--- /dev/null
+/*
+ * Copyright 2016 Broadcom
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation (the "GPL").
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License version 2 (GPLv2) for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * version 2 (GPLv2) along with this source code.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/of_mdio.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+#include <linux/mdio-mux.h>
+#include <linux/delay.h>
+
+#define MDIO_PARAM_OFFSET 0x00
+#define MDIO_PARAM_MIIM_CYCLE 29
+#define MDIO_PARAM_INTERNAL_SEL 25
+#define MDIO_PARAM_BUS_ID 22
+#define MDIO_PARAM_C45_SEL 21
+#define MDIO_PARAM_PHY_ID 16
+#define MDIO_PARAM_PHY_DATA 0
+
+#define MDIO_READ_OFFSET 0x04
+#define MDIO_READ_DATA_MASK 0xffff
+#define MDIO_ADDR_OFFSET 0x08
+
+#define MDIO_CTRL_OFFSET 0x0C
+#define MDIO_CTRL_WRITE_OP 0x1
+#define MDIO_CTRL_READ_OP 0x2
+
+#define MDIO_STAT_OFFSET 0x10
+#define MDIO_STAT_DONE 1
+
+#define BUS_MAX_ADDR 32
+#define EXT_BUS_START_ADDR 16
+
+struct iproc_mdiomux_desc {
+ void *mux_handle;
+ void __iomem *base;
+ struct device *dev;
+ struct mii_bus *mii_bus;
+};
+
+static int iproc_mdio_wait_for_idle(void __iomem *base, bool result)
+{
+ unsigned int timeout = 1000; /* loop for 1s */
+ u32 val;
+
+ do {
+ val = readl(base + MDIO_STAT_OFFSET);
+ if ((val & MDIO_STAT_DONE) == result)
+ return 0;
+
+ usleep_range(1000, 2000);
+ } while (timeout--);
+
+ return -ETIMEDOUT;
+}
+
+/* start_miim_ops- Program and start MDIO transaction over mdio bus.
+ * @base: Base address
+ * @phyid: phyid of the selected bus.
+ * @reg: register offset to be read/written.
+ * @val :0 if read op else value to be written in @reg;
+ * @op: Operation that need to be carried out.
+ * MDIO_CTRL_READ_OP: Read transaction.
+ * MDIO_CTRL_WRITE_OP: Write transaction.
+ *
+ * Return value: Successful Read operation returns read reg values and write
+ * operation returns 0. Failure operation returns negative error code.
+ */
+static int start_miim_ops(void __iomem *base,
+ u16 phyid, u32 reg, u16 val, u32 op)
+{
+ u32 param;
+ int ret;
+
+ writel(0, base + MDIO_CTRL_OFFSET);
+ ret = iproc_mdio_wait_for_idle(base, 0);
+ if (ret)
+ goto err;
+
+ param = readl(base + MDIO_PARAM_OFFSET);
+ param |= phyid << MDIO_PARAM_PHY_ID;
+ param |= val << MDIO_PARAM_PHY_DATA;
+ if (reg & MII_ADDR_C45)
+ param |= BIT(MDIO_PARAM_C45_SEL);
+
+ writel(param, base + MDIO_PARAM_OFFSET);
+
+ writel(reg, base + MDIO_ADDR_OFFSET);
+
+ writel(op, base + MDIO_CTRL_OFFSET);
+
+ ret = iproc_mdio_wait_for_idle(base, 1);
+ if (ret)
+ goto err;
+
+ if (op == MDIO_CTRL_READ_OP)
+ ret = readl(base + MDIO_READ_OFFSET) & MDIO_READ_DATA_MASK;
+err:
+ return ret;
+}
+
+static int iproc_mdiomux_read(struct mii_bus *bus, int phyid, int reg)
+{
+ struct iproc_mdiomux_desc *md = bus->priv;
+ int ret;
+
+ ret = start_miim_ops(md->base, phyid, reg, 0, MDIO_CTRL_READ_OP);
+ if (ret < 0)
+ dev_err(&bus->dev, "mdiomux read operation failed!!!");
+
+ return ret;
+}
+
+static int iproc_mdiomux_write(struct mii_bus *bus,
