Some LED devices support two operation modes - torch and flash. This patch provides support for flash LED devices in the LED subsystem by introducing new sysfs attributes and kernel internal interface. The attributes being introduced are: flash_brightness, flash_strobe, flash_timeout, max_flash_timeout, max_flash_brightness, flash_fault, external_strobe, indicator_brightness, max_indicator_brightness, strobe_provider, strobe_providerN, blocking_strobe. All the flash related features are placed in a separate module. The modifications aim to be compatible with V4L2 framework requirements related to the flash devices management. The design assumes that V4L2 sub-device can take of the LED class device control and communicate with it through the kernel internal interface. When V4L2 Flash sub-device file is opened, the LED class device sysfs interface is made unavailable. Signed-off-by: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> Acked-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx> Cc: Bryan Wu <cooloney@xxxxxxxxx> Cc: Richard Purdie <rpurdie@xxxxxxxxx> --- drivers/leds/Kconfig | 13 + drivers/leds/Makefile | 5 + drivers/leds/led-class-flash.c | 715 ++++++++++++++++++++++++++++++++++ drivers/leds/led-class.c | 4 + drivers/leds/led-flash-gpio-mux.c | 102 +++++ drivers/leds/led-flash-manager.c | 698 +++++++++++++++++++++++++++++++++ drivers/leds/led-triggers.c | 5 + drivers/leds/of_led_flash_manager.c | 155 ++++++++ include/linux/led-class-flash.h | 290 ++++++++++++++ include/linux/led-flash-gpio-mux.h | 68 ++++ include/linux/led-flash-manager.h | 121 ++++++ include/linux/leds.h | 4 + include/linux/of_led_flash_manager.h | 80 ++++ 13 files changed, 2260 insertions(+) create mode 100644 drivers/leds/led-class-flash.c create mode 100644 drivers/leds/led-flash-gpio-mux.c create mode 100644 drivers/leds/led-flash-manager.c create mode 100644 drivers/leds/of_led_flash_manager.c create mode 100644 include/linux/led-class-flash.h create mode 100644 include/linux/led-flash-gpio-mux.h create mode 100644 include/linux/led-flash-manager.h create mode 100644 include/linux/of_led_flash_manager.h diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 6784c17..5032c6f 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -19,6 +19,19 @@ config LEDS_CLASS This option enables the led sysfs class in /sys/class/leds. You'll need this to do anything useful with LEDs. If unsure, say N. +config LEDS_CLASS_FLASH + tristate "LED Flash Class Support" + depends on LEDS_CLASS + depends on OF + help + This option enables the flash led sysfs class in /sys/class/leds. + It wrapps LED Class and adds flash LEDs specific sysfs attributes + and kernel internal API to it. It allows also for dynamic routing + of external strobe signals basing on the information provided + in the Device Tree binding. You'll need this to provide support + for the flash related features of a LED device. It can be built + as a module. + comment "LED drivers" config LEDS_88PM860X diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 79c5155..237c5ba 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -2,6 +2,11 @@ # LED Core obj-$(CONFIG_NEW_LEDS) += led-core.o obj-$(CONFIG_LEDS_CLASS) += led-class.o +obj-$(CONFIG_LEDS_CLASS_FLASH) += led-flash.o +led-flash-objs := led-class-flash.o \ + led-flash-manager.o \ + led-flash-gpio-mux.o \ + of_led_flash_manager.o obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o # LED Platform Drivers diff --git a/drivers/leds/led-class-flash.c b/drivers/leds/led-class-flash.c new file mode 100644 index 0000000..607f2d7 --- /dev/null +++ b/drivers/leds/led-class-flash.c @@ -0,0 +1,715 @@ +/* + * LED Flash Class interface + * + * Copyright (C) 2014 Samsung Electronics Co., Ltd. + * Author: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/device.h> +#include <linux/init.h> +#include <linux/leds.h> +#include <linux/led-class-flash.h> +#include <linux/led-flash-manager.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <media/v4l2-flash.h> +#include "leds.h" + +#define has_flash_op(flash, op) \ + (flash && flash->ops->op) + +#define call_flash_op(flash, op, args...) \ + ((has_flash_op(flash, op)) ? \ + (flash->ops->op(flash, args)) : \ + -EINVAL) + +static ssize_t flash_brightness_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + unsigned long state; + ssize_t ret; + + mutex_lock(&led_cdev->led_lock); + + if (led_sysfs_is_locked(led_cdev)) { + ret = -EBUSY; + goto unlock; + } + + ret = kstrtoul(buf, 10, &state); + if (ret) + goto unlock; + + ret = led_set_flash_brightness(flash, state); + if (ret < 0) + goto unlock; + + ret = size; +unlock: + mutex_unlock(&led_cdev->led_lock); + return ret; +} + +static ssize_t flash_brightness_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + + /* no lock needed for this */ + led_update_flash_brightness(flash); + + return sprintf(buf, "%u\n", flash->brightness.val); +} +static DEVICE_ATTR_RW(flash_brightness); + +static ssize_t max_flash_brightness_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + + return sprintf(buf, "%u\n", flash->brightness.max); +} +static DEVICE_ATTR_RO(max_flash_brightness); + +static ssize_t indicator_brightness_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + unsigned long state; + ssize_t ret; + + mutex_lock(&led_cdev->led_lock); + + if (led_sysfs_is_locked(led_cdev)) { + ret = -EBUSY; + goto unlock; + } + + ret = kstrtoul(buf, 10, &state); + if (ret) + goto unlock; + + ret = led_set_indicator_brightness(flash, state); + if (ret < 0) + goto unlock; + + ret = size; +unlock: + mutex_unlock(&led_cdev->led_lock); + return ret; +} + +static ssize_t indicator_brightness_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + + /* no lock needed for this */ + led_update_indicator_brightness(flash); + + return sprintf(buf, "%u\n", flash->indicator_brightness->val); +} +static DEVICE_ATTR_RW(indicator_brightness); + +static ssize_t max_indicator_brightness_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + + return sprintf(buf, "%u\n", flash->indicator_brightness->max); +} +static DEVICE_ATTR_RO(max_indicator_brightness); + +static ssize_t flash_strobe_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + unsigned long state; + ssize_t ret = -EINVAL; + + mutex_lock(&led_cdev->led_lock); + + if (led_sysfs_is_locked(led_cdev)) { + ret = -EBUSY; + goto unlock; + } + + ret = kstrtoul(buf, 10, &state); + if (ret) + goto unlock; + + if (state < 0 || state > 1) { + ret = -EINVAL; + goto unlock; + } + + ret = led_set_flash_strobe(flash, state); + if (ret < 0) + goto unlock; + ret = size; +unlock: + mutex_unlock(&led_cdev->led_lock); + return ret; +} + +static ssize_t flash_strobe_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + bool state; + int ret; + + /* no lock needed for this */ + ret = led_get_flash_strobe(flash, &state); + if (ret < 0) + return ret; + + return sprintf(buf, "%u\n", state); +} +static DEVICE_ATTR_RW(flash_strobe); + +static ssize_t flash_timeout_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + unsigned long flash_timeout; + ssize_t ret; + + mutex_lock(&led_cdev->led_lock); + + if (led_sysfs_is_locked(led_cdev)) { + ret = -EBUSY; + goto unlock; + } + + ret = kstrtoul(buf, 10, &flash_timeout); + if (ret) + goto unlock; + + ret = led_set_flash_timeout(flash, flash_timeout); + if (ret < 0) + goto unlock; + + ret = size; +unlock: + mutex_unlock(&led_cdev->led_lock); + return ret; +} + +static ssize_t flash_timeout_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + + return sprintf(buf, "%u\n", flash->timeout.val); +} +static DEVICE_ATTR_RW(flash_timeout); + +static ssize_t max_flash_timeout_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + + return sprintf(buf, "%u\n", flash->timeout.max); +} +static DEVICE_ATTR_RO(max_flash_timeout); + +static