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-rw-r--r--include/linux/spi/spi.h61
1 files changed, 59 insertions, 2 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 887116dbce2c..8c62ba74dd91 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -23,6 +23,7 @@
#include <linux/mod_devicetable.h>
#include <linux/slab.h>
#include <linux/kthread.h>
+#include <linux/completion.h>
/*
* INTERFACES between SPI master-side drivers and SPI infrastructure.
@@ -150,8 +151,7 @@ static inline void *spi_get_drvdata(struct spi_device *spi)
}
struct spi_message;
-
-
+struct spi_transfer;
/**
* struct spi_driver - Host side "protocol" driver
@@ -257,6 +257,9 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
* @queue_lock: spinlock to syncronise access to message queue
* @queue: message queue
* @cur_msg: the currently in-flight message
+ * @cur_msg_prepared: spi_prepare_message was called for the currently
+ * in-flight message
+ * @xfer_completion: used by core tranfer_one_message()
* @busy: message pump is busy
* @running: message pump is running
* @rt: whether this queue is set to run as a realtime task
@@ -274,6 +277,16 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
* @unprepare_transfer_hardware: there are currently no more messages on the
* queue so the subsystem notifies the driver that it may relax the
* hardware by issuing this call
+ * @set_cs: assert or deassert chip select, true to assert. May be called
+ * from interrupt context.
+ * @prepare_message: set up the controller to transfer a single message,
+ * for example doing DMA mapping. Called from threaded
+ * context.
+ * @transfer_one: transfer a single spi_transfer. When the
+ * driver is finished with this transfer it must call
+ * spi_finalize_current_transfer() so the subsystem can issue
+ * the next transfer
+ * @unprepare_message: undo any work done by prepare_message().
* @cs_gpios: Array of GPIOs to use as chip select lines; one per CS
* number. Any individual value may be -ENOENT for CS lines that
* are not GPIOs (driven by the SPI controller itself).
@@ -388,11 +401,25 @@ struct spi_master {
bool running;
bool rt;
bool auto_runtime_pm;
+ bool cur_msg_prepared;
+ struct completion xfer_completion;
int (*prepare_transfer_hardware)(struct spi_master *master);
int (*transfer_one_message)(struct spi_master *master,
struct spi_message *mesg);
int (*unprepare_transfer_hardware)(struct spi_master *master);
+ int (*prepare_message)(struct spi_master *master,
+ struct spi_message *message);
+ int (*unprepare_message)(struct spi_master *master,
+ struct spi_message *message);
+
+ /*
+ * These hooks are for drivers that use a generic implementation
+ * of transfer_one_message() provied by the core.
+ */
+ void (*set_cs)(struct spi_device *spi, bool enable);
+ int (*transfer_one)(struct spi_master *master, struct spi_device *spi,
+ struct spi_transfer *transfer);
/* gpio chip select */
int *cs_gpios;
@@ -428,12 +455,15 @@ extern int spi_master_resume(struct spi_master *master);
/* Calls the driver make to interact with the message queue */
extern struct spi_message *spi_get_next_queued_message(struct spi_master *master);
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 int spi_register_master(struct spi_master *master);
+extern int devm_spi_register_master(struct device *dev,
+ struct spi_master *master);
extern void spi_unregister_master(struct spi_master *master);
extern struct spi_master *spi_busnum_to_master(u16 busnum);
@@ -823,6 +853,33 @@ static inline ssize_t spi_w8r16(struct spi_device *spi, u8 cmd)
return (status < 0) ? status : result;
}
+/**
+ * spi_w8r16be - SPI synchronous 8 bit write followed by 16 bit big-endian read
+ * @spi: device with which data will be exchanged
+ * @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.
+ *
+ */
+static inline ssize_t spi_w8r16be(struct spi_device *spi, u8 cmd)
+
+{
+ ssize_t status;
+ __be16 result;
+
+ status = spi_write_then_read(spi, &cmd, 1, &result, 2);
+ if (status < 0)
+ return status;
+
+ return be16_to_cpu(result);
+}
+
/*---------------------------------------------------------------------------*/
/*