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authorNico Huber <nico.huber@secunet.com>2016-02-18 21:42:49 +0000
committerStefan Tauner <stefan.tauner@alumni.tuwien.ac.at>2016-02-18 21:42:49 +0000
commitd99a2bd049264cc327c6ef772d1ae9c11697a29e (patch)
treee1ec42d9aebfb5615ddedbbc0c141562610b7fd5
parentc05900f3dccddb5ffb4f1c9557b2ffc81683ec44 (diff)
downloadast2050-flashrom-d99a2bd049264cc327c6ef772d1ae9c11697a29e.zip
ast2050-flashrom-d99a2bd049264cc327c6ef772d1ae9c11697a29e.tar.gz
dediprog: port to libusb1 and use asynchronous bulk transfers for reading
This patch is based on Nico Huber's original version that was rebased by David Hendricks for Chromium OS in Change-Id: I84384b9d8ed53911657cf2293733531a6e11fd23 Corresponding to flashrom svn r1929. Signed-off-by: Nico Huber <nico.huber@secunet.com> Signed-off-by: David Hendricks <dhendrix@chromium.org> Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at> Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
-rw-r--r--Makefile2
-rw-r--r--dediprog.c284
-rw-r--r--flashrom.8.tmpl6
-rw-r--r--pickit2_spi.c5
4 files changed, 203 insertions, 94 deletions
diff --git a/Makefile b/Makefile
index 11888d5..dc2f196 100644
--- a/Makefile
+++ b/Makefile
@@ -742,7 +742,7 @@ endif
ifeq ($(CONFIG_DEDIPROG), yes)
FEATURE_CFLAGS += -D'CONFIG_DEDIPROG=1'
PROGRAMMER_OBJS += dediprog.o
-NEED_LIBUSB0 += CONFIG_DEDIPROG
+NEED_LIBUSB1 += CONFIG_DEDIPROG
endif
ifeq ($(CONFIG_SATAMV), yes)
diff --git a/dediprog.c b/dediprog.c
index bb1ac53..454a72d 100644
--- a/dediprog.c
+++ b/dediprog.c
@@ -26,25 +26,28 @@
#include <string.h>
#include <limits.h>
#include <errno.h>
-
-#if IS_WINDOWS
-#include <lusb0_usb.h>
-#else
-#include <usb.h>
-#endif
-
+#include <libusb.h>
#include "flash.h"
#include "chipdrivers.h"
#include "programmer.h"
#include "spi.h"
+/* LIBUSB_CALL ensures the right calling conventions on libusb callbacks.
+ * However, the macro is not defined everywhere. m(
+ */
+#ifndef LIBUSB_CALL
+#define LIBUSB_CALL
+#endif
+
#define FIRMWARE_VERSION(x,y,z) ((x << 16) | (y << 8) | z)
#define DEFAULT_TIMEOUT 3000
-#define REQTYPE_OTHER_OUT (USB_ENDPOINT_OUT | USB_TYPE_VENDOR | USB_RECIP_OTHER) /* 0x43 */
-#define REQTYPE_OTHER_IN (USB_ENDPOINT_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER) /* 0xC3 */
-#define REQTYPE_EP_OUT (USB_ENDPOINT_OUT | USB_TYPE_VENDOR | USB_RECIP_ENDPOINT) /* 0x42 */
-#define REQTYPE_EP_IN (USB_ENDPOINT_IN | USB_TYPE_VENDOR | USB_RECIP_ENDPOINT) /* 0xC2 */
-static usb_dev_handle *dediprog_handle;
+#define DEDIPROG_ASYNC_TRANSFERS 8 /* at most 8 asynchronous transfers */
+#define REQTYPE_OTHER_OUT (LIBUSB_ENDPOINT_IN | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_OTHER) /* 0x43 */
+#define REQTYPE_OTHER_IN (LIBUSB_ENDPOINT_IN | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_OTHER) /* 0xC3 */
+#define REQTYPE_EP_OUT (LIBUSB_ENDPOINT_OUT | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_ENDPOINT) /* 0x42 */
+#define REQTYPE_EP_IN (LIBUSB_ENDPOINT_IN | LIBUSB_REQUEST_TYPE_VENDOR | LIBUSB_RECIPIENT_ENDPOINT) /* 0xC2 */
+struct libusb_context *usb_ctx;
