Driver obtains LED devices according to system configuration and creates
devices in form: "devicename:color:function", like
The full path is to be:
/sys/class/leds/mlxreg\:status\:amber/brightness
After timer trigger activation:
echo timer > /sys/class/leds/mlxreg\:status\:amber/trigger
Attributes for LED blinking will appaer in sysfs infrastructure:
/sys/class/leds/mlxreg\:status\:amber/delay_off
/sys/class/leds/mlxreg\:status\:amber/delay_on
LED setting is controlled through the on-board programmable devices,
which exports its register map. This device could be attached to any
bus type, for which register mapping is supported.
Signed-off-by: Vadim Pasternak <vadimp@xxxxxxxxxxxx>
Acked-by: Pavel Machek <pavel@xxxxxx>
---
v4->v5
Comments pointed out by Jacek:
- Make consistent naming in mlxreg_led_brightness_set,
mlxreg_led_brightness_get, mlxreg_led_config;
- Remove unnecessary data assignment in mlxreg_led_config;
Changes added by Vadim:
- Add internal structure mlxreg_led_data to leds-mlxreg.c;
v3->v4
Comments pointed out by Jacek:
- add led in declaration mlxreg_led_store_hw and mlxreg_led_get_hw;
- rearrange local variables names in mlxreg_led_config;
Comments pointed out by Pavel:
- replace _HALF/_FULL with BLINK_3HZ/BLINK_6HZ;
- in mlxreg_led_get_hw just return after access error;
- explicit check for green led is not added, since control device can be
programmed for blue LED and this case it reuses masks of green LED.
v2->v3:
Comments pointed out by Jacek:
- fix order in includes;
- add declaration pdata in mlxreg_led_store_hw and mlxreg_led_get_hw;
- add declaration of led_data in mlxreg_led_config;
- use LED_ON in assignment instead of 1;
- fix mutex call in mlxreg_led_remove;
v1->v2:
Comments pointed out by Jacek:
- remove macros MLXREG_MAP and MLXREG_CDEV;
- brightness_set_blocking insteaf of brightness_set, this fix allows
removing of context validation and workqueue and also three fields from
struct mlxreg_core_led_data in mlxreg.h;
- remove MLXREG_LED_NAME;
- extend Kconfig description;
Changes added by Vadim:
- remove unnecessary includes after dropping workqueue;
---
MAINTAINERS | 1 +
drivers/leds/Kconfig | 10 ++
drivers/leds/Makefile | 1 +
drivers/leds/leds-mlxreg.c | 317 +++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 329 insertions(+)
create mode 100644 drivers/leds/leds-mlxreg.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 205d397..ac6b0d0 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8566,6 +8566,7 @@ M: Vadim Pasternak <vadimp@xxxxxxxxxxxx>
L: linux-leds@xxxxxxxxxxxxxxx
S: Supported
F: drivers/leds/leds-mlxcpld.c
+F: drivers/leds/leds-mlxreg.c
F: Documentation/leds/leds-mlxcpld.txt
MELLANOX PLATFORM DRIVER
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 594b24d..1c6563d 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -657,6 +657,16 @@ config LEDS_MLXCPLD
This option enabled support for the LEDs on the Mellanox
boards. Say Y to enabled these.
+config LEDS_MLXREG
+ tristate "LED support for the Mellanox BMC cards"
+ depends on LEDS_CLASS
+ help
+ This option enabled support for the LEDs on the Mellanox BMC cards.
+ The driver can be activated from the device tree or by the direct
+ platform device add call. Say Y to enabled these. To compile this
+ driver as a module, choose 'M' here: the module will be called
+ leds-mlxreg.
