diff options
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/phy/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/net/phy/Makefile | 1 | ||||
| -rw-r--r-- | drivers/net/phy/mdio-mux-gpio.c | 142 |
3 files changed, 153 insertions, 0 deletions
diff --git a/drivers/net/phy/Kconfig b/drivers/net/phy/Kconfig index 99c0674a5935..944cdfb80fe4 100644 --- a/drivers/net/phy/Kconfig +++ b/drivers/net/phy/Kconfig @@ -144,6 +144,16 @@ config MDIO_BUS_MUX to a parent bus. Switching between child busses is done by device specific drivers. +config MDIO_BUS_MUX_GPIO + tristate "Support for GPIO controlled MDIO bus multiplexers" + depends on OF_GPIO && OF_MDIO + 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 # PHYLIB config MICREL_KS8995MA diff --git a/drivers/net/phy/Makefile b/drivers/net/phy/Makefile index a6b50e7715d0..f51af688ef8b 100644 --- a/drivers/net/phy/Makefile +++ b/drivers/net/phy/Makefile @@ -26,3 +26,4 @@ obj-$(CONFIG_MDIO_OCTEON) += mdio-octeon.o obj-$(CONFIG_MICREL_KS8995MA) += spi_ks8995.o obj-$(CONFIG_AMD_PHY) += amd.o obj-$(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 000000000000..e0cc4ef33dee --- /dev/null +++ b/drivers/net/phy/mdio-mux-gpio.c @@ -0,0 +1,142 @@ +/* + * 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. + * + * Copyright (C) 2011, 2012 Cavium, Inc. + */ + +#include <linux/platform_device.h> +#include <linux/device.h> +#include <linux/of_mdio.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/phy.h> +#include <linux/mdio-mux.h> +#include <linux/of_gpio.h> + +#define DRV_VERSION "1.0" +#define DRV_DESCRIPTION "GPIO controlled MDIO bus multiplexer driver" + +#define MDIO_MUX_GPIO_MAX_BITS 8 + +struct mdio_mux_gpio_state { + int gpio[MDIO_MUX_GPIO_MAX_BITS]; + unsigned int num_gpios; + void *mux_handle; +}; + +static int mdio_mux_gpio_switch_fn(int current_child, int desired_child, + void *data) +{ + int change; + unsigned int n; + struct mdio_mux_gpio_state *s = data; + + if (current_child == desired_child) + return 0; + + change = current_child == -1 ? -1 : current_child ^ desired_child; + + for (n = 0; n < s->num_gpios; n++) { + if (change & 1) + gpio_set_value_cansleep(s->gpio[n], + (desired_child & 1) != 0); + change >>= 1; + desired_child >>= 1; + } + + return 0; +} + +static int __devinit mdio_mux_gpio_probe(struct platform_device *pdev) +{ + enum of_gpio_flags f; + struct mdio_mux_gpio_state *s; + unsigned int num_gpios; + unsigned int n; + int r; + + if (!pdev->dev.of_node) + return -ENODEV; + + num_gpios = of_gpio_count(pdev->dev.of_node); + if (num_gpios == 0 || num_gpios > MDIO_MUX_GPIO_MAX_BITS) + return -ENODEV; + + s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL); + if (!s) + return -ENOMEM; + + s->num_gpios = num_gpios; + + for (n = 0; n < num_gpios; ) { + int gpio = of_get_gpio_flags(pdev->dev.of_node, n, &f); + if (gpio < 0) { + r = (gpio == -ENODEV) ? -EPROBE_DEFER : gpio; + goto err; + } + s->gpio[n] = gpio; + + n++; + + r = gpio_request(gpio, "mdio_mux_gpio"); + if (r) + goto err; + + r = gpio_direction_output(gpio, 0); + if (r) + goto err; + } + + r = mdio_mux_init(&pdev->dev, + mdio_mux_gpio_switch_fn, &s->mux_handle, s); + + if (r == 0) { + pdev->dev.platform_data = s; + return 0; + } +err: + while (n) { + n--; + gpio_free(s->gpio[n]); + } + devm_kfree(&pdev->dev, s); + return r; +} + +static int __devexit mdio_mux_gpio_remove(struct platform_device *pdev) +{ + struct mdio_mux_gpio_state *s = pdev->dev.platform_data; + mdio_mux_uninit(s->mux_handle); + return 0; +} + +static struct of_device_id mdio_mux_gpio_match[] = { + { + .compatible = "mdio-mux-gpio", + }, + { + /* Legacy compatible property. */ + .compatible = "cavium,mdio-mux-sn74cbtlv3253", + }, + {}, +}; +MODULE_DEVICE_TABLE(of, mdio_mux_gpio_match); + +static struct platform_driver mdio_mux_gpio_driver = { + .driver = { + .name = "mdio-mux-gpio", + .owner = THIS_MODULE, + .of_match_table = mdio_mux_gpio_match, + }, + .probe = mdio_mux_gpio_probe, + .remove = __devexit_p(mdio_mux_gpio_remove), +}; + +module_platform_driver(mdio_mux_gpio_driver); + +MODULE_DESCRIPTION(DRV_DESCRIPTION); +MODULE_VERSION(DRV_VERSION); +MODULE_AUTHOR("David Daney"); +MODULE_LICENSE("GPL"); |