diff options
| author | Lars Povlsen <lars.povlsen@microchip.com> | 2020-08-24 22:30:05 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2020-09-08 16:15:36 +0100 |
| commit | bac70b54ecb53b3d5af862dd4fcbaaad8f34ed23 (patch) | |
| tree | b8c9116cf9dd75cc082f5027f72b65051f1a638a /drivers/spi/spi-dw.h | |
| parent | 2abaad678575acd54e9939e1174becd82ecc884b (diff) | |
spi: dw: Add support for RX sample delay register
This add support for the RX_SAMPLE_DLY register. If enabled in the
Designware IP, it allows tuning of the rx data signal by means of an
internal rx sample fifo.
The register is controlled by the rx-sample-delay-ns DT property,
which is defined per SPI slave as well on controller level.
The controller level rx-sample-delay-ns will apply to all slaves
without the property explicitly defined.
The register is located at offset 0xf0, and if the option is not
enabled in the IP, changing the register will have no effect. The
register will only be written if any slave defines a nonzero value
(after scaling by the clock period).
Signed-off-by: Lars Povlsen <lars.povlsen@microchip.com>
Link: https://lore.kernel.org/r/20200824203010.2033-2-lars.povlsen@microchip.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-dw.h')
| -rw-r--r-- | drivers/spi/spi-dw.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/spi/spi-dw.h b/drivers/spi/spi-dw.h index 151ba316619e..90dfd21622d6 100644 --- a/drivers/spi/spi-dw.h +++ b/drivers/spi/spi-dw.h @@ -34,6 +34,7 @@ #define DW_SPI_IDR 0x58 #define DW_SPI_VERSION 0x5c #define DW_SPI_DR 0x60 +#define DW_SPI_RX_SAMPLE_DLY 0xf0 #define DW_SPI_CS_OVERRIDE 0xf4 /* Bit fields in CTRLR0 */ @@ -140,6 +141,8 @@ struct dw_spi { u8 n_bytes; /* current is a 1/2 bytes op */ irqreturn_t (*transfer_handler)(struct dw_spi *dws); u32 current_freq; /* frequency in hz */ + u32 cur_rx_sample_dly; + u32 def_rx_sample_dly_ns; /* DMA info */ struct dma_chan *txchan; |