Hi Jacek,
Jacek Anaszewski wrote:
> This patch adds helper functions for registering/unregistering
> LED class flash devices as V4L2 subdevs. The functions should
> be called from the LED subsystem device driver. In case the
> support for V4L2 Flash sub-devices is disabled in the kernel
> config the functions' empty versions will be used.
>
> Signed-off-by: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx>
> Acked-by: Kyungmin Park <kyungmin.park@xxxxxxxxxxx>
> Cc: Sakari Ailus <sakari.ailus@xxxxxx>
> Cc: Hans Verkuil <hans.verkuil@xxxxxxxxx>
> ---
> drivers/media/v4l2-core/Kconfig | 11 +
> drivers/media/v4l2-core/Makefile | 2 +
> drivers/media/v4l2-core/v4l2-flash.c | 580 ++++++++++++++++++++++++++++++++++
> include/media/v4l2-flash.h | 137 ++++++++
> 4 files changed, 730 insertions(+)
> create mode 100644 drivers/media/v4l2-core/v4l2-flash.c
> create mode 100644 include/media/v4l2-flash.h
>
> diff --git a/drivers/media/v4l2-core/Kconfig b/drivers/media/v4l2-core/Kconfig
> index 9ca0f8d..3ae3f0f 100644
> --- a/drivers/media/v4l2-core/Kconfig
> +++ b/drivers/media/v4l2-core/Kconfig
> @@ -35,6 +35,17 @@ config V4L2_MEM2MEM_DEV
> tristate
> depends on VIDEOBUF2_CORE
>
> +# Used by LED subsystem flash drivers
> +config V4L2_FLASH_LED_CLASS
> + bool "Enable support for Flash sub-devices"
> + depends on VIDEO_V4L2_SUBDEV_API
> + depends on LEDS_CLASS_FLASH
> + ---help---
> + Say Y here to enable support for Flash sub-devices, which allow
> + to control LED class devices with use of V4L2 Flash controls.
> +
> + When in doubt, say N.
> +
> # Used by drivers that need Videobuf modules
> config VIDEOBUF_GEN
> tristate
> diff --git a/drivers/media/v4l2-core/Makefile b/drivers/media/v4l2-core/Makefile
> index 63d29f2..44e858c 100644
> --- a/drivers/media/v4l2-core/Makefile
> +++ b/drivers/media/v4l2-core/Makefile
> @@ -22,6 +22,8 @@ obj-$(CONFIG_VIDEO_TUNER) += tuner.o
>
> obj-$(CONFIG_V4L2_MEM2MEM_DEV) += v4l2-mem2mem.o
>
> +obj-$(CONFIG_V4L2_FLASH_LED_CLASS) += v4l2-flash.o
> +
> obj-$(CONFIG_VIDEOBUF_GEN) += videobuf-core.o
> obj-$(CONFIG_VIDEOBUF_DMA_SG) += videobuf-dma-sg.o
> obj-$(CONFIG_VIDEOBUF_DMA_CONTIG) += videobuf-dma-contig.o
> diff --git a/drivers/media/v4l2-core/v4l2-flash.c b/drivers/media/v4l2-core/v4l2-flash.c
> new file mode 100644
> index 0000000..21080c6
> --- /dev/null
> +++ b/drivers/media/v4l2-core/v4l2-flash.c
> @@ -0,0 +1,580 @@
> +/*
> + * V4L2 Flash LED sub-device registration 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/led-class-flash.h>
> +#include <linux/mutex.h>
> +#include <linux/of_led_flash_manager.h>
> +#include <linux/slab.h>
> +#include <media/v4l2-flash.h>
> +
> +#define call_flash_op(v4l2_flash, op, args...) \
> + (v4l2_flash->ops->op ? \
> + v4l2_flash->ops->op(args) : \
> + -EINVAL)
> +
> +static struct v4l2_device *v4l2_dev;
> +static int registered_flashes;
> +
> +static inline enum led_brightness v4l2_flash_intensity_to_led_brightness(
> + struct v4l2_ctrl_config *config,
> + s32 intensity)
> +{
> + return ((intensity - config->min) / config->step) + 1;
> +}
> +
> +static inline s32 v4l2_flash_led_brightness_to_intensity(
> + struct v4l2_ctrl_config *config,
> + enum led_brightness brightness)
> +{
> + return ((brightness - 1) * config->step) + config->min;
> +}
> +
> +static int v4l2_flash_g_volatile_ctrl(struct v4l2_ctrl *c)
> +
> +{
> + struct v4l2_flash *v4l2_flash = v4l2_ctrl_to_v4l2_flash(c);
> + struct led_classdev_flash *flash = v4l2_flash->flash;
> + struct led_classdev *led_cdev = &flash->led_cdev;
> + struct v4l2_flash_ctrl_config *config = &v4l2_flash->config;
> + struct v4l2_flash_ctrl *ctrl = &v4l2_flash->ctrl;
> + bool is_strobing;
> + int ret;
> +
> + switch (c->id) {
> + case V4L2_CID_FLASH_TORCH_INTENSITY:
> + /*
> + * Update torch brightness only if in TORCH_MODE,
> + * as otherwise brightness_update op returns 0,
> + * which would spuriously inform user space that
> + * V4L2_CID_FLASH_TORCH_INTENSITY control value
> + * has changed.
> + */
> + if (ctrl->led_mode->val == V4L2_FLASH_LED_MODE_TORCH) {
> + ret = call_flash_op(v4l2_flash, torch_brightness_update,
> + led_cdev);
> + if (ret < 0)
> + return ret;
> + ctrl->torch_intensity->val =
> + v4l2_flash_led_brightness_to_intensity(
> + &config->torch_intensity,
> + led_cdev->brightness);
> + }
> + return 0;
> + case V4L2_CID_FLASH_INTENSITY:
> + ret = call_flash_op(v4l2_flash, flash_brightness_update,
> + flash);
> + if (ret < 0)
> + return ret;
> + /* no conversion is needed */
> + c->val = flash->brightness.val;
> + return 0;
> + case V4L2_CID_FLASH_INDICATOR_INTENSITY:
> + ret = call_flash_op(v4l2_flash, indicator_brightness_update,
> + flash);
> + if (ret < 0)
> + return ret;
> + /* no conversion is needed */
> + c->val = flash->indicator_brightness->val;
> + return 0;
> + case V4L2_CID_FLASH_STROBE_STATUS:
> + ret = call_flash_op(v4l2_flash, strobe_get, flash,
> + &is_strobing);
> + if (ret < 0)
> + return ret;
> + c->val = is_strobing;
> + return 0;
> + case V4L2_CID_FLASH_FAULT:
> + /* led faults map directly to V4L2 flash faults */
> + ret = call_flash_op(v4l2_flash, fault_get, flash, &c->val);
> + return ret;
> + case V4L2_CID_FLASH_STROBE_SOURCE:
> + c->val = flash->external_strobe;
> + return 0;
> + case V4L2_CID_FLASH_STROBE_PROVIDER:
> + c->val = flash->strobe_provider_id;
> + return 0;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int v4l2_flash_s_ctrl(struct v4l2_ctrl *c)
> +{
> + struct v4l2_flash *v4l2_flash = v4l2_ctrl_to_v4l2_flash(c);
> + struct led_classdev_flash *flash = v4l2_flash->flash;
> + struct v4l2_flash_ctrl *ctrl = &v4l2_flash->ctrl;
> + struct v4l2_flash_ctrl_config *config = &v4l2_flash->config;
> + enum led_brightness torch_brightness;
> + bool external_strobe;
> + int ret;
> +
> + switch (c->id) {
> + case V4L2_CID_FLASH_LED_MODE:
> + switch (c->val) {
> + case V4L2_FLASH_LED_MODE_NONE:
> + call_flash_op(v4l2_flash, torch_brightness_set,
> + &flash->led_cdev, 0);
> + return call_flash_op(v4l2_flash, strobe_set, flash,
> + false);
> + case V4L2_FLASH_LED_MODE_FLASH:
> + /* Turn off torch LED */
> + call_flash_op(v4l2_flash, torch_brightness_set,
> + &flash->led_cdev, 0);
> + external_strobe = (ctrl->source->val ==
> + V4L2_FLASH_STROBE_SOURCE_EXTERNAL);
> + return call_flash_op(v4l2_flash, external_strobe_set,
> + flash, external_strobe);
> + case V4L2_FLASH_LED_MODE_TORCH:
> + /* Stop flash strobing */
> + ret = call_flash_op(v4l2_flash, strobe_set, flash,
> + false);
> + if (ret)
> + return ret;
> +
> + torch_brightness =
> + v4l2_flash_intensity_to_led_brightness(
> + &config->torch_intensity,
> + ctrl->torch_intensity->val);
> + call_flash_op(v4l2_flash, torch_brightness_set,
> + &flash->led_cdev, torch_brightness);
> + return ret;
> + }
> + break;
> + case V4L2_CID_FLASH_STROBE_SOURCE:
> + external_strobe = (c->val == V4L2_FLASH_STROBE_SOURCE_EXTERNAL);
Is the external_strobe argument match exactly to the strobe source
