[STM32F205]: st-flash broken due to introduced bug in stlink-lib/usb.c

[cdhooper]

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• Programmer/board type: STM32F4-Discovery onboard st-link, programming an external target.
• Operating system an version: Linux Fedora 41
• stlink tools version and/or git commit hash: commit eecfe05
• stlink commandline tool name: st-flash
• Target chip (and board, if applicable): [enter here] (e.g STM32F205RET6 (Custom board)

Commandline output:

stutils/build/Release/bin/st-flash  --reset write objs/fw.bin 0x08000000
st-flash 1.8.0-90-geecfe05
2025-02-03T00:37:14 INFO common_legacy.c: STM32F2xx: 128 KiB SRAM, 512 KiB flash in at least 128 KiB pages.
file objs/fw.bin md5 checksum: 3de9c24d5e6066922a7d1de95ba83724, stlink checksum: 0x007ae944
2025-02-03T00:37:14 INFO common_flash.c: Attempting to write 84720 (0x14af0) bytes to stm32 address: 134217728 (0x8000000)
EraseFlash - Sector:0x0 Size:0x4000 -> Flash page at 0x8000000 erased (size: 0x4000)
EraseFlash - Sector:0x1 Size:0x4000 -> Flash page at 0x8004000 erased (size: 0x4000)
EraseFlash - Sector:0x2 Size:0x4000 -> Flash page at 0x8008000 erased (size: 0x4000)
EraseFlash - Sector:0x3 Size:0x4000 -> Flash page at 0x800c000 erased (size: 0x4000)
EraseFlash - Sector:0x4 Size:0x10000 -> Flash page at 0x8010000 erased (size: 0x10000)

2025-02-03T00:37:15 INFO flash_loader.c: Starting Flash write for F2/F4/F7/L4
2025-02-03T00:37:15 INFO flash_loader.c: Successfully loaded flash loader in sram
2025-02-03T00:37:15 INFO flash_loader.c: Clear DFSR
2025-02-03T00:37:15 INFO flash_loader.c: Clear CFSR
2025-02-03T00:37:15 INFO flash_loader.c: Clear HFSR
2025-02-03T00:37:15 INFO flash_loader.c: enabling 32-bit flash writes
2025-02-03T00:37:15 INFO common_legacy.c: Go to Thumb mode
2025-02-03T00:37:16 ERROR flash_loader.c: Flash loader write error
2025-02-03T00:37:16 WARN flash_loader.c: Loader state: R2 0x0 R15 0x20000024
2025-02-03T00:37:16 WARN flash_loader.c: MCU state: DHCSR 0x3000B DFSR 0x2 CFSR 0x0 HFSR 0x0
2025-02-03T00:37:16 ERROR flash_loader.c: stlink_flash_loader_run(0x8000000) failed! == -1
2025-02-03T00:37:16 INFO common_legacy.c: Go to Thumb mode
stlink_fwrite_flash() == -1
make: *** [Makefile:325: just-flash] Error 255

Expected/description:

Due to a recent change in src/stlink-lib/usb.c, register reads are attempted as register writes.

The following patch should resolve the issue:

diff --git a/src/stlink-lib/usb.c b/src/stlink-lib/usb.c
index 8ad6cdd..3685e92 100644
--- a/src/stlink-lib/usb.c
+++ b/src/stlink-lib/usb.c
@@ -808,12 +808,12 @@ int32_t _stlink_usb_read_reg(stlink_t *sl, int32_t r_idx, struct stlink_reg *reg
     cmd[i++] = STLINK_DEBUG_COMMAND;
 
     if(sl->version.jtag_api == STLINK_JTAG_API_V1) {
-        cmd[i++] = STLINK_DEBUG_APIV1_WRITEREG;
+        cmd[i++] = STLINK_DEBUG_APIV1_READREG;
     } else if(sl->version.jtag_api == STLINK_JTAG_API_V2) {
-        cmd[i++] = STLINK_DEBUG_APIV2_WRITEREG;
+        cmd[i++] = STLINK_DEBUG_APIV2_READREG;
     } else {
         // STLINK_JTAG_API_V3
-        cmd[i++] = STLINK_DEBUG_APIV2_WRITEREG;
+        cmd[i++] = STLINK_DEBUG_APIV2_READREG;
     }
 
     cmd[i++] = (uint8_t) r_idx;