Add-unidirectional-SPI

Author: hierophect

ports/mimxrt10xx/Makefile

@@ -93,6 +93,9 @@ endif
 
 CFLAGS += $(INC) -Wall -Wno-cast-align -std=gnu11 -nostdlib $(BASE_CFLAGS) $(CFLAGS_MOD) $(COPT)
 
+# Disable some warnings, as do most ports. NXP SDK causes undef, tinyusb causes cast-align
+CFLAGS += -Wno-undef -Wno-cast-align
+
 CFLAGS += \
 	-mthumb \
 	-mapcs \

ports/mimxrt10xx/common-hal/busio/SPI.c

@@ -25,7 +25,6 @@
  * THE SOFTWARE.
  */
 
-//TODO
 #include "shared-bindings/busio/SPI.h"
 #include "py/mperrno.h"
 #include "py/runtime.h"
@@ -35,46 +34,10 @@
 
 #include <stdio.h>
 
-//bool never_reset_sercoms[SERCOM_INST_NUM];
-//
-//void never_reset_sercom(Sercom* sercom) {
-//    // Reset all SERCOMs except the ones being used by on-board devices.
-//    Sercom *sercom_instances[SERCOM_INST_NUM] = SERCOM_INSTS;
-//    for (int i = 0; i < SERCOM_INST_NUM; i++) {
-//        if (sercom_instances[i] == sercom) {
-//            never_reset_sercoms[i] = true;
-//            break;
-//        }
-//    }
-//}
-//
-//void allow_reset_sercom(Sercom* sercom) {
-//    // Reset all SERCOMs except the ones being used by on-board devices.
-//    Sercom *sercom_instances[SERCOM_INST_NUM] = SERCOM_INSTS;
-//    for (int i = 0; i < SERCOM_INST_NUM; i++) {
-//        if (sercom_instances[i] == sercom) {
-//            never_reset_sercoms[i] = false;
-//            break;
-//        }
-//    }
-//}
-//
-//void reset_sercoms(void) {
-//    // Reset all SERCOMs except the ones being used by on-board devices.
-//    Sercom *sercom_instances[SERCOM_INST_NUM] = SERCOM_INSTS;
-//    for (int i = 0; i < SERCOM_INST_NUM; i++) {
-//        if (never_reset_sercoms[i]) {
-//            continue;
-//        }
-//    #ifdef MICROPY_HW_APA102_SERCOM
-//        if (sercom_instances[i] == MICROPY_HW_APA102_SERCOM) {
-//            continue;
-//        }
-//    #endif
-//        // SWRST is same for all modes of SERCOMs.
-//        sercom_instances[i]->SPI.CTRLA.bit.SWRST = 1;
-//    }
-//}
+//arrays use 0 based numbering: SPI1 is stored at index 0
+#define MAX_SPI 4
+STATIC bool reserved_spi[MAX_SPI];
+STATIC bool never_reset_spi[MAX_SPI];
 
 static void config_periph_pin(const mcu_periph_obj_t *periph) {
     IOMUXC_SetPinMux(
@@ -97,115 +60,180 @@ static void config_periph_pin(const mcu_periph_obj_t *periph) {
 
 #define LPSPI_MASTER_CLK_FREQ (CLOCK_GetFreq(kCLOCK_Usb1PllPfd0Clk) / (CLOCK_GetDiv(kCLOCK_LpspiDiv)))
 
+void spi_reset(void) {
+    for (int i = 0; i < MAX_SPI; i++) {
+        reserved_spi[i] = false;
+    }
+}
+
 void common_hal_busio_spi_construct(busio_spi_obj_t *self,
         const mcu_pin_obj_t *clock, const mcu_pin_obj_t *mosi,
         const mcu_pin_obj_t *miso) {
 
-    // TODO: Allow none mosi or miso
+    const uint32_t sck_count = MP_ARRAY_SIZE(mcu_spi_sck_list);
+    const uint32_t miso_count = MP_ARRAY_SIZE(mcu_spi_miso_list);
+    const uint32_t mosi_count = MP_ARRAY_SIZE(mcu_spi_mosi_list);
+    bool spi_taken = false;
 