control? You seem to assume that in g_volatile_ctrl() above. I think
having it the either way is fine but not both. :-)
> + return call_flash_op(v4l2_flash, external_strobe_set, flash,
> + external_strobe);
> + case V4L2_CID_FLASH_STROBE:
> + if (ctrl->led_mode->val != V4L2_FLASH_LED_MODE_FLASH ||
> + ctrl->source->val != V4L2_FLASH_STROBE_SOURCE_SOFTWARE)
> + return -EINVAL;
> + return call_flash_op(v4l2_flash, strobe_set, flash, true);
> + case V4L2_CID_FLASH_STROBE_STOP:
Should we check the flash mode here? I guess so. How about strobe source
as well?
> + return call_flash_op(v4l2_flash, strobe_set, flash, false);
> + case V4L2_CID_FLASH_TIMEOUT:
> + return call_flash_op(v4l2_flash, timeout_set, flash, c->val);
> + case V4L2_CID_FLASH_INTENSITY:
> + /* no conversion is needed */
> + return call_flash_op(v4l2_flash, flash_brightness_set, flash,
> + c->val);
> + case V4L2_CID_FLASH_INDICATOR_INTENSITY:
> + /* no conversion is needed */
> + return call_flash_op(v4l2_flash, indicator_brightness_set,
> + flash, c->val);
> + case V4L2_CID_FLASH_TORCH_INTENSITY:
> + /*
> + * If not in MODE_TORCH don't call led-class brightness_set
> + * op, as it would result in turning the torch led on.
> + * Instead the value is cached only and will be written
> + * to the device upon transition to MODE_TORCH.
> + */
> + if (ctrl->led_mode->val == V4L2_FLASH_LED_MODE_TORCH) {
> + torch_brightness =
> + v4l2_flash_intensity_to_led_brightness(
> + &config->torch_intensity,
> + ctrl->torch_intensity->val);
> + call_flash_op(v4l2_flash, torch_brightness_set,
> + &flash->led_cdev, torch_brightness);
> + }
> + return 0;
> + case V4L2_CID_FLASH_STROBE_PROVIDER:
> + flash->strobe_provider_id = c->val;
> + return 0;
> + }
> +
> + return -EINVAL;
> +}
> +
> +static const struct v4l2_ctrl_ops v4l2_flash_ctrl_ops = {
> + .g_volatile_ctrl = v4l2_flash_g_volatile_ctrl,
> + .s_ctrl = v4l2_flash_s_ctrl,
> +};
> +
> +static int v4l2_flash_init_strobe_providers_menu(struct v4l2_flash *v4l2_flash)
> +{
> + struct led_classdev_flash *flash = v4l2_flash->flash;
> + struct led_flash_strobe_provider *provider;
> + struct v4l2_ctrl *ctrl;
> + int i = 0;
> +
> + v4l2_flash->strobe_providers_menu =
> + kzalloc(sizeof(char *) * (flash->num_strobe_providers),
> + GFP_KERNEL);
> + if (!v4l2_flash->strobe_providers_menu)
> + return -ENOMEM;
> +
> + list_for_each_entry(provider, &flash->strobe_providers, list)
> + v4l2_flash->strobe_providers_menu[i++] =
> + (char *) provider->name;
> +
> + ctrl = v4l2_ctrl_new_std_menu_items(
> + &v4l2_flash->hdl, &v4l2_flash_ctrl_ops,
> + V4L2_CID_FLASH_STROBE_PROVIDER,
> + flash->num_strobe_providers - 1,
> + 0, 0,
> + (const char * const *) v4l2_flash->strobe_providers_menu);
> +
> + if (ctrl)
> + ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;
> +
> + return 0;
> +}
> +
> +static int v4l2_flash_init_controls(struct v4l2_flash *v4l2_flash)
> +
> +{
