diff options
Diffstat (limited to 'include/linux/spi/spi.h')
-rw-r--r-- | include/linux/spi/spi.h | 25 |
1 files changed, 15 insertions, 10 deletions
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index 8c62ba74dd91..4203c66d8803 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -75,6 +75,7 @@ struct spi_device { struct spi_master *master; u32 max_speed_hz; u8 chip_select; + u8 bits_per_word; u16 mode; #define SPI_CPHA 0x01 /* clock phase */ #define SPI_CPOL 0x02 /* clock polarity */ @@ -92,7 +93,6 @@ struct spi_device { #define SPI_TX_QUAD 0x200 /* transmit with 4 wires */ #define SPI_RX_DUAL 0x400 /* receive with 2 wires */ #define SPI_RX_QUAD 0x800 /* receive with 4 wires */ - u8 bits_per_word; int irq; void *controller_state; void *controller_data; @@ -273,19 +273,24 @@ static inline void spi_unregister_driver(struct spi_driver *sdrv) * message while queuing transfers that arrive in the meantime. When the * driver is finished with this message, it must call * spi_finalize_current_message() so the subsystem can issue the next - * transfer + * message * @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 + * @set_cs: set the logic level of the chip select line. 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 + * @transfer_one: transfer a single spi_transfer. + * - return 0 if the transfer is finished, + * - return 1 if the transfer is still in progress. When + * the driver is finished with this transfer it must + * call spi_finalize_current_transfer() so the subsystem + * can issue the next transfer. Note: transfer_one and + * transfer_one_message are mutually exclusive; when both + * are set, the generic subsystem does not call your + * transfer_one callback. * @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 @@ -576,8 +581,8 @@ struct spi_transfer { dma_addr_t rx_dma; unsigned cs_change:1; - u8 tx_nbits; - u8 rx_nbits; + unsigned tx_nbits:3; + unsigned rx_nbits:3; #define SPI_NBITS_SINGLE 0x01 /* 1bit transfer */ #define SPI_NBITS_DUAL 0x02 /* 2bits transfer */ #define SPI_NBITS_QUAD 0x04 /* 4bits transfer */ @@ -847,7 +852,7 @@ static inline ssize_t spi_w8r16(struct spi_device *spi, u8 cmd) ssize_t status; u16 result; - status = spi_write_then_read(spi, &cmd, 1, (u8 *) &result, 2); + status = spi_write_then_read(spi, &cmd, 1, &result, 2); /* return negative errno or unsigned value */ return (status < 0) ? status : result; |