net: phy: mdio: add IPQ4019 MDIO driver

This patch adds the driver for the MDIO interface
inside of Qualcomm IPQ40xx series SoC-s.

Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Cc: Luka Perkov <luka.perkov@sartura.hr>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig
index bacfee4..2a32f26 100644 (file)
--- a/drivers/net/phy/Kconfig
+++ b/drivers/net/phy/Kconfig
@@ -157,6 +157,13 @@ config MDIO_I2C
 
          This is library mode.
 
+config MDIO_IPQ4019
+       tristate "Qualcomm IPQ4019 MDIO interface support"
+       depends on HAS_IOMEM && OF_MDIO
+       help
+         This driver supports the MDIO interface found in Qualcomm
+         IPQ40xx series Soc-s.
+
 config MDIO_IPQ8064
        tristate "Qualcomm IPQ8064 MDIO interface support"
        depends on HAS_IOMEM && OF_MDIO

diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile
index cd345b7..dc9e53b 100644 (file)
--- a/drivers/net/phy/Makefile
+++ b/drivers/net/phy/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_MDIO_CAVIUM)     += mdio-cavium.o
 obj-$(CONFIG_MDIO_GPIO)                += mdio-gpio.o
 obj-$(CONFIG_MDIO_HISI_FEMAC)  += mdio-hisi-femac.o
 obj-$(CONFIG_MDIO_I2C)         += mdio-i2c.o
+obj-$(CONFIG_MDIO_IPQ4019)     += mdio-ipq4019.o
 obj-$(CONFIG_MDIO_IPQ8064)     += mdio-ipq8064.o
 obj-$(CONFIG_MDIO_MOXART)      += mdio-moxart.o
 obj-$(CONFIG_MDIO_MSCC_MIIM)   += mdio-mscc-miim.o

diff --git a/drivers/net/phy/mdio-ipq4019.c b/drivers/net/phy/mdio-ipq4019.c
new file mode 100644 (file)
index 0000000..1ce81ff
--- /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");