---

yaml
---
r: 363103
b: refs/heads/master
c: aceca28
h: refs/heads/master
i:
  363101: 3e33a85
  363099: 76663eb
  363095: e61f328
  363087: 2aae9f9
  363071: 8d30774
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 96dd86fa588169b745a71aedf2070e80f4943623
+refs/heads/master: aceca2854498de7384ee7b44d8eb7820fd4c7f16

trunk/drivers/w1/slaves/Kconfig

@@ -22,6 +22,16 @@ config W1_SLAVE_DS2408
 	  Say Y here if you want to use a 1-wire
 	  DS2408 8-Channel Addressable Switch device support
 
+config W1_SLAVE_DS2408_READBACK
+	bool "Read-back values written to DS2408's output register"
+	depends on W1_SLAVE_DS2408
+	default y
+	help
+	  Enabling this will cause the driver to read back the values written
+	  to the chip's output register in order to detect errors.
+
+	  This is slower but useful when debugging chips and/or busses.
+
 config W1_SLAVE_DS2413
 	tristate "Dual Channel Addressable Switch 0x3a family support (DS2413)"
 	help

trunk/drivers/w1/slaves/w1_ds2408.c

@@ -178,6 +178,15 @@ static ssize_t w1_f29_write_output(
 		w1_write_block(sl->master, w1_buf, 3);
 
 		readBack = w1_read_8(sl->master);
+
+		if (readBack != W1_F29_SUCCESS_CONFIRM_BYTE) {
+			if (w1_reset_resume_command(sl->master))
+				goto error;
+			/* try again, the slave is ready for a command */
+			continue;
+		}
+
+#ifdef CONFIG_W1_SLAVE_DS2408_READBACK
 		/* here the master could read another byte which
 		   would be the PIO reg (the actual pin logic state)
 		   since in this driver we don't know which pins are
@@ -186,19 +195,16 @@ static ssize_t w1_f29_write_output(
 		if (w1_reset_resume_command(sl->master))
 			goto error;
 
-		if (readBack != 0xAA) {
-			/* try again, the slave is ready for a command */
-			continue;
-		}
-
 		/* go read back the output latches */
 		/* (the direct effect of the write above) */
 		w1_buf[0] = W1_F29_FUNC_READ_PIO_REGS;
 		w1_buf[1] = W1_F29_REG_OUTPUT_LATCH_STATE;
 		w1_buf[2] = 0;
 		w1_write_block(sl->master, w1_buf, 3);
 		/* read the result of the READ_PIO_REGS command */
-		if (w1_read_8(sl->master) == *buf) {
+		if (w1_read_8(sl->master) == *buf)
+#endif
+		{
 			/* success! */
 			mutex_unlock(&sl->master->bus_mutex);
 			dev_dbg(&sl->dev,