Re: [PATCH] input: Add Nintendo extension controller driver

From: Grant Likely
Date: Mon May 16 2011 - 17:56:38 EST


[fixed Oliver's email address]

On Mon, May 16, 2011 at 3:46 PM, Grant Likely <grant.likely@xxxxxxxxxxxx> wrote:
> This driver adds support for Nintendo Wiimote extension controllers
> directly attached to an i2c bus, such as when using an adaptor like
> the Wiichuck.
>
> Signed-off-by: Grant Likely <grant.likely@xxxxxxxxxxxx>

I should probably mention that I've only actually /tested/ this driver
with the Nunchuck. I'm getting a classic controller, but I don't have
it in my hands just yet. :-)

g.

> ---
>  drivers/input/joystick/Kconfig    |   13 +
>  drivers/input/joystick/Makefile   |    1
>  drivers/input/joystick/wiichuck.c |  441 +++++++++++++++++++++++++++++++++++++
>  3 files changed, 455 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/input/joystick/wiichuck.c
>
> diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig
> index 56eb471..5b7fba7 100644
> --- a/drivers/input/joystick/Kconfig
> +++ b/drivers/input/joystick/Kconfig
> @@ -193,6 +193,19 @@ config JOYSTICK_TWIDJOY
>          To compile this driver as a module, choose M here: the
>          module will be called twidjoy.
>
> +config JOYSTICK_WIICHUCK
> +       tristate "Nintendo Wiimote Extension connector on i2c bus"
> +       depends on I2C
> +       select INPUT_POLLDEV
> +       help
> +         Say Y here if you have a Nintendo Wiimote extension connector
> +         attached directly to an i2c bus, like the Sparcfun Wiichuck adapter
> +         board.  This driver supports both the Nunchuck and the Classic
> +         Controller extensions.
> +
> +         To compile this driver as a module, choose M here: the
> +         modules will be called wiichuck.
> +
>  config JOYSTICK_ZHENHUA
>        tristate "5-byte Zhenhua RC transmitter"
>        select SERIO
> diff --git a/drivers/input/joystick/Makefile b/drivers/input/joystick/Makefile
> index 92dc0de..78466d6 100644
> --- a/drivers/input/joystick/Makefile
> +++ b/drivers/input/joystick/Makefile
> @@ -29,6 +29,7 @@ obj-$(CONFIG_JOYSTICK_TMDC)           += tmdc.o
>  obj-$(CONFIG_JOYSTICK_TURBOGRAFX)      += turbografx.o
>  obj-$(CONFIG_JOYSTICK_TWIDJOY)         += twidjoy.o
>  obj-$(CONFIG_JOYSTICK_WARRIOR)         += warrior.o
> +obj-$(CONFIG_JOYSTICK_WIICHUCK)                += wiichuck.o
>  obj-$(CONFIG_JOYSTICK_XPAD)            += xpad.o
>  obj-$(CONFIG_JOYSTICK_ZHENHUA)         += zhenhua.o
>  obj-$(CONFIG_JOYSTICK_WALKERA0701)     += walkera0701.o
> diff --git a/drivers/input/joystick/wiichuck.c b/drivers/input/joystick/wiichuck.c
> new file mode 100644
> index 0000000..85a194f
> --- /dev/null
> +++ b/drivers/input/joystick/wiichuck.c
> @@ -0,0 +1,441 @@
> +/*
> + * i2c Wiichuck driver (Nintendo Wiimote accessory connector)
> + *
> + * This driver supports Nintendo Wiimote accessories like the Nunchuck and
> + * the Classic Controller connected to an i2c bus.
> + *
> + * Copyright (c) 2011 Secret Lab Technologies Ltd.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of version 2 of the GNU General Public License as
> + * published by the Free Software Foundation.
> + *
> + * This driver uses the polled input device abstraction to implement an
> + * input driver for Nintendo expansion devices wired up to an i2c bus.
