diff options
Diffstat (limited to '')
| -rw-r--r-- | net/rfkill/rfkill-gpio.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/net/rfkill/rfkill-gpio.c b/net/rfkill/rfkill-gpio.c new file mode 100644 index 000000000..0f8465852 --- /dev/null +++ b/net/rfkill/rfkill-gpio.c @@ -0,0 +1,187 @@ +/* + * Copyright (c) 2011, NVIDIA Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * 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. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#include <linux/gpio.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/rfkill.h> +#include <linux/platform_device.h> +#include <linux/clk.h> +#include <linux/slab.h> +#include <linux/acpi.h> +#include <linux/gpio/consumer.h> + +struct rfkill_gpio_data { + const char *name; + enum rfkill_type type; + struct gpio_desc *reset_gpio; + struct gpio_desc *shutdown_gpio; + + struct rfkill *rfkill_dev; + struct clk *clk; + + bool clk_enabled; +}; + +static int rfkill_gpio_set_power(void *data, bool blocked) +{ + struct rfkill_gpio_data *rfkill = data; + + if (!blocked && !IS_ERR(rfkill->clk) && !rfkill->clk_enabled) + clk_enable(rfkill->clk); + + gpiod_set_value_cansleep(rfkill->shutdown_gpio, !blocked); + gpiod_set_value_cansleep(rfkill->reset_gpio, !blocked); + + if (blocked && !IS_ERR(rfkill->clk) && rfkill->clk_enabled) + clk_disable(rfkill->clk); + + rfkill->clk_enabled = !blocked; + + return 0; +} + +static const struct rfkill_ops rfkill_gpio_ops = { + .set_block = rfkill_gpio_set_power, +}; + +static const struct acpi_gpio_params reset_gpios = { 0, 0, false }; +static const struct acpi_gpio_params shutdown_gpios = { 1, 0, false }; + +static const struct acpi_gpio_mapping acpi_rfkill_default_gpios[] = { + { "reset-gpios", &reset_gpios, 1 }, + { "shutdown-gpios", &shutdown_gpios, 1 }, + { }, +}; + +static int rfkill_gpio_acpi_probe(struct device *dev, + struct rfkill_gpio_data *rfkill) +{ + const struct acpi_device_id *id; + + id = acpi_match_device(dev->driver->acpi_match_table, dev); + if (!id) + return -ENODEV; + + rfkill->type = (unsigned)id->driver_data; + + return devm_acpi_dev_add_driver_gpios(dev, acpi_rfkill_default_gpios); +} + +static int rfkill_gpio_probe(struct platform_device *pdev) +{ + struct rfkill_gpio_data *rfkill; + struct gpio_desc *gpio; + const char *type_name; + int ret; + + rfkill = devm_kzalloc(&pdev->dev, sizeof(*rfkill), GFP_KERNEL); + if (!rfkill) + return -ENOMEM; + + device_property_read_string(&pdev->dev, "name", &rfkill->name); + device_property_read_string(&pdev->dev, "type", &type_name); + + if (!rfkill->name) + rfkill->name = dev_name(&pdev->dev); + + rfkill->type = rfkill_find_type(type_name); + + if (ACPI_HANDLE(&pdev->dev)) { + ret = rfkill_gpio_acpi_probe(&pdev->dev, rfkill); + if (ret) + return ret; + } + + rfkill->clk = devm_clk_get(&pdev->dev, NULL); + + gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_OUT_LOW); + if (IS_ERR(gpio)) + return PTR_ERR(gpio); + + rfkill->reset_gpio = gpio; + + gpio = devm_gpiod_get_optional(&pdev->dev, "shutdown", GPIOD_OUT_LOW); + if (IS_ERR(gpio)) + return PTR_ERR(gpio); + + rfkill->shutdown_gpio = gpio; + + /* Make sure at-least one GPIO is defined for this instance */ + if (!rfkill->reset_gpio && !rfkill->shutdown_gpio) { + dev_err(&pdev->dev, "invalid platform data\n"); + return -EINVAL; + } + + rfkill->rfkill_dev = rfkill_alloc(rfkill->name, &pdev->dev, + rfkill->type, &rfkill_gpio_ops, + rfkill); + if (!rfkill->rfkill_dev) + return -ENOMEM; + + ret = rfkill_register(rfkill->rfkill_dev); + if (ret < 0) + goto err_destroy; + + platform_set_drvdata(pdev, rfkill); + + dev_info(&pdev->dev, "%s device registered.\n", rfkill->name); + + return 0; + +err_destroy: + rfkill_destroy(rfkill->rfkill_dev); + + return ret; +} + +static int rfkill_gpio_remove(struct platform_device *pdev) +{ + struct rfkill_gpio_data *rfkill = platform_get_drvdata(pdev); + + rfkill_unregister(rfkill->rfkill_dev); + rfkill_destroy(rfkill->rfkill_dev); + + return 0; +} + +#ifdef CONFIG_ACPI +static const struct acpi_device_id rfkill_acpi_match[] = { + { "BCM4752", RFKILL_TYPE_GPS }, + { "LNV4752", RFKILL_TYPE_GPS }, + { }, +}; +MODULE_DEVICE_TABLE(acpi, rfkill_acpi_match); +#endif + +static struct platform_driver rfkill_gpio_driver = { + .probe = rfkill_gpio_probe, + .remove = rfkill_gpio_remove, + .driver = { + .name = "rfkill_gpio", + .acpi_match_table = ACPI_PTR(rfkill_acpi_match), + }, +}; + +module_platform_driver(rfkill_gpio_driver); + +MODULE_DESCRIPTION("gpio rfkill"); +MODULE_AUTHOR("NVIDIA"); +MODULE_LICENSE("GPL"); |