Dan, Thank you for the v15. On 10/28/19 7:36 PM, Dan Murphy wrote: > Introduce a multicolor class that groups colored LEDs > within a LED node. > > The multi color class groups monochrome LEDs and allows controlling two > aspects of the final combined color: hue and lightness. The former is > controlled via <color>_intensity files and the latter is controlled > via brightness file. > > Signed-off-by: Dan Murphy <dmurphy@xxxxxx> > --- > .../ABI/testing/sysfs-class-led-multicolor | 36 +++ > Documentation/leds/index.rst | 1 + > Documentation/leds/leds-class-multicolor.rst | 100 +++++++ > drivers/leds/Kconfig | 10 + > drivers/leds/Makefile | 1 + > drivers/leds/led-class-multicolor.c | 271 ++++++++++++++++++ > include/linux/led-class-multicolor.h | 139 +++++++++ > 7 files changed, 558 insertions(+) > create mode 100644 Documentation/ABI/testing/sysfs-class-led-multicolor > create mode 100644 Documentation/leds/leds-class-multicolor.rst > create mode 100644 drivers/leds/led-class-multicolor.c > create mode 100644 include/linux/led-class-multicolor.h > > diff --git a/Documentation/ABI/testing/sysfs-class-led-multicolor b/Documentation/ABI/testing/sysfs-class-led-multicolor > new file mode 100644 > index 000000000000..3d1f9d726c70 > --- /dev/null > +++ b/Documentation/ABI/testing/sysfs-class-led-multicolor > @@ -0,0 +1,36 @@ > +What: /sys/class/leds/<led>/brightness > +Date: Sept 2019 > +KernelVersion: 5.5 > +Contact: Dan Murphy <dmurphy@xxxxxx> > +Description: read/write > + Writing to this file will update all LEDs within the group to a > + calculated percentage of what each color LED intensity is set > + to. The percentage is calculated for each grouped LED via the > + equation below: > + > + led_brightness = brightness * <color>_intensity/<color>_max_intensity > + > + For additional details please refer to > + Documentation/leds/leds-class-multicolor.rst. > + > + The value of the color is from 0 to > + /sys/class/leds/<led>/max_brightness. > + > +What: /sys/class/leds/<led>/colors/<color>_intensity > +Date: Sept 2019 > +KernelVersion: 5.5 > +Contact: Dan Murphy <dmurphy@xxxxxx> > +Description: read/write > + The <color>_intensity file is created based on the color > + defined by the registrar of the class. > + There is one file per color presented. > + > + The value of the color is from 0 to > + /sys/class/leds/<led>/colors/<color>_max_intensity. > + > +What: /sys/class/leds/<led>/colors/<color>_max_intensity > +Date: Sept 2019 > +KernelVersion: 5.5 > +Contact: Dan Murphy <dmurphy@xxxxxx> > +Description: read only > + Maximum intensity level for the LED color. > diff --git a/Documentation/leds/index.rst b/Documentation/leds/index.rst > index 060f4e485897..bc70c6aa7138 100644 > --- a/Documentation/leds/index.rst > +++ b/Documentation/leds/index.rst > @@ -9,6 +9,7 @@ LEDs > > leds-class > leds-class-flash > + leds-class-multicolor > ledtrig-oneshot > ledtrig-transient > ledtrig-usbport > diff --git a/Documentation/leds/leds-class-multicolor.rst b/Documentation/leds/leds-class-multicolor.rst > new file mode 100644 > index 000000000000..c8a224cead51 > --- /dev/null > +++ b/Documentation/leds/leds-class-multicolor.rst > @@ -0,0 +1,100 @@ > +==================================== > +Multi Color LED handling under Linux > +==================================== > + > +Description > +=========== > +The multi color class groups monochrome LEDs and allows controlling two > +aspects of the final combined color: hue and lightness. The former is > +controlled via <color>_intensity files and the latter is controlled > +via brightness file. > + > +For more details on hue and lightness notions please refer to > +https://en.wikipedia.org/wiki/CIECAM02. > + > +Note