pt., 1 lut 2019 o 21:15 Dan Murphy [off-list ref] napisał(a):

Hi

On 2/1/19 1:45 PM, Jacek Anaszewski wrote:

quoted

Hi Bartosz,

Thanks for the update.

On 2/1/19 10:47 AM, Bartosz Golaszewski wrote:

quoted

From: Bartosz Golaszewski <redacted>

This adds basic support for LEDs for the max77650 PMIC. The device has
three current sinks for driving LEDs.

Signed-off-by: Bartosz Golaszewski <redacted>
---
  drivers/leds/Kconfig         |   6 ++
  drivers/leds/Makefile        |   1 +
  drivers/leds/leds-max77650.c | 147 +++++++++++++++++++++++++++++++++++
  3 files changed, 154 insertions(+)
  create mode 100644 drivers/leds/leds-max77650.c

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index a72f97fca57b..6e7a8f51eccc 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig

@@ -608,6 +608,12 @@ config LEDS_TLC591XX
        This option enables support for Texas Instruments TLC59108
        and TLC59116 LED controllers.
  +config LEDS_MAX77650
+    tristate "LED support for Maxim MAX77650 PMIC"
+    depends on MFD_MAX77650
+    help
+      LEDs driver for MAX77650 family of PMICs from Maxim Integrated."
+
  config LEDS_MAX77693
      tristate "LED support for MAX77693 Flash"
      depends on LEDS_CLASS_FLASH

diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 4c1b0054f379..f48b2404dbb7 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile

@@ -61,6 +61,7 @@ obj-$(CONFIG_LEDS_MC13783)        += leds-mc13783.o
  obj-$(CONFIG_LEDS_NS2)            += leds-ns2.o
  obj-$(CONFIG_LEDS_NETXBIG)        += leds-netxbig.o
  obj-$(CONFIG_LEDS_ASIC3)        += leds-asic3.o
+obj-$(CONFIG_LEDS_MAX77650)        += leds-max77650.o
  obj-$(CONFIG_LEDS_MAX77693)        += leds-max77693.o
  obj-$(CONFIG_LEDS_MAX8997)        += leds-max8997.o
  obj-$(CONFIG_LEDS_LM355x)        += leds-lm355x.o

diff --git a/drivers/leds/leds-max77650.c b/drivers/leds/leds-max77650.c
new file mode 100644
index 000000000000..6b74ce9cac12
--- /dev/null
+++ b/drivers/leds/leds-max77650.c

@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (C) 2018 BayLibre SAS
+// Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
+//
+// LED driver for MAXIM 77650/77651 charger/power-supply.
+
+#include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/mfd/max77650.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define MAX77650_LED_NUM_LEDS        3
+
+#define MAX77650_LED_A_BASE        0x40
+#define MAX77650_LED_B_BASE        0x43
+
+#define MAX77650_LED_BR_MASK        GENMASK(4, 0)
+#define MAX77650_LED_EN_MASK        GENMASK(7, 6)
+
+#define MAX77650_LED_MAX_BRIGHTNESS    MAX77650_LED_BR_MASK
+
+/* Enable EN_LED_MSTR. */
+#define MAX77650_LED_TOP_DEFAULT    BIT(0)
+
+#define MAX77650_LED_ENABLE        GENMASK(7, 6)
+#define MAX77650_LED_DISABLE        0x00
+
+#define MAX77650_LED_A_DEFAULT        MAX77650_LED_DISABLE
+/* 100% on duty */
+#define MAX77650_LED_B_DEFAULT        GENMASK(3, 0)
+
+struct max77650_led {
+    struct led_classdev cdev;
+    struct regmap *map;
+    unsigned int regA;
+    unsigned int regB;

Please don't use camel case.

Sorry, but this is pointless nitpicking. The registers are referred to
in the manual as LED[012]_A and LED[012]_B so these variable names
reflect that. The difference between ThisKindOfCamelCase and regA/regB
is obvious. It's much more readable than for example rega or reg_a. I
also used the same approach in the regulator module and there were no
complaints.

quoted

quoted

+};
+
+static struct max77650_led *max77650_to_led(struct led_classdev *cdev)
+{
+    return container_of(cdev, struct max77650_led, cdev);
+}
+
+static int max77650_led_brightness_set(struct led_classdev *cdev,
+                       enum led_brightness brightness)
+{
+    struct max77650_led *led = max77650_to_led(cdev);
+    int val, mask;
+

The register value and bits are only 8 bit why an int?

