Change in flashrom[master]: bitbang-spi.c: support clock polarity and phase

[Xiang Wang (Code Review)]

Attention is currently required from: Stefan Reinauer, Edward O'Callaghan, Angel Pons.
Xiang Wang has posted comments on this change. ( https://review.coreboot.org/c/flashrom/+/49255 )

Change subject: bitbang-spi.c: support clock polarity and phase
......................................................................

Patch Set 7:

(9 comments)

Commit Message:

https://review.coreboot.org/c/flashrom/+/49255/comment/4bcc8490_9031c6be 
PS1, Line 8:
> Hi Xiang, So I think what Angel and I are saying here is that the rational should be explained in mo […]

Sorry I misunderstood.

File bitbang_spi.c:

https://review.coreboot.org/c/flashrom/+/49255/comment/b3eba98a_c24212aa 
PS6, Line 52: 	}
            : 
            : 	master->set_sck(sck);
            : 	master->set_mosi(mosi);
            : }
> spurious changes?

This is the spi timing requirement, the mosi change should be before the sck change when sending data

https://review.coreboot.org/c/flashrom/+/49255/comment/cd6f1a5e_6c580f5d 
PS6, Line 62:
> ditto

Done

https://review.coreboot.org/c/flashrom/+/49255/comment/679cf963_1ffa11b2 
PS6, Line 89: for (int i = 0; i < 8; i++) {
> Leave style changes to another commit and out of the meat of this one, it gets in the way of reviewi […]

Done

https://review.coreboot.org/c/flashrom/+/49255/comment/e4f09580_9aea642e 
PS6, Line 90: ret = ret << 1;
> same here, just leave as `ret <<= 1;` in this commit

Done

https://review.coreboot.org/c/flashrom/+/49255/comment/5e82946b_2f1959f2 
PS6, Line 107: for (int i = 0; i < 8; i++) {
> ditto

Done

https://review.coreboot.org/c/flashrom/+/49255/comment/b25fe90f_74e596fd 
PS6, Line 119: val = val << 1;
> ditto

Done

https://review.coreboot.org/c/flashrom/+/49255/comment/d19d7b79_d46dc670 
PS6, Line 136: programmer_delay(master->half_period);
             : 	bitbang_spi_set_cs(master, 0);
             : 	programmer_delay(master->half_period);
             :
> this feels like its own little patch.

move to https://review.coreboot.org/c/flashrom/+/49262

https://review.coreboot.org/c/flashrom/+/49255/comment/b6c1dbdb_314857fb 
PS6, Line 186: 	char *mode = extract_programmer_param("mode");
             : 	if (mode) {
             : 		if (strlen(mode)) {
             : 			char *endptr;
             : 			int v = strtol(mode, &endptr, 0);
             : 			if (mode == endptr || v > 3 || v < 0) {
             : 				msg_perr("bitbang spi only work with mode 0-3\n");
             : 				free(mode);
             : 				return ERROR_FLASHROM_BUG;
             : 			}
             : 			cpol = (v >> 1) & 1;
             : 			cpha = (v >> 0) & 1;
             : 		}
             : 		free(mode);
             : 	}
> static parse_mode function that takes `(&int, &int)` as a type ?

Done