Merge tag 'char-misc-5.2-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc update part 2 from Greg KH:
 "Here is the "real" big set of char/misc driver patches for 5.2-rc1

  Loads of different driver subsystem stuff in here, all over the places:
   - thunderbolt driver updates
   - habanalabs driver updates
   - nvmem driver updates
   - extcon driver updates
   - intel_th driver updates
   - mei driver updates
   - coresight driver updates
   - soundwire driver cleanups and updates
   - fastrpc driver updates
   - other minor driver updates
   - chardev minor fixups

  Feels like this tree is getting to be a dumping ground of "small
  driver subsystems" these days. Which is fine with me, if it makes
  things easier for those subsystem maintainers.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'char-misc-5.2-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (255 commits)
  intel_th: msu: Add current window tracking
  intel_th: msu: Add a sysfs attribute to trigger window switch
  intel_th: msu: Correct the block wrap detection
  intel_th: Add switch triggering support
  intel_th: gth: Factor out trace start/stop
  intel_th: msu: Factor out pipeline draining
  intel_th: msu: Switch over to scatterlist
  intel_th: msu: Replace open-coded list_{first,last,next}_entry variants
  intel_th: Only report useful IRQs to subdevices
  intel_th: msu: Start handling IRQs
  intel_th: pci: Use MSI interrupt signalling
  intel_th: Communicate IRQ via resource
  intel_th: Add "rtit" source device
  intel_th: Skip subdevices if their MMIO is missing
  intel_th: Rework resource passing between glue layers and core
  intel_th: SPDX-ify the documentation
  intel_th: msu: Fix single mode with IOMMU
  coresight: funnel: Support static funnel
  dt-bindings: arm: coresight: Unify funnel DT binding
  coresight: replicator: Add new device id for static replicator
  ...

3 files changed, 51 insertions, 46 deletions

diff --git a/drivers/w1/masters/ds2482.c b/drivers/w1/masters/ds2482.c
index 8b5e598ffdb3..8f2b25f1614c 100644
--- a/drivers/w1/masters/ds2482.c
+++ b/drivers/w1/masters/ds2482.c
@@ -37,6 +37,11 @@ module_param_named(active_pullup, ds2482_active_pullup, int, 0644);
 MODULE_PARM_DESC(active_pullup, "Active pullup (apply to all buses): " \
 				"0-disable, 1-enable (default)");
 
+/* extra configurations - e.g. 1WS */
+static int extra_config;
+module_param(extra_config, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(extra_config, "Extra Configuration settings 1=APU,2=PPM,3=SPU,8=1WS");
+
 /**
  * The DS2482 registers - there are 3 registers that are addressed by a read
  * pointer. The read pointer is set by the last command executed.
@@ -70,8 +75,6 @@ MODULE_PARM_DESC(active_pullup, "Active pullup (apply to all buses): " \
 #define DS2482_REG_CFG_PPM		0x02	/* presence pulse masking */
 #define DS2482_REG_CFG_APU		0x01	/* active pull-up */
 
-/* extra configurations - e.g. 1WS */
-static int extra_config;
 
 /**
  * Write and verify codes for the CHANNEL_SELECT command (DS2482-800 only).
@@ -130,6 +133,8 @@ struct ds2482_data {
  */
 static inline u8 ds2482_calculate_config(u8 conf)
 {
+	conf |= extra_config;
+
 	if (ds2482_active_pullup)
 		conf |= DS2482_REG_CFG_APU;
 
@@ -405,7 +410,7 @@ static u8 ds2482_w1_reset_bus(void *data)
 		/* If the chip did reset since detect, re-config it */
 		if (err & DS2482_REG_STS_RST)
 			ds2482_send_cmd_data(pdev, DS2482_CMD_WRITE_CONFIG,
-					ds2482_calculate_config(extra_config));
+					     ds2482_calculate_config(0x00));
 	}
 
 	mutex_unlock(&pdev->access_lock);
@@ -431,7 +436,8 @@ static u8 ds2482_w1_set_pullup(void *data, int delay)
 		ds2482_wait_1wire_idle(pdev);
 		/* note: it seems like both SPU and APU have to be set! */
 		retval = ds2482_send_cmd_data(pdev, DS2482_CMD_WRITE_CONFIG,
-			ds2482_calculate_config(extra_config|DS2482_REG_CFG_SPU|DS2482_REG_CFG_APU));
+			ds2482_calculate_config(DS2482_REG_CFG_SPU |
+						DS2482_REG_CFG_APU));
 		ds2482_wait_1wire_idle(pdev);
 	}
 
