diff options
Diffstat (limited to 'Documentation/input/input-programming.txt')
| -rw-r--r-- | Documentation/input/input-programming.txt | 17 |
1 files changed, 9 insertions, 8 deletions
diff --git a/Documentation/input/input-programming.txt b/Documentation/input/input-programming.txt index d9d523099bb..47fc86830cd 100644 --- a/Documentation/input/input-programming.txt +++ b/Documentation/input/input-programming.txt @@ -42,8 +42,8 @@ static int __init button_init(void) goto err_free_irq; } - button_dev->evbit[0] = BIT(EV_KEY); - button_dev->keybit[LONG(BTN_0)] = BIT(BTN_0); + button_dev->evbit[0] = BIT_MASK(EV_KEY); + button_dev->keybit[BIT_WORD(BTN_0)] = BIT_MASK(BTN_0); error = input_register_device(button_dev); if (error) { @@ -79,7 +79,7 @@ In the _init function, which is called either upon module load or when booting the kernel, it grabs the required resources (it should also check for the presence of the device). -Then it allocates a new input device structure with input_aloocate_device() +Then it allocates a new input device structure with input_allocate_device() and sets up input bitfields. This way the device driver tells the other parts of the input systems what it is - what events can be generated or accepted by this input device. Our example device can only generate EV_KEY @@ -217,14 +217,15 @@ If you don't need absfuzz and absflat, you can set them to zero, which mean that the thing is precise and always returns to exactly the center position (if it has any). -1.4 NBITS(), LONG(), BIT() +1.4 BITS_TO_LONGS(), BIT_WORD(), BIT_MASK() ~~~~~~~~~~~~~~~~~~~~~~~~~~ -These three macros from input.h help some bitfield computations: +These three macros from bitops.h help some bitfield computations: - NBITS(x) - returns the length of a bitfield array in longs for x bits - LONG(x) - returns the index in the array in longs for bit x - BIT(x) - returns the index in a long for bit x + BITS_TO_LONGS(x) - returns the length of a bitfield array in longs for + x bits + BIT_WORD(x) - returns the index in the array in longs for bit x + BIT_MASK(x) - returns the index in a long for bit x 1.5 The id* and name fields ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |