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-rw-r--r--include/linux/spi/spi.h145
1 files changed, 145 insertions, 0 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 53be3a4c60cb..857a9a1d82b5 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -25,6 +25,7 @@
struct dma_chan;
struct spi_master;
struct spi_transfer;
+struct spi_flash_read_message;
/*
* INTERFACES between SPI master-side drivers and SPI infrastructure.
@@ -53,6 +54,10 @@ extern struct bus_type spi_bus_type;
*
* @transfer_bytes_histo:
* transfer bytes histogramm
+ *
+ * @transfers_split_maxsize:
+ * number of transfers that have been split because of
+ * maxsize limit
*/
struct spi_statistics {
spinlock_t lock; /* lock for the whole structure */
@@ -72,6 +77,8 @@ struct spi_statistics {
#define SPI_STATISTICS_HISTO_SIZE 17
unsigned long transfer_bytes_histo[SPI_STATISTICS_HISTO_SIZE];
+
+ unsigned long transfers_split_maxsize;
};
void spi_statistics_add_transfer_stats(struct spi_statistics *stats,
@@ -303,6 +310,8 @@ 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
+ * @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.
* @bus_lock_spinlock: spinlock for SPI bus locking
* @bus_lock_mutex: mutex for SPI bus locking
* @bus_lock_flag: indicates that the SPI bus is locked for exclusive use
@@ -361,6 +370,8 @@ 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().
+ * @spi_flash_read: to support spi-controller hardwares that provide
+ * accelerated interface to read from flash devices.
* @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).
@@ -369,6 +380,9 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv)
* @dma_rx: DMA receive channel
* @dummy_rx: dummy receive buffer for full-duplex devices
* @dummy_tx: dummy transmit buffer for full-duplex devices
+ * @fw_translate_cs: If the boot firmware uses different numbering scheme
+ * what Linux expects, this optional hook can be used to translate
+ * between the two.
*
* Each SPI master controller can communicate with one or more @spi_device
* children. These make a small bus, sharing MOSI, MISO and SCK signals
@@ -513,6 +527,8 @@ struct spi_master {
struct spi_message *message);
int (*unprepare_message)(struct spi_master *master,
struct spi_message *message);
+ int (*spi_flash_read)(struct spi_device *spi,
+ struct spi_flash_read_message *msg);
/*
* These hooks are for drivers that use a generic implementation
@@ -537,6 +553,8 @@ struct spi_master {
/* dummy data for full duplex devices */
void *dummy_rx;
void *dummy_tx;
+
+ int (*fw_translate_cs)(struct spi_master *master, unsigned cs);
};
static inline void *spi_master_get_devdata(struct spi_master *master)
@@ -582,6 +600,38 @@ extern void spi_unregister_master(struct spi_master *master);
extern struct spi_master *spi_busnum_to_master(u16 busnum);
+/*
+ * SPI resource management while processing a SPI message
+ */
+
+typedef void (*spi_res_release_t)(struct spi_master *master,
+ struct spi_message *msg,
+ void *res);
+
+/**
+ * struct spi_res - spi resource management structure
+ * @entry: list entry
+ * @release: release code called prior to freeing this resource
+ * @data: extra data allocated for the specific use-case
+ *
+ * this is based on ideas from devres, but focused on life-cycle
+ * management during spi_message processing
+ */
+struct spi_res {
+ struct list_head entry;
+ spi_res_release_t release;
+ unsigned long long data[]; /* guarantee ull alignment */
+};
+
+extern void *spi_res_alloc(struct spi_device *spi,
+ spi_res_release_t release,
+ size_t size, gfp_t gfp);
+extern void spi_res_add(struct spi_message *message, void *res);
+extern void spi_res_free(void *res);
+
+extern void spi_res_release(struct spi_master *master,
+ struct spi_message *message);
+
/*---------------------------------------------------------------------------*/
/*
@@ -720,6 +770,7 @@ struct spi_transfer {
* @status: zero for success, else negative errno
* @queue: for use by whichever driver currently owns the message
* @state: for use by whichever driver currently owns the message
