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This commit is contained in:
PaulStoffregen 2017-09-09 18:01:56 -07:00
parent c94c873bb2
commit c2adf01769
1 changed files with 27 additions and 1 deletions
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28
hid.cpp
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@ -25,6 +25,13 @@
#include "USBHost_t36.h" // Read this header first for key info
// This HID driver claims a USB interface and parses its incoming
// data (reports). It doesn't actually use the data, but it allows
// drivers which inherit the USBHIDInput base class to claim the
// top level collections within the reports. Those drivers get
// callbacks with the arriving data full decoded to data/usage
// pairs.
void USBHIDParser::init()
{
contribute_Pipes(mypipes, sizeof(mypipes)/sizeof(Pipe_t));
@ -167,6 +174,8 @@ void USBHIDParser::out_callback(const Transfer_t *transfer)
}
}
// When the device goes away, we need to call disconnect_collection()
// for all drivers which claimed a top level collection
void USBHIDParser::disconnect()
{
for (uint32_t i=0; i < TOPUSAGE_LIST_LEN; i++) {
@ -178,6 +187,7 @@ void USBHIDParser::disconnect()
}
}
// Called when the HID device sends a report
void USBHIDParser::in_data(const Transfer_t *transfer)
{
print("HID: ");
@ -199,6 +209,10 @@ void USBHIDParser::out_data(const Transfer_t *transfer)
{
}
// This no-inputs parse is meant to be used when we first get the
// HID report descriptor. It finds all the top level collections
// and allows drivers to claim them. This is always where we
// learn whether the reports will or will not use a Report ID byte.
void USBHIDParser::parse()
{
const uint8_t *p = descriptor;
@ -271,6 +285,9 @@ void USBHIDParser::parse()
}
}
// This is a list of all the drivers inherited from the USBHIDInput class.
// Unlike the list of USBDriver (managed in enumeration.cpp), drivers stay
// on this list even when they have claimed a top level collection.
USBHIDInput * USBHIDInput::list = NULL;
USBHIDInput::USBHIDInput()
@ -285,6 +302,9 @@ USBHIDInput::USBHIDInput()
}
}
// When a new top level collection is found, this function asks drivers
// if they wish to claim it. The driver taking ownership of the
// collection is returned, or NULL if no driver wants it.
USBHIDInput * USBHIDParser::find_driver(uint32_t topusage)
{
USBHIDInput *driver = USBHIDInput::list;
@ -297,6 +317,7 @@ USBHIDInput * USBHIDParser::find_driver(uint32_t topusage)
return NULL;
}
// Extract 1 to 32 bits from the data array, starting at bitindex.
static uint32_t bitfield(const uint8_t *data, uint32_t bitindex, uint32_t numbits)
{
uint32_t output = 0;
@ -317,6 +338,8 @@ static uint32_t bitfield(const uint8_t *data, uint32_t bitindex, uint32_t numbit
return output;
}
// convert a number with the specified number of bits from unsigned to signed,
// so the result is a proper 32 bit signed integer.
static int32_t signext(uint32_t num, uint32_t bitcount)
{
if (bitcount < 32 && bitcount > 0 && (num & (1 << (bitcount-1)))) {
@ -325,6 +348,7 @@ static int32_t signext(uint32_t num, uint32_t bitcount)
return (int32_t)num;
}
// convert a tag's value to a signed integer.
static int32_t signedval(uint32_t num, uint8_t tag)
{
tag &= 3;
@ -333,7 +357,8 @@ static int32_t signedval(uint32_t num, uint8_t tag)
return (int32_t)num;
}
// parse the report descriptor and use it to feed the fields of the report
// to the drivers which have claimed its top level collections
void USBHIDParser::parse(uint16_t type_and_report_id, const uint8_t *data, uint32_t len)
{
const uint8_t *p = descriptor;
@ -521,6 +546,7 @@ void USBHIDParser::parse(uint16_t type_and_report_id, const uint8_t *data, uint3
case 0xA8: // Delimiter (local)
default:
println("Ruh Roh, unsupported tag, not a good thing Scoob ", tag, HEX);
break;
}
if (reset_local) {
usage_count = 0;