+static libusb_device_handle *dediprog_handle;
static int dediprog_in_endpoint;
static int dediprog_out_endpoint;
@@ -144,6 +147,22 @@ enum dediprog_standalone_mode {
static int dediprog_firmwareversion = FIRMWARE_VERSION(0, 0, 0);
enum dediprog_devtype dediprog_devicetype = DEV_UNKNOWN;
+#if defined(LIBUSB_MAJOR) && defined(LIBUSB_MINOR) && defined(LIBUSB_MICRO) && \
+ LIBUSB_MAJOR <= 1 && LIBUSB_MINOR == 0 && LIBUSB_MICRO < 9
+/* Quick and dirty replacement for missing libusb_error_name in libusb < 1.0.9 */
+const char * LIBUSB_CALL libusb_error_name(int error_code)
+{
+ if (error_code >= INT16_MIN && error_code <= INT16_MAX) {
+ /* 18 chars for text, rest for number (16 b should be enough), sign, nullbyte. */
+ static char my_libusb_error[18 + 5 + 2];
+ sprintf(my_libusb_error, "libusb error code %i", error_code);
+ return my_libusb_error;
+ } else {
+ return "UNKNOWN";
+ }
+}
+#endif
+
/* Returns true if firmware (and thus hardware) supports the "new" protocol */
static bool is_new_prot(void)
{
@@ -157,35 +176,93 @@ static bool is_new_prot(void)
}
}
+struct dediprog_transfer_status {
+ int error; /* OK if 0, ERROR else */
+ unsigned int queued_idx;
+ unsigned int finished_idx;
+};
+
+static void LIBUSB_CALL dediprog_bulk_read_cb(struct libusb_transfer *const transfer)
+{
+ struct dediprog_transfer_status *const status = (struct dediprog_transfer_status *)transfer->user_data;
+ if (transfer->status != LIBUSB_TRANSFER_COMPLETED) {
+ status->error = 1;
+ msg_perr("SPI bulk read failed!\n");
+ }
+ ++status->finished_idx;
+}
+
+static int dediprog_bulk_read_poll(const struct dediprog_transfer_status *const status, const int finish)
+{
+ if (status->finished_idx >= status->queued_idx)
+ return 0;
+
+ do {
+ struct timeval timeout = { 10, 0 };
+ const int ret = libusb_handle_events_timeout(usb_ctx, &timeout);
+ if (ret < 0) {
+ msg_perr("Polling read events failed: %i %s!\n", ret, libusb_error_name(ret));
+ return 1;
+ }
+ } while (finish && (status->finished_idx < status->queued_idx));
+ return 0;
+}
+
static int dediprog_read(enum dediprog_cmds cmd, unsigned int value, unsigned int idx, uint8_t *bytes, size_t size)
{
- return usb_control_msg(dediprog_handle, REQTYPE_EP_IN, cmd, value, idx,
- (char *)bytes, size, DEFAULT_TIMEOUT);
+ return libusb_control_transfer(dediprog_handle, REQTYPE_EP_IN, cmd, value, idx,
+ (unsigned char *)bytes, size, DEFAULT_TIMEOUT);
}
static int dediprog_write(enum dediprog_cmds cmd, unsigned int value, unsigned int idx, const uint8_t *bytes, size_t size)
{
- return usb_control_msg(dediprog_handle, REQTYPE_EP_OUT, cmd, value, idx,
- (char *)bytes, size, DEFAULT_TIMEOUT);
+ return libusb_control_transfer(dediprog_handle, REQTYPE_EP_OUT, cmd, value, idx,
+ (unsigned char *)bytes, size, DEFAULT_TIMEOUT);
}
-/* Might be useful for other USB devices as well. static for now. */
-/* device parameter allows user to specify one device of multiple installed */
-static struct usb_device *get_device_by_vid_pid(uint16_t vid, uint16_t pid, unsigned int device)
+
+/* Might be useful for other USB devices as well. static for now.
+ * num parameter allows user to specify one device of multiple installed */
+static struct libusb_device_handle *get_device_by_vid_pid_number(uint16_t vid, uint16_t pid, unsigned int num)
{
- struct usb_bus *bus;
- struct usb_device *dev;
-
- for (bus = usb_get_busses(); bus; bus = bus->next)
- for (dev = bus->devices; dev; dev = dev->next)
- if ((dev->descriptor.idVendor == vid) &&
- (dev->descriptor.idProduct == pid)) {
- if (device == 0)
- return dev;
- device--;
+ struct libusb_device **list;
+ ssize_t count = libusb_get_device_list(usb_ctx, &list);
+ if (count < 0) {
+ msg_perr("Getting the USB device list failed (%s)!\n", libusb_error_name(count));
+ return NULL;
+ }
+
+ struct libusb_device_handle *handle = NULL;
+ ssize_t i = 0;
+ for (i = 0; i < count; i++) {
+ struct libusb_device *dev = list[i];
+ struct libusb_device_descriptor desc;
+ int err = libusb_get_device_descriptor(dev, &desc);
+ if (err != 0) {
+ msg_perr("Reading the USB device descriptor failed (%s)!\n", libusb_error_name(err));
+ libusb_free_device_list(list, 1);
+ return NULL;
+ }
+ if ((desc.idVendor == vid) && (desc.idProduct == pid)) {
+ msg_pdbg("Found USB device %04"PRIx16":%04"PRIx16" at address %d-%d.\n",
+ desc.idVendor, desc.idProduct,
+ libusb_get_bus_number(dev), libusb_get_device_address(dev));
+ if (num == 0) {
+ err = libusb_open(dev, &handle);
+ if (err != 0) {
+ msg_perr("Opening the USB device failed (%s)!\n",
+ libusb_error_name(err));
+ libusb_free_device_list(list, 1);
+ return NULL;
+ }
+ break;
}
+ num--;
+ }
+ }
+ libusb_free_device_list(list, 1);
- return NULL;
+ return handle;
}
/* This function sets the GPIOs connected to the LEDs as well as IO1-IO4. */
@@ -219,7 +296,7 @@ static int dediprog_set_leds(int leds)
}
if (ret != 0x0) {
- msg_perr("Command Set LED 0x%x failed (%s)!\n", leds, usb_strerror());
+ msg_perr("Command Set LED 0x%x failed (%s)!\n", leds, libusb_error_name(ret));
return 1;
}
@@ -332,10 +409,16 @@ static void fill_rw_cmd_payload(uint8_t *data_packet, unsigned int count, uint8_
*/
static int dediprog_spi_bulk_read(struct flashctx *flash, uint8_t *buf, unsigned int start, unsigned int len)
{
+ int err = 1;
+
/* chunksize must be 512, other sizes will NOT work at all. */
const unsigned int chunksize = 512;
const unsigned int count = len / chunksize;
+ struct dediprog_transfer_status status = { 0, 0, 0 };
+ struct libusb_transfer *transfers[DEDIPROG_ASYNC_TRANSFERS] = { NULL, };
+ struct libusb_transfer *transfer;
+
if ((start % chunksize) || (len % chunksize)) {
msg_perr("%s: Unaligned start=%i, len=%i! Please report a bug at flashrom@flashrom.org\n",
__func__, start, len);
@@ -352,23 +435,59 @@ static int dediprog_spi_bulk_read(struct flashctx *flash, uint8_t *buf, unsigned
int ret = dediprog_write(CMD_READ, value, idx, data_packet, sizeof(data_packet));
if (ret != sizeof(data_packet)) {
- msg_perr("Command Read SPI Bulk failed, %i %s!\n", ret, usb_strerror());
+ msg_perr("Command Read SPI Bulk failed, %i %s!\n", ret, libusb_error_name(ret));
return 1;
}
+ /*
+ * Ring buffer of bulk transfers.
+ * Poll until at least one transfer is ready,
+ * schedule next transfers until buffer is full.
