* [PATCH v6 0/4] add driver for the WCH CH341 in I2C/GPIO mode
@ 2022-06-16 1:37 frank zago
2022-06-16 1:37 ` [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode frank zago
` (4 more replies)
0 siblings, 5 replies; 18+ messages in thread
From: frank zago @ 2022-06-16 1:37 UTC (permalink / raw)
To: Greg Kroah-Hartman, linux-kernel, Bartosz Golaszewski,
Wolfram Sang, Johan Hovold, linux-usb, Lee Jones, Linus Walleij,
linux-gpio, linux-i2c, frank zago
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.
Changes from v5:
Addressed reviewers' comments.
Better handling of 0-bytes i2c commands
Use of better USB API.
Changes from v4:
I should have addressed all the comments: rework of the GPIO interrupt
handling code to be more modern, changes in Kconfig wording, some code
cleanup.
Driver was tested again with up to 4 of these devices. No
error seen.
Changes from v3:
- really converted to an MFD driver. Driver is now split into 3
modules (MFD+I2C+GPIO).
- minor code cleanups
Changes from v2:
- bug fixes
- more robust USB enumeration
- Changed to an MFD driver as suggested
During testing I found that i2c handles hot removal, but not gpio. The
gpio subsystem will complain with 'REMOVING GPIOCHIP WITH GPIOS STILL
REQUESTED', but it's a gpiolib issue.
Changes from v1:
- Removed double Signed-off-by
- Move Kconfig into the same directory as the driver
frank zago (4):
mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode
gpio: ch341: add GPIO MFD cell driver for the CH341
i2c: ch341: add I2C MFD cell driver for the CH341
docs: misc: add documentation for ch341 driver
Documentation/misc-devices/ch341.rst | 109 ++++++++
Documentation/misc-devices/index.rst | 1 +
MAINTAINERS | 9 +
drivers/gpio/Kconfig | 10 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-ch341.c | 385 +++++++++++++++++++++++++++
drivers/i2c/busses/Kconfig | 10 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-ch341.c | 377 ++++++++++++++++++++++++++
drivers/mfd/Kconfig | 10 +
drivers/mfd/Makefile | 1 +
drivers/mfd/ch341-core.c | 90 +++++++
include/linux/mfd/ch341.h | 26 ++
13 files changed, 1030 insertions(+)
create mode 100644 Documentation/misc-devices/ch341.rst
create mode 100644 drivers/gpio/gpio-ch341.c
create mode 100644 drivers/i2c/busses/i2c-ch341.c
create mode 100644 drivers/mfd/ch341-core.c
create mode 100644 include/linux/mfd/ch341.h
--
2.32.0
^ permalink raw reply [flat|nested] 18+ messages in thread
* [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode
2022-06-16 1:37 [PATCH v6 0/4] add driver for the WCH CH341 in I2C/GPIO mode frank zago
@ 2022-06-16 1:37 ` frank zago
2022-06-27 14:04 ` Lee Jones
2022-07-04 10:09 ` Lee Jones
2022-06-16 1:37 ` [PATCH v6 2/4] gpio: ch341: add GPIO MFD cell driver for the CH341 frank zago
` (3 subsequent siblings)
4 siblings, 2 replies; 18+ messages in thread
From: frank zago @ 2022-06-16 1:37 UTC (permalink / raw)
To: Greg Kroah-Hartman, linux-kernel, Bartosz Golaszewski,
Wolfram Sang, Johan Hovold, linux-usb, Lee Jones, Linus Walleij,
linux-gpio, linux-i2c, frank zago
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@zago.net>
---
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@hardeman.nu>
S: Maintained
F: drivers/media/rc/winbond-cir.c
+WINCHIPHEAD CH341 I2C/GPIO MFD DRIVER
+M: Frank Zago <frank@zago.net>
+L: linux-usb@vger.kernel.org
+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@gmail.com>
L: linux-watchdog@vger.kernel.org
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@schorcht.net)
+ * Copyright (c) 2016 Tse Lun Bien
+ * Copyright (c) 2014 Marco Gittler
+ * Copyright (c) 2006-2007 Till Harbaum (Till@Harbaum.org)
+ */
+
+#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@zago.net>");
+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
^ permalink raw reply related [flat|nested] 18+ messages in thread
* [PATCH v6 2/4] gpio: ch341: add GPIO MFD cell driver for the CH341
2022-06-16 1:37 [PATCH v6 0/4] add driver for the WCH CH341 in I2C/GPIO mode frank zago
2022-06-16 1:37 ` [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode frank zago
@ 2022-06-16 1:37 ` frank zago
2022-06-17 8:29 ` Linus Walleij
2022-06-20 10:25 ` Johan Hovold
2022-06-16 1:37 ` [PATCH v6 3/4] i2c: ch341: add I2C " frank zago
` (2 subsequent siblings)
4 siblings, 2 replies; 18+ messages in thread
From: frank zago @ 2022-06-16 1:37 UTC (permalink / raw)
To: Greg Kroah-Hartman, linux-kernel, Bartosz Golaszewski,
Wolfram Sang, Johan Hovold, linux-usb, Lee Jones, Linus Walleij,
linux-gpio, linux-i2c, frank zago
The GPIO interface offers 16 GPIOs. 6 are read/write, and 10 are
read-only.
Signed-off-by: frank zago <frank@zago.net>
---
MAINTAINERS | 1 +
drivers/gpio/Kconfig | 10 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-ch341.c | 385 ++++++++++++++++++++++++++++++++++++++
include/linux/mfd/ch341.h | 8 +
5 files changed, 405 insertions(+)
create mode 100644 drivers/gpio/gpio-ch341.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 628eeaa9bf68..8b93f6192704 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -21479,6 +21479,7 @@ WINCHIPHEAD CH341 I2C/GPIO MFD DRIVER
M: Frank Zago <frank@zago.net>
L: linux-usb@vger.kernel.org
S: Maintained
+F: drivers/gpio/gpio-ch341.c
F: drivers/mfd/ch341-core.c
F: include/linux/mfd/ch341.h
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index b01961999ced..473b6e7226ca 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -1653,6 +1653,16 @@ endmenu
menu "USB GPIO expanders"
depends on USB
+config GPIO_CH341
+ tristate "CH341 USB to GPIO support"
+ select MFD_CH341
+ help
+ If you say yes to this option, GPIO support will be included for the
+ WCH CH341, a USB to I2C/SPI/GPIO interface.
+
+ This driver can also be built as a module. If so, the module
+ will be called gpio-ch341.
+
config GPIO_VIPERBOARD
tristate "Viperboard GPIO a & b support"
depends on MFD_VIPERBOARD
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 14352f6dfe8e..beef802cbfb1 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_GPIO_BD9571MWV) += gpio-bd9571mwv.o
obj-$(CONFIG_GPIO_BRCMSTB) += gpio-brcmstb.o
obj-$(CONFIG_GPIO_BT8XX) += gpio-bt8xx.o
obj-$(CONFIG_GPIO_CADENCE) += gpio-cadence.o
+obj-$(CONFIG_GPIO_CH341) += gpio-ch341.o
obj-$(CONFIG_GPIO_CLPS711X) += gpio-clps711x.o
obj-$(CONFIG_GPIO_SNPS_CREG) += gpio-creg-snps.o
obj-$(CONFIG_GPIO_CRYSTAL_COVE) += gpio-crystalcove.o
diff --git a/drivers/gpio/gpio-ch341.c b/drivers/gpio/gpio-ch341.c
new file mode 100644
index 000000000000..233dfe1f2ae8
--- /dev/null
+++ b/drivers/gpio/gpio-ch341.c
@@ -0,0 +1,385 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * GPIO cell driver for the CH341A and CH341B chips.
+ *
+ * Copyright 2022, Frank Zago
+ * Copyright (c) 2017 Gunar Schorcht (gunar@schorcht.net)
+ * Copyright (c) 2016 Tse Lun Bien
+ * Copyright (c) 2014 Marco Gittler
+ * Copyright (c) 2006-2007 Till Harbaum (Till@Harbaum.org)
+ */
+
+/*
+ * Notes.
+ *
+ * For the CH341, 0=IN, 1=OUT, but for the GPIO subsystem, 1=IN and
+ * 0=OUT. Translation happens in a couple places.
+ */
+
+#include <linux/gpio/driver.h>
+#include <linux/kernel.h>
+#include <linux/mfd/ch341.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <linux/usb.h>
+
+#define CH341_GPIO_NUM_PINS 16 /* Number of GPIO pins */
+
+/* GPIO chip commands */
+#define CH341_PARA_CMD_STS 0xA0 /* Get pins status */
+#define CH341_CMD_UIO_STREAM 0xAB /* pin IO stream command */
+
+#define CH341_CMD_UIO_STM_OUT 0x80 /* pin IO interface OUT command (D0~D5) */
+#define CH341_CMD_UIO_STM_DIR 0x40 /* pin IO interface DIR command (D0~D5) */
+#define CH341_CMD_UIO_STM_END 0x20 /* pin IO interface END command */
+
+#define CH341_USB_MAX_INTR_SIZE 8
+
+struct ch341_gpio {
+ struct gpio_chip gpio;
+ struct mutex gpio_lock;
+ u16 gpio_dir; /* 1 bit per pin, 0=IN, 1=OUT. */
+ u16 gpio_last_read; /* last GPIO values read */
+ u16 gpio_last_written; /* last GPIO values written */
+ union {
+ u8 gpio_buf[SEG_SIZE];
+ __le16 gpio_buf_status;
+ };
+
+ struct urb *irq_urb;
+ struct usb_anchor irq_urb_out;
+ u8 irq_buf[CH341_USB_MAX_INTR_SIZE];
+ struct irq_chip irq_chip;
+
+ struct ch341_ddata *ddata;
+};
+
+/*
+ * Masks to describe the 16 GPIOs. Pins D0 to D5 (mapped to GPIOs 0 to
+ * 5) can do input/output, but the other pins are input-only.
