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Allow MOSI/MISO exclusion
1 parent 5b127bd commit 6ab75fe

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1 file changed

+95
-48
lines changed
  • ports/stm32f4/common-hal/busio

1 file changed

+95
-48
lines changed

ports/stm32f4/common-hal/busio/SPI.c

Lines changed: 95 additions & 48 deletions
Original file line numberDiff line numberDiff line change
@@ -36,6 +36,9 @@
3636
#include "supervisor/shared/translate.h"
3737
#include "common-hal/microcontroller/Pin.h"
3838

39+
// Note that any bugs introduced in this file can cause crashes at startup
40+
// for chips using external SPI flash.
41+
3942
#define MAX_SPI 6 //TODO; replace this as part of periph cleanup
4043
#define ALL_CLOCKS 0xFF
4144

@@ -79,38 +82,80 @@ void common_hal_busio_spi_construct(busio_spi_obj_t *self,
7982
uint8_t sck_len = sizeof(mcu_spi_sck_list)/sizeof(*mcu_spi_sck_list);
8083
uint8_t mosi_len = sizeof(mcu_spi_mosi_list)/sizeof(*mcu_spi_mosi_list);
8184
uint8_t miso_len = sizeof(mcu_spi_miso_list)/sizeof(*mcu_spi_miso_list);
82-
8385
bool spi_taken = false;
84-
//sck
86+
87+
//sck is not optional. MOSI and MISO are
8588
for(uint i=0; i<sck_len;i++) {
8689
if (mcu_spi_sck_list[i].pin == sck) {
87-
//mosi
88-
for(uint j=0; j<mosi_len;j++) {
89-
if (mcu_spi_mosi_list[j].pin == mosi) {
90-
//miso
91-
for(uint k=0; k<miso_len;k++) {
92-
if ((mcu_spi_miso_list[k].pin == miso) //everything needs the same index
93-
&& (mcu_spi_sck_list[i].spi_index == mcu_spi_mosi_list[j].spi_index)
94-
&& (mcu_spi_sck_list[i].spi_index == mcu_spi_miso_list[k].spi_index)) {
95-
//keep looking if the SPI is taken, edge case
96-
if(reserved_spi[mcu_spi_sck_list[i].spi_index-1]) {
97-
spi_taken = true;
98-
continue;
90+
//if both mosi and miso exist, loop search normally
91+
if ((mosi != mp_const_none) && (miso != mp_const_none)) {
92+
//mosi
93+
for(uint j=0; j<mosi_len;j++) {
94+
if (mcu_spi_mosi_list[j].pin == mosi) {
95+
//miso
96+
for(uint k=0; k<miso_len;k++) {
97+
if ((mcu_spi_miso_list[k].pin == miso) //everything needs the same index
98+
&& (mcu_spi_sck_list[i].spi_index == mcu_spi_mosi_list[j].spi_index)
99+
&& (mcu_spi_sck_list[i].spi_index == mcu_spi_miso_list[k].spi_index)) {
100+
//keep looking if the SPI is taken, edge case
101+
if(reserved_spi[mcu_spi_sck_list[i].spi_index-1]) {
102+
spi_taken = true;
103+
continue;
104+
}
105+
//store pins if not
106+
self->sck = &mcu_spi_sck_list[i];
107+
self->mosi = &mcu_spi_mosi_list[j];
108+
self->miso = &mcu_spi_miso_list[k];
109+
break;
99110
}
100-
//store pins if not
101-
self->sck = &mcu_spi_sck_list[i];
102-
self->mosi = &mcu_spi_mosi_list[j];
103-
self->miso = &mcu_spi_miso_list[k];
104-
break;
105-
}
106-
}
111+
}
112+
}
107113
}
114+
// if just miso, reduce search
115+
} else if (miso != mp_const_none) {
116+
for(uint j=0; j<miso_len;j++) {
117+
if ((mcu_spi_miso_list[j].pin == miso) //only sck and miso need the same index
118+
&& (mcu_spi_sck_list[i].spi_index == mcu_spi_miso_list[j].spi_index)) {
119+
//keep looking if the SPI is taken, edge case
120+
if(reserved_spi[mcu_spi_sck_list[i].spi_index-1]) {
121+
spi_taken = true;
122+
continue;
123+
}
124+
//store pins if not
125+
self->sck = &mcu_spi_sck_list[i];
126+
self->mosi = NULL;
127+
self->miso = &mcu_spi_miso_list[j];
128+
break;
129+
}
130+
}
131+
// if just mosi, reduce search
132+
} else if (mosi != mp_const_none) {
133+
for(uint j=0; j<mosi_len;j++) {
134+
if ((mcu_spi_mosi_list[j].pin == mosi) //only sck and mosi need the same index
135+
&& (mcu_spi_sck_list[i].spi_index == mcu_spi_mosi_list[j].spi_index)) {
136+
//keep looking if the SPI is taken, edge case
137+
if(reserved_spi[mcu_spi_sck_list[i].spi_index-1]) {
138+
spi_taken = true;
139+
continue;
140+
}
141+
//store pins if not
142+
self->sck = &mcu_spi_sck_list[i];
143+
self->mosi = &mcu_spi_mosi_list[j];
144+
self->miso = NULL;
145+
break;
146+
}
147+
}
148+
} else {
149+
//throw an error immediately
150+
mp_raise_ValueError(translate("Must provide MISO or MOSI pin"));
108151
}
109152
}
110153
}
111154