+ */
+
+ /* Allocate bulk transfers. */
unsigned int i;
- for (i = 0; i < count; i++) {
- ret = usb_bulk_read(dediprog_handle, 0x80 | dediprog_in_endpoint,
- (char *)buf + i * chunksize, chunksize,
- DEFAULT_TIMEOUT);
- if (ret != chunksize) {
- msg_perr("SPI bulk read %i failed, expected %i, got %i %s!\n",
- i, chunksize, ret, usb_strerror());
- return 1;
+ for (i = 0; i < min(DEDIPROG_ASYNC_TRANSFERS, count); ++i) {
+ transfers[i] = libusb_alloc_transfer(0);
+ if (!transfers[i]) {
+ msg_perr("Allocating libusb transfer %i failed: %s!\n", i, libusb_error_name(ret));
+ goto err_free;
+ }
+ }
+
+ /* Now transfer requested chunks using libusb's asynchronous interface. */
+ while (!status.error && (status.queued_idx < count)) {
+ while ((status.queued_idx - status.finished_idx) < DEDIPROG_ASYNC_TRANSFERS) {
+ transfer = transfers[status.queued_idx % DEDIPROG_ASYNC_TRANSFERS];
+ libusb_fill_bulk_transfer(transfer, dediprog_handle, 0x80 | dediprog_in_endpoint,
+ (unsigned char *)buf + status.queued_idx * chunksize, chunksize,
+ dediprog_bulk_read_cb, &status, DEFAULT_TIMEOUT);
+ transfer->flags |= LIBUSB_TRANSFER_SHORT_NOT_OK;
+ ret = libusb_submit_transfer(transfer);
+ if (ret < 0) {
+ msg_perr("Submitting SPI bulk read %i failed: %s!\n",
+ status.queued_idx, libusb_error_name(ret));
+ goto err_free;
+ }
+ ++status.queued_idx;
}
+ if (dediprog_bulk_read_poll(&status, 0))
+ goto err_free;
}
-
- return 0;
+ /* Wait for transfers to finish. */
+ if (dediprog_bulk_read_poll(&status, 1))
+ goto err_free;
+ /* Check if everything has been transmitted. */
+ if ((status.finished_idx < count) || status.error)
+ goto err_free;
+
+ err = 0;
+
+err_free:
+ dediprog_bulk_read_poll(&status, 1);
+ for (i = 0; i < DEDIPROG_ASYNC_TRANSFERS; ++i)
+ if (transfers[i]) libusb_free_transfer(transfers[i]);
+ return err;
}
static int dediprog_spi_read(struct flashctx *flash, uint8_t *buf, unsigned int start, unsigned int len)
@@ -455,19 +574,20 @@ static int dediprog_spi_bulk_write(struct flashctx *flash, const uint8_t *buf, u
fill_rw_cmd_payload(data_packet, count, dedi_spi_cmd, &value, &idx, start);
int ret = dediprog_write(CMD_WRITE, value, idx, data_packet, sizeof(data_packet));
if (ret != sizeof(data_packet)) {
- msg_perr("Command Write SPI Bulk failed, %i %s!\n", ret,
- usb_strerror());
+ msg_perr("Command Write SPI Bulk failed, %s!\n", libusb_error_name(ret));
return 1;
}
unsigned int i;
for (i = 0; i < count; i++) {
- char usbbuf[512];
+ unsigned char usbbuf[512];
memcpy(usbbuf, buf + i * chunksize, chunksize);
memset(usbbuf + chunksize, 0xff, sizeof(usbbuf) - chunksize); // fill up with 0xFF
- ret = usb_bulk_write(dediprog_handle, dediprog_out_endpoint, usbbuf, 512, DEFAULT_TIMEOUT);
- if (ret != 512) {
- msg_perr("SPI bulk write failed, expected %i, got %i %s!\n", 512, ret, usb_strerror());
+ int transferred;
+ ret = libusb_bulk_transfer(dediprog_handle, dediprog_out_endpoint, usbbuf, 512, &transferred,
+ DEFAULT_TIMEOUT);
+ if ((ret < 0) || (transferred != 512)) {
+ msg_perr("SPI bulk write failed, expected %i, got %s!\n", 512, libusb_error_name(ret));
return 1;
}
}
@@ -568,7 +688,7 @@ static int dediprog_spi_send_command(struct flashctx *flash,
ret = dediprog_write(CMD_TRANSCEIVE, value, idx, writearr, writecnt);
if (ret != writecnt) {
