From 80427f39565857f78e7199908f4f9a0e72a88000 Mon Sep 17 00:00:00 2001 From: Mike Lockwood Date: Tue, 14 Oct 2008 12:50:16 -0400 Subject: [PATCH] switch: switch class and GPIO drivers. MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit switch: Export symbol switch_set_state. Signed-off-by: Mike Lockwood switch: gpio: Don't call request_irq with interrupts disabled Signed-off-by: Arve Hjønnevåg switch: Use device_create instead of device_create_drvdata. device_create_drvdata is obsolete. Signed-off-by: Arve Hjønnevåg switch_gpio: Add missing #include Change-Id: I6c397e41bbe1457162cc69e31a29db5d9f76fccb Signed-off-by: Mike Lockwood --- drivers/Kconfig | 2 + drivers/Makefile | 1 + drivers/switch/Kconfig | 15 ++++ drivers/switch/Makefile | 4 + drivers/switch/switch_class.c | 174 ++++++++++++++++++++++++++++++++++++++++++ drivers/switch/switch_gpio.c | 172 +++++++++++++++++++++++++++++++++++++++++ include/linux/switch.h | 53 +++++++++++++ 7 files changed, 421 insertions(+) create mode 100644 drivers/switch/Kconfig create mode 100644 drivers/switch/Makefile create mode 100644 drivers/switch/switch_class.c create mode 100644 drivers/switch/switch_gpio.c create mode 100644 include/linux/switch.h diff --git a/drivers/Kconfig b/drivers/Kconfig index 177c7d156933..578ff6c0911c 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -92,6 +92,8 @@ source "drivers/leds/Kconfig" source "drivers/nfc/Kconfig" +source "drivers/switch/Kconfig" + source "drivers/accessibility/Kconfig" source "drivers/infiniband/Kconfig" diff --git a/drivers/Makefile b/drivers/Makefile index 3f135b6fb014..6ca41d75327e 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -96,6 +96,7 @@ obj-$(CONFIG_DMA_ENGINE) += dma/ obj-$(CONFIG_MMC) += mmc/ obj-$(CONFIG_MEMSTICK) += memstick/ obj-$(CONFIG_NEW_LEDS) += leds/ +obj-$(CONFIG_SWITCH) += switch/ obj-$(CONFIG_INFINIBAND) += infiniband/ obj-$(CONFIG_SGI_SN) += sn/ obj-y += firmware/ diff --git a/drivers/switch/Kconfig b/drivers/switch/Kconfig new file mode 100644 index 000000000000..52385914b9ae --- /dev/null +++ b/drivers/switch/Kconfig @@ -0,0 +1,15 @@ +menuconfig SWITCH + tristate "Switch class support" + help + Say Y here to enable switch class support. This allows + monitoring switches by userspace via sysfs and uevent. + +if SWITCH + +config SWITCH_GPIO + tristate "GPIO Swith support" + depends on GENERIC_GPIO + help + Say Y here to enable GPIO based switch support. + +endif # SWITCH diff --git a/drivers/switch/Makefile b/drivers/switch/Makefile new file mode 100644 index 000000000000..f7606ed4a719 --- /dev/null +++ b/drivers/switch/Makefile @@ -0,0 +1,4 @@ +# Switch Class Driver +obj-$(CONFIG_SWITCH) += switch_class.o +obj-$(CONFIG_SWITCH_GPIO) += switch_gpio.o + diff --git a/drivers/switch/switch_class.c b/drivers/switch/switch_class.c new file mode 100644 index 000000000000..e05fc2591147 --- /dev/null +++ b/drivers/switch/switch_class.c @@ -0,0 +1,174 @@ +/* + * drivers/switch/switch_class.c + * + * Copyright (C) 2008 Google, Inc. + * Author: Mike Lockwood + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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. + * +*/ + +#include +#include +#include +#include +#include +#include +#include + +struct class *switch_class; +static atomic_t device_count; + +static ssize_t state_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct switch_dev *sdev = (struct switch_dev *) + dev_get_drvdata(dev); + + if (sdev->print_state) { + int ret = sdev->print_state(sdev, buf); + if (ret >= 0) + return ret; + } + return sprintf(buf, "%d\n", sdev->state); +} + +static ssize_t name_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct switch_dev *sdev = (struct switch_dev *) + dev_get_drvdata(dev); + + if (sdev->print_name) { + int ret = sdev->print_name(sdev, buf); + if (ret >= 0) + return ret; + } + return sprintf(buf, "%s\n", sdev->name); +} + +static DEVICE_ATTR(state, S_IRUGO | S_IWUSR, state_show, NULL); +static DEVICE_ATTR(name, S_IRUGO | S_IWUSR, name_show, NULL); + +void switch_set_state(struct switch_dev *sdev, int state) +{ + char