xpp: fix usb "clear_halt" problem

* Don't use "usb_clear_halt" by default anymore
   - It caused problems with specific devices in the past
   - Now it cause problems with specific servers as well (64 bits, USB3)

 * Add an "XTALK_OPTIONS" environment variable to pass options:
   - Use it to implement a "use-clear-halt" boolean option that
     restore original behavior.
   - Also use it for "no-lock" option which replace the legacy
     environment variable "XUSB_NOLOCK".
This commit is contained in:
Oron Peled 2014-05-11 09:41:46 -04:00 committed by Tzafrir Cohen
parent ae02edacb4
commit ca7c04e9cb

View File

@ -61,6 +61,21 @@ struct xusb {
static void xusb_init();
/*
* XTALK_OPTIONS:
* A white-space separated list of options, read from the environment
* variable of that name. Existing options:
*
* - "use-clear-halt" -- force USB "clear_halt" operation during
* device initialization
* - "no-lock" -- prevent using global sempahore to serialize libusb
* initialization. Previously done via "XUSB_NOLOCK"
* environment variable.
*/
int xtalk_parse_options(void);
int xtalk_option_use_clear_halt(void);
int xtalk_option_no_lock(void);
void xusb_init_spec(struct xusb_spec *spec, char *name,
uint16_t vendor_id, uint16_t product_id,
int nifaces, int iface, int nep, int ep_out, int ep_in)
@ -257,13 +272,16 @@ int xusb_claim_interface(struct xusb *xusb)
xusb->iProduct,
xusb->iSerialNumber,
xusb->iInterface);
if (usb_clear_halt(xusb->handle, EP_OUT(xusb)) != 0) {
ERR("Clearing output endpoint: %s\n", usb_strerror());
return 0;
}
if (usb_clear_halt(xusb->handle, EP_IN(xusb)) != 0) {
ERR("Clearing input endpoint: %s\n", usb_strerror());
return 0;
if (xtalk_option_use_clear_halt()) {
DBG("Using clear_halt()\n");
if (usb_clear_halt(xusb->handle, EP_OUT(xusb)) != 0) {
ERR("Clearing output endpoint: %s\n", usb_strerror());
return 0;
}
if (usb_clear_halt(xusb->handle, EP_IN(xusb)) != 0) {
ERR("Clearing input endpoint: %s\n", usb_strerror());
return 0;
}
}
ret = xusb_flushread(xusb);
if (ret < 0) {
@ -857,13 +875,63 @@ static int initizalized;
static void xusb_init()
{
if (!initizalized) {
if (!getenv("XUSB_NOLOCK"))
xtalk_parse_options();
if (!xtalk_option_no_lock())
xusb_lock_usb();
usb_init();
usb_find_busses();
usb_find_devices();
initizalized = 1;
if (!getenv("XUSB_NOLOCK"))
if (!xtalk_option_no_lock())
xusb_unlock_usb();
}
}
/* XTALK option handling */
static int use_clear_halt = 0;
static int libusb_no_lock = 0;
static int xtalk_one_option(const char *option_string)
{
if (strcmp(option_string, "use-clear-halt") == 0) {
use_clear_halt = 1;
return 0;
}
if (strcmp(option_string, "no-lock") == 0) {
libusb_no_lock = 1;
return 0;
}
ERR("Unknown XTALK_OPTIONS content: '%s'\n", option_string);
return -EINVAL;
}
int xtalk_option_use_clear_halt(void)
{
return use_clear_halt;
}
int xtalk_option_no_lock(void)
{
return libusb_no_lock;
}
int xtalk_parse_options(void)
{
char *xtalk_options;
char *saveptr;
char *token;
int ret;
xtalk_options = getenv("XTALK_OPTIONS");
if (!xtalk_options)
return 0;
token = strtok_r(xtalk_options, " \t", &saveptr);
while (token) {
ret = xtalk_one_option(token);
if (ret < 0)
return ret;
token = strtok_r(NULL, " \t", &saveptr);
}
return 0;
}