*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; version 2 of the License.
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
*/
#include <ao.h>
+#include <ao_exti.h>
void
ao_debug_out(char c)
stm_usart1.dr = c;
}
-static void
+static int
_ao_usart_tx_start(struct ao_stm_usart *usart)
{
- if (!ao_fifo_empty(usart->tx_fifo) && !usart->tx_started)
- {
- usart->tx_started = 1;
- ao_fifo_remove(usart->tx_fifo, usart->reg->dr);
+ if (!ao_fifo_empty(usart->tx_fifo)) {
+#if HAS_SERIAL_SW_FLOW
+ if (usart->gpio_cts && ao_gpio_get(usart->gpio_cts, usart->pin_cts) == 1) {
+ ao_exti_enable(usart->gpio_cts, usart->pin_cts);
+ return 0;
+ }
+#endif
+ if (usart->reg->sr & (1 << STM_USART_SR_TXE))
+ {
+ usart->tx_running = 1;
+ usart->reg->cr1 |= (1 << STM_USART_CR1_TXEIE) | (1 << STM_USART_CR1_TCIE);
+ ao_fifo_remove(usart->tx_fifo, usart->reg->dr);
+ ao_wakeup(&usart->tx_fifo);
+ return 1;
+ }
}
+ return 0;
}
+#if HAS_SERIAL_SW_FLOW
static void
-ao_usart_isr(struct ao_stm_usart *usart, int stdin)
+_ao_usart_cts(struct ao_stm_usart *usart)
{
- uint32_t sr;
-
- sr = usart->reg->sr;
- usart->reg->sr = 0;
+ if (_ao_usart_tx_start(usart))
+ ao_exti_disable(usart->gpio_cts, usart->pin_cts);
+}
+#endif
- if (sr & (1 << STM_USART_SR_RXNE)) {
- char c = usart->reg->dr;
- if (!ao_fifo_full(usart->rx_fifo))
- ao_fifo_insert(usart->rx_fifo, c);
- ao_wakeup(&usart->rx_fifo);
- if (stdin)
- ao_wakeup(&ao_stdin_ready);
+static void
+_ao_usart_rx(struct ao_stm_usart *usart, int is_stdin)
+{
+ if (usart->reg->sr & (1 << STM_USART_SR_RXNE)) {
+ if (!ao_fifo_full(usart->rx_fifo)) {
+ ao_fifo_insert(usart->rx_fifo, usart->reg->dr);
+ ao_wakeup(&usart->rx_fifo);
+ if (is_stdin)
+ ao_wakeup(&ao_stdin_ready);
+#if HAS_SERIAL_SW_FLOW
+ /* If the fifo is nearly full, turn off RTS and wait
+ * for it to drain a bunch
+ */
+ if (usart->gpio_rts && ao_fifo_mostly(usart->rx_fifo)) {
+ ao_gpio_set(usart->gpio_rts, usart->pin_rts, 1);
+ usart->rts = 0;
+ }
+#endif
+ } else {
+ usart->reg->cr1 &= ~(1 << STM_USART_CR1_RXNEIE);
+ }
}
- if (sr & (1 << STM_USART_SR_TC)) {
- usart->tx_started = 0;
- _ao_usart_tx_start(usart);
- ao_wakeup(&usart->tx_fifo);
+}
+
+static void
+ao_usart_isr(struct ao_stm_usart *usart, int is_stdin)
+{
+ _ao_usart_rx(usart, is_stdin);
+
+ if (!_ao_usart_tx_start(usart))
+ usart->reg->cr1 &= ~(1<< STM_USART_CR1_TXEIE);
+
+ if (usart->reg->sr & (1 << STM_USART_SR_TC)) {
+ usart->tx_running = 0;
+ usart->reg->cr1 &= ~(1 << STM_USART_CR1_TCIE);
+ if (usart->draining) {
+ usart->draining = 0;
+ ao_wakeup(&usart->tx_fifo);
+ }
}
}
-int
+static int
_ao_usart_pollchar(struct ao_stm_usart *usart)
{
int c;
else {
uint8_t u;
ao_fifo_remove(usart->rx_fifo,u);