+ * @resources: for resource management when the spi message is processed
*
* A @spi_message is used to execute an atomic sequence of data transfers,
* each represented by a struct spi_transfer. The sequence is "atomic"
@@ -766,11 +817,15 @@ struct spi_message {
*/
struct list_head queue;
void *state;
+
+ /* list of spi_res reources when the spi message is processed */
+ struct list_head resources;
};
static inline void spi_message_init_no_memset(struct spi_message *m)
{
INIT_LIST_HEAD(&m->transfers);
+ INIT_LIST_HEAD(&m->resources);
}
static inline void spi_message_init(struct spi_message *m)
@@ -854,6 +909,60 @@ spi_max_transfer_size(struct spi_device *spi)
/*---------------------------------------------------------------------------*/
+/* SPI transfer replacement methods which make use of spi_res */
+
+struct spi_replaced_transfers;
+typedef void (*spi_replaced_release_t)(struct spi_master *master,
+ struct spi_message *msg,
+ struct spi_replaced_transfers *res);
+/**
+ * struct spi_replaced_transfers - structure describing the spi_transfer
+ * replacements that have occurred
+ * so that they can get reverted
+ * @release: some extra release code to get executed prior to
+ * relasing this structure
+ * @extradata: pointer to some extra data if requested or NULL
+ * @replaced_transfers: transfers that have been replaced and which need
+ * to get restored
+ * @replaced_after: the transfer after which the @replaced_transfers
+ * are to get re-inserted
+ * @inserted: number of transfers inserted
+ * @inserted_transfers: array of spi_transfers of array-size @inserted,
+ * that have been replacing replaced_transfers
+ *
+ * note: that @extradata will point to @inserted_transfers[@inserted]
+ * if some extra allocation is requested, so alignment will be the same
+ * as for spi_transfers
+ */
+struct spi_replaced_transfers {
+ spi_replaced_release_t release;
+ void *extradata;
+ struct list_head replaced_transfers;
+ struct list_head *replaced_after;
+ size_t inserted;
+ struct spi_transfer inserted_transfers[];
+};
+
+extern struct spi_replaced_transfers *spi_replace_transfers(
+ struct spi_message *msg,
+ struct spi_transfer *xfer_first,
+ size_t remove,
+ size_t insert,
+ spi_replaced_release_t release,
+ size_t extradatasize,
+ gfp_t gfp);
+
+/*---------------------------------------------------------------------------*/
+
+/* SPI transfer transformation methods */
+
+extern int spi_split_transfers_maxsize(struct spi_master *master,
+ struct spi_message *msg,
+ size_t maxsize,
+ gfp_t gfp);
+
+/*---------------------------------------------------------------------------*/
+
/* All these synchronous SPI transfer routines are utilities layered
* over the core async transfer primitive. Here, "synchronous" means
* they will sleep uninterruptibly until the async transfer completes.
@@ -1019,6 +1128,42 @@ static inline ssize_t spi_w8r16be(struct spi_device *spi, u8 cmd)
return be16_to_cpu(result);
}
+/**
+ * struct spi_flash_read_message - flash specific information for
+ * spi-masters that provide accelerated flash read interfaces
+ * @buf: buffer to read data
+ * @from: offset within the flash from where data is to be read
+ * @len: length of data to be read
+ * @retlen: actual length of data read
+ * @read_opcode: read_opcode to be used to communicate with flash
+ * @addr_width: number of address bytes
+ * @dummy_bytes: number of dummy bytes
+ * @opcode_nbits: number of lines to send opcode
+ * @addr_nbits: number of lines to send address
+ * @data_nbits: number of lines for data
+ */
+struct spi_flash_read_message {
+ void *buf;
+ loff_t from;
+ size_t len;
+ size_t retlen;
+ u8 read_opcode;
+ u8 addr_width;
+ u8 dummy_bytes;
+ u8 opcode_nbits;
+ u8 addr_nbits;
+ u8 data_nbits;
+};
+
+/* SPI core interface for flash read support */
+static inline bool spi_flash_read_supported(struct spi_device *spi)
+{
+ return spi->master->spi_flash_read ? true : false;
+}
+
+int spi_flash_read(struct spi_device *spi,
+ struct spi_flash_read_message *msg);
+
/*---------------------------------------------------------------------------*/
/*