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path: root/drivers/spi/spi.c
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Diffstat (limited to 'drivers/spi/spi.c')
-rw-r--r--drivers/spi/spi.c33
1 files changed, 28 insertions, 5 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 6657331eed93..c3219b29b5ac 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -152,6 +152,11 @@ static void spi_drv_shutdown(struct device *dev)
sdrv->shutdown(to_spi_device(dev));
}
+/**
+ * spi_register_driver - register a SPI driver
+ * @sdrv: the driver to register
+ * Context: can sleep
+ */
int spi_register_driver(struct spi_driver *sdrv)
{
sdrv->driver.bus = &spi_bus_type;
@@ -183,7 +188,13 @@ static LIST_HEAD(board_list);
static DECLARE_MUTEX(board_lock);
-/* On typical mainboards, this is purely internal; and it's not needed
+/**
+ * spi_new_device - instantiate one new SPI device
+ * @master: Controller to which device is connected
+ * @chip: Describes the SPI device
+ * Context: can sleep
+ *
+ * On typical mainboards, this is purely internal; and it's not needed
* after board init creates the hard-wired devices. Some development
* platforms may not be able to use spi_register_board_info though, and
* this is exported so that for example a USB or parport based adapter
@@ -251,7 +262,12 @@ fail:
}
EXPORT_SYMBOL_GPL(spi_new_device);
-/*
+/**
+ * spi_register_board_info - register SPI devices for a given board
+ * @info: array of chip descriptors
+ * @n: how many descriptors are provided
+ * Context: can sleep
+ *
* Board-specific early init code calls this (probably during arch_initcall)
* with segments of the SPI device table. Any device nodes are created later,
* after the relevant parent SPI controller (bus_num) is defined. We keep
@@ -337,9 +353,10 @@ static struct class spi_master_class = {
/**
* spi_alloc_master - allocate SPI master controller
* @dev: the controller, possibly using the platform_bus
- * @size: how much driver-private data to preallocate; the pointer to this
+ * @size: how much zeroed driver-private data to allocate; the pointer to this
* memory is in the class_data field of the returned class_device,
* accessible with spi_master_get_devdata().
+ * Context: can sleep
*
* This call is used only by SPI master controller drivers, which are the
* only ones directly touching chip registers. It's how they allocate
@@ -375,6 +392,7 @@ EXPORT_SYMBOL_GPL(spi_alloc_master);
/**
* spi_register_master - register SPI master controller
* @master: initialized master, originally from spi_alloc_master()
+ * Context: can sleep
*
* SPI master controllers connect to their drivers using some non-SPI bus,
* such as the platform bus. The final stage of probe() in that code
@@ -437,6 +455,7 @@ static int __unregister(struct device *dev, void *unused)
/**
* spi_unregister_master - unregister SPI master controller
* @master: the master being unregistered
+ * Context: can sleep
*
* This call is used only by SPI master controller drivers, which are the
* only ones directly touching chip registers.
@@ -455,6 +474,7 @@ EXPORT_SYMBOL_GPL(spi_unregister_master);
/**
* spi_busnum_to_master - look up master associated with bus_num
* @bus_num: the master's bus number
+ * Context: can sleep
*
* This call may be used with devices that are registered after
* arch init time. It returns a refcounted pointer to the relevant
@@ -492,6 +512,7 @@ static void spi_complete(void *arg)
* spi_sync - blocking/synchronous SPI data transfers
* @spi: device with which data will be exchanged
* @message: describes the data transfers
+ * Context: can sleep
*
* This call may only be used from a context that may sleep. The sleep
* is non-interruptible, and has no timeout. Low-overhead controller
@@ -508,7 +529,7 @@ static void spi_complete(void *arg)
*
* The return value is a negative error code if the message could not be
* submitted, else zero. When the value is zero, then message->status is
- * also defined: it's the completion code for the transfer, either zero
+ * also defined; it's the completion code for the transfer, either zero
* or a negative error code from the controller driver.
*/
int spi_sync(struct spi_device *spi, struct spi_message *message)
@@ -538,6 +559,7 @@ static u8 *buf;
* @n_tx: size of txbuf, in bytes
* @rxbuf: buffer into which data will be read
* @n_rx: size of rxbuf, in bytes (need not be dma-safe)
+ * Context: can sleep
*
* This performs a half duplex MicroWire style transaction with the
* device, sending txbuf and then reading rxbuf. The return value
@@ -545,7 +567,8 @@ static u8 *buf;
* This call may only be used from a context that may sleep.
*
* Parameters to this routine are always copied using a small buffer;
- * performance-sensitive or bulk transfer code should instead use
+ * portable code should never use this for more than 32 bytes.
+ * Performance-sensitive or bulk transfer code should instead use
* spi_{async,sync}() calls with dma-safe buffers.
*/
int spi_write_then_read(struct spi_device *spi,