> + *
> + * A state machine implements the protocol handling.  It starts in the
> + * DISCONNECTED state initially and polls every second waiting for a
> + * device to get attached, and reading the device id when one does.
> + * If the device is recognized, then the polling period is bumped up
> + * to 50ms, and the state machine enters into a loop alternating
> + * between writing the data address (which triggers data capture) and
> + * reading the data block out of the device.  If at any time the
> + * device is disconnected, then it goes back to DISCONNECTED state and
> + * drops the polling frequency back down to 1 second.
> + *
> + * A callback is implemented for each supported devices, currently the
> + * Nunchuck and the Classic Controller.  Wii Motion Plus has yet to be
> + * added.
> + */
> +
> +#include <linux/cache.h>
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/interrupt.h>
> +#include <linux/input.h>
> +#include <linux/input-polldev.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/slab.h>
> +
> +MODULE_AUTHOR("Grant Likely <grant.likely@xxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("Wiichuck (i2c Nintendo Wiimote accessory) driver");
> +MODULE_LICENSE("GPL");
> +
> +#define WIICHUCK_POLL_PERIOD   (1000)  /* 1 second */
> +#ifdef DEBUG
> +#define WIICHUCK_CAPTURE_PERIOD (500)  /* 1/2 second for debug */
> +#else
> +#define WIICHUCK_CAPTURE_PERIOD (100)  /* 100 milliseconds */
> +#endif /* DEBUG */
> +
> +enum wiichuck_state {
> +       WIICHUCK_STATE_DISCONNECTED = 0,
> +       WIICHUCK_STATE_DATA,
> +};
> +
> +struct wiichuck_device {
> +       struct input_polled_dev *poll_dev;
> +       struct i2c_client *i2c_client;
> +       int (*process)(struct wiichuck_device *wiichuck);
> +       enum wiichuck_state state;
> +
> +       /*
> +        * DMA buffer, with padding to give it its own cache line so that
> +        * the DMA streaming works on non-coherent architectures.
> +        * Question: Is this the proper pattern, and is this really necessary?
> +        */
> +       uint8_t pad1[L1_CACHE_BYTES];
> +       uint8_t buf[6];
> +       uint8_t pad2[L1_CACHE_BYTES];
> +};
> +
> +static int wiichuck_transfer(struct wiichuck_device *wiichuck,
> +                            int len, bool read)
> +{
> +       struct i2c_client *i2c = wiichuck->i2c_client;
> +       struct i2c_msg msg = {
> +               .addr = i2c->addr, .len = len, .buf = wiichuck->buf };
> +
> +       if (read)
> +               msg.flags = I2C_M_RD;
> +       return i2c_transfer(i2c->adapter, &msg, 1);
> +}
> +
> +static int wiichuck_write(struct wiichuck_device *wiichuck,
> +                          uint8_t addr, uint8_t val)
> +{
> +       wiichuck->buf[0] = addr;
> +       wiichuck->buf[1] = val;
> +       return wiichuck_transfer(wiichuck, 2, false);
> +}
> +
> +static inline int wiichuck_setaddr(struct wiichuck_device *wiichuck,
> +                                   uint8_t addr)
> +{
> +       wiichuck->buf[0] = addr;
> +       return wiichuck_transfer(wiichuck, 1, false);
> +}
> +
> +static inline int wiichuck_read(struct wiichuck_device *wiichuck, int len)
> +{
> +       return wiichuck_transfer(wiichuck, len, true);
> +}
> +
> +static inline bool WIIBTN(int val, int bit)
> +{