+ if ((usart->reg->cr1 & (1 << STM_USART_CR1_RXNEIE)) == 0) {
+ if (ao_fifo_barely(usart->rx_fifo))
+ usart->reg->cr1 |= (1 << STM_USART_CR1_RXNEIE);
+ }
+#if HAS_SERIAL_SW_FLOW
+ /* If we've cleared RTS, check if there's space now and turn it back on */
+ if (usart->gpio_rts && usart->rts == 0 && ao_fifo_barely(usart->rx_fifo)) {
+ ao_gpio_set(usart->gpio_rts, usart->pin_rts, 0);
+ usart->rts = 1;
+ }
+#endif
c = u;
}
return c;
}
-char
+static char
ao_usart_getchar(struct ao_stm_usart *usart)
{
int c;
return ao_sleep_for(&usart->rx_fifo, timeout);
}
-void
+static void
ao_usart_putchar(struct ao_stm_usart *usart, char c)
{
ao_arch_block_interrupts();
ao_arch_release_interrupts();
}
-void
+static void
ao_usart_drain(struct ao_stm_usart *usart)
{
ao_arch_block_interrupts();
- while (!ao_fifo_empty(usart->tx_fifo))
+ while (!ao_fifo_empty(usart->tx_fifo) || usart->tx_running) {
+ usart->draining = 1;
ao_sleep(&usart->tx_fifo);
+ }
ao_arch_release_interrupts();
}
},
};
-void
+static void
ao_usart_set_speed(struct ao_stm_usart *usart, uint8_t speed)
{
if (speed > AO_SERIAL_SPEED_115200)
usart->reg->brr = ao_usart_speeds[speed].brr;
}
-void
-ao_usart_init(struct ao_stm_usart *usart)
+static void
+ao_usart_init(struct ao_stm_usart *usart, int hw_flow)
{
usart->reg->cr1 = ((0 << STM_USART_CR1_OVER8) |
(1 << STM_USART_CR1_UE) |
(0 << STM_USART_CR1_PS) |
(0 << STM_USART_CR1_PEIE) |
(0 << STM_USART_CR1_TXEIE) |
- (1 << STM_USART_CR1_TCIE) |
+ (0 << STM_USART_CR1_TCIE) |
(1 << STM_USART_CR1_RXNEIE) |
(0 << STM_USART_CR1_IDLEIE) |
(1 << STM_USART_CR1_TE) |
(0 << STM_USART_CR3_IREN) |
(0 << STM_USART_CR3_EIE));
+ if (hw_flow)
+ usart->reg->cr3 |= ((1 << STM_USART_CR3_CTSE) |
+ (1 << STM_USART_CR3_RTSE));
+
/* Pick a 9600 baud rate */
ao_usart_set_speed(usart, AO_SERIAL_SPEED_9600);
}
-void
+#if HAS_SERIAL_HW_FLOW
+static void
ao_usart_set_flow(struct ao_stm_usart *usart)
{
- usart->reg->cr3 |= ((1 << STM_USART_CR3_CTSE) |
- (1 << STM_USART_CR3_RTSE));
}
+#endif
#if HAS_SERIAL_1
void
ao_serial1_set_speed(uint8_t speed)
{
+ ao_usart_drain(&ao_stm_usart1);
ao_usart_set_speed(&ao_stm_usart1, speed);
}
#endif /* HAS_SERIAL_1 */
void
ao_serial2_set_speed(uint8_t speed)
{
+ ao_usart_drain(&ao_stm_usart2);
ao_usart_set_speed(&ao_stm_usart2, speed);
}
+
+#if HAS_SERIAL_SW_FLOW
+static void
+ao_serial2_cts(void)
+{
+ _ao_usart_cts(&ao_stm_usart2);
+}
+#endif
+
#endif /* HAS_SERIAL_2 */
#if HAS_SERIAL_3
struct ao_stm_usart ao_stm_usart3;
-void stm_usart3_isr(void) { ao_usart_isr(&ao_stm_usart3, USE_SERIAL_2_STDIN); }
+void stm_usart3_isr(void) { ao_usart_isr(&ao_stm_usart3, USE_SERIAL_3_STDIN); }
char
ao_serial3_getchar(void)
void
