Re: [PATCH] Support for controlling leds on xbox 360 pad.

From: Dmitry Torokhov
Date: Fri Jun 15 2007 - 00:15:43 EST


Hi Jan,

On Sunday 03 June 2007 14:02, Jan Kratochvil wrote:
> +       list_for_each_entry(pos_led, &xpad_led_list, node) {
> +               if (pos_led->id == i)
> +                       i++;
> +               else
> +                       break;
> +       }

I don't like this list business, it requires locking and frankly
is not needed.

> +
> +       if (i > 99)
> +               goto fail1;

... and this limitation as well.

How about the patch below instead?

--
Dmitry

Subject: Input: xpad - add support for leds on xbox 360 pad
From: Jan Kratochvil <honza@xxxxxxxx>

Input: xpad - add support for leds on xbox 360 pad

Export LEDs on Xbox360 pad via led subsystem as a single device in
/sys/class/leds/xpad[0-9]+.

Xbox360 pad has four leds, which form a circle. Unfortunately the leds
can't be controlled independently and can only display a predefined
set of patterns (for example one is turned on wile others are off or
a rotating pattern - 1-2-3-4). To activate a pattern one needs to send
a specific command to the device (see http://www.free60.org/wiki/Gamepad).

Led subsystem allows us to set brightness, but there is nothing like
brightness on this device. So brightness is actually interpreted as
the command (only values between 0 and 14 are accepted).

Signed-off-by: Jan Kratochvil <honza@xxxxxxxx>
Signed-off-by: Dmitry Torokhov <dtor@xxxxxxx>
---

drivers/input/joystick/Kconfig | 7 +
drivers/input/joystick/xpad.c | 190 +++++++++++++++++++++++++++++++----------
2 files changed, 155 insertions(+), 42 deletions(-)

Index: work/drivers/input/joystick/Kconfig
===================================================================
--- work.orig/drivers/input/joystick/Kconfig
+++ work/drivers/input/joystick/Kconfig
@@ -275,4 +275,11 @@ config JOYSTICK_XPAD_FF
---help---
Say Y here if you want to take advantage of xbox 360 rumble features.

+config JOYSTICK_XPAD_LEDS
+ bool "LED Support for Xbox360 controller 'BigX' LED"
+ depends on LEDS_CLASS && JOYSTICK_XPAD
+ ---help---
+ This option enables support for the LED which surrounds the Big X on
+ XBox 360 controller.
+
endif
Index: work/drivers/input/joystick/xpad.c
===================================================================
--- work.orig/drivers/input/joystick/xpad.c
+++ work/drivers/input/joystick/xpad.c
@@ -191,13 +191,18 @@ struct usb_xpad {
unsigned char *idata; /* input data */
dma_addr_t idata_dma;

-#ifdef CONFIG_JOYSTICK_XPAD_FF
+#if defined(CONFIG_JOYSTICK_XPAD_FF) || defined(CONFIG_JOYSTICK_XPAD_LEDS)
struct urb *irq_out; /* urb for interrupt out report */
unsigned char *odata; /* output data */
dma_addr_t odata_dma;
+ struct mutex odata_mutex;
+#endif
+
+#if defined(CONFIG_JOYSTICK_XPAD_LEDS)
+ struct xpad_led *led;
#endif

- char phys[65]; /* physical device path */
+ char phys[64]; /* physical device path */

int dpad_mapping; /* map d-pad to buttons or to axes */
int xtype; /* type of xbox device */
@@ -349,7 +354,7 @@ exit:
__FUNCTION__, retval);
}

-#ifdef CONFIG_JOYSTICK_XPAD_FF
+#if defined(CONFIG_JOYSTICK_XPAD_FF) || defined(CONFIG_JOYSTICK_XPAD_LEDS)
static void xpad_irq_out(struct urb *urb)
{
int retval;
@@ -376,29 +381,7 @@ exit:
__FUNCTION__, retval);
}

