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path: root/drivers/leds/leds-mlxreg.c
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-rw-r--r--drivers/leds/leds-mlxreg.c301
1 files changed, 301 insertions, 0 deletions
diff --git a/drivers/leds/leds-mlxreg.c b/drivers/leds/leds-mlxreg.c
new file mode 100644
index 000000000..b7855c93b
--- /dev/null
+++ b/drivers/leds/leds-mlxreg.c
@@ -0,0 +1,301 @@
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+//
+// Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+// Copyright (c) 2018 Vadim Pasternak <vadimp@mellanox.com>
+
+#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 */
+#define MLXREG_LED_CAPABILITY_CLEAR GENMASK(31, 8) /* Clear mask */
+
+/**
+ * struct mlxreg_led_data - led control data:
+ *
+ * @data: led configuration data;
+ * @led_cdev: 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;
+ * @led_cdev_name: class device name
+ */
+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_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_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, &regval);
+ 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_platform_data *led_pdata = priv->pdata;
+ struct mlxreg_core_data *data = led_data->data;
+ u32 regval;
+ int err;
+
+ /*
+ * 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).
+ */
+ err = regmap_read(led_pdata->regmap, data->reg, &regval);
+ if (err < 0) {
+ dev_warn(led_data->led_cdev.dev, "Failed to get current brightness, error: %d\n",
+ err);
+ /* 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))
+ return LED_FULL;
+
+ return LED_OFF;
+}
+
+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_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;
+ enum led_brightness brightness;
+ u32 regval;
+ 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;
+
+ if (data->capability) {
+ err = regmap_read(led_pdata->regmap, data->capability,
+ &regval);
+ if (err) {
+ dev_err(&priv->pdev->dev, "Failed to query capability register\n");
+ return err;
+ }
+ if (!(regval & data->bit))
+ continue;
+ /*
+ * Field "bit" can contain one capability bit in 0 byte
+ * and offset bit in 1-3 bytes. Clear capability bit and
+ * keep only offset bit.
+ */
+ data->bit &= MLXREG_LED_CAPABILITY_CLEAR;
+ }
+
+ led_cdev = &led_data->led_cdev;
+ led_data->data_parent = priv;
+ if (strstr(data->label, "red") ||
+ strstr(data->label, "orange")) {
+ 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;
+ }
+ snprintf(led_data->led_cdev_name, sizeof(led_data->led_cdev_name),
+ "mlxreg:%s", 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_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 struct platform_driver mlxreg_led_driver = {
+ .driver = {
+ .name = "leds-mlxreg",
+ },
+ .probe = mlxreg_led_probe,
+ .remove = mlxreg_led_remove,
+};
+
+module_platform_driver(mlxreg_led_driver);
+
+MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>");
+MODULE_DESCRIPTION("Mellanox LED regmap driver");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_ALIAS("platform:leds-mlxreg");