-    const uint32_t sck_count = sizeof(mcu_spi_sck_list) / sizeof(mcu_periph_obj_t);
-    const uint32_t miso_count = sizeof(mcu_spi_miso_list) / sizeof(mcu_periph_obj_t);
-    const uint32_t mosi_count = sizeof(mcu_spi_mosi_list) / sizeof(mcu_periph_obj_t);
-
-    for (uint32_t i = 0; i < sck_count; ++i) {
-        if (mcu_spi_sck_list[i].pin != clock)
+    for (uint i = 0; i < sck_count; i++) {
+        if (mcu_spi_sck_list[i].pin != clock) {
             continue;
-
-        for (uint32_t j = 0; j < miso_count; ++j) {
-            if (mcu_spi_miso_list[j].pin != miso)
-                continue;
-
-            if (mcu_spi_miso_list[j].bank_idx != mcu_spi_sck_list[i].bank_idx)
-                continue;
-
-            for (uint32_t k = 0; k < mosi_count; ++k) {
-                if (mcu_spi_mosi_list[k].pin != mosi)
+        }
+        //if both MOSI and MISO exist, loop search normally
+        if ((mosi != NULL) && (miso != NULL)) {
+            for (uint j = 0; j < mosi_count; j++) {
+                if ((mcu_spi_mosi_list[i].pin != mosi) 
+                    || (mcu_spi_sck_list[i].bank_idx != mcu_spi_mosi_list[j].bank_idx)){
                     continue;
-
-                if (mcu_spi_mosi_list[k].bank_idx != mcu_spi_miso_list[j].bank_idx)
+                }
+                for (uint k = 0; k < miso_count; k++) {
+                    if ((mcu_spi_miso_list[k].pin != miso) //everything needs the same index
+                        || (mcu_spi_sck_list[i].bank_idx != mcu_spi_miso_list[k].bank_idx)) {
+                        continue;
+                    }
+                    //keep looking if the SPI is taken, edge case
+                    if (reserved_spi[mcu_spi_sck_list[i].bank_idx - 1]) {
+                        spi_taken = true;
+                        continue;
+                    }
+                    //store pins if not
+                    self->clock = &mcu_spi_sck_list[i];
+                    self->mosi = &mcu_spi_mosi_list[j];
+                    self->miso = &mcu_spi_miso_list[k];
+                    break;
+                }
+                if (self->clock != NULL) {
+                    break; // Multi-level break to pick lowest peripheral
+                }
+            }
+            if (self->clock != NULL) {
+                break;
+            }
+        // if just MISO, reduce search
+        } else if (miso != NULL) {
+            for (uint j = 0; j < miso_count; j++) {
+                if ((mcu_spi_miso_list[j].pin != miso) //only SCK and MISO need the same index
+                    || (mcu_spi_sck_list[i].bank_idx != mcu_spi_miso_list[j].bank_idx)) {
                     continue;
-
-                self->clock_pin = &mcu_spi_sck_list[i];
-                self->miso_pin = &mcu_spi_miso_list[j];
-                self->mosi_pin = &mcu_spi_mosi_list[k];
-
+                }
+                if (reserved_spi[mcu_spi_sck_list[i].bank_idx - 1]) {
+                    spi_taken = true;
+                    continue;
+                }
+                self->clock = &mcu_spi_sck_list[i];
+                self->mosi = NULL;
+                self->miso = &mcu_spi_miso_list[j];
+                break;
+            }
+            if (self->clock != NULL) {
+                break;
+            }
+        // if just MOSI, reduce search
+        } else if (mosi != NULL) {
+            for (uint j = 0; j < mosi_count; j++) {
+                if ((mcu_spi_mosi_list[j].pin != mosi) //only SCK and MOSI need the same index
+                    || (mcu_spi_sck_list[i].bank_idx != mcu_spi_mosi_list[j].bank_idx)) {
+                    continue;
+                }
+                if (reserved_spi[mcu_spi_sck_list[i].bank_idx - 1]) {
+                    spi_taken = true;
+                    continue;
+                }
+                self->clock = &mcu_spi_sck_list[i];
+                self->mosi = &mcu_spi_mosi_list[j];
+                self->miso = NULL;
                 break;
             }
+            if (self->clock != NULL) {
+                break;
+            }
+        } else {
+            //throw an error immediately
+            mp_raise_ValueError(translate("Must provide MISO or MOSI pin"));
         }
     }
 
-    if(self->clock_pin == NULL || self->mosi_pin == NULL || self->miso_pin == NULL) {
-        mp_raise_RuntimeError(translate("Invalid SPI pin selection"));
+    // for (uint32_t i = 0; i < sck_count; ++i) {
+    //     if (mcu_spi_sck_list[i].pin != clock)
+    //         continue;
+
+    //     for (uint32_t j = 0; j < miso_count; ++j) {
+    //         if (mcu_spi_miso_list[j].pin != miso)
+    //             continue;
+
+    //         if (mcu_spi_miso_list[j].bank_idx != mcu_spi_sck_list[i].bank_idx)
+    //             continue;
+
+    //         for (uint32_t k = 0; k < mosi_count; ++k) {
+    //             if (mcu_spi_mosi_list[k].pin != mosi)
+    //                 continue;
+
+    //             if (mcu_spi_mosi_list[k].bank_idx != mcu_spi_miso_list[j].bank_idx)
+    //                 continue;
+
+    //             self->clock = &mcu_spi_sck_list[i];
+    //             self->miso_pin = &mcu_spi_miso_list[j];
+    //             self->mosi_pin = &mcu_spi_mosi_list[k];
+
+    //             break;
+    //         }
+    //     }
+    // }
+
+    if (self->clock != NULL && (self->mosi != NULL || self->miso != NULL)) {
+        self->spi = mcu_spi_banks[self->clock->bank_idx - 1];
     } else {
-        self->spi = mcu_spi_banks[self->clock_pin->bank_idx - 1];
+        if (spi_taken) {
+            mp_raise_ValueError(translate("Hardware busy, try alternative pins"));
+        } else {
+            mp_raise_ValueError(translate("Invalid SPI pin selection"));
+        }
     }
 
-    config_periph_pin(self->mosi_pin);
-    config_periph_pin(self->miso_pin);
-    config_periph_pin(self->clock_pin);
+    config_periph_pin(self->clock);
+    if (self->mosi != NULL) {
+        config_periph_pin(self->mosi);
+    }
+    if (self->miso != NULL) {
+        config_periph_pin(self->miso);
+    }
+    reserved_spi[self->clock->bank_idx - 1] = true;
 
     lpspi_master_config_t config = { 0 };
     LPSPI_MasterGetDefaultConfig(&config);
 
     // Always start at 250khz which is what SD cards need. They are sensitive to
     // SPI bus noise before they are put into SPI mode.
     config.baudRate = 250000;
-
     LPSPI_MasterInit(self->spi, &config, LPSPI_MASTER_CLK_FREQ);
-
     LPSPI_Enable(self->spi, false);
     uint32_t tcrPrescaleValue;
     self->baudrate = LPSPI_MasterSetBaudRate(self->spi, config.baudRate, LPSPI_MASTER_CLK_FREQ, &tcrPrescaleValue);
     LPSPI_Enable(self->spi, true);
 
-    claim_pin(self->clock_pin->pin);
-
-//    if (mosi_none) {
-//        self->MOSI_pin = NO_PIN;
-//    } else {
-//        gpio_set_pin_direction(mosi->number, GPIO_DIRECTION_OUT);
-//        gpio_set_pin_pull_mode(mosi->number, GPIO_PULL_OFF);
-//        gpio_set_pin_function(mosi->number, mosi_pinmux);
-//        self->MOSI_pin = mosi->number;
-        claim_pin(self->mosi_pin->pin);
-//    }
-
-//    if (miso_none) {
-//        self->MISO_pin = NO_PIN;
-//    } else {
-//        gpio_set_pin_direction(miso->number, GPIO_DIRECTION_IN);
-//        gpio_set_pin_pull_mode(miso->number, GPIO_PULL_OFF);
-//        gpio_set_pin_function(miso->number, miso_pinmux);
-//        self->MISO_pin = miso->number;
-        claim_pin(self->miso_pin->pin);
-//    }
+    claim_pin(self->clock->pin);
+    if (self->mosi != NULL) {
+        claim_pin(self->mosi->pin);
+    }
+    if (self->miso != NULL) {
+        claim_pin(self->miso->pin);
+    }
 }
 
