Merge remote-tracking branch 'regmap/topic/async' into regmap-next

2013-02-14 17:11:03 +00:00
parent 3bef9059dd 95601d65a1
commit 3689cf7fd1
4 changed files with 354 additions and 47 deletions
--- a/drivers/base/regmap/regmap.c
+++ b/drivers/base/regmap/regmap.c
@@ -16,6 +16,7 @@
 #include <linux/mutex.h>
 #include <linux/err.h>
 #include <linux/rbtree.h>
+#include <linux/sched.h>

 #define CREATE_TRACE_POINTS
 #include <trace/events/regmap.h>
@@ -34,6 +35,22 @@ static int _regmap_update_bits(struct regmap *map, unsigned int reg,
 			       unsigned int mask, unsigned int val,
 			       bool *change);

+static int _regmap_bus_read(void *context, unsigned int reg,
+			    unsigned int *val);
+static int _regmap_bus_formatted_write(void *context, unsigned int reg,
+				       unsigned int val);
+static int _regmap_bus_raw_write(void *context, unsigned int reg,
+				 unsigned int val);
+
+static void async_cleanup(struct work_struct *work)
+{
+	struct regmap_async *async = container_of(work, struct regmap_async,
+						  cleanup);
+
+	kfree(async->work_buf);
+	kfree(async);
+}
+
 bool regmap_reg_in_ranges(unsigned int reg,
 			  const struct regmap_range *ranges,
 			  unsigned int nranges)
@@ -423,6 +440,10 @@ struct regmap *regmap_init(struct device *dev,
 	map->cache_type = config->cache_type;
 	map->name = config->name;

+	spin_lock_init(&map->async_lock);
+	INIT_LIST_HEAD(&map->async_list);
+	init_waitqueue_head(&map->async_waitq);
+
 	if (config->read_flag_mask || config->write_flag_mask) {
 		map->read_flag_mask = config->read_flag_mask;
 		map->write_flag_mask = config->write_flag_mask;
@@ -430,6 +451,8 @@ struct regmap *regmap_init(struct device *dev,
 		map->read_flag_mask = bus->read_flag_mask;
 	}

+	map->reg_read = _regmap_bus_read;
+
 	reg_endian = config->reg_format_endian;
 	if (reg_endian == REGMAP_ENDIAN_DEFAULT)
 		reg_endian = bus->reg_format_endian_default;
@@ -581,6 +604,11 @@ struct regmap *regmap_init(struct device *dev,
 		goto err_map;
 	}

+	if (map->format.format_write)
+		map->reg_write = _regmap_bus_formatted_write;
+	else if (map->format.format_val)
+		map->reg_write = _regmap_bus_raw_write;
+
 	map->range_tree = RB_ROOT;
 	for (i = 0; i < config->num_ranges; i++) {
 		const struct regmap_range_cfg *range_cfg = &config->ranges[i];
@@ -876,10 +904,13 @@ static int _regmap_select_page(struct regmap *map, unsigned int *reg,
 }

 static int _regmap_raw_write(struct regmap *map, unsigned int reg,
-			     const void *val, size_t val_len)
+			     const void *val, size_t val_len, bool async)
 {
 	struct regmap_range_node *range;
+	unsigned long flags;
 	u8 *u8 = map->work_buf;
+	void *work_val = map->work_buf + map->format.reg_bytes +
+		map->format.pad_bytes;
 	void *buf;
 	int ret = -ENOTSUPP;
 	size_t len;
@@ -924,7 +955,7 @@ static int _regmap_raw_write(struct regmap *map, unsigned int reg,
 			dev_dbg(map->dev, "Writing window %d/%zu\n",
 				win_residue, val_len / map->format.val_bytes);
 			ret = _regmap_raw_write(map, reg, val, win_residue *
-						map->format.val_bytes);
+						map->format.val_bytes, async);
 			if (ret != 0)
 				return ret;

@@ -947,6 +978,50 @@ static int _regmap_raw_write(struct regmap *map, unsigned int reg,

 	u8[0] |= map->write_flag_mask;

+	if (async && map->bus->async_write) {
+		struct regmap_async *async = map->bus->async_alloc();
+		if (!async)
+			return -ENOMEM;
+
+		async->work_buf = kzalloc(map->format.buf_size,
+					  GFP_KERNEL | GFP_DMA);
+		if (!async->work_buf) {
+			kfree(async);
+			return -ENOMEM;
+		}
+
+		INIT_WORK(&async->cleanup, async_cleanup);
+		async->map = map;
+
+		/* If the caller supplied the value we can use it safely. */
+		memcpy(async->work_buf, map->work_buf, map->format.pad_bytes +
+		       map->format.reg_bytes + map->format.val_bytes);
+		if (val == work_val)
+			val = async->work_buf + map->format.pad_bytes +
+				map->format.reg_bytes;
+
+		spin_lock_irqsave(&map->async_lock, flags);
+		list_add_tail(&async->list, &map->async_list);
+		spin_unlock_irqrestore(&map->async_lock, flags);
+
+		ret = map->bus->async_write(map->bus_context, async->work_buf,
+					    map->format.reg_bytes +
+					    map->format.pad_bytes,
+					    val, val_len, async);
+
+		if (ret != 0) {
+			dev_err(map->dev, "Failed to schedule write: %d\n",
+				ret);
+
+			spin_lock_irqsave(&map->async_lock, flags);
+			list_del(&async->list);
+			spin_unlock_irqrestore(&map->async_lock, flags);
+
+			kfree(async->work_buf);
+			kfree(async);
+		}
+	}
+
 	trace_regmap_hw_write_start(map->dev, reg,
 				    val_len / map->format.val_bytes);

@@ -954,8 +1029,7 @@ static int _regmap_raw_write(struct regmap *map, unsigned int reg,
 	 * send the work_buf directly, otherwise try to do a gather
 	 * write.
 	 */
-	if (val == (map->work_buf + map->format.pad_bytes +
-		    map->format.reg_bytes))
+	if (val == work_val)
 		ret = map->bus->write(map->bus_context, map->work_buf,
 				      map->format.reg_bytes +
 				      map->format.pad_bytes +
@@ -987,12 +1061,54 @@ static int _regmap_raw_write(struct regmap *map, unsigned int reg,
 	return ret;
 }

+static int _regmap_bus_formatted_write(void *context, unsigned int reg,
+				       unsigned int val)
+{
+	int ret;
+	struct regmap_range_node *range;
+	struct regmap *map = context;
+
+	BUG_ON(!map->format.format_write);
+
+	range = _regmap_range_lookup(map, reg);
+	if (range) {
+		ret = _regmap_select_page(map, &reg, range, 1);
+		if (ret != 0)
+			return ret;
+	}
+
+	map->format.format_write(map, reg, val);
+
+	trace_regmap_hw_write_start(map->dev, reg, 1);
+
+	ret = map->bus->write(map->bus_context, map->work_buf,
+			      map->format.buf_size);
+
+	trace_regmap_hw_write_done(map->dev, reg, 1);
+
+	return ret;
+}
+
+static int _regmap_bus_raw_write(void *context, unsigned int reg,
+				 unsigned int val)
+{
+	struct regmap *map = context;
+
+	BUG_ON(!map->format.format_val);
+
+	map->format.format_val(map->work_buf + map->format.reg_bytes
+			       + map->format.pad_bytes, val, 0);
+	return _regmap_raw_write(map, reg,
+				 map->work_buf +
+				 map->format.reg_bytes +
+				 map->format.pad_bytes,
+				 map->format.val_bytes, false);
+}
+
 int _regmap_write(struct regmap *map, unsigned int reg,
 		  unsigned int val)
 {
-	struct regmap_range_node *range;
 	int ret;
-	BUG_ON(!map->format.format_write && !map->format.format_val);

 	if (!map->cache_bypass && map->format.format_write) {
 		ret = regcache_write(map, reg, val);
@@ -1011,33 +1127,7 @@ int _regmap_write(struct regmap *map, unsigned int reg,

 	trace_regmap_reg_write(map->dev, reg, val);

-	if (map->format.format_write) {
-		range = _regmap_range_lookup(map, reg);
-		if (range) {
-			ret = _regmap_select_page(map, &reg, range, 1);
-			if (ret != 0)
-				return ret;
-		}
-
-		map->format.format_write(map, reg, val);
-
-		trace_regmap_hw_write_start(map->dev, reg, 1);
-
-		ret = map->bus->write(map->bus_context, map->work_buf,
-				      map->format.buf_size);
-
-		trace_regmap_hw_write_done(map->dev, reg, 1);
-
-		return ret;
-	} else {
-		map->format.format_val(map->work_buf + map->format.reg_bytes
-				       + map->format.pad_bytes, val, 0);
-		return _regmap_raw_write(map, reg,
-					 map->work_buf +
-					 map->format.reg_bytes +
-					 map->format.pad_bytes,
-					 map->format.val_bytes);
-	}
+	return map->reg_write(map, reg, val);
 }

 /**
@@ -1095,7 +1185,7 @@ int regmap_raw_write(struct regmap *map, unsigned int reg,

 	map->lock(map->lock_arg);

-	ret = _regmap_raw_write(map, reg, val, val_len);
+	ret = _regmap_raw_write(map, reg, val, val_len, false);

 	map->unlock(map->lock_arg);

@@ -1151,14 +1241,15 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val,
 	if (map->use_single_rw) {
 		for (i = 0; i < val_count; i++) {
 			ret = regmap_raw_write(map,
-						reg + (i * map->reg_stride),
-						val + (i * val_bytes),
-						val_bytes);
+					       reg + (i * map->reg_stride),
+					       val + (i * val_bytes),
+					       val_bytes);
 			if (ret != 0)
 				return ret;
 		}
 	} else {
-		ret = _regmap_raw_write(map, reg, wval, val_bytes * val_count);
+		ret = _regmap_raw_write(map, reg, wval, val_bytes * val_count,
+					false);
 	}

 	if (val_bytes != 1)
@@ -1170,6 +1261,48 @@ out:
 }
 EXPORT_SYMBOL_GPL(regmap_bulk_write);

+/**
+ * regmap_raw_write_async(): Write raw values to one or more registers
+ *                           asynchronously
+ *
+ * @map: Register map to write to
+ * @reg: Initial register to write to
+ * @val: Block of data to be written, laid out for direct transmission to the
+ *       device.  Must be valid until regmap_async_complete() is called.
+ * @val_len: Length of data pointed to by val.
+ *
+ * This function is intended to be used for things like firmware
+ * download where a large block of data needs to be transferred to the
+ * device.  No formatting will be done on the data provided.
+ *
+ * If supported by the underlying bus the write will be scheduled
+ * asynchronously, helping maximise I/O speed on higher speed buses
+ * like SPI.  regmap_async_complete() can be called to ensure that all
+ * asynchrnous writes have been completed.
+ *
+ * A value of zero will be returned on success, a negative errno will
+ * be returned in error cases.
+ */
+int regmap_raw_write_async(struct regmap *map, unsigned int reg,
+			   const void *val, size_t val_len)
+{
+	int ret;
+
+	if (val_len % map->format.val_bytes)
+		return -EINVAL;
+	if (reg % map->reg_stride)
+		return -EINVAL;
+
+	map->lock(map->lock_arg);
+
+	ret = _regmap_raw_write(map, reg, val, val_len, true);
+
+	map->unlock(map->lock_arg);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_raw_write_async);
+
 static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
 			    unsigned int val_len)
 {
@@ -1208,10 +1341,27 @@ static int _regmap_raw_read(struct regmap *map, unsigned int reg, void *val,
 	return ret;
 }

+static int _regmap_bus_read(void *context, unsigned int reg,
+			    unsigned int *val)
+{
+	int ret;
+	struct regmap *map = context;
+
+	if (!map->format.parse_val)
+		return -EINVAL;
+
+	ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
+	if (ret == 0)
+		*val = map->format.parse_val(map->work_buf);
+
+	return ret;
+}
+
 static int _regmap_read(struct regmap *map, unsigned int reg,
 			unsigned int *val)
 {
 	int ret;
+	BUG_ON(!map->reg_read);

 	if (!map->cache_bypass) {
 		ret = regcache_read(map, reg, val);
@@ -1219,26 +1369,21 @@ static int _regmap_read(struct regmap *map, unsigned int reg,
 			return 0;
 	}

-	if (!map->format.parse_val)
-		return -EINVAL;
-
 	if (map->cache_only)
 		return -EBUSY;

-	ret = _regmap_raw_read(map, reg, map->work_buf, map->format.val_bytes);
+	ret = map->reg_read(map, reg, val);
 	if (ret == 0) {
-		*val = map->format.parse_val(map->work_buf);
-
 #ifdef LOG_DEVICE
 		if (strcmp(dev_name(map->dev), LOG_DEVICE) == 0)
 			dev_info(map->dev, "%x => %x\n", reg, *val);
 #endif

 		trace_regmap_reg_read(map->dev, reg, *val);
-	}

-	if (ret == 0 && !map->cache_bypass)
-		regcache_write(map, reg, *val);
+		if (!map->cache_bypass)
+			regcache_write(map, reg, *val);
+	}

 	return ret;
 }
@@ -1456,6 +1601,68 @@ int regmap_update_bits_check(struct regmap *map, unsigned int reg,
 }
 EXPORT_SYMBOL_GPL(regmap_update_bits_check);

+void regmap_async_complete_cb(struct regmap_async *async, int ret)
+{
+	struct regmap *map = async->map;
+	bool wake;
+
+	spin_lock(&map->async_lock);
+
+	list_del(&async->list);
+	wake = list_empty(&map->async_list);
+
+	if (ret != 0)
+		map->async_ret = ret;
+
+	spin_unlock(&map->async_lock);
+
+	schedule_work(&async->cleanup);
+
+	if (wake)
+		wake_up(&map->async_waitq);
+}
+EXPORT_SYMBOL_GPL(regmap_async_complete_cb);
+
+static int regmap_async_is_done(struct regmap *map)
+{
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&map->async_lock, flags);
+	ret = list_empty(&map->async_list);
+	spin_unlock_irqrestore(&map->async_lock, flags);
+
+	return ret;
+}
+
+/**
+ * regmap_async_complete: Ensure all asynchronous I/O has completed.
+ *
+ * @map: Map to operate on.
+ *
+ * Blocks until any pending asynchronous I/O has completed.  Returns
+ * an error code for any failed I/O operations.
+ */
+int regmap_async_complete(struct regmap *map)
+{
+	unsigned long flags;
+	int ret;
+
+	/* Nothing to do with no async support */
+	if (!map->bus->async_write)
+		return 0;
+
+	wait_event(map->async_waitq, regmap_async_is_done(map));
+
+	spin_lock_irqsave(&map->async_lock, flags);
+	ret = map->async_ret;
+	map->async_ret = 0;
+	spin_unlock_irqrestore(&map->async_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(regmap_async_complete);
+
 /**
 * regmap_register_patch: Register and apply register updates to be applied
 *                        on device initialistion