Merge remote-tracking branch 'spi/topic/doc' into spi-next

include/linux/spi/spi.h

@@ -51,6 +51,8 @@ extern struct bus_type spi_bus_type;
  * @bytes_tx:      number of bytes sent to device
  * @bytes_rx:      number of bytes received from device
  *
+ * @transfer_bytes_histo:
+ *                 transfer bytes histogramm
  */
 struct spi_statistics {
 	spinlock_t		lock; /* lock for the whole structure */
@@ -68,6 +70,8 @@ struct spi_statistics {
 	unsigned long long	bytes_rx;
 	unsigned long long	bytes_tx;
 
+#define SPI_STATISTICS_HISTO_SIZE 17
+	unsigned long transfer_bytes_histo[SPI_STATISTICS_HISTO_SIZE];
 };
 
 void spi_statistics_add_transfer_stats(struct spi_statistics *stats,
@@ -843,8 +847,10 @@ extern int spi_bus_unlock(struct spi_master *master);
  * @len: data buffer size
  * Context: can sleep
  *
- * This writes the buffer and returns zero or a negative error code.
+ * This function writes the buffer @buf.
  * Callable only from contexts that can sleep.
+ *
+ * Return: zero on success, else a negative error code.
  */
 static inline int
 spi_write(struct spi_device *spi, const void *buf, size_t len)
@@ -867,8 +873,10 @@ spi_write(struct spi_device *spi, const void *buf, size_t len)
  * @len: data buffer size
  * Context: can sleep
  *
- * This reads the buffer and returns zero or a negative error code.
+ * This function reads the buffer @buf.
  * Callable only from contexts that can sleep.
+ *
+ * Return: zero on success, else a negative error code.
  */
 static inline int
 spi_read(struct spi_device *spi, void *buf, size_t len)
@@ -895,7 +903,7 @@ spi_read(struct spi_device *spi, void *buf, size_t len)
  *
  * For more specific semantics see spi_sync().
  *
- * It returns zero on success, else a negative error code.
+ * Return: Return: zero on success, else a negative error code.
  */
 static inline int
 spi_sync_transfer(struct spi_device *spi, struct spi_transfer *xfers,
@@ -919,9 +927,10 @@ extern int spi_write_then_read(struct spi_device *spi,
  * @cmd: command to be written before data is read back
  * Context: can sleep
  *
- * This returns the (unsigned) eight bit number returned by the
- * device, or else a negative error code.  Callable only from
- * contexts that can sleep.
+ * Callable only from contexts that can sleep.
+ *
+ * Return: the (unsigned) eight bit number returned by the
+ * device, or else a negative error code.
  */
 static inline ssize_t spi_w8r8(struct spi_device *spi, u8 cmd)
 {
@@ -940,12 +949,13 @@ static inline ssize_t spi_w8r8(struct spi_device *spi, u8 cmd)
  * @cmd: command to be written before data is read back
  * Context: can sleep
  *
- * This returns the (unsigned) sixteen bit number returned by the
- * device, or else a negative error code.  Callable only from
- * contexts that can sleep.
- *
  * The number is returned in wire-order, which is at least sometimes
  * big-endian.
+ *
+ * Callable only from contexts that can sleep.
+ *
+ * Return: the (unsigned) sixteen bit number returned by the
+ * device, or else a negative error code.
  */
 static inline ssize_t spi_w8r16(struct spi_device *spi, u8 cmd)
 {
@@ -964,13 +974,13 @@ static inline ssize_t spi_w8r16(struct spi_device *spi, u8 cmd)
  * @cmd: command to be written before data is read back
  * Context: can sleep
  *
- * This returns the (unsigned) sixteen bit number returned by the device in cpu
- * endianness, or else a negative error code. Callable only from contexts that
- * can sleep.
- *
  * This function is similar to spi_w8r16, with the exception that it will
  * convert the read 16 bit data word from big-endian to native endianness.
  *
+ * Callable only from contexts that can sleep.
+ *
+ * Return: the (unsigned) sixteen bit number returned by the device in cpu
+ * endianness, or else a negative error code.
  */
 static inline ssize_t spi_w8r16be(struct spi_device *spi, u8 cmd)