--- /dev/null
+/*
+ * GPIO based MDIO bitbang driver.
+ * Supports OpenFirmware.
+ *
+ * Copyright (c) 2008 CSE Semaphore Belgium.
+ * by Laurent Pinchart <laurentp@cse-semaphore.com>
+ *
+ * Copyright (C) 2008, Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
+ *
+ * Based on earlier work by
+ *
+ * Copyright (c) 2003 Intracom S.A.
+ * by Pantelis Antoniou <panto@intracom.gr>
+ *
+ * 2005 (c) MontaVista Software, Inc.
+ * Vitaly Bordug <vbordug@ru.mvista.com>
+ *
+ * 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/module.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/mdio-gpio.h>
+
+#include <linux/of_gpio.h>
+#include <linux/of_mdio.h>
+
+struct mdio_gpio_info {
+ struct mdiobb_ctrl ctrl;
+ int mdc, mdio, mdo;
+ int mdc_active_low, mdio_active_low, mdo_active_low;
+};
+
+static void *mdio_gpio_of_get_data(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct mdio_gpio_platform_data *pdata;
+ enum of_gpio_flags flags;
+ int ret;
+
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return NULL;
+
+ ret = of_get_gpio_flags(np, 0, &flags);
+ if (ret < 0)
+ return NULL;
+
+ pdata->mdc = ret;
+ pdata->mdc_active_low = flags & OF_GPIO_ACTIVE_LOW;
+
+ ret = of_get_gpio_flags(np, 1, &flags);
+ if (ret < 0)
+ return NULL;
+ pdata->mdio = ret;
+ pdata->mdio_active_low = flags & OF_GPIO_ACTIVE_LOW;
+
+ ret = of_get_gpio_flags(np, 2, &flags);
+ if (ret > 0) {
+ pdata->mdo = ret;
+ pdata->mdo_active_low = flags & OF_GPIO_ACTIVE_LOW;
+ }
+
+ return pdata;
+}
+
+static void mdio_dir(struct mdiobb_ctrl *ctrl, int dir)
+{
+ struct mdio_gpio_info *bitbang =
+ container_of(ctrl, struct mdio_gpio_info, ctrl);
+
+ if (bitbang->mdo) {
+ /* Separate output pin. Always set its value to high
+ * when changing direction. If direction is input,
+ * assume the pin serves as pull-up. If direction is
+ * output, the default value is high.
+ */
+ gpio_set_value_cansleep(bitbang->mdo,
+ 1 ^ bitbang->mdo_active_low);
+ return;
+ }
+
+ if (dir)
+ gpio_direction_output(bitbang->mdio,
+ 1 ^ bitbang->mdio_active_low);
+ else
+ gpio_direction_input(bitbang->mdio);
+}
+
+static int mdio_get(struct mdiobb_ctrl *ctrl)
+{
+ struct mdio_gpio_info *bitbang =
+ container_of(ctrl, struct mdio_gpio_info, ctrl);
+
+ return gpio_get_value_cansleep(bitbang->mdio) ^
+ bitbang->mdio_active_low;
+}
+
+static void mdio_set(struct mdiobb_ctrl *ctrl, int what)
+{
+ struct mdio_gpio_info *bitbang =
+ container_of(ctrl, struct mdio_gpio_info, ctrl);
+
+ if (bitbang->mdo)
+ gpio_set_value_cansleep(bitbang->mdo,
+ what ^ bitbang->mdo_active_low);
+ else
+ gpio_set_value_cansleep(bitbang->mdio,
+ what ^ bitbang->mdio_active_low);
+}
+
+static void mdc_set(struct mdiobb_ctrl *ctrl, int what)
+{
+ struct mdio_gpio_info *bitbang =
+ container_of(ctrl, struct mdio_gpio_info, ctrl);
+
+ gpio_set_value_cansleep(bitbang->mdc, what ^ bitbang->mdc_active_low);
+}
+
+static struct mdiobb_ops mdio_gpio_ops = {
+ .owner = THIS_MODULE,
+ .set_mdc = mdc_set,
+ .set_mdio_dir = mdio_dir,
+ .set_mdio_data = mdio_set,
+ .get_mdio_data = mdio_get,
+};
+
+static struct mii_bus *mdio_gpio_bus_init(struct device *dev,
+ struct mdio_gpio_platform_data *pdata,
+ int bus_id)
+{
+ struct mii_bus *new_bus;
+ struct mdio_gpio_info *bitbang;