+ */
+static const u16 pin_can_output = 0b111111;
+
+/* Only GPIO 10 (INT# line) has hardware interrupt */
+#define CH341_GPIO_INT_LINE 10
+
+/* Send a command and get a reply if requested */
+static int gpio_transfer(struct ch341_gpio *dev, int out_len, int in_len)
+{
+ struct ch341_ddata *ddata = dev->ddata;
+ int actual;
+ int ret;
+
+ mutex_lock(&ddata->usb_lock);
+
+ ret = usb_bulk_msg(ddata->usb_dev,
+ usb_sndbulkpipe(ddata->usb_dev, ddata->ep_out),
+ dev->gpio_buf, out_len,
+ &actual, DEFAULT_TIMEOUT_MS);
+ if (ret < 0)
+ goto out_unlock;
+
+ if (in_len == 0)
+ goto out_unlock;
+
+ ret = usb_bulk_msg(ddata->usb_dev,
+ usb_rcvbulkpipe(ddata->usb_dev, ddata->ep_in),
+ dev->gpio_buf, SEG_SIZE, &actual, DEFAULT_TIMEOUT_MS);
+
+out_unlock:
+ mutex_unlock(&ddata->usb_lock);
+
+ if (ret < 0)
+ return ret;
+
+ return actual;
+}
+
+/* Read the GPIO line status. */
+static int read_inputs(struct ch341_gpio *dev)
+{
+ int ret;
+
+ mutex_lock(&dev->gpio_lock);
+
+ dev->gpio_buf[0] = CH341_PARA_CMD_STS;
+
+ ret = gpio_transfer(dev, 1, 1);
+
+ /*
+ * The status command returns 6 bytes of data. Byte 0 has
+ * status for lines 0 to 7, and byte 1 is lines 8 to 15. The
+ * 3rd has the status for the SCL/SDA/SCK pins. The 4th byte
+ * might have some remaining pin status. Byte 5 and 6 content
+ * is unknown.
+ */
+ if (ret == 6)
+ dev->gpio_last_read = le16_to_cpu(dev->gpio_buf_status);
+ else
+ ret = -EIO;
+
+ mutex_unlock(&dev->gpio_lock);
+
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int ch341_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct ch341_gpio *dev = gpiochip_get_data(chip);
+ int ret;
+
+ ret = read_inputs(dev);
+ if (ret)
+ return ret;
+
+ return !!(dev->gpio_last_read & BIT(offset));
+}
+
+static int ch341_gpio_get_multiple(struct gpio_chip *chip,
+ unsigned long *mask, unsigned long *bits)
+{
+ struct ch341_gpio *dev = gpiochip_get_data(chip);
+ int ret;
+
+ ret = read_inputs(dev);
+ if (ret)
+ return ret;
+
+ *bits = dev->gpio_last_read & *mask;
+
+ return 0;
+}
+
+static void write_outputs(struct ch341_gpio *dev)
+{
+ mutex_lock(&dev->gpio_lock);
+
+ /* Only the first 6 lines can output. */
+ dev->gpio_buf[0] = CH341_CMD_UIO_STREAM;
+ dev->gpio_buf[1] = CH341_CMD_UIO_STM_DIR | (dev->gpio_dir & pin_can_output);
+ dev->gpio_buf[2] = CH341_CMD_UIO_STM_OUT |
+ (dev->gpio_last_written & dev->gpio_dir & pin_can_output);
+ dev->gpio_buf[3] = CH341_CMD_UIO_STM_END;
+
+ gpio_transfer(dev, 4, 0);
+
+ mutex_unlock(&dev->gpio_lock);
+}
+
+static void ch341_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+ struct ch341_gpio *dev = gpiochip_get_data(chip);
+
+ if (value)
+ dev->gpio_last_written |= BIT(offset);
+ else
+ dev->gpio_last_written &= ~BIT(offset);
+
+ write_outputs(dev);
+}
+
+static void ch341_gpio_set_multiple(struct gpio_chip *chip,
+ unsigned long *mask, unsigned long *bits)
+{
+ struct ch341_gpio *dev = gpiochip_get_data(chip);
+
+ dev->gpio_last_written = (dev->gpio_last_written & ~*mask) | (*bits & *mask);
+
+ write_outputs(dev);
+}
+
+static int ch341_gpio_get_direction(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ struct ch341_gpio *dev = gpiochip_get_data(chip);
+
+ return !(dev->gpio_dir & BIT(offset));
+}
+
+static int ch341_gpio_direction_input(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ struct ch341_gpio *dev = gpiochip_get_data(chip);
+
+ dev->gpio_dir &= ~BIT(offset);
+
+ write_outputs(dev);
+
+ return 0;
+}
+
+static int ch341_gpio_direction_output(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ struct ch341_gpio *dev = gpiochip_get_data(chip);
+ u16 mask = BIT(offset);
+
+ if (!(pin_can_output & mask))
+ return -EINVAL;
+
+ dev->gpio_dir |= mask;
+
+ ch341_gpio_set(chip, offset, value);
+
+ return 0;
+}
+
+static void ch341_complete_intr_urb(struct urb *urb)
+{
+ struct ch341_gpio *dev = urb->context;
+ int ret;
+
+ if (urb->status) {
+ usb_unanchor_urb(dev->irq_urb);
+ } else {
+ /*
+ * Data is 8 bytes. Byte 0 might be the length of
+ * significant data, which is 3 more bytes. Bytes 1
+ * and 2, and possibly 3, are the pin status. The byte
+ * order is different than for the GET_STATUS
+ * command. Byte 1 is GPIOs 8 to 15, and byte 2 is
+ * GPIOs 0 to 7.
+ */
+
+ handle_nested_irq(irq_find_mapping(dev->gpio.irq.domain,
+ CH341_GPIO_INT_LINE));
+
+ ret = usb_submit_urb(dev->irq_urb, GFP_ATOMIC);
+ if (ret)
+ usb_unanchor_urb(dev->irq_urb);
+ }
+}
+
+static int ch341_gpio_irq_set_type(struct irq_data *data, unsigned int flow_type)
+{
+ const unsigned long offset = irqd_to_hwirq(data);
+
+ if (offset != CH341_GPIO_INT_LINE || flow_type != IRQ_TYPE_EDGE_RISING)
+ return -EINVAL;
+
+ return 0;
+}
+
+static void ch341_gpio_irq_enable(struct irq_data *data)
+{
+ struct ch341_gpio *dev = irq_data_get_irq_chip_data(data);
+ int ret;
+
+ /*
+ * The URB might have just been unlinked in
+ * ch341_gpio_irq_disable, but the completion handler hasn't
+ * been called yet.
+ */
+ if (!usb_wait_anchor_empty_timeout(&dev->irq_urb_out, 5000))
+ usb_kill_anchored_urbs(&dev->irq_urb_out);
+
+ usb_anchor_urb(dev->irq_urb, &dev->irq_urb_out);
+ ret = usb_submit_urb(dev->irq_urb, GFP_KERNEL);
+ if (ret)
+ usb_unanchor_urb(dev->irq_urb);
+}
+
+static void ch341_gpio_irq_disable(struct irq_data *data)
+{
+ struct ch341_gpio *dev = irq_data_get_irq_chip_data(data);
+
+ usb_unlink_urb(dev->irq_urb);
+}
+
+static int ch341_gpio_remove(struct platform_device *pdev)
+{
+ struct ch341_gpio *dev = platform_get_drvdata(pdev);
+
+ usb_kill_anchored_urbs(&dev->irq_urb_out);
+ gpiochip_remove(&dev->gpio);
+ usb_free_urb(dev->irq_urb);
+
+ return 0;
+}
+
+static const struct irq_chip ch341_irqchip = {
+ .name = "CH341",
+ .irq_set_type = ch341_gpio_irq_set_type,
+ .irq_enable = ch341_gpio_irq_enable,
+ .irq_disable = ch341_gpio_irq_disable,
+ .flags = IRQCHIP_IMMUTABLE,
+ GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+static int ch341_gpio_probe(struct platform_device *pdev)
+{
+ struct ch341_ddata *ddata = dev_get_drvdata(pdev->dev.parent);
+ struct gpio_irq_chip *girq;
+ struct ch341_gpio *dev;
+ struct gpio_chip *gpio;
+ int ret;
+
+ dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
+ if (dev == NULL)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, dev);
+ dev->ddata = ddata;
+ mutex_init(&dev->gpio_lock);
+
+ gpio = &dev->gpio;
+ gpio->label = dev_name(&pdev->dev);
+ gpio->parent = &pdev->dev;
+ gpio->owner = THIS_MODULE;
+ gpio->get_direction = ch341_gpio_get_direction;
+ gpio->direction_input = ch341_gpio_direction_input;
+ gpio->direction_output = ch341_gpio_direction_output;
+ gpio->get = ch341_gpio_get;
+ gpio->get_multiple = ch341_gpio_get_multiple;
+ gpio->set = ch341_gpio_set;
+ gpio->set_multiple = ch341_gpio_set_multiple;
+ gpio->base = -1;
+ gpio->ngpio = CH341_GPIO_NUM_PINS;
+ gpio->can_sleep = true;
+
+ girq = &gpio->irq;
+ gpio_irq_chip_set_chip(girq, &ch341_irqchip);
+ girq->handler = handle_simple_irq;
+ girq->default_type = IRQ_TYPE_NONE;
+
+ /* Create an URB for handling interrupt */
+ dev->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!dev->irq_urb)
+ return dev_err_probe(&pdev->dev, -ENOMEM, "Cannot allocate the int URB\n");
+
+ usb_fill_int_urb(dev->irq_urb, ddata->usb_dev,
+ usb_rcvintpipe(ddata->usb_dev, ddata->ep_intr),
+ dev->irq_buf, CH341_USB_MAX_INTR_SIZE,
+ ch341_complete_intr_urb, dev, ddata->ep_intr_interval);
+
+ init_usb_anchor(&dev->irq_urb_out);
+
+ ret = gpiochip_add_data(gpio, dev);
+ if (ret) {
+ ret = dev_err_probe(&pdev->dev, ret, "Could not add GPIO\n");
+ goto release_urb;
+ }
+
+ return 0;
+
+release_urb:
+ usb_free_urb(dev->irq_urb);
+
+ return ret;
+}
+
+static struct platform_driver ch341_gpio_driver = {
+ .driver.name = "ch341-gpio",
+ .probe = ch341_gpio_probe,
+ .remove = ch341_gpio_remove,
+};
+module_platform_driver(ch341_gpio_driver);
+
+MODULE_AUTHOR("Frank Zago <frank@zago.net>");
+MODULE_DESCRIPTION("CH341 USB to GPIO");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ch341-gpio");
diff --git a/include/linux/mfd/ch341.h b/include/linux/mfd/ch341.h
index 44f5da0720bd..804d671fbe45 100644
--- a/include/linux/mfd/ch341.h
+++ b/include/linux/mfd/ch341.h
@@ -4,6 +4,14 @@
#include <linux/mutex.h>
#include <linux/types.h>
+#define DEFAULT_TIMEOUT_MS 1000 /* 1s USB requests timeout */
+
+/*
+ * All commands fit inside a 32-byte segment. There may be several of
+ * these segments in a USB command.
