diff options
Diffstat (limited to 'src/drivers/spi/spi_flash.c')
| -rw-r--r-- | src/drivers/spi/spi_flash.c | 47 |
1 files changed, 15 insertions, 32 deletions
diff --git a/src/drivers/spi/spi_flash.c b/src/drivers/spi/spi_flash.c index 3b4272b709..a0e310554a 100644 --- a/src/drivers/spi/spi_flash.c +++ b/src/drivers/spi/spi_flash.c @@ -32,47 +32,30 @@ static void spi_flash_addr(u32 addr, u8 *cmd) cmd[3] = addr >> 0; } -/* - * If atomic sequencing is used, the cycle type is known to the SPI - * controller so that it can perform consecutive transfers and arbitrate - * automatically. Otherwise the SPI controller transfers whatever the - * user requests immediately, without regard to sequence. Atomic - * sequencing is commonly used on x86 platforms. - * - * SPI flash commands are simple two-step sequences. The command byte is - * always written first and may be followed by an address. Then data is - * either read or written. For atomic sequencing we'll pass everything into - * spi_xfer() at once and let the controller handle the details. Otherwise - * we will write all output bytes first and then read if necessary. - * - * FIXME: This really should be abstracted better, but that will - * require overhauling the entire SPI infrastructure. - */ static int do_spi_flash_cmd(const struct spi_slave *spi, const void *dout, size_t bytes_out, void *din, size_t bytes_in) { int ret = 1; + /* + * SPI flash requires command-response kind of behavior. Thus, two + * separate SPI vectors are required -- first to transmit dout and other + * to receive in din. If some specialized SPI flash controllers + * (e.g. x86) can perform both command and response together, it should + * be handled at SPI flash controller driver level. + */ + struct spi_op vectors[] = { + [0] = { .dout = dout, .bytesout = bytes_out, + .din = NULL, .bytesin = 0, }, + [1] = { .dout = NULL, .bytesout = 0, + .din = din, .bytesin = bytes_in }, + }; if (spi_claim_bus(spi)) return ret; -#if CONFIG_SPI_ATOMIC_SEQUENCING == 1 - if (spi_xfer(spi, dout, bytes_out, din, bytes_in) < 0) - goto done; -#else - if (dout && bytes_out) { - if (spi_xfer(spi, dout, bytes_out, NULL, 0) < 0) - goto done; - } - - if (din && bytes_in) { - if (spi_xfer(spi, NULL, 0, din, bytes_in) < 0) - goto done; - } -#endif + if (spi_xfer_vector(spi, vectors, ARRAY_SIZE(vectors)) == 0) + ret = 0; - ret = 0; -done: spi_release_bus(spi); return ret; } |