diff options
author | Arnd Bergmann <arnd@arndb.de> | 2012-10-04 22:57:00 +0200 |
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committer | Arnd Bergmann <arnd@arndb.de> | 2012-10-04 22:57:51 +0200 |
commit | c37d6154c0b9163c27e53cc1d0be3867b4abd760 (patch) | |
tree | 7a24522c56d1cb284dff1d3c225bbdaba0901bb5 /drivers/net/phy/mdio-mux-mmioreg.c | |
parent | e7a570ff7dff9af6e54ff5e580a61ec7652137a0 (diff) | |
parent | 8a1ab3155c2ac7fbe5f2038d6e26efeb607a1498 (diff) |
Merge branch 'disintegrate-asm-generic' of git://git.infradead.org/users/dhowells/linux-headers into asm-generic
Patches from David Howells <dhowells@redhat.com>:
This is to complete part of the UAPI disintegration for which the
preparatory patches were pulled recently.
Note that there are some fixup patches which are at the base of the
branch aimed at you, plus all arches get the asm-generic branch merged in too.
* 'disintegrate-asm-generic' of git://git.infradead.org/users/dhowells/linux-headers:
UAPI: (Scripted) Disintegrate include/asm-generic
UAPI: Fix conditional header installation handling (notably kvm_para.h on m68k)
c6x: remove c6x signal.h
UAPI: Split compound conditionals containing __KERNEL__ in Arm64
UAPI: Fix the guards on various asm/unistd.h files
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'drivers/net/phy/mdio-mux-mmioreg.c')
-rw-r--r-- | drivers/net/phy/mdio-mux-mmioreg.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/drivers/net/phy/mdio-mux-mmioreg.c b/drivers/net/phy/mdio-mux-mmioreg.c new file mode 100644 index 00000000000..9061ba622ac --- /dev/null +++ b/drivers/net/phy/mdio-mux-mmioreg.c @@ -0,0 +1,171 @@ +/* + * 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/init.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 *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; +} + +static int __devinit 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); + 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); + 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; +} + +static int __devexit 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; +} + +static 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", + .owner = THIS_MODULE, + .of_match_table = mdio_mux_mmioreg_match, + }, + .probe = mdio_mux_mmioreg_probe, + .remove = __devexit_p(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"); |