usb_linux.c File Reference

#include "device.h"
#include "devnode.h"
#include "input.h"
#include "notify.h"
#include "usb.h"

Include dependency graph for usb_linux.c:

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Data Structures
struct	_model

Macros
#define	DEBUG
	all open usb devices have their system path names here in this array. More...
#define	TEST_RESET(op)
	TEST_RESET doesa "try / catch" for resetting the usb interface. More...
#define	N_MODELS   (sizeof(models) / sizeof(_model))

Functions
int	os_usbsend (usbdevice *kb, const uchar *out_msg, int is_recv, const char *file, int line)
	os_usbsend sends a data packet (MSG_SIZE = 64) Bytes long More...
int	os_usbrecv (usbdevice *kb, uchar *in_msg, const char *file, int line)
	os_usbrecv receives a max MSGSIZE long buffer from usb device More...
int	_nk95cmd (usbdevice *kb, uchar bRequest, ushort wValue, const char *file, int line)
	_nk95cmd If we control a non RGB keyboard, set the keyboard via ioctl with usbdevfs_ctrltransfer More...
void	os_sendindicators (usbdevice *kb)
void *	os_inputmain (void *context)
	os_inputmain This function is run in a separate thread and will be detached from the main thread, so it needs to clean up its own resources. More...
static int	usbunclaim (usbdevice *kb, int resetting)
void	os_closeusb (usbdevice *kb)
static int	usbclaim (usbdevice *kb)
int	os_resetusb (usbdevice *kb, const char *file, int line)
void	strtrim (char *string)
int	os_setupusb (usbdevice *kb)
int	usbadd (struct udev_device *dev, short vendor, short product)
static int	usb_add_device (struct udev_device *dev)
	Add a udev device. Returns 0 if device was recognized/added. More...
static void	usb_rm_device (struct udev_device *dev)
	usb_rm_device find the usb port to remove and close it via closeusb(). More...
static void	udev_enum ()
	udev_enum use the udev_enumerate_add_match_subsystem() to get all you need but only that. More...
int	usbmain ()
void	usbkill ()
	Stop the USB system. More...

Variables
static char	kbsyspath [9][FILENAME_MAX]
static struct udev *	udev
	struct udef is defined in /usr/include/libudev.h More...
pthread_t	usbthread
pthread_t	udevthread
static _model	models []

---

Data Structure Documentation

struct _model

Definition at line 658 of file usb_linux.c.

Collaboration diagram for _model:

Data Fields
const char *	name
short	number

Macro Definition Documentation

#define DEBUG

Definition at line 11 of file usb_linux.c.

#define N_MODELS   (sizeof(models) / sizeof(_model))

Definition at line 700 of file usb_linux.c.

Referenced by usb_add_device().

#define TEST_RESET

(

op

)

Value:

if(op){                                                                 \
        ckb_err_fn("resetusb failed: %s\n", file, line, strerror(errno));   \
        if(errno == EINTR || errno == EAGAIN)                               \
            return -1;              /* try again if status code says so */  \
        return -2;                  /* else, remove device */               \
    }

Definition at line 492 of file usb_linux.c.

Referenced by os_resetusb().

Function Documentation

int _nk95cmd	(	usbdevice *	kb,
		uchar	bRequest,
		ushort	wValue,
		const char *	file,
		int	line
	)

To send control packets to a non RGB non color K95 Keyboard, use this function. Normally it is called via the nk95cmd() macro.

If it is the wrong device for which the function is called, 0 is returned and nothing done. Otherwise a usbdevfs_ctrltransfer structure is filled and an USBDEVFS_CONTROL ioctl() called.

bRequestType	bRequest	wValue	EP	size	Timeout	data
0x40	see table below to switch hardware-modus at Keyboard	wValue	device	MSG_SIZE	5ms	the message buffer pointer
Host to Device, Type=Vendor, Recipient=Device	bRequest parameter	given wValue Parameter	device 0	0 data to write	5000	null

If a 0 or a negative error number is returned by the ioctl, an error message is shown depending on the errno or "No data written" if retval was 0. In either case 1 is returned to indicate the error. If the ioctl returned a value > 0, 0 is returned to indicate no error.

Currently the following combinations for bRequest and wValue are used:

Device	what it might to do	constant	bRequest	wValue
non RGB Keyboard	set HW-modus on (leave the ckb driver)	HWON	0x0002	0x0030
non RGB Keyboard	set HW-modus off (initialize the ckb driver)	HWOFF	0x0002	0x0001
non RGB Keyboard	set light modus M1 in single-color keyboards	NK95_M1	0x0014	0x0001
non RGB Keyboard	set light modus M2 in single-color keyboards	NK95_M2	0x0014	0x0002
non RGB Keyboard	set light modus M3 in single-color keyboards	NK95_M3	0x0014	0x0003

See Also

usb.h

Definition at line 189 of file usb_linux.c.

References ckb_err_fn, usbdevice::handle, P_K95_NRGB, and usbdevice::product.