ssize_t flash_fault_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + u32 fault; + int ret; + + ret = led_get_flash_fault(flash, &fault); + if (ret < 0) + return -EINVAL; + + return sprintf(buf, "0x%8.8x\n", fault); +} +static DEVICE_ATTR_RO(flash_fault); + +static ssize_t external_strobe_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + unsigned long external_strobe; + ssize_t ret; + + mutex_lock(&led_cdev->led_lock); + + if (led_sysfs_is_locked(led_cdev)) { + ret = -EBUSY; + goto unlock; + } + + ret = kstrtoul(buf, 10, &external_strobe); + if (ret) + goto unlock; + + if (external_strobe > 1) { + ret = -EINVAL; + goto unlock; + } + + ret = led_set_external_strobe(flash, external_strobe); + if (ret < 0) + goto unlock; + ret = size; +unlock: + mutex_unlock(&led_cdev->led_lock); + return ret; +} + +static ssize_t external_strobe_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + + return sprintf(buf, "%u\n", flash->external_strobe); +} +static DEVICE_ATTR_RW(external_strobe); + +static struct attribute *led_flash_strobe_attrs[] = { + &dev_attr_flash_strobe.attr, + NULL, +}; + +static struct attribute *led_flash_indicator_attrs[] = { + &dev_attr_indicator_brightness.attr, + &dev_attr_max_indicator_brightness.attr, + NULL, +}; + +static struct attribute *led_flash_timeout_attrs[] = { + &dev_attr_flash_timeout.attr, + &dev_attr_max_flash_timeout.attr, + NULL, +}; + +static struct attribute *led_flash_brightness_attrs[] = { + &dev_attr_flash_brightness.attr, + &dev_attr_max_flash_brightness.attr, + NULL, +}; + +static struct attribute *led_flash_external_strobe_attrs[] = { + &dev_attr_external_strobe.attr, + NULL, +}; + +static struct attribute *led_flash_fault_attrs[] = { + &dev_attr_flash_fault.attr, + NULL, +}; + +static struct attribute_group led_flash_strobe_group = { + .attrs = led_flash_strobe_attrs, +}; + +static struct attribute_group led_flash_brightness_group = { + .attrs = led_flash_brightness_attrs, +}; + +static struct attribute_group led_flash_timeout_group = { + .attrs = led_flash_timeout_attrs, +}; + +static struct attribute_group led_flash_indicator_group = { + .attrs = led_flash_indicator_attrs, +}; + +static struct attribute_group led_flash_fault_group = { + .attrs = led_flash_fault_attrs, +}; + +static struct attribute_group led_flash_external_strobe_group = { + .attrs = led_flash_external_strobe_attrs, +}; + +static void led_flash_resume(struct led_classdev *led_cdev) +{ + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + + call_flash_op(flash, flash_brightness_set, flash->brightness.val); + call_flash_op(flash, timeout_set, flash->timeout.val); + call_flash_op(flash, indicator_brightness_set, + flash->indicator_brightness->val); +} + +#ifdef CONFIG_V4L2_FLASH_LED_CLASS +const struct v4l2_flash_ops led_flash_v4l2_ops = { + .torch_brightness_set = led_set_torch_brightness, + .torch_brightness_update = led_update_brightness, + .flash_brightness_set = led_set_flash_brightness, + .flash_brightness_update = led_update_flash_brightness, + .indicator_brightness_set = led_set_indicator_brightness, + .indicator_brightness_update = led_update_indicator_brightness, + .strobe_set = led_set_flash_strobe, + .strobe_get = led_get_flash_strobe, + .timeout_set = led_set_flash_timeout, + .external_strobe_set = led_set_external_strobe, + .fault_get = led_get_flash_fault, + .sysfs_lock = led_sysfs_lock, + .sysfs_unlock = led_sysfs_unlock, +}; + +const struct v4l2_flash_ops *led_get_v4l2_flash_ops(void) +{ + return &led_flash_v4l2_ops; +} +EXPORT_SYMBOL_GPL(led_get_v4l2_flash_ops); +#endif + +static void led_flash_remove_sysfs_groups(struct led_classdev_flash *flash) +{ + struct led_classdev *led_cdev = &flash->led_cdev; + int i; + + for (i = 0; i < LED_FLASH_MAX_SYSFS_GROUPS; ++i) + if (flash->sysfs_groups[i]) + sysfs_remove_group(&led_cdev->dev->kobj, + flash->sysfs_groups[i]); +} + +static int led_flash_create_sysfs_groups(struct led_classdev_flash *flash) +{ + struct led_classdev *led_cdev = &flash->led_cdev; + const struct led_flash_ops *ops = flash->ops; + int ret, num_sysfs_groups = 0; + + memset(flash->sysfs_groups, 0, sizeof(*flash->sysfs_groups) * + LED_FLASH_MAX_SYSFS_GROUPS); + + ret = sysfs_create_group(&led_cdev->dev->kobj, &led_flash_strobe_group); + if (ret < 0) + goto err_create_group; + flash->sysfs_groups[num_sysfs_groups++] = &led_flash_strobe_group; + + if (flash->indicator_brightness) { + ret = sysfs_create_group(&led_cdev->dev->kobj, + &led_flash_indicator_group); + if (ret < 0) + goto err_create_group; + flash->sysfs_groups[num_sysfs_groups++] = + &led_flash_indicator_group; + } + + if (ops->flash_brightness_set) { + ret = sysfs_create_group(&led_cdev->dev->kobj, + &led_flash_brightness_group); + if (ret < 0) + goto err_create_group; + flash->sysfs_groups[num_sysfs_groups++] = + &led_flash_brightness_group; + } + + if (ops->timeout_set) { + ret = sysfs_create_group(&led_cdev->dev->kobj, + &led_flash_timeout_group); + if (ret < 0) + goto err_create_group; + flash->sysfs_groups[num_sysfs_groups++] = + &led_flash_timeout_group; + } + + if (ops->fault_get) { + ret = sysfs_create_group(&led_cdev->dev->kobj, + &led_flash_fault_group); + if (ret < 0) + goto err_create_group; + flash->sysfs_groups[num_sysfs_groups++] = + &led_flash_fault_group; + } + + if (flash->has_external_strobe) { + ret = sysfs_create_group(&led_cdev->dev->kobj, + &led_flash_external_strobe_group); + if (ret < 0) + goto err_create_group; + flash->sysfs_groups[num_sysfs_groups++] = + &led_flash_external_strobe_group; + } + + return 0; + +err_create_group: + led_flash_remove_sysfs_groups(flash); + return ret; +} + +int led_classdev_flash_register(struct device *parent, + struct led_classdev_flash *flash, + struct device_node *node) +{ + struct led_classdev *led_cdev; + const struct led_flash_ops *ops; + int ret = -EINVAL; + + if (!flash) + return -EINVAL; + + led_cdev = &flash->led_cdev; + + /* Torch capability is default for every LED Flash Class device */ + led_cdev->flags |= LED_DEV_CAP_TORCH; + + if (led_cdev->flags & LED_DEV_CAP_FLASH) { + if (!led_cdev->torch_brightness_set) + return -EINVAL; + + ops = flash->ops; + if (!ops || !ops->strobe_set) + return -EINVAL; + + if ((led_cdev->flags & LED_DEV_CAP_INDICATOR) && + (!flash->indicator_brightness || + !ops->indicator_brightness_set)) + return -EINVAL; + + led_cdev->flash_resume = led_flash_resume; + } + + /* Register led class device */ + ret = led_classdev_register(parent, led_cdev); + if (ret < 0) + return -EINVAL; + + /* Register in the flash manager if there is related data to parse */ + if (node) { + ret = led_flash_manager_register_flash(flash, node); + if (ret < 0) + goto err_flash_manager_register; + } + + /* Create flash led specific sysfs attributes */ + ret = led_flash_create_sysfs_groups(flash); + if (ret < 0) + goto err_create_sysfs_groups; + + return 0; + +err_create_sysfs_groups: + led_flash_manager_unregister_flash(flash); +err_flash_manager_register: + led_classdev_unregister(led_cdev); + + return ret; +} +EXPORT_SYMBOL_GPL(led_classdev_flash_register); + +void led_classdev_flash_unregister(struct led_classdev_flash *flash) +{ + led_flash_remove_sysfs_groups(flash); + led_flash_manager_unregister_flash(flash); + led_classdev_unregister(&flash->led_cdev); +} +EXPORT_SYMBOL_GPL(led_classdev_flash_unregister); + +int led_set_flash_strobe(struct led_classdev_flash *flash, bool state) +{ + struct led_classdev *led_cdev = &flash->led_cdev; + int ret = 0; + + if (flash->external_strobe) + return -EBUSY; + + /* strobe can be stopped without flash manager involvement */ + if (!state) + return call_flash_op(flash, strobe_set, state); + + /* + * Flash manager needs to be involved in setting flash + * strobe if there were strobe gates defined in the + * device tree binding. This call blocks the caller for + * the current flash timeout period if state == true and + * the flash led device depends on shared muxes. Locking is + * required for assuring that nobody will reconfigure muxes + * in the meantime. + */ + if ((led_cdev->flags & LED_DEV_CAP_FL_MANAGER)) + ret = led_flash_manager_setup_strobe(flash, false); + else + ret = call_flash_op(flash, strobe_set, true); + + return ret; +} +EXPORT_SYMBOL_GPL(led_set_flash_strobe); + +int led_get_flash_strobe(struct led_classdev_flash *flash, bool *state) +{ + return call_flash_op(flash, strobe_get, state); +} +EXPORT_SYMBOL_GPL(led_get_flash_strobe); + +void led_clamp_align(struct led_flash_setting *s) +{ + u32 v, offset; + + v = s->val + s->step / 2; + v = clamp(v, s->min, s->max); + offset = v - s->min; + offset = s->step * (offset / s->step); + s->val = s->min + offset; +} + +int led_set_flash_timeout(struct led_classdev_flash *flash, u32 timeout) +{ + struct led_classdev *led_cdev = &flash->led_cdev; + struct led_flash_setting *s = &flash->timeout; + int ret = 0; + + s->val = timeout; + led_clamp_align(s); + + if (!