+
config LEDS_USER
tristate "Userspace LED support"
depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 909dae6..3eb76e5 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -69,6 +69,7 @@ obj-$(CONFIG_LEDS_IS31FL319X) += leds-is31fl319x.o
obj-$(CONFIG_LEDS_IS31FL32XX) += leds-is31fl32xx.o
obj-$(CONFIG_LEDS_PM8058) += leds-pm8058.o
obj-$(CONFIG_LEDS_MLXCPLD) += leds-mlxcpld.o
+obj-$(CONFIG_LEDS_MLXREG) += leds-mlxreg.o
obj-$(CONFIG_LEDS_NIC78BX) += leds-nic78bx.o
obj-$(CONFIG_LEDS_MT6323) += leds-mt6323.o
diff --git a/drivers/leds/leds-mlxreg.c b/drivers/leds/leds-mlxreg.c
new file mode 100644
index 0000000..6b93425
--- /dev/null
+++ b/drivers/leds/leds-mlxreg.c
@@ -0,0 +1,317 @@
+/*
+ * Copyright (c) 2017 Mellanox Technologies. All rights reserved.
+ * Copyright (c) 2017 Vadim Pasternak <vadimp@xxxxxxxxxxxx>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_data/mlxreg.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+/* Codes for LEDs. */
+#define MLXREG_LED_OFFSET_BLINK_3HZ 0x01 /* Offset from solid: 3Hz blink */
+#define MLXREG_LED_OFFSET_BLINK_6HZ 0x02 /* Offset from solid: 6Hz blink */
+#define MLXREG_LED_IS_OFF 0x00 /* Off */
+#define MLXREG_LED_RED_SOLID 0x05 /* Solid red */
+#define MLXREG_LED_GREEN_SOLID 0x0D /* Solid green */
+#define MLXREG_LED_AMBER_SOLID 0x09 /* Solid amber */
+#define MLXREG_LED_BLINK_3HZ 167 /* ~167 msec off/on - HW support */
+#define MLXREG_LED_BLINK_6HZ 83 /* ~83 msec off/on - HW support */
+
+/**
+ * struct mlxreg_led_data - led control data:
+ *
+ * @data: led configuration data;
+ * @led_classdev: led class data;
+ * @base_color: base led color (other colors have constant offset from base);
+ * @led_data: led data;
+ * @data_parent: pointer to private device control data of parent;
+ */
+struct mlxreg_led_data {
+ struct mlxreg_core_data *data;
+ struct led_classdev led_cdev;
+ u8 base_color;
+ void *data_parent;
+ char led_cdev_name[MLXREG_CORE_LABEL_MAX_SIZE];
+};
+
+#define cdev_to_priv(c) container_of(c, struct mlxreg_led_data, led_cdev)
+
+/**
+ * struct mlxreg_led_priv_data - platform private data:
+ *
+ * @pdev: platform device;
+ * @pdata: platform data;
+ * @access_lock: mutex for attribute IO access;
+ */
+struct mlxreg_led_priv_data {
+ struct platform_device *pdev;
+ struct mlxreg_core_led_platform_data *pdata;
+ struct mutex access_lock; /* protect IO operations */
+};
+
+static int
+mlxreg_led_store_hw(struct mlxreg_led_data *led_data, u8 vset)
+{
+ struct mlxreg_led_priv_data *priv = led_data->data_parent;
+ struct mlxreg_core_led_platform_data *led_pdata = priv->pdata;
+ struct mlxreg_core_data *data = led_data->data;
+ u32 regval;
+ u32 nib;
+ int ret;
+
+ /*
+ * Each LED is controlled through low or high nibble of the relevant
+ * register byte. Register offset is specified by off parameter.
+ * Parameter vset provides color code: 0x0 for off, 0x5 for solid red,
+ * 0x6 for 3Hz blink red, 0xd for solid green, 0xe for 3Hz blink
+ * green.
+ * Parameter mask specifies which nibble is used for specific LED: mask
+ * 0xf0 - lower nibble is to be used (bits from 0 to 3), mask 0x0f -
+ * higher nibble (bits from 4 to 7).