+ */
+#define SEG_SIZE 32
+
struct usb_device;
struct usb_interface;
--
2.32.0
^ permalink raw reply related [flat|nested] 18+ messages in thread
* [PATCH v6 3/4] i2c: ch341: add I2C MFD cell driver for the CH341
2022-06-16 1:37 [PATCH v6 0/4] add driver for the WCH CH341 in I2C/GPIO mode frank zago
2022-06-16 1:37 ` [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode frank zago
2022-06-16 1:37 ` [PATCH v6 2/4] gpio: ch341: add GPIO MFD cell driver for the CH341 frank zago
@ 2022-06-16 1:37 ` frank zago
2022-06-16 5:09 ` Randy Dunlap
` (2 more replies)
2022-06-16 1:37 ` [PATCH v6 4/4] docs: misc: add documentation for ch341 driver frank zago
2022-06-20 10:08 ` [PATCH v6 0/4] add driver for the WCH CH341 in I2C/GPIO mode Johan Hovold
4 siblings, 3 replies; 18+ messages in thread
From: frank zago @ 2022-06-16 1:37 UTC (permalink / raw)
To: Greg Kroah-Hartman, linux-kernel, Bartosz Golaszewski,
Wolfram Sang, Johan Hovold, linux-usb, Lee Jones, Linus Walleij,
linux-gpio, linux-i2c, frank zago
The I2C interface can run at 4 different speeds. This driver currently
only offer 100kHz. Tested with a variety of I2C sensors, and the IIO
subsystem.
Signed-off-by: frank zago <frank@zago.net>
---
MAINTAINERS | 1 +
drivers/i2c/busses/Kconfig | 10 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-ch341.c | 377 +++++++++++++++++++++++++++++++++
4 files changed, 389 insertions(+)
create mode 100644 drivers/i2c/busses/i2c-ch341.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 8b93f6192704..837065fd3150 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -21480,6 +21480,7 @@ M: Frank Zago <frank@zago.net>
L: linux-usb@vger.kernel.org
S: Maintained
F: drivers/gpio/gpio-ch341.c
+F: drivers/i2c/busses/i2c-ch341.c
F: drivers/mfd/ch341-core.c
F: include/linux/mfd/ch341.h
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index a1bae59208e3..db9797345ad5 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -1199,6 +1199,16 @@ config I2C_RCAR
comment "External I2C/SMBus adapter drivers"
+config I2C_CH341
+ tristate "CH341 USB to I2C support"
+ select MFD_CH341
+ help
+ If you say yes to this option, I2C support will be included for the
+ WCH CH341, a USB to I2C/SPI/GPIO interface.
+
+ This driver can also be built as a module. If so, the module
+ will be called i2c-ch341.
+
config I2C_DIOLAN_U2C
tristate "Diolan U2C-12 USB adapter"
depends on USB
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 479f60e4ee3d..e83ca4a472f2 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -127,6 +127,7 @@ obj-$(CONFIG_I2C_XLP9XX) += i2c-xlp9xx.o
obj-$(CONFIG_I2C_RCAR) += i2c-rcar.o
# External I2C/SMBus adapter drivers
+obj-$(CONFIG_I2C_CH341) += i2c-ch341.o
obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o
obj-$(CONFIG_I2C_DLN2) += i2c-dln2.o
obj-$(CONFIG_I2C_CP2615) += i2c-cp2615.o
diff --git a/drivers/i2c/busses/i2c-ch341.c b/drivers/i2c/busses/i2c-ch341.c
new file mode 100644
index 000000000000..60c587cca4eb
--- /dev/null
+++ b/drivers/i2c/busses/i2c-ch341.c
@@ -0,0 +1,377 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * I2C cell driver for the CH341A, CH341B and CH341T.
+ *
+ * Copyright 2022, Frank Zago
+ * Copyright (c) 2016 Tse Lun Bien
+ * Copyright (c) 2014 Marco Gittler
+ * Copyright (C) 2006-2007 Till Harbaum (Till@Harbaum.org)
+ */
+
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/mfd/ch341.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/types.h>
+#include <linux/usb.h>
+
+/* I2C bus speed. Speed selection is not implemented. */
+#define CH341_I2C_20KHZ 0
+#define CH341_I2C_100KHZ 1
+#define CH341_I2C_400KHZ 2
+#define CH341_I2C_750KHZ 3
+
+/* I2C chip commands */
+#define CH341_CMD_I2C_STREAM 0xAA
+#define CH341_CMD_I2C_STM_END 0x00
+
+#define CH341_CMD_I2C_STM_STA 0x74
+#define CH341_CMD_I2C_STM_STO 0x75
+#define CH341_CMD_I2C_STM_OUT 0x80
+#define CH341_CMD_I2C_STM_IN 0xC0
+#define CH341_CMD_I2C_STM_SET 0x60
+
+/*
+ * The maximum request size is 4096 bytes, both for reading and
+ * writing, split in up to 128 32-byte segments, which includes the
+ * CH341 commands and the I2C data.
+ */
+#define SEG_COUNT 128
+
+/*
+ * Limit the transfer size that can be written. 4KiB is the maximum
+ * size of the whole buffer, but it must include all the command
+ * delimiters. 3KiB sounds reasonable.
+ */
+#define MAX_RW_LENGTH 3072
+
+struct ch341_i2c {
+ struct i2c_adapter adapter;
+
+ /* I2C request and response state */
+ int idx_out; /* current offset in buf */
+ int out_seg; /* current segment */
+ u8 i2c_buf[SEG_COUNT * SEG_SIZE];
+};
+
+/*
+ * Special case the no data transfer (SMBUS quick message), since some
+ * parameters are a bit different than the normal case.
+ */
+static int no_data_xfer(struct i2c_adapter *adapter, const struct i2c_msg *msg)
+{
+ struct ch341_i2c *dev = i2c_get_adapdata(adapter);
+ struct ch341_ddata *ddata = adapter->algo_data;
+ u8 *out = dev->i2c_buf;
+ int actual;
+ int ret;
+
+ out[0] = CH341_CMD_I2C_STREAM;
+ out[1] = CH341_CMD_I2C_STM_STA;
+ out[2] = CH341_CMD_I2C_STM_OUT;
+ out[3] = msg->addr << 1 | (msg->flags & I2C_M_RD);
+ out[4] = CH341_CMD_I2C_STM_IN;
+ out[5] = CH341_CMD_I2C_STM_STO;
+ out[6] = CH341_CMD_I2C_STM_END;
+
+ mutex_lock(&ddata->usb_lock);
+
+ /* Issue the request */
+ ret = usb_bulk_msg(ddata->usb_dev,
+ usb_sndbulkpipe(ddata->usb_dev, ddata->ep_out),
+ dev->i2c_buf, 7, &actual, DEFAULT_TIMEOUT_MS);
+ if (ret < 0) {
+ mutex_unlock(&ddata->usb_lock);
+ return ret;
+ }
+
+ ret = usb_bulk_msg(ddata->usb_dev,
+ usb_rcvbulkpipe(ddata->usb_dev, ddata->ep_in),
+ dev->i2c_buf, 2, &actual,
+ DEFAULT_TIMEOUT_MS);
+ if (ret < 0) {
+ mutex_unlock(&ddata->usb_lock);
+ return ret;
+ }
+
+ mutex_unlock(&ddata->usb_lock);
+
+ if (actual != 2 || dev->i2c_buf[0] & 0x80)
+ return -ETIMEDOUT;
+
+ return 1;
+}
+
+/*
+ * Append a write command to the current request. A set of 32-byte
+ * packets is filled. Each packet starts with STREAM and finishes with
+ * END, and contains an OUT field, leaving up to 29 bytes of data. The
+ * first packet must also include a START and the device address.
+ */
+static int append_write(struct ch341_i2c *dev, const struct i2c_msg *msg)
+{
+ bool start_done = false;
+ u8 *out = dev->i2c_buf;
+ int len;
+ u8 *p;
+
+ len = msg->len;
+ p = msg->buf;
+
+ while (len) {
+ int to_write;
+ int avail;
+
+ if (dev->idx_out % SEG_SIZE) {
+ /* Finish current packet, and advance to the next one */
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_END;
+ dev->out_seg++;
+ dev->idx_out = dev->out_seg * SEG_SIZE;
+
+ if (dev->out_seg == SEG_COUNT)
+ return -E2BIG;
+ }
+
+ out[dev->idx_out++] = CH341_CMD_I2C_STREAM;
+
+ /* account for stream start and end */
+ avail = SEG_SIZE - 3;
+
+ if (!start_done) {
+ /* Each message has a start */
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_STA;
+
+ avail -= 2; /* room for STA and device address */
+ }
+
+ to_write = min_t(int, len, avail);
+
+ if (!start_done) {
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_OUT | (to_write + 1);
+ out[dev->idx_out++] = msg->addr << 1;
+
+ start_done = true;
+ } else {
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_OUT | to_write;
+ }
+
+ memcpy(&out[dev->idx_out], p, to_write);
+ dev->idx_out += to_write;
+ len -= to_write;
+ p += to_write;
+ }
+
+ return 0;
+}
+
+/*
+ * Append a read command to the request. It usually follows a write
+ * command. When that happens, the driver will attempt to concat the
+ * read command into the same packet. Each read command, of up to 32
+ * bytes, must be written to a new packet. It is not possible to
+ * concat them.
+ */
+static int append_read(struct ch341_i2c *dev, const struct i2c_msg *msg)
+{
+ bool start_done = false;
+ u8 *out = dev->i2c_buf;
+ int len;
+
+ len = msg->len;
+
+ while (len) {
+ int to_read;
+
+ if (dev->idx_out % SEG_SIZE) {
+ if (!start_done &&
+ (dev->idx_out % SEG_SIZE) < (SEG_SIZE - 7)) {
+ /* There's enough left for a read */
+ } else {
+ /* Finish current packet, and advance to the next one */
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_END;
+ dev->out_seg++;
+ dev->idx_out = dev->out_seg * SEG_SIZE;
+
+ if (dev->out_seg == SEG_COUNT)
+ return -E2BIG;
+
+ out[dev->idx_out++] = CH341_CMD_I2C_STREAM;
+ }
+ } else {
+ out[dev->idx_out++] = CH341_CMD_I2C_STREAM;
+ }
+
+ if (!start_done) {
+ /* Each message has a start */
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_STA;
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_OUT | 1;
+ out[dev->idx_out++] = msg->addr << 1 | 1;
+
+ start_done = true;
+ }
+
+ /* Apparently the last command must be an STM_IN to
+ * read the last byte. Without it, the adapter gets
+ * lost.
