Driver obtains LED devices according to system configuration, provided
through the platform data, like mlxreg:status:green or mlxreg:status:amber
and creates devices in form: "devicename:colour:function".
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>
---
MAINTAINERS | 1 +
drivers/leds/Makefile | 1 +
drivers/leds/leds-mlxreg.c | 345 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 347 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/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..bc1a6c3
--- /dev/null
+++ b/drivers/leds/leds-mlxreg.c
@@ -0,0 +1,345 @@
+/*
+ * 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/interrupt.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/of_device.h>
+#include <linux/platform_data/mlxreg.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+
+#define MLXREG_LED_NAME "mlxreg"
+
+/* Codes for LEDs. */
+#define MLXREG_LED_OFFSET_HALF 0x01 /* Offset from solid: 3Hz blink */
+#define MLXREG_LED_OFFSET_FULL 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 */
+#define MLXREG_LED_MAX_DEFERRED 32 /* Max deferred operations for LED set */
+
+#define cdev_to_priv(c) container_of(c, struct mlxreg_core_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 */
+};
+
+#define MLXREG_MAP priv->pdata->regmap
+
+static int
+mlxreg_led_store_hw(struct mlxreg_core_led_data *led_pdata, u8 vset)
+{
+ struct mlxreg_led_priv_data *priv = led_pdata->data_parent;
+ 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(MLXREG_MAP, led_pdata->led->reg, ®val);
+ if (ret)
+ goto access_error;
+
+ nib = (ror32(led_pdata->led->mask, led_pdata->led->bit) == 0xf0) ?
+ rol32(vset, led_pdata->led->bit) :
+ rol32(vset, led_pdata->led->bit + 4);
+ regval = (regval & led_pdata->led->mask) | nib;
+
+ ret = regmap_write(MLXREG_MAP, led_pdata->led->reg, regval);
+
+access_error:
+ mutex_unlock(&priv->access_lock);
+
+ return ret;
+}
+
+static enum led_brightness
+mlxreg_led_get_hw(struct mlxreg_core_led_data *led_pdata)
+{
+ struct mlxreg_led_priv_data *priv = led_pdata->data_parent;
+ 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(MLXREG_MAP, led_pdata->led->reg, ®val);
+ if (ret < 0) {
+ dev_warn(led_pdata->led_cdev.dev, "Failed to get current brightness, error: %d\n",
+ ret);
+ /* Assume the LED is OFF */
+ ret = LED_OFF;
+ goto access_error;
+ }
+
+ regval = regval & ~led_pdata->led->mask;
+ regval = (ror32(led_pdata->led->mask, led_pdata->led->bit) == 0xf0) ?
+ ror32(regval, led_pdata->led->bit) :
+ ror32(regval, led_pdata->led->bit + 4);
+ if (regval >= led_pdata->base_color &&
+ regval <= (led_pdata->base_color + MLXREG_LED_OFFSET_FULL))
+ ret = LED_FULL;
+ else
+ ret = LED_OFF;
+
+access_error:
+
+ return ret;
+}
+
+static void
+mlxreg_led_brightness_set(struct led_classdev *cled, enum led_brightness value)
+{
+ struct mlxreg_core_led_data *led_pdata = cdev_to_priv(cled);
+
+ if (in_interrupt()) {
+ /*
+ * Handle hw access to LED in workqueue to avoid I2C locking in
+ * interrupt mode. Skip if deferred operations counter is at
+ * maximum value.