                                                                                      {
    if(kb->product != P_K95_NRGB)
        return 0;
    struct usbdevfs_ctrltransfer transfer = { 0x40, bRequest, wValue, 0, 0, 5000, 0 };
    int res = ioctl(kb->handle - 1, USBDEVFS_CONTROL, &transfer);
    if(res <= 0){
        ckb_err_fn("%s\n", file, line, res ? strerror(errno) : "No data written");
        return 1;
    }
    return 0;
}

void os_closeusb

(

usbdevice *

kb

)

os_closeusb unclaim it, destroy the udev device and clear data structures at kb

os_closeusb is the linux specific implementation for closing an active usb port.
If a valid handle is given in the kb structure, the usb port is unclaimed (usbunclaim()).
The device in unrefenced via library function udev_device_unref().
handle, udev and the first char of kbsyspath are cleared to 0 (empty string for kbsyspath).

Definition at line 448 of file usb_linux.c.

References usbdevice::handle, INDEX_OF, kbsyspath, keyboard, usbdevice::udev, and usbunclaim().

Referenced by closeusb().

                               {
    if(kb->handle){
        usbunclaim(kb, 0);
        close(kb->handle - 1);
    }
    if(kb->udev)
        udev_device_unref(kb->udev);
    kb->handle = 0;
    kb->udev = 0;
    kbsyspath[INDEX_OF(kb, keyboard)][0] = 0;
}

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void* os_inputmain

(

void *

context

)

os_inputmain is run in a separate thread and will be detached from the main thread, so it needs to clean up its own resources.

Todo:

This function is a collection of many tasks. It should be divided into several sub-functions for the sake of greater convenience:

1. set up an URB (Userspace Ressource Buffer) to communicate with the USBDEVFS_* ioctl()s
2. perform the ioctl()
3. interpretate the information got into the URB buffer or handle error situations and retry operation or leave the endless loop
4. inform the os about the data
5. loop endless via 2.
6. if endless loop has gone, deinitalize the interface, free buffers etc.
7. return null

Here the actions in detail:

Monitor input transfers on all endpoints for non-RGB devices For RGB, monitor all but the last, as it's used for input/output

Get an usbdevfs_urb data structure and clear it via memset()

Hopefully the buffer lengths are equal for all devices with congruent types. You can find out the correctness for your device with lsusb –v or similar on macOS. Currently the following combinations are known and implemented:

device	detect with macro combination	endpoint #	buffer-length
each	none	0	8, 64 for FW v3
RGB Mouse	IS_RGB && IS_MOUSE	1	10
RGB Keyboard	IS_RGB && !IS_MOUSE	1	21
RGB Mouse or Keyboard	IS_RGB	2	MSG_SIZE (64)
non RGB Mouse or Keyboard	!IS_RGB	1	4
non RGB Mouse or Keyboard	!IS_RGB	2	15

Now submit all the URBs via ioctl(USBDEVFS_SUBMITURB) with type USBDEVFS_URB_TYPE_INTERRUPT (the endpoints are defined as type interrupt). Endpoint number is 0x80..0x82 or 0x83, depending on the model.

The userSpaceFS knows the URBs now, so start monitoring input

if the ioctl returns something != 0, let's have a deeper look what happened. Broken devices or shutting down the entire system leads to closing the device and finishing this thread.

If just an EPIPE ocurred, give the device a CLEAR_HALT and resubmit the URB.

A correct REAPURB returns a Pointer to the URB which we now have a closer look into. Lock all following actions with imutex.

Process the input depending on type of device. Interprete the actual size of the URB buffer

device	detect with macro combination	seems to be endpoint #	actual buffer-length	function called
mouse (RGB and non RGB)	IS_MOUSE	nA	8, 10 or 11	hid_mouse_translate()
mouse (RGB and non RGB)	IS_MOUSE	nA	MSG_SIZE (64)	corsair_mousecopy()
RGB Keyboard	IS_RGB && !IS_MOUSE	1	8 (BIOS Mode)	hid_kb_translate()
RGB Keyboard	IS_RGB && !IS_MOUSE	2	5 or 21, KB inactive!	hid_kb_translate()
RGB Keyboard	IS_RGB && !IS_MOUSE	3?	MSG_SIZE	corsair_kbcopy()
non RGB Keyboard	!IS_RGB && !IS_MOUSE	nA	nA	hid_kb_translate()

The input data is transformed and copied to the kb structure. Now give it to the OS and unlock the imutex afterwards.

Re-submit the URB for the next run.

If the endless loop is terminated, clean up by discarding the URBs via ioctl(USBDEVFS_DISCARDURB), free the URB buffers and return a null pointer as thread exit code.

Definition at line 248 of file usb_linux.c.

References usbdevice::active, ckb_err, ckb_info, corsair_kbcopy(), corsair_mousecopy(), devpath, usbdevice::epcount, usbdevice::fwversion, usbdevice::handle, hid_kb_translate(), hid_mouse_translate(), imutex, INDEX_OF, usbdevice::input, inputupdate(), IS_MOUSE, IS_RGB, keyboard, usbinput::keys, MSG_SIZE, usbdevice::product, usbinput::rel_x, usbinput::rel_y, and usbdevice::vendor.

Referenced by _setupusb().