+ */
+ mutex_lock(&priv->access_lock);
+
+ ret = regmap_read(led_pdata->regmap, data->reg, ®val);
+ if (ret)
+ goto access_error;
+
+ nib = (ror32(data->mask, data->bit) == 0xf0) ? rol32(vset, data->bit) :
+ rol32(vset, data->bit + 4);
+ regval = (regval & data->mask) | nib;
+
+ ret = regmap_write(led_pdata->regmap, data->reg, regval);
+
+access_error:
+ mutex_unlock(&priv->access_lock);
+
+ return ret;
+}
+
+static enum led_brightness
+mlxreg_led_get_hw(struct mlxreg_led_data *led_data)
+{
+ struct mlxreg_led_priv_data *priv = led_data->data_parent;
+ struct mlxreg_core_led_platform_data *led_pdata = priv->pdata;
+ struct mlxreg_core_data *data = led_data->data;
+ u32 regval;
+ int ret;
+
+ /*
+ * Each LED is controlled through low or high nibble of the relevant
+ * register byte. Register offset is specified by off parameter.
+ * Parameter vset provides color code: 0x0 for off, 0x5 for solid red,
+ * 0x6 for 3Hz blink red, 0xd for solid green, 0xe for 3Hz blink
+ * green.
+ * Parameter mask specifies which nibble is used for specific LED: mask
+ * 0xf0 - lower nibble is to be used (bits from 0 to 3), mask 0x0f -
+ * higher nibble (bits from 4 to 7).
+ */
+ ret = regmap_read(led_pdata->regmap, data->reg, ®val);
+ if (ret < 0) {
+ dev_warn(led_data->led_cdev.dev, "Failed to get current brightness, error: %d\n",
+ ret);
+ /* Assume the LED is OFF */
+ return LED_OFF;
+ }
+
+ regval = regval & ~data->mask;
+ regval = (ror32(data->mask, data->bit) == 0xf0) ? ror32(regval,
+ data->bit) : ror32(regval, data->bit + 4);
+ if (regval >= led_data->base_color &&
+ regval <= (led_data->base_color + MLXREG_LED_OFFSET_BLINK_6HZ))
+ ret = LED_FULL;
+ else
+ ret = LED_OFF;
+
+ return ret;
+}
+
+static int
+mlxreg_led_brightness_set(struct led_classdev *cled, enum led_brightness value)
+{
+ struct mlxreg_led_data *led_data = cdev_to_priv(cled);
+
+ if (value)
+ return mlxreg_led_store_hw(led_data, led_data->base_color);
+ else
+ return mlxreg_led_store_hw(led_data, MLXREG_LED_IS_OFF);
+}
+
+static enum led_brightness
+mlxreg_led_brightness_get(struct led_classdev *cled)
+{
+ struct mlxreg_led_data *led_data = cdev_to_priv(cled);
+
+ return mlxreg_led_get_hw(led_data);
+}
+
+static int
+mlxreg_led_blink_set(struct led_classdev *cled, unsigned long *delay_on,
+ unsigned long *delay_off)
+{
+ struct mlxreg_led_data *led_data = cdev_to_priv(cled);
+ int err;
+
+ /*
+ * HW supports two types of blinking: full (6Hz) and half (3Hz).
+ * For delay on/off zero LED is setting to solid color. For others
+ * combination blinking is to be controlled by the software timer.