(led_cdev->flags & LED_SUSPENDED)) + ret = call_flash_op(flash, timeout_set, s->val); + + return ret; +} +EXPORT_SYMBOL_GPL(led_set_flash_timeout); + +int led_get_flash_fault(struct led_classdev_flash *flash, u32 *fault) +{ + return call_flash_op(flash, fault_get, fault); +} +EXPORT_SYMBOL_GPL(led_get_flash_fault); + +int led_set_external_strobe(struct led_classdev_flash *flash, bool enable) +{ + struct led_classdev *led_cdev = &flash->led_cdev; + int ret; + + if (flash->has_external_strobe) { + /* + * Some flash led devices need altering their register + * settings to start listen to the external strobe signal. + */ + if (has_flash_op(flash, external_strobe_set)) { + ret = call_flash_op(flash, external_strobe_set, enable); + if (ret < 0) + return ret; + } + + flash->external_strobe = enable; + + /* + * Flash manager needs to be involved in setting external + * strobe mode if there were strobe gates defined in the + * device tree binding. This call blocks the caller for + * the current flash timeout period if enable == true and + * the flash led device depends on shared muxes. Locking is + * required for assuring that nobody will reconfigure muxes + * while the flash device is awaiting external strobe signal. + */ + if (enable && (led_cdev->flags & LED_DEV_CAP_FL_MANAGER)) { + ret = led_flash_manager_setup_strobe(flash, true); + if (ret < 0) + return ret; + } + } else if (enable) { + return -EINVAL; + } + + return 0; +} +EXPORT_SYMBOL_GPL(led_set_external_strobe); + +int led_set_flash_brightness(struct led_classdev_flash *flash, + u32 brightness) +{ + struct led_classdev *led_cdev = &flash->led_cdev; + struct led_flash_setting *s = &flash->brightness; + int ret = 0; + + s->val = brightness; + led_clamp_align(s); + + if (!(led_cdev->flags & LED_SUSPENDED)) + ret = call_flash_op(flash, flash_brightness_set, s->val); + + return ret; +} +EXPORT_SYMBOL_GPL(led_set_flash_brightness); + +int led_update_flash_brightness(struct led_classdev_flash *flash) +{ + struct led_flash_setting *s = &flash->brightness; + u32 brightness; + int ret = 0; + + if (has_flash_op(flash, flash_brightness_get)) { + ret = call_flash_op(flash, flash_brightness_get, + &brightness); + if (ret < 0) + return ret; + s->val = brightness; + } + + return ret; +} +EXPORT_SYMBOL_GPL(led_update_flash_brightness); + +int led_set_indicator_brightness(struct led_classdev_flash *flash, + u32 brightness) +{ + struct led_classdev *led_cdev = &flash->led_cdev; + struct led_flash_setting *s = flash->indicator_brightness; + int ret = 0; + + if (!s) + return -EINVAL; + + s->val = brightness; + led_clamp_align(s); + + if (!(led_cdev->flags & LED_SUSPENDED)) + ret = call_flash_op(flash, indicator_brightness_set, s->val); + + return ret; +} +EXPORT_SYMBOL_GPL(led_set_indicator_brightness); + +int led_update_indicator_brightness(struct led_classdev_flash *flash) +{ + struct led_flash_setting *s = flash->indicator_brightness; + u32 brightness; + int ret = 0; + + if (!s) + return -EINVAL; + + if (has_flash_op(flash, indicator_brightness_get)) { + ret = call_flash_op(flash, indicator_brightness_get, + &brightness); + if (ret < 0) + return ret; + s->val = brightness; + } + + return ret; +} +EXPORT_SYMBOL_GPL(led_update_indicator_brightness); + +MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("LED Flash Class Interface"); diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index c17dda0..165a1fb 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -189,6 +189,10 @@ EXPORT_SYMBOL_GPL(led_classdev_suspend); void led_classdev_resume(struct led_classdev *led_cdev) { led_cdev->brightness_set(led_cdev, led_cdev->brightness); + + if (led_cdev->flash_resume) + led_cdev->flash_resume(led_cdev); + led_cdev->flags &= ~LED_SUSPENDED; } EXPORT_SYMBOL_GPL(led_classdev_resume); diff --git a/drivers/leds/led-flash-gpio-mux.c b/drivers/leds/led-flash-gpio-mux.c new file mode 100644 index 0000000..2803fcc --- /dev/null +++ b/drivers/leds/led-flash-gpio-mux.c @@ -0,0 +1,102 @@ +/* + * LED Flash Class gpio mux + * + * Copyright (C) 2014 Samsung Electronics Co., Ltd + * Author: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation." + */ + +#include <linux/gpio.h> +#include <linux/led-flash-gpio-mux.h> +#include <linux/of_gpio.h> +#include <linux/slab.h> + +int led_flash_gpio_mux_select_line(u32 line_id, void *mux) +{ + struct led_flash_gpio_mux *gpio_mux = (struct led_flash_gpio_mux *) mux; + struct led_flash_gpio_mux_selector *sel; + u32 mask = 1; + + /* Setup selectors */ + list_for_each_entry(sel, &gpio_mux->selectors, list) { + gpio_set_value(sel->gpio, !!(line_id & mask)); + mask <<= 1; + } + + return 0; +} +EXPORT_SYMBOL_GPL(led_flash_gpio_mux_select_line); + +/* Create standard gpio mux */ +int led_flash_gpio_mux_create(struct led_flash_gpio_mux **new_mux, + struct device_node *mux_node) +{ + struct led_flash_gpio_mux *mux; + struct led_flash_gpio_mux_selector *sel; + int gpio_num, gpio, ret, i; + char gpio_name[20]; + static int cnt_gpio; + + /* Get the number of mux selectors */ + gpio_num = of_gpio_count(mux_node); + if (gpio_num == 0) + return -EINVAL; + + mux = kzalloc(sizeof(*mux), GFP_KERNEL); + if (!mux) + return -ENOMEM; + + INIT_LIST_HEAD(&mux->selectors); + + /* Request gpios for all selectors */ + for (i = 0; i < gpio_num; ++i) { + gpio = of_get_gpio(mux_node, i); + if (gpio_is_valid(gpio)) { + sprintf(gpio_name, "v4l2_mux selector %d", cnt_gpio++); + ret = gpio_request_one(gpio, GPIOF_DIR_OUT, gpio_name); + if (ret < 0) + goto err_gpio_request; + + /* Add new entry to the gpio selectors list */ + sel = kzalloc(sizeof(*sel), GFP_KERNEL); + if (!sel) { + ret = -ENOMEM; + goto err_gpio_request; + } + sel->gpio = gpio; + + list_add_tail(&sel->list, &mux->selectors); + } else { + ret = -EINVAL; + goto err_gpio_request; + } + + } + + *new_mux = mux; + + return 0; + +err_gpio_request: + led_flash_gpio_mux_release(mux); + + return ret; +} +EXPORT_SYMBOL_GPL(led_flash_gpio_mux_create); + +void led_flash_gpio_mux_release(void *mux) +{ + struct led_flash_gpio_mux *gpio_mux = (struct led_flash_gpio_mux *) mux; + struct led_flash_gpio_mux_selector *sel, *n; + + list_for_each_entry_safe(sel, n, &gpio_mux->selectors, list) { + if (gpio_is_valid(sel->gpio)) + gpio_free(sel->gpio); + kfree(sel); + } + kfree(gpio_mux); +} +EXPORT_SYMBOL_GPL(led_flash_gpio_mux_release); diff --git a/drivers/leds/led-flash-manager.c b/drivers/leds/led-flash-manager.c new file mode 100644 index 0000000..2133277 --- /dev/null +++ b/drivers/leds/led-flash-manager.c @@ -0,0 +1,698 @@ +/* + * LED Flash Manager for maintaining LED Flash Class devices + * along with their corresponding muxex, faciliating dynamic + * reconfiguration of the strobe signal source. + * + * Copyright (C) 2014 Samsung Electronics Co., Ltd + * Author: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation." + */ + +#include <linux/delay.h> +#include <linux/led-class-flash.h> +#include <linux/led-flash-gpio-mux.h> +#include <linux/led-flash-manager.