diff options
Diffstat (limited to 'drivers/net/phy/mdio-gpio.c')
| -rw-r--r-- | drivers/net/phy/mdio-gpio.c | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/drivers/net/phy/mdio-gpio.c b/drivers/net/phy/mdio-gpio.c new file mode 100644 index 000000000..53d18150f --- /dev/null +++ b/drivers/net/phy/mdio-gpio.c @@ -0,0 +1,278 @@ +/* + * 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"); |