Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
MAINTAINERS | 6 ++
drivers/platform/x86/Kconfig | 21 ++++
drivers/platform/x86/Makefile | 1 +
drivers/platform/x86/intel_atomisp2_led.c | 118 ++++++++++++++++++++++
4 files changed, 146 insertions(+)
create mode 100644 drivers/platform/x86/intel_atomisp2_led.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 2926327e4976..d85e009260ec 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8499,6 +8499,12 @@ L: platform-driver-x86@xxxxxxxxxxxxxxx
S: Maintained
F: drivers/platform/x86/intel_atomisp2_pm.c
+INTEL ATOMISP2 LED DRIVER
+M: Hans de Goede <hdegoede@xxxxxxxxxx>
+L: platform-driver-x86@xxxxxxxxxxxxxxx
+S: Maintained
+F: drivers/platform/x86/intel_atomisp2_led.c
+
INTEL C600 SERIES SAS CONTROLLER DRIVER
M: Intel SCU Linux support <intel-linux-scu@xxxxxxxxx>
M: Artur Paszkiewicz <artur.paszkiewicz@xxxxxxxxx>
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 0ad7ad8cf8e1..1af4c97447a2 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -750,6 +750,27 @@ config INTEL_ATOMISP2_PM
To compile this driver as a module, choose M here: the module
will be called intel_atomisp2_pm.
+config INTEL_ATOMISP2_LED
+ tristate "Intel AtomISP2 camera LED driver"
+ depends on GPIOLIB && LEDS_GPIO
+ help
+ Many Bay Trail and Cherry Trail devices come with a camera attached
+ to Intel's Image Signal Processor. Linux currently does not have a
+ driver for these, so they do not work as a camera. Some of these
+ camera's have a LED which is controlled through a GPIO.
+
+ Some of these devices have a firmware issue where the LED gets turned
+ on at boot. This driver will turn the LED off at boot and also allows
+ controlling the LED (repurposing it) through the sysfs LED interface.
+
+ Which GPIO is attached to the LED is usually not described in the
+ ACPI tables, so this driver contains per-system info about the GPIO
+ inside the driver, this means that this driver only works on systems
+ the driver knows about.
+
+ To compile this driver as a module, choose M here: the module
+ will be called intel_atomisp2_led.
+
config INTEL_CHT_INT33FE
tristate "Intel Cherry Trail ACPI INT33FE Driver"
depends on X86 && ACPI && I2C && REGULATOR
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 53408d965874..969581237abb 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -69,6 +69,7 @@ obj-$(CONFIG_THINKPAD_ACPI) += thinkpad_acpi.o
# Intel
obj-$(CONFIG_INTEL_ATOMISP2_PM) += intel_atomisp2_pm.o
+obj-$(CONFIG_INTEL_ATOMISP2_LED) += intel_atomisp2_led.o
obj-$(CONFIG_INTEL_CHT_INT33FE) += intel_cht_int33fe.o
intel_cht_int33fe-objs := intel_cht_int33fe_common.o \
intel_cht_int33fe_typec.o \
diff --git a/drivers/platform/x86/intel_atomisp2_led.c b/drivers/platform/x86/intel_atomisp2_led.c
new file mode 100644
index 000000000000..fb704956cd9d
--- /dev/null
+++ b/drivers/platform/x86/intel_atomisp2_led.c
@@ -0,0 +1,118 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Driver for controlling LEDs for cameras connected to the Intel atomisp2
+ * The main purpose of this driver is to turn off LEDs which are on at boot.
+ *
+ * Copyright (C) 2020 Hans de Goede <hdegoede@xxxxxxxxxx>
+ */
+
+#include <linux/dmi.h>
+#include <linux/gpio/consumer.h>
+#include <linux/gpio/machine.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+#include <linux/workqueue.h>
+
+/* This must be leds-gpio as the leds-gpio driver binds to the name */
+#define DEV_NAME "leds-gpio"
+
+static const struct gpio_led atomisp2_leds[] = {
+ {
+ .name = "atomisp2::camera",
+ .default_state = LEDS_GPIO_DEFSTATE_OFF,
+ },
+};
+
+static const struct gpio_led_platform_data atomisp2_leds_pdata = {
+ .num_leds = ARRAY_SIZE(atomisp2_leds),
+ .leds = atomisp2_leds,
+};
+
+static struct gpiod_lookup_table asus_t100ta_lookup = {
+ .dev_id = DEV_NAME,
+ .table = {
+ GPIO_LOOKUP_IDX("INT33FC:02", 8, NULL, 0, GPIO_ACTIVE_HIGH),
+ { }
+ }
+};
+
+static struct gpiod_lookup_table asus_t100chi_lookup = {
+ .dev_id = DEV_NAME,
+ .table = {
+ GPIO_LOOKUP_IDX("INT33FC:01", 24, NULL, 0, GPIO_ACTIVE_HIGH),
+ { }
+ }
+};
+
+static const struct dmi_system_id atomisp2_led_systems[] __initconst = {
+ {
+ .matches = {
+ DMI_EXACT_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
+ DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "T100TA"),
+ },
+ .driver_data = &asus_t100ta_lookup,
+ },
+ {
+ .matches = {
+ DMI_EXACT_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
+ DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "T200TA"),
+ },
+ .driver_data = &asus_t100ta_lookup,
+ },
+ {
+ .matches = {
+ DMI_EXACT_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
+ DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "T100CHI"),
+ },
+ .driver_data = &asus_t100chi_lookup,
+ },
+ {} /* Terminating entry */
+};
+MODULE_DEVICE_TABLE(dmi, atomisp2_led_systems);
+
+static struct gpiod_lookup_table *gpio_lookup;
+static struct platform_device *pdev;
+
+static int __init atomisp2_led_init(void)
+{
+ const struct dmi_system_id *system;
+
+ system = dmi_first_match(atomisp2_led_systems);
+ if (!system)
+ return -ENODEV;
+
+ gpio_lookup = system->driver_data;
+ gpiod_add_lookup_table(gpio_lookup);
+
+ pdev = platform_device_register_resndata(NULL,
+ DEV_NAME, PLATFORM_DEVID_NONE,
+ NULL, 0, &atomisp2_leds_pdata,
+ sizeof(atomisp2_leds_pdata));
+ if (IS_ERR(pdev)) {
+ gpiod_remove_lookup_table(gpio_lookup);
+ return PTR_ERR(pdev);
+ }
+
+ return 0;
+}
+
+static void __exit atomisp2_led_cleanup(void)
+{
+ platform_device_unregister(pdev);
+ gpiod_remove_lookup_table(gpio_lookup);
+}
+
+module_init(atomisp2_led_init);
+module_exit(atomisp2_led_cleanup);
+
+/*
+ * The ACPI INIT method from Asus WMI's code on the T100TA and T200TA turns the
+ * LED on (without the WMI interface allowing further control over the LED).
+ * Ensure we are loaded after asus-nb-wmi so that we turn the LED off again.
+ */
+MODULE_SOFTDEP("pre: asus_nb_wmi");
+MODULE_AUTHOR("Hans de Goede <hdegoede@xxxxxxxxxx");
+MODULE_DESCRIPTION("Intel atomisp2 camera LED driver");
+MODULE_LICENSE("GPL");
--
2.26.0