> + struct led_classdev_flash *flash = v4l2_flash->flash;
> + const struct led_flash_ops *flash_ops = flash->ops;
> + struct led_classdev *led_cdev = &flash->led_cdev;
> + struct v4l2_flash_ctrl_config *config = &v4l2_flash->config;
> + struct v4l2_ctrl *ctrl;
> + struct v4l2_ctrl_config *ctrl_cfg;
> + bool has_flash = led_cdev->flags & LED_DEV_CAP_FLASH;
> + bool has_indicator = led_cdev->flags & LED_DEV_CAP_INDICATOR;
> + bool has_strobe_providers = (flash->num_strobe_providers > 1);
> + unsigned int mask;
> + int ret, max, num_ctrls;
> +
> + num_ctrls = has_flash ? 5 : 2;
> + if (has_flash) {
> + if (flash_ops->flash_brightness_set)
> + ++num_ctrls;
> + if (flash_ops->timeout_set)
> + ++num_ctrls;
> + if (flash_ops->strobe_get)
> + ++num_ctrls;
> + if (has_indicator)
> + ++num_ctrls;
> + if (config->flash_faults)
> + ++num_ctrls;
> + if (has_strobe_providers)
> + ++num_ctrls;
> + }
> +
> + v4l2_ctrl_handler_init(&v4l2_flash->hdl, num_ctrls);
> +
> + mask = 1 << V4L2_FLASH_LED_MODE_NONE |
> + 1 << V4L2_FLASH_LED_MODE_TORCH;
> + if (flash)
> + mask |= 1 << V4L2_FLASH_LED_MODE_FLASH;
> +
> + /* Configure FLASH_LED_MODE ctrl */
> + v4l2_flash->ctrl.led_mode = v4l2_ctrl_new_std_menu(
> + &v4l2_flash->hdl,
> + &v4l2_flash_ctrl_ops, V4L2_CID_FLASH_LED_MODE,
> + V4L2_FLASH_LED_MODE_TORCH, ~mask,
> + V4L2_FLASH_LED_MODE_NONE);
> +
> + /* Configure TORCH_INTENSITY ctrl */
> + ctrl_cfg = &config->torch_intensity;
> + ctrl = v4l2_ctrl_new_std(&v4l2_flash->hdl, &v4l2_flash_ctrl_ops,
> + V4L2_CID_FLASH_TORCH_INTENSITY,
> + ctrl_cfg->min, ctrl_cfg->max,
> + ctrl_cfg->step, ctrl_cfg->def);
> + if (ctrl)
> + ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;
> + v4l2_flash->ctrl.torch_intensity = ctrl;
> +
> + if (has_flash) {
> + /* Configure FLASH_STROBE_SOURCE ctrl */
> + mask = 1 << V4L2_FLASH_STROBE_SOURCE_SOFTWARE;
> +
> + if (flash->has_external_strobe) {
> + mask |= 1 << V4L2_FLASH_STROBE_SOURCE_EXTERNAL;
> + max = V4L2_FLASH_STROBE_SOURCE_EXTERNAL;
> + } else {
> + max = V4L2_FLASH_STROBE_SOURCE_SOFTWARE;
> + }
> +
> + v4l2_flash->ctrl.source = v4l2_ctrl_new_std_menu(
> + &v4l2_flash->hdl,
> + &v4l2_flash_ctrl_ops,
> + V4L2_CID_FLASH_STROBE_SOURCE,
> + max,
> + ~mask,
> + V4L2_FLASH_STROBE_SOURCE_SOFTWARE);
> + if (v4l2_flash->ctrl.source)
> + v4l2_flash->ctrl.source->flags |=
> + V4L2_CTRL_FLAG_VOLATILE;
> +
> + /* Configure FLASH_STROBE ctrl */
> + ctrl = v4l2_ctrl_new_std(&v4l2_flash->hdl, &v4l2_flash_ctrl_ops,
> + V4L2_CID_FLASH_STROBE, 0, 1, 1, 0);
> +
> + /* Configure FLASH_STROBE_STOP ctrl */
> + ctrl = v4l2_ctrl_new_std(&v4l2_flash->hdl, &v4l2_flash_ctrl_ops,
> + V4L2_CID_FLASH_STROBE_STOP,
> + 0, 1, 1, 0);
> +
> + /* Configure FLASH_STROBE_STATUS ctrl */
> + ctrl = v4l2_ctrl_new_std(&v4l2_flash->hdl, &v4l2_flash_ctrl_ops,
> + V4L2_CID_FLASH_STROBE_STATUS,
> + 0, 1, 1, 1);
I think you only should implement the strobe status control if you
really can know it, i.e. have strobe_get().
