diff options
| author | Vishwaroop A <va@nvidia.com> | 2025-04-16 11:06:05 +0000 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2025-04-24 14:30:57 +0100 |
| commit | c283fcdc4e2b89678c171691fd26f576139fc256 (patch) | |
| tree | 3d26daf176370530757350ef1af0e9e150ada132 /drivers/spi | |
| parent | d8966b65413390d1b5b706886987caac05fbe024 (diff) | |
spi: tegra210-quad: Update dummy sequence configuration
Adding support for the dummy sequence configuration. The dummy sequence
introduces a delay between the command and the data phases of a
transfer. This delay, measured in clock cycles, allows the slave
device to prepare for data transmission, ensuring data integrity and
proper synchronization.
Signed-off-by: Vishwaroop A <va@nvidia.com>
Link: https://patch.msgid.link/20250416110606.2737315-6-va@nvidia.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-tegra210-quad.c | 31 |
1 files changed, 26 insertions, 5 deletions
diff --git a/drivers/spi/spi-tegra210-quad.c b/drivers/spi/spi-tegra210-quad.c index 159fbbfd4a38..04f41e92c1e2 100644 --- a/drivers/spi/spi-tegra210-quad.c +++ b/drivers/spi/spi-tegra210-quad.c @@ -22,6 +22,7 @@ #include <linux/spi/spi.h> #include <linux/acpi.h> #include <linux/property.h> +#include <linux/sizes.h> #define QSPI_COMMAND1 0x000 #define QSPI_BIT_LENGTH(x) (((x) & 0x1f) << 0) @@ -156,10 +157,14 @@ #define DATA_DIR_RX BIT(1) #define QSPI_DMA_TIMEOUT (msecs_to_jiffies(1000)) -#define DEFAULT_QSPI_DMA_BUF_LEN (64 * 1024) -#define CMD_TRANSFER 0 -#define ADDR_TRANSFER 1 -#define DATA_TRANSFER 2 +#define DEFAULT_QSPI_DMA_BUF_LEN SZ_64K + +enum tegra_qspi_transfer_type { + CMD_TRANSFER = 0, + ADDR_TRANSFER = 1, + DUMMY_TRANSFER = 2, + DATA_TRANSFER = 3 +}; struct tegra_qspi_soc_data { bool has_dma; @@ -1085,6 +1090,13 @@ static int tegra_qspi_combined_seq_xfer(struct tegra_qspi *tqspi, xfer->len); address_value = *((const u32 *)(xfer->tx_buf)); break; + case DUMMY_TRANSFER: + if (xfer->dummy_data) { + tqspi->dummy_cycles = xfer->len * 8 / xfer->tx_nbits; + break; + } + transfer_phase++; + fallthrough; case DATA_TRANSFER: /* Program Command, Address value in register */ tegra_qspi_writel(tqspi, cmd_value, QSPI_CMB_SEQ_CMD); @@ -1292,7 +1304,9 @@ static bool tegra_qspi_validate_cmb_seq(struct tegra_qspi *tqspi, list_for_each_entry(xfer, &msg->transfers, transfer_list) { transfer_count++; } - if (!tqspi->soc_data->cmb_xfer_capable || transfer_count != 3) + if (!tqspi->soc_data->cmb_xfer_capable) + return false; + if (transfer_count > 4 || transfer_count < 3) return false; xfer = list_first_entry(&msg->transfers, typeof(*xfer), transfer_list); @@ -1302,6 +1316,13 @@ static bool tegra_qspi_validate_cmb_seq(struct tegra_qspi *tqspi, if (xfer->len > 4 || xfer->len < 3) return false; xfer = list_next_entry(xfer, transfer_list); + if (transfer_count == 4) { + if (xfer->dummy_data != 1) + return false; + if ((xfer->len * 8 / xfer->tx_nbits) > QSPI_DUMMY_CYCLES_MAX) + return false; + xfer = list_next_entry(xfer, transfer_list); + } if (!tqspi->soc_data->has_dma && xfer->len > (QSPI_FIFO_DEPTH << 2)) return false; |