+ int i;
+
+ bitbang = devm_kzalloc(dev, sizeof(*bitbang), GFP_KERNEL);
+ if (!bitbang)
+ goto out;
+
+ bitbang->ctrl.ops = &mdio_gpio_ops;
+ bitbang->ctrl.reset = pdata->reset;
+ bitbang->mdc = pdata->mdc;
+ bitbang->mdc_active_low = pdata->mdc_active_low;
+ bitbang->mdio = pdata->mdio;
+ bitbang->mdio_active_low = pdata->mdio_active_low;
+ bitbang->mdo = pdata->mdo;
+ bitbang->mdo_active_low = pdata->mdo_active_low;
+
+ new_bus = alloc_mdio_bitbang(&bitbang->ctrl);
+ if (!new_bus)
+ goto out;
+
+ new_bus->name = "GPIO Bitbanged MDIO",
+
+ new_bus->phy_mask = pdata->phy_mask;
+ new_bus->irq = pdata->irqs;
+ new_bus->parent = dev;
+
+ if (new_bus->phy_mask == ~0)
+ goto out_free_bus;
+
+ for (i = 0; i < PHY_MAX_ADDR; i++)
+ if (!new_bus->irq[i])
+ new_bus->irq[i] = PHY_POLL;
+
+ if (bus_id != -1)
+ snprintf(new_bus->id, MII_BUS_ID_SIZE, "gpio-%x", bus_id);
+ else
+ strncpy(new_bus->id, "gpio", MII_BUS_ID_SIZE);
+
+ if (devm_gpio_request(dev, bitbang->mdc, "mdc"))
+ goto out_free_bus;
+
+ if (devm_gpio_request(dev, bitbang->mdio, "mdio"))
+ goto out_free_bus;
+
+ if (bitbang->mdo) {
+ if (devm_gpio_request(dev, bitbang->mdo, "mdo"))
+ goto out_free_bus;
+ gpio_direction_output(bitbang->mdo, 1);
+ gpio_direction_input(bitbang->mdio);
+ }
+
+ gpio_direction_output(bitbang->mdc, 0);
+
+ dev_set_drvdata(dev, new_bus);
+
+ return new_bus;
+
+out_free_bus:
+ free_mdio_bitbang(new_bus);
+out:
+ return NULL;
+}
+
+static void mdio_gpio_bus_deinit(struct device *dev)
+{
+ struct mii_bus *bus = dev_get_drvdata(dev);
+
+ free_mdio_bitbang(bus);
+}
+
+static void mdio_gpio_bus_destroy(struct device *dev)
+{
+ struct mii_bus *bus = dev_get_drvdata(dev);
+
+ mdiobus_unregister(bus);
+ mdio_gpio_bus_deinit(dev);
+}
+
+static int mdio_gpio_probe(struct platform_device *pdev)
+{
+ struct mdio_gpio_platform_data *pdata;
+ struct mii_bus *new_bus;
+ int ret, bus_id;
+
+ if (pdev->dev.of_node) {
+ pdata = mdio_gpio_of_get_data(pdev);
+ bus_id = of_alias_get_id(pdev->dev.of_node, "mdio-gpio");
+ if (bus_id < 0) {
+ dev_warn(&pdev->dev, "failed to get alias id\n");
+ bus_id = 0;
+ }
+ } else {
+ pdata = dev_get_platdata(&pdev->dev);
+ bus_id = pdev->id;
+ }
+
+ if (!pdata)
+ return -ENODEV;
+
+ new_bus = mdio_gpio_bus_init(&pdev->dev, pdata, bus_id);
+ if (!new_bus)
+ return -ENODEV;
+
+ if (pdev->dev.of_node)
+ ret = of_mdiobus_register(new_bus, pdev->dev.of_node);
+ else
+ ret = mdiobus_register(new_bus);
+
+ if (ret)
+ mdio_gpio_bus_deinit(&pdev->dev);
+
+ return ret;
+}
+
+static int mdio_gpio_remove(struct platform_device *pdev)
+{
+ mdio_gpio_bus_destroy(&pdev->dev);
+
+ return 0;
+}
+
+static const struct of_device_id mdio_gpio_of_match[] = {
+ { .compatible = "virtual,mdio-gpio", },
+ { /* sentinel */ }
+};
+
+static struct platform_driver mdio_gpio_driver = {
+ .probe = mdio_gpio_probe,
+ .remove = mdio_gpio_remove,
+ .driver = {
+ .name = "mdio-gpio",
+ .of_match_table = mdio_gpio_of_match,
+ },
+};
+
+module_platform_driver(mdio_gpio_driver);
+
+MODULE_ALIAS("platform:mdio-gpio");
+MODULE_AUTHOR("Laurent Pinchart, Paulius Zaleckas");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Generic driver for MDIO bus emulation using GPIO");
Code Review / kvmfornfv.git / blobdiff