> + if (flash_ops->strobe_get)
> + if (ctrl)
> + ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE |
> + V4L2_CTRL_FLAG_READ_ONLY;
> +
> + if (flash_ops->timeout_set) {
> + /* Configure FLASH_TIMEOUT ctrl */
> + ctrl_cfg = &config->flash_timeout;
> + ctrl = v4l2_ctrl_new_std(
> + &v4l2_flash->hdl, &v4l2_flash_ctrl_ops,
> + V4L2_CID_FLASH_TIMEOUT, ctrl_cfg->min,
> + ctrl_cfg->max, ctrl_cfg->step,
> + ctrl_cfg->def);
> + if (ctrl)
> + ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;
> + }
> +
> + if (flash_ops->flash_brightness_set) {
> + /* Configure FLASH_INTENSITY ctrl */
> + ctrl_cfg = &config->flash_intensity;
> + ctrl = v4l2_ctrl_new_std(
> + &v4l2_flash->hdl,
> + &v4l2_flash_ctrl_ops,
> + V4L2_CID_FLASH_INTENSITY,
> + ctrl_cfg->min, ctrl_cfg->max,
> + ctrl_cfg->step, ctrl_cfg->def);
> + if (ctrl)
> + ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;
> + }
> +
> + if (config->flash_faults) {
> + /* Configure FLASH_FAULT ctrl */
> + ctrl = v4l2_ctrl_new_std(&v4l2_flash->hdl,
> + &v4l2_flash_ctrl_ops,
> + V4L2_CID_FLASH_FAULT, 0,
> + config->flash_faults,
> + 0, 0);
> + if (ctrl)
> + ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE |
> + V4L2_CTRL_FLAG_READ_ONLY;
> + }
> + if (has_indicator) {
> + /* Configure FLASH_INDICATOR_INTENSITY ctrl */
> + ctrl_cfg = &config->indicator_intensity;
> + ctrl = v4l2_ctrl_new_std(
> + &v4l2_flash->hdl, &v4l2_flash_ctrl_ops,
> + V4L2_CID_FLASH_INDICATOR_INTENSITY,
> + ctrl_cfg->min, ctrl_cfg->max,
> + ctrl_cfg->step, ctrl_cfg->def);
> + if (ctrl)
> + ctrl->flags |= V4L2_CTRL_FLAG_VOLATILE;
> + }
Could you implement the above in a loop? You're essentially repeating
the same but with different parameters.
> + if (has_strobe_providers) {
> + /* Configure V4L2_CID_FLASH_STROBE_PROVIDERS ctrl */
> + ret = v4l2_flash_init_strobe_providers_menu(v4l2_flash);
> + if (ret < 0)
> + goto error_free_handler;
> + }
> + }
> +
> + if (v4l2_flash->hdl.error) {
> + ret = v4l2_flash->hdl.error;
> + goto error_free_handler;
> + }
> +
> + ret = v4l2_ctrl_handler_setup(&v4l2_flash->hdl);
> + if (ret < 0)
> + goto error_free_handler;
> +
> + v4l2_flash->sd.ctrl_handler = &v4l2_flash->hdl;
> +
> + return 0;
> +
> +error_free_handler:
> + v4l2_ctrl_handler_free(&v4l2_flash->hdl);
> + return ret;
> +}
> +
> +/*
> + * V4L2 subdev internal operations
> + */
> +
> +static int v4l2_flash_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> +{
> + struct v4l2_flash *v4l2_flash = v4l2_subdev_to_v4l2_flash(sd);
> + struct led_classdev_flash *flash = v4l2_flash->flash;
> + struct led_classdev *led_cdev = &flash->led_cdev;
> +
> + mutex_lock(&led_cdev->led_lock);
> + call_flash_op(v4l2_flash, sysfs_lock, led_cdev);
What if you have the device open through multiple file handles? I
believe v4l2_subdev_fh_is_singular(&fh->vfh) would prove helpful here.