msg_perr("Send SPI failed, expected %i, got %i %s!\n",
- writecnt, ret, usb_strerror());
+ writecnt, ret, libusb_error_name(ret));
return 1;
}
if (readcnt == 0) // If we don't require a response, we are done here
@@ -584,7 +704,7 @@ static int dediprog_spi_send_command(struct flashctx *flash,
}
ret = dediprog_read(CMD_TRANSCEIVE, value, idx, readarr, readcnt);
if (ret != readcnt) {
- msg_perr("Receive SPI failed, expected %i, got %i %s!\n", readcnt, ret, usb_strerror());
+ msg_perr("Receive SPI failed, expected %i, got %i %s!\n", readcnt, ret, libusb_error_name(ret));
return 1;
}
return 0;
@@ -640,11 +760,11 @@ static int dediprog_check_devicestring(void)
* than V6.0.0. Newer programmers (including all SF600s) do not support it. */
static int dediprog_set_voltage(void)
{
- char buf[1] = {0};
- int ret = usb_control_msg(dediprog_handle, REQTYPE_OTHER_IN, CMD_SET_VOLTAGE, 0x0, 0x0,
+ unsigned char buf[1] = {0};
+ int ret = libusb_control_transfer(dediprog_handle, REQTYPE_OTHER_IN, CMD_SET_VOLTAGE, 0x0, 0x0,
buf, 0x1, DEFAULT_TIMEOUT);
if (ret < 0) {
- msg_perr("Command Set Voltage failed (%s)!\n", usb_strerror());
+ msg_perr("Command Set Voltage failed (%s)!\n", libusb_error_name(ret));
return 1;
}
if ((ret != 1) || (buf[0] != 0x6f)) {
@@ -665,7 +785,7 @@ static int dediprog_standalone_mode(void)
msg_pdbg2("Disabling standalone mode.\n");
ret = dediprog_write(CMD_SET_STANDALONE, LEAVE_STANDALONE_MODE, 0, NULL, 0);
if (ret) {
- msg_perr("Failed to disable standalone mode: %s\n", usb_strerror());
+ msg_perr("Failed to disable standalone mode: %s\n", libusb_error_name(ret));
return 1;
}
@@ -685,7 +805,7 @@ static int dediprog_command_b(void)
ret = usb_control_msg(dediprog_handle, REQTYPE_OTHER_IN, 0x7, 0x0, 0xef00,
buf, 0x3, DEFAULT_TIMEOUT);
if (ret < 0) {
- msg_perr("Command B failed (%s)!\n", usb_strerror());
+ msg_perr("Command B failed (%s)!\n", libusb_error_name(ret));
return 1;
}
if ((ret != 0x3) || (buf[0] != 0xff) || (buf[1] != 0xff) ||
@@ -700,10 +820,9 @@ static int dediprog_command_b(void)
static int set_target_flash(enum dediprog_target target)
{
- int ret = usb_control_msg(dediprog_handle, REQTYPE_EP_OUT, CMD_SET_TARGET, target, 0,
- NULL, 0, DEFAULT_TIMEOUT);
+ int ret = dediprog_write(CMD_SET_TARGET, target, 0, NULL, 0);
if (ret != 0) {
- msg_perr("set_target_flash failed (%s)!\n", usb_strerror());
+ msg_perr("set_target_flash failed (%s)!\n", libusb_error_name(ret));
return 1;
}
return 0;
@@ -717,7 +836,7 @@ static bool dediprog_get_button(void)
int ret = usb_control_msg(dediprog_handle, REQTYPE_EP_IN, CMD_GET_BUTTON, 0, 0,
buf, 0x1, DEFAULT_TIMEOUT);
if (ret != 0) {
- msg_perr("Could not get button state (%s)!\n", usb_strerror());
+ msg_perr("Could not get button state (%s)!\n", libusb_error_name(ret));
return 1;
}
return buf[0] != 1;
@@ -792,20 +911,18 @@ static int dediprog_shutdown(void *data)
if (dediprog_set_spi_voltage(0x0))
return 1;
- if (usb_release_interface(dediprog_handle, 0)) {
+ if (libusb_release_interface(dediprog_handle, 0)) {
msg_perr("Could not release USB interface!\n");
return 1;
}
- if (usb_close(dediprog_handle)) {
- msg_perr("Could not close USB device!\n");
- return 1;
- }
+ libusb_close(dediprog_handle);
+ libusb_exit(usb_ctx);
+
return 0;
}
int dediprog_init(void)
{
- struct usb_device *dev;
char *voltage, *device, *spispeed, *target_str;