name_buf[120]; + char state_buf[120]; + char *prop_buf; + char *envp[3]; + int env_offset = 0; + int length; + + if (sdev->state != state) { + sdev->state = state; + + prop_buf = (char *)get_zeroed_page(GFP_KERNEL); + if (prop_buf) { + length = name_show(sdev->dev, NULL, prop_buf); + if (length > 0) { + if (prop_buf[length - 1] == '\n') + prop_buf[length - 1] = 0; + snprintf(name_buf, sizeof(name_buf), + "SWITCH_NAME=%s", prop_buf); + envp[env_offset++] = name_buf; + } + length = state_show(sdev->dev, NULL, prop_buf); + if (length > 0) { + if (prop_buf[length - 1] == '\n') + prop_buf[length - 1] = 0; + snprintf(state_buf, sizeof(state_buf), + "SWITCH_STATE=%s", prop_buf); + envp[env_offset++] = state_buf; + } + envp[env_offset] = NULL; + kobject_uevent_env(&sdev->dev->kobj, KOBJ_CHANGE, envp); + free_page((unsigned long)prop_buf); + } else { + printk(KERN_ERR "out of memory in switch_set_state\n"); + kobject_uevent(&sdev->dev->kobj, KOBJ_CHANGE); + } + } +} +EXPORT_SYMBOL_GPL(switch_set_state); + +static int create_switch_class(void) +{ + if (!switch_class) { + switch_class = class_create(THIS_MODULE, "switch"); + if (IS_ERR(switch_class)) + return PTR_ERR(switch_class); + atomic_set(&device_count, 0); + } + + return 0; +} + +int switch_dev_register(struct switch_dev *sdev) +{ + int ret; + + if (!switch_class) { + ret = create_switch_class(); + if (ret < 0) + return ret; + } + + sdev->index = atomic_inc_return(&device_count); + sdev->dev = device_create(switch_class, NULL, + MKDEV(0, sdev->index), NULL, sdev->name); + if (IS_ERR(sdev->dev)) + return PTR_ERR(sdev->dev); + + ret = device_create_file(sdev->dev, &dev_attr_state); + if (ret < 0) + goto err_create_file_1; + ret = device_create_file(sdev->dev, &dev_attr_name); + if (ret < 0) + goto err_create_file_2; + + dev_set_drvdata(sdev->dev, sdev); + sdev->state = 0; + return 0; + +err_create_file_2: + device_remove_file(sdev->dev, &dev_attr_state); +err_create_file_1: + device_destroy(switch_class, MKDEV(0, sdev->index)); + printk(KERN_ERR "switch: Failed to register driver %s\n", sdev->name); + + return ret; +} +EXPORT_SYMBOL_GPL(switch_dev_register); + +void switch_dev_unregister(struct switch_dev *sdev) +{ + device_remove_file(sdev->dev, &dev_attr_name); + device_remove_file(sdev->dev, &dev_attr_state); + device_destroy(switch_class, MKDEV(0, sdev->index)); + dev_set_drvdata(sdev->dev, NULL); +} +EXPORT_SYMBOL_GPL(switch_dev_unregister); + +static int __init switch_class_init(void) +{ + return create_switch_class(); +} + +static void __exit switch_class_exit(void) +{ + class_destroy(switch_class); +} + +module_init(switch_class_init); +module_exit(switch_class_exit); + +MODULE_AUTHOR("Mike Lockwood "); +MODULE_DESCRIPTION("Switch class driver"); +MODULE_LICENSE("GPL"); diff --git a/drivers/switch/switch_gpio.c b/drivers/switch/switch_gpio.c new file mode 100644 index 000000000000..7e9faa211e48 --- /dev/null +++ b/drivers/switch/switch_gpio.c @@ -0,0 +1,172 @@ +/* + * drivers/switch/switch_gpio.c + * + * Copyright (C) 2008 Google, Inc. + * Author: Mike Lockwood + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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. + * +*/ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +struct gpio_switch_data { + struct switch_dev sdev; + unsigned gpio; + const char *name_on; + const char *name_off; + const char *state_on; + const char *state_off; + int irq; + struct work_struct work; +}; + +static void gpio_switch_work(struct work_struct *work) +{ + int state; + struct gpio_switch_data *data = + container_of(work, struct gpio_switch_data, work); + + state = gpio_get_value(data->gpio); + switch_set_state(&data->sdev, state); +} + +static irqreturn_t gpio_irq_handler(int irq, void *dev_id) +{ + struct gpio_switch_data *switch_data = + (struct gpio_switch_data *)dev_id; + + schedule_work(&switch_data->work); + return IRQ_HANDLED; +} + +static ssize_t switch_gpio_print_state(struct switch_dev *sdev, char *buf) +{ + struct gpio_switch_data *switch_data = + container_of(sdev, struct gpio_switch_data, sdev); + const char *state; + if (switch_get_state(sdev)) + state = switch_data->state_on; + else + state = switch_data->state_off; + + if (state) + return sprintf(buf, "%s\n", state); + return -1; +} + +static int gpio_switch_probe(struct platform_device *pdev) +{ + struct gpio_switch_platform_data *pdata = pdev->dev.platform_data; + struct gpio_switch_data *switch_data; + int ret = 0; + + if (!pdata) + return -EBUSY; + + switch_data = kzalloc(sizeof(struct gpio_switch_data), GFP_KERNEL); + if (!switch_data) + return -ENOMEM; + + switch_data->sdev.name = pdata->name; + switch_data->gpio = pdata->gpio; + switch_data->name_on = pdata->name_on; + switch_data->name_off = pdata->name_off; + switch_data->state_on = pdata->state_on; + switch_data->state_off = pdata->state_off; + switch_data->sdev.print_state = switch_gpio_print_state; + + ret = switch_dev_register(&switch_data->sdev); + if (ret < 0) + goto err_switch_dev_register; + + ret = gpio_request(switch_data->gpio, pdev->name); + if (ret < 0) + goto err_request_gpio; + + ret = gpio_direction_input(switch_data->gpio); + if (ret < 0) + goto err_set_gpio_input; + + INIT_WORK(&switch_data->work, gpio_switch_work); + + switch_data->irq = gpio_to_irq(switch_data->gpio); + if (switch_data->irq < 0) { + ret = switch_data->irq; + goto err_detect_irq_num_failed; + } + + ret = request_irq(switch_data->irq, gpio_irq_handler, + IRQF_TRIGGER_LOW, pdev->name, switch_data); + if (ret < 0) + goto err_request_irq; + + /* Perform initial detection */ + gpio_switch_work(&switch_data->work); + + return 0; + +err_request_irq: +err_detect_irq_num_failed: +err_set_gpio_input: + gpio_free(switch_data->gpio); +err_request_gpio: + switch_dev_unregister(&switch_data->sdev); +err_switch_dev_register: + kfree(switch_data); + + return ret; +} + +static int __devexit gpio_switch_remove(struct platform_device *pdev) +{ + struct gpio_switch_data *switch_data = platform_get_drvdata(pdev); + + cancel_work_sync(&switch_data->work); + gpio_free(switch_data->gpio); + switch_dev_unregister(&switch_data->sdev); + kfree(switch_data); + + return 0; +} + +static struct platform_driver gpio_switch_driver = { + .probe = gpio_switch_probe, + .remove = __devexit_p(gpio_switch_remove), + .driver = { + .name = "switch-gpio", + .owner = THIS_MODULE, + }, +}; + +static int __init gpio_switch_init(void) +{ + return platform_driver_register(&gpio_switch_driver); +} + +static void __exit gpio_switch_exit(void) +{ + platform_driver_unregister(&gpio_switch_driver); +} + +module_init(gpio_switch_init); +module_exit(gpio_switch_exit); + +MODULE_AUTHOR("Mike Lockwood "); +MODULE_DESCRIPTION("GPIO Switch driver"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/switch.h b/include/linux/switch.h new file mode 100644 index 000000000000..3e4c748e343a --- /dev/null +++ b/include/linux/switch.h @@ -0,0 +1,53 @@ +/* + * Switch class driver + * + * Copyright (C) 2008 Google, Inc. + * Author: Mike Lockwood + * + * This software is licensed under the terms of the GNU General Public + * License version 2, as published by the Free Software Foundation, and + * may be copied, distributed, and modified under those terms. + * + * 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. + * +*/ + +#ifndef __LINUX_SWITCH_H__ +#define __LINUX_SWITCH_H__ + +struct switch_dev { + const char *name; + struct device *dev; + int index; + int state; + + ssize_t (*print_name)(struct switch_dev *sdev, char *buf); + ssize_t (*print_state)(struct switch_dev *sdev, char *buf); +}; + +struct gpio_switch_platform_data { + const char *name; + unsigned gpio; + + /* if NULL, switch_dev.name will be printed */ + const char *name_on; + const char *name_off; + /* if NULL, "0" or "1" will be printed */ + const char *state_on; + const char *state_off; +}; + +extern int switch_dev_register(struct switch_dev *sdev); +extern void switch_dev_unregister(struct switch_dev *sdev); + +static inline int switch_get_state(struct switch_dev *sdev) +{ + return sdev->state; +} + +extern void switch_set_state(struct switch_dev *sdev, int state); + +#endif /* __LINUX_SWITCH_H__ */ -- 2.11.0