Port Linux version driver to Barebox, to support such device found in various revisions of ZII's VF610 development board.
Signed-off-by: Andrey Smirnov <[email protected]> --- drivers/net/phy/Kconfig | 10 +++ drivers/net/phy/Makefile | 1 + drivers/net/phy/mdio-mux-gpio.c | 147 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 158 insertions(+) create mode 100644 drivers/net/phy/mdio-mux-gpio.c diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig index 08ffd2d45..cda752b65 100644 --- a/drivers/net/phy/Kconfig +++ b/drivers/net/phy/Kconfig @@ -74,6 +74,16 @@ config MDIO_BUS_MUX to a parent bus. Switching between child busses is done by device specific drivers. +config MDIO_BUS_MUX_GPIO + bool "GPIO controlled MDIO bus multiplexers" + depends on OF_GPIO + select MDIO_BUS_MUX + help + This module provides a driver for MDIO bus multiplexers that + are controlled via GPIO lines. The multiplexer connects one of + several child MDIO busses to a parent bus. Child bus + selection is under the control of GPIO lines. + endif endmenu diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile index 89b4b80be..30b20f8ee 100644 --- a/drivers/net/phy/Makefile +++ b/drivers/net/phy/Makefile @@ -11,4 +11,5 @@ obj-$(CONFIG_MDIO_MVEBU) += mdio-mvebu.o obj-$(CONFIG_MDIO_BITBANG) += mdio-bitbang.o obj-$(CONFIG_MDIO_GPIO) += mdio-gpio.o obj-$(CONFIG_MDIO_BUS_MUX) += mdio-mux.o +obj-$(CONFIG_MDIO_BUS_MUX_GPIO) += mdio-mux-gpio.o diff --git a/drivers/net/phy/mdio-mux-gpio.c b/drivers/net/phy/mdio-mux-gpio.c new file mode 100644 index 000000000..221353cbc --- /dev/null +++ b/drivers/net/phy/mdio-mux-gpio.c @@ -0,0 +1,147 @@ +/* + * Copyright (c) 2017 Zodiac Inflight Innovation + * Author: Andrey Smirnov <[email protected]> + * + * Based on analogous code from Linux kernel + * + * Copyright (C) 2011, 2012 Cavium, Inc. + * + * 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. + * + * 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 for more details. + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + */ +#include <common.h> +#include <driver.h> +#include <init.h> +#include <linux/mdio-mux.h> +#include <gpio.h> +#include <of_gpio.h> + + +struct mdio_mux_gpio_state { + struct gpio *gpios; + int gpios_num; +}; + +static void mdio_mux_gpio_set_active(struct mdio_mux_gpio_state *s, + unsigned int mask, int value) +{ + while (mask) { + const int n = __ffs(mask); + mask >>= n + 1; + + if (WARN_ON(n >= s->gpios_num)) + break; + + gpio_set_active(s->gpios[n].gpio, value); + } +} + +static int mdio_mux_gpio_switch_fn(int current_child, int desired_child, + void *data) +{ + if (current_child < 0) + current_child = 0; + + if (current_child != desired_child) { + struct mdio_mux_gpio_state *s = data; + /* + * GPIOs that are set in both current and desired + * states can be left untouched. So we calculate them + * and clear corresponding bits in both states. + */ + const int unchanged = current_child & desired_child; + + current_child &= ~unchanged; + desired_child &= ~unchanged; + + /* + * First step: disable all of the currently selected + * bits that are no loger needed + */ + mdio_mux_gpio_set_active(s, current_child, 0); + /* + * Second step: enable all of the GPIOs that are + * desired to be selected + */ + mdio_mux_gpio_set_active(s, desired_child, 1); + } + + return 0; +} + +static int mdio_mux_gpio_probe(struct device_d *dev) +{ + struct mdio_mux_gpio_state *s; + int i, r; + + s = xzalloc(sizeof(*s)); + + s->gpios_num = of_gpio_count(dev->device_node); + if (s->gpios_num <= 0) { + dev_err(dev, "No GPIOs specified\n"); + r = -EINVAL; + goto free_mem; + } + + s->gpios = xzalloc(s->gpios_num * sizeof(s->gpios[0])); + + for (i = 0; i < s->gpios_num; i++) { + enum of_gpio_flags flags; + + r = of_get_gpio_flags(dev->device_node, i, &flags); + if (!gpio_is_valid(r)) { + r = (r < 0) ? r : -EINVAL; + goto free_mem; + } + + s->gpios[i].gpio = r; + s->gpios[i].label = dev_name(dev); + s->gpios[i].flags = GPIOF_OUT_INIT_INACTIVE; + + if (flags & OF_GPIO_ACTIVE_LOW) + s->gpios[i].flags |= GPIOF_ACTIVE_LOW; + } + + r = gpio_request_array(s->gpios, s->gpios_num); + if (r < 0) + goto free_gpios; + + + r = mdio_mux_init(dev, dev->device_node, + mdio_mux_gpio_switch_fn, s, NULL); + if (r < 0) + goto free_gpios; + + return 0; + +free_gpios: + gpio_free_array(s->gpios, s->gpios_num); +free_mem: + free(s->gpios); + free(s); + return r; +} + +static const struct of_device_id mdio_mux_gpio_match[] = { + { + .compatible = "mdio-mux-gpio", + }, + {}, +}; + +static struct driver_d mdio_mux_gpio_driver = { + .name = "mdio-mux-gpio", + .probe = mdio_mux_gpio_probe, + .of_compatible = mdio_mux_gpio_match, +}; +device_platform_driver(mdio_mux_gpio_driver); -- 2.14.3 _______________________________________________ barebox mailing list [email protected] http://lists.infradead.org/mailman/listinfo/barebox
