drivers: net: phy: mdio-mux: Add support for Generic Mux controls (7865ad65) · Commits · e / devices / android_kernel_fairphone_FP5

drivers/net/phy/Kconfig

+12 −0

Original line number	Diff line number	Diff line
		@@ -87,6 +87,18 @@ config MDIO_BUS_MUX_MMIOREG

		Currently, only 8/16/32 bits registers are supported.

		config MDIO_BUS_MUX_MULTIPLEXER
		tristate "MDIO bus multiplexer using kernel multiplexer subsystem"
		depends on OF
		select MULTIPLEXER
		select MDIO_BUS_MUX
		help
		This module provides a driver for MDIO bus multiplexer
		that is controlled via the kernel multiplexer subsystem. The
		bus multiplexer connects one of several child MDIO busses to
		a parent bus. Child bus selection is under the control of
		the kernel multiplexer subsystem.

		config MDIO_CAVIUM
		tristate

drivers/net/phy/Makefile

+1 −0

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		@@ -29,6 +29,7 @@ obj-$(CONFIG_MDIO_BUS_MUX) += mdio-mux.o
		obj-$(CONFIG_MDIO_BUS_MUX_BCM_IPROC) += mdio-mux-bcm-iproc.o
		obj-$(CONFIG_MDIO_BUS_MUX_GPIO) += mdio-mux-gpio.o
		obj-$(CONFIG_MDIO_BUS_MUX_MMIOREG) += mdio-mux-mmioreg.o
		obj-$(CONFIG_MDIO_BUS_MUX_MULTIPLEXER) += mdio-mux-multiplexer.o
		obj-$(CONFIG_MDIO_CAVIUM) += mdio-cavium.o
		obj-$(CONFIG_MDIO_GPIO) += mdio-gpio.o
		obj-$(CONFIG_MDIO_HISI_FEMAC) += mdio-hisi-femac.o

drivers/net/phy/mdio-mux-multiplexer.c

0 → 100644

+122 −0

Original line number	Diff line number	Diff line
		// SPDX-License-Identifier: GPL-2.0+
		/* MDIO bus multiplexer using kernel multiplexer subsystem
		*
		* Copyright 2019 NXP
		*/

		#include <linux/platform_device.h>
		#include <linux/mdio-mux.h>
		#include <linux/module.h>
		#include <linux/mux/consumer.h>

		struct mdio_mux_multiplexer_state {
		struct mux_control *muxc;
		bool do_deselect;
		void *mux_handle;
		};

		/**
		* mdio_mux_multiplexer_switch_fn - This function is called by the mdio-mux
		* layer when it thinks the mdio bus
		* multiplexer needs to switch.
		* @current_child: current value of the mux register.
		* @desired_child: value of the 'reg' property of the target child MDIO node.
		* @data: Private data used by this switch_fn passed to mdio_mux_init function
		* via mdio_mux_init(.., .., .., .., data, ..).
		*
		* The first time this function is called, current_child == -1.
		* If current_child == desired_child, then the mux is already set to the
		* correct bus.
		*/
		static int mdio_mux_multiplexer_switch_fn(int current_child, int desired_child,
		void *data)
		{
		struct platform_device *pdev;
		struct mdio_mux_multiplexer_state *s;
		int ret = 0;

		pdev = (struct platform_device *)data;
		s = platform_get_drvdata(pdev);

		if (!(current_child ^ desired_child))
		return 0;

		if (s->do_deselect)
		ret = mux_control_deselect(s->muxc);
		if (ret) {
		dev_err(&pdev->dev, "mux_control_deselect failed in %s: %d\n",
		__func__, ret);
		return ret;
		}

		ret = mux_control_select(s->muxc, desired_child);
		if (!ret) {
		dev_dbg(&pdev->dev, "%s %d -> %d\n", __func__, current_child,
		desired_child);
		s->do_deselect = true;
		} else {
		s->do_deselect = false;
		}

		return ret;
		}

		static int mdio_mux_multiplexer_probe(struct platform_device *pdev)
		{
		struct device *dev = &pdev->dev;
		struct mdio_mux_multiplexer_state *s;
		int ret = 0;

		s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
		if (!s)
		return -ENOMEM;

		s->muxc = devm_mux_control_get(dev, NULL);
		if (IS_ERR(s->muxc)) {
		ret = PTR_ERR(s->muxc);
		if (ret != -EPROBE_DEFER)
		dev_err(&pdev->dev, "Failed to get mux: %d\n", ret);
		return ret;
		}

		platform_set_drvdata(pdev, s);

		ret = mdio_mux_init(&pdev->dev, pdev->dev.of_node,
		mdio_mux_multiplexer_switch_fn, &s->mux_handle,
		pdev, NULL);

		return ret;
		}

		static int mdio_mux_multiplexer_remove(struct platform_device *pdev)
		{
		struct mdio_mux_multiplexer_state *s = platform_get_drvdata(pdev);

		mdio_mux_uninit(s->mux_handle);

		if (s->do_deselect)
		mux_control_deselect(s->muxc);

		return 0;
		}

		static const struct of_device_id mdio_mux_multiplexer_match[] = {
		{ .compatible = "mdio-mux-multiplexer", },
		{},
		};
		MODULE_DEVICE_TABLE(of, mdio_mux_multiplexer_match);

		static struct platform_driver mdio_mux_multiplexer_driver = {
		.driver = {
		.name = "mdio-mux-multiplexer",
		.of_match_table = mdio_mux_multiplexer_match,
		},
		.probe = mdio_mux_multiplexer_probe,
		.remove = mdio_mux_multiplexer_remove,
		};

		module_platform_driver(mdio_mux_multiplexer_driver);

		MODULE_DESCRIPTION("MDIO bus multiplexer using kernel multiplexer subsystem");
		MODULE_AUTHOR("Pankaj Bansal <pankaj.bansal@nxp.com>");
		MODULE_LICENSE("GPL");