Hello Jeff, thank you for your code-review. Could you please clarify a few things below? Just for my better understanding. 03.06.21 17:38, Jeff LaBundy пише: > Hi Oleh, > > This cleaned up rather nicely; just a few more comments from myself. > > On Wed, Jun 02, 2021 at 10:05:04PM +0300, Oleh Kravchenko wrote: >> A simple analog joystick built on Low Power ATtiny85 Microcontroller. >> Directional movements are measured with two 10 kΩ potentiometers >> connected with a gimbal mechanism that separates the horizontal and >> vertical movements. This joystick also has a select button that is actuated >> when the joystick is pressed down. >> >> Input events polled over the I2C bus. >> >> Product page: >> https://www.sparkfun.com/products/15168 >> Firmware and hardware sources: >> https://github.com/sparkfun/Qwiic_Joystick >> >> Tested on RPi4B and O4-iMX-NANO boards. >> >> Cc: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx> >> Cc: Device Tree mailing list <devicetree@xxxxxxxxxxxxxxx> >> Cc: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> >> Cc: Jiri Kosina <jikos@xxxxxxxx> >> Cc: Patchwork Bot <patchwork-bot@xxxxxxxxxx> >> Cc: Rob Herring <robh@xxxxxxxxxx> >> Signed-off-by: Oleh Kravchenko <oleg@xxxxxxxxxx> > > Typically a binding patch should be first in the series (i.e. [1/2]) > with the driver next (i.e. [2/2]) so that checkpatch does not signal > a warning about an undocumented compatible string. > >> --- >> >> Changes: >> - update code after code review >> >> drivers/input/joystick/Kconfig | 9 ++ >> drivers/input/joystick/Makefile | 1 + >> drivers/input/joystick/qwiic-joystick.c | 147 ++++++++++++++++++++++++ >> 3 files changed, 157 insertions(+) >> create mode 100644 drivers/input/joystick/qwiic-joystick.c >> >> diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig >> index 5e38899058c1..7dfe8ea90923 100644 >> --- a/drivers/input/joystick/Kconfig >> +++ b/drivers/input/joystick/Kconfig >> @@ -372,6 +372,15 @@ config JOYSTICK_PXRC >> To compile this driver as a module, choose M here: the >> module will be called pxrc. >> >> +config JOYSTICK_QWIIC >> + tristate "SparkFun Qwiic Joystick" >> + depends on I2C >> + help >> + Say Y here if you want to use the SparkFun Qwiic Joystick. >> + >> + To compile this driver as a module, choose M here: the >> + module will be called qwiic-joystick. >> + >> config JOYSTICK_FSIA6B >> tristate "FlySky FS-iA6B RC Receiver" >> select SERIO >> diff --git a/drivers/input/joystick/Makefile b/drivers/input/joystick/Makefile >> index 31d720c9e493..5174b8aba2dd 100644 >> --- a/drivers/input/joystick/Makefile >> +++ b/drivers/input/joystick/Makefile >> @@ -27,6 +27,7 @@ obj-$(CONFIG_JOYSTICK_MAPLE) += maplecontrol.o >> obj-$(CONFIG_JOYSTICK_N64) += n64joy.o >> obj-$(CONFIG_JOYSTICK_PSXPAD_SPI) += psxpad-spi.o >> obj-$(CONFIG_JOYSTICK_PXRC) += pxrc.o >> +obj-$(CONFIG_JOYSTICK_QWIIC) += qwiic-joystick.o >> obj-$(CONFIG_JOYSTICK_SIDEWINDER) += sidewinder.o >> obj-$(CONFIG_JOYSTICK_SPACEBALL) += spaceball.o >> obj-$(CONFIG_JOYSTICK_SPACEORB) += spaceorb.o >> diff --git a/drivers/input/joystick/qwiic-joystick.c b/drivers/input/joystick/qwiic-joystick.c >> new file mode 100644 >> index 000000000000..59c0f3e6ee75 >> --- /dev/null >> +++ b/drivers/input/joystick/qwiic-joystick.c >> @@ -0,0 +1,147 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * Copyright (C) 2021 Oleh Kravchenko <oleg@xxxxxxxxxx> >> + * >> + * SparkFun Qwiic Joystick >> + * Product page:https://www.sparkfun.com/products/15168 >> + * Firmware and hardware sources:https://github.com/sparkfun/Qwiic_Joystick >> + */ >> + >> +#include <linux/bits.h> >> +#include <linux/i2c.h> >> +#include <linux/input.h> > > Now that you are using byte order macros, you should explicitly include > linux/kernel.h. Where is requirement is described? I've found a lot of drivers without including linux/kernel.h but linux/bits.h >> +#include <linux/module.h> >> + >> +#define DRV_NAME "qwiic-joystick" >> + >> +#define QWIIC_JSK_REG_VERS 0 >> +#define QWIIC_JSK_REG_DATA 3 >> + >> +#define QWIIC_JSK_MAX_AXIS GENMASK(9, 0) >> +#define QWIIC_JSK_FUZZ 2 >> +#define QWIIC_JSK_FLAT 