+ */
+ to_read = min_t(int, len, 32);
+ len -= to_read;
+ if (len == 0) {
+ if (to_read > 1)
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_IN | (to_read - 1);
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_IN;
+ } else {
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_IN | to_read;
+ }
+ }
+
+ return 0;
+}
+
+static int ch341_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num)
+{
+ struct ch341_i2c *dev = i2c_get_adapdata(adapter);
+ struct ch341_ddata *ddata = adapter->algo_data;
+ u8 *out = dev->i2c_buf;
+ int actual;
+ int ret;
+ int i;
+
+ /* Special case */
+ if (num == 1 && msgs[0].len == 0)
+ return no_data_xfer(adapter, &msgs[0]);
+
+ /* Prepare the request */
+ dev->idx_out = 0;
+ dev->out_seg = 0;
+
+ for (i = 0; i != num; i++) {
+ if (msgs[i].flags & I2C_M_RD)
+ ret = append_read(dev, &msgs[i]);
+ else
+ ret = append_write(dev, &msgs[i]);
+
+ if (ret)
+ return ret;
+ }
+
+ /* Finish the last packet */
+ if (SEG_SIZE - (dev->idx_out % SEG_SIZE) < 2) {
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_END;
+
+ dev->out_seg++;
+ if (dev->out_seg == SEG_COUNT)
+ return -E2BIG;
+
+ dev->idx_out = dev->out_seg * SEG_SIZE;
+
+ out[dev->idx_out++] = CH341_CMD_I2C_STREAM;
+ }
+
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_STO;
+ out[dev->idx_out++] = CH341_CMD_I2C_STM_END;
+
+ mutex_lock(&ddata->usb_lock);
+
+ /* Issue the request */
+ ret = usb_bulk_msg(ddata->usb_dev,
+ usb_sndbulkpipe(ddata->usb_dev, ddata->ep_out),
+ dev->i2c_buf, dev->idx_out, &actual, DEFAULT_TIMEOUT_MS);
+ if (ret < 0) {
+ mutex_unlock(&ddata->usb_lock);
+ return ret;
+ }
+
+ for (i = 0; i != num; i++) {
+ if (!(msgs[i].flags & I2C_M_RD))
+ continue;
+
+ ret = usb_bulk_msg(ddata->usb_dev,
+ usb_rcvbulkpipe(ddata->usb_dev, ddata->ep_in),
+ dev->i2c_buf, msgs[i].len, &actual,
+ DEFAULT_TIMEOUT_MS);
+
+ if (ret) {
+ mutex_unlock(&ddata->usb_lock);
+ return ret;
+ }
+
+ if (actual != msgs[i].len) {
+ mutex_unlock(&ddata->usb_lock);
+ return -EIO;
+ }
+
+ memcpy(msgs[i].buf, dev->i2c_buf, actual);
+ }
+
+ mutex_unlock(&ddata->usb_lock);
+
+ return num;
+}
+
+static u32 ch341_i2c_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm ch341_i2c_algorithm = {
+ .master_xfer = ch341_i2c_xfer,
+ .functionality = ch341_i2c_func,
+};
+
+static const struct i2c_adapter_quirks ch341_i2c_quirks = {
+ .max_read_len = MAX_RW_LENGTH,
+ .max_write_len = MAX_RW_LENGTH,
+};
+
+static int ch341_i2c_probe(struct platform_device *pdev)
+{
+ struct ch341_ddata *ddata = dev_get_drvdata(pdev->dev.parent);
+ struct ch341_i2c *ch341_i2c;
+ int actual;
+ int ret;
+
+ ch341_i2c = devm_kzalloc(&pdev->dev, sizeof(*ch341_i2c), GFP_KERNEL);
+ if (ch341_i2c == NULL)
+ return -ENOMEM;
+
+ ch341_i2c->adapter.owner = THIS_MODULE;
+ ch341_i2c->adapter.class = I2C_CLASS_HWMON;
+ ch341_i2c->adapter.algo = &ch341_i2c_algorithm;
+ ch341_i2c->adapter.algo_data = ddata;
+ ch341_i2c->adapter.quirks = &ch341_i2c_quirks;
+ ch341_i2c->adapter.dev.parent = &pdev->dev;
+ snprintf(ch341_i2c->adapter.name, sizeof(ch341_i2c->adapter.name),
+ "CH341 I2C USB bus %03d device %03d",
+ ddata->usb_dev->bus->busnum, ddata->usb_dev->devnum);
+
+ i2c_set_adapdata(&ch341_i2c->adapter, ch341_i2c);
+ platform_set_drvdata(pdev, ch341_i2c);
+
+ /* Set ch341 i2c speed */
+ ch341_i2c->i2c_buf[0] = CH341_CMD_I2C_STREAM;
+ ch341_i2c->i2c_buf[1] = CH341_CMD_I2C_STM_SET | CH341_I2C_100KHZ;
+ ch341_i2c->i2c_buf[2] = CH341_CMD_I2C_STM_END;
+ mutex_lock(&ddata->usb_lock);
+ ret = usb_bulk_msg(ddata->usb_dev,
+ usb_sndbulkpipe(ddata->usb_dev, ddata->ep_out),
+ ch341_i2c->i2c_buf, 3, &actual, DEFAULT_TIMEOUT_MS);
+ mutex_unlock(&ddata->usb_lock);
+
+ if (ret < 0)
+ return dev_err_probe(&pdev->dev, ret, "Cannot set I2C speed\n");
+
+ return devm_i2c_add_adapter(&pdev->dev, &ch341_i2c->adapter);
+}
+
+static struct platform_driver ch341_i2c_driver = {
+ .driver.name = "ch341-i2c",
+ .probe = ch341_i2c_probe,
+};
+module_platform_driver(ch341_i2c_driver);
+
+MODULE_AUTHOR("Frank Zago <frank@zago.net>");
+MODULE_DESCRIPTION("CH341 USB to I2C");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ch341-i2c");
--
2.32.0
^ permalink raw reply related [flat|nested] 18+ messages in thread
* [PATCH v6 4/4] docs: misc: add documentation for ch341 driver
2022-06-16 1:37 [PATCH v6 0/4] add driver for the WCH CH341 in I2C/GPIO mode frank zago
` (2 preceding siblings ...)
2022-06-16 1:37 ` [PATCH v6 3/4] i2c: ch341: add I2C " frank zago
@ 2022-06-16 1:37 ` frank zago
2022-06-20 10:08 ` [PATCH v6 0/4] add driver for the WCH CH341 in I2C/GPIO mode Johan Hovold
4 siblings, 0 replies; 18+ messages in thread
From: frank zago @ 2022-06-16 1:37 UTC (permalink / raw)
To: Greg Kroah-Hartman, linux-kernel, Bartosz Golaszewski,
Wolfram Sang, Johan Hovold, linux-usb, Lee Jones, Linus Walleij,
linux-gpio, linux-i2c, frank zago
Document the multifunction CH341 chip driver, in GPIO and I2C mode.
Signed-off-by: frank zago <frank@zago.net>
---
Documentation/misc-devices/ch341.rst | 109 +++++++++++++++++++++++++++
Documentation/misc-devices/index.rst | 1 +
2 files changed, 110 insertions(+)
create mode 100644 Documentation/misc-devices/ch341.rst
diff --git a/Documentation/misc-devices/ch341.rst b/Documentation/misc-devices/ch341.rst
new file mode 100644
index 000000000000..65ba293bdc2d
--- /dev/null
+++ b/Documentation/misc-devices/ch341.rst
@@ -0,0 +1,109 @@
+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+===========================================================
+WinChipHead (沁恒) CH341 linux driver for I2C and GPIO mode
+===========================================================
+
+The CH341 is declined in several flavors, and may support one or more
+of UART, SPI, I2C and GPIO, but not always simultaneously:
+
+ - CH341 A/B/F: UART, Printer, SPI, I2C and GPIO
+ - CH341 C/T: UART and I2C
+ - CH341 H: SPI
+
+They work in 3 different modes, with only one being presented
+depending on the USB PID:
+
+ - 0x5523: UART mode, covered by the USB `ch341` serial driver
+ - 0x5512: SPI/I2C/GPIO mode, covered by the ch341 MFD drivers
+ - 0x5584: Parallel printer mode, covered by the USB `usblp` driver
+
+Mode selection is done at the hardware level by tying some
+pins. Breakout boards with one of the CH341 chip usually have one or
+more jumpers to select which mode they work on. At least one model
+(CJMCU-341) appears to need bridging some solder pads to select a
+different default. Breakout boards also don't usually offer an option
+to configure the chip into printer mode; for that case, connect the
+SCL and SDA lines directly together.
+
+The various CH341 appear to be indistinguishable from the
+software. For instance the ch341 MFD driver will present a GPIO
+interface for the CH341T although physical pins are not present, and
+the device will accept GPIO commands.
+
+The ch341 MFD driver has been tested with a CH341A, CH341B and
+CH341T.
+
+Some breakout boards work in 3.3V and 5V depending on some jumpers.
+
+The black chip programmer with a ZIF socket will power the CH341 at
+3.3V if a jumper is set, but will only output 5V to the chips to be
+programmed, which is not always desirable. A hardware hack to use 3.3V
+everywhere, involving some soldering, is available at
+https://eevblog.com/forum/repair/ch341a-serial-memory-programmer-power-supply-fix/
+
+Some sample code for the CH341 is available at the manufacturer
+website, at http://wch-ic.com/products/CH341.html
+
+The repository at https://github.com/boseji/CH341-Store contains a lot
+of information on these chips, including datasheets.
+
+This driver is based on the pre-existing work at
+https://github.com/gschorcht/i2c-ch341-usb
+
+
+I2C Caveats
+-----------
+
+The ch341 doesn't work with a Wii nunchuk, possibly because the
+pull-up value is too low (1500 ohms).
+
+i2c AT24 eeproms can be read but not programmed properly because the
+at24 linux driver tries to write a byte at a time, and doesn't wait at
+all (or enough) between writes. Data corruption on writes does occur.
+
+
+The GPIOs
+---------
+
+16 GPIOs are available on the CH341 A/B/F. The first 6 are input/output,
+and the last 10 are input only.
+
+Pinout and their names as they appear on some breakout boards::
+
+ CH341A/B/F GPIO Names Mode
+ pin line
+
+ 15 0 D0, CS0 input/output
+ 16 1 D1, CS1 input/output
+ 17 2 D2, CS2 input/output
+ 18 3 D3, SCK, DCK input/output
+ 19 4 D4, DOUT2, CS3 input/output
+ 20 5 D5, MOSI, DOUT, SDO input/output
+ 21 6 D6, DIN2 input
+ 22 7 D7, MISO, DIN input
+ 5 8 ERR input
+ 6 9 PEMP input
+ 7 10 INT input
+ 8 11 SLCT (SELECT) input
+ 26 12 RST# (?) input
+ 27 13 WT (WAIT) input
+ 4 14 DS (Data Select?) input
+ 3 15 AS (Address Select?) input
+
+
+GPIO interrupt
+~~~~~~~~~~~~~~
+
+The INT pin, corresponding to GPIO 10 is an input pin that can trigger
+an interrupt on a rising edge. Only that pin is able to generate an
+interrupt, and only on a rising edge. Trying to monitor events on
+another GPIO, or that GPIO on something other than a rising edge, will
+be rejected.
