diff options
Diffstat (limited to 'drivers/net/phy/mdio-sun4i.c')
| -rw-r--r-- | drivers/net/phy/mdio-sun4i.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/drivers/net/phy/mdio-sun4i.c b/drivers/net/phy/mdio-sun4i.c new file mode 100644 index 00000000000..61d3f4ebf52 --- /dev/null +++ b/drivers/net/phy/mdio-sun4i.c @@ -0,0 +1,194 @@ +/* + * 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/init.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 start_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 */ + start_jiffies = jiffies; + while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) { + if (time_after(start_jiffies, + start_jiffies + MDIO_TIMEOUT)) + 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 start_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 */ + start_jiffies = jiffies; + while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) { + if (time_after(start_jiffies, + start_jiffies + MDIO_TIMEOUT)) + 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_reset(struct mii_bus *bus) +{ + 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, i; + + 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; + bus->reset = &sun4i_mdio_reset; + snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev)); + bus->parent = &pdev->dev; + + bus->irq = kmalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL); + if (!bus->irq) { + ret = -ENOMEM; + goto err_out_free_mdiobus; + } + + for (i = 0; i < PHY_MAX_ADDR; i++) + bus->irq[i] = PHY_POLL; + + data = bus->priv; + data->membase = of_iomap(np, 0); + if (!data->membase) { + ret = -ENOMEM; + goto err_out_free_mdio_irq; + } + + 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"); + } else { + ret = regulator_enable(data->regulator); + if (ret) + goto err_out_free_mdio_irq; + } + + 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: + regulator_disable(data->regulator); +err_out_free_mdio_irq: + kfree(bus->irq); +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); + kfree(bus->irq); + mdiobus_free(bus); + + return 0; +} + +static const struct of_device_id sun4i_mdio_dt_ids[] = { + { .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"); |