Re: [PATCH v3] leds: add SGI IP30 led support

From: Dan Murphy
Date: Wed Feb 19 2020 - 12:56:37 EST


Thomas

On 2/19/20 10:05 AM, Thomas Bogendoerfer wrote:
This patch implemenets a driver to support the front panel LEDs of
SGI Octane (IP30) workstations.

Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@xxxxxxx>
---

Sorry for the delay in review I had to go back and review v1 and v2 comments


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 | 80 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 92 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..82453a216f81
--- /dev/null
+++ b/drivers/leds/leds-ip30.c
@@ -0,0 +1,80 @@
+// 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);
+

With max_brightness set to 1 then value will only be either 1 or 0. The LED framework takes care of gating the values.

So this can be writel(value, led->reg);

Otherwise

Reviewed-by: Dan Murphy <dmurphy@xxxxxx>