+
+
+SPI
+---
+
+This driver doesn't offer an SPI interface (yet) due to the
+impossibility of declaring an SPI device like I2C does.
diff --git a/Documentation/misc-devices/index.rst b/Documentation/misc-devices/index.rst
index 756be15a49a4..e85531a4f354 100644
--- a/Documentation/misc-devices/index.rst
+++ b/Documentation/misc-devices/index.rst
@@ -19,6 +19,7 @@ fit into other categories.
bh1770glc
eeprom
c2port
+ ch341
dw-xdata-pcie
ibmvmc
ics932s401
--
2.32.0
^ permalink raw reply related [flat|nested] 18+ messages in thread
* Re: [PATCH v6 3/4] i2c: ch341: add I2C MFD cell driver for the CH341
2022-06-16 1:37 ` [PATCH v6 3/4] i2c: ch341: add I2C " frank zago
@ 2022-06-16 5:09 ` Randy Dunlap
2022-06-16 9:18 ` kernel test robot
2022-06-16 11:10 ` kernel test robot
2 siblings, 0 replies; 18+ messages in thread
From: Randy Dunlap @ 2022-06-16 5:09 UTC (permalink / raw)
To: frank zago, Greg Kroah-Hartman, linux-kernel,
Bartosz Golaszewski, Wolfram Sang, Johan Hovold, linux-usb,
Lee Jones, Linus Walleij, linux-gpio, linux-i2c
Hi--
On 6/15/22 18:37, frank zago wrote:
> The I2C interface can run at 4 different speeds. This driver currently
> only offer 100kHz. Tested with a variety of I2C sensors, and the IIO
> subsystem.
>
> Signed-off-by: frank zago <frank@zago.net>
> ---
> MAINTAINERS | 1 +
> drivers/i2c/busses/Kconfig | 10 +
> drivers/i2c/busses/Makefile | 1 +
> drivers/i2c/busses/i2c-ch341.c | 377 +++++++++++++++++++++++++++++++++
> 4 files changed, 389 insertions(+)
> create mode 100644 drivers/i2c/busses/i2c-ch341.c
>
> diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
> index a1bae59208e3..db9797345ad5 100644
> --- a/drivers/i2c/busses/Kconfig
> +++ b/drivers/i2c/busses/Kconfig
> @@ -1199,6 +1199,16 @@ config I2C_RCAR
>
> comment "External I2C/SMBus adapter drivers"
>
> +config I2C_CH341
> + tristate "CH341 USB to I2C support"
> + select MFD_CH341
> + help
> + If you say yes to this option, I2C support will be included for the
> + WCH CH341, a USB to I2C/SPI/GPIO interface.
> +
> + This driver can also be built as a module. If so, the module
> + will be called i2c-ch341.
I haven't tested it, but just from reading, it looks like
this one needs a "depends on USB" since it selects MFD_CH341, which
depends on USB, and since 'select' ignores dependency chains.
The GPIO driver (patch 2/4) already depends on USB.
--
~Randy
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 3/4] i2c: ch341: add I2C MFD cell driver for the CH341
2022-06-16 1:37 ` [PATCH v6 3/4] i2c: ch341: add I2C " frank zago
2022-06-16 5:09 ` Randy Dunlap
@ 2022-06-16 9:18 ` kernel test robot
2022-06-16 11:10 ` kernel test robot
2 siblings, 0 replies; 18+ messages in thread
From: kernel test robot @ 2022-06-16 9:18 UTC (permalink / raw)
To: frank zago, Greg Kroah-Hartman, linux-kernel,
Bartosz Golaszewski, Wolfram Sang, Johan Hovold, linux-usb,
Lee Jones, Linus Walleij, linux-gpio, linux-i2c
Cc: kbuild-all
Hi frank,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on lee-mfd/for-mfd-next]
[also build test ERROR on brgl/gpio/for-next wsa/i2c/for-next linus/master v5.19-rc2 next-20220615]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/frank-zago/add-driver-for-the-WCH-CH341-in-I2C-GPIO-mode/20220616-094113
base: https://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd.git for-mfd-next
config: nios2-randconfig-r026-20220616 (https://download.01.org/0day-ci/archive/20220616/202206161751.5icAiwNf-lkp@intel.com/config)
compiler: nios2-linux-gcc (GCC) 11.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/46c68aee86d34ee630272146a73ad7c3147bb094
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review frank-zago/add-driver-for-the-WCH-CH341-in-I2C-GPIO-mode/20220616-094113
git checkout 46c68aee86d34ee630272146a73ad7c3147bb094
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross W=1 O=build_dir ARCH=nios2 SHELL=/bin/bash
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>):
nios2-linux-ld: drivers/mfd/ch341-core.o: in function `ch341_usb_probe':
>> drivers/mfd/ch341-core.c:46: undefined reference to `usb_find_common_endpoints'
drivers/mfd/ch341-core.c:46:(.text+0x8c): relocation truncated to fit: R_NIOS2_CALL26 against `usb_find_common_endpoints'
nios2-linux-ld: drivers/mfd/ch341-core.o: in function `ch341_usb_driver_init':
>> drivers/mfd/ch341-core.c:86: undefined reference to `usb_register_driver'
drivers/mfd/ch341-core.c:86:(.init.text+0x1c): relocation truncated to fit: R_NIOS2_CALL26 against `usb_register_driver'
nios2-linux-ld: drivers/i2c/busses/i2c-ch341.o: in function `no_data_xfer':
>> drivers/i2c/busses/i2c-ch341.c:81: undefined reference to `usb_bulk_msg'
drivers/i2c/busses/i2c-ch341.c:81:(.text+0xe0): relocation truncated to fit: R_NIOS2_CALL26 against `usb_bulk_msg'
>> nios2-linux-ld: drivers/i2c/busses/i2c-ch341.c:89: undefined reference to `usb_bulk_msg'
drivers/i2c/busses/i2c-ch341.c:89:(.text+0x134): relocation truncated to fit: R_NIOS2_CALL26 against `usb_bulk_msg'
nios2-linux-ld: drivers/i2c/busses/i2c-ch341.o: in function `ch341_i2c_xfer':
drivers/i2c/busses/i2c-ch341.c:278: undefined reference to `usb_bulk_msg'
drivers/i2c/busses/i2c-ch341.c:278:(.text+0x4e0): relocation truncated to fit: R_NIOS2_CALL26 against `usb_bulk_msg'
nios2-linux-ld: drivers/i2c/busses/i2c-ch341.c:290: undefined reference to `usb_bulk_msg'
drivers/i2c/busses/i2c-ch341.c:290:(.text+0x558): relocation truncated to fit: R_NIOS2_CALL26 against `usb_bulk_msg'
nios2-linux-ld: drivers/i2c/busses/i2c-ch341.o: in function `ch341_i2c_probe':
drivers/i2c/busses/i2c-ch341.c:357: undefined reference to `usb_bulk_msg'
drivers/i2c/busses/i2c-ch341.c:357:(.text+0x778): relocation truncated to fit: R_NIOS2_CALL26 against `usb_bulk_msg'
pahole: .tmp_vmlinux.btf: No such file or directory
.btf.vmlinux.bin.o: file not recognized: file format not recognized
Kconfig warnings: (for reference only)
WARNING: unmet direct dependencies detected for MFD_CH341
Depends on HAS_IOMEM && USB
Selected by
- I2C_CH341 && I2C && HAS_IOMEM
vim +46 drivers/mfd/ch341-core.c
f33ee28d4d85a8 frank zago 2022-06-15 29
f33ee28d4d85a8 frank zago 2022-06-15 30 static int ch341_usb_probe(struct usb_interface *iface,
f33ee28d4d85a8 frank zago 2022-06-15 31 const struct usb_device_id *usb_id)
f33ee28d4d85a8 frank zago 2022-06-15 32 {
f33ee28d4d85a8 frank zago 2022-06-15 33 struct usb_endpoint_descriptor *bulk_out;
f33ee28d4d85a8 frank zago 2022-06-15 34 struct usb_endpoint_descriptor *bulk_in;
f33ee28d4d85a8 frank zago 2022-06-15 35 struct usb_endpoint_descriptor *intr_in;
f33ee28d4d85a8 frank zago 2022-06-15 36 struct ch341_ddata *ddata;
f33ee28d4d85a8 frank zago 2022-06-15 37 int ret;
f33ee28d4d85a8 frank zago 2022-06-15 38
f33ee28d4d85a8 frank zago 2022-06-15 39 ddata = devm_kzalloc(&iface->dev, sizeof(*ddata), GFP_KERNEL);
f33ee28d4d85a8 frank zago 2022-06-15 40 if (!ddata)
f33ee28d4d85a8 frank zago 2022-06-15 41 return -ENOMEM;
f33ee28d4d85a8 frank zago 2022-06-15 42
f33ee28d4d85a8 frank zago 2022-06-15 43 ddata->usb_dev = interface_to_usbdev(iface);
f33ee28d4d85a8 frank zago 2022-06-15 44 mutex_init(&ddata->usb_lock);
f33ee28d4d85a8 frank zago 2022-06-15 45
f33ee28d4d85a8 frank zago 2022-06-15 @46 ret = usb_find_common_endpoints(iface->cur_altsetting, &bulk_in,
f33ee28d4d85a8 frank zago 2022-06-15 47 &bulk_out, &intr_in, NULL);
f33ee28d4d85a8 frank zago 2022-06-15 48 if (ret) {
f33ee28d4d85a8 frank zago 2022-06-15 49 dev_err(&iface->dev, "Could not find all endpoints\n");
f33ee28d4d85a8 frank zago 2022-06-15 50 return -ENODEV;
f33ee28d4d85a8 frank zago 2022-06-15 51 }
f33ee28d4d85a8 frank zago 2022-06-15 52
f33ee28d4d85a8 frank zago 2022-06-15 53 ddata->ep_in = bulk_in->bEndpointAddress;
f33ee28d4d85a8 frank zago 2022-06-15 54 ddata->ep_out = bulk_out->bEndpointAddress;
f33ee28d4d85a8 frank zago 2022-06-15 55 ddata->ep_intr = intr_in->bEndpointAddress;
f33ee28d4d85a8 frank zago 2022-06-15 56 ddata->ep_intr_interval = intr_in->bInterval;
f33ee28d4d85a8 frank zago 2022-06-15 57
f33ee28d4d85a8 frank zago 2022-06-15 58 usb_set_intfdata(iface, ddata);
f33ee28d4d85a8 frank zago 2022-06-15 59
f33ee28d4d85a8 frank zago 2022-06-15 60 ret = mfd_add_devices(&iface->dev, PLATFORM_DEVID_AUTO, ch341_devs,
f33ee28d4d85a8 frank zago 2022-06-15 61 ARRAY_SIZE(ch341_devs), NULL, 0, NULL);
f33ee28d4d85a8 frank zago 2022-06-15 62 if (ret)
f33ee28d4d85a8 frank zago 2022-06-15 63 return dev_err_probe(&iface->dev, ret,
f33ee28d4d85a8 frank zago 2022-06-15 64 "Failed to register child devices\n");