+ */
+ if (led_pdata->set_count == MLXREG_LED_MAX_DEFERRED - 1)
+ return;
+
+ if (!!value)
+ led_pdata->bitset |= BIT(led_pdata->set_count);
+ led_pdata->set_count++;
+
+ schedule_delayed_work(&led_pdata->dwork_led, 0);
+
+ return;
+ }
+
+ if (value)
+ mlxreg_led_store_hw(led_pdata, led_pdata->base_color);
+ else
+ mlxreg_led_store_hw(led_pdata, MLXREG_LED_IS_OFF);
+}
+
+static enum led_brightness
+mlxreg_led_brightness_get(struct led_classdev *cled)
+{
+ struct mlxreg_core_led_data *led_pdata = cdev_to_priv(cled);
+
+ return mlxreg_led_get_hw(led_pdata);
+}
+
+static int
+mlxreg_led_blink_set(struct led_classdev *cled, unsigned long *delay_on,
+ unsigned long *delay_off)
+{
+ struct mlxreg_core_led_data *led_pdata = 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_pdata, led_pdata->base_color +
+ MLXREG_LED_OFFSET_FULL);
+ else if (*delay_on == MLXREG_LED_BLINK_3HZ)
+ err = mlxreg_led_store_hw(led_pdata, led_pdata->base_color +
+ MLXREG_LED_OFFSET_HALF);
+ else
+ err = mlxreg_led_store_hw(led_pdata, led_pdata->base_color);
+
+ return err;
+}
+
+static void mlxreg_led_handler(struct work_struct *work)
+{
+ struct mlxreg_core_led_data *led_pdata = container_of(work,
+ struct mlxreg_core_led_data, dwork_led.work);
+
+ if (led_pdata->bitset & BIT(0))
+ mlxreg_led_store_hw(led_pdata, led_pdata->base_color);
+ else
+ mlxreg_led_store_hw(led_pdata, MLXREG_LED_IS_OFF);
+
+ led_pdata->bitset >>= 1;
+ led_pdata->set_count--;
+}
+
+#define MLXREG_CDEV(i) pdata->data[i].led_cdev
+
+static int mlxreg_led_config(struct mlxreg_led_priv_data *priv)
+{
+ struct mlxreg_core_led_platform_data *pdata = priv->pdata;
+ struct mlxreg_core_data *data = pdata->data->led;
+ int brightness;
+ int i;
+ int err;
+
+ for (i = 0; i < pdata->counter; i++, data++) {
+ pdata->data[i].data_parent = priv;
+ if (strstr(data->label, "red")) {
+ brightness = LED_OFF;
+ pdata->data[i].base_color = MLXREG_LED_RED_SOLID;
+ } else if (strstr(data->label, "amber")) {
+ brightness = LED_OFF;
+ pdata->data[i].base_color = MLXREG_LED_AMBER_SOLID;
+ } else {
+ brightness = LED_OFF;
+ pdata->data[i].base_color = MLXREG_LED_GREEN_SOLID;
+ }
+ sprintf(pdata->data[i].led_cdev_name, "%s:%s",
+ MLXREG_LED_NAME, data->label);
+ MLXREG_CDEV(i).name = pdata->data[i].led_cdev_name;
+ MLXREG_CDEV(i).brightness = brightness;
+ MLXREG_CDEV(i).max_brightness = 1;
+ MLXREG_CDEV(i).brightness_set = mlxreg_led_brightness_set;
+ MLXREG_CDEV(i).brightness_get = mlxreg_led_brightness_get;
+ MLXREG_CDEV(i).blink_set = mlxreg_led_blink_set;
+ MLXREG_CDEV(i).flags = LED_CORE_SUSPENDRESUME;
+ pdata->data[i].led = data;
+ err = devm_led_classdev_register(&priv->pdev->dev,
+ &MLXREG_CDEV(i));
+ if (err)
+ return err;
+
+ if (MLXREG_CDEV(i).brightness)
+ mlxreg_led_brightness_set(
+ &MLXREG_CDEV(i),
+ MLXREG_CDEV(i).brightness);
+ dev_info(MLXREG_CDEV(i).dev,
+ "label: %s, mask: 0x%02x, offset:0x%02x\n",
+ data->label, data->mask, data->reg);
+
+ INIT_DELAYED_WORK(&pdata->data[i].dwork_led,
+ mlxreg_led_handler);
+ }
+
+ return 0;
+}
+
+static int mlxreg_led_probe(struct platform_device *pdev)
+{
+ struct mlxreg_core_led_platform_data *pdata;
+ struct mlxreg_led_priv_data *priv;
+
+ pdata = dev_get_platdata(&pdev->dev);
+ if (!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 = 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);
+ struct mlxreg_core_led_platform_data *pdata = priv->pdata;
+ int i;
+
+ for (i = 0; i < pdata->counter; i++)
+ cancel_delayed_work(&pdata->data[i].dwork_led);
+
+ mutex_unlock(&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
