[S] Change in flashrom[master]: ch341a_spi: detach/attach kernel driver explicitly

[Thomas Heijligen (Code Review)]

Thomas Heijligen has submitted this change. ( https://review.coreboot.org/c/flashrom/+/67071 )

(

3 is the latest approved patch-set.
No files were changed between the latest approved patch-set and the submitted one.
 )Change subject: ch341a_spi: detach/attach kernel driver explicitly
......................................................................

ch341a_spi: detach/attach kernel driver explicitly

Use `libusb_detach_kernel_driver` and `libusb_attach_kernel_driver`
instead of `libusb_auto_detach_kernel_driver` to be compatible with
older libusb versions without changing the behavior.

TEST=Build with libusb >= 1.0.9
     Read spi flash with ch341a programmer on linux

Change-Id: Ia649722e64cc97c6b689dd3b764e5c9145959f92
Signed-off-by: Thomas Heijligen 
Reviewed-on: https://review.coreboot.org/c/flashrom/+/67071
Tested-by: build bot (Jenkins) 
Reviewed-by: Edward O'Callaghan 
---
M ch341a_spi.c
1 file changed, 26 insertions(+), 5 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Edward O'Callaghan: Looks good to me, approved

diff --git a/ch341a_spi.c b/ch341a_spi.c
index 78b9cee..48c6420 100644
--- a/ch341a_spi.c
+++ b/ch341a_spi.c
@@ -398,6 +398,7 @@
    	transfer_ins[i] = NULL;
    }
    libusb_release_interface(handle, 0);
+	libusb_attach_kernel_driver(handle, 0);
    libusb_close(handle);
    libusb_exit(NULL);
    handle = NULL;
@@ -448,11 +449,10 @@
    	return -1;
    }

-	ret = libusb_set_auto_detach_kernel_driver(handle, 1);
-	if (ret != 0) {
-		msg_pwarn("Platform does not support detaching of USB kernel drivers.\n"
-			  "If an unsupported driver is active, claiming the interface may fail.\n");
-	}
+	ret = libusb_detach_kernel_driver(handle, 0);
+	if (ret != 0 && ret != LIBUSB_ERROR_NOT_FOUND)
+		msg_pwarn("Cannot detach the existing USB driver. Claiming the interface may fail. %s\n",
+			libusb_error_name(ret));

ret = libusb_claim_interface(handle, 0);
    if (ret != 0) {
@@ -514,6 +514,7 @@
 release_interface:
    libusb_release_interface(handle, 0);
 close_handle:
+	libusb_attach_kernel_driver(handle, 0);
    libusb_close(handle);
    handle = NULL;
    return -1;