+ int phyid, int reg, u16 val)
+{
+ struct iproc_mdiomux_desc *md = bus->priv;
+ int ret;
+
+ /* Write val at reg offset */
+ ret = start_miim_ops(md->base, phyid, reg, val, MDIO_CTRL_WRITE_OP);
+ if (ret < 0)
+ dev_err(&bus->dev, "mdiomux write operation failed!!!");
+
+ return ret;
+}
+
+static int mdio_mux_iproc_switch_fn(int current_child, int desired_child,
+ void *data)
+{
+ struct iproc_mdiomux_desc *md = data;
+ u32 param, bus_id;
+ bool bus_dir;
+
+ /* select bus and its properties */
+ bus_dir = (desired_child < EXT_BUS_START_ADDR);
+ bus_id = bus_dir ? desired_child : (desired_child - EXT_BUS_START_ADDR);
+
+ param = (bus_dir ? 1 : 0) << MDIO_PARAM_INTERNAL_SEL;
+ param |= (bus_id << MDIO_PARAM_BUS_ID);
+
+ writel(param, md->base + MDIO_PARAM_OFFSET);
+ return 0;
+}
+
+static int mdio_mux_iproc_probe(struct platform_device *pdev)
+{
+ struct iproc_mdiomux_desc *md;
+ struct mii_bus *bus;
+ struct resource *res;
+ int rc;
+
+ md = devm_kzalloc(&pdev->dev, sizeof(*md), GFP_KERNEL);
+ if (!md)
+ return -ENOMEM;
+ md->dev = &pdev->dev;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ md->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(md->base)) {
+ dev_err(&pdev->dev, "failed to ioremap register\n");
+ return PTR_ERR(md->base);
+ }
+
+ md->mii_bus = mdiobus_alloc();
+ if (!md->mii_bus) {
+ dev_err(&pdev->dev, "mdiomux bus alloc failed\n");
+ return -ENOMEM;
+ }
+
+ bus = md->mii_bus;
+ bus->priv = md;
+ bus->name = "iProc MDIO mux bus";
+ snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d", pdev->name, pdev->id);
+ bus->parent = &pdev->dev;
+ bus->read = iproc_mdiomux_read;
+ bus->write = iproc_mdiomux_write;
+
+ bus->phy_mask = ~0;
+ bus->dev.of_node = pdev->dev.of_node;
+ rc = mdiobus_register(bus);
+ if (rc) {
+ dev_err(&pdev->dev, "mdiomux registration failed\n");
+ goto out;
+ }
+
+ platform_set_drvdata(pdev, md);
+
+ rc = mdio_mux_init(md->dev, mdio_mux_iproc_switch_fn,
+ &md->mux_handle, md, md->mii_bus);
+ if (rc) {
+ dev_info(md->dev, "mdiomux initialization failed\n");
+ goto out;
+ }
+
+ dev_info(md->dev, "iProc mdiomux registered\n");
+ return 0;
+out:
+ mdiobus_free(bus);
+ return rc;
+}
+
+static int mdio_mux_iproc_remove(struct platform_device *pdev)
+{
+ struct iproc_mdiomux_desc *md = dev_get_platdata(&pdev->dev);
+
+ mdio_mux_uninit(md->mux_handle);
+ mdiobus_unregister(md->mii_bus);
+ mdiobus_free(md->mii_bus);
+
+ return 0;
+}
+
+static const struct of_device_id mdio_mux_iproc_match[] = {
+ {
+ .compatible = "brcm,mdio-mux-iproc",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, mdio_mux_iproc_match);
+
+static struct platform_driver mdiomux_iproc_driver = {
+ .driver = {
+ .name = "mdio-mux-iproc",
+ .of_match_table = mdio_mux_iproc_match,
+ },
+ .probe = mdio_mux_iproc_probe,
+ .remove = mdio_mux_iproc_remove,
+};
+
+module_platform_driver(mdiomux_iproc_driver);
+
+MODULE_DESCRIPTION("iProc MDIO Mux Bus Driver");
+MODULE_AUTHOR("Pramod Kumar <pramod.kumar@broadcom.com>");
+MODULE_LICENSE("GPL v2");
projects / GitHub / MotorolaMobilityLLC / kernel-slsi.git / commitdiff