From 1eb3c66e9136b5934fc306408f00f11a07dea584 Mon Sep 17 00:00:00 2001
From: Damien George <damien.p.george@gmail.com>
Date: Thu, 8 Dec 2016 13:47:01 +1100
Subject: [PATCH] extmod/machine_spi: Provide reusable software SPI class.
So long as a port defines relevant mp_hal_pin_xxx functions (and delay) it
can make use of this software SPI class without the need for additional
code.
---
esp8266/esp_mphal.h | 2 +
extmod/machine_spi.c | 204 ++++++++++++++++++++++++++++++++++++++++++
extmod/machine_spi.h | 7 ++
stmhal/mpconfigport.h | 1 +
stmhal/mphalport.h | 2 +
5 files changed, 216 insertions(+)
diff --git a/esp8266/esp_mphal.h b/esp8266/esp_mphal.h
index 1622667f9..d783f1f09 100644
--- a/esp8266/esp_mphal.h
+++ b/esp8266/esp_mphal.h
@@ -76,8 +76,10 @@ void ets_event_poll(void);
#include "etshal.h"
#include "gpio.h"
#include "esp8266/modmachine.h"
+#define MP_HAL_PIN_FMT "%u"
#define mp_hal_pin_obj_t uint32_t
#define mp_hal_get_pin_obj(o) mp_obj_get_pin(o)
+#define mp_hal_pin_name(p) (p)
void mp_hal_pin_input(mp_hal_pin_obj_t pin);
void mp_hal_pin_output(mp_hal_pin_obj_t pin);
void mp_hal_pin_open_drain(mp_hal_pin_obj_t pin);
diff --git a/extmod/machine_spi.c b/extmod/machine_spi.c
index e3d72ab58..6e7678498 100644
--- a/extmod/machine_spi.c
+++ b/extmod/machine_spi.c
@@ -32,6 +32,12 @@
#if MICROPY_PY_MACHINE_SPI
+// if a port didn't define MSB/LSB constants then provide them
+#ifndef MICROPY_PY_MACHINE_SPI_MSB
+#define MICROPY_PY_MACHINE_SPI_MSB (0)
+#define MICROPY_PY_MACHINE_SPI_LSB (1)
+#endif
+
void mp_machine_soft_spi_transfer(mp_obj_base_t *self_in, size_t len, const uint8_t *src, uint8_t *dest) {
mp_machine_soft_spi_obj_t *self = (mp_machine_soft_spi_obj_t*)self_in;
uint32_t delay_half = self->delay_half;
@@ -93,6 +99,49 @@ void mp_machine_soft_spi_transfer(mp_obj_base_t *self_in, size_t len, const uint
}
}
+/******************************************************************************/
+// MicroPython bindings for generic machine.SPI
+
+STATIC mp_obj_t mp_machine_soft_spi_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args);
+
+mp_obj_t mp_machine_spi_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
+ // check the id argument, if given
+ if (n_args > 0) {
+ if (args[0] != MP_OBJ_NEW_SMALL_INT(-1)) {
+ #if defined(MICROPY_PY_MACHINE_SPI_MAKE_NEW)
+ // dispatch to port-specific constructor
+ extern mp_obj_t MICROPY_PY_MACHINE_SPI_MAKE_NEW(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args);
+ return MICROPY_PY_MACHINE_SPI_MAKE_NEW(type, n_args, n_kw, args);
+ #else
+ mp_raise_ValueError("invalid SPI peripheral");
+ #endif
+ }
+ --n_args;
+ ++args;
+ }
+
+ // software SPI
+ return mp_machine_soft_spi_make_new(type, n_args, n_kw, args);
+}
+
+STATIC mp_obj_t machine_spi_init(size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
+ mp_obj_base_t *s = (mp_obj_base_t*)MP_OBJ_TO_PTR(args[0]);
+ mp_machine_spi_p_t *spi_p = (mp_machine_spi_p_t*)s->type->protocol;
+ spi_p->init(s, n_args - 1, args + 1, kw_args);
+ return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_KW(machine_spi_init_obj, 1, machine_spi_init);
+
+STATIC mp_obj_t machine_spi_deinit(mp_obj_t self) {
+ mp_obj_base_t *s = (mp_obj_base_t*)MP_OBJ_TO_PTR(self);
+ mp_machine_spi_p_t *spi_p = (mp_machine_spi_p_t*)s->type->protocol;
+ if (spi_p->deinit != NULL) {
+ spi_p->deinit(s);
+ }
+ return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_1(machine_spi_deinit_obj, machine_spi_deinit);
+
STATIC void mp_machine_spi_transfer(mp_obj_t self, size_t len, const void *src, void *dest) {
mp_obj_base_t *s = (mp_obj_base_t*)MP_OBJ_TO_PTR(self);
mp_machine_spi_p_t *spi_p = (mp_machine_spi_p_t*)s->type->protocol;
@@ -138,4 +187,159 @@ STATIC mp_obj_t mp_machine_spi_write_readinto(mp_obj_t self, mp_obj_t wr_buf, mp
}
MP_DEFINE_CONST_FUN_OBJ_3(mp_machine_spi_write_readinto_obj, mp_machine_spi_write_readinto);