f33ee28d4d85a8 frank zago 2022-06-15 65
f33ee28d4d85a8 frank zago 2022-06-15 66 return 0;
f33ee28d4d85a8 frank zago 2022-06-15 67 }
f33ee28d4d85a8 frank zago 2022-06-15 68
f33ee28d4d85a8 frank zago 2022-06-15 69 static void ch341_usb_disconnect(struct usb_interface *usb_if)
f33ee28d4d85a8 frank zago 2022-06-15 70 {
f33ee28d4d85a8 frank zago 2022-06-15 71 mfd_remove_devices(&usb_if->dev);
f33ee28d4d85a8 frank zago 2022-06-15 72 }
f33ee28d4d85a8 frank zago 2022-06-15 73
f33ee28d4d85a8 frank zago 2022-06-15 74 static const struct usb_device_id ch341_usb_table[] = {
f33ee28d4d85a8 frank zago 2022-06-15 75 { USB_DEVICE(0x1a86, 0x5512) },
f33ee28d4d85a8 frank zago 2022-06-15 76 { }
f33ee28d4d85a8 frank zago 2022-06-15 77 };
f33ee28d4d85a8 frank zago 2022-06-15 78 MODULE_DEVICE_TABLE(usb, ch341_usb_table);
f33ee28d4d85a8 frank zago 2022-06-15 79
f33ee28d4d85a8 frank zago 2022-06-15 80 static struct usb_driver ch341_usb_driver = {
f33ee28d4d85a8 frank zago 2022-06-15 81 .name = "ch341-mfd",
f33ee28d4d85a8 frank zago 2022-06-15 82 .id_table = ch341_usb_table,
f33ee28d4d85a8 frank zago 2022-06-15 83 .probe = ch341_usb_probe,
f33ee28d4d85a8 frank zago 2022-06-15 84 .disconnect = ch341_usb_disconnect,
f33ee28d4d85a8 frank zago 2022-06-15 85 };
f33ee28d4d85a8 frank zago 2022-06-15 @86 module_usb_driver(ch341_usb_driver);
f33ee28d4d85a8 frank zago 2022-06-15 87
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 3/4] i2c: ch341: add I2C MFD cell driver for the CH341
2022-06-16 1:37 ` [PATCH v6 3/4] i2c: ch341: add I2C " frank zago
2022-06-16 5:09 ` Randy Dunlap
2022-06-16 9:18 ` kernel test robot
@ 2022-06-16 11:10 ` kernel test robot
2 siblings, 0 replies; 18+ messages in thread
From: kernel test robot @ 2022-06-16 11:10 UTC (permalink / raw)
To: frank zago, Greg Kroah-Hartman, linux-kernel,
Bartosz Golaszewski, Wolfram Sang, Johan Hovold, linux-usb,
Lee Jones, Linus Walleij, linux-gpio, linux-i2c
Cc: kbuild-all
Hi frank,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on lee-mfd/for-mfd-next]
[also build test ERROR on brgl/gpio/for-next wsa/i2c/for-next linus/master v5.19-rc2 next-20220616]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]
url: https://github.com/intel-lab-lkp/linux/commits/frank-zago/add-driver-for-the-WCH-CH341-in-I2C-GPIO-mode/20220616-094113
base: https://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd.git for-mfd-next
config: arc-buildonly-randconfig-r004-20220616 (https://download.01.org/0day-ci/archive/20220616/202206161938.BiOHSAOi-lkp@intel.com/config)
compiler: arc-elf-gcc (GCC) 11.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/46c68aee86d34ee630272146a73ad7c3147bb094
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review frank-zago/add-driver-for-the-WCH-CH341-in-I2C-GPIO-mode/20220616-094113
git checkout 46c68aee86d34ee630272146a73ad7c3147bb094
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross W=1 O=build_dir ARCH=arc SHELL=/bin/bash
If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>
All errors (new ones prefixed by >>, old ones prefixed by <<):
>> ERROR: modpost: "usb_bulk_msg" [drivers/i2c/busses/i2c-ch341.ko] undefined!
>> ERROR: modpost: "usb_deregister" [drivers/mfd/ch341-core.ko] undefined!
>> ERROR: modpost: "usb_register_driver" [drivers/mfd/ch341-core.ko] undefined!
>> ERROR: modpost: "usb_find_common_endpoints" [drivers/mfd/ch341-core.ko] undefined!
Kconfig warnings: (for reference only)
WARNING: unmet direct dependencies detected for MFD_CH341
Depends on HAS_IOMEM && USB
Selected by
- I2C_CH341 && I2C && HAS_IOMEM
--
0-DAY CI Kernel Test Service
https://01.org/lkp
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 2/4] gpio: ch341: add GPIO MFD cell driver for the CH341
2022-06-16 1:37 ` [PATCH v6 2/4] gpio: ch341: add GPIO MFD cell driver for the CH341 frank zago
@ 2022-06-17 8:29 ` Linus Walleij
2022-06-20 10:25 ` Johan Hovold
1 sibling, 0 replies; 18+ messages in thread
From: Linus Walleij @ 2022-06-17 8:29 UTC (permalink / raw)
To: frank zago
Cc: Greg Kroah-Hartman, linux-kernel, Bartosz Golaszewski,
Wolfram Sang, Johan Hovold, linux-usb, Lee Jones, linux-gpio,
linux-i2c
On Thu, Jun 16, 2022 at 3:38 AM frank zago <frank@zago.net> wrote:
> The GPIO interface offers 16 GPIOs. 6 are read/write, and 10 are
> read-only.
>
> Signed-off-by: frank zago <frank@zago.net>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Please preserve my ACK on subsequent postings, USB changes does
not concern me, I trust Johan to review those for you.
Yours,
Linus Walleij
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 0/4] add driver for the WCH CH341 in I2C/GPIO mode
2022-06-16 1:37 [PATCH v6 0/4] add driver for the WCH CH341 in I2C/GPIO mode frank zago
` (3 preceding siblings ...)
2022-06-16 1:37 ` [PATCH v6 4/4] docs: misc: add documentation for ch341 driver frank zago
@ 2022-06-20 10:08 ` Johan Hovold
4 siblings, 0 replies; 18+ messages in thread
From: Johan Hovold @ 2022-06-20 10:08 UTC (permalink / raw)
To: frank zago
Cc: Greg Kroah-Hartman, linux-kernel, Bartosz Golaszewski,
Wolfram Sang, linux-usb, Lee Jones, Linus Walleij, linux-gpio,
linux-i2c
On Wed, Jun 15, 2022 at 08:37:43PM -0500, frank zago wrote:
> 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.
>
> Changes from v5:
> Addressed reviewers' comments.
Please be more specific in your changelogs. This essentially just says
"changed stuff".
> Better handling of 0-bytes i2c commands
> Use of better USB API.
What does this even mean?
Johan
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 2/4] gpio: ch341: add GPIO MFD cell driver for the CH341
2022-06-16 1:37 ` [PATCH v6 2/4] gpio: ch341: add GPIO MFD cell driver for the CH341 frank zago
2022-06-17 8:29 ` Linus Walleij
@ 2022-06-20 10:25 ` Johan Hovold
2022-06-20 16:08 ` Andy Shevchenko
1 sibling, 1 reply; 18+ messages in thread
From: Johan Hovold @ 2022-06-20 10:25 UTC (permalink / raw)
To: frank zago
Cc: Greg Kroah-Hartman, linux-kernel, Bartosz Golaszewski,
Wolfram Sang, linux-usb, Lee Jones, Linus Walleij, linux-gpio,
linux-i2c
On Wed, Jun 15, 2022 at 08:37:45PM -0500, frank zago wrote:
> The GPIO interface offers 16 GPIOs. 6 are read/write, and 10 are
> read-only.
Please mention the single interrupt line here too.
> Signed-off-by: frank zago <frank@zago.net>
> ---
> MAINTAINERS | 1 +
> drivers/gpio/Kconfig | 10 +
> drivers/gpio/Makefile | 1 +
> drivers/gpio/gpio-ch341.c | 385 ++++++++++++++++++++++++++++++++++++++
> include/linux/mfd/ch341.h | 8 +
> 5 files changed, 405 insertions(+)
> create mode 100644 drivers/gpio/gpio-ch341.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 628eeaa9bf68..8b93f6192704 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -21479,6 +21479,7 @@ WINCHIPHEAD CH341 I2C/GPIO MFD DRIVER
> M: Frank Zago <frank@zago.net>
> L: linux-usb@vger.kernel.org
> S: Maintained
> +F: drivers/gpio/gpio-ch341.c
> F: drivers/mfd/ch341-core.c
> F: include/linux/mfd/ch341.h
>
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index b01961999ced..473b6e7226ca 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -1653,6 +1653,16 @@ endmenu
> menu "USB GPIO expanders"
> depends on USB
>
> +config GPIO_CH341
> + tristate "CH341 USB to GPIO support"
> + select MFD_CH341
This should be "depends" (for all subdrivers).
> + help
> + If you say yes to this option, GPIO support will be included for the
> + WCH CH341, a USB to I2C/SPI/GPIO interface.
> +
> + This driver can also be built as a module. If so, the module
> + will be called gpio-ch341.
> +
> config GPIO_VIPERBOARD
> tristate "Viperboard GPIO a & b support"
> depends on MFD_VIPERBOARD
[ and other MFD drivers as you see here ]
> diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
> index 14352f6dfe8e..beef802cbfb1 100644
> --- a/drivers/gpio/Makefile
> +++ b/drivers/gpio/Makefile
> @@ -44,6 +44,7 @@ obj-$(CONFIG_GPIO_BD9571MWV) += gpio-bd9571mwv.o
> obj-$(CONFIG_GPIO_BRCMSTB) += gpio-brcmstb.o
> obj-$(CONFIG_GPIO_BT8XX) += gpio-bt8xx.o
> obj-$(CONFIG_GPIO_CADENCE) += gpio-cadence.o
> +obj-$(CONFIG_GPIO_CH341) += gpio-ch341.o
> obj-$(CONFIG_GPIO_CLPS711X) += gpio-clps711x.o
> obj-$(CONFIG_GPIO_SNPS_CREG) += gpio-creg-snps.o
> obj-$(CONFIG_GPIO_CRYSTAL_COVE) += gpio-crystalcove.o
> diff --git a/drivers/gpio/gpio-ch341.c b/drivers/gpio/gpio-ch341.c
> new file mode 100644
> index 000000000000..233dfe1f2ae8
> --- /dev/null
> +++ b/drivers/gpio/gpio-ch341.c
> @@ -0,0 +1,385 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * GPIO cell driver for the CH341A and CH341B chips.
