From nobody Tue Apr 7 23:45:14 2026 Received: from metis.whiteo.stw.pengutronix.de (metis.whiteo.stw.pengutronix.de [185.203.201.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 823A33D88F2 for ; Wed, 11 Mar 2026 12:27:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.201.7 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773232057; cv=none; b=Os53h9QnTWJVX54X3dzK1a2xVz+9DjdqXhhUBI2pi3t4v3wC2kQU4JL48jDCVfI0UKZoKCkGTnhph8ZUNSruPHe9F1oqhdlzG4uu22IhOtLKofjq60fSMM0zuMflXdYuyCabe0tM8pMMnBnLay9Y97drpgnK5jnQVFlXoSg7H5Y= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773232057; c=relaxed/simple; bh=gGHm4R+DqstAdiyoqIK+LYoWHwK4l7grCC17b0tMOIY=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=CwZEVe4cnH7LapmuOL7nrOWfGYnIPQKZVDuN7JwQkb03CDGVMvUKyGh1/yWzueHRrDFz9mp+oXUV5WrHSM5+ER+y4psGlfQW1j2jDHfrOxartErEvLWyfhxF08RSjSZsbGZuaIx6R7I5Z0FtpWQHHm1lOplJKehxmO4awsZZzS4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.201.7 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=ratatoskr.trumtrar.info) by metis.whiteo.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1w0If0-0002PX-3P; Wed, 11 Mar 2026 13:27:34 +0100 From: Steffen Trumtrar Date: Wed, 11 Mar 2026 13:27:02 +0100 Subject: [PATCH v2 2/2] leds: lp5860: detect and report fault state Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260311-v6-19-topic-ti-lp5860-fault-v2-2-f9454910f009@pengutronix.de> References: <20260311-v6-19-topic-ti-lp5860-fault-v2-0-f9454910f009@pengutronix.de> In-Reply-To: <20260311-v6-19-topic-ti-lp5860-fault-v2-0-f9454910f009@pengutronix.de> To: Lee Jones , Pavel Machek Cc: linux-kernel@vger.kernel.org, linux-leds@vger.kernel.org, Steffen Trumtrar X-Mailer: b4 0.14.3 X-SA-Exim-Connect-IP: 2a0a:edc0:0:900:1d::77 X-SA-Exim-Mail-From: s.trumtrar@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org The lp5860 can detect shorts and open circuits. If an open (LOD) or short (LSD) is detected, the global bit in LP5860_FAULT_STATE is set. The channel that caused this can be read from the corresponding Dot_lsdX and Dot_lodX register and bit offset. The global bits can be cleared by writing 0xf to the LOD/LSD_clear register. Signed-off-by: Steffen Trumtrar --- drivers/leds/rgb/leds-lp5860-core.c | 143 ++++++++++++++++++++++++++= ++++ include/linux/platform_data/leds-lp5860.h | 19 +++- 2 files changed, 159 insertions(+), 3 deletions(-) diff --git a/drivers/leds/rgb/leds-lp5860-core.c b/drivers/leds/rgb/leds-lp= 5860-core.c index 28b4d86e11f1a..b62a1db18c05b 100644 --- a/drivers/leds/rgb/leds-lp5860-core.c +++ b/drivers/leds/rgb/leds-lp5860-core.c @@ -19,6 +19,149 @@ static struct lp5860_led *mcled_cdev_to_led(struct led_= classdev_mc *mc_cdev) return container_of(mc_cdev, struct lp5860_led, mc_cdev); } =20 +static const char *lp5860_led_name(struct lp5860 *lp, unsigned int idx) +{ + for (int i =3D 0; i < lp->leds_count; i++) { + struct mc_subled *mc_led_info; + struct lp5860_led *led; + + led =3D &lp->leds[i]; + + mc_led_info =3D led->mc_cdev.subled_info; + + for (int j =3D 0; j < led->mc_cdev.num_colors; j++) { + if (mc_led_info[j].channel =3D=3D idx) + return led->mc_cdev.led_cdev.dev->kobj.name; + } + } + + return 0; +} + +static ssize_t lp5860_get_fault_state(struct lp5860 *led, char *buf, + unsigned int reg, unsigned int length) +{ + int len =3D 0; + + for (unsigned int dot =3D 0; dot < length; dot++) { + unsigned int offset =3D 0; + unsigned int value; + unsigned int max_bits; + int ret; + + ret =3D regmap_read(led->regmap, reg + dot, &value); + if (ret) + return ret; + + max_bits =3D BITS_PER_BYTE; + /* Every 3rd Dot_x register only has 2 bits */ + if (dot % 3 =3D=3D 2) + max_bits =3D 2; + + for (unsigned int bit =3D 0; bit < max_bits; bit++) { + offset++; + + if (value & BIT(bit)) { + len +=3D sprintf(buf + len, "%s:%d", lp5860_led_name(led, offset), + offset - 1); + len +=3D sprintf(buf + len, " "); + } + } + } + + buf[len++] =3D '\n'; + + return len; +} + +static ssize_t lp5860_fault_state_open_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct lp5860 *led =3D dev_get_drvdata(dev); + unsigned int value; + int ret; + + ret =3D regmap_read(led->regmap, LP5860_REG_FAULT_STATE, &value); + if (ret) + return ret; + + if (!