On 6/27/22 09:43, Lee Jones wrote:
> On Mon, 27 Jun 2022, Greg Kroah-Hartman wrote:
>
>> On Mon, Jun 27, 2022 at 03:04:32PM +0100, Lee Jones wrote:
>>> USB review please.
>>>
>>>> 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;
>>>> +};
>>
>>
>> Looks sane enough, but doesn't actually do any USB data transfers, maybe
>> that happens somewhere else...
>
> I expect those to happen in *both* of these:
>
> static const struct mfd_cell ch341_devs[] = {
> {
> .name = "ch341-gpio",
> },
> {
> .name = "ch341-i2c",
> },
> };
>
> Is that correct Frank?
Yes, that's correct.
Frank