                                 {
    usbdevice* kb = context;
    int fd = kb->handle - 1;
    short vendor = kb->vendor, product = kb->product;
    int index = INDEX_OF(kb, keyboard);
    ckb_info("Starting input thread for %s%d\n", devpath, index);

    int urbcount = IS_RGB(vendor, product) ? (kb->epcount - 1) : kb->epcount;
    if (urbcount == 0) {
        ckb_err("urbcount = 0, so there is nothing to claim in os_inputmain()\n");
        return 0;
    }

    struct usbdevfs_urb urbs[urbcount + 1];
    memset(urbs, 0, sizeof(urbs));

    urbs[0].buffer_length = (kb->fwversion >= 0x300 ? MSG_SIZE : 8);
    if(urbcount > 1 && IS_RGB(vendor, product)) {
        if(IS_MOUSE(vendor, product))
            urbs[1].buffer_length = 10;
        else
            urbs[1].buffer_length = 21;
        urbs[2].buffer_length = MSG_SIZE;
        if(urbcount != 3)
            urbs[urbcount - 1].buffer_length = MSG_SIZE;
    } else if(kb->fwversion < 0x300) {
            urbs[1].buffer_length = 4;
            urbs[2].buffer_length = 15;
    }

    for(int i = 0; i < urbcount; i++){
        urbs[i].type = USBDEVFS_URB_TYPE_INTERRUPT;
        urbs[i].endpoint = 0x80 | (i + 1);
        urbs[i].buffer = malloc(urbs[i].buffer_length);
        ioctl(fd, USBDEVFS_SUBMITURB, urbs + i);
    }

    while (1) {
        struct usbdevfs_urb* urb = 0;

        if (ioctl(fd, USBDEVFS_REAPURB, &urb)) {
            if (errno == ENODEV || errno == ENOENT || errno == ESHUTDOWN)
                // Stop the thread if the handle closes
                break;
            else if(errno == EPIPE && urb){
                ioctl(fd, USBDEVFS_CLEAR_HALT, &urb->endpoint);
                // Re-submit the URB
                if(urb)
                    ioctl(fd, USBDEVFS_SUBMITURB, urb);
                urb = 0;
            }
            continue;
        }

        if (urb) {

            pthread_mutex_lock(imutex(kb));
            // EP workaround for FWv3
            // Corsair input comes through 0x81, but case 1 in keymap.c is used for 6KRO
            uchar urbendpoint = (kb->fwversion >= 0x300 ? 2 : (urb->endpoint & 0xF));
            if(IS_MOUSE(vendor, product)){
                switch(urb->actual_length){
                case 8:
                case 10:
                case 11:
                    // HID mouse input
                    hid_mouse_translate(kb->input.keys, &kb->input.rel_x, &kb->input.rel_y, -urbendpoint, urb->actual_length, urb->buffer, kb->fwversion);
                    break;
                case MSG_SIZE:
                    // Corsair mouse input
                    corsair_mousecopy(kb->input.keys, -urbendpoint, urb->buffer);
                    break;
                }
            } else if(IS_RGB(vendor, product)){
                switch(urb->actual_length){
                case 8:
                    // RGB EP 1: 6KRO (BIOS mode) input
                    hid_kb_translate(kb->input.keys, -1, urb->actual_length, urb->buffer);
                    break;
                case 21:
                case 5:
                    // RGB EP 2: NKRO (non-BIOS) input. Accept only if keyboard is inactive
                    if(!kb->active)
                        hid_kb_translate(kb->input.keys, -2, urb->actual_length, urb->buffer);
                    break;
                case MSG_SIZE:
                    // RGB EP 3: Corsair input
                    corsair_kbcopy(kb->input.keys, -urbendpoint, urb->buffer);
                    break;
                }
            } else {
                // Non-RGB input
                hid_kb_translate(kb->input.keys, urb->endpoint & 0xF, urb->actual_length, urb->buffer);
            }
            inputupdate(kb);
            pthread_mutex_unlock(imutex(kb));

            ioctl(fd, USBDEVFS_SUBMITURB, urb);
            urb = 0;
        }
    }

    ckb_info("Stopping input thread for %s%d\n", devpath, index);
    for(int i = 0; i < urbcount; i++){
        ioctl(fd, USBDEVFS_DISCARDURB, urbs + i);
        free(urbs[i].buffer);
    }
    return 0;
}

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int os_resetusb	(	usbdevice *	kb,
		const char *	file,
		int	line
	)

os_resetusb is the os specific implementation for resetting usb

Try to reset an usb device in a linux user space driver.

1. unclaim the device, but do not reconnect the system driver (second param resetting = true)
2. reset the device via USBDEVFS_RESET command
3. claim the device again. Returns 0 on success, -2 if device should be removed and -1 if reset should by tried again

Todo:

it seems that no one wants to try the reset again. But I'v seen it somewhere...

Definition at line 510 of file usb_linux.c.

References usbdevice::handle, TEST_RESET, usbclaim(), and usbunclaim().

Referenced by _resetusb().

