| Message ID | 20220616013747.126051-1-frank@zago.net |
|---|---|
| Headers | show |
| Series | add driver for the WCH CH341 in I2C/GPIO mode | expand |
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.
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
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