ads8688: fixes

- read_auto: disable readout after auto_sel
- gains: single word buffer for a single frame
- `read_cmd`: initialize `->nbuf`
- `adc/status`

ads8688.c

@@ -105,13 +105,16 @@ static int read_auto_cb(struct ads8688_control *c)
 				ads8688_readings(c, cc, i++, ii);
 		return alldone_cb(c);
 	}
-	if (c->frame == 0)
+	unsigned int n = c->nbuf;
+	if (c->frame == 0) {
+		n = 0;
 		c->frame = 0x0300 | c->channels & 0xff;
-	else if ((c->frame & 0xff) == 0x03) 
+	}
+	else if ((c->frame & 0xff) == 0x03)
 		c->frame = 0xa000;
 	else
 		return tcnh_cb(c);
-	ssp_set_buffer(0, c->nbuf);
+	ssp_set_buffer(0, n);
 	return ssp_submit_batch(&c->frame, 1, 2, 0, 0);
 }
 
@@ -143,6 +146,7 @@ static int gains_cb(struct ads8688_control *c)
 	c->frame = cc + 5 << 9;
 	if (f & 0x100)
 		c->frame |= 0x100 | c->gains >> 4*cc;
+	ssp_set_buffer(0, 1);
 	return 0;
 }
 
@@ -181,7 +185,6 @@ static int ads8688_start(int nskip, int nread)
 	c->status = 0x100;
 	c->job.command = &c->frame;
 	c->job.count = 1 + nskip + nread;
-	c->job.idle_frame = 0;
 	c->match.frame_count = nskip;
 	c->match.read_count = nread;
 	return ssp_start_batch(ads8688_batch, 0);
@@ -204,7 +207,6 @@ int adc_gains_cmd(struct command *cmd, const struct command_par *par)
 	}
 	unsigned int newgains = c->gains; // volatile
 
-	c->nbuf = 8;
 	c->job.cmd_count = 1;
 	c->callback = gains_cb;
 	int r = ads8688_start(1, 1);
@@ -237,6 +239,7 @@ int adc_read_cmd(struct command *cmd, const struct command_par *par)
 		c->callback = read_auto_cb;
 	}
 	c->job.cmd_count = 0; // idle_frame = continue command
+	c->nbuf = NSCRATCH;
 	int r = ads8688_start(aidx+1, 1);
 	int code = par->code;
 	if (r)
@@ -262,7 +265,7 @@ int adc_print_cmd(struct command *cmd, const struct command_par *par)
 		FLAG_VAL("abort",  0x04000000),
 		{}
 	};
-	unsigned int chs = 0;
+	unsigned int chs = (unsigned int)par->par;
 	error_msg_t e = parse_flags(cmd, kw, &chs);
 	if (e)
 		return parser_error_message(cmd, e);
@@ -467,5 +470,6 @@ const struct keywords adc_commands[] = {
 	CMD_KW("gains", adc_gains_cmd, 372, 0),
 	CMD_KW("read",  adc_read_cmd,  374, 0),
 	CMD_KW("print", adc_print_cmd, 376, 0),
+	CMD_KWF("status",adc_print_cmd, 376, 0x01000000),
 	CMD_END
 };

ltc2656.c

@@ -10,7 +10,7 @@ int ltc2656(unsigned int frame, int flags, int timeout)
 	else
 		ssp_deassert_ssel();
 	ssp_assert_ssel();
-	ssp_set_buffer(0,0);
+	ssp_set_buffer(0, -1);
 	unsigned short cmd[2] = { frame >> 16, frame & 0xffff };
 	ssp_submit(cmd, 2, 2, 0);
 	int r = ssp_wait(timeout);

ssp.c

@@ -29,8 +29,8 @@ void ssp_set_buffer(short *buf, unsigned int size)
 	volatile struct ssp_job *j=&job;
 	if (!buf) {
 		buf = ssp_scratch;
-		if (!size || size > sizeof(ssp_scratch)/2)
-			size = sizeof(ssp_scratch)/2;
+		if (size > NSCRATCH)
+			size = NSCRATCH;
 	}
 	ssp_buffer = (unsigned short *)buf;
 	j->buf_ptr = (unsigned short *)buf;
@@ -184,8 +184,8 @@ int ssp_submit_job(const struct ssp_job *jj)
 {
 	unsigned int iflg = disable_irq(INT_DISABLE);
 	memcpy((void*)&job, jj, sizeof(job)-8);
-	if (jj->buf_ptr || jj->buf_count)
-		ssp_set_buffer(0, jj->buf_count);
+	if (jj->buf_count)
+		ssp_set_buffer(jj->buf_ptr, jj->buf_count);
 	ssp_frames_sent = 0;
 	ssp_frames_read = 0;
 	ssp_callback = ssp_run_batch;
@@ -333,7 +333,7 @@ int ssp_run_batch()
 			ssp_init(batch->ssel);
 
 		if (f & ssp_b_scratch)
-			ssp_set_buffer(0, 0);
+			ssp_set_buffer(0, -1);
 
 		if (c == ssp_b_buffer)
 			ssp_set_buffer(batch->buffer, f & 0xffff);
@@ -618,7 +618,7 @@ int ssp_send_cmd(struct command *cmd, const struct command_par *par)
 		if (frames < reads)
 			frames = reads;
 	}
-	ssp_set_buffer(0,0);
+	ssp_set_buffer(0, -1);
 	int c = ssp_submit(ssp_scratch, n, frames, reads);
 	parser_format_message(cmd, "%03d ssp %d frames %dw %dr → %d\n",
 			      par->code, frames, n, reads, c);