 void common_hal_busio_spi_never_reset(busio_spi_obj_t *self) {
-//    never_reset_sercom(self->spi_desc.dev.prvt);
-
-//    never_reset_pin_number(self->clock_pin);
-//    never_reset_pin_number(self->MOSI_pin);
-//    never_reset_pin_number(self->MISO_pin);
+    // TODO
 }
 
 bool common_hal_busio_spi_deinited(busio_spi_obj_t *self) {
-    return self->clock_pin == NULL;
+    return self->clock == NULL;
 }
 
 void common_hal_busio_spi_deinit(busio_spi_obj_t *self) {
     if (common_hal_busio_spi_deinited(self)) {
         return;
     }
 
-//    allow_reset_sercom(self->spi_desc.dev.prvt);
-
-//    spi_m_sync_disable(&self->spi_desc);
-//    spi_m_sync_deinit(&self->spi_desc);
-//    reset_pin_number(self->clock_pin);
-//    reset_pin_number(self->MOSI_pin);
-//    reset_pin_number(self->MISO_pin);
-    self->clock_pin = NULL;
+    self->clock = NULL;
 }
 
 bool common_hal_busio_spi_configure(busio_spi_obj_t *self,
@@ -260,6 +288,9 @@ bool common_hal_busio_spi_write(busio_spi_obj_t *self,
     if (len == 0) {
         return true;
     }
+    if (self->mosi == NULL) {
+        mp_raise_ValueError(translate("No MOSI Pin"));
+    }
 
     lpspi_transfer_t xfer = { 0 };
     xfer.txData = (uint8_t*)data;
@@ -278,6 +309,9 @@ bool common_hal_busio_spi_read(busio_spi_obj_t *self,
     if (len == 0) {
         return true;
     }
+    if (self->miso == NULL) {
+        mp_raise_ValueError(translate("No MISO Pin"));
+    }
 
     LPSPI_SetDummyData(self->spi, write_value);
 
@@ -296,6 +330,9 @@ bool common_hal_busio_spi_transfer(busio_spi_obj_t *self, uint8_t *data_out, uin
     if (len == 0) {
         return true;
     }
+    if (self->miso == NULL || self->mosi == NULL) {
+        mp_raise_ValueError(translate("Missing MISO or MOSI Pin"));
+    }
 
     LPSPI_SetDummyData(self->spi, 0xFF);
 

ports/mimxrt10xx/common-hal/busio/SPI.h

@@ -38,9 +38,11 @@ typedef struct {
     LPSPI_Type *spi;
     bool has_lock;
     uint32_t baudrate;
-    const mcu_periph_obj_t *clock_pin;
-    const mcu_periph_obj_t *mosi_pin;
-    const mcu_periph_obj_t *miso_pin;
+    const mcu_periph_obj_t *clock;
+    const mcu_periph_obj_t *mosi;
+    const mcu_periph_obj_t *miso;
 } busio_spi_obj_t;
 
+void spi_reset(void);
+
 #endif // MICROPY_INCLUDED_MIMXRT10XX_COMMON_HAL_BUSIO_SPI_H

ports/mimxrt10xx/supervisor/port.c

@@ -41,6 +41,7 @@
 #include "common-hal/pulseio/PulseOut.h"
 #include "common-hal/pulseio/PWMOut.h"
 #include "common-hal/rtc/RTC.h"
+#include "common-hal/busio/SPI.h"
 
 #include "reset.h"
 #include "tick.h"
@@ -264,7 +265,7 @@ safe_mode_t port_init(void) {
 }
 
 void reset_port(void) {
-    //reset_sercoms();
+    spi_reset();
 
 #if CIRCUITPY_AUDIOIO
     audio_dma_reset();