ao_serial3_set_speed(uint8_t speed)
{
+ ao_usart_drain(&ao_stm_usart3);
ao_usart_set_speed(&ao_stm_usart3, speed);
}
+
+void
+ao_serial3_drain(void)
+{
+ ao_usart_drain(&ao_stm_usart3);
+}
#endif /* HAS_SERIAL_3 */
+#if HAS_SERIAL_SW_FLOW
+static void
+ao_serial_set_sw_rts_cts(struct ao_stm_usart *usart,
+ void (*isr)(void),
+ struct stm_gpio *port_rts,
+ int pin_rts,
+ struct stm_gpio *port_cts,
+ int pin_cts)
+{
+ /* Pull RTS low to note that there's space in the FIFO
+ */
+ ao_enable_output(port_rts, pin_rts, 0);
+ usart->gpio_rts = port_rts;
+ usart->pin_rts = pin_rts;
+ usart->rts = 1;
+
+ ao_exti_setup(port_cts, pin_cts, AO_EXTI_MODE_FALLING|AO_EXTI_PRIORITY_MED, isr);
+ usart->gpio_cts = port_cts;
+ usart->pin_cts = pin_cts;
+}
+#endif
+
void
ao_serial_init(void)
{
stm_rcc.apb2enr |= (1 << STM_RCC_APB2ENR_USART1EN);
ao_stm_usart1.reg = &stm_usart1;
- ao_usart_init(&ao_stm_usart1);
+ ao_usart_init(&ao_stm_usart1, 0);
stm_nvic_set_enable(STM_ISR_USART1_POS);
- stm_nvic_set_priority(STM_ISR_USART1_POS, 4);
+ stm_nvic_set_priority(STM_ISR_USART1_POS, AO_STM_NVIC_MED_PRIORITY);
#if USE_SERIAL_1_STDIN && !DELAY_SERIAL_1_STDIN
ao_add_stdio(_ao_serial1_pollchar,
ao_serial1_putchar,
stm_afr_set(&stm_gpioa, 2, STM_AFR_AF7);
stm_afr_set(&stm_gpioa, 3, STM_AFR_AF7);
-#if USE_SERIAL_2_FLOW
+# if USE_SERIAL_2_FLOW
+# if USE_SERIAL_2_SW_FLOW
+ ao_serial_set_sw_rts_cts(&ao_stm_usart2,
+ ao_serial2_cts,
+ SERIAL_2_PORT_RTS,
+ SERIAL_2_PIN_RTS,
+ SERIAL_2_PORT_CTS,
+ SERIAL_2_PIN_CTS);
+# else
stm_afr_set(&stm_gpioa, 0, STM_AFR_AF7);
stm_afr_set(&stm_gpioa, 1, STM_AFR_AF7);
-#endif
+# endif
+# endif
#else
#if SERIAL_2_PD5_PD6
stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIODEN);
stm_rcc.apb1enr |= (1 << STM_RCC_APB1ENR_USART2EN);
ao_stm_usart2.reg = &stm_usart2;
- ao_usart_init(&ao_stm_usart2);
-#if USE_SERIAL_2_FLOW
- ao_usart_set_flow(&ao_stm_usart2);
-#endif
+ ao_usart_init(&ao_stm_usart2, USE_SERIAL_2_FLOW && !USE_SERIAL_2_SW_FLOW);
stm_nvic_set_enable(STM_ISR_USART2_POS);
- stm_nvic_set_priority(STM_ISR_USART2_POS, 4);
+ stm_nvic_set_priority(STM_ISR_USART2_POS, AO_STM_NVIC_MED_PRIORITY);
#if USE_SERIAL_2_STDIN && !DELAY_SERIAL_2_STDIN
ao_add_stdio(_ao_serial2_pollchar,
ao_serial2_putchar,
stm_rcc.apb1enr |= (1 << STM_RCC_APB1ENR_USART3EN);
ao_stm_usart3.reg = &stm_usart3;
- ao_usart_init(&ao_stm_usart3);
+ ao_usart_init(&ao_stm_usart3, 0);
stm_nvic_set_enable(STM_ISR_USART3_POS);
- stm_nvic_set_priority(STM_ISR_USART3_POS, 4);
+ stm_nvic_set_priority(STM_ISR_USART3_POS, AO_STM_NVIC_MED_PRIORITY);
#if USE_SERIAL_3_STDIN && !DELAY_SERIAL_3_STDIN
ao_add_stdio(_ao_serial3_pollchar,
ao_serial3_putchar,
projects / fw / altos / blobdiff