Because regmap_update_bits() deals with 32-bit integers. There's no
hurt and it's less confusing.

quoted

quoted

+    mask = MAX77650_LED_BR_MASK | MAX77650_LED_EN_MASK;
+
+    if (brightness == LED_OFF)
+        val = MAX77650_LED_DISABLE;
+    else
+        val = MAX77650_LED_ENABLE | brightness;
+
+    return regmap_update_bits(led->map, led->regA, mask, val);
+}
+
+static int max77650_led_probe(struct platform_device *pdev)
+{
+    struct device_node *of_node, *child;
+    struct max77650_led *leds, *led;
+    struct device *parent;
+    struct device *dev;
+    struct regmap *map;
+    const char *label;
+    int rv, num_leds;
+    u32 reg;
+
+    dev = &pdev->dev;
+    parent = dev->parent;
+    of_node = dev->of_node;
+
+    if (!of_node)
+        return -ENODEV;
+
+    leds = devm_kcalloc(dev, sizeof(*leds),
+                MAX77650_LED_NUM_LEDS, GFP_KERNEL);
+    if (!leds)
+        return -ENOMEM;
+
+    map = dev_get_regmap(dev->parent, NULL);
+    if (!map)
+        return -ENODEV;
+
+    num_leds = of_get_child_count(of_node);
+    if (!num_leds || num_leds > MAX77650_LED_NUM_LEDS)
+        return -ENODEV;
+
+    for_each_child_of_node(of_node, child) {
+        rv = of_property_read_u32(child, "reg", &reg);

Can we use the fwnode_property_read_u32 call here?
And the same for all below as well?

Of course we can. But why? This is a low-power PMIC. Is there really a
chance that a non-DT system will want to use it? If so - we will be
able to convert it if needed. For now: I'd stick with of_* functions.

quoted

quoted

+        if (rv || reg >= MAX77650_LED_NUM_LEDS)
+            return -EINVAL;
+
+        led = &leds[reg];
+        led->map = map;
+        led->regA = MAX77650_LED_A_BASE + reg;
+        led->regB = MAX77650_LED_B_BASE + reg;
+        led->cdev.brightness_set_blocking = max77650_led_brightness_set;
+        led->cdev.max_brightness = MAX77650_LED_MAX_BRIGHTNESS;
+
+        label = of_get_property(child, "label", NULL);
+        if (!label) {
+            led->cdev.name = "max77650::";
+        } else {
+            led->cdev.name = devm_kasprintf(dev, GFP_KERNEL,
+                            "max77650:%s", label);
+            if (!led->cdev.name)
+                return -ENOMEM;
+        }
+
+        of_property_read_string(child, "linux,default-trigger",
+                    &led->cdev.default_trigger);
+
+        rv = devm_of_led_classdev_register(dev, child, &led->cdev);
+        if (rv)
+            return rv;
+
+        rv = regmap_write(map, led->regA, MAX77650_LED_A_DEFAULT);
+        if (rv)
+            return rv;
+
+        rv = regmap_write(map, led->regB, MAX77650_LED_B_DEFAULT);
+        if (rv)
+            return rv;
+    }
+
+    return regmap_write(map,
+                MAX77650_REG_CNFG_LED_TOP,
+                MAX77650_LED_TOP_DEFAULT);
+}
+
+static struct platform_driver max77650_led_driver = {
+    .driver = {
+        .name = "max77650-led",
+    },
+    .probe = max77650_led_probe,
+};
+module_platform_driver(max77650_led_driver);
+
+MODULE_DESCRIPTION("MAXIM 77650/77651 LED driver");
+MODULE_AUTHOR("Bartosz Golaszewski [off-list ref]");
+MODULE_LICENSE("GPL v2");

Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>

--
------------------
Dan Murphy

Best regards,
Bartosz Golaszewski