2 >> +#define QWIIC_JSK_POLL_INTERVAL 16 >> +#define QWIIC_JSK_POLL_MIN 8 >> +#define QWIIC_JSK_POLL_MAX 32 >> + >> +struct qwiic_jsk { >> + char phys[32]; >> + struct input_dev *dev; >> + struct i2c_client *client; >> +}; > > Nit: no need to align these declarations (here and a few other places). > >> + >> +struct qwiic_ver { >> + u8 addr; >> + u8 major; >> + u8 minor; >> +} __packed; > > 'addr' is unused so it can be dropped, in which case QWIIC_JSK_REG_VERS > would need to be increased to 1. > >> + >> +struct qwiic_data { >> + __be16 x; >> + __be16 y; >> + u8 thumb; >> +} __packed; >> + >> +static void qwiic_poll(struct input_dev *input) >> +{ >> + struct qwiic_jsk *priv; >> + struct qwiic_data data; >> + int err; >> + >> + priv = input_get_drvdata(input); >> + >> + err = i2c_smbus_read_i2c_block_data(priv->client, QWIIC_JSK_REG_DATA, >> + sizeof(data), (u8 *)&data); >> + if (err != sizeof(data)) >> + return; >> + >> + input_report_abs(input, ABS_X, be16_to_cpu(data.x) >> 6); >> + input_report_abs(input, ABS_Y, be16_to_cpu(data.y) >> 6); >> + input_report_key(input, BTN_THUMBL, !data.thumb); >> + input_sync(input); >> +} >> + >> +static int qwiic_probe(struct i2c_client *client, >> + const struct i2c_device_id *id) >> +{ >> + struct qwiic_jsk *priv; >> + struct qwiic_ver vers; >> + int err; >> + >> + err = i2c_smbus_read_i2c_block_data(client, QWIIC_JSK_REG_VERS, >> + sizeof(vers), (u8 *)&vers); >> + if (0 <= err && err < sizeof(vers)) >> + err = -EIO; >> + if (err < 0) >> + return err; > > I think this reads a little simpler as: > > if (err < 0) > return err; > if (err != sizeof(vers)) > return -EIO; > Can we sure that i2c_smbus_read_i2c_block_data() will read exact numbers of bytes? And if it read less, will return it an error? >> + >> + dev_dbg(&client->dev, "SparkFun Qwiic Joystick, FW: %d.%d\n", >> + vers.major, vers.minor); > > These should be printed as %u. > >> + >> + priv = devm_kzalloc(&client->dev, sizeof(*priv), GFP_KERNEL); >> + if (!priv) >> + return -ENOMEM; >> + >> + priv->client = client; >> + snprintf(priv->phys, sizeof(priv->phys), >> + "i2c/%s", dev_name(&client->dev)); >> + i2c_set_clientdata(client, priv); >> + >> + priv->dev = devm_input_allocate_device(&client->dev); >> + if (!priv->dev) >> + return -ENOMEM; >> + >> + priv->dev->id.bustype = BUS_I2C; >> + priv->dev->name = "SparkFun Qwiic Joystick"; >> + priv->dev->phys = priv->phys; >> + input_set_drvdata(priv->dev, priv); >> + >> + input_set_abs_params(priv->dev, ABS_X, 0, QWIIC_JSK_MAX_AXIS, >> + QWIIC_JSK_FUZZ, QWIIC_JSK_FLAT); >> + input_set_abs_params(priv->dev, ABS_Y, 0, QWIIC_JSK_MAX_AXIS, >> + QWIIC_JSK_FUZZ, QWIIC_JSK_FLAT); >> + input_set_capability(priv->dev, EV_KEY, BTN_THUMBL); >> + >> + err = input_setup_polling(priv->dev, qwiic_poll); >> + if (err) { >> + dev_err(&client->dev, "failed to set up polling: %d\n", err); >> + return err; >> + } >> + input_set_poll_interval(priv->dev, QWIIC_JSK_POLL_INTERVAL); >> + input_set_min_poll_interval(priv->dev, QWIIC_JSK_POLL_MIN); >> + input_set_max_poll_interval(priv->dev, QWIIC_JSK_POLL_MAX); >> + >> + err = input_register_device(priv->dev); >> + if (err) >> + dev_err(&client->dev, "failed to register joystick: %d\n", err); >> + >> + return err; >> +} >> + >> +#ifdef CONFIG_OF >> +static const struct of_device_id of_qwiic_match[] = { >> + { .compatible = "sparkfun,qwiic-joystick", }, >> + { }, >> +}; >> +MODULE_DEVICE_TABLE(of, of_qwiic_match); >> +#endif /* CONFIG_OF */ >> + >> +static const struct i2c_device_id qwiic_id_table[] = { >> + { KBUILD_MODNAME, 0 }, >> + { }, >> +}; >> +MODULE_DEVICE_TABLE(i2c, qwiic_id_table); >> + >> +static struct i2c_driver qwiic_driver = { >> + .driver = { >> + .name = DRV_NAME, >> + .of_match_table = of_match_ptr(of_qwiic_match), >> + }, >> + .id_table = qwiic_id_table, >> + .probe = qwiic_probe, >> +}; >> +module_i2c_driver(qwiic_driver); >> + >> +MODULE_AUTHOR("Oleh Kravchenko <oleg@xxxxxxxxxx>"); >> +MODULE_DESCRIPTION("SparkFun Qwiic Joystick driver"); >> +MODULE_LICENSE("GPL v2"); >> -- >> 2.26.3 >> > > Kind regards, > Jeff LaBundy > -- Best regards, Oleh Kravchenko