@@ -484,7 +490,7 @@ static int ds2482_probe(struct i2c_client *client,
 
 	/* Set all config items to 0 (off) */
 	ds2482_send_cmd_data(data, DS2482_CMD_WRITE_CONFIG,
-		ds2482_calculate_config(extra_config));
+		ds2482_calculate_config(0x00));
 
 	mutex_init(&data->access_lock);
 
@@ -559,7 +565,5 @@ module_i2c_driver(ds2482_driver);
 
 MODULE_AUTHOR("Ben Gardner <bgardner@wabtec.com>");
 MODULE_DESCRIPTION("DS2482 driver");
-module_param(extra_config, int, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(extra_config, "Extra Configuration settings 1=APU,2=PPM,3=SPU,8=1WS");
 
 MODULE_LICENSE("GPL");
diff --git a/drivers/w1/slaves/w1_ds2408.c b/drivers/w1/slaves/w1_ds2408.c
index b535d5ec35b6..92e8f0755b9a 100644
--- a/drivers/w1/slaves/w1_ds2408.c
+++ b/drivers/w1/slaves/w1_ds2408.c
@@ -138,14 +138,37 @@ static ssize_t status_control_read(struct file *filp, struct kobject *kobj,
 		W1_F29_REG_CONTROL_AND_STATUS, buf);
 }
 
+#ifdef fCONFIG_W1_SLAVE_DS2408_READBACK
+static bool optional_read_back_valid(struct w1_slave *sl, u8 expected)
+{
+	u8 w1_buf[3];
+
+	if (w1_reset_resume_command(sl->master))
+		return false;
+
+	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);
+
+	return (w1_read_8(sl->master) == expected);
+}
+#else
+static bool optional_read_back_valid(struct w1_slave *sl, u8 expected)
+{
+	return true;
+}
+#endif
+
 static ssize_t output_write(struct file *filp, struct kobject *kobj,
 			    struct bin_attribute *bin_attr, char *buf,
 			    loff_t off, size_t count)
 {
 	struct w1_slave *sl = kobj_to_w1_slave(kobj);
 	u8 w1_buf[3];
-	u8 readBack;
 	unsigned int retries = W1_F29_RETRIES;
+	ssize_t bytes_written = -EIO;
 
 	if (count != 1 || off != 0)
 		return -EFAULT;
@@ -155,54 +178,33 @@ static ssize_t output_write(struct file *filp, struct kobject *kobj,
 	dev_dbg(&sl->dev, "mutex locked");
 
 	if (w1_reset_select_slave(sl))
-		goto error;
+		goto out;
 
-	while (retries--) {
+	do {
 		w1_buf[0] = W1_F29_FUNC_CHANN_ACCESS_WRITE;
 		w1_buf[1] = *buf;
 		w1_buf[2] = ~(*buf);
-		w1_write_block(sl->master, w1_buf, 3);
 
-		readBack = w1_read_8(sl->master);
+		w1_write_block(sl->master, w1_buf, 3);
 
-		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;
+		if (w1_read_8(sl->master) == W1_F29_SUCCESS_CONFIRM_BYTE &&
+		    optional_read_back_valid(sl, *buf)) {
+			bytes_written = 1;
+			goto out;
 		}
 
-#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
-		   in and outs, there's no value to read the state and
-		   compare. with (*buf) so end this command abruptly: */
 		if (w1_reset_resume_command(sl->master))
-			goto error;
+			goto out; /* unrecoverable error */
+		/* try again, the slave is ready for a command */
+	} while (--retries);
 
-		/* 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)
-#endif
-		{
-			/* success! */
-			mutex_unlock(&sl->master->bus_mutex);
-			dev_dbg(&sl->dev,
-				"mutex unlocked, retries:%d", retries);
-			return 1;
-		}
-	}
-error:
+out:
 	mutex_unlock(&sl->master->bus_mutex);
-	dev_dbg(&sl->dev, "mutex unlocked in error, retries:%d", retries);
 
-	return -EIO;
+	dev_dbg(&sl->dev, "%s, mutex unlocked retries:%d\n",
+		(bytes_written > 0) ? "succeeded" : "error", retries);
+
+	return bytes_written;
 }
 
 
diff --git a/drivers/w1/w1_io.c b/drivers/w1/w1_io.c
index 0364d3329c52..3516ce6718d9 100644
--- a/drivers/w1/w1_io.c
+++ b/drivers/w1/w1_io.c
@@ -432,8 +432,7 @@ int w1_reset_resume_command(struct w1_master *dev)
 	if (w1_reset_bus(dev))
 		return -1;
 
-	/* This will make only the last matched slave perform a skip ROM. */
-	w1_write_8(dev, W1_RESUME_CMD);
+	w1_write_8(dev, dev->slave_count > 1 ? W1_RESUME_CMD : W1_SKIP_ROM);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(w1_reset_resume_command);