> + *
> + * Copyright 2022, Frank Zago
How about using a unified format for these lines?
> + * Copyright (c) 2017 Gunar Schorcht (gunar@schorcht.net)
> + * Copyright (c) 2016 Tse Lun Bien
> + * Copyright (c) 2014 Marco Gittler
> + * Copyright (c) 2006-2007 Till Harbaum (Till@Harbaum.org)
> + */
> +
> +/*
> + * Notes.
> + *
> + * For the CH341, 0=IN, 1=OUT, but for the GPIO subsystem, 1=IN and
> + * 0=OUT. Translation happens in a couple places.
> + */
> +
> +#include <linux/gpio/driver.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/ch341.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/types.h>
> +#include <linux/usb.h>
> +
> +#define CH341_GPIO_NUM_PINS 16 /* Number of GPIO pins */
> +
> +/* GPIO chip commands */
> +#define CH341_PARA_CMD_STS 0xA0 /* Get pins status */
> +#define CH341_CMD_UIO_STREAM 0xAB /* pin IO stream command */
> +
> +#define CH341_CMD_UIO_STM_OUT 0x80 /* pin IO interface OUT command (D0~D5) */
> +#define CH341_CMD_UIO_STM_DIR 0x40 /* pin IO interface DIR command (D0~D5) */
> +#define CH341_CMD_UIO_STM_END 0x20 /* pin IO interface END command */
> +
> +#define CH341_USB_MAX_INTR_SIZE 8
> +
> +struct ch341_gpio {
> + struct gpio_chip gpio;
> + struct mutex gpio_lock;
> + u16 gpio_dir; /* 1 bit per pin, 0=IN, 1=OUT. */
> + u16 gpio_last_read; /* last GPIO values read */
> + u16 gpio_last_written; /* last GPIO values written */
> + union {
> + u8 gpio_buf[SEG_SIZE];
> + __le16 gpio_buf_status;
> + };
This one should be allocated separately from the containing structure
since it may be mapped for DMA.
> +
> + struct urb *irq_urb;
> + struct usb_anchor irq_urb_out;
> + u8 irq_buf[CH341_USB_MAX_INTR_SIZE];
Same here.
You may need to check other drivers too.
> + struct irq_chip irq_chip;
> +
> + struct ch341_ddata *ddata;
> +};
> +
> +/*
> + * Masks to describe the 16 GPIOs. Pins D0 to D5 (mapped to GPIOs 0 to
> + * 5) can do input/output, but the other pins are input-only.
> + */
> +static const u16 pin_can_output = 0b111111;
> +
> +/* Only GPIO 10 (INT# line) has hardware interrupt */
> +#define CH341_GPIO_INT_LINE 10
> +
> +/* Send a command and get a reply if requested */
> +static int gpio_transfer(struct ch341_gpio *dev, int out_len, int in_len)
> +{
> + struct ch341_ddata *ddata = dev->ddata;
> + int actual;
> + int ret;
> +
> + mutex_lock(&ddata->usb_lock);
> +
> + ret = usb_bulk_msg(ddata->usb_dev,
> + usb_sndbulkpipe(ddata->usb_dev, ddata->ep_out),
> + dev->gpio_buf, out_len,
> + &actual, DEFAULT_TIMEOUT_MS);
> + if (ret < 0)
> + goto out_unlock;
> +
> + if (in_len == 0)
> + goto out_unlock;
> +
> + ret = usb_bulk_msg(ddata->usb_dev,
> + usb_rcvbulkpipe(ddata->usb_dev, ddata->ep_in),
> + dev->gpio_buf, SEG_SIZE, &actual, DEFAULT_TIMEOUT_MS);
> +
> +out_unlock:
> + mutex_unlock(&ddata->usb_lock);
> +
> + if (ret < 0)
> + return ret;
> +
> + return actual;
> +}
> +static void ch341_complete_intr_urb(struct urb *urb)
> +{
> + struct ch341_gpio *dev = urb->context;
> + int ret;
> +
> + if (urb->status) {
> + usb_unanchor_urb(dev->irq_urb);
Again, why is this here?
> + } else {
> + /*
> + * Data is 8 bytes. Byte 0 might be the length of
> + * significant data, which is 3 more bytes. Bytes 1
> + * and 2, and possibly 3, are the pin status. The byte
> + * order is different than for the GET_STATUS
> + * command. Byte 1 is GPIOs 8 to 15, and byte 2 is
> + * GPIOs 0 to 7.
> + */
> +
> + handle_nested_irq(irq_find_mapping(dev->gpio.irq.domain,
> + CH341_GPIO_INT_LINE));
> +
> + ret = usb_submit_urb(dev->irq_urb, GFP_ATOMIC);
> + if (ret)
> + usb_unanchor_urb(dev->irq_urb);
Ditto. This isn't how anchors are used.
> + }
> +}
> +
> +static int ch341_gpio_irq_set_type(struct irq_data *data, unsigned int flow_type)
> +{
> + const unsigned long offset = irqd_to_hwirq(data);
> +
> + if (offset != CH341_GPIO_INT_LINE || flow_type != IRQ_TYPE_EDGE_RISING)
> + return -EINVAL;
Ok, I missed this check before, sorry. So you do have a single interrupt
line.
You should probably add a comment in the enable() callback since this is
easy to miss.
> +
> + return 0;
> +}
> +
> +static void ch341_gpio_irq_enable(struct irq_data *data)
> +{
> + struct ch341_gpio *dev = irq_data_get_irq_chip_data(data);
> + int ret;
> +
> + /*
> + * The URB might have just been unlinked in
> + * ch341_gpio_irq_disable, but the completion handler hasn't
> + * been called yet.
> + */
> + if (!usb_wait_anchor_empty_timeout(&dev->irq_urb_out, 5000))
> + usb_kill_anchored_urbs(&dev->irq_urb_out);
You cannot sleep in this function.
> +
> + usb_anchor_urb(dev->irq_urb, &dev->irq_urb_out);
> + ret = usb_submit_urb(dev->irq_urb, GFP_KERNEL);
> + if (ret)
> + usb_unanchor_urb(dev->irq_urb);
> +}
> +
> +static void ch341_gpio_irq_disable(struct irq_data *data)
> +{
> + struct ch341_gpio *dev = irq_data_get_irq_chip_data(data);
> +
> + usb_unlink_urb(dev->irq_urb);
> +}
> +
> +static int ch341_gpio_remove(struct platform_device *pdev)
> +{
> + struct ch341_gpio *dev = platform_get_drvdata(pdev);
> +
> + usb_kill_anchored_urbs(&dev->irq_urb_out);
Again, this is racy as the gpio chip is still registered. And you don't
need an anchor to stop a single URB.
> + gpiochip_remove(&dev->gpio);
> + usb_free_urb(dev->irq_urb);
> +
> + return 0;
> +}
> +
> +static const struct irq_chip ch341_irqchip = {
> + .name = "CH341",
> + .irq_set_type = ch341_gpio_irq_set_type,
> + .irq_enable = ch341_gpio_irq_enable,
> + .irq_disable = ch341_gpio_irq_disable,
> + .flags = IRQCHIP_IMMUTABLE,
> + GPIOCHIP_IRQ_RESOURCE_HELPERS,
> +};
> +
> +static int ch341_gpio_probe(struct platform_device *pdev)
> +{
> + struct ch341_ddata *ddata = dev_get_drvdata(pdev->dev.parent);
> + struct gpio_irq_chip *girq;
> + struct ch341_gpio *dev;
> + struct gpio_chip *gpio;
> + int ret;
> +
> + dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
> + if (dev == NULL)
> + return -ENOMEM;
> +
> + platform_set_drvdata(pdev, dev);
> + dev->ddata = ddata;
> + mutex_init(&dev->gpio_lock);
> +
> + gpio = &dev->gpio;
> + gpio->label = dev_name(&pdev->dev);
> + gpio->parent = &pdev->dev;
> + gpio->owner = THIS_MODULE;
> + gpio->get_direction = ch341_gpio_get_direction;
> + gpio->direction_input = ch341_gpio_direction_input;
> + gpio->direction_output = ch341_gpio_direction_output;
> + gpio->get = ch341_gpio_get;
> + gpio->get_multiple = ch341_gpio_get_multiple;
> + gpio->set = ch341_gpio_set;
> + gpio->set_multiple = ch341_gpio_set_multiple;
> + gpio->base = -1;
> + gpio->ngpio = CH341_GPIO_NUM_PINS;
> + gpio->can_sleep = true;
> +
> + girq = &gpio->irq;
> + gpio_irq_chip_set_chip(girq, &ch341_irqchip);
> + girq->handler = handle_simple_irq;
> + girq->default_type = IRQ_TYPE_NONE;
> +
> + /* Create an URB for handling interrupt */
> + dev->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
> + if (!dev->irq_urb)
> + return dev_err_probe(&pdev->dev, -ENOMEM, "Cannot allocate the int URB\n");
This isn't how dev_err_probe() is used.
And allocation failures are already logged so just return -ENOMEM here.
> +
> + usb_fill_int_urb(dev->irq_urb, ddata->usb_dev,
> + usb_rcvintpipe(ddata->usb_dev, ddata->ep_intr),
> + dev->irq_buf, CH341_USB_MAX_INTR_SIZE,
> + ch341_complete_intr_urb, dev, ddata->ep_intr_interval);
> +
> + init_usb_anchor(&dev->irq_urb_out);
> +
> + ret = gpiochip_add_data(gpio, dev);
> + if (ret) {
> + ret = dev_err_probe(&pdev->dev, ret, "Could not add GPIO\n");
> + goto release_urb;
> + }
> +
> + return 0;
> +
> +release_urb:
> + usb_free_urb(dev->irq_urb);
> +
> + return ret;
> +}
Johan
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 2/4] gpio: ch341: add GPIO MFD cell driver for the CH341
2022-06-20 10:25 ` Johan Hovold
@ 2022-06-20 16:08 ` Andy Shevchenko
2022-06-21 6:57 ` Johan Hovold
0 siblings, 1 reply; 18+ messages in thread
From: Andy Shevchenko @ 2022-06-20 16:08 UTC (permalink / raw)
To: Johan Hovold
Cc: frank zago, Greg Kroah-Hartman, Linux Kernel Mailing List,
Bartosz Golaszewski, Wolfram Sang, USB, Lee Jones, Linus Walleij,
open list:GPIO SUBSYSTEM, linux-i2c
On Mon, Jun 20, 2022 at 12:26 PM Johan Hovold <johan@kernel.org> wrote:
> On Wed, Jun 15, 2022 at 08:37:45PM -0500, frank zago wrote:
...
