diff options
Diffstat (limited to 'drivers/net/mdio/mdio-moxart.c')
| -rw-r--r-- | drivers/net/mdio/mdio-moxart.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/drivers/net/mdio/mdio-moxart.c b/drivers/net/mdio/mdio-moxart.c new file mode 100644 index 000000000..b72c6d185 --- /dev/null +++ b/drivers/net/mdio/mdio-moxart.c @@ -0,0 +1,187 @@ +// SPDX-License-Identifier: GPL-2.0 +/* MOXA ART Ethernet (RTL8201CP) MDIO interface driver + * + * Copyright (C) 2013 Jonas Jensen <jonas.jensen@gmail.com> + */ + +#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> + +#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; + 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; + data->base = devm_platform_ioremap_resource(pdev, 0); + 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 v2"); |