int spispeed_idx = 1;
int millivolt = 3500;
@@ -887,35 +1004,29 @@ int dediprog_init(void)
free(target_str);
/* Here comes the USB stuff. */
- usb_init();
- usb_find_busses();
- usb_find_devices();
- dev = get_device_by_vid_pid(0x0483, 0xdada, (unsigned int) usedevice);
- if (!dev) {
- msg_perr("Could not find a Dediprog SF100 on USB!\n");
+ libusb_init(&usb_ctx);
+ if (!usb_ctx) {
+ msg_perr("Could not initialize libusb!\n");
return 1;
}
- msg_pdbg("Found USB device (%04x:%04x).\n",
- dev->descriptor.idVendor, dev->descriptor.idProduct);
- dediprog_handle = usb_open(dev);
+ dediprog_handle = get_device_by_vid_pid_number(0x0483, 0xdada, (unsigned int) usedevice);
if (!dediprog_handle) {
- msg_perr("Could not find a Dediprog programmer on USB: %s\n", usb_strerror());
+ msg_perr("Could not find a Dediprog programmer on USB.\n");
+ libusb_exit(usb_ctx);
return 1;
}
- ret = usb_set_configuration(dediprog_handle, 1);
- if (ret < 0) {
- msg_perr("Could not set USB device configuration: %i %s\n",
- ret, usb_strerror());
- if (usb_close(dediprog_handle))
- msg_perr("Could not close USB device!\n");
+ ret = libusb_set_configuration(dediprog_handle, 1);
+ if (ret != 0) {
+ msg_perr("Could not set USB device configuration: %i %s\n", ret, libusb_error_name(ret));
+ libusb_close(dediprog_handle);
+ libusb_exit(usb_ctx);
return 1;
}
- ret = usb_claim_interface(dediprog_handle, 0);
+ ret = libusb_claim_interface(dediprog_handle, 0);
if (ret < 0) {
- msg_perr("Could not claim USB device interface %i: %i %s\n",
- 0, ret, usb_strerror());
- if (usb_close(dediprog_handle))
- msg_perr("Could not close USB device!\n");
+ msg_perr("Could not claim USB device interface %i: %i %s\n", 0, ret, libusb_error_name(ret));
+ libusb_close(dediprog_handle);
+ libusb_exit(usb_ctx);
return 1;
}
@@ -959,4 +1070,3 @@ int dediprog_init(void)
return 0;
}
-
diff --git a/flashrom.8.tmpl b/flashrom.8.tmpl
index fdc612e..9d8fcc3 100644
--- a/flashrom.8.tmpl
+++ b/flashrom.8.tmpl
@@ -1082,11 +1082,11 @@ needs TCP access to the network or userspace access to a serial port.
.B buspirate_spi
needs userspace access to a serial port.
.sp
-.BR dediprog ", " ft2232_spi ", " usbblaster_spi " and " pickit2_spi
+.BR ft2232_spi ", " usbblaster_spi " and " pickit2_spi
need access to the respective USB device via libusb API version 0.1.
.sp
-.BR ch341a_spi
-needs access to the respective USB device via libusb API version 1.0.
+.BR ch341a_spi " and " dediprog
+need access to the respective USB device via libusb API version 1.0.
.sp
.B dummy
needs no access permissions at all.
diff --git a/pickit2_spi.c b/pickit2_spi.c
index fb03b02..e5f7bed 100644
--- a/pickit2_spi.c
+++ b/pickit2_spi.c
@@ -95,9 +95,8 @@ static usb_dev_handle *pickit2_handle;
#define SCR_VDD_OFF 0xFE
#define SCR_VDD_ON 0xFF
-/* Copied from dediprog.c */
-/* Might be useful for other USB devices as well. static for now. */
-/* device parameter allows user to specify one device of multiple installed */
+/* Might be useful for other USB devices as well. static for now.
+ * device parameter allows user to specify one device of multiple installed */
static struct usb_device *get_device_by_vid_pid(uint16_t vid, uint16_t pid, unsigned int device)
{
struct usb_bus *bus;
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