Introduce the LM36274 LED driver.  This driver uses the ti-lmu
MFD driver to probe this LED driver.  The driver configures only the
LED registers and enables the outputs according to the config file.

The driver utilizes the ti-lmu-led-common framework to set the brightness
bits.

Signed-off-by: Dan Murphy <dmur...@ti.com>
---

v2 - No changes - https://lore.kernel.org/patchwork/patch/1058778/

 drivers/leds/Kconfig        |   9 +-
 drivers/leds/Makefile       |   1 +
 drivers/leds/leds-lm36274.c | 174 ++++++++++++++++++++++++++++++++++++
 3 files changed, 183 insertions(+), 1 deletion(-)
 create mode 100644 drivers/leds/leds-lm36274.c

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 2d1576f4d5d6..c0bf59544886 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -783,12 +783,19 @@ config LEDS_LM3697
          Say Y to enable the LM3697 LED driver for TI LMU devices.
          This supports the LED device LM3697.
 
+config LEDS_LM36274
+       tristate "LED driver for LM36274"
+       depends on LEDS_TI_LMU_COMMON
+       help
+         Say Y to enable the LM36274 LED driver for TI LMU devices.
+         This supports the LED device LM36274.
+
 config LEDS_TI_LMU_COMMON
        tristate "LED driver for TI LMU"
        help
           Say Y to enable the LED driver for TI LMU devices.
           This supports common features between the TI LM3532, LM3631, LM3632,
-         LM3633, LM3695 and LM3697.
+         LM3633, LM3695, LM3697 and LM36274
 
 comment "LED Triggers"
 source "drivers/leds/trigger/Kconfig"
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 2eb0225d8dc6..7ff67215b38c 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -81,6 +81,7 @@ obj-$(CONFIG_LEDS_LM3692X)            += leds-lm3692x.o
 obj-$(CONFIG_LEDS_SC27XX_BLTC)         += leds-sc27xx-bltc.o
 obj-$(CONFIG_LEDS_LM3601X)             += leds-lm3601x.o
 obj-$(CONFIG_LEDS_LM3697)              += leds-lm3697.o
+obj-$(CONFIG_LEDS_LM36274)             += leds-lm36274.o
 obj-$(CONFIG_LEDS_TI_LMU_COMMON)       += ti-lmu-led-common.o
 