that intensity files only cache the written value and the actual > +change of hardware state occurs upon writing brightness file. This > +allows for changing many factors of the perceived color in a virtually > +unnoticeable way for the human observer. > + > +Multicolor Class Control > +======================== > +The multicolor class presents the LED groups under a directory called "colors". > +This directory is a child under the LED parent node created by the led_class > +framework. The led_class framework is documented in led-class.rst within this > +documentation directory. > + > +Each colored LED will have two files created under the colors directory > +<color>_intensity and <color>_max_intensity. These files will contain > +one of LED_COLOR_ID_* definitions from the header > +include/dt-bindings/leds/common.h. > + > +Directory Layout Example > +======================== > +root:/sys/class/leds/rgb:grouped_leds# ls -lR colors/ s/rgb/multicolor/ according to the led_colors[LED_COLOR_ID_MULTI]. > +-rw-r--r-- 1 root root 4096 Jul 7 03:10 blue_intensity > +-r--r--r-- 1 root root 4096 Jul 7 03:10 blue_max_intensity > +-rw-r--r-- 1 root root 4096 Jul 7 03:10 green_intensity > +-r--r--r-- 1 root root 4096 Jul 7 03:10 green_max_intensity > +-rw-r--r-- 1 root root 4096 Jul 7 03:10 red_intensity > +-r--r--r-- 1 root root 4096 Jul 7 03:10 red_max_intensity > + [...] > +static int led_multicolor_init_color(struct led_classdev_mc *mcled_cdev, > + int color_id) > +{ > + struct led_classdev *led_cdev = mcled_cdev->led_cdev; > + struct led_mc_color_entry *mc_priv; > + char *intensity_file_name; > + char *max_intensity_file_name; > + size_t len; > + int ret; > + > + mc_priv = devm_kzalloc(led_cdev->dev, sizeof(*mc_priv), GFP_KERNEL); > + if (!mc_priv) > + return -ENOMEM; > + > + mc_priv->led_color_id = color_id; > + mc_priv->mcled_cdev = mcled_cdev; > + > + sysfs_attr_init(&mc_priv->intensity_attr.attr); > + len = strlen(led_colors[color_id]) + strlen(INTENSITY_NAME) + 1; > + intensity_file_name = kzalloc(len, GFP_KERNEL); > + if (!intensity_file_name) > + return -ENOMEM; > + > + snprintf(intensity_file_name, len, "%s%s", > + led_colors[color_id], INTENSITY_NAME); > + mc_priv->intensity_attr.attr.name = intensity_file_name; > + mc_priv->intensity_attr.attr.mode = 0644; > + mc_priv->intensity_attr.store = intensity_store; > + mc_priv->intensity_attr.show = intensity_show; > + ret = sysfs_add_file_to_group(&led_cdev->dev->kobj, > + &mc_priv->intensity_attr.attr, > + led_color_group.name); > + if (ret) > + goto intensity_err_out; > + > + sysfs_attr_init(&mc_priv->max_intensity_attr.attr); > + len = strlen(led_colors[color_id]) + strlen(MAX_INTENSITY_NAME) + 1; > + max_intensity_file_name = kzalloc(len, GFP_KERNEL); > + if (!max_intensity_file_name) { > + ret = -ENOMEM; > + goto intensity_err_out; > + } > + > + snprintf(max_intensity_file_name, len, "%s%s", > + led_colors[color_id], MAX_INTENSITY_NAME); > + mc_priv->max_intensity_attr.attr.name = max_intensity_file_name; > + mc_priv->max_intensity_attr.attr.mode = 0444; > + mc_priv->max_intensity_attr.show = max_intensity_show; > + ret = sysfs_add_file_to_group(&led_cdev->dev->kobj, > + &mc_priv->max_intensity_attr.attr, > + led_color_group.name); > + if (ret) > + goto max_intensity_err_out; > + > + mc_priv->max_intensity = LED_FULL; > + list_add_tail(&mc_priv->list, &mcled_cdev->color_list); I still would prefer dynamically allocated array here. Also there are things I would see differently in the patch 13/19 as already discussed. Nonetheless I am giving my preliminary ack for this series just to give a hint to others to join the review. -- Best regards, Jacek Anaszewski
