/* MOXA ART Ethernet (RTL8201CP) MDIO interface driver * * Copyright (C) 2013 Jonas Jensen <jonas.jensen@gmail.com> * * 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 REG_PHY_CTRL 0 #define REG_PHY_WRITE_DATA 4 /* REG_PHY_CTRL */ #define MIIWR BIT(27) /* init write sequence (auto cleared)*/ #define MIIRD BIT(26) #define REGAD_MASK 0x3e00000 #define PHYAD_MASK 0x1f0000 #define MIIRDATA_MASK 0xffff /* REG_PHY_WRITE_DATA */ #define MIIWDATA_MASK 0xffff struct moxart_mdio_data { void __iomem *base; }; static int moxart_mdio_read(struct mii_bus *bus, int mii_id, int regnum) { struct moxart_mdio_data *data = bus->priv; u32 ctrl = 0; unsigned int count = 5; dev_dbg(&bus->dev, "%s\n", __func__); ctrl |= MIIRD | ((mii_id << 16) & PHYAD_MASK) | ((regnum << 21) & REGAD_MASK); writel(ctrl, data->base + REG_PHY_CTRL); do { ctrl = readl(data->base + REG_PHY_CTRL); if (!(ctrl & MIIRD)) return ctrl & MIIRDATA_MASK; mdelay(10); count--; } while (count > 0); dev_dbg(&bus->dev, "%s timed out\n", __func__); return -ETIMEDOUT; } static int moxart_mdio_write(struct mii_bus *bus, int mii_id, int regnum, u16 value) { struct moxart_mdio_data *data = bus->priv; u32 ctrl = 0; unsigned int count = 5; dev_dbg(&bus->dev, "%s\n", __func__); ctrl |= MIIWR | ((mii_id << 16) & PHYAD_MASK) | ((regnum << 21) & REGAD_MASK); value &= MIIWDATA_MASK; writel(value, data->base + REG_PHY_WRITE_DATA); writel(ctrl, data->base + REG_PHY_CTRL); do { ctrl = readl(data->base + REG_PHY_CTRL); if (!(ctrl & MIIWR)) return 0; mdelay(10); count--; } while (count > 0); dev_dbg(&bus->dev, "%s timed out\n", __func__); return -ETIMEDOUT; } static int moxart_mdio_reset(struct mii_bus *bus) { int data, i; for (i = 0; i < PHY_MAX_ADDR; i++) { data = moxart_mdio_read(bus, i, MII_BMCR); if (data < 0) continue; data |= BMCR_RESET; if (moxart_mdio_write(bus, i, MII_BMCR, data) < 0) continue; } return 0; } static int moxart_mdio_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; struct mii_bus *bus; struct moxart_mdio_data *data; struct resource *res; int ret, i; bus = mdiobus_alloc_size(sizeof(*data)); if (!bus) return -ENOMEM; bus->name = "MOXA ART Ethernet MII"; bus->read = &moxart_mdio_read; bus->write = &moxart_mdio_write; bus->reset = &moxart_mdio_reset; snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d-mii", pdev->name, pdev->id); bus->parent = &pdev->dev; /* Setting PHY_IGNORE_INTERRUPT here even if it has no effect, * of_mdiobus_register() sets these PHY_POLL. * Ideally, the interrupt from MAC controller could be used to * detect link state changes, not polling, i.e. if there was * a way phy_driver could set PHY_HAS_INTERRUPT but have that * interrupt handled in ethernet drivercode. */ for (i = 0; i < PHY_MAX_ADDR; i++) bus->irq[i] = PHY_IGNORE_INTERRUPT; data = bus->priv; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); data->base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(data->base)) { ret = PTR_ERR(data->base); goto err_out_free_mdiobus; } ret = of_mdiobus_register(bus, np); if (ret < 0) goto err_out_free_mdiobus; platform_set_drvdata(pdev, bus); return 0; err_out_free_mdiobus: mdiobus_free(bus); return ret; } static int moxart_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 moxart_mdio_dt_ids[] = { { .compatible = "moxa,moxart-mdio" }, { } }; MODULE_DEVICE_TABLE(of, moxart_mdio_dt_ids); static struct platform_driver moxart_mdio_driver = { .probe = moxart_mdio_probe, .remove = moxart_mdio_remove, .driver = { .name = "moxart-mdio", .of_match_table = moxart_mdio_dt_ids, }, }; module_platform_driver(moxart_mdio_driver); MODULE_DESCRIPTION("MOXA ART MDIO interface driver"); MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>"); MODULE_LICENSE("GPL");