diff options
| -rw-r--r-- | drivers/spi/spi.c | 7 | ||||
| -rw-r--r-- | include/linux/spi/spi.h | 10 |
2 files changed, 17 insertions, 0 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 00b81d81c09a..b0e7702951fe 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -4094,6 +4094,13 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message) if (__spi_validate_bits_per_word(ctlr, xfer->bits_per_word)) return -EINVAL; + /* DDR mode is supported only if controller has dtr_caps=true. + * default considered as SDR mode for SPI and QSPI controller. + * Note: This is applicable only to QSPI controller. + */ + if (xfer->dtr_mode && !ctlr->dtr_caps) + return -EINVAL; + /* * SPI transfer length should be multiple of SPI word size * where SPI word size should be power-of-two multiple. diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index e10f0ebb8250..834a09bd8ccc 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -508,6 +508,8 @@ extern struct spi_device *spi_new_ancillary_device(struct spi_device *spi, u8 ch * found. * @put_offload: release the offload instance acquired by @get_offload. * @mem_caps: controller capabilities for the handling of memory operations. + * @dtr_caps: true if controller has dtr(single/dual transfer rate) capability. + * QSPI based controller should fill this based on controller's capability. * @unprepare_message: undo any work done by prepare_message(). * @target_abort: abort the ongoing transfer request on an SPI target controller * @cs_gpiods: Array of GPIO descriptors to use as chip select lines; one per CS @@ -751,6 +753,9 @@ struct spi_controller { const struct spi_controller_mem_ops *mem_ops; const struct spi_controller_mem_caps *mem_caps; + /* SPI or QSPI controller can set to true if supports SDR/DDR transfer rate */ + bool dtr_caps; + struct spi_offload *(*get_offload)(struct spi_device *spi, const struct spi_offload_config *config); void (*put_offload)(struct spi_offload *offload); @@ -1003,6 +1008,7 @@ struct spi_res { * processed the word, i.e. the "pre" timestamp should be taken before * transmitting the "pre" word, and the "post" timestamp after receiving * transmit confirmation from the controller for the "post" word. + * @dtr_mode: true if supports double transfer rate. * @timestamped: true if the transfer has been timestamped * @error: Error status logged by SPI controller driver. * @@ -1054,6 +1060,9 @@ struct spi_res { * two should both be set. User can set transfer mode with SPI_NBITS_SINGLE(1x) * SPI_NBITS_DUAL(2x) and SPI_NBITS_QUAD(4x) to support these three transfer. * + * User may also set dtr_mode to true to use dual transfer mode if desired. if + * not, default considered as single transfer mode. + * * The code that submits an spi_message (and its spi_transfers) * to the lower layers is responsible for managing its memory. * Zero-initialize every field you don't set up explicitly, to @@ -1088,6 +1097,7 @@ struct spi_transfer { unsigned tx_nbits:4; unsigned rx_nbits:4; unsigned timestamped:1; + bool dtr_mode; #define SPI_NBITS_SINGLE 0x01 /* 1-bit transfer */ #define SPI_NBITS_DUAL 0x02 /* 2-bit transfer */ #define SPI_NBITS_QUAD 0x04 /* 4-bit transfer */ |