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of_gpio.h> +#include <linux/of_led_flash_manager.h> +#include <linux/slab.h> + +static LIST_HEAD(flash_list); +static LIST_HEAD(mux_bound_list); +static LIST_HEAD(mux_waiting_list); +static DEFINE_MUTEX(fm_lock); + +static ssize_t strobe_provider_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t size) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + unsigned long provider_id; + ssize_t ret; + + mutex_lock(&led_cdev->led_lock); + + if (led_sysfs_is_locked(led_cdev)) { + ret = -EBUSY; + goto unlock; + } + + ret = kstrtoul(buf, 10, &provider_id); + if (ret) + goto unlock; + + if (provider_id > flash->num_strobe_providers - 1) { + ret = -ERANGE; + goto unlock; + } + + flash->strobe_provider_id = provider_id; + + ret = size; +unlock: + mutex_unlock(&led_cdev->led_lock); + return ret; +} + +static ssize_t strobe_provider_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + + return sprintf(buf, "%u\n", flash->strobe_provider_id); +} +static DEVICE_ATTR_RW(strobe_provider); + +static ssize_t available_strobe_providers_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_flash_strobe_provider *provider = + container_of(attr, struct led_flash_strobe_provider, attr); + const char *no_name = "undefined"; + const char *provider_name; + + provider_name = provider->name ? provider->name : + no_name; + + return sprintf(buf, "%s\n", provider_name); +} + +static ssize_t blocking_strobe_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct led_classdev *led_cdev = dev_get_drvdata(dev); + struct led_classdev_flash *flash = lcdev_to_flash(led_cdev); + + return sprintf(buf, "%u\n", !!flash->num_shared_muxes); +} +static DEVICE_ATTR_RO(blocking_strobe); + +static int led_flash_manager_create_providers_attrs( + struct led_classdev_flash *flash) +{ + struct led_flash_strobe_provider *provider; + struct led_classdev *led_cdev = &flash->led_cdev; + int cnt_attr = 0; + int ret; + + list_for_each_entry(provider, &flash->strobe_providers, list) { + provider->attr.show = available_strobe_providers_show; + provider->attr.attr.mode = S_IRUGO; + + sprintf(provider->attr_name, "strobe_provider%d", + cnt_attr++); + provider->attr.attr.name = provider->attr_name; + + sysfs_attr_init(&provider->attr.attr); + + ret = sysfs_create_file(&led_cdev->dev->kobj, + &provider->attr.attr); + if (ret < 0) + goto error_create_attr; + + provider->attr_registered = true; + } + + /* + * strobe_provider attribute is required only if there have been more + * than one strobe source defined for the LED Flash Class device. + */ + if (cnt_attr > 1) { + ret = sysfs_create_file(&led_cdev->dev->kobj, + &dev_attr_strobe_provider.attr); + if (ret < 0) + goto error_create_attr; + } + + return 0; + +error_create_attr: + list_for_each_entry(provider, &flash->strobe_providers, list) { + if (!provider->attr_registered) + break; + sysfs_remove_file(&led_cdev->dev->kobj, &provider->attr.attr); + } + + return ret; +} + +static void led_flash_manager_remove_providers_attrs( + struct led_classdev_flash *flash) +{ + struct led_flash_strobe_provider *provider; + struct led_classdev *led_cdev = &flash->led_cdev; + int cnt_attr = 0; + + list_for_each_entry(provider, &flash->strobe_providers, list) { + if (!provider->attr_registered) + break; + sysfs_remove_file(&led_cdev->dev->kobj, &provider->attr.attr); + provider->attr_registered = false; + ++cnt_attr; + } + + /* + * If there was more than one strobe_providerN attr to remove + * than there is also strobe_provider attr to remove. + */ + if (cnt_attr > 1) + sysfs_remove_file(&led_cdev->dev->kobj, + &dev_attr_strobe_provider.attr); +} + +/* Return mux associated with gate */ +static struct led_flash_mux *led_flash_manager_get_mux_by_gate( + struct led_flash_strobe_gate *gate, + struct list_head *mux_list) +{ + struct led_flash_mux *mux; + + list_for_each_entry(mux, mux_list, list) + if (mux->node == gate->mux_node) + return mux; + + return NULL; +} + +/* Setup all muxes in the gate list */ +static int led_flash_manager_setup_muxes(struct led_classdev_flash *flash, + struct list_head *gate_list) +{ + struct led_classdev *led_cdev = &flash->led_cdev; + struct led_flash_strobe_gate *gate; + struct led_flash_mux *mux; + struct device *dev = led_cdev->dev->parent; + int ret = 0; + + list_for_each_entry(gate, gate_list, list) { + mux = led_flash_manager_get_mux_by_gate(gate, &mux_bound_list); + if (!mux) { + dev_err(dev, "Flash mux not bound (%s)\n", + gate->mux_node->name); + return -ENODEV; + } + + ret = mux->ops->select_line(gate->line_id, + mux->private_data); + } + + return ret; +} + +/* + * Setup all muxes required to open the route + * to the external strobe signal provider + */ +static int led_flash_manager_select_strobe_provider( + struct led_classdev_flash *flash, + int provider_id) +{ + struct led_flash_strobe_provider *provider; + int ret, provider_cnt = 0; + + list_for_each_entry(provider, &flash->strobe_providers, list) + if (provider_cnt++ == provider_id) { + ret = led_flash_manager_setup_muxes(flash, + &provider->strobe_gates); + return ret; + } + + return -EINVAL; +} + +/* + * Setup all muxes required to open the route + * either to software or external strobe source. + */ +static int led_flash_manager_set_external_strobe( + struct led_classdev_flash *flash, + bool external) +{ + int ret; + + if (external) + ret = led_flash_manager_select_strobe_provider(flash, + flash->strobe_provider_id); + else + ret = led_flash_manager_setup_muxes(flash, + &flash->software_strobe_gates); + + return ret; +} + +/* Notify flash manager that async mux is available. */ +int led_flash_manager_bind_async_mux(struct led_flash_mux *async_mux) +{ + struct led_flash_mux *mux; + bool mux_found = false; + int ret = 0; + + if (!async_mux) + return -EINVAL; + + mutex_lock(&fm_lock); + + /* + * Check whether the LED Flash Class device using this + * mux has been already registered in the flash manager. + */ + list_for_each_entry(mux, &mux_waiting_list, list) + if (async_mux->node == mux->node) { + /* Move the mux to the bound muxes list */ + + list_move(&mux->list, &mux_bound_list); + mux_found = true; + + if (!try_module_get(async_mux->owner)) { + ret = -ENODEV; + goto unlock; + } + + break; + } + + if (!mux_found) { + /* This is a new mux - create its representation */ + mux = kzalloc(sizeof(*mux), GFP_KERNEL); + if (!mux) { + ret = -ENOMEM; + goto unlock; + } + + INIT_LIST_HEAD(&mux->refs); + + /* Add the mux to the bound list. */ + list_add(&mux->list, &mux_bound_list); + } + + mux->ops = async_mux->ops; + mux->node = async_mux->node; + mux->owner = async_mux->owner; + +unlock: + mutex_unlock(&fm_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(led_flash_manager_bind_async_mux); + +int led_flash_manager_unbind_async_mux(struct device_node *mux_node) +{ + struct led_flash_mux *mux; + int ret = -ENODEV; + + mutex_lock(&fm_lock); + + /* + * Mux can be unbound only when is not used by any + * flash led device, otherwise this is erroneous call. + */ + list_for_each_entry(mux, &mux_waiting_list, list) + if (mux->node == mux_node) { + list_move(&mux->list, &mux_waiting_list); + ret = 0; + break; + } + + mutex_unlock(&fm_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(led_flash_manager_unbind_async_mux); + +struct led_flash_mux_ops gpio_mux_ops = { + .select_line = led_flash_gpio_mux_select_line, + .release_private_data = led_flash_gpio_mux_release, +}; + +static int __add_mux_ref(struct led_flash_mux_ref *ref, + struct led_flash_mux *mux) +{ + struct