> + mutex_unlock(&led_cdev->led_lock);
> +
> + return 0;
> +}
> +
> +static int v4l2_flash_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> +{
> + struct v4l2_flash *v4l2_flash = v4l2_subdev_to_v4l2_flash(sd);
> + struct led_classdev_flash *flash = v4l2_flash->flash;
> + struct led_classdev *led_cdev = &flash->led_cdev;
> +
> + mutex_lock(&led_cdev->led_lock);
> + call_flash_op(v4l2_flash, sysfs_unlock, led_cdev);
> + mutex_unlock(&led_cdev->led_lock);
> +
> + return 0;
> +}
> +
> +int v4l2_flash_register(struct v4l2_flash *v4l2_flash)
Do you expect to call this from elsewhere than this file?
> +{
> + struct led_classdev_flash *flash = v4l2_flash->flash;
> + struct led_classdev *led_cdev = &flash->led_cdev;
> + int ret;
> +
> + if (!v4l2_dev) {
> + v4l2_dev = kzalloc(sizeof(*v4l2_dev), GFP_KERNEL);
> + if (!v4l2_dev)
> + return -ENOMEM;
> +
> + strlcpy(v4l2_dev->name, "v4l2-flash-manager",
> + sizeof(v4l2_dev->name));
> + ret = v4l2_device_register(NULL, v4l2_dev);
> + if (ret < 0) {
> + dev_err(led_cdev->dev->parent,
> + "Failed to register v4l2_device: %d\n", ret);
> + goto err_v4l2_device_register;
> + }
> + }
> +
> + ret = v4l2_device_register_subdev(v4l2_dev, &v4l2_flash->sd);
> + if (ret < 0) {
> + dev_err(led_cdev->dev->parent,
> + "Failed to register v4l2_subdev: %d\n", ret);
> + goto err_v4l2_device_register;
> + }
> +
> + ret = v4l2_device_register_subdev_node(&v4l2_flash->sd, v4l2_dev);
> + if (ret < 0) {
> + dev_err(led_cdev->dev->parent,
> + "Failed to register v4l2_subdev node: %d\n", ret);
> + goto err_register_subdev_node;
> + }
This way you can create a V4L2 sub-device node. However, flash devices
are seldom alone in the system. They are physically close to a sensor,
and this connection is shown in the Media controller interface. This
means that the flash sub-device (entity) should be part of the Media
device created by the driver in control of it. This can be achieved by
the master driver creating the sub-device. You should register an async
sub-device here.
This results in the sub-device not being registered if there's no such
master driver, but I wouldn't expect that to be an issue since the V4L2
flash API is mostly relevant in such cases.
> + ++registered_flashes;
> +
> + return 0;
> +
> +err_register_subdev_node:
> + v4l2_device_unregister_subdev(&v4l2_flash->sd);
> +err_v4l2_device_register:
> + kfree(v4l2_flash->strobe_providers_menu);
> + if (v4l2_dev && registered_flashes == 0) {
> + v4l2_device_unregister(v4l2_dev);
> + kfree(v4l2_dev);
> + v4l2_dev = NULL;
> + }
> +
> + return ret;
> +}
> +
> +static void v4l2_flash_unregister(struct v4l2_flash *v4l2_flash)
> +{
> + if (registered_flashes == 0)
> + return;
> +
> + v4l2_device_unregister_subdev(&v4l2_flash->sd);
> +
> + --registered_flashes;
> +
> + if (registered_flashes == 0) {
> + v4l2_device_unregister(v4l2_dev);
> + kfree(v4l2_dev);
> + v4l2_dev = NULL;
> + }
> +}
> +
> +static const struct v4l2_subdev_internal_ops v4l2_flash_subdev_internal_ops = {
> + .open = v4l2_flash_open,
> + .close = v4l2_flash_close,
> +};
> +
> +static const struct v4l2_subdev_core_ops v4l2_flash_core_ops = {
> + .queryctrl = v4l2_subdev_queryctrl,
> + .querymenu = v4l2_subdev_querymenu,
> +};
> +
> +static const struct v4l2_subdev_ops v4l2_flash_subdev_ops = {
> + .core = &v4l2_flash_core_ops,
> +};
> +
> +int v4l2_flash_init(struct led_classdev_flash *flash,
> + struct v4l2_flash_ctrl_config *config,
> + const struct v4l2_flash_ops *flash_ops,