                                                           {
    TEST_RESET(usbunclaim(kb, 1));
    TEST_RESET(ioctl(kb->handle - 1, USBDEVFS_RESET));
    TEST_RESET(usbclaim(kb));
    // Success!
    return 0;
}

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void os_sendindicators

(

usbdevice *

kb

)

os_sendindicators update the indicators for the special keys (Numlock, Capslock and what else?)

os_sendindicators update the indicators for the special keys (Numlock, Capslock and what else?)

Read the data from kb->ileds ans send them via ioctl() to the keyboard.

bRequestType	bRequest	wValue	EP	size	Timeout	data
0x21	0x09	0x0200	Interface 0	MSG_SIZE 1 Byte	timeout 0,5ms	the message buffer pointer
Host to Device, Type=Class, Recipient=Interface (why not endpoint?)	9 = SEND?	specific	0	1	500	struct* kb->ileds

The ioctl command is USBDEVFS_CONTROL.

Definition at line 214 of file usb_linux.c.

References ckb_err, usbdevice::fwversion, usbdevice::handle, usbdevice::ileds, and usb_tryreset().

Referenced by updateindicators_kb().

                                      {
    static int countForReset = 0;
    void *ileds;
    ushort leds;
    if(kb->fwversion >= 0x300) {
        leds = (kb->ileds << 8) | 0x0001;
        ileds = &leds;
    }
    else {
        ileds = &kb->ileds;
    }
    struct usbdevfs_ctrltransfer transfer = { 0x21, 0x09, 0x0200, 0x00, (kb->fwversion >= 0x300 ? 2 : 1), 500, ileds };
    int res = ioctl(kb->handle - 1, USBDEVFS_CONTROL, &transfer);
    if(res <= 0) {
        ckb_err("%s\n", res ? strerror(errno) : "No data written");
        if (usb_tryreset(kb) == 0 && countForReset++ < 3) {
            os_sendindicators(kb);
        }
    }
}

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int os_setupusb

(

usbdevice *

kb

)

os_setupusb OS-specific setup for a specific usb device.

Perform the operating system-specific opening of the interface in os_setupusb(). As a result, some parameters should be set in kb (name, serial, fwversion, epcount = number of usb endpoints), and all endpoints should be claimed with usbclaim(). Claiming is the only point where os_setupusb() can produce an error (-1).

• Copy device description and serial
• Copy firmware version (needed to determine USB protocol)
• Do some output about connecting interfaces
• Claim the USB interfaces

Todo:

in these modules a pullrequest is outstanding

< Try to reset the device and recall the function

< Don't do this endless in recursion

< os_setupusb() has a return value (used as boolean)

Definition at line 548 of file usb_linux.c.

References ckb_err, ckb_info, devpath, usbdevice::epcount, usbdevice::fwversion, INDEX_OF, KB_NAME_LEN, keyboard, usbdevice::name, usbdevice::serial, SERIAL_LEN, strtrim(), usbdevice::udev, usb_tryreset(), and usbclaim().

Referenced by _setupusb().

                               {
    struct udev_device* dev = kb->udev;
    const char* name = udev_device_get_sysattr_value(dev, "product");
    if(name)
        strncpy(kb->name, name, KB_NAME_LEN);
    strtrim(kb->name);
    const char* serial = udev_device_get_sysattr_value(dev, "serial");
    if(serial)
        strncpy(kb->serial, serial, SERIAL_LEN);
    strtrim(kb->serial);
    const char* firmware = udev_device_get_sysattr_value(dev, "bcdDevice");
    if(firmware)
        sscanf(firmware, "%hx", &kb->fwversion);
    else
        kb->fwversion = 0;
    int index = INDEX_OF(kb, keyboard);

    ckb_info("Connecting %s at %s%d\n", kb->name, devpath, index);

    const char* ep_str = udev_device_get_sysattr_value(dev, "bNumInterfaces");
#ifdef DEBUG
    ckb_info("claiming interfaces. name=%s, firmware=%s; ep_str=%s\n", name, firmware, ep_str);
#endif //DEBUG
    kb->epcount = 0;
    if(ep_str)
        sscanf(ep_str, "%d", &kb->epcount);
    if(kb->epcount < 2){
        // IF we have an RGB KB with 0 or 1 endpoints, it will be in BIOS mode.
        ckb_err("Unable to read endpoint count from udev, assuming %d and reading >>%s<< or device is in BIOS mode\n", kb->epcount, ep_str);
        if (usb_tryreset(kb) == 0) { 
            static int retryCount = 0; 
            if (retryCount++ < 5) {
                return os_setupusb(kb); 
            }
        }
        return -1;
        // ToDo are there special versions we have to detect? If there are, that was the old code to handle it:
        // This shouldn't happen, but if it does, assume EP count based onckb_warn what the device is supposed to have
        // kb->epcount = (HAS_FEATURES(kb, FEAT_RGB) ? 4 : 3);
        // ckb_warn("Unable to read endpoint count from udev, assuming %d and reading >>%s<<...\n", kb->epcount, ep_str);
    }
    if(usbclaim(kb)){
        ckb_err("Failed to claim interfaces: %s\n", strerror(errno));
        return -1;
    }
    return 0;
}

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int os_usbrecv	(	usbdevice *	kb,
		uchar *	in_msg,
		const char *	file,
		int	line
	)

os_usbrecv does what its name says:

The comment at the beginning of the procedure causes the suspicion that the firmware versionspecific distinction is missing for receiving from usb endpoint 3 or 4. The commented code contains only the reception from EP4, but this may be wrong for a software version 2.0 or higher (see the code for os-usbsend ()).

