
+
+	ret = of_mdiobus_register(bus, np);
+	if (ret)
+		goto err_out_disable_clk;
+
+	platform_set_drvdata(pdev, bus);
+
+	return 0;
+
+err_out_disable_clk:
+	clk_disable_unprepare(data->clk);
+err_out_free_mdiobus:
+	mdiobus_free(bus);
+	return ret;
+}
+
+static int hisi_femac_mdio_remove(struct platform_device *pdev)
+{
+	struct mii_bus *bus = platform_get_drvdata(pdev);
+	struct hisi_femac_mdio_data *data = bus->priv;
+
+	mdiobus_unregister(bus);
+	clk_disable_unprepare(data->clk);
+	mdiobus_free(bus);
+
+	return 0;
+}
+
+static const struct of_device_id hisi_femac_mdio_dt_ids[] = {
+	{ .compatible = "hisilicon,hisi-femac-mdio" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, hisi_femac_mdio_dt_ids);
+
+static struct platform_driver hisi_femac_mdio_driver = {
+	.probe = hisi_femac_mdio_probe,
+	.remove = hisi_femac_mdio_remove,
+	.driver = {
+		.name = "hisi-femac-mdio",
+		.of_match_table = hisi_femac_mdio_dt_ids,
+	},
+};
+
+module_platform_driver(hisi_femac_mdio_driver);
+
+MODULE_DESCRIPTION("Hisilicon Fast Ethernet MAC MDIO interface driver");
+MODULE_AUTHOR("Dongpo Li <lidongpo@hisilicon.com>");
+MODULE_LICENSE("GPL");