> > + /* Create an URB for handling interrupt */
> > + dev->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
> > + if (!dev->irq_urb)
> > + return dev_err_probe(&pdev->dev, -ENOMEM, "Cannot allocate the int URB\n");
>
> This isn't how dev_err_probe() is used.
While I agree on the below comment, what does this imply?
> And allocation failures are already logged so just return -ENOMEM here.
--
With Best Regards,
Andy Shevchenko
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 2/4] gpio: ch341: add GPIO MFD cell driver for the CH341
2022-06-20 16:08 ` Andy Shevchenko
@ 2022-06-21 6:57 ` Johan Hovold
0 siblings, 0 replies; 18+ messages in thread
From: Johan Hovold @ 2022-06-21 6:57 UTC (permalink / raw)
To: Andy Shevchenko
Cc: frank zago, Greg Kroah-Hartman, Linux Kernel Mailing List,
Bartosz Golaszewski, Wolfram Sang, USB, Lee Jones, Linus Walleij,
open list:GPIO SUBSYSTEM, linux-i2c
On Mon, Jun 20, 2022 at 06:08:19PM +0200, Andy Shevchenko wrote:
> On Mon, Jun 20, 2022 at 12:26 PM Johan Hovold <johan@kernel.org> wrote:
> > On Wed, Jun 15, 2022 at 08:37:45PM -0500, frank zago wrote:
>
> ...
>
> > > + /* Create an URB for handling interrupt */
> > > + dev->irq_urb = usb_alloc_urb(0, GFP_KERNEL);
> > > + if (!dev->irq_urb)
> > > + return dev_err_probe(&pdev->dev, -ENOMEM, "Cannot allocate the int URB\n");
> >
> > This isn't how dev_err_probe() is used.
>
> While I agree on the below comment, what does this imply?
That you should only use dev_err_probe() to handle -EPROBE_DEFER. That's
what it is was added for, documented as, and it is what the
implementation still tells you.
I see now that there has recently been some mission creep:
7065f92255bb ("driver core: Clarify that dev_err_probe() is OK even w/out -EPROBE_DEFER")
I'm not sure I agree with that, but fortunately we don't need to have
that debate in this case due to the below.
> > And allocation failures are already logged so just return -ENOMEM here.
Johan
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode
2022-06-16 1:37 ` [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode frank zago
@ 2022-06-27 14:04 ` Lee Jones
2022-06-27 14:28 ` Greg Kroah-Hartman
2022-07-04 10:09 ` Lee Jones
1 sibling, 1 reply; 18+ messages in thread
From: Lee Jones @ 2022-06-27 14:04 UTC (permalink / raw)
To: frank zago
Cc: Greg Kroah-Hartman, linux-kernel, Bartosz Golaszewski,
Wolfram Sang, Johan Hovold, linux-usb, Linus Walleij, linux-gpio,
linux-i2c
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@zago.net>
> ---
> 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@hardeman.nu>
> S: Maintained
> F: drivers/media/rc/winbond-cir.c
>
> +WINCHIPHEAD CH341 I2C/GPIO MFD DRIVER
> +M: Frank Zago <frank@zago.net>
> +L: linux-usb@vger.kernel.org
> +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@gmail.com>
> L: linux-watchdog@vger.kernel.org
> 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@schorcht.net)
> + * Copyright (c) 2016 Tse Lun Bien
> + * Copyright (c) 2014 Marco Gittler
> + * Copyright (c) 2006-2007 Till Harbaum (Till@Harbaum.org)
> + */
> +
> +#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@zago.net>");
> +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;
> +};
--
Lee Jones [李琼斯]
Principal Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
Follow Linaro: Facebook | Twitter | Blog
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode
2022-06-27 14:04 ` Lee Jones
@ 2022-06-27 14:28 ` Greg Kroah-Hartman
2022-06-27 14:43 ` Lee Jones
0 siblings, 1 reply; 18+ messages in thread
From: Greg Kroah-Hartman @ 2022-06-27 14:28 UTC (permalink / raw)
To: Lee Jones
Cc: frank zago, linux-kernel, Bartosz Golaszewski, Wolfram Sang,
Johan Hovold, linux-usb, Linus Walleij, linux-gpio, linux-i2c
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@zago.net>
> > ---
> > 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@hardeman.nu>
> > S: Maintained
> > F: drivers/media/rc/winbond-cir.c
> >
> > +WINCHIPHEAD CH341 I2C/GPIO MFD DRIVER
> > +M: Frank Zago <frank@zago.net>
> > +L: linux-usb@vger.kernel.org
> > +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@gmail.com>
> > L: linux-watchdog@vger.kernel.org
> > 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@schorcht.net)
> > + * Copyright (c) 2016 Tse Lun Bien
> > + * Copyright (c) 2014 Marco Gittler
> > + * Copyright (c) 2006-2007 Till Harbaum (Till@Harbaum.org)
> > + */
> > +
> > +#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@zago.net>");
> > +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...
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode
2022-06-27 14:28 ` Greg Kroah-Hartman
@ 2022-06-27 14:43 ` Lee Jones
2022-06-27 23:30 ` Frank Zago
0 siblings, 1 reply; 18+ messages in thread
From: Lee Jones @ 2022-06-27 14:43 UTC (permalink / raw)
To: Greg Kroah-Hartman
Cc: frank zago, linux-kernel, Bartosz Golaszewski, Wolfram Sang,
Johan Hovold, linux-usb, Linus Walleij, linux-gpio, linux-i2c
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@zago.net>
> > > ---
> > > 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@hardeman.nu>
> > > S: Maintained
> > > F: drivers/media/rc/winbond-cir.c
> > >
> > > +WINCHIPHEAD CH341 I2C/GPIO MFD DRIVER
> > > +M: Frank Zago <frank@zago.net>
> > > +L: linux-usb@vger.kernel.org
> > > +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@gmail.com>
> > > L: linux-watchdog@vger.kernel.org
> > > 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@schorcht.net)
> > > + * Copyright (c) 2016 Tse Lun Bien
> > > + * Copyright (c) 2014 Marco Gittler
> > > + * Copyright (c) 2006-2007 Till Harbaum (Till@Harbaum.org)
> > > + */
> > > +
> > > +#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@zago.net>");
> > > +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?
> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Thanks.
--
Lee Jones [李琼斯]
Principal Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
Follow Linaro: Facebook | Twitter | Blog
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode
2022-06-27 14:43 ` Lee Jones
@ 2022-06-27 23:30 ` Frank Zago
0 siblings, 0 replies; 18+ messages in thread
From: Frank Zago @ 2022-06-27 23:30 UTC (permalink / raw)
To: Lee Jones, Greg Kroah-Hartman
Cc: linux-kernel, Bartosz Golaszewski, Wolfram Sang, Johan Hovold,
linux-usb, Linus Walleij, linux-gpio, linux-i2c
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@zago.net>
>>>> ---
>>>> 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@hardeman.nu>
>>>> S: Maintained
>>>> F: drivers/media/rc/winbond-cir.c
>>>>
>>>> +WINCHIPHEAD CH341 I2C/GPIO MFD DRIVER
>>>> +M: Frank Zago <frank@zago.net>
>>>> +L: linux-usb@vger.kernel.org
>>>> +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@gmail.com>
>>>> L: linux-watchdog@vger.kernel.org
>>>> 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@schorcht.net)
>>>> + * Copyright (c) 2016 Tse Lun Bien
>>>> + * Copyright (c) 2014 Marco Gittler
>>>> + * Copyright (c) 2006-2007 Till Harbaum (Till@Harbaum.org)
>>>> + */
>>>> +
>>>> +#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@zago.net>");
>>>> +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
^ permalink raw reply [flat|nested] 18+ messages in thread
* Re: [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode
2022-06-16 1:37 ` [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode frank zago
2022-06-27 14:04 ` Lee Jones
@ 2022-07-04 10:09 ` Lee Jones
1 sibling, 0 replies; 18+ messages in thread
From: Lee Jones @ 2022-07-04 10:09 UTC (permalink / raw)
To: frank zago
Cc: Greg Kroah-Hartman, linux-kernel, Bartosz Golaszewski,
Wolfram Sang, Johan Hovold, linux-usb, Linus Walleij, linux-gpio,
linux-i2c
On Wed, 15 Jun 2022, frank zago wrote:
> 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@zago.net>
> ---
> 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@hardeman.nu>
> S: Maintained
> F: drivers/media/rc/winbond-cir.c
>
> +WINCHIPHEAD CH341 I2C/GPIO MFD DRIVER
> +M: Frank Zago <frank@zago.net>
> +L: linux-usb@vger.kernel.org
> +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@gmail.com>
> L: linux-watchdog@vger.kernel.org
> 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@schorcht.net)
> + * Copyright (c) 2016 Tse Lun Bien
> + * Copyright (c) 2014 Marco Gittler
> + * Copyright (c) 2006-2007 Till Harbaum (Till@Harbaum.org)
> + */
> +
> +#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",
> + },
> +};
These should both be on one line each.
> +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);
Why not use the devm_* version?
> +}
> +
> +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@zago.net>");
> +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 */
What definitions?
> +
> +#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;
> +};
--
Lee Jones [李琼斯]
Principal Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
Follow Linaro: Facebook | Twitter | Blog
^ permalink raw reply [flat|nested] 18+ messages in thread
end of thread, other threads:[~2022-07-04 10:09 UTC | newest]
Thread overview: 18+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-06-16 1:37 [PATCH v6 0/4] add driver for the WCH CH341 in I2C/GPIO mode frank zago
2022-06-16 1:37 ` [PATCH v6 1/4] mfd: ch341: add core driver for the WCH CH341 in I2C/SPI/GPIO mode frank zago
2022-06-27 14:04 ` Lee Jones
2022-06-27 14:28 ` Greg Kroah-Hartman
2022-06-27 14:43 ` Lee Jones
2022-06-27 23:30 ` Frank Zago
2022-07-04 10:09 ` Lee Jones
2022-06-16 1:37 ` [PATCH v6 2/4] gpio: ch341: add GPIO MFD cell driver for the CH341 frank zago
2022-06-17 8:29 ` Linus Walleij
2022-06-20 10:25 ` Johan Hovold
2022-06-20 16:08 ` Andy Shevchenko
2022-06-21 6:57 ` Johan Hovold
2022-06-16 1:37 ` [PATCH v6 3/4] i2c: ch341: add I2C " frank zago
2022-06-16 5:09 ` Randy Dunlap
2022-06-16 9:18 ` kernel test robot
2022-06-16 11:10 ` kernel test robot
2022-06-16 1:37 ` [PATCH v6 4/4] docs: misc: add documentation for ch341 driver frank zago
2022-06-20 10:08 ` [PATCH v6 0/4] add driver for the WCH CH341 in I2C/GPIO mode Johan Hovold
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