> + struct v4l2_flash **out_flash)
> +{
> + struct v4l2_flash *v4l2_flash;
> + struct led_classdev *led_cdev = &flash->led_cdev;
> + struct v4l2_subdev *sd;
> + int ret;
> +
> + if (!flash || !config || !out_flash)
> + return -EINVAL;
> +
> + v4l2_flash = kzalloc(sizeof(*v4l2_flash), GFP_KERNEL);
> + if (!v4l2_flash)
> + return -ENOMEM;
> +
> + sd = &v4l2_flash->sd;
> + v4l2_flash->flash = flash;
> + v4l2_flash->ops = flash_ops;
> + sd->dev = led_cdev->dev->parent;
> + v4l2_subdev_init(sd, &v4l2_flash_subdev_ops);
> + sd->internal_ops = &v4l2_flash_subdev_internal_ops;
> + sd->flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> + snprintf(sd->name, sizeof(sd->name), led_cdev->name);
> +
> + v4l2_flash->config = *config;
> + ret = v4l2_flash_init_controls(v4l2_flash);
> + if (ret < 0)
> + goto err_init_controls;
> +
> + ret = media_entity_init(&sd->entity, 0, NULL, 0);
> + if (ret < 0)
> + goto err_init_entity;
> +
> + sd->entity.type = MEDIA_ENT_T_V4L2_SUBDEV_FLASH;
> +
> + ret = v4l2_flash_register(v4l2_flash);
> + if (ret < 0)
> + goto err_init_entity;
> +
> + *out_flash = v4l2_flash;
How about returning the pointer instead?
> + return 0;
> +
> +err_init_entity:
> + media_entity_cleanup(&sd->entity);
> +err_init_controls:
> + v4l2_ctrl_handler_free(sd->ctrl_handler);
> + kfree(v4l2_flash);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(v4l2_flash_init);
> +
> +void v4l2_flash_release(struct v4l2_flash *v4l2_flash)
> +{
> + if (!v4l2_flash)
> + return;
> +
> + v4l2_flash_unregister(v4l2_flash);
> + v4l2_ctrl_handler_free(v4l2_flash->sd.ctrl_handler);
> + media_entity_cleanup(&v4l2_flash->sd.entity);
> + kfree(v4l2_flash->strobe_providers_menu);
> + kfree(v4l2_flash);
> +}
> +EXPORT_SYMBOL_GPL(v4l2_flash_release);
> diff --git a/include/media/v4l2-flash.h b/include/media/v4l2-flash.h
> new file mode 100644
> index 0000000..effa46b
> --- /dev/null
> +++ b/include/media/v4l2-flash.h
> @@ -0,0 +1,137 @@
> +/*
> + * V4L2 Flash LED sub-device registration 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 _V4L2_FLASH_H
> +#define _V4L2_FLASH_H
> +
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-dev.h>
> +#include <media/v4l2-event.h>
> +#include <media/v4l2-ioctl.h>
> +
> +struct led_classdev_flash;
> +struct led_classdev;
> +enum led_brightness;
> +
> +struct v4l2_flash_ops {
> + int (*torch_brightness_set)(struct led_classdev *led_cdev,
> + enum led_brightness brightness);
> + int (*torch_brightness_update)(struct led_classdev *led_cdev);
> + int (*flash_brightness_set)(struct led_classdev_flash *flash,
> + u32 brightness);
> + int (*flash_brightness_update)(struct led_classdev_flash *flash);
> + int (*strobe_set)(struct led_classdev_flash *flash, bool state);
> + int (*strobe_get)(struct led_classdev_flash *flash, bool *state);
> + int (*timeout_set)(struct led_classdev_flash *flash, u32 timeout);
> + int (*indicator_brightness_set)(struct led_classdev_flash *flash,
> + u32 brightness);
> + int (*indicator_brightness_update)(struct led_classdev_flash *flash);
> + int (*external_strobe_set)(struct led_classdev_flash *flash,
> + bool enable);
> + int (*fault_get)(struct led_classdev_flash *flash, u32 *fault);
> + void (*sysfs_lock)(struct led_classdev *led_cdev);
> + void (*sysfs_unlock)(struct led_classdev *led_cdev);
These functions are not driver specific and there's going to be just one
implementation (I suppose). Could you refresh my memory regarding why
the LED framework functions aren't called directly?
