diff options
| -rw-r--r-- | src/lpc/ao_spi_lpc.c | 133 |
1 files changed, 25 insertions, 108 deletions
diff --git a/src/lpc/ao_spi_lpc.c b/src/lpc/ao_spi_lpc.c index 5a358919..f091c89c 100644 --- a/src/lpc/ao_spi_lpc.c +++ b/src/lpc/ao_spi_lpc.c @@ -19,130 +19,56 @@ static uint8_t ao_spi_mutex[LPC_NUM_SPI]; -struct ao_lpc_ssp_state { - int tx_count; - const uint8_t *tx; - int tx_inc; - int rx_count; - uint8_t *rx; - int rx_inc; -}; - -static struct ao_lpc_ssp_state ao_lpc_ssp_state[LPC_NUM_SPI]; - static struct lpc_ssp * const ao_lpc_ssp[LPC_NUM_SPI] = { &lpc_ssp0, &lpc_ssp1 }; -static inline void -ao_lpc_ssp_recv(struct lpc_ssp *lpc_ssp, struct ao_lpc_ssp_state *state) -{ - while ((lpc_ssp->sr & (1 << LPC_SSP_SR_RNE)) && - state->rx_count) - { - /* RX ready, read a byte */ - *state->rx = lpc_ssp->dr; - state->rx += state->rx_inc; - state->rx_count--; - } -} - -static void -ao_lpc_ssp_isr(struct lpc_ssp *lpc_ssp, struct ao_lpc_ssp_state *state) -{ - ao_lpc_ssp_recv(lpc_ssp, state); - while ((lpc_ssp->sr & (1 << LPC_SSP_SR_TNF)) && - state->tx_count) - { - /* TX ready, write a byte */ - lpc_ssp->dr = *state->tx; - state->tx += state->tx_inc; - state->tx_count--; - ao_lpc_ssp_recv(lpc_ssp, state); - } - if (!state->rx_count) { - lpc_ssp->imsc &= ~(1 << LPC_SSP_IMSC_TXIM); - ao_wakeup(state); - } -} - -void -lpc_ssp0_isr(void) -{ - ao_lpc_ssp_isr(&lpc_ssp0, &ao_lpc_ssp_state[0]); -} - -void -lpc_ssp1_isr(void) -{ - ao_lpc_ssp_isr(&lpc_ssp1, &ao_lpc_ssp_state[1]); -} - -static void -ao_spi_run(struct lpc_ssp *lpc_ssp, struct ao_lpc_ssp_state *state) -{ - ao_arch_block_interrupts(); - lpc_ssp->imsc = (1 << LPC_SSP_IMSC_TXIM); - while (state->rx_count) - ao_sleep(state); - ao_arch_release_interrupts(); -} - -static uint8_t ao_spi_tx_dummy = 0xff; -static uint8_t ao_spi_rx_dummy; +#define spi_loop(len, put, get) do { \ + while (len--) { \ + /* send a byte */ \ + lpc_ssp->dr = put; \ + /* wait for the received byte to appear */ \ + while ((lpc_ssp->sr & (1 << LPC_SSP_SR_RNE)) == 0) \ + ; \ + /* receive a byte */ \ + get lpc_ssp->dr; \ + } \ + /* Wait for the SSP to go idle (it already should be) */ \ + while (lpc_ssp->sr & (1 << LPC_SSP_SR_BSY)); \ + } while (0) void ao_spi_send(const void *block, uint16_t len, uint8_t id) { struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id]; - struct ao_lpc_ssp_state *state = &ao_lpc_ssp_state[id]; - - state->tx_count = state->rx_count = len; - state->tx = block; - state->tx_inc = 1; - state->rx = &ao_spi_rx_dummy; - state->rx_inc = 0; - ao_spi_run(lpc_ssp, state); + const uint8_t *o = block; + + spi_loop(len, *o++, (void)); } void ao_spi_send_fixed(uint8_t value, uint16_t len, uint8_t id) { struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id]; - struct ao_lpc_ssp_state *state = &ao_lpc_ssp_state[id]; - - state->tx_count = state->rx_count = len; - state->tx = &value; - state->tx_inc = 0; - state->rx = &ao_spi_rx_dummy; - state->rx_inc = 0; - ao_spi_run(lpc_ssp, state); + + spi_loop(len, value, (void)); } void ao_spi_recv(void *block, uint16_t len, uint8_t id) { struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id]; - struct ao_lpc_ssp_state *state = &ao_lpc_ssp_state[id]; - - state->tx_count = state->rx_count = len; - state->tx = &ao_spi_tx_dummy; - state->tx_inc = 0; - state->rx = block; - state->rx_inc = 1; - ao_spi_run(lpc_ssp, state); + uint8_t *i = block; + + spi_loop(len, 0xff, *i++ =); } void ao_spi_duplex(const void *out, void *in, uint16_t len, uint8_t id) { struct lpc_ssp *lpc_ssp = ao_lpc_ssp[id]; - struct ao_lpc_ssp_state *state = &ao_lpc_ssp_state[id]; - - state->tx_count = state->rx_count = len; - state->tx = out; - state->tx_inc = 1; - state->rx = in; - state->rx_inc = 1; - ao_spi_run(lpc_ssp, state); + const uint8_t *o = out; + uint8_t *i = in; + + spi_loop(len, *o++, *i++ =); } void @@ -223,10 +149,6 @@ ao_spi_init(void) lpc_scb.presetctrl &= ~(1 << LPC_SCB_PRESETCTRL_SSP0_RST_N); lpc_scb.presetctrl |= (1 << LPC_SCB_PRESETCTRL_SSP0_RST_N); ao_spi_channel_init(0); - - /* Configure NVIC */ - lpc_nvic_set_enable(LPC_ISR_SSP0_POS); - lpc_nvic_set_priority(LPC_ISR_SSP0_POS, 0); #endif #if HAS_SPI_1 @@ -277,10 +199,5 @@ ao_spi_init(void) lpc_scb.presetctrl &= ~(1 << LPC_SCB_PRESETCTRL_SSP1_RST_N); lpc_scb.presetctrl |= (1 << LPC_SCB_PRESETCTRL_SSP1_RST_N); ao_spi_channel_init(1); - - /* Configure NVIC */ - lpc_nvic_set_enable(LPC_ISR_SSP1_POS); - lpc_nvic_set_priority(LPC_ISR_SSP1_POS, 0); - #endif /* HAS_SPI_1 */ } |