The CH341 is a multifunction chip, presenting 3 different USB PID. One
of these functions is for I2C/SPI/GPIO. This new set of drivers will
manage I2C and GPIO.
Signed-off-by: frank zago <frank@xxxxxxxx>
---
MAINTAINERS | 7 +++
drivers/mfd/Kconfig | 10 +++++
drivers/mfd/Makefile | 1 +
drivers/mfd/ch341-core.c | 90 +++++++++++++++++++++++++++++++++++++++
include/linux/mfd/ch341.h | 18 ++++++++
5 files changed, 126 insertions(+)
create mode 100644 drivers/mfd/ch341-core.c
create mode 100644 include/linux/mfd/ch341.h
diff --git a/MAINTAINERS b/MAINTAINERS
index 43d3d07afccd..628eeaa9bf68 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -21475,6 +21475,13 @@ M: David Härdeman <david@xxxxxxxxxxx>
S: Maintained
F: drivers/media/rc/winbond-cir.c
+WINCHIPHEAD CH341 I2C/GPIO MFD DRIVER
+M: Frank Zago <frank@xxxxxxxx>
+L: linux-usb@xxxxxxxxxxxxxxx
+S: Maintained
+F: drivers/mfd/ch341-core.c
+F: include/linux/mfd/ch341.h
+
WINSYSTEMS EBC-C384 WATCHDOG DRIVER
M: William Breathitt Gray <vilhelm.gray@xxxxxxxxx>
L: linux-watchdog@xxxxxxxxxxxxxxx
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 3b59456f5545..893acc821a42 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1784,6 +1784,16 @@ config MFD_LOCHNAGAR
help
Support for Cirrus Logic Lochnagar audio development board.
+config MFD_CH341
+ tristate "WinChipHead CH341 in I2C/SPI/GPIO mode"
+ depends on USB
+ help
+ If you say yes to this option, support for the CH341 series
+ of chips, running in I2C/SPI/GPIO mode will be included.
+
+ This driver can also be built as a module. If so, the
+ module will be called ch341-core.
+
config MFD_ARIZONA
select REGMAP
select REGMAP_IRQ
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 858cacf659d6..fd615ab3929f 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_MFD_ASIC3) += asic3.o tmio_core.o
obj-$(CONFIG_ARCH_BCM2835) += bcm2835-pm.o
obj-$(CONFIG_MFD_BCM590XX) += bcm590xx.o
obj-$(CONFIG_MFD_BD9571MWV) += bd9571mwv.o
+obj-$(CONFIG_MFD_CH341) += ch341-core.o
obj-$(CONFIG_MFD_CROS_EC_DEV) += cros_ec_dev.o
obj-$(CONFIG_MFD_ENE_KB3930) += ene-kb3930.o
obj-$(CONFIG_MFD_EXYNOS_LPASS) += exynos-lpass.o
diff --git a/drivers/mfd/ch341-core.c b/drivers/mfd/ch341-core.c
new file mode 100644
index 000000000000..f08a67dd6074
--- /dev/null
+++ b/drivers/mfd/ch341-core.c
@@ -0,0 +1,90 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Core driver for the CH341A, CH341B and CH341T in I2C/SPI/GPIO
+ * mode. There are cell drivers available for I2C and GPIO. SPI is not
+ * yet supported.
+ *
+ * Copyright 2022, Frank Zago
+ * Copyright (c) 2017 Gunar Schorcht (gunar@xxxxxxxxxxxx)
+ * Copyright (c) 2016 Tse Lun Bien
+ * Copyright (c) 2014 Marco Gittler
+ * Copyright (c) 2006-2007 Till Harbaum (Till@xxxxxxxxxxx)
+ */
+
+#include <linux/kernel.h>
+#include <linux/mfd/ch341.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+
+static const struct mfd_cell ch341_devs[] = {
+ {
+ .name = "ch341-gpio",
+ },
+ {
+ .name = "ch341-i2c",
+ },
+};
+
+static int ch341_usb_probe(struct usb_interface *iface,
+ const struct usb_device_id *usb_id)
+{
+ struct usb_endpoint_descriptor *bulk_out;
+ struct usb_endpoint_descriptor *bulk_in;
+ struct usb_endpoint_descriptor *intr_in;
+ struct ch341_ddata *ddata;
+ int ret;
+
+ ddata = devm_kzalloc(&iface->dev, sizeof(*ddata), GFP_KERNEL);
+ if (!ddata)
+ return -ENOMEM;
+
+ ddata->usb_dev = interface_to_usbdev(iface);
+ mutex_init(&ddata->usb_lock);
+
+ ret = usb_find_common_endpoints(iface->cur_altsetting, &bulk_in,
+ &bulk_out, &intr_in, NULL);
+ if (ret) {
+ dev_err(&iface->dev, "Could not find all endpoints\n");
+ return -ENODEV;
+ }
+
+ ddata->ep_in = bulk_in->bEndpointAddress;
+ ddata->ep_out = bulk_out->bEndpointAddress;
+ ddata->ep_intr = intr_in->bEndpointAddress;
+ ddata->ep_intr_interval = intr_in->bInterval;
+
+ usb_set_intfdata(iface, ddata);
+
+ ret = mfd_add_devices(&iface->dev, PLATFORM_DEVID_AUTO, ch341_devs,
+ ARRAY_SIZE(ch341_devs), NULL, 0, NULL);
+ if (ret)
+ return dev_err_probe(&iface->dev, ret,
+ "Failed to register child devices\n");
+
+ return 0;
+}
+
+static void ch341_usb_disconnect(struct usb_interface *usb_if)
+{
+ mfd_remove_devices(&usb_if->dev);
+}
+
+static const struct usb_device_id ch341_usb_table[] = {
+ { USB_DEVICE(0x1a86, 0x5512) },
+ { }
+};
+MODULE_DEVICE_TABLE(usb, ch341_usb_table);
+
+static struct usb_driver ch341_usb_driver = {
+ .name = "ch341-mfd",
+ .id_table = ch341_usb_table,
+ .probe = ch341_usb_probe,
+ .disconnect = ch341_usb_disconnect,
+};
+module_usb_driver(ch341_usb_driver);
+
+MODULE_AUTHOR("Frank Zago <frank@xxxxxxxx>");
+MODULE_DESCRIPTION("CH341 USB to I2C/SPI/GPIO adapter");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mfd/ch341.h b/include/linux/mfd/ch341.h
new file mode 100644
index 000000000000..44f5da0720bd
--- /dev/null
+++ b/include/linux/mfd/ch341.h
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Definitions for the CH341 driver */
+
+#include <linux/mutex.h>
+#include <linux/types.h>
+
+struct usb_device;
+struct usb_interface;
+
+struct ch341_ddata {
+ struct usb_device *usb_dev;
+ struct mutex usb_lock;
+
+ int ep_in;
+ int ep_out;
+ int ep_intr;
+ u8 ep_intr_interval;
+};
--
2.32.0
