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Diffstat (limited to 'include/linux/spi/spi.h')
-rw-r--r--include/linux/spi/spi.h35
1 files changed, 31 insertions, 4 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 935bd2854ff1..0a78745e5766 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -29,8 +29,8 @@ struct spi_transfer;
struct spi_flash_read_message;
/*
- * INTERFACES between SPI master-side drivers and SPI infrastructure.
- * (There's no SPI slave support for Linux yet...)
+ * INTERFACES between SPI master-side drivers and SPI slave protocol handlers,
+ * and SPI infrastructure.
*/
extern struct bus_type spi_bus_type;
@@ -311,6 +311,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
* @min_speed_hz: Lowest supported transfer speed
* @max_speed_hz: Highest supported transfer speed
* @flags: other constraints relevant to this driver
+ * @slave: indicates that this is an SPI slave controller
* @max_transfer_size: function that returns the max transfer size for
* a &spi_device; may be %NULL, so the default %SIZE_MAX will be used.
* @max_message_size: function that returns the max message size for
@@ -374,6 +375,7 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
* @handle_err: the subsystem calls the driver to handle an error that occurs
* in the generic implementation of transfer_one_message().
* @unprepare_message: undo any work done by prepare_message().
+ * @slave_abort: abort the ongoing transfer request on an SPI slave controller
* @spi_flash_read: to support spi-controller hardwares that provide
* accelerated interface to read from flash devices.
* @spi_flash_can_dma: analogous to can_dma() interface, but for
@@ -447,6 +449,9 @@ struct spi_master {
#define SPI_MASTER_MUST_TX BIT(4) /* requires tx */
#define SPI_MASTER_GPIO_SS BIT(5) /* GPIO CS must select slave */
+ /* flag indicating this is an SPI slave controller */
+ bool slave;
+
/*
* on some hardware transfer / message size may be constrained
* the limit may depend on device transfer settings
@@ -539,6 +544,7 @@ struct spi_master {
struct spi_message *message);
int (*unprepare_message)(struct spi_master *master,
struct spi_message *message);
+ int (*slave_abort)(struct spi_master *spi);
int (*spi_flash_read)(struct spi_device *spi,
struct spi_flash_read_message *msg);
bool (*spi_flash_can_dma)(struct spi_device *spi,
@@ -595,6 +601,11 @@ static inline void spi_master_put(struct spi_master *master)
put_device(&master->dev);
}
+static inline bool spi_controller_is_slave(struct spi_master *ctlr)
+{
+ return IS_ENABLED(CONFIG_SPI_SLAVE) && ctlr->slave;
+}
+
/* PM calls that need to be issued by the driver */
extern int spi_master_suspend(struct spi_master *master);
extern int spi_master_resume(struct spi_master *master);
@@ -605,8 +616,23 @@ extern void spi_finalize_current_message(struct spi_master *master);
extern void spi_finalize_current_transfer(struct spi_master *master);
/* the spi driver core manages memory for the spi_master classdev */
-extern struct spi_master *
-spi_alloc_master(struct device *host, unsigned size);
+extern struct spi_master *__spi_alloc_controller(struct device *host,
+ unsigned int size, bool slave);
+
+static inline struct spi_master *spi_alloc_master(struct device *host,
+ unsigned int size)
+{
+ return __spi_alloc_controller(host, size, false);
+}
+
+static inline struct spi_master *spi_alloc_slave(struct device *host,
+ unsigned int size)
+{
+ if (!IS_ENABLED(CONFIG_SPI_SLAVE))
+ return NULL;
+
+ return __spi_alloc_controller(host, size, true);
+}
extern int spi_register_master(struct spi_master *master);
extern int devm_spi_register_master(struct device *dev,
@@ -912,6 +938,7 @@ extern int spi_setup(struct spi_device *spi);
extern int spi_async(struct spi_device *spi, struct spi_message *message);
extern int spi_async_locked(struct spi_device *spi,
struct spi_message *message);
+extern int spi_slave_abort(struct spi_device *spi);
static inline size_t
spi_max_message_size(struct spi_device *spi)