drivers/cmsis-dap: improve error checking

[fw/openocd] / src / jtag / drivers / bitbang.h

diff --git a/src/jtag/drivers/bitbang.h b/src/jtag/drivers/bitbang.h
index c5b44bfd54d16fa333f281dc5a5f76a5f6d0d855..bc2c506bc71878d8a6c5f4ba0257749b6e83c3e6 100644 (file)
--- a/src/jtag/drivers/bitbang.h
+++ b/src/jtag/drivers/bitbang.h
@@ -24,25 +24,53 @@
 
 #include <jtag/swd.h>
 
+typedef enum {
+       BB_LOW,
+       BB_HIGH,
+       BB_ERROR
+} bb_value_t;
+
+/** Low level callbacks (for bitbang).
+ *
+ * Either read(), or sample() and read_sample() must be implemented.
+ *
+ * The sample functions allow an interface to batch a number of writes and
+ * sample requests together. Not waiting for a value to come back can greatly
+ * increase throughput. */
 struct bitbang_interface {
-       /* low level callbacks (for bitbang)
-        */
-       int (*read)(void);
-       void (*write)(int tck, int tms, int tdi);
-       void (*reset)(int trst, int srst);
-       void (*blink)(int on);
+       /** Sample TDO and return the value. */
+       bb_value_t (*read)(void);
+
+       /** The number of TDO samples that can be buffered up before the caller has
+        * to call read_sample. */
+       size_t buf_size;
+
+       /** Sample TDO and put the result in a buffer. */
+       int (*sample)(void);
+
+       /** Return the next unread value from the buffer. */
+       bb_value_t (*read_sample)(void);
+
+       /** Set TCK, TMS, and TDI to the given values. */
+       int (*write)(int tck, int tms, int tdi);
+
+       /** Blink led (optional). */
+       int (*blink)(int on);
+
+       /** Sample SWDIO and return the value. */
        int (*swdio_read)(void);
+
+       /** Set direction of SWDIO. */
        void (*swdio_drive)(bool on);
-};
 
-const struct swd_driver bitbang_swd;
+       /** Set SWCLK and SWDIO to the given value. */
+       int (*swd_write)(int swclk, int swdio);
+};
 
-extern bool swd_mode;
+extern const struct swd_driver bitbang_swd;
 
 int bitbang_execute_queue(void);
 
 extern struct bitbang_interface *bitbang_interface;
-void bitbang_switch_to_swd(void);
-int bitbang_swd_switch_seq(enum swd_special_seq seq);
 
 #endif /* OPENOCD_JTAG_DRIVERS_BITBANG_H */