On 07/10/2023 16:40, Anshul Dalal wrote: > A simple driver for a mini gamepad that communicates over i2c, the gamepad > has bidirectional thumb stick input and six buttons. > > The gamepad chip utilizes the open framework from Adafruit called 'Seesaw' > to transmit the ADC data for the joystick and digital pin state for the > buttons. I have only implemented the functionality required to receive the > thumb stick and button state. > > Steps in reading the gamepad state over i2c: > 1. Reset the registers > 2. Set the pin mode of the pins specified by the `BUTTON_MASK` to input > `BUTTON_MASK`: A bit-map for the six digital pins internally > connected to the joystick buttons. > 3. Enable internal pullup resistors for the `BUTTON_MASK` > 4. Bulk set the pin state HIGH for `BUTTON_MASK` > 5. Poll the device for button and joystick state done by: > `seesaw_read_data(struct i2c_client *client, struct seesaw_data *data)` > > Product page: > https://www.adafruit.com/product/5743 > Arduino driver: > https://github.com/adafruit/Adafruit_Seesaw > > Tested on RPi Zero 2W > > Signed-off-by: Anshul Dalal <anshulusr@xxxxxxxxx> > --- > MAINTAINERS | 7 + > drivers/input/joystick/Kconfig | 9 + > drivers/input/joystick/Makefile | 1 + > drivers/input/joystick/adafruit_seesaw.c | 275 +++++++++++++++++++++++ > 4 files changed, 292 insertions(+) > create mode 100644 drivers/input/joystick/adafruit_seesaw.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 81d5fc0bba68..cd4f9deb77e2 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -441,6 +441,13 @@ W: http://wiki.analog.com/AD7879 > W: https://ez.analog.com/linux-software-drivers > F: drivers/input/touchscreen/ad7879.c > > +ADAFRUIT MINI I2C GAMEPAD > +M: Anshul Dalal <anshulusr@xxxxxxxxx> > +L: linux-input@xxxxxxxxxxxxxxx > +S: Maintained > +F: Documentation/devicetree/bindings/input/adafruit_seesaw.yaml > +F: drivers/input/joystick/adafruit_seesaw.c > + > ADDRESS SPACE LAYOUT RANDOMIZATION (ASLR) > M: Jiri Kosina <jikos@xxxxxxxxxx> > S: Maintained > diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig > index ac6925ce8366..b8337edc6e22 100644 > --- a/drivers/input/joystick/Kconfig > +++ b/drivers/input/joystick/Kconfig > @@ -412,4 +412,13 @@ config JOYSTICK_SENSEHAT > To compile this driver as a module, choose M here: the > module will be called sensehat_joystick. > > +config JOYSTICK_SEESAW > + tristate "Adafruit Mini I2C Gamepad with Seesaw" > + depends on I2C > + help > + Say Y here if you want to use the Adafruit Mini I2C Gamepad. This does not look like correct indentation. Just look at other code and do not do it differently. > + > + To compile this driver as a module, choose M here: the module will be > + called adafruit_seesaw. > + > endif ... > + > +static int seesaw_probe(struct i2c_client *client) > +{ > + int err; > + struct seesaw_gamepad *private; > + unsigned char register_reset[] = { SEESAW_STATUS_BASE, > + SEESAW_STATUS_SWRST, 0xFF }; > + unsigned char get_hw_id[] = { SEESAW_STATUS_BASE, SEESAW_STATUS_HW_ID }; > + > + err = i2c_master_send(client, register_reset, sizeof(register_reset)); > + if (err < 0) > + return err; > + if (err != sizeof(register_reset)) > + return -EIO; > + mdelay(10); Why 10? This should be explained somehow in the code. > + > + private = devm_kzalloc(&client->dev, sizeof(*private), GFP_KERNEL); > + if (!private) > + return -ENOMEM; > + > + err = i2c_master_send(client, get_hw_id, sizeof(get_hw_id)); > + if (err < 0) > + return err; > + if (err != sizeof(get_hw_id)) > + return -EIO; > + err = i2c_master_recv(client, &private->hardware_id, 1); > + if (err < 0) > + return err; > + if (err != 1) > + return -EIO; > + > + dev_dbg(&client->dev, "Adafruit Seesaw Gamepad, Hardware ID: %02x\n", > + private->hardware_id); > + > + private->i2c_client = client; > + scnprintf(private->physical_path, sizeof(private->physical_path), > + "i2c/%s", dev_name(&client->dev)); > + i2c_set_clientdata(client, private); > + > + private->input_dev = devm_input_allocate_device(&client->dev); > + if (!private->input_dev) > + return -ENOMEM; > + > + private->input_dev->id.bustype = BUS_I2C; > + private->input_dev->name = "Adafruit Seesaw Gamepad"; > + private->input_dev->phys = private->physical_path; > + input_set_drvdata(private->input_dev, private); > + input_set_abs_params(private->input_dev, ABS_X, 0, > + SEESAW_JOYSTICK_MAX_AXIS, SEESAW_JOYSTICK_FUZZ, > + SEESAW_JOYSTICK_FLAT); > + input_set_abs_params(private->input_dev, ABS_Y, 0, > + SEESAW_JOYSTICK_MAX_AXIS, SEESAW_JOYSTICK_FUZZ, > + SEESAW_JOYSTICK_FLAT); > + input_set_capability(private->input_dev, EV_KEY, BTN_A); > + input_set_capability(private->input_dev, EV_KEY, BTN_B); > + input_set_capability(private->input_dev, EV_KEY, BTN_X); > + input_set_capability(private->input_dev, EV_KEY, BTN_Y); > + input_set_capability(private->input_dev, EV_KEY, BTN_START); > + input_set_capability(private->input_dev, EV_KEY, BTN_SELECT); > + > + err = input_setup_polling(private->input_dev, seesaw_poll); > + if (err) { > + dev_err(&client->dev, "failed to set up polling: %d\n", err); > + return err; > + } > + > + input_set_poll_interval(private->input_dev, > + SEESAW_GAMEPAD_POLL_INTERVAL); > + input_set_max_poll_interval(private->input_dev, > + SEESAW_GAMEPAD_POLL_MAX); > + input_set_min_poll_interval(private->input_dev, > + SEESAW_GAMEPAD_POLL_MIN); > + > + err = input_register_device(private->input_dev); > + if (err) { > + dev_err(&client->dev, "failed to register joystick: %d\n", err); > + return err; > + } > + > + /* Set Pin Mode to input and enable pull-up resistors */ > + unsigned char pin_mode[] = { SEESAW_GPIO_BASE, SEESAW_GPIO_DIRCLR_BULK, > + BUTTON_MASK >> 24, BUTTON_MASK >> 16, > + BUTTON_MASK >> 8, BUTTON_MASK }; > + err = i2c_master_send(client, pin_mode, sizeof(pin_mode)); > + pin_mode[1] = SEESAW_GPIO_PULLENSET; > + err |= i2c_master_send(client, pin_mode, sizeof(pin_mode)); > + pin_mode[1] = SEESAW_GPIO_BULK_SET; > + err |= i2c_master_send(client, pin_mode, sizeof(pin_mode)); > + if (err < 0) > + return err; > + if (err != sizeof(pin_mode)) > + return -EIO; > + > + return 0; > +} > + > +#ifdef CONFIG_OF > +static const struct of_device_id of_seesaw_match[] = { > + { > + .compatible = "adafruit,seesaw_gamepad", > + }, > + { /* Sentinel */ }, > +}; > +MODULE_DEVICE_TABLE(of, of_seesaw_match); > +#endif /* CONFIG_OF */ > + > +static const struct i2c_device_id seesaw_id_table[] = { { KBUILD_MODNAME, 0 }, > + { /* Sentinel */ } }; Please format it just like all other drivers have it. > +MODULE_DEVICE_TABLE(i2c, seesaw_id_table); > + > +static struct i2c_driver seesaw_driver = { > + .driver = { > + .name = SEESAW_DEVICE_NAME, > + .of_match_table = of_match_ptr(of_seesaw_match), > + }, > + .id_table = seesaw_id_table, > + .probe = seesaw_probe, Some mixed indentation before =. > +}; > +module_i2c_driver(seesaw_driver); > + > +MODULE_AUTHOR("Anshul Dalal <anshulusr@xxxxxxxxx>"); > +MODULE_DESCRIPTION("Adafruit Mini I2C Gamepad driver"); > +MODULE_LICENSE("GPL"); Best regards, Krzysztof