> +};
> +
> +/**
> + * struct v4l2_flash_ctrl - controls that define the sub-dev's state
> + * @source: V4L2_CID_FLASH_STROBE_SOURCE control
> + * @led_mode: V4L2_CID_FLASH_LED_MODE control
> + * @torch_intensity: V4L2_CID_FLASH_TORCH_INTENSITY control
> + */
> +struct v4l2_flash_ctrl {
> + struct v4l2_ctrl *source;
> + struct v4l2_ctrl *led_mode;
> + struct v4l2_ctrl *torch_intensity;
> +};
> +
> +/**
> + * struct v4l2_flash_ctrl_config - V4L2 Flash controls initialization data
> + * @torch_intensity: V4L2_CID_FLASH_TORCH_INTENSITY constraints
> + * @flash_intensity: V4L2_CID_FLASH_INTENSITY constraints
> + * @indicator_intensity: V4L2_CID_FLASH_INDICATOR_INTENSITY constraints
> + * @flash_timeout: V4L2_CID_FLASH_TIMEOUT constraints
> + * @flash_fault: possible flash faults
> + */
> +struct v4l2_flash_ctrl_config {
> + struct v4l2_ctrl_config torch_intensity;
> + struct v4l2_ctrl_config flash_intensity;
> + struct v4l2_ctrl_config indicator_intensity;
> + struct v4l2_ctrl_config flash_timeout;
> + u32 flash_faults;
> +};
> +
> +/**
> + * struct v4l2_flash - Flash sub-device context
> + * @flash: LED Flash Class device controlled by this sub-device
> + * @ops: LED Flash Class device ops
> + * @sd: V4L2 sub-device
> + * @hdl: flash controls handler
> + * @ctrl: state defining controls
> + * @config: V4L2 Flash controlsrconfiguration data
> + * @software_strobe_gates: route to the software strobe signal
> + * @external_strobe_gates: route to the external strobe signal
> + * @sensors: available external strobe sources
> + */
> +struct v4l2_flash {
> + struct led_classdev_flash *flash;
> + const struct v4l2_flash_ops *ops;
> +
> + struct v4l2_subdev sd;
> + struct v4l2_ctrl_handler hdl;
> + struct v4l2_flash_ctrl ctrl;
> + struct v4l2_flash_ctrl_config config;
> + char **strobe_providers_menu;
> +};
> +
> +static inline struct v4l2_flash *v4l2_subdev_to_v4l2_flash(
> + struct v4l2_subdev *sd)
> +{
> + return container_of(sd, struct v4l2_flash, sd);
> +}
> +
> +static inline struct v4l2_flash *v4l2_ctrl_to_v4l2_flash(struct v4l2_ctrl *c)
> +{
> + return container_of(c->handler, struct v4l2_flash, hdl);
> +}
> +
> +#ifdef CONFIG_V4L2_FLASH_LED_CLASS
> +/**
> + * v4l2_flash_init - initialize V4L2 flash led sub-device
> + * @led_fdev: the LED Flash Class device to wrap
> + * @config: initialization data for V4L2 Flash controls
> + * @flash_ops: V4L2 Flash device ops
> + * @out_flash: handler to the new V4L2 Flash device
> + *
> + * Create V4L2 subdev wrapping given LED subsystem device.
> +
> + * Returns: 0 on success or negative error value on failure
> + */
> +int v4l2_flash_init(struct led_classdev_flash *led_fdev,
> + struct v4l2_flash_ctrl_config *config,
> + const struct v4l2_flash_ops *flash_ops,
> + struct v4l2_flash **out_flash);
> +
> +/**
> + * v4l2_flash_release - release V4L2 Flash sub-device
> + * @flash: the V4L2 Flash device to release
> + *
> + * Release V4L2 flash led subdev.
> + */
> +void v4l2_flash_release(struct v4l2_flash *v4l2_flash);
> +
> +#else
> +#define v4l2_flash_init(led_cdev, config, flash_ops, out_flash) (0)
> +#define v4l2_flash_release(v4l2_flash)
> +#endif /* CONFIG_V4L2_FLASH_LED_CLASS */
> +
> +#endif /* _V4L2_FLASH_H */
>
--
Kind regards,
Sakari Ailus
sakari.ailus@xxxxxx
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