diff options
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-mem.c | 45 |
1 files changed, 40 insertions, 5 deletions
diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c index 3579b7d7db5..db44a7b26eb 100644 --- a/drivers/spi/spi-mem.c +++ b/drivers/spi/spi-mem.c @@ -120,18 +120,21 @@ static int spi_check_buswidth_req(struct spi_slave *slave, u8 buswidth, bool tx) return 0; case 2: - if ((tx && (mode & (SPI_TX_DUAL | SPI_TX_QUAD))) || - (!tx && (mode & (SPI_RX_DUAL | SPI_RX_QUAD)))) + if ((tx && + (mode & (SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL))) || + (!tx && + (mode & (SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL)))) return 0; break; case 4: - if ((tx && (mode & SPI_TX_QUAD)) || - (!tx && (mode & SPI_RX_QUAD))) + if ((tx && (mode & (SPI_TX_QUAD | SPI_TX_OCTAL))) || + (!tx && (mode & (SPI_RX_QUAD | SPI_RX_OCTAL)))) return 0; break; + case 8: if ((tx && (mode & SPI_TX_OCTAL)) || (!tx && (mode & SPI_RX_OCTAL))) @@ -300,7 +303,7 @@ int spi_mem_exec_op(struct spi_slave *slave, const struct spi_mem_op *op) * read path) and expect the core to use the regular SPI * interface in other cases. */ - if (!ret || ret != -ENOTSUPP) { + if (!ret || (ret != -ENOTSUPP && ret != -EOPNOTSUPP)) { spi_release_bus(slave); return ret; } @@ -496,6 +499,38 @@ int spi_mem_adjust_op_size(struct spi_slave *slave, struct spi_mem_op *op) } EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size); +/** + * spi_mem_calc_op_duration() - Derives the theoretical length (in cpu cycles) + * of an operation. This helps finding the best + * variant among a list of possible choices. + * @op: the operation to benchmark + * + * Some chips have per-op frequency limitations, PCBs usually have their own + * limitations as well, and controllers can support dual, quad or even octal + * modes, sometimes in DTR. All these combinations make it impossible to + * statically list the best combination for all situations. If we want something + * accurate, all these combinations should be rated (eg. with a time estimate) + * and the best pick should be taken based on these calculations. + * + * Returns a estimate for the time this op would take. + */ +u64 spi_mem_calc_op_duration(struct spi_mem_op *op) +{ + u64 ncycles = 0; + + ncycles += ((op->cmd.nbytes * 8) / op->cmd.buswidth) / (op->cmd.dtr ? 2 : 1); + ncycles += ((op->addr.nbytes * 8) / op->addr.buswidth) / (op->addr.dtr ? 2 : 1); + + /* Dummy bytes are optional for some SPI flash memory operations */ + if (op->dummy.nbytes) + ncycles += ((op->dummy.nbytes * 8) / op->dummy.buswidth) / (op->dummy.dtr ? 2 : 1); + + ncycles += ((op->data.nbytes * 8) / op->data.buswidth) / (op->data.dtr ? 2 : 1); + + return ncycles; +} +EXPORT_SYMBOL_GPL(spi_mem_calc_op_duration); + static ssize_t spi_mem_no_dirmap_read(struct spi_mem_dirmap_desc *desc, u64 offs, size_t len, void *buf) { |