-static int xpad_play_effect(struct input_dev *dev, void *data,
- struct ff_effect *effect)
-{
- struct usb_xpad *xpad = input_get_drvdata(dev);
-
- if (effect->type == FF_RUMBLE) {
- __u16 strong = effect->u.rumble.strong_magnitude;
- __u16 weak = effect->u.rumble.weak_magnitude;
- xpad->odata[0] = 0x00;
- xpad->odata[1] = 0x08;
- xpad->odata[2] = 0x00;
- xpad->odata[3] = strong / 256;
- xpad->odata[4] = weak / 256;
- xpad->odata[5] = 0x00;
- xpad->odata[6] = 0x00;
- xpad->odata[7] = 0x00;
- usb_submit_urb(xpad->irq_out, GFP_KERNEL);
- }
-
- return 0;
-}
-
-static int xpad_init_ff(struct usb_interface *intf, struct usb_xpad *xpad)
+static int xpad_init_output(struct usb_interface *intf, struct usb_xpad *xpad)
{
struct usb_endpoint_descriptor *ep_irq_out;
int error = -ENOMEM;
@@ -411,6 +394,8 @@ static int xpad_init_ff(struct usb_inter
if (!xpad->odata)
goto fail1;

+ mutex_init(&xpad->odata_mutex);
+
xpad->irq_out = usb_alloc_urb(0, GFP_KERNEL);
if (!xpad->irq_out)
goto fail2;
@@ -423,25 +408,19 @@ static int xpad_init_ff(struct usb_inter
xpad->irq_out->transfer_dma = xpad->odata_dma;
xpad->irq_out->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

- input_set_capability(xpad->dev, EV_FF, FF_RUMBLE);
-
- error = input_ff_create_memless(xpad->dev, NULL, xpad_play_effect);
- if (error)
- goto fail2;
-
return 0;

fail2: usb_buffer_free(xpad->udev, XPAD_PKT_LEN, xpad->odata, xpad->odata_dma);
fail1: return error;
}

-static void xpad_stop_ff(struct usb_xpad *xpad)
+static void xpad_stop_output(struct usb_xpad *xpad)
{
if (xpad->xtype == XTYPE_XBOX360)
usb_kill_urb(xpad->irq_out);
}

-static void xpad_deinit_ff(struct usb_xpad *xpad)
+static void xpad_deinit_output(struct usb_xpad *xpad)
{
if (xpad->xtype == XTYPE_XBOX360) {
usb_free_urb(xpad->irq_out);
@@ -449,13 +428,130 @@ static void xpad_deinit_ff(struct usb_xp
xpad->odata, xpad->odata_dma);
}
}
+#else
+static int xpad_init_output(struct usb_interface *intf, struct usb_xpad *xpad) { return 0; }
+static void xpad_deinit_output(struct usb_xpad *xpad) {}
+static void xpad_stop_output(struct usb_xpad *xpad) {}
+#endif

