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-rw-r--r--include/linux/spi/spi.h8
-rw-r--r--include/linux/spi/spi_bitbang.h6
2 files changed, 14 insertions, 0 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index b05f146..caa4665 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -31,6 +31,7 @@ extern struct bus_type spi_bus_type;
* @master: SPI controller used with the device.
* @max_speed_hz: Maximum clock rate to be used with this chip
* (on this board); may be changed by the device's driver.
+ * The spi_transfer.speed_hz can override this for each transfer.
* @chip-select: Chipselect, distinguishing chips handled by "master".
* @mode: The spi mode defines how data is clocked out and in.
* This may be changed by the device's driver.
@@ -38,6 +39,7 @@ extern struct bus_type spi_bus_type;
* like eight or 12 bits are common. In-memory wordsizes are
* powers of two bytes (e.g. 20 bit samples use 32 bits).
* This may be changed by the device's driver.
+ * The spi_transfer.bits_per_word can override this for each transfer.
* @irq: Negative, or the number passed to request_irq() to receive
* interrupts from this device.
* @controller_state: Controller's runtime state
@@ -268,6 +270,10 @@ extern struct spi_master *spi_busnum_to_master(u16 busnum);
* @tx_dma: DMA address of tx_buf, if spi_message.is_dma_mapped
* @rx_dma: DMA address of rx_buf, if spi_message.is_dma_mapped
* @len: size of rx and tx buffers (in bytes)
+ * @speed_hz: Select a speed other then the device default for this
+ * transfer. If 0 the default (from spi_device) is used.
+ * @bits_per_word: select a bits_per_word other then the device default
+ * for this transfer. If 0 the default (from spi_device) is used.
* @cs_change: affects chipselect after this transfer completes
* @delay_usecs: microseconds to delay after this transfer before
* (optionally) changing the chipselect status, then starting
@@ -322,7 +328,9 @@ struct spi_transfer {
dma_addr_t rx_dma;
unsigned cs_change:1;
+ u8 bits_per_word;
u16 delay_usecs;
+ u32 speed_hz;
struct list_head transfer_list;
};
diff --git a/include/linux/spi/spi_bitbang.h b/include/linux/spi/spi_bitbang.h
index c961fe9..c954557 100644
--- a/include/linux/spi/spi_bitbang.h
+++ b/include/linux/spi/spi_bitbang.h
@@ -30,6 +30,12 @@ struct spi_bitbang {
struct spi_master *master;
+ /* setup_transfer() changes clock and/or wordsize to match settings
+ * for this transfer; zeroes restore defaults from spi_device.
+ */
+ int (*setup_transfer)(struct spi_device *spi,
+ struct spi_transfer *t);
+
void (*chipselect)(struct spi_device *spi, int is_on);
#define BITBANG_CS_ACTIVE 1 /* normally nCS, active low */
#define BITBANG_CS_INACTIVE 0
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