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Release 4.7 drivers/net/phy/mdio-mux-mmioreg.c

Directory: drivers/net/phy
/*
 * Simple memory-mapped device MDIO MUX driver
 *
 * Author: Timur Tabi <timur@freescale.com>
 *
 * Copyright 2012 Freescale Semiconductor, Inc.
 *
 * 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/platform_device.h>
#include <linux/device.h>
#include <linux/of_address.h>
#include <linux/of_mdio.h>
#include <linux/module.h>
#include <linux/phy.h>
#include <linux/mdio-mux.h>


struct mdio_mux_mmioreg_state {
	
void *mux_handle;
	
phys_addr_t phys;
	
uint8_t mask;
};

/*
 * MDIO multiplexing switch function
 *
 * This function is called by the mdio-mux layer when it thinks the mdio bus
 * multiplexer needs to switch.
 *
 * 'current_child' is the current value of the mux register (masked via
 * s->mask).
 *
 * 'desired_child' is the value of the 'reg' property of the target child MDIO
 * node.
 *
 * 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_mmioreg_switch_fn(int current_child, int desired_child, void *data) { struct mdio_mux_mmioreg_state *s = data; if (current_child ^ desired_child) { void __iomem *p = ioremap(s->phys, 1); uint8_t x, y; if (!p) return -ENOMEM; x = ioread8(p); y = (x & ~s->mask) | desired_child; if (x != y) { iowrite8((x & ~s->mask) | desired_child, p); pr_debug("%s: %02x -> %02x\n", __func__, x, y); } iounmap(p); } return 0; }

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timur tabitimur tabi12199.18%150.00%
jingoo hanjingoo han10.82%150.00%
Total122100.00%2100.00%


static int mdio_mux_mmioreg_probe(struct platform_device *pdev) { struct device_node *np2, *np = pdev->dev.of_node; struct mdio_mux_mmioreg_state *s; struct resource res; const __be32 *iprop; int len, ret; dev_dbg(&pdev->dev, "probing node %s\n", np->full_name); s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL); if (!s) return -ENOMEM; ret = of_address_to_resource(np, 0, &res); if (ret) { dev_err(&pdev->dev, "could not obtain memory map for node %s\n", np->full_name); return ret; } s->phys = res.start; if (resource_size(&res) != sizeof(uint8_t)) { dev_err(&pdev->dev, "only 8-bit registers are supported\n"); return -EINVAL; } iprop = of_get_property(np, "mux-mask", &len); if (!iprop || len != sizeof(uint32_t)) { dev_err(&pdev->dev, "missing or invalid mux-mask property\n"); return -ENODEV; } if (be32_to_cpup(iprop) > 255) { dev_err(&pdev->dev, "only 8-bit registers are supported\n"); return -EINVAL; } s->mask = be32_to_cpup(iprop); /* * Verify that the 'reg' property of each child MDIO bus does not * set any bits outside of the 'mask'. */ for_each_available_child_of_node(np, np2) { iprop = of_get_property(np2, "reg", &len); if (!iprop || len != sizeof(uint32_t)) { dev_err(&pdev->dev, "mdio-mux child node %s is " "missing a 'reg' property\n", np2->full_name); of_node_put(np2); return -ENODEV; } if (be32_to_cpup(iprop) & ~s->mask) { dev_err(&pdev->dev, "mdio-mux child node %s has " "a 'reg' value with unmasked bits\n", np2->full_name); of_node_put(np2); return -ENODEV; } } ret = mdio_mux_init(&pdev->dev, mdio_mux_mmioreg_switch_fn, &s->mux_handle, s); if (ret) { dev_err(&pdev->dev, "failed to register mdio-mux bus %s\n", np->full_name); return ret; } pdev->dev.platform_data = s; return 0; }

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timur tabitimur tabi37197.38%150.00%
julia lawalljulia lawall102.62%150.00%
Total381100.00%2100.00%


static int mdio_mux_mmioreg_remove(struct platform_device *pdev) { struct mdio_mux_mmioreg_state *s = dev_get_platdata(&pdev->dev); mdio_mux_uninit(s->mux_handle); return 0; }

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timur tabitimur tabi34100.00%1100.00%
Total34100.00%1100.00%

static const struct of_device_id mdio_mux_mmioreg_match[] = { { .compatible = "mdio-mux-mmioreg", }, {}, }; MODULE_DEVICE_TABLE(of, mdio_mux_mmioreg_match); static struct platform_driver mdio_mux_mmioreg_driver = { .driver = { .name = "mdio-mux-mmioreg", .of_match_table = mdio_mux_mmioreg_match, }, .probe = mdio_mux_mmioreg_probe, .remove = mdio_mux_mmioreg_remove, }; module_platform_driver(mdio_mux_mmioreg_driver); MODULE_AUTHOR("Timur Tabi <timur@freescale.com>"); MODULE_DESCRIPTION("Memory-mapped device MDIO MUX driver"); MODULE_LICENSE("GPL v2");

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timur tabitimur tabi64098.16%240.00%
julia lawalljulia lawall101.53%120.00%
jingoo hanjingoo han10.15%120.00%
fabian frederickfabian frederick10.15%120.00%
Total652100.00%5100.00%
Directory: drivers/net/phy
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