Re: [PATCH] leds: add SGI IP30 led support

From: Dan Murphy
Date: Wed Jan 15 2020 - 08:49:22 EST


Thomas

On 1/15/20 7:05 AM, Thomas Bogendoerfer wrote:
This patch implemenets a driver to support the front panel LEDs of
SGI Octane (IP30) workstations.

Thanks for the patch

Some nitpicks below


Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@xxxxxxx>
---
drivers/leds/Kconfig | 11 ++++++
drivers/leds/Makefile | 1 +
drivers/leds/leds-ip30.c | 82 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 94 insertions(+)
create mode 100644 drivers/leds/leds-ip30.c

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 4b68520ac251..8ef0fe900928 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -836,6 +836,17 @@ config LEDS_LM36274
Say Y to enable the LM36274 LED driver for TI LMU devices.
This supports the LED device LM36274.
+config LEDS_IP30
+ tristate "LED support for SGI Octane machines"
+ depends on LEDS_CLASS
+ depends on SGI_MFD_IOC3
What is the dependency on the MFD?
+ 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 2da39e896ce8..89a527ac8ab6 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -85,6 +85,7 @@ obj-$(CONFIG_LEDS_LM3601X) += leds-lm3601x.o
obj-$(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_IP30) += leds-ip30.o

Extra tab


# 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..b0a83f78c439
--- /dev/null
+++ b/drivers/leds/leds-ip30.c
@@ -0,0 +1,82 @@
+// 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);
+
+ if (value)
+ writel(1, led->reg);
+ else
+ writel(0, 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 = "ip30:white";
This also needs a function as defined in dt-bindings/common.h
+ data->cdev.default_trigger = "default-on";

The name, color, function and trigger can be pulled from the DT or Firmware.

The firmware should contain a node for each LED to be configured.

+ } else {
+ data->cdev.name = "ip30:red";
Same as above
+ data->cdev.default_trigger = "panic";
+ writel(0, data->reg);

Is the LED on by default?

Dan