112155
//handle typedef selection, errors
113-
if(self->sck!=NULL && self->mosi!=NULL && self->miso!=NULL ) {
156+
if( (self->sck!=NULL && self->mosi!=NULL && self->miso != NULL) ||
157+
(self->sck!=NULL && self->mosi!=NULL && miso == mp_const_none) ||
158+
(self->sck!=NULL && self->miso!=NULL && mosi == mp_const_none)) {
114159
SPIx = mcu_spi_banks[self->sck->spi_index-1];
115160
} else {
116161
if (spi_taken) {
@@ -129,26 +174,31 @@ void common_hal_busio_spi_construct(busio_spi_obj_t *self,
129174
GPIO_InitStruct.Alternate = self->sck->altfn_index;
130175
HAL_GPIO_Init(pin_port(sck->port), &GPIO_InitStruct);
131176

132-
GPIO_InitStruct.Pin = pin_mask(mosi->number);
133-
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
134-
GPIO_InitStruct.Pull = GPIO_NOPULL;
135-
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
136-
GPIO_InitStruct.Alternate = self->mosi->altfn_index;
137-
HAL_GPIO_Init(pin_port(mosi->port), &GPIO_InitStruct);
177+
if (self->mosi != NULL) {
178+
GPIO_InitStruct.Pin = pin_mask(mosi->number);
179+
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
180+
GPIO_InitStruct.Pull = GPIO_NOPULL;
181+
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
182+
GPIO_InitStruct.Alternate = self->mosi->altfn_index;
183+
HAL_GPIO_Init(pin_port(mosi->port), &GPIO_InitStruct);
184+
}
138185

139-
GPIO_InitStruct.Pin = pin_mask(miso->number);
140-
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
141-
GPIO_InitStruct.Pull = GPIO_NOPULL;
142-
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
143-
GPIO_InitStruct.Alternate = self->miso->altfn_index;
144-
HAL_GPIO_Init(pin_port(miso->port), &GPIO_InitStruct);
186+
if (self->miso != NULL) {
187+
GPIO_InitStruct.Pin = pin_mask(miso->number);
188+
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
189+
GPIO_InitStruct.Pull = GPIO_NOPULL;
190+
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
191+
GPIO_InitStruct.Alternate = self->miso->altfn_index;
192+
HAL_GPIO_Init(pin_port(miso->port), &GPIO_InitStruct);
193+
}
145194

146195
spi_clock_enable(1<<(self->sck->spi_index - 1));
147196
reserved_spi[self->sck->spi_index - 1] = true;
148197

149198
self->handle.Instance = SPIx;
150199
self->handle.Init.Mode = SPI_MODE_MASTER;
151-
self->handle.Init.Direction = SPI_DIRECTION_2LINES;
200+
// Direction change only required for RX only, see RefMan RM0090:884
201+
self->handle.Init.Direction = (self->mosi == NULL) ? SPI_CR1_RXONLY : SPI_DIRECTION_2LINES;
152202
self->handle.Init.DataSize = SPI_DATASIZE_8BIT;
153203
self->handle.Init.CLKPolarity = SPI_POLARITY_LOW;
154204
self->handle.Init.CLKPhase = SPI_PHASE_1EDGE;
@@ -169,17 +219,17 @@ void common_hal_busio_spi_construct(busio_spi_obj_t *self,
169219
self->bits = 8;
170220

