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path: root/drivers/net/mdio/mdio-sun4i.c
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Diffstat (limited to 'drivers/net/mdio/mdio-sun4i.c')
-rw-r--r--drivers/net/mdio/mdio-sun4i.c180
1 files changed, 180 insertions, 0 deletions
diff --git a/drivers/net/mdio/mdio-sun4i.c b/drivers/net/mdio/mdio-sun4i.c
new file mode 100644
index 000000000000..f798de3276dc
--- /dev/null
+++ b/drivers/net/mdio/mdio-sun4i.c
@@ -0,0 +1,180 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Allwinner EMAC MDIO interface driver
+ *
+ * Copyright 2012-2013 Stefan Roese <sr@denx.de>
+ * Copyright 2013 Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * Based on the Linux driver provided by Allwinner:
+ * Copyright (C) 1997 Sten Wang
+ */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_address.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+
+#define EMAC_MAC_MCMD_REG (0x00)
+#define EMAC_MAC_MADR_REG (0x04)
+#define EMAC_MAC_MWTD_REG (0x08)
+#define EMAC_MAC_MRDD_REG (0x0c)
+#define EMAC_MAC_MIND_REG (0x10)
+#define EMAC_MAC_SSRR_REG (0x14)
+
+#define MDIO_TIMEOUT (msecs_to_jiffies(100))
+
+struct sun4i_mdio_data {
+ void __iomem *membase;
+ struct regulator *regulator;
+};
+
+static int sun4i_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
+{
+ struct sun4i_mdio_data *data = bus->priv;
+ unsigned long timeout_jiffies;
+ int value;
+
+ /* issue the phy address and reg */
+ writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
+ /* pull up the phy io line */
+ writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
+
+ /* Wait read complete */
+ timeout_jiffies = jiffies + MDIO_TIMEOUT;
+ while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
+ if (time_is_before_jiffies(timeout_jiffies))
+ return -ETIMEDOUT;
+ msleep(1);
+ }
+
+ /* push down the phy io line */
+ writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
+ /* and read data */
+ value = readl(data->membase + EMAC_MAC_MRDD_REG);
+
+ return value;
+}
+
+static int sun4i_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
+ u16 value)
+{
+ struct sun4i_mdio_data *data = bus->priv;
+ unsigned long timeout_jiffies;
+
+ /* issue the phy address and reg */
+ writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
+ /* pull up the phy io line */
+ writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
+
+ /* Wait read complete */
+ timeout_jiffies = jiffies + MDIO_TIMEOUT;
+ while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
+ if (time_is_before_jiffies(timeout_jiffies))
+ return -ETIMEDOUT;
+ msleep(1);
+ }
+
+ /* push down the phy io line */
+ writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
+ /* and write data */
+ writel(value, data->membase + EMAC_MAC_MWTD_REG);
+
+ return 0;
+}
+
+static int sun4i_mdio_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct mii_bus *bus;
+ struct sun4i_mdio_data *data;
+ int ret;
+
+ bus = mdiobus_alloc_size(sizeof(*data));
+ if (!bus)
+ return -ENOMEM;
+
+ bus->name = "sun4i_mii_bus";
+ bus->read = &sun4i_mdio_read;
+ bus->write = &sun4i_mdio_write;
+ snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
+ 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->regulator = devm_regulator_get(&pdev->dev, "phy");
+ if (IS_ERR(data->regulator)) {
+ if (PTR_ERR(data->regulator) == -EPROBE_DEFER) {
+ ret = -EPROBE_DEFER;
+ goto err_out_free_mdiobus;
+ }
+
+ dev_info(&pdev->dev, "no regulator found\n");
+ data->regulator = NULL;
+ } else {
+ ret = regulator_enable(data->regulator);
+ if (ret)
+ goto err_out_free_mdiobus;
+ }
+
+ ret = of_mdiobus_register(bus, np);
+ if (ret < 0)
+ goto err_out_disable_regulator;
+
+ platform_set_drvdata(pdev, bus);
+
+ return 0;
+
+err_out_disable_regulator:
+ if (data->regulator)
+ regulator_disable(data->regulator);
+err_out_free_mdiobus:
+ mdiobus_free(bus);
+ return ret;
+}
+
+static int sun4i_mdio_remove(struct platform_device *pdev)
+{
+ struct mii_bus *bus = platform_get_drvdata(pdev);
+ struct sun4i_mdio_data *data = bus->priv;
+
+ mdiobus_unregister(bus);
+ if (data->regulator)
+ regulator_disable(data->regulator);
+ mdiobus_free(bus);
+
+ return 0;
+}
+
+static const struct of_device_id sun4i_mdio_dt_ids[] = {
+ { .compatible = "allwinner,sun4i-a10-mdio" },
+
+ /* Deprecated */
+ { .compatible = "allwinner,sun4i-mdio" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, sun4i_mdio_dt_ids);
+
+static struct platform_driver sun4i_mdio_driver = {
+ .probe = sun4i_mdio_probe,
+ .remove = sun4i_mdio_remove,
+ .driver = {
+ .name = "sun4i-mdio",
+ .of_match_table = sun4i_mdio_dt_ids,
+ },
+};
+
+module_platform_driver(sun4i_mdio_driver);
+
+MODULE_DESCRIPTION("Allwinner EMAC MDIO interface driver");
+MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
+MODULE_LICENSE("GPL v2");