(value & LP5860_FAULT_STATE_OPEN_DETECTION)) + return 0; + + return lp5860_get_fault_state(led, buf, LP5860_REG_DOT_LOD_START, + LP5860_DOT_LOD_LENGTH); +} +static LP5860_DEV_ATTR_R(fault_state_open); + +static ssize_t lp5860_fault_state_short_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct lp5860 *led =3D dev_get_drvdata(dev); + unsigned int value; + int ret; + + ret =3D regmap_read(led->regmap, LP5860_REG_FAULT_STATE, &value); + if (ret) + return ret; + + if (!(value & LP5860_FAULT_STATE_SHORT_DETECTION)) + return 0; + + return lp5860_get_fault_state(led, buf, LP5860_REG_DOT_LSD_START, + LP5860_DOT_LSD_LENGTH); +} +static LP5860_DEV_ATTR_R(fault_state_short); + +static ssize_t lp5860_fault_state_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct lp5860 *led =3D dev_get_drvdata(dev); + unsigned int value; + int ret; + + ret =3D regmap_read(led->regmap, LP5860_REG_FAULT_STATE, &value); + if (ret) + return ret; + + return sysfs_emit(buf, "%d\n", (value & 0x3)); +} + +static ssize_t lp5860_fault_state_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct lp5860 *led =3D dev_get_drvdata(dev); + unsigned int value =3D 0; + int ret; + + if (kstrtoint(buf, 0, &value)) + return -EINVAL; + + if (value & LP5860_FAULT_STATE_OPEN_DETECTION) + ret =3D regmap_write(led->regmap, LP5860_REG_LOD_CLEAR, 0xf); + + if (value & LP5860_FAULT_STATE_SHORT_DETECTION) + ret =3D regmap_write(led->regmap, LP5860_REG_LSD_CLEAR, 0xf); + + if (ret < 0) + return ret; + + return len; +} +static LP5860_DEV_ATTR_RW(fault_state); + +static struct attribute *lp5860_led_attrs[] =3D { + &dev_attr_fault_state_open.attr, + &dev_attr_fault_state_short.attr, + &dev_attr_fault_state.attr, + NULL, +}; + +static const struct attribute_group lp5860_led_group =3D { + .attrs =3D lp5860_led_attrs, +}; + static int lp5860_set_dot_onoff(struct lp5860_led *led, unsigned int dot, = bool enable) { unsigned int offset =3D dot / LP5860_MAX_DOT_ONOFF_GROUP_NUM; diff --git a/include/linux/platform_data/leds-lp5860.h b/include/linux/plat= form_data/leds-lp5860.h index 7bc69a7a550dd..7b2cc88d70e24 100644 --- a/include/linux/platform_data/leds-lp5860.h +++ b/include/linux/platform_data/leds-lp5860.h @@ -188,7 +188,9 @@ #define LP5860_DOT_CS_ON 0x01 #define LP5860_DOT_CS_OFF 0x00 =20 -/* Dot lod value */ +/* Dot LED open detection (LOD) value */ +#define LP5860_FAULT_STATE_OPEN_DETECTION BIT(1) + #define LP5860_DOT_LOD0_OFFSET 0 #define LP5860_DOT_LOD1_OFFSET 1 #define LP5860_DOT_LOD2_OFFSET 2 @@ -201,7 +203,11 @@ #define LP5860_DOT_LOD_ON 0x01 #define LP5860_DOT_LOD_OFF 0x00 =20 -/* dot lsd value */ +#define LP5860_DOT_LOD_LENGTH 0x20 + +/* Dot LED short detection (LSD) value */ +#define LP5860_FAULT_STATE_SHORT_DETECTION BIT(0) + #define LP5860_DOT_LSD0_OFFSET 0 #define LP5860_DOT_LSD1_OFFSET 1 #define LP5860_DOT_LSD2_OFFSET 2 @@ -214,7 +220,8 @@ #define LP5860_DOT_LSD_ON 0x01 #define LP5860_DOT_LSD_OFF 0x00 =20 -/* Register lod state */ +#define LP5860_DOT_LSD_LENGTH 0x20 + #define LP5860_GLOBAL_LOD_OFFSET 1 #define LP5860_GLOBAL_LOD_STATE BIT(1) #define LP5860_GLOBAL_LSD_OFFSET 0 @@ -248,6 +255,12 @@ */ #define LP5860_MAX_LED_CHANNELS 4 =20 +#define LP5860_DEV_ATTR_R(name) \ + DEVICE_ATTR(name, 0444, lp5860_##name##_show, NULL) + +#define LP5860_DEV_ATTR_RW(name) \ + DEVICE_ATTR(name, 0644, lp5860_##name##_show, lp5860_##name##_store) + struct lp5860_led { struct lp5860 *chip; struct led_classdev_mc mc_cdev; --=20 2.51.0