+#ifdef CONFIG_JOYSTICK_XPAD_FF
+static int xpad_play_effect(struct input_dev *dev, void *data,
+ struct ff_effect *effect)
+{
+ struct usb_xpad *xpad = input_get_drvdata(dev);
+
+ if (effect->type == FF_RUMBLE) {
+ __u16 strong = effect->u.rumble.strong_magnitude;
+ __u16 weak = effect->u.rumble.weak_magnitude;
+ xpad->odata[0] = 0x00;
+ xpad->odata[1] = 0x08;
+ xpad->odata[2] = 0x00;
+ xpad->odata[3] = strong / 256;
+ xpad->odata[4] = weak / 256;
+ xpad->odata[5] = 0x00;
+ xpad->odata[6] = 0x00;
+ xpad->odata[7] = 0x00;
+ usb_submit_urb(xpad->irq_out, GFP_KERNEL);
+ }
+
+ return 0;
+}
+
+static int xpad_init_ff(struct usb_xpad *xpad)
+{
+ input_set_capability(xpad->dev, EV_FF, FF_RUMBLE);
+
+ return input_ff_create_memless(xpad->dev, NULL, xpad_play_effect);
+}
+
+#else
+static int xpad_init_ff(struct usb_xpad *xpad) { return 0; }
+#endif
+
+#if defined(CONFIG_JOYSTICK_XPAD_LEDS)
+#include <linux/leds.h>
+
+struct xpad_led {
+ char name[16];
+ struct led_classdev led_cdev;
+ struct usb_xpad *xpad;
+};
+
+static void xpad_send_led_command(struct usb_xpad *xpad, int command)
+{
+ if (command >= 0 && command < 14) {
+ mutex_lock(&xpad->odata_mutex);
+ xpad->odata[0] = 0x01;
+ xpad->odata[1] = 0x03;
+ xpad->odata[2] = command;
+ usb_submit_urb(xpad->irq_out, GFP_KERNEL);
+ mutex_unlock(&xpad->odata_mutex);
+ }
+}
+
+static void xpad_led_set(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ struct xpad_led *xpad_led = container_of(led_cdev,
+ struct xpad_led, led_cdev);
+
+ xpad_send_led_command(xpad_led->xpad, value);
+}
+
+static int xpad_led_probe(struct usb_xpad *xpad)
+{
+ static atomic_t led_seq = ATOMIC_INIT(0);
+ long led_no;
+ struct xpad_led *led;
+ struct led_classdev *led_cdev;
+ int error;
+
+ if (xpad->xtype != XTYPE_XBOX360)
+ return 0;
+
+ xpad->led = led = kzalloc(sizeof(struct xpad_led), GFP_KERNEL);
+ if (!led)
+ return -ENOMEM;
+
+ led_no = (long)atomic_inc_return(&led_no) - 1;
+
+ snprintf(led->name, sizeof(led->name), "xpad%ld", led_no);
+ led->xpad = xpad;
+
+ led_cdev = &led->led_cdev;
+ led_cdev->name = led->name;
+ led_cdev->brightness_set = xpad_led_set;
+
+ error = led_classdev_register(&xpad->udev->dev, led_cdev);
+ if (error) {
+ kfree(led);
+ xpad->led = NULL;
+ return error;
+ }
+
+ /*
+ * Light up the segment corresponding to controller number
+ */
+ xpad_send_led_command(xpad, (led_no % 4) + 2);
+
+ return 0;
+}
+
+static void xpad_led_disconnect(struct usb_xpad *xpad)
+{
+ struct xpad_led *xpad_led = xpad->led;
+
+ if (xpad_led) {
+ led_classdev_unregister(&xpad_led->led_cdev);
+ kfree(xpad_led->name);
+ }
+}
#else
-static int xpad_init_ff(struct usb_interface *intf, struct usb_xpad *xpad) { return 0; }
-static void xpad_stop_ff(struct usb_xpad *xpad) { }
-static void xpad_deinit_ff(struct usb_xpad *xpad) { }
+static int xpad_led_probe(struct usb_xpad *xpad) { return 0; }
+static void xpad_led_disconnect(struct usb_xpad *xpad) { }
#endif

+
static int xpad_open(struct input_dev *dev)
{
struct usb_xpad *xpad = input_get_drvdata(dev);
@@ -472,7 +568,7 @@ static void xpad_close(struct input_dev
struct usb_xpad *xpad = input_get_drvdata(dev);

usb_kill_urb(xpad->irq_in);
- xpad_stop_ff(xpad);
+ xpad_stop_output(xpad);
}

static void xpad_set_up_abs(struct input_dev *input_dev, signed short abs)
@@ -564,10 +660,18 @@ static int xpad_probe(struct usb_interfa
for (i = 0; xpad_abs_pad[i] >= 0; i++)
xpad_set_up_abs(input_dev, xpad_abs_pad[i]);

- error = xpad_init_ff(intf, xpad);
+ error = xpad_init_output(intf, xpad);
if (error)
goto fail2;

+ error = xpad_init_ff(xpad);
+ if (error)
+ goto fail3;
+
+ error = xpad_led_probe(xpad);
+ if (error)
+ goto fail3;
+
ep_irq_in = &intf->cur_altsetting->endpoint[0].desc;
usb_fill_int_urb(xpad->irq_in, udev,
usb_rcvintpipe(udev, ep_irq_in->bEndpointAddress),
@@ -578,12 +682,13 @@ static int xpad_probe(struct usb_interfa

error = input_register_device(xpad->dev);
if (error)
- goto fail3;
+ goto fail4;

usb_set_intfdata(intf, xpad);
return 0;

- fail3: usb_free_urb(xpad->irq_in);
+ fail4: usb_free_urb(xpad->irq_in);
+ fail3: xpad_deinit_output(xpad);
fail2: usb_buffer_free(udev, XPAD_PKT_LEN, xpad->idata, xpad->idata_dma);
fail1: input_free_device(input_dev);
kfree(xpad);
@@ -597,8 +702,9 @@ static void xpad_disconnect(struct usb_i

usb_set_intfdata(intf, NULL);
if (xpad) {
+ xpad_led_disconnect(xpad);
input_unregister_device(xpad->dev);
- xpad_deinit_ff(xpad);
+ xpad_deinit_output(xpad);
usb_free_urb(xpad->irq_in);
usb_buffer_free(xpad->udev, XPAD_PKT_LEN,
xpad->idata, xpad->idata_dma);
-
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