So all the receiving is done via an ioctl() like in os_usbsend. The ioctl() is given a struct usbdevfs_ctrltransfer, in which the relevant parameters are entered:

bRequestType	bRequest	wValue	EP	size	Timeout	data
0xA1	0x01	0x0200	endpoint to be addressed from epcount - 1	MSG_SIZE	5ms	the message buffer pointer
Device to Host, Type=Class, Recipient=Interface	1 = RECEIVE?	specific	Interface #	64	5000	in_msg

The ioctl() returns the number of bytes received. Here is the usual check again:

• If the return value is -1 AND the error is a timeout (ETIMEOUT), os_usbrecv() will return -1 to indicate that it is probably a recoverable problem and a retry is recommended.
• For another negative value or other error identifier OR 0 bytes are received, 0 is returned as an identifier for a heavy error.
• In all other cases, the function returns the number of bytes received.

If this is not the entire blocksize (MSG_SIZE bytes), an error message is issued on the standard error channel [warning "Read YY bytes (expected 64)"].

Definition at line 130 of file usb_linux.c.

References ckb_err_fn, ckb_warn_fn, usbdevice::epcount, usbdevice::handle, and MSG_SIZE.

Referenced by _usbrecv().

                                                                        {
    int res;
    // This is what CUE does, but it doesn't seem to work on linux.
    /*if(kb->fwversion >= 0x130){
        struct usbdevfs_bulktransfer transfer = {0};
        transfer.ep = 0x84;
        transfer.len = MSG_SIZE;
        transfer.timeout = 5000;
        transfer.data = in_msg;
        res = ioctl(kb->handle - 1, USBDEVFS_BULK, &transfer);
    } else {*/
        struct usbdevfs_ctrltransfer transfer = { 0xa1, 0x01, 0x0300, kb->epcount - 1, MSG_SIZE, 5000, in_msg };
        res = ioctl(kb->handle - 1, USBDEVFS_CONTROL, &transfer);
    //}
    if(res <= 0){
        ckb_err_fn("%s\n", file, line, res ? strerror(errno) : "No data read");
        if(res == -1 && errno == ETIMEDOUT)
            return -1;
        else
            return 0;
    } else if(res != MSG_SIZE)
        ckb_warn_fn("Read %d bytes (expected %d)\n", file, line, res, MSG_SIZE);
#ifdef DEBUG_USB_RECV
    char converted[MSG_SIZE*3 + 1];
    for(int i=0;i<MSG_SIZE;i++)
        sprintf(&converted[i*3], "%02x ", in_msg[i]);
    ckb_warn_fn("Recv %s\n", file, line, converted);
#endif
    return res;
}

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int os_usbsend	(	usbdevice *	kb,
		const uchar *	out_msg,
		int	is_recv,
		const char *	file,
		int	line
	)

os_usbsend has two functions:

• if is_recv == false, it tries to send a given MSG_SIZE buffer via the usb interface given with kb.
• otherwise a request is sent via the usb device to initiate the receiving of a message from the remote device.

The functionality for sending distinguishes two cases, depending on the version number of the firmware of the connected device:
If the firmware is less or equal 1.2, the transmission is done via an ioctl(). The ioctl() is given a struct usbdevfs_ctrltransfer, in which the relevant parameters are entered:

bRequestType	bRequest	wValue	EP	size	Timeout	data
0x21	0x09	0x0200	endpoint / IF to be addressed from epcount-1	MSG_SIZE	5000 (=5ms)	the message buffer pointer
Host to Device, Type=Class, Recipient=Interface	9 = Send data?	specific	last or pre-last device #	64	5000	out_msg

The ioctl command is USBDEVFS_CONTROL.

The same constellation is used if the device is requested to send its data (is_recv = true).

For a more recent firmware and is_recv = false, the ioctl command USBDEVFS_CONTROL is not used (this tells the bus to enter the control mode), but the bulk method is used: USBDEVFS_BULK. This is astonishing, because all of the endpoints are type Interrupt, not bulk.

Anyhow, forthis purpose a different structure is used for the ioctl() (struct usbdevfs_bulktransfer) and this is also initialized differently:
The length and timeout parameters are given the same values as above. The formal parameter out_msg is also passed as a buffer pointer. For the endpoints, the firmware version is differentiated again:
For a firmware version between 1.3 and <2.0 endpoint 4 is used, otherwise (it can only be >=2.0) endpoint 3 is used.

Todo:

Since the handling of endpoints has already led to problems elsewhere, this implementation is extremely hardware-dependent and critical!
Eg. the new keyboard K95PLATINUMRGB has a version number significantly less than 2.0 - will it run with this implementation?

The ioctl() - no matter what type - returns the number of bytes sent. Now comes the usual check:

• If the return value is -1 AND the error is a timeout (ETIMEOUT), os_usbsend() will return -1 to indicate that it is probably a recoverable problem and a retry is recommended.
• For another negative value or other error identifier OR 0 bytes sent, 0 is returned as a heavy error identifier.
• In all other cases, the function returns the number of bytes sent.