 # LED SPI Drivers
diff --git a/drivers/leds/leds-lm36274.c b/drivers/leds/leds-lm36274.c
new file mode 100644
index 000000000000..6a419c47c47f
--- /dev/null
+++ b/drivers/leds/leds-lm36274.c
@@ -0,0 +1,174 @@
+// SPDX-License-Identifier: GPL-2.0
+// TI LM36274 LED chip family driver
+// Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/leds.h>
+#include <linux/ti-lmu-led-common.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+
+#include <linux/mfd/ti-lmu.h>
+#include <linux/mfd/ti-lmu-register.h>
+
+#include <uapi/linux/uleds.h>
+
+#define LM36274_MAX_STRINGS    4
+#define LM36274_BL_EN          BIT(4)
+
+/**
+ * struct lm36274
+ * @pdev: platform device
+ * @led_dev: led class device
+ * @lmu_data: Register and setting values for common code
+ * @regmap: Devices register map
+ * @dev: Pointer to the devices device struct
+ * @led_sources - The LED strings supported in this array
+ * @num_leds - Number of LED strings are supported in this array
+ */
+struct lm36274 {
+       struct platform_device *pdev;
+       struct led_classdev led_dev;
+       struct ti_lmu_bank lmu_data;
+       struct regmap *regmap;
+       struct device *dev;
+
+       u32 led_sources[LM36274_MAX_STRINGS];
+       int num_leds;
+};
+
+static int lm36274_brightness_set(struct led_classdev *led_cdev,
+                               enum led_brightness brt_val)
+{
+       struct lm36274 *led = container_of(led_cdev, struct lm36274, led_dev);
+
+       return ti_lmu_common_set_brightness(&led->lmu_data, brt_val);
+}
+
+static int lm36274_init(struct lm36274 *lm36274_data)
+{
+       int enable_val = 0;
+       int i;
+
+       for (i = 0; i < lm36274_data->num_leds; i++)
+               enable_val |= (1 << lm36274_data->led_sources[i]);
+
+       if (!enable_val) {
+               dev_err(lm36274_data->dev, "No LEDs were enabled\n");
+               return -EINVAL;
+       }
+
+       enable_val |= LM36274_BL_EN;
+
+       return regmap_write(lm36274_data->regmap, LM36274_REG_BL_EN,
+                           enable_val);
+}
+
+static int lm36274_parse_dt(struct lm36274 *lm36274_data)
+{
+       struct fwnode_handle *child = NULL;
+       char label[LED_MAX_NAME_SIZE];
+       struct device *dev = &lm36274_data->pdev->dev;
+       const char *name;
+       int child_cnt;
+       int ret = -EINVAL;
+
+       /* There should only be 1 node */
+       child_cnt = device_get_child_node_count(dev);
+       if (child_cnt != 1)
+               return ret;
+
+       device_for_each_child_node(dev, child) {
+               ret = fwnode_property_read_string(child, "label", &name);
+               if (ret)
+                       snprintf(label, sizeof(label),
+                               "%s::", lm36274_data->pdev->name);
+               else
+                       snprintf(label, sizeof(label),
+                                "%s:%s", lm36274_data->pdev->name, name);
+
+               lm36274_data->num_leds = fwnode_property_read_u32_array(child,
+                                                         "led-sources",
+                                                         NULL, 0);
+               if (lm36274_data->num_leds <= 0)
+                       return -ENODEV;
+
+               ret = fwnode_property_read_u32_array(child, "led-sources",
+                                                    lm36274_data->led_sources,
+                                                    lm36274_data->num_leds);
+               if (ret) {
+                       dev_err(dev, "led-sources property missing\n");
+                       return -EINVAL;
+               }
+
+               fwnode_property_read_string(child, "linux,default-trigger",
+                                       &lm36274_data->led_dev.default_trigger);
+
+       }
+
+       lm36274_data->lmu_data.regmap = lm36274_data->regmap;
+       lm36274_data->lmu_data.max_brightness = MAX_BRIGHTNESS_11BIT;
+       lm36274_data->lmu_data.msb_brightness_reg = LM36274_REG_BRT_MSB;
+       lm36274_data->lmu_data.lsb_brightness_reg = LM36274_REG_BRT_LSB;
+
+       lm36274_data->led_dev.name = label;
+       lm36274_data->led_dev.max_brightness = MAX_BRIGHTNESS_11BIT;
+       lm36274_data->led_dev.brightness_set_blocking = lm36274_brightness_set;
+
+       return ret;
+}
+
+static int lm36274_probe(struct platform_device *pdev)
+{
+       struct ti_lmu *lmu = dev_get_drvdata(pdev->dev.parent);
+       struct lm36274 *lm36274_data;
+       int ret;
+
+       lm36274_data = devm_kzalloc(&pdev->dev, sizeof(*lm36274_data),
+                                   GFP_KERNEL);
+       if (!lm36274_data) {
+               ret = -ENOMEM;
+               return ret;
+       }
+
+       lm36274_data->pdev = pdev;
+       lm36274_data->dev = lmu->dev;
+       lm36274_data->regmap = lmu->regmap;
+       dev_set_drvdata(&pdev->dev, lm36274_data);
+
+       ret = lm36274_parse_dt(lm36274_data);
+       if (ret) {
+               dev_err(lm36274_data->dev, "Failed to parse DT node\n");
+               return ret;
+       }
+
+       ret = lm36274_init(lm36274_data);
+       if (ret) {
+               dev_err(lm36274_data->dev, "Failed to init the device\n");
+               return ret;
+       }
+
+       return devm_led_classdev_register(lm36274_data->dev,
+                                        &lm36274_data->led_dev);
+}
+
+static const struct of_device_id of_lm36274_leds_match[] = {
+       { .compatible = "ti,lm36274-backlight", },
+       {},
+};
+MODULE_DEVICE_TABLE(of, of_lm36274_leds_match);
+
+static struct platform_driver lm36274_driver = {
+       .probe  = lm36274_probe,
+       .driver = {
+               .name = "lm36274-leds",
+       },
+};
+module_platform_driver(lm36274_driver)
+
+MODULE_DESCRIPTION("Texas Instruments LM36274 LED driver");
+MODULE_AUTHOR("Dan Murphy <dmur...@ti.com>");
+MODULE_LICENSE("GPL v2");
-- 
2.21.0.5.gaeb582a983

Reply via email to