/* * 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 * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. */ #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; struct resource *res; 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; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); data->membase = devm_ioremap_resource(&pdev->dev, res); 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) return -EPROBE_DEFER; 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); mdiobus_unregister(bus); 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");