> +       return (val & BIT(bit)) == 0;
> +}
> +
> +static int wiichuck_process_unknown(struct wiichuck_device *wiichuck)
> +{
> +       return 0;
> +}
> +
> +static int wiichuck_process_nunchuck(struct wiichuck_device *wiichuck)
> +{
> +       struct input_dev *input_dev = wiichuck->poll_dev->input;
> +       uint8_t *b = wiichuck->buf;
> +       int ax, ay, az, rc;
> +
> +       rc = wiichuck_read(wiichuck, 6);
> +       if (rc < 0)
> +               return rc;
> +
> +       ax = (b[2] << 2) | ((b[5] >> 2) & 0x3);
> +       ay = (b[3] << 2) | ((b[5] >> 4) & 0x3);
> +       az = (b[4] << 2) | ((b[5] >> 6) & 0x3);
> +
> +       input_report_abs(input_dev, ABS_X, b[0]);
> +       input_report_abs(input_dev, ABS_Y, b[1]);
> +       input_report_abs(input_dev, ABS_RX, ax);
> +       input_report_abs(input_dev, ABS_RY, ax);
> +       input_report_abs(input_dev, ABS_RZ, ay);
> +       input_report_key(input_dev, BTN_C, WIIBTN(b[5], 1));
> +       input_report_key(input_dev, BTN_Z, WIIBTN(b[5], 0));
> +       input_sync(input_dev);
> +
> +       dev_dbg(&wiichuck->i2c_client->dev,
> +               "nunchuck: j=%.3i,%.3i a=%.3x,%.3x,%.3x c,z=%i,%i\n",
> +               b[0],b[1], ax,ay,az, WIIBTN(b[5], 1), WIIBTN(b[5], 0));
> +       return 0;
> +};
> +
> +static int wiichuck_process_classic(struct wiichuck_device *wiichuck)
> +{
> +       struct input_dev *input_dev = wiichuck->poll_dev->input;
> +       uint8_t *b = wiichuck->buf;
> +       int lx, ly, lt, rx, ry, rt, rc;
> +
> +       rc = wiichuck_read(wiichuck, 6);
> +       if (rc < 0)
> +               return rc;
> +
> +       /* Analog measurements; some values are split between registers */
> +       rx = ((b[0] >> 3) & 0x18) | ((b[1] >> 5) & 6) | ((b[2] >> 7) & 1);
> +       ry = b[2] & 0x1f;
> +       rt = b[3] & 0x1f;
> +       lx = b[0] & 0x3f;
> +       ly = b[1] & 0x3f;
> +       lt = ((b[2] >> 2) & 0x18) | ((b[3] >> 5) & 7);
> +
> +       input_report_abs(input_dev, ABS_HAT0X, lx); /* left joystick */
> +       input_report_abs(input_dev, ABS_HAT0Y, ly);
> +       input_report_abs(input_dev, ABS_BRAKE, lt); /* left trigger */
> +       input_report_abs(input_dev, ABS_HAT1X, rx); /* right joystick */
> +       input_report_abs(input_dev, ABS_HAT1Y, ry);
> +       input_report_abs(input_dev, ABS_GAS, rt); /* right trigger */
> +
> +       /* D-pad */
> +       input_report_abs(input_dev, ABS_HAT2X, WIIBTN(b[4],7) - WIIBTN(b[5],1));
> +       input_report_abs(input_dev, ABS_HAT2Y, WIIBTN(b[4],6) - WIIBTN(b[5],0));
> +
> +       /* Buttons */
> +       input_report_key(input_dev, BTN_TL, WIIBTN(b[4], 5)); /* left trigger */
> +       input_report_key(input_dev, BTN_SELECT, WIIBTN(b[4], 4)); /* minus */
> +       input_report_key(input_dev, BTN_MODE, WIIBTN(b[4], 3)); /* home */
> +       input_report_key(input_dev, BTN_START, WIIBTN(b[4], 2)); /* plus */
> +       input_report_key(input_dev, BTN_TR, WIIBTN(b[4], 1)); /* right trigger */
> +
> +       input_report_key(input_dev, BTN_TL2, WIIBTN(b[5], 7)); /* left z */
> +       input_report_key(input_dev, BTN_B, WIIBTN(b[5], 6));
> +       input_report_key(input_dev, BTN_Y, WIIBTN(b[5], 5));
> +       input_report_key(input_dev, BTN_A, WIIBTN(b[5], 4));
> +       input_report_key(input_dev, BTN_X, WIIBTN(b[5], 3));
> +       input_report_key(input_dev, BTN_TR2, WIIBTN(b[5], 2)); /* right z */
> +       input_sync(input_dev);
> +
> +       dev_dbg(&wiichuck->i2c_client->dev,
> +               "classic: r=%.3i,%.3i,%.3i l=%.3x,%.3x,%.3x b=%.2x,%.2x\n",
> +               lx,ly,lt, rx,ry,rt, b[4],b[5]);
> +       return 0;
> +};
> +
> +/**
> + * wiichuck_poll() - Protocol state machine implementation
> + *
> + * A state machine is used here to keep the protocol processing
> + * reentrant.  Any of the i2c transactions will indeed sleep because
> + * i2c transactions are slow, but there is a mandatory delay between
> + * triggering the data capture (set address) and reading the data
> + * back.  Using a state machine means the poll function can return and
> + * free up the worker thread while waiting for the data.
> + */
> +static void wiichuck_poll(struct input_polled_dev *poll_dev)
> +{
> +       struct wiichuck_device *wiichuck = poll_dev->private;
> +       int id;
> +
> +       switch (wiichuck->state) {
> +       case WIICHUCK_STATE_DISCONNECTED:
> +               /* Disable encryption */
> +               if (wiichuck_write(wiichuck, 0xf0, 0x55) < 0)
> +                       return;
> +               if (wiichuck_write(wiichuck, 0xfb, 0x00) < 0)
> +                       return;
> +
> +               /* Read device id */
> +               if (wiichuck_setaddr(wiichuck, 0xfe) < 0)
> +                       return;
> +               if (wiichuck_read(wiichuck, 2) < 0)
> +                       return;
> +               id = (wiichuck->buf[0] << 8) | wiichuck->buf[1];
> +
> +               switch (id) {
> +                       case 0x0000: /* Nunchuck */
> +                               wiichuck->process = wiichuck_process_nunchuck;
> +                               dev_info(&wiichuck->i2c_client->dev,
> +                                        "Connected Nunchuck\n");
> +                               break;
> +
> +                       case 0x0101: /* Classic Controller */
> +                               wiichuck->process = wiichuck_process_classic;
> +                               dev_info(&wiichuck->i2c_client->dev,
> +                                        "Connected Classic Controller\n");
> +
> +                       default: /* No connection or unsupported device */
> +                               wiichuck->process = wiichuck_process_unknown;
> +                               dev_dbg(&wiichuck->i2c_client->dev,
> +                                        "Connected unknown id: %x\n", id);
> +                               return;
> +               }
> +
> +               /* Setup the first data transfer */
> +               if (wiichuck_setaddr(wiichuck, 0) < 0)
> +                       return;
> +
> +               wiichuck->state = WIICHUCK_STATE_DATA;
> +               poll_dev->poll_interval = WIICHUCK_CAPTURE_PERIOD;
> +               break;
> +
> +       case WIICHUCK_STATE_DATA:
> +               /* Read the input report */
> +               if (wiichuck->process(wiichuck) < 0)
> +                       goto disconnect;
> +
> +               /* Setup the next transfer */
> +               if (wiichuck_setaddr(wiichuck, 0) < 0)
> +                       goto disconnect;
> +               break;
> +
