diff options
Diffstat (limited to 'drivers/net/phy/mdio-ipq4019.c')
| -rw-r--r-- | drivers/net/phy/mdio-ipq4019.c | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/drivers/net/phy/mdio-ipq4019.c b/drivers/net/phy/mdio-ipq4019.c new file mode 100644 index 000000000000..1ce81ff2f41d --- /dev/null +++ b/drivers/net/phy/mdio-ipq4019.c @@ -0,0 +1,160 @@ +// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause +/* Copyright (c) 2015, The Linux Foundation. All rights reserved. */ +/* Copyright (c) 2020 Sartura Ltd. */ + +#include <linux/delay.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/iopoll.h> +#include <linux/of_address.h> +#include <linux/of_mdio.h> +#include <linux/phy.h> +#include <linux/platform_device.h> + +#define MDIO_ADDR_REG 0x44 +#define MDIO_DATA_WRITE_REG 0x48 +#define MDIO_DATA_READ_REG 0x4c +#define MDIO_CMD_REG 0x50 +#define MDIO_CMD_ACCESS_BUSY BIT(16) +#define MDIO_CMD_ACCESS_START BIT(8) +#define MDIO_CMD_ACCESS_CODE_READ 0 +#define MDIO_CMD_ACCESS_CODE_WRITE 1 + +#define ipq4019_MDIO_TIMEOUT 10000 +#define ipq4019_MDIO_SLEEP 10 + +struct ipq4019_mdio_data { + void __iomem *membase; +}; + +static int ipq4019_mdio_wait_busy(struct mii_bus *bus) +{ + struct ipq4019_mdio_data *priv = bus->priv; + unsigned int busy; + + return readl_poll_timeout(priv->membase + MDIO_CMD_REG, busy, + (busy & MDIO_CMD_ACCESS_BUSY) == 0, + ipq4019_MDIO_SLEEP, ipq4019_MDIO_TIMEOUT); +} + +static int ipq4019_mdio_read(struct mii_bus *bus, int mii_id, int regnum) +{ + struct ipq4019_mdio_data *priv = bus->priv; + unsigned int cmd; + + /* Reject clause 45 */ + if (regnum & MII_ADDR_C45) + return -EOPNOTSUPP; + + if (ipq4019_mdio_wait_busy(bus)) + return -ETIMEDOUT; + + /* issue the phy address and reg */ + writel((mii_id << 8) | regnum, priv->membase + MDIO_ADDR_REG); + + cmd = MDIO_CMD_ACCESS_START | MDIO_CMD_ACCESS_CODE_READ; + + /* issue read command */ + writel(cmd, priv->membase + MDIO_CMD_REG); + + /* Wait read complete */ + if (ipq4019_mdio_wait_busy(bus)) + return -ETIMEDOUT; + + /* Read and return data */ + return readl(priv->membase + MDIO_DATA_READ_REG); +} + +static int ipq4019_mdio_write(struct mii_bus *bus, int mii_id, int regnum, + u16 value) +{ + struct ipq4019_mdio_data *priv = bus->priv; + unsigned int cmd; + + /* Reject clause 45 */ + if (regnum & MII_ADDR_C45) + return -EOPNOTSUPP; + + if (ipq4019_mdio_wait_busy(bus)) + return -ETIMEDOUT; + + /* issue the phy address and reg */ + writel((mii_id << 8) | regnum, priv->membase + MDIO_ADDR_REG); + + /* issue write data */ + writel(value, priv->membase + MDIO_DATA_WRITE_REG); + + cmd = MDIO_CMD_ACCESS_START | MDIO_CMD_ACCESS_CODE_WRITE; + /* issue write command */ + writel(cmd, priv->membase + MDIO_CMD_REG); + + /* Wait write complete */ + if (ipq4019_mdio_wait_busy(bus)) + return -ETIMEDOUT; + + return 0; +} + +static int ipq4019_mdio_probe(struct platform_device *pdev) +{ + struct ipq4019_mdio_data *priv; + struct mii_bus *bus; + int ret; + + bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv)); + if (!bus) + return -ENOMEM; + + priv = bus->priv; + + priv->membase = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->membase)) + return PTR_ERR(priv->membase); + + bus->name = "ipq4019_mdio"; + bus->read = ipq4019_mdio_read; + bus->write = ipq4019_mdio_write; + bus->parent = &pdev->dev; + snprintf(bus->id, MII_BUS_ID_SIZE, "%s%d", pdev->name, pdev->id); + + ret = of_mdiobus_register(bus, pdev->dev.of_node); + if (ret) { + dev_err(&pdev->dev, "Cannot register MDIO bus!\n"); + return ret; + } + + platform_set_drvdata(pdev, bus); + + return 0; +} + +static int ipq4019_mdio_remove(struct platform_device *pdev) +{ + struct mii_bus *bus = platform_get_drvdata(pdev); + + mdiobus_unregister(bus); + + return 0; +} + +static const struct of_device_id ipq4019_mdio_dt_ids[] = { + { .compatible = "qcom,ipq4019-mdio" }, + { } +}; +MODULE_DEVICE_TABLE(of, ipq4019_mdio_dt_ids); + +static struct platform_driver ipq4019_mdio_driver = { + .probe = ipq4019_mdio_probe, + .remove = ipq4019_mdio_remove, + .driver = { + .name = "ipq4019-mdio", + .of_match_table = ipq4019_mdio_dt_ids, + }, +}; + +module_platform_driver(ipq4019_mdio_driver); + +MODULE_DESCRIPTION("ipq4019 MDIO interface driver"); +MODULE_AUTHOR("Qualcomm Atheros"); +MODULE_LICENSE("Dual BSD/GPL"); |