[PATCH v4] leds: add SGI IP30 led support

From: Thomas Bogendoerfer
Date: Fri Feb 21 2020 - 06:11:36 EST


This patch implemenets a driver to support the front panel LEDs of
SGI Octane (IP30) workstations.

Reviewed-by: Dan Murphy <dmurphy@xxxxxx>
Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@xxxxxxx>
---
Changes in v4:
- simplified ip30led_set by using gated value from led framework

Changes in v3:
- rebased to 5.6-rc2

Changes in v2:
- use led names conforming to include/dt-bindings/leds/common.h
- read LED state from firmware
- leave setting up to user

drivers/leds/Kconfig | 11 ++++++
drivers/leds/Makefile | 1 +
drivers/leds/leds-ip30.c | 77 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 89 insertions(+)
create mode 100644 drivers/leds/leds-ip30.c

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index d82f1dea3711..c664d84e1667 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -846,6 +846,17 @@ config LEDS_TPS6105X
It is a single boost converter primarily for white LEDs and
audio amplifiers.

+config LEDS_IP30
+ tristate "LED support for SGI Octane machines"
+ depends on LEDS_CLASS
+ depends on SGI_MFD_IOC3
+ help
+ This option enables support for the Red and White LEDs of
+ SGI Octane machines.
+
+ To compile this driver as a module, choose M here: the module
+ will be called leds-ip30.
+
comment "LED Triggers"
source "drivers/leds/trigger/Kconfig"

diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index d7e1107753fb..46bd611a03a9 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -86,6 +86,7 @@ obj-$(CONFIG_LEDS_TI_LMU_COMMON) += leds-ti-lmu-common.o
obj-$(CONFIG_LEDS_LM3697) += leds-lm3697.o
obj-$(CONFIG_LEDS_LM36274) += leds-lm36274.o
obj-$(CONFIG_LEDS_TPS6105X) += leds-tps6105x.o
+obj-$(CONFIG_LEDS_IP30) += leds-ip30.o

# LED SPI Drivers
obj-$(CONFIG_LEDS_CR0014114) += leds-cr0014114.o
diff --git a/drivers/leds/leds-ip30.c b/drivers/leds/leds-ip30.c
new file mode 100644
index 000000000000..c5853780a31a
--- /dev/null
+++ b/drivers/leds/leds-ip30.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * LED Driver for SGI Octane machines
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/leds.h>
+
+struct ip30_led {
+ struct led_classdev cdev;
+ u32 __iomem *reg;
+};
+
+static void ip30led_set(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ struct ip30_led *led = container_of(led_cdev, struct ip30_led, cdev);
+
+ writel(value, led->reg);
+}
+
+static int ip30led_create(struct platform_device *pdev, int num)
+{
+ struct resource *res;
+ struct ip30_led *data;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, num);
+ if (!res)
+ return -EBUSY;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->reg = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(data->reg))
+ return PTR_ERR(data->reg);
+
+
+ if (num == 0)
+ data->cdev.name = "white:indicator";
+ else
+ data->cdev.name = "red:indicator";
+
+ data->cdev.brightness = readl(data->reg);
+ data->cdev.max_brightness = 1;
+ data->cdev.brightness_set = ip30led_set;
+
+ return devm_led_classdev_register(&pdev->dev, &data->cdev);
+}
+
+static int ip30led_probe(struct platform_device *pdev)
+{
+ int ret;
+
+ ret = ip30led_create(pdev, 0);
+ if (ret < 0)
+ return ret;
+
+ return ip30led_create(pdev, 1);
+}
+
+static struct platform_driver ip30led_driver = {
+ .probe = ip30led_probe,
+ .driver = {
+ .name = "ip30-leds",
+ },
+};
+
+module_platform_driver(ip30led_driver);
+
+MODULE_AUTHOR("Thomas Bogendoerfer <tbogendoerfer@xxxxxxx>");
+MODULE_DESCRIPTION("SGI Octane LED driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ip30-leds");
--
2.25.0