> +       default:
> +               goto disconnect;
> +       }
> +       return;
> +
> + disconnect:
> +       dev_info(&wiichuck->i2c_client->dev, "disconnected\n");
> +       wiichuck->state = WIICHUCK_STATE_DISCONNECTED;
> +       poll_dev->poll_interval = WIICHUCK_POLL_PERIOD;
> +}
> +
> +/**
> + * wiichuck_open() - Set up initial state machine state
> + *
> + * Called exactly once the first time the device is opened by
> + * userspace.  Will not be called again unless all users close it
> + * before reopening.  This simply clears the state to disconnected and
> + * sets the poll rate back to the slow speed
> + */
> +static void wiichuck_open(struct input_polled_dev *poll_dev)
> +{
> +       struct wiichuck_device *wiichuck = poll_dev->private;
> +
> +       wiichuck->process = wiichuck_process_unknown;
> +       wiichuck->state = WIICHUCK_STATE_DISCONNECTED;
> +       wiichuck->poll_dev->poll_interval = WIICHUCK_POLL_PERIOD;
> +}
> +
> +static int __devinit wiichuck_probe(struct i2c_client *client,
> +                               const struct i2c_device_id *id)
> +{
> +       struct wiichuck_device *wiichuck;
> +       struct input_polled_dev *poll_dev;
> +       struct input_dev *input_dev;
> +       int rc;
> +
> +       wiichuck = kzalloc(sizeof(*wiichuck), GFP_KERNEL);
> +       if (!wiichuck)
> +               return -ENOMEM;
> +
> +       poll_dev = input_allocate_polled_device();
> +       if (!poll_dev) {
> +               rc = -ENOMEM;
> +               goto err_alloc;
> +       }
> +
> +       wiichuck->i2c_client = client;
> +       wiichuck->poll_dev = poll_dev;
> +
> +       poll_dev->private = wiichuck;
> +       poll_dev->poll = wiichuck_poll;
> +       poll_dev->open = wiichuck_open;
> +
> +       input_dev = poll_dev->input;
> +       input_dev->name = "Wiichuck expansion connector";
> +       input_dev->id.bustype = BUS_I2C;
> +       input_dev->dev.parent = &client->dev;
> +
> +       /* Declare the events generated by this driver */
> +       __set_bit(EV_ABS, input_dev->evbit);
> +       __set_bit(EV_KEY, input_dev->evbit);
> +
> +       /* Nunchuck ranges */
> +       __set_bit(ABS_X, input_dev->absbit); /* joystick */
> +       __set_bit(ABS_Y, input_dev->absbit);
> +       input_set_abs_params(input_dev, ABS_X, 30, 220, 4, 8);
> +       input_set_abs_params(input_dev, ABS_Y, 40, 200, 4, 8);
> +
> +       __set_bit(ABS_RX, input_dev->absbit); /* accelerometer */
> +       __set_bit(ABS_RY, input_dev->absbit);
> +       __set_bit(ABS_RZ, input_dev->absbit);
> +       input_set_abs_params(input_dev, ABS_RX, 0, 0x3ff, 4, 8);
> +       input_set_abs_params(input_dev, ABS_RY, 0, 0x3ff, 4, 8);
> +       input_set_abs_params(input_dev, ABS_RZ, 0, 0x3ff, 4, 8);
> +
> +       /* Nunchuck buttons */
> +       __set_bit(BTN_C, input_dev->keybit);
> +       __set_bit(BTN_Z, input_dev->keybit);
> +
> +       /* Classic ranges */
> +       __set_bit(ABS_HAT0X, input_dev->absbit); /* Left Joystick */
> +       __set_bit(ABS_HAT0Y, input_dev->absbit);
> +       input_set_abs_params(input_dev, ABS_HAT0X, 0, 63, 2, 4);
> +       input_set_abs_params(input_dev, ABS_HAT0Y, 0, 63, 2, 4);
> +
> +       __set_bit(ABS_HAT1X, input_dev->absbit); /* Right Joystick */
> +       __set_bit(ABS_HAT1Y, input_dev->absbit);