If this is not the entire blocksize (MSG_SIZE bytes), an error message is issued on the standard error channel [warning "Wrote YY bytes (expected 64)"].

If DEBUG_USB_SEND is set during compilation, the number of bytes sent and their representation are logged to the error channel.

Definition at line 68 of file usb_linux.c.

References ckb_err_fn, ckb_warn_fn, usbdevice::epcount, usbdevice::fwversion, usbdevice::handle, IS_V2_OVERRIDE, and MSG_SIZE.

Referenced by _usbrecv(), and _usbsend().

                                                                                             {
    int res;
    if ((kb->fwversion >= 0x120 || IS_V2_OVERRIDE(kb)) && !is_recv){
        struct usbdevfs_bulktransfer transfer = {0};
        // FW 2.XX uses 0x03, FW 3.XX uses 0x02
        transfer.ep = (kb->fwversion >= 0x130 && kb->fwversion < 0x200) ? 4 : (kb->fwversion >= 0x300 ? 2 : 3);
        transfer.len = MSG_SIZE;
        transfer.timeout = 5000;
        transfer.data = (void*)out_msg;
        res = ioctl(kb->handle - 1, USBDEVFS_BULK, &transfer);
    } else {
        struct usbdevfs_ctrltransfer transfer = { 0x21, 0x09, 0x0200, kb->epcount - 1, MSG_SIZE, 5000, (void*)out_msg };
        res = ioctl(kb->handle - 1, USBDEVFS_CONTROL, &transfer);
    }

    if (res <= 0){
        ckb_err_fn(" %s, res = 0x%x\n", file, line, res ? strerror(errno) : "No data written", res);
        if(res == -1 && errno == ETIMEDOUT)
            return -1;
        else
            return 0;
    } else if (res != MSG_SIZE)
        ckb_warn_fn("Wrote %d bytes (expected %d)\n", file, line, res, MSG_SIZE);
#ifdef DEBUG_USB_SEND
    char converted[MSG_SIZE*3 + 1];
    for(int i=0;i<MSG_SIZE;i++)
        sprintf(&converted[i*3], "%02x ", out_msg[i]);
    ckb_warn_fn("Sent %s\n", file, line, converted);
#endif
    return res;
}

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void strtrim

(

char *

string

)

strtrim trims a string by removing leading and trailing spaces.

Parameters

string

Definition at line 523 of file usb_linux.c.

Referenced by os_setupusb().

                          {
    // Find last non-space
    char* last = string;
    for(char* c = string; *c != 0; c++){
        if(!isspace(*c))
            last = c;
    }
    last[1] = 0;
    // Find first non-space
    char* first = string;
    for(; *first != 0; first++){
        if(!isspace(*first))
            break;
    }
    if(first != string)
        memmove(string, first, last - first);
}

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static void udev_enum ( )

static

Reduce the hits of the enumeration by limiting to usb as technology and corsair as idVendor. Then filter with udev_enumerate_scan_devices () all hits.

The following call to udev_enumerate_get_list_entry() fetches the entire hitlist as udev_list_entry *.
Use udev_list_entry_foreach() to iterate through the hit set.
If both the device name exists (udev_list_entry_get_name) and the subsequent creation of a new udev_device (udev_device_new_from_syspath) is ok, the new device is added to the list with usb_add_device().

If the latter does not work, the new device is released again (udev_device_unref ()).
After the last iteration, the enumerator is released with udev_enumerate_unref ().

Definition at line 765 of file usb_linux.c.

References usb_add_device(), and V_CORSAIR_STR.

Referenced by usbmain().

                       {
    struct udev_enumerate* enumerator = udev_enumerate_new(udev);
    udev_enumerate_add_match_subsystem(enumerator, "usb");
    udev_enumerate_add_match_sysattr(enumerator, "idVendor", V_CORSAIR_STR);
    udev_enumerate_scan_devices(enumerator);
    struct udev_list_entry* devices, *dev_list_entry;
    devices = udev_enumerate_get_list_entry(enumerator);

    udev_list_entry_foreach(dev_list_entry, devices){
        const char* path = udev_list_entry_get_name(dev_list_entry);
        if(!path)
            continue;
        struct udev_device* dev = udev_device_new_from_syspath(udev, path);
        if(!dev)
            continue;
        // If the device matches a recognized device ID, open it
        if(usb_add_device(dev))
            // Release device if not
            udev_device_unref(dev);
    }
    udev_enumerate_unref(enumerator);
}

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static int usb_add_device ( struct udev_device *  dev )

static

If the device id can be found, call usbadd() with the appropriate parameters.

Parameters

dev	the functions usb_*_device get a struct udev* with the neccessary hardware-related information.

Returns

the retval of usbadd() or 1 if either vendor is not corsair or product is not mentioned in model[].

First get the idVendor via udev_device_get_sysattr_value(). If this is equal to the ID-string of corsair ("1b1c"), get the idProduct on the same way.
If we can find the model name in the model array, call usbadd() with the model number.

Todo:

So why the hell not a transformation between the string and the short presentation? Lets check if the string representation is used elsewhere.