+ */
+ if (!(*delay_on == 0 && *delay_off == 0) &&
+ !(*delay_on == MLXREG_LED_BLINK_3HZ &&
+ *delay_off == MLXREG_LED_BLINK_3HZ) &&
+ !(*delay_on == MLXREG_LED_BLINK_6HZ &&
+ *delay_off == MLXREG_LED_BLINK_6HZ))
+ return -EINVAL;
+
+ if (*delay_on == MLXREG_LED_BLINK_6HZ)
+ err = mlxreg_led_store_hw(led_data, led_data->base_color +
+ MLXREG_LED_OFFSET_BLINK_6HZ);
+ else if (*delay_on == MLXREG_LED_BLINK_3HZ)
+ err = mlxreg_led_store_hw(led_data, led_data->base_color +
+ MLXREG_LED_OFFSET_BLINK_3HZ);
+ else
+ err = mlxreg_led_store_hw(led_data, led_data->base_color);
+
+ return err;
+}
+
+static int mlxreg_led_config(struct mlxreg_led_priv_data *priv)
+{
+ struct mlxreg_core_led_platform_data *led_pdata = priv->pdata;
+ struct mlxreg_core_data *data = led_pdata->data;
+ struct mlxreg_led_data *led_data;
+ struct led_classdev *led_cdev;
+ int brightness;
+ int i;
+ int err;
+
+ for (i = 0; i < led_pdata->counter; i++, data++) {
+ led_data = devm_kzalloc(&priv->pdev->dev, sizeof(*led_data),
+ GFP_KERNEL);
+ if (!led_data)
+ return -ENOMEM;
+
+ led_cdev = &led_data->led_cdev;
+ led_data->data_parent = priv;
+ if (strstr(data->label, "red")) {
+ brightness = LED_OFF;
+ led_data->base_color = MLXREG_LED_RED_SOLID;
+ } else if (strstr(data->label, "amber")) {
+ brightness = LED_OFF;
+ led_data->base_color = MLXREG_LED_AMBER_SOLID;
+ } else {
+ brightness = LED_OFF;
+ led_data->base_color = MLXREG_LED_GREEN_SOLID;
+ }
+ sprintf(led_data->led_cdev_name, "%s:%s", "mlxreg",
+ data->label);
+ led_cdev->name = led_data->led_cdev_name;
+ led_cdev->brightness = brightness;
+ led_cdev->max_brightness = LED_ON;
+ led_cdev->brightness_set_blocking =
+ mlxreg_led_brightness_set;
+ led_cdev->brightness_get = mlxreg_led_brightness_get;
+ led_cdev->blink_set = mlxreg_led_blink_set;
+ led_cdev->flags = LED_CORE_SUSPENDRESUME;
+ led_data->data = data;
+ err = devm_led_classdev_register(&priv->pdev->dev, led_cdev);
+ if (err)
+ return err;
+
+ if (led_cdev->brightness)
+ mlxreg_led_brightness_set(led_cdev,
+ led_cdev->brightness);
+ dev_info(led_cdev->dev, "label: %s, mask: 0x%02x, offset:0x%02x\n",
+ data->label, data->mask, data->reg);
+ }
+
+ return 0;
+}
+
+static int mlxreg_led_probe(struct platform_device *pdev)
+{
+ struct mlxreg_core_led_platform_data *led_pdata;
+ struct mlxreg_led_priv_data *priv;
+
+ led_pdata = dev_get_platdata(&pdev->dev);
+ if (!led_pdata) {
+ dev_err(&pdev->dev, "Failed to get platform data.\n");
+ return -EINVAL;
+ }
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ mutex_init(&priv->access_lock);
+ priv->pdev = pdev;
+ priv->pdata = led_pdata;
+
+ return mlxreg_led_config(priv);
+}
+
+static int mlxreg_led_remove(struct platform_device *pdev)
+{
+ struct mlxreg_led_priv_data *priv = dev_get_drvdata(&pdev->dev);
+
+ mutex_destroy(&priv->access_lock);
+
+ return 0;
+}
+
+static const struct of_device_id mlxreg_led_dt_match[] = {
+ { .compatible = "mellanox,leds-mlxreg" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, mlxreg_dt_match);
+
+static struct platform_driver mlxreg_led_driver = {
+ .driver = {
+ .name = "leds-mlxreg",
+ .of_match_table = of_match_ptr(mlxreg_led_dt_match),
+ },
+ .probe = mlxreg_led_probe,
+ .remove = mlxreg_led_remove,
+};
+
+module_platform_driver(mlxreg_led_driver);
+
+MODULE_AUTHOR("Vadim Pasternak <vadimp@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Mellanox LED regmap driver");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_ALIAS("platform:leds-mlxreg");
--
2.1.4
