diff options
Diffstat (limited to 'drivers/spi/spi-fsl-espi.c')
| -rw-r--r-- | drivers/spi/spi-fsl-espi.c | 77 |
1 files changed, 63 insertions, 14 deletions
diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c index 189ab36b787f..e93892dca90a 100644 --- a/drivers/spi/spi-fsl-espi.c +++ b/drivers/spi/spi-fsl-espi.c @@ -102,6 +102,9 @@ struct fsl_espi { struct spi_transfer *tx_t; unsigned int tx_pos; bool tx_done; + struct spi_transfer *rx_t; + unsigned int rx_pos; + bool rx_done; bool swab; unsigned int rx_len; @@ -125,6 +128,11 @@ static inline u32 fsl_espi_read_reg(struct fsl_espi *espi, int offset) return ioread32be(espi->reg_base + offset); } +static inline u16 fsl_espi_read_reg16(struct fsl_espi *espi, int offset) +{ + return ioread16(espi->reg_base + offset); +} + static inline u8 fsl_espi_read_reg8(struct fsl_espi *espi, int offset) { return ioread8(espi->reg_base + offset); @@ -328,19 +336,53 @@ start: static void fsl_espi_read_rx_fifo(struct fsl_espi *espi, u32 events) { u32 rx_fifo_avail = SPIE_RXCNT(events); + unsigned int rx_left; + void *rx_buf; - while (rx_fifo_avail >= min(4U, espi->rx_len) && espi->rx_len) - if (espi->rx_len >= 4) { - *(u32 *)espi->rx = fsl_espi_read_reg(espi, ESPI_SPIRF); - espi->rx += 4; - espi->rx_len -= 4; +start: + rx_left = espi->rx_t->len - espi->rx_pos; + rx_buf = espi->rx_t->rx_buf; + while (rx_fifo_avail >= min(4U, rx_left) && rx_left) { + if (rx_left >= 4) { + u32 val = fsl_espi_read_reg(espi, ESPI_SPIRF); + + if (rx_buf && espi->swab) + *(u32 *)(rx_buf + espi->rx_pos) = swahb32(val); + else if (rx_buf) + *(u32 *)(rx_buf + espi->rx_pos) = val; + espi->rx_pos += 4; + rx_left -= 4; rx_fifo_avail -= 4; + } else if (rx_left >= 2 && rx_buf && espi->swab) { + u16 val = fsl_espi_read_reg16(espi, ESPI_SPIRF); + + *(u16 *)(rx_buf + espi->rx_pos) = swab16(val); + espi->rx_pos += 2; + rx_left -= 2; + rx_fifo_avail -= 2; } else { - *(u8 *)espi->rx = fsl_espi_read_reg8(espi, ESPI_SPIRF); - espi->rx += 1; - espi->rx_len -= 1; + u8 val = fsl_espi_read_reg8(espi, ESPI_SPIRF); + + if (rx_buf) + *(u8 *)(rx_buf + espi->rx_pos) = val; + espi->rx_pos += 1; + rx_left -= 1; rx_fifo_avail -= 1; } + } + + if (!rx_left) { + if (list_is_last(&espi->rx_t->transfer_list, + espi->m_transfers)) { + espi->rx_done = true; + return; + } + espi->rx_t = list_next_entry(espi->rx_t, transfer_list); + espi->rx_pos = 0; + /* continue with next transfer if rx fifo is not empty */ + if (rx_fifo_avail) + goto start; + } } static void fsl_espi_setup_transfer(struct spi_device *spi, @@ -375,6 +417,7 @@ static void fsl_espi_setup_transfer(struct spi_device *spi, static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t) { struct fsl_espi *espi = spi_master_get_devdata(spi->master); + unsigned int rx_len = t->len; u32 mask, spcom; int ret; @@ -395,6 +438,7 @@ static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t) spcom |= SPCOM_RXSKIP(espi->rxskip); espi->tx_len = espi->rxskip; espi->rx_len = t->len - espi->rxskip; + rx_len = t->len - espi->rxskip; espi->rx = t->rx_buf + espi->rxskip; if (t->rx_nbits == SPI_NBITS_DUAL) spcom |= SPCOM_DO; @@ -404,7 +448,7 @@ static int fsl_espi_bufs(struct spi_device *spi, struct spi_transfer *t) /* enable interrupts */ mask = SPIM_DON; - if (espi->rx_len > FSL_ESPI_FIFO_SIZE) + if (rx_len > FSL_ESPI_FIFO_SIZE) mask |= SPIM_RXT; fsl_espi_write_reg(espi, ESPI_SPIM, mask); @@ -438,6 +482,10 @@ static int fsl_espi_trans(struct spi_message *m, struct spi_transfer *trans) transfer_list); espi->tx_pos = 0; espi->tx_done = false; + espi->rx_t = list_first_entry(&m->transfers, struct spi_transfer, + transfer_list); + espi->rx_pos = 0; + espi->rx_done = false; espi->rxskip = fsl_espi_check_rxskip_mode(m); if (trans->rx_nbits == SPI_NBITS_DUAL && !espi->rxskip) { @@ -445,6 +493,10 @@ static int fsl_espi_trans(struct spi_message *m, struct spi_transfer *trans) return -EINVAL; } + /* In RXSKIP mode skip first transfer for reads */ + if (espi->rxskip) + espi->rx_t = list_next_entry(espi->rx_t, transfer_list); + fsl_espi_copy_to_buf(m, espi); fsl_espi_setup_transfer(spi, trans); @@ -453,9 +505,6 @@ static int fsl_espi_trans(struct spi_message *m, struct spi_transfer *trans) if (trans->delay_usecs) udelay(trans->delay_usecs); - if (!ret) - fsl_espi_copy_from_buf(m, espi); - return ret; } @@ -556,13 +605,13 @@ static void fsl_espi_cleanup(struct spi_device *spi) static void fsl_espi_cpu_irq(struct fsl_espi *espi, u32 events) { - if (espi->rx_len) + if (!espi->rx_done) fsl_espi_read_rx_fifo(espi, events); if (!espi->tx_done) fsl_espi_fill_tx_fifo(espi, events); - if (!espi->tx_done || espi->rx_len) + if (!espi->tx_done || !espi->rx_done) return; /* we're done, but check for errors before returning */ |