From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756382AbcKKRgG (ORCPT ); Fri, 11 Nov 2016 12:36:06 -0500 Received: from vern.gendns.com ([206.190.152.46]:47643 "EHLO vern.gendns.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934730AbcKKRgE (ORCPT ); Fri, 11 Nov 2016 12:36:04 -0500 From: David Lechner To: Jacek Anaszewski , Richard Purdie Cc: David Lechner , linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] leds: uleds: make max_brightness configurable Date: Fri, 11 Nov 2016 11:35:29 -0600 Message-Id: <1478885730-23190-1-git-send-email-david@lechnology.com> X-Mailer: git-send-email 2.7.4 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - vern.gendns.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - lechnology.com X-Get-Message-Sender-Via: vern.gendns.com: authenticated_id: davidmain+lechnology.com/only user confirmed/virtual account not confirmed X-Authenticated-Sender: vern.gendns.com: davidmain@lechnology.com X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This adds support for configuring max_brightness when setting up a userspace LED device. It also requires changing the brightness value returned from a single byte to an integer. Since the uleds driver has not made it into the mainline kernel yet, this is not breaking userspace. Signed-off-by: David Lechner --- drivers/leds/uleds.c | 16 +++++++++++----- include/uapi/linux/uleds.h | 1 + tools/leds/uledmon.c | 5 +++-- 3 files changed, 15 insertions(+), 7 deletions(-) diff --git a/drivers/leds/uleds.c b/drivers/leds/uleds.c index 2bbc73a..5e9e8a1 100644 --- a/drivers/leds/uleds.c +++ b/drivers/leds/uleds.c @@ -39,7 +39,7 @@ struct uleds_device { struct mutex mutex; enum uleds_state state; wait_queue_head_t waitq; - unsigned char brightness; + int brightness; bool new_data; }; @@ -67,7 +67,6 @@ static int uleds_open(struct inode *inode, struct file *file) return -ENOMEM; udev->led_cdev.name = udev->user_dev.name; - udev->led_cdev.max_brightness = LED_FULL; udev->led_cdev.brightness_set = uleds_brightness_set; mutex_init(&udev->mutex); @@ -117,6 +116,12 @@ static ssize_t uleds_write(struct file *file, const char __user *buffer, goto out; } + if (udev->user_dev.max_brightness <= 0) { + ret = -EINVAL; + goto out; + } + udev->led_cdev.max_brightness = udev->user_dev.max_brightness; + ret = devm_led_classdev_register(uleds_misc.this_device, &udev->led_cdev); if (ret < 0) @@ -138,7 +143,7 @@ static ssize_t uleds_read(struct file *file, char __user *buffer, size_t count, struct uleds_device *udev = file->private_data; ssize_t retval; - if (count == 0) + if (count < sizeof(udev->brightness)) return 0; do { @@ -151,9 +156,10 @@ static ssize_t uleds_read(struct file *file, char __user *buffer, size_t count, } else if (!udev->new_data && (file->f_flags & O_NONBLOCK)) { retval = -EAGAIN; } else if (udev->new_data) { - retval = copy_to_user(buffer, &udev->brightness, 1); + retval = copy_to_user(buffer, &udev->brightness, + sizeof(udev->brightness)); udev->new_data = false; - retval = 1; + retval = sizeof(udev->brightness); } mutex_unlock(&udev->mutex); diff --git a/include/uapi/linux/uleds.h b/include/uapi/linux/uleds.h index 2545b79..3788d5e 100644 --- a/include/uapi/linux/uleds.h +++ b/include/uapi/linux/uleds.h @@ -18,6 +18,7 @@ struct uleds_user_dev { char name[LEDS_MAX_NAME_SIZE]; + int max_brightness; }; #endif /* _UAPI__ULEDS_H_ */ diff --git a/tools/leds/uledmon.c b/tools/leds/uledmon.c index 44d8634..163da85 100644 --- a/tools/leds/uledmon.c +++ b/tools/leds/uledmon.c @@ -22,7 +22,7 @@ int main(int argc, char const *argv[]) { struct uleds_user_dev uleds_dev; int fd, ret; - unsigned char brightness; + int brightness; struct timespec ts; if (argc != 2) { @@ -31,6 +31,7 @@ int main(int argc, char const *argv[]) } strncpy(uleds_dev.name, argv[1], LEDS_MAX_NAME_SIZE); + uleds_dev.max_brightness = 100; fd = open("/dev/uleds", O_RDWR); if (fd == -1) { @@ -46,7 +47,7 @@ int main(int argc, char const *argv[]) } while (1) { - ret = read(fd, &brightness, 1); + ret = read(fd, &brightness, sizeof(brightness)); if (ret == -1) { perror("Failed to read from /dev/uleds"); close(fd); -- 2.7.4