led_flash_mux_ref *r; + int ret; + + /* + * A flash can be associated with a mux through + * more than one gate - increment mux reference + * count in such a case. + */ + list_for_each_entry(r, &mux->refs, list) + if (r->flash == ref->flash) + return 0; + + /* protect async mux against rmmod */ + if (mux->owner) { + ret = try_module_get(mux->owner); + if (ret < 0) + return ret; + } + + list_add(&ref->list, &mux->refs); + ++mux->num_refs; + + if (mux->num_refs == 2) { + list_for_each_entry(r, &mux->refs, list) { + ++r->flash->num_shared_muxes; + } + return 0; + } + + if (mux->num_refs > 2) + ++ref->flash->num_shared_muxes; + + return 0; +} + +static void __remove_mux_ref(struct led_flash_mux_ref *ref, + struct led_flash_mux *mux) +{ + struct led_flash_mux_ref *r; + + /* decrement async mux refcount */ + if (mux->owner) + module_put(mux->owner); + + list_del(&ref->list); + --mux->num_refs; + + if (mux->num_refs == 1) { + r = list_first_entry(&mux->refs, struct led_flash_mux_ref, + list); + --r->flash->num_shared_muxes; + return; + } + + if (mux->num_refs > 1) + --ref->flash->num_shared_muxes; +} + +/* + * Parse mux node and add the mux it refers to either to waiting + * or bound list depending on the mux type (gpio or asynchronous). + */ +static int led_flash_manager_parse_mux_node(struct led_classdev_flash *flash, + struct led_flash_strobe_gate *gate) +{ + struct led_flash_mux *mux; + struct device_node *async_mux_node; + struct led_flash_gpio_mux *gpio_mux; + struct led_flash_mux_ref *ref; + int ret = -EINVAL; + + /* Create flash ref to be added to the mux references list */ + ref = kzalloc(sizeof(*ref), GFP_KERNEL); + if (!ref) + return -ENOMEM; + ref->flash = flash; + + /* if this is async mux update gate's mux_node accordingly */ + async_mux_node = of_parse_phandle(gate->mux_node, "mux-async", 0); + if (async_mux_node) + gate->mux_node = async_mux_node; + + /* Check if the mux isn't already on waiting list */ + list_for_each_entry(mux, &mux_waiting_list, list) + if (mux->node == gate->mux_node) + return __add_mux_ref(ref, mux); + + /* Check if the mux isn't already on bound list */ + list_for_each_entry(mux, &mux_bound_list, list) + if (mux->node == gate->mux_node) + return __add_mux_ref(ref, mux); + + /* This is a new mux - create its representation */ + mux = kzalloc(sizeof(*mux), GFP_KERNEL); + if (!mux) + return -ENOMEM; + + mux->node = gate->mux_node; + + INIT_LIST_HEAD(&mux->refs); + + /* Increment reference count */ + ret = __add_mux_ref(ref, mux); + if (ret < 0) + return ret; + + /* + * Check if this mux has its own driver + * or this is standard gpio mux. + */ + if (async_mux_node) { + /* Add async mux to the waiting list */ + list_add(&mux->list, &mux_waiting_list); + } else { + /* Create default gpio mux */ + ret = led_flash_gpio_mux_create(&gpio_mux, gate->mux_node); + if (ret < 0) + goto err_gpio_mux_init; + + /* Register gpio mux device */ + mux->private_data = gpio_mux; + mux->ops = &gpio_mux_ops; + list_add(&mux->list, &mux_bound_list); + } + + return 0; + +err_gpio_mux_init: + kfree(mux); + kfree(ref); + + return ret; +} + +static void led_flash_manager_release_mux(struct led_flash_mux *mux) +{ + if (mux->ops->release_private_data) { + if (mux->ops->release_private_data) + mux->ops->release_private_data(mux->private_data); + list_del(&mux->list); + kfree(mux); + } +} + +static void led_flash_manager_remove_flash_refs( + struct led_classdev_flash *flash) +{ + struct led_flash_mux_ref *ref, *rn; + struct led_flash_mux *mux, *mn; + + /* + * Remove references to the flash from + * all the muxes on the list. + */ + list_for_each_entry_safe(mux, mn, &mux_bound_list, list) + /* Seek for matching flash ref */ + list_for_each_entry_safe(ref, rn, &mux->refs, list) + if (ref->flash == flash) { + /* Decrement reference count */ + __remove_mux_ref(ref, mux); + kfree(ref); + /* + * Release mux if there are no more + * references pointing to it. + */ + if (list_empty(&mux->refs)) + led_flash_manager_release_mux(mux); + } +} + +int led_flash_manager_setup_strobe(struct led_classdev_flash *flash, + bool external) +{ + u32 flash_timeout = flash->timeout.val / 1000; + int ret; + + mutex_lock(&fm_lock); + + /* Setup muxes */ + ret = led_flash_manager_set_external_strobe(flash, external); + if (ret < 0) + goto unlock; + + /* + * Trigger software strobe under flash manager lock + * to make sure that nobody will reconfigure muxes + * in the meantime. + */ + if (!external) { + ret = flash->ops->strobe_set(flash, true); + if (ret < 0) + goto unlock; + } + + /* + * Hold lock for the time of strobing if the + * LED Flash Class device depends on shared muxes. + */ + if (flash->num_shared_muxes > 0) { + msleep(flash_timeout); + /* + * external strobe is turned on only for the time of + * this call if there are shared muxes involved + * in strobe signal routing. + */ + flash->external_strobe = false; + } + +unlock: + mutex_unlock(&fm_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(led_flash_manager_setup_strobe); + +int led_flash_manager_create_sysfs_attrs(struct led_classdev_flash *flash) +{ + struct led_classdev *led_cdev = &flash->led_cdev; + int ret; + + /* + * Create sysfs attribtue for indicating if activation of + * software or external flash strobe will block the caller. + */ + sysfs_attr_init(&dev_attr_blocking_strobe.attr); + ret = sysfs_create_file(&led_cdev->dev->kobj, + &dev_attr_blocking_strobe.attr); + if (ret < 0) + return ret; + + /* Create strobe_providerN attributes */ + ret = led_flash_manager_create_providers_attrs(flash); + if (ret < 0) + goto err_create_provider_attrs; + + return 0; + +err_create_provider_attrs: + sysfs_remove_file(&led_cdev->dev->kobj, + &dev_attr_blocking_strobe.attr); + + return ret; +} + +void led_flash_manager_remove_sysfs_attrs(struct led_classdev_flash *flash) +{ + struct led_classdev *led_cdev = &flash->led_cdev; + + led_flash_manager_remove_providers_attrs(flash); + sysfs_remove_file(&led_cdev->dev->kobj, + &dev_attr_blocking_strobe.attr); +} + +int led_flash_manager_register_flash(struct led_classdev_flash *flash, + struct device_node *node) +{ + struct led_flash_strobe_provider *provider; + struct led_flash_strobe_gate *gate; + struct led_classdev_flash *fl; + struct led_classdev *led_cdev = &flash->led_cdev; + int ret = 0; + + if (!flash || !node) + return -EINVAL; + + mutex_lock(&fm_lock); + + /* Don't allow to register the same flash more than once */ + list_for_each_entry(fl, &flash_list, list) + if (fl == flash) + goto unlock; + + INIT_LIST_HEAD(&flash->software_strobe_gates); + INIT_LIST_HEAD(&flash->strobe_providers); + + ret = of_led_flash_manager_parse_dt(flash, node); + if (ret < 0) + goto unlock; + + /* + * Register mux devices declared by the flash device + * if they have not been yet known to the flash manager. + */ + list_for_each_entry(gate, &flash->software_strobe_gates, list) { + ret = led_flash_manager_parse_mux_node(flash, gate); + if (ret < 0) + goto err_parse_mux_node; + } + + list_for_each_entry(provider, &flash->strobe_providers, list) { + list_for_each_entry(gate, &provider->strobe_gates, list) { + ret = led_flash_manager_parse_mux_node(flash, gate); + if (ret < 0) + goto err_parse_mux_node; + } + ++flash->num_strobe_providers; + } + + /* + * It doesn't make sense to register in the flash manager + * if there are no strobe providers defined. + */ + if (flash->num_strobe_providers == 0) + goto unlock; + + led_cdev->flags |= LED_DEV_CAP_FL_MANAGER; + flash->has_external_strobe = true; + flash->strobe_provider_id = 0; + + ret = led_flash_manager_create_sysfs_attrs(flash); + if (ret < 0) + goto err_parse_mux_node; + + /* Add flash to the list of flashes maintained by the flash manager. */ + list_add_tail(&flash->list, &flash_list); + + mutex_unlock(&fm_lock); + + return