drivers/spi/spidev.c                          |   1 -
 7 files changed, 640 insertions(+), 1 deletion(-)
 create mode 100644 Documentation/ABI/testing/sysfs-driver-ge-achc
 create mode 100644 drivers/misc/gehc-achc.c
 create mode 100644 drivers/misc/nxp-ezport.c
 create mode 100644 drivers/misc/nxp-ezport.h

diff --git a/Documentation/ABI/testing/sysfs-driver-ge-achc b/Documentation/ABI/testing/sysfs-driver-ge-achc
new file mode 100644
index 000000000000..f02812731082
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-driver-ge-achc

@@ -0,0 +1,14 @@
+What:		/sys/bus/spi/<dev>/update_firmware
+Date:		Jul 2021
+Contact:	sebastian.reichel@collabora.com
+Description:	Write 1 to this file to update the ACHC microcontroller
+		firmware via the EzPort interface. For this the kernel
+		will load "achc.bin" via the firmware API (so usually
+		from /lib/firmware). The write will block until the FW
+		has either been flashed successfully or an error occured.
+
+What:		/sys/bus/spi/<dev>/reset
+Date:		Jul 2021
+Contact:	sebastian.reichel@collabora.com
+Description:	Write 1 to this file to reset the microcontroller via the
+		reset GPIO. The write will block until the reset completes.

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index f4fb5c52b863..1ebf7000671d 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig

@@ -208,6 +208,17 @@ config CS5535_CLOCK_EVENT_SRC
 	  MFGPTs have a better resolution and max interval than the
 	  generic PIT, and are suitable for use as high-res timers.
 
+config GEHC_ACHC
+	tristate "GEHC ACHC support"
+	depends on SPI && SYSFS
+	select FW_LOADER
+	help
+	  Support for GE ACHC microcontroller, that is part of the GE
+	  PPD device.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called gehc-achc.
+
 config HP_ILO
 	tristate "Channel interface driver for the HP iLO processor"
 	depends on PCI

diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index e92a56d4442f..b50180796931 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile

@@ -24,6 +24,8 @@ obj-$(CONFIG_KGDB_TESTS)	+= kgdbts.o
 obj-$(CONFIG_SGI_XP)		+= sgi-xp/
 obj-$(CONFIG_SGI_GRU)		+= sgi-gru/
 obj-$(CONFIG_CS5535_MFGPT)	+= cs5535-mfgpt.o
+obj-$(CONFIG_GEHC_ACHC)		+= gehc-achc-mod.o
+gehc-achc-mod-objs		:= gehc-achc.o nxp-ezport.o

 obj-$(CONFIG_HP_ILO)		+= hpilo.o
 obj-$(CONFIG_APDS9802ALS)	+= apds9802als.o
 obj-$(CONFIG_ISL29003)		+= isl29003.o

diff --git a/drivers/misc/gehc-achc.c b/drivers/misc/gehc-achc.c
new file mode 100644
index 000000000000..893940e7ca4e
--- /dev/null
+++ b/drivers/misc/gehc-achc.c

@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * datasheet: https://www.nxp.com/docs/en/data-sheet/K20P144M120SF3.pdf
+ *
+ * Copyright (C) 2018-2021 Collabora
+ * Copyright (C) 2018-2021 GE Healthcare
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+#include <linux/of.h>
+#include "nxp-ezport.h"
+
+#define ACHC_MAX_FREQ_HZ 300000
+
+struct achc_data {
+	struct spi_device *main;
+	struct spi_device *ezport;
+	struct gpio_desc *reset;
+
+	struct mutex device_lock; /* avoid concurrent device access */
+};
+
+static ssize_t update_firmware_store(struct device *dev, struct device_attribute *attr,
+				     const char *buf, size_t count)
+{
+	struct achc_data *achc = dev_get_drvdata(dev);
+	int ret;
+
+	if (count != 1 || buf[0] != '1')
+		return -EINVAL;