> +       input_set_abs_params(input_dev, ABS_HAT1X, 0, 31, 1, 2);
> +       input_set_abs_params(input_dev, ABS_HAT1Y, 0, 31, 1, 2);
> +
> +       __set_bit(ABS_HAT2X, input_dev->absbit); /* D-pad */
> +       __set_bit(ABS_HAT2Y, input_dev->absbit);
> +       input_set_abs_params(input_dev, ABS_HAT2X, -1, 1, 0, 0);
> +       input_set_abs_params(input_dev, ABS_HAT2Y, -1, 1, 0, 0);
> +
> +       __set_bit(ABS_BRAKE, input_dev->absbit); /* Left trigger */
> +       input_set_abs_params(input_dev, ABS_BRAKE, 0, 31, 1, 2);
> +       __set_bit(ABS_GAS, input_dev->absbit);
> +       input_set_abs_params(input_dev, ABS_GAS, 0, 31, 1, 2);
> +
> +       /* Classic buttons */
> +       __set_bit(BTN_TL, input_dev->keybit);
> +       __set_bit(BTN_SELECT, input_dev->keybit);
> +       __set_bit(BTN_MODE, input_dev->keybit);
> +       __set_bit(BTN_START, input_dev->keybit);
> +       __set_bit(BTN_TR, input_dev->keybit);
> +       __set_bit(BTN_TL2, input_dev->keybit);
> +       __set_bit(BTN_B, input_dev->keybit);
> +       __set_bit(BTN_Y, input_dev->keybit);
> +       __set_bit(BTN_A, input_dev->keybit);
> +       __set_bit(BTN_X, input_dev->keybit);
> +       __set_bit(BTN_TR2, input_dev->keybit);
> +
> +       i2c_set_clientdata(client, wiichuck);
> +
> +       /* Register the device; it is 'live' after this point */
> +       rc = input_register_polled_device(wiichuck->poll_dev);
> +       if (rc) {
> +               dev_err(&client->dev, "Failed to register input device\n");
> +               goto err_register;
> +       }
> +
> +       return 0;
> +
> + err_register:
> +       i2c_set_clientdata(client, NULL);
> +       input_free_polled_device(poll_dev);
> + err_alloc:
> +       kfree(wiichuck);
> +
> +       return rc;
> +}
> +
> +static int __devexit wiichuck_remove(struct i2c_client *client)
> +{
> +       struct wiichuck_device *wiichuck = i2c_get_clientdata(client);
> +
> +       i2c_set_clientdata(client, NULL);
> +       input_unregister_polled_device(wiichuck->poll_dev);
> +       input_free_polled_device(wiichuck->poll_dev);
> +       kfree(wiichuck);
> +
> +       return 0;
> +}
> +
> +static const struct i2c_device_id wiichuck_id[] = {
> +       { "wiichuck", 0 },
> +       { }
> +};
> +MODULE_DEVICE_TABLE(i2c, wiichuck_id);
> +
> +#ifdef CONFIG_OF
> +static struct of_device_id wiichuck_match_table[] __devinitdata = {
> +       { .compatible = "nintendo,wiimote-extension", },
> +       { }
> +};
> +#else
> +#define wiichuck_match_table NULL
> +#endif
> +
> +static struct i2c_driver wiichuck_driver = {
> +       .driver = {
> +               .name = "wiichuck",
> +               .owner = THIS_MODULE,
> +               .of_match_table = wiichuck_match_table,
> +       },
> +       .probe          = wiichuck_probe,
> +       .remove         = __devexit_p(wiichuck_remove),
> +       .id_table       = wiichuck_id,
> +};
> +
> +static int __init wiichuck_init(void)
> +{
> +       return i2c_add_driver(&wiichuck_driver);
> +}
> +module_init(wiichuck_init);
> +
> +static void __exit wiichuck_exit(void)
> +{
> +       i2c_del_driver(&wiichuck_driver);
> +}
> +module_exit(wiichuck_exit);
>
>



--
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
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