ret; + +err_parse_mux_node: + led_flash_manager_remove_flash_refs(flash); + of_led_flash_manager_release_dt_data(flash); +unlock: + mutex_unlock(&fm_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(led_flash_manager_register_flash); + +void led_flash_manager_unregister_flash(struct led_classdev_flash *flash) +{ + struct led_classdev_flash *fl, *n; + bool found_flash = false; + + mutex_lock(&fm_lock); + + /* Remove flash from the list, if found */ + list_for_each_entry_safe(fl, n, &flash_list, list) + if (fl == flash) { + found_flash = true; + break; + } + + if (!found_flash) + goto unlock; + + list_del(&fl->list); + + led_flash_manager_remove_sysfs_attrs(flash); + + /* Remove all references to the flash */ + led_flash_manager_remove_flash_refs(flash); + of_led_flash_manager_release_dt_data(flash); + +unlock: + mutex_unlock(&fm_lock); +} +EXPORT_SYMBOL_GPL(led_flash_manager_unregister_flash); + +MODULE_AUTHOR("Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx>"); +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("LED Flash Manager"); diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c index 0545530..e8380bb 100644 --- a/drivers/leds/led-triggers.c +++ b/drivers/leds/led-triggers.c @@ -41,6 +41,11 @@ ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, mutex_lock(&led_cdev->led_lock); + if (led_sysfs_is_locked(led_cdev)) { + ret = -EBUSY; + goto exit_unlock; + } + trigger_name[sizeof(trigger_name) - 1] = '\0'; strncpy(trigger_name, buf, sizeof(trigger_name) - 1); len = strlen(trigger_name); diff --git a/drivers/leds/of_led_flash_manager.c b/drivers/leds/of_led_flash_manager.c new file mode 100644 index 0000000..d22d853 --- /dev/null +++ b/drivers/leds/of_led_flash_manager.c @@ -0,0 +1,155 @@ +/* + * LED flash manager of helpers. + * + * Copyright (C) 2014 Samsung Electronics Co., Ltd + * Author: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation." + */ + +#include <linux/device.h> +#include <linux/led-class-flash.h> +#include <linux/of.h> +#include <linux/of_led_flash_manager.h> +#include <linux/slab.h> + +static int __parse_strobe_gate_node(struct led_classdev_flash *flash, + struct device_node *node, + struct list_head *gates) +{ + struct device_node *mux_node, *subnode; + struct led_flash_strobe_gate *gate; + struct led_classdev *led_cdev = &flash->led_cdev; + u32 line_id; + int ret, num_gates = 0; + + /* Get node mux node */ + mux_node = of_parse_phandle(node, "mux", 0); + if (!mux_node) + return -EINVAL; + + /* Get the value the mux has to be written to open the gate */ + ret = of_property_read_u32(node, "mux-line-id", &line_id); + if (ret < 0) + return ret; + + gate = kzalloc(sizeof(*gate), GFP_KERNEL); + if (!gate) + return -ENOMEM; + + gate->mux_node = mux_node; + gate->line_id = line_id; + list_add_tail(&gate->list, gates); + + /* Parse nested gate nodes */ + for_each_available_child_of_node(node, subnode) { + if (!of_node_ncmp(subnode->name, "gate", 4)) { + ret = __parse_strobe_gate_node(flash, subnode, gates); + if (ret < 0) { + dev_dbg(led_cdev->dev->parent, + "Failed to parse gate node (%d)\n", + ret); + goto err_parse_gate; + } + + if (++num_gates > 1) { + dev_dbg(led_cdev->dev->parent, + "Only one available child gate is allowed.\n"); + ret = -EINVAL; + goto err_parse_gate; + } + } + } + + return 0; + +err_parse_gate: + kfree(gate); + + return ret; +} + +static int __parse_strobe_provider_node(struct led_classdev_flash *flash, + struct device_node *node) +{ + struct device_node *provider_node; + struct led_flash_strobe_provider *provider; + int ret; + + /* Create strobe provider representation */ + provider = kzalloc(sizeof(*provider), GFP_KERNEL); + if (!provider) + return -ENOMEM; + + /* Get phandle of the device generating strobe source signal */ + provider_node = of_parse_phandle(node, "strobe-provider", 0); + + /* provider property may be absent */ + if (provider_node) { + /* Use compatible property as a strobe provider name */ + ret = of_property_read_string(provider_node, "compatible", + (const char **) &provider->name); + if (ret < 0) + goto err_read_name; + } + + INIT_LIST_HEAD(&provider->strobe_gates); + + list_add_tail(&provider->list, &flash->strobe_providers); + + ret = __parse_strobe_gate_node(flash, node, &provider->strobe_gates); + if (ret < 0) + goto err_read_name; + + return 0; + +err_read_name: + kfree(provider); + + return ret; +} + +int of_led_flash_manager_parse_dt(struct led_classdev_flash *flash, + struct device_node *node) +{ + struct device_node *subnode; + int ret; + + for_each_available_child_of_node(node, subnode) { + if (!of_node_cmp(subnode->name, "gate-software-strobe")) { + ret = __parse_strobe_gate_node(flash, subnode, + &flash->software_strobe_gates); + if (ret < 0) + return ret; + } + if (!of_node_ncmp(subnode->name, "gate-external-strobe", 20)) { + ret = __parse_strobe_provider_node(flash, subnode); + if (ret < 0) + return ret; + } + } + + return 0; +} +EXPORT_SYMBOL_GPL(of_led_flash_manager_parse_dt); + +void of_led_flash_manager_release_dt_data(struct led_classdev_flash *flash) +{ + struct list_head *gate_list; + struct led_flash_strobe_gate *gate, *gn; + struct led_flash_strobe_provider *provider, *sn; + + gate_list = &flash->software_strobe_gates; + list_for_each_entry_safe(gate, gn, gate_list, list) + kfree(gate); + + list_for_each_entry_safe(provider, sn, &flash->strobe_providers, list) { + list_for_each_entry_safe(gate, gn, &provider->strobe_gates, + list) + kfree(gate); + kfree(provider); + } +} +EXPORT_SYMBOL_GPL(of_led_flash_manager_release_dt_data); diff --git a/include/linux/led-class-flash.h b/include/linux/led-class-flash.h new file mode 100644 index 0000000..6ed7e8a --- /dev/null +++ b/include/linux/led-class-flash.h @@ -0,0 +1,290 @@ +/* + * LED Flash Class interface + * + * Copyright (C) 2014 Samsung Electronics Co., Ltd. + * Author: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ +#ifndef __LINUX_FLASH_LEDS_H_INCLUDED +#define __LINUX_FLASH_LEDS_H_INCLUDED + +#include <linux/leds.h> + +struct v4l2_flash_ops; +struct led_classdev_flash; +struct device_node; + +/* + * Supported led fault bits - must be kept in synch + * with V4L2_FLASH_FAULT bits. + */ +#define LED_FAULT_OVER_VOLTAGE V4L2_FLASH_FAULT_OVER_VOLTAGE +#define LED_FAULT_TIMEOUT V4L2_FLASH_FAULT_TIMEOUT +#define LED_FAULT_OVER_TEMPERATURE V4L2_FLASH_FAULT_OVER_TEMPERATURE +#define LED_FAULT_SHORT_CIRCUIT V4L2_FLASH_FAULT_SHORT_CIRCUIT +#define LED_FAULT_OVER_CURRENT V4L2_FLASH_FAULT_OVER_CURRENT +#define LED_FAULT_INDICATOR V4L2_FLASH_FAULT_INDICATOR +#define LED_FAULT_UNDER_VOLTAGE V4L2_FLASH_FAULT_UNDER_VOLTAGE +#define LED_FAULT_INPUT_VOLTAGE V4L2_FLASH_FAULT_INPUT_VOLTAGE +#define LED_FAULT_LED_OVER_TEMPERATURE V4L2_FLASH_OVER_TEMPERATURE + +#define LED_FLASH_MAX_SYSFS_GROUPS 6 + +struct led_flash_ops { + /* set flash brightness */ + int (*flash_brightness_set)(struct led_classdev_flash *flash, + u32 brightness); + /* get flash brightness */ + int (*flash_brightness_get)(struct led_classdev_flash *flash, + u32 *brightness); + /* set flash indicator brightness */ + int (*indicator_brightness_set)(struct led_classdev_flash *flash, + u32 brightness); + /* get flash indicator brightness */ + int (*indicator_brightness_get)(struct led_classdev_flash *flash, + u32 *brightness); + /* set flash strobe state */ + int (*strobe_set)(struct led_classdev_flash *flash, bool state); + /* get flash strobe state */ + int (*strobe_get)(struct led_classdev_flash *flash, bool *state); + /* set flash timeout */ + int (*timeout_set)(struct led_classdev_flash *flash, u32 timeout); + /* setup the device to strobe the flash upon a pin state assertion */ + int (*external_strobe_set)(struct led_classdev_flash *flash, + bool enable); + /* get the flash LED fault */ + int (*fault_get)(struct led_classdev_flash *flash, u32 *fault); +}; + +/* + * Current value of a flash setting along + * with its constraints. + */ +struct led_flash_setting { + /* maximum allowed value */ + u32 min; + /* maximum allowed value */ + u32 max; + /* step value */ + u32 step; + /* current value */ + u32 val; +}; + +/* + * Aggregated flash settings - designed for ease + * of passing initialization data to the clients + * wrapping a LED Flash class device. + */ +struct led_flash_config { + struct led_flash_setting torch_brightness; + struct led_flash_setting flash_brightness; + struct led_flash_setting indicator_brightness; + struct led_flash_setting flash_timeout; + u32 flash_faults; +}; + +struct led_classdev_flash { + /* led-flash-manager uses it to link flashes */ + struct list_head list; + /* led class device */ + struct led_classdev led_cdev; + /* flash led specific ops */ + const struct led_flash_ops *ops; + + /* flash sysfs groups */ + struct attribute_group *sysfs_groups[LED_FLASH_MAX_SYSFS_GROUPS]; + + /* flash brightness value in microamperes along with its constraints */ + struct led_flash_setting brightness; + + /* timeout value in microseconds along with its constraints */ + struct led_flash_setting timeout; + + /* + * Indicator brightness value in microamperes along with + * its constraints - this is an optional setting and must + * be allocated by the driver if the device supports privacy + * indicator led. + */ + struct led_flash_setting *indicator_brightness; + + /* + * determines if a device supports external + * flash strobe sources + */ + bool has_external_strobe; + + /* If true the flash led is strobed from external source */ + bool external_strobe; + + /* Flash manager data */ + /* Strobe signals topology data */ + struct list_head software_strobe_gates; + struct list_head strobe_providers; + + /* identifier of the selected strobe signal provider */ + int strobe_provider_id; + + /* number of defined strobe providers */ + int num_strobe_providers; + + /* + * number of muxes that this device shares + * with other LED Flash Class devices. + */ + int num_shared_muxes; +}; + +static inline struct led_classdev_flash *lcdev_to_flash( + struct led_classdev *lcdev) +{ + return container_of(lcdev, struct led_classdev_flash, led_cdev); +} + +/** + * led_classdev_flash_register - register a new object of led_classdev_flash class + with support for flash LEDs + * @parent: the device to register + * @flash: the led_classdev_flash structure for this device + * @node: device tree node of the LED Flash Class device - it must be + initialized if the device is to be registered in the flash manager + * + * Returns: 0 on success or negative error value on failure + */ +int led_classdev_flash_register(struct device *parent, + struct led_classdev_flash *flash, + struct device_node *node); + +/** + * led_classdev_flash_unregister - unregisters an object of led_classdev_flash class + with support for flash LEDs + * @flash: the flash led device to unregister + * + * Unregisters a previously registered via led_classdev_flash_register object + */ +void led_classdev_flash_unregister(struct led_classdev_flash *flash); + +/** + * led_set_flash_strobe - setup flash strobe + * @flash: the flash LED to set strobe on + * @state: 1 - strobe flash, 0 - stop flash strobe + * + * Setup flash strobe - trigger flash strobe + * + * Returns: 0 on success or negative error value on failure + */ +extern int led_set_flash_strobe(struct led_classdev_flash *flash, + bool state); + +/** + * led_get_flash_strobe - get flash strobe status + * @flash: the LED to query + * @state: 1 - flash is strobing, 0 - flash is off + * + * Check whether the flash is strobing at the moment or not. + * +u* Returns: 0 on success or negative error value on failure + */ +extern int led_get_flash_strobe(struct led_classdev_flash *flash, + bool *state); +/** + * led_set_flash_brightness - set flash LED brightness + * @flash: the LED to set + * @brightness: the brightness to set it to + * + * Returns: 0 on success or negative error value on failure + * + * Set a flash LED's brightness. + */ +extern int led_set_flash_brightness(struct led_classdev_flash *flash, + u32 brightness); + +/** + * led_update_flash_brightness - update flash LED brightness + * @flash: the LED to query + * + * Get a flash LED's current brightness and update led_flash->brightness + * member with the obtained value. + * + * Returns: 0 on success or negative error value on failure + */ +extern int led_update_flash_brightness(struct led_classdev_flash *flash); + +/** + * led_set_flash_timeout - set flash LED timeout + * @flash: the LED to set + * @timeout: the flash timeout to set it to + * + * Set the flash strobe duration. The duration set by the driver + * is returned in the timeout argument and may differ from the + * one that was originally passed. + * + * Returns: 0 on success or negative error value on failure + */ +extern int led_set_flash_timeout(struct led_classdev_flash *flash, + u32 timeout); + +/** + * led_get_flash_fault - get the flash LED fault + * @flash: the LED to query + * @fault: bitmask containing flash faults + * + * Get the flash LED fault. + * + * Returns: 0 on success or negative error value on failure + */ +extern int led_get_flash_fault(struct led_classdev_flash *flash, + u32 *fault); + +/** + * led_set_external_strobe - set the flash LED external_strobe mode + * @flash: the LED to set + * @enable: the state to set it to + * + * Enable/disable strobing the flash LED with use of external source + * + Returns: 0 on success or negative error value on failure + */ +extern int led_set_external_strobe(struct led_classdev_flash *flash, + bool enable); + +/** + * led_set_indicator_brightness - set indicator LED brightness + * @flash: the LED to set + * @brightness: the brightness to set it to + * + * Set an indicator LED's brightness. + * + * Returns: 0 on success or negative error value on failure + */ +extern int led_set_indicator_brightness(struct led_classdev_flash *flash, + u32 led_brightness); + +/** + * led_update_indicator_brightness - update flash indicator LED brightness + * @flash: the LED to query + * + * Get a flash indicator LED's current brightness and update + * led_flash->indicator_brightness member with the obtained value. + * + * Returns: 0 on success or negative error value on failure + */ +extern int led_update_indicator_brightness(struct led_classdev_flash *flash); + +#ifdef CONFIG_V4L2_FLASH_LED_CLASS +/** + * led_get_v4l2_flash_ops - get ops for controlling LED Flash Class + device with use of V4L2 Flash controls + * Returns: v4l2_flash_ops + */ +const struct v4l2_flash_ops *led_get_v4l2_flash_ops(void); +#else +#define led_get_v4l2_flash_ops() (0) +#endif + +#endif /* __LINUX_FLASH_LEDS_H_INCLUDED */ diff --git a/include/linux/led-flash-gpio-mux.h b/include/linux/led-flash-gpio-mux.h new file mode 100644 index 0000000..c56d38f --- /dev/null +++ b/include/linux/led-flash-gpio-mux.h @@ -0,0 +1,68 @@ +/* + * LED Flash Class gpio mux + * + * Copyright (C) 2014 Samsung Electronics Co., Ltd + * Author: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation." + */ + +#ifndef _LED_FLASH_GPIO_MUX_H +#define _LED_FLASH_GPIO_MUX_H + +struct device_node; + +struct list_head; + +/** + * struct led_flash_gpio_mux_selector - element of gpio mux selectors list + * @list: links mux selectors + * @gpio: mux selector gpio + */ +struct led_flash_gpio_mux_selector { + struct list_head list; + int gpio; +}; + +/** + * struct led_flash_gpio_mux - gpio mux + * @selectors: mux selectors + */ +struct led_flash_gpio_mux { + struct list_head selectors; +}; + +/** + * led_flash_gpio_mux_create - create gpio mux + * @new_mux: created mux + * @mux_node: device tree node with gpio definitions + * + * Create V4L2 subdev wrapping given LED subsystem