Definition at line 713 of file usb_linux.c.

References N_MODELS, usbadd(), V_CORSAIR, and V_CORSAIR_STR.

Referenced by udev_enum(), and usbmain().

                                                  {
    const char* vendor = udev_device_get_sysattr_value(dev, "idVendor");
    if(vendor && !strcmp(vendor, V_CORSAIR_STR)){
        const char* product = udev_device_get_sysattr_value(dev, "idProduct");
        if(product){
            for(_model* model = models; model < models + N_MODELS; model++){
                if(!strcmp(product, model->name)){
                    return usbadd(dev, V_CORSAIR, model->number);
                }
            }
        }
    }
    return 1;
}

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static void usb_rm_device ( struct udev_device *  dev )

static

Parameters

dev	the functions usb_*_device get a struct udev* with the neccessary hardware-related information.

First try to find the system path of the device given in parameter dev. The index where the name is found is the same index we need to address the global keyboard array. That array holds all usbdevices.
Searching for the correct name in kbsyspath-array and closing the usb via closeusb() are protected by lock..unlock of the corresponding devmutex arraymember.

Definition at line 738 of file usb_linux.c.

References closeusb(), DEV_MAX, devmutex, kbsyspath, and keyboard.

Referenced by usbmain().

                                                  {
    // Device removed. Look for it in our list of keyboards
    const char* syspath = udev_device_get_syspath(dev);
    if(!syspath || syspath[0] == 0)
        return;
    for(int i = 1; i < DEV_MAX; i++){
        pthread_mutex_lock(devmutex + i);
        if(!strcmp(syspath, kbsyspath[i]))
            closeusb(keyboard + i);
        pthread_mutex_unlock(devmutex + i);
    }
}

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int usbadd	(	struct udev_device *	dev,
		short	vendor,
		short	product
	)

Definition at line 606 of file usb_linux.c.

References ckb_err, ckb_info, DEV_MAX, dmutex, usbdevice::handle, IS_CONNECTED, kbsyspath, keyboard, usbdevice::product, setupusb(), usbdevice::udev, and usbdevice::vendor.

Referenced by usb_add_device().

                                                                 {
    const char* path = udev_device_get_devnode(dev);
    const char* syspath = udev_device_get_syspath(dev);
    if(!path || !syspath || path[0] == 0 || syspath[0] == 0){
        ckb_err("Failed to get device path\n");
        return -1;
    }
#ifdef DEBUG
    ckb_info(">>>vendor = 0x%x, product = 0x%x, path = %s, syspath = %s\n", vendor, product, path, syspath);
#endif // DEDBUG
    // Find a free USB slot
    for(int index = 1; index < DEV_MAX; index++){
        usbdevice* kb = keyboard + index;
        if(pthread_mutex_trylock(dmutex(kb))){
            // If the mutex is locked then the device is obviously in use, so keep going
            if(!strcmp(syspath, kbsyspath[index])){
                // Make sure this existing keyboard doesn't have the same syspath (this shouldn't happen)
                return 0;
            }
            continue;
        }
        if(!IS_CONNECTED(kb)){
            // Open the sysfs device
            kb->handle = open(path, O_RDWR) + 1;
            if(kb->handle <= 0){
                ckb_err("Failed to open USB device: %s\n", strerror(errno));
                kb->handle = 0;
                pthread_mutex_unlock(dmutex(kb));
                return -1;
            } else {
                // Set up device
                kb->udev = dev;
                kb->vendor = vendor;
                kb->product = product;
                strncpy(kbsyspath[index], syspath, FILENAME_MAX);
                // Mutex remains locked
                setupusb(kb);
                return 0;
            }
        }
        pthread_mutex_unlock(dmutex(kb));
    }
    ckb_err("No free devices\n");
    return -1;
}

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static int usbclaim ( usbdevice *  kb )

static

usbclaim does claiming all EPs for the usb device gicen by kb.

Parameters

kb	THE usbdevice*

Returns

0 on success, -1 otherwise.

Claim all endpoints for a given device (remeber the decrementing of the file descriptor) via ioctl(USBDEVFS_DISCONNECT) and ioctl(USBDEVFS_CLAIMINTERFACE).

Error handling is done for the ioctl(USBDEVFS_CLAIMINTERFACE) only. If this fails, now an error message is thrown and -1 is returned. Function is called in usb_linux.c only, so it is declared as static now.

Definition at line 472 of file usb_linux.c.

References ckb_err, ckb_info, usbdevice::epcount, and usbdevice::handle.

Referenced by os_resetusb(), and os_setupusb().

                                  {
    int count = kb->epcount;
#ifdef DEBUG
    ckb_info("claiming %d endpoints\n", count);
#endif // DEBUG

    for(int i = 0; i < count; i++){
        struct usbdevfs_ioctl ctl = { i, USBDEVFS_DISCONNECT, 0 };
        ioctl(kb->handle - 1, USBDEVFS_IOCTL, &ctl);
        if(ioctl(kb->handle - 1, USBDEVFS_CLAIMINTERFACE, &i)) {
            ckb_err("Failed to claim interface %d: %s\n", i, strerror(errno));
            return -1;
        }
    }
    return 0;
}

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void usbkill

(

)

Definition at line 853 of file usb_linux.c.