171221
claim_pin(sck);
172-
claim_pin(mosi);
173-
claim_pin(miso);
222+
if (self->mosi != NULL) claim_pin(mosi);
223+
if (self->miso != NULL) claim_pin(miso);
174224
}
175225

176226
void common_hal_busio_spi_never_reset(busio_spi_obj_t *self) {
177227
for(size_t i = 0 ; i < MP_ARRAY_SIZE(mcu_spi_banks); i++) {
178228
if (mcu_spi_banks[i] == self->handle.Instance) {
179229
never_reset_spi[i] = true;
180230
never_reset_pin_number(self->sck->pin->port, self->sck->pin->number);
181-
never_reset_pin_number(self->mosi->pin->port, self->mosi->pin->number);
182-
never_reset_pin_number(self->miso->pin->port, self->miso->pin->number);
231+
if (self->mosi != NULL) never_reset_pin_number(self->mosi->pin->port, self->mosi->pin->number);
232+
if (self->miso != NULL) never_reset_pin_number(self->miso->pin->port, self->miso->pin->number);
183233
break;
184234
}
185235
}
@@ -195,8 +245,8 @@ void common_hal_busio_spi_deinit(busio_spi_obj_t *self) {
195245
never_reset_spi[self->sck->spi_index - 1] = false;
196246

197247
reset_pin_number(self->sck->pin->port,self->sck->pin->number);
198-
reset_pin_number(self->mosi->pin->port,self->mosi->pin->number);
199-
reset_pin_number(self->miso->pin->port,self->miso->pin->number);
248+
if (self->mosi != NULL) reset_pin_number(self->mosi->pin->port,self->mosi->pin->number);
249+
if (self->miso != NULL) reset_pin_number(self->miso->pin->port,self->miso->pin->number);
200250
self->sck = mp_const_none;
201251
self->mosi = mp_const_none;
202252
self->miso = mp_const_none;
@@ -243,13 +293,6 @@ bool common_hal_busio_spi_configure(busio_spi_obj_t *self,
243293

244294
self->handle.Init.BaudRatePrescaler = stm32_baud_to_spi_div(baudrate, &self->prescaler,
245295
get_busclock(self->handle.Instance));
246-
self->handle.Init.Mode = SPI_MODE_MASTER;
247-
self->handle.Init.Direction = SPI_DIRECTION_2LINES;
248-
self->handle.Init.NSS = SPI_NSS_SOFT;
249-
self->handle.Init.FirstBit = SPI_FIRSTBIT_MSB;
250-
self->handle.Init.TIMode = SPI_TIMODE_DISABLE;
251-
self->handle.Init.CRCCalculation = SPI_CRCCALCULATION_DISABLE;
252-
self->handle.Init.CRCPolynomial = 10;
253296

254297
if (HAL_SPI_Init(&self->handle) != HAL_OK)
255298
{
@@ -292,18 +335,22 @@ void common_hal_busio_spi_unlock(busio_spi_obj_t *self) {
292335

293336
bool common_hal_busio_spi_write(busio_spi_obj_t *self,
294337
const uint8_t *data, size_t len) {
338+
if (self->mosi == NULL) mp_raise_ValueError(translate("No MOSI Pin"));
295339
HAL_StatusTypeDef result = HAL_SPI_Transmit (&self->handle, (uint8_t *)data, (uint16_t)len, HAL_MAX_DELAY);
296340
return result == HAL_OK;
297341
}
298342

299343
bool common_hal_busio_spi_read(busio_spi_obj_t *self,
300344
uint8_t *data, size_t len, uint8_t write_value) {
345+
if (self->miso == NULL) mp_raise_ValueError(translate("No MISO Pin"));
301346
HAL_StatusTypeDef result = HAL_SPI_Receive (&self->handle, data, (uint16_t)len, HAL_MAX_DELAY);
302347
return result == HAL_OK;
303348
}
304349

305350
bool common_hal_busio_spi_transfer(busio_spi_obj_t *self,
306351
uint8_t *data_out, uint8_t *data_in, size_t len) {
352+
if (self->miso == NULL) mp_raise_ValueError(translate("No MISO Pin"));
353+
if (self->mosi == NULL) mp_raise_ValueError(translate("No MOSI Pin"));
307354
HAL_StatusTypeDef result = HAL_SPI_TransmitReceive (&self->handle,
308355
data_out, data_in, (uint16_t)len,HAL_MAX_DELAY);
309356
return result == HAL_OK;

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