device. + * + * Returns: 0 on success or negative error value on failure + */ +int led_flash_gpio_mux_create(struct led_flash_gpio_mux **new_mux, + struct device_node *mux_node); + +/** + * led_flash_gpio_mux_release - release gpio mux + * @gpio_mux: mux to be released + * + * Create V4L2 subdev wrapping given LED subsystem device. + */ +void led_flash_gpio_mux_release(void *gpio_mux); + +/** + * led_flash_gpio_mux_select_line - select mux line + * @line_id: id of the line to be selected + * @mux: mux to be set + * + * Create V4L2 subdev wrapping given LED subsystem device. + * + * Returns: 0 on success or negative error value on failure + */ +int led_flash_gpio_mux_select_line(u32 line_id, void *mux); + +#endif /* _LED_FLASH_GPIO_MUX_H */ diff --git a/include/linux/led-flash-manager.h b/include/linux/led-flash-manager.h new file mode 100644 index 0000000..174eedb --- /dev/null +++ b/include/linux/led-flash-manager.h @@ -0,0 +1,121 @@ +/* + * LED Flash Manager for maintaining LED Flash Class devices + * along with their corresponding muxes that faciliate dynamic + * reconfiguration of the strobe signal source. + * + * Copyright (C) 2014 Samsung Electronics Co., Ltd + * Author: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation." + */ + +#ifndef _LED_FLASH_MANAGER_H +#define _LED_FLASH_MANAGER_H + +#include <linux/types.h> + +struct list_head; + +struct led_flash_mux_ops { + /* select mux line */ + int (*select_line)(u32 line_id, void *mux); + /* + * release private mux data - it is intended for gpio muxes + * only and mustn't be initialized by asynchronous muxes. + */ + void (*release_private_data)(void *mux); +}; + +/** + * struct led_flash_mux_ref - flash mux reference + * @list: links flashes pointing to a mux + * @flash: flash holding a mux reference + */ +struct led_flash_mux_ref { + struct list_head list; + struct led_classdev_flash *flash; +}; + +/** + * struct led_flash_mux - flash mux used for routing strobe signal + * @list: list of muxes declared by registered flashes + * @node: mux Device Tree node + * @private_data: mux internal data + * @ops: ops facilitating mux state manipulation + * @refs: list of flashes using the mux + * @num_refs: number of flashes using the mux + * @owner: module owning an async mux driver + */ +struct led_flash_mux { + struct list_head list; + struct device_node *node; + void *private_data; + struct led_flash_mux_ops *ops; + struct list_head refs; + int num_refs; + struct module *owner; +}; + +/** + * led_flash_manager_setup_strobe - setup flash strobe + * @flash: the LED Flash Class device to strobe + * @external: true - setup external strobe, + * false - setup software strobe + * + * Configure muxes to route relevant strobe signals to the + * flash led device and strobe the flash if software strobe + * is to be activated. If the flash device depends on shared + * muxes the caller is blocked for the flash_timeout period. + * + * Returns: 0 on success or negative error value on failure. + */ +int led_flash_manager_setup_strobe(struct led_classdev_flash *flash, + bool external); + +/** + * led_flash_manager_bind_async_mux - bind asynchronous mulitplexer + * @async_mux: mux registration data + * + * Notify the flash manager that an asychronous mux has been probed. + * + * Returns: 0 on success or negative error value on failure. + */ +int led_flash_manager_bind_async_mux(struct led_flash_mux *async_mux); + +/** + * led_flash_manager_unbind_async_mux - unbind asynchronous mulitplexer + * @mux_node: device node of the mux to be unbound + * + * Notify the flash manager that an asychronous mux has been removed. + * + * Returns: 0 on success or negative error value on failure. + */ +int led_flash_manager_unbind_async_mux(struct device_node *mux_node); + +/** + * led_flash_manager_register_flash - register LED Flash Class device + in the flash manager + * @flash: the LED Flash Class device to be registered + * @node: Device Tree node - it is expected to contain information + * about strobe signal topology + * + * Register LED Flash Class device and retrieve information + * about related strobe signals topology. + * + * Returns: 0 on success or negative error value on failure. + */ +int led_flash_manager_register_flash(struct led_classdev_flash *flash, + struct device_node *node); + +/** + * led_flash_manager_unregister_flash - unregister LED Flash Class device + * from the flash manager + * @flash: the LED Flash Class device to be unregistered + * + * Unregister LED Flash Class device from the flash manager. + */ +void led_flash_manager_unregister_flash(struct led_classdev_flash *flash); + +#endif /* _LED_FLASH_MANAGER_H */ diff --git a/include/linux/leds.h b/include/linux/leds.h index 9bea9e6..1f12d36 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -45,6 +45,9 @@ struct led_classdev { #define LED_BLINK_INVERT (1 << 19) #define LED_SYSFS_LOCK (1 << 20) #define LED_DEV_CAP_TORCH (1 << 21) +#define LED_DEV_CAP_FLASH (1 << 22) +#define LED_DEV_CAP_INDICATOR (1 << 23) +#define LED_DEV_CAP_FL_MANAGER (1 << 24) /* Set LED brightness level */ /* Must not sleep, use a workqueue if needed */ @@ -83,6 +86,7 @@ struct led_classdev { unsigned long blink_delay_on, blink_delay_off; struct timer_list blink_timer; int blink_brightness; + void (*flash_resume)(struct led_classdev *led_cdev); struct work_struct set_brightness_work; int delayed_set_value; diff --git a/include/linux/of_led_flash_manager.h b/include/linux/of_led_flash_manager.h new file mode 100644 index 0000000..d27cb46 --- /dev/null +++ b/include/linux/of_led_flash_manager.h @@ -0,0 +1,80 @@ +/* + * LED flash manager of helpers. + * + * Copyright (C) 2014 Samsung Electronics Co., Ltd + * Author: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation." + */ + +#ifndef _OF_LED_FLASH_MANAGER_H +#define _OF_LED_FLASH_MANAGER_H + +#include <linux/sysfs.h> +#include <linux/device.h> + +struct led_classdev_flash; +struct device_node; +struct list_head; + +#define MAX_ATTR_NAME 18 /* allows for strobe providers ids up to 999 */ + +/** + * struct led_flash_strobe_gate - strobe signal gate + * @list: links gates + * @mux_node: gate's parent mux + * @line_id: id of a mux line that the gate represents + */ +struct led_flash_strobe_gate { + struct list_head list; + struct device_node *mux_node; + u32 line_id; +}; + +/** + * struct led_flash_strobe_provider - external strobe signal provider that + may be associated with the flash device + * @list: links strobe providers + * @strobe_gates: list of gates that route strobe signal + from the strobe provider to the flash device + * @node: device node of the strobe provider device + */ +struct led_flash_strobe_provider { + struct list_head list; + struct list_head strobe_gates; + const char *name; + struct device_attribute attr; + char attr_name[MAX_ATTR_NAME]; + bool attr_registered; +}; + +/** + * of_led_flash_manager_parse_dt - parse flash manager data of + * a LED Flash Class device DT node + * + * @flash: the LED Flash Class device to store the parsed data in + * @node: device node to parse + * + * Parse the multiplexers' settings that need to be applied for + * opening a route to all the flash strobe signals available for + * the device. + * + * Returns: 0 on success or negative error value on failure + */ +int of_led_flash_manager_parse_dt(struct led_classdev_flash *flash, + struct device_node *node); + + +/** + * of_led_flash_manager_release_dt_data - release parsed DT data + * + * @flash: the LED Flash Class device to release data from + * + * Release data structures containing information about strobe + * source routes available for the device. + */ +void of_led_flash_manager_release_dt_data(struct led_classdev_flash *flash); + +#endif /* _OF_LED_FLASH_MANAGER_H */ -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html