Referenced by quitWithLock().

              {
    udev_unref(udev);
    udev = 0;
}

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int usbmain

(

)

Start the USB main loop. Returns program exit code when finished.

usbmain is called by main() after setting up all other stuff.

Returns

0 normally or -1 if fatal error occurs (up to now only if no new devices are available)

First check whether the uinput module is loaded by the kernel.

Todo:

Why isn't missing of uinput a fatal error?

Create the udev object with udev_new() (is a function from libudev.h) terminate -1 if error

Enumerate all currently connected devices

Todo:

lae. here the work has to go on...

Definition at line 793 of file usb_linux.c.

References ckb_fatal, ckb_warn, udev_enum(), usb_add_device(), and usb_rm_device().

Referenced by main().

             {
    // Load the uinput module (if it's not loaded already)
    if(system("modprobe uinput") != 0)
        ckb_warn("Failed to load uinput module\n");

    if(!(udev = udev_new())) {
        ckb_fatal("Failed to initialize udev in usbmain(), usb_linux.c\n");
        return -1;
    }

    udev_enum();

    // Done scanning. Enter a loop to poll for device updates
    struct udev_monitor* monitor = udev_monitor_new_from_netlink(udev, "udev");
    udev_monitor_filter_add_match_subsystem_devtype(monitor, "usb", 0);
    udev_monitor_enable_receiving(monitor);
    // Get an fd for the monitor
    int fd = udev_monitor_get_fd(monitor);
    fd_set fds;
    while(udev){
        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        // Block until an event is read
        if(select(fd + 1, &fds, 0, 0, 0) > 0 && FD_ISSET(fd, &fds)){
            struct udev_device* dev = udev_monitor_receive_device(monitor);
            if(!dev)
                continue;
            const char* action = udev_device_get_action(dev);
            if(!action){
                udev_device_unref(dev);
                continue;
            }
            // Add/remove device
            if(!strcmp(action, "add")){
                int res = usb_add_device(dev);
                if(res == 0)
                    continue;
                // If the device matched but the handle wasn't opened correctly, re-enumerate (this sometimes solves the problem)
                if(res == -1)
                    udev_enum();
            } else if(!strcmp(action, "remove"))
                usb_rm_device(dev);
            udev_device_unref(dev);
        }
    }
    udev_monitor_unref(monitor);
    return 0;
}

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static int usbunclaim ( usbdevice *  kb, int  resetting  )

static

usbunclaim do an unclaiming of the usb device gicen by kb.

Parameters

kb	THE usbdevice*
resetting	boolean flag: If resseting is true, the caller will perform a bus reset command after unclaiming the device.

Returns

always 0.

Unclaim all endpoints for a given device (remeber the decrementing of the file descriptor) via ioctl(USBDEVFS_DISCARDURB).

Afterwards - if ressetting is false - do a USBDEVFS_CONNECT for EP 0 and 1. If it is a non RGB device, connect EP 2 also. The comment mentions RGB keyboards only, but as I understand the code, this is valid also for RGB mice.

There is no error handling yet. Function is called in usb_linux.c only, so it is declared as static now.

Definition at line 419 of file usb_linux.c.

References usbdevice::epcount, FEAT_RGB, usbdevice::handle, and HAS_FEATURES.

Referenced by os_closeusb(), and os_resetusb().

                                                    {
    int handle = kb->handle - 1;
    int count = kb->epcount;
    for (int i = 0; i < count; i++) {
        ioctl(handle, USBDEVFS_RELEASEINTERFACE, &i);
    }
    // For RGB keyboards, the kernel driver should only be reconnected to interfaces 0 and 1 (HID), and only if we're not about to do a USB reset.
    // Reconnecting any of the others causes trouble.
    if (!resetting) {
        struct usbdevfs_ioctl ctl = { 0, USBDEVFS_CONNECT, 0 };
        ioctl(handle, USBDEVFS_IOCTL, &ctl);
        ctl.ifno = 1;
        ioctl(handle, USBDEVFS_IOCTL, &ctl);
        // Also reconnect iface #2 (HID) for non-RGB keyboards
        if(!HAS_FEATURES(kb, FEAT_RGB)){
            ctl.ifno = 2;
            ioctl(handle, USBDEVFS_IOCTL, &ctl);
        }
    }
    return 0;
}

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Variable Documentation

char kbsyspath[9][FILENAME_MAX]

static

Definition at line 13 of file usb_linux.c.

Referenced by os_closeusb(), usb_rm_device(), and usbadd().

_model models[]

static

Attention

when adding new hardware this file hat to be changed too.

In this structure array models[] for each device the name (the device id as string in hex without leading 0x) and its usb device id as short must be entered in this array.

Definition at line 668 of file usb_linux.c.

struct udev* udev

static

Definition at line 652 of file usb_linux.c.

pthread_t udevthread

Definition at line 655 of file usb_linux.c.

pthread_t usbthread

Todo:

These two thread vasriables seem to be unused: usbtread, udevthread

Definition at line 655 of file usb_linux.c.