+STATIC const mp_rom_map_elem_t machine_spi_locals_dict_table[] = {
+ { MP_ROM_QSTR(MP_QSTR_init), MP_ROM_PTR(&machine_spi_init_obj) },
+ { MP_ROM_QSTR(MP_QSTR_deinit), MP_ROM_PTR(&machine_spi_deinit_obj) },
+ { MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_machine_spi_read_obj) },
+ { MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_machine_spi_readinto_obj) },
+ { MP_ROM_QSTR(MP_QSTR_write), MP_ROM_PTR(&mp_machine_spi_write_obj) },
+ { MP_ROM_QSTR(MP_QSTR_write_readinto), MP_ROM_PTR(&mp_machine_spi_write_readinto_obj) },
+
+ { MP_ROM_QSTR(MP_QSTR_MSB), MP_ROM_INT(MICROPY_PY_MACHINE_SPI_MSB) },
+ { MP_ROM_QSTR(MP_QSTR_LSB), MP_ROM_INT(MICROPY_PY_MACHINE_SPI_LSB) },
+};
+
+MP_DEFINE_CONST_DICT(mp_machine_spi_locals_dict, machine_spi_locals_dict_table);
+
+/******************************************************************************/
+// Implementation of soft SPI
+
+STATIC uint32_t baudrate_from_delay_half(uint32_t delay_half) {
+ #ifdef MICROPY_PY_MACHINE_SPI_MIN_DELAY
+ if (delay_half == MICROPY_PY_MACHINE_SPI_MIN_DELAY) {
+ return MICROPY_PY_MACHINE_SPI_MAX_BAUDRATE;
+ } else
+ #endif
+ {
+ return 500000 / delay_half;
+ }
+}
+
+STATIC uint32_t baudrate_to_delay_half(uint32_t baudrate) {
+ #ifdef MICROPY_PY_MACHINE_SPI_MIN_DELAY
+ if (baudrate >= MICROPY_PY_MACHINE_SPI_MAX_BAUDRATE) {
+ return MICROPY_PY_MACHINE_SPI_MIN_DELAY;
+ } else
+ #endif
+ {
+ uint32_t delay_half = 500000 / baudrate;
+ // round delay_half up so that: actual_baudrate <= requested_baudrate
+ if (500000 % baudrate != 0) {
+ delay_half += 1;
+ }
+ return delay_half;
+ }
+}
+
+STATIC void mp_machine_soft_spi_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
+ mp_machine_soft_spi_obj_t *self = MP_OBJ_TO_PTR(self_in);
+ mp_printf(print, "SoftSPI(baudrate=%u, polarity=%u, phase=%u,"
+ " sck=" MP_HAL_PIN_FMT ", mosi=" MP_HAL_PIN_FMT ", miso=" MP_HAL_PIN_FMT ")",
+ baudrate_from_delay_half(self->delay_half), self->polarity, self->phase,
+ mp_hal_pin_name(self->sck), mp_hal_pin_name(self->mosi), mp_hal_pin_name(self->miso));
+}
+
+STATIC mp_obj_t mp_machine_soft_spi_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *all_args) {
+ enum { ARG_baudrate, ARG_polarity, ARG_phase, ARG_bits, ARG_firstbit, ARG_sck, ARG_mosi, ARG_miso };
+ static const mp_arg_t allowed_args[] = {
+ { MP_QSTR_baudrate, MP_ARG_INT, {.u_int = 500000} },
+ { MP_QSTR_polarity, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
+ { MP_QSTR_phase, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
+ { MP_QSTR_bits, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 8} },
+ { MP_QSTR_firstbit, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = MICROPY_PY_MACHINE_SPI_MSB} },
+ { MP_QSTR_sck, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
+ { MP_QSTR_mosi, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
+ { MP_QSTR_miso, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
+ };
+ mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
+ mp_arg_parse_all_kw_array(n_args, n_kw, all_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
+
+ // create new object
+ mp_machine_soft_spi_obj_t *self = m_new_obj(mp_machine_soft_spi_obj_t);
+ self->base.type = &mp_machine_soft_spi_type;
+
+ // set parameters
+ self->delay_half = baudrate_to_delay_half(args[ARG_baudrate].u_int);
+ self->polarity = args[ARG_polarity].u_int;
+ self->phase = args[ARG_phase].u_int;
+ if (args[ARG_bits].u_int != 8) {
+ mp_raise_ValueError("bits must be 8");
+ }
+ if (args[ARG_firstbit].u_int != MICROPY_PY_MACHINE_SPI_MSB) {
+ mp_raise_ValueError("firstbit must be MSB");
+ }
+ if (args[ARG_sck].u_obj == MP_OBJ_NULL
+ || args[ARG_mosi].u_obj == MP_OBJ_NULL
+ || args[ARG_miso].u_obj == MP_OBJ_NULL) {
+ mp_raise_ValueError("must specify all of sck/mosi/miso");
+ }
+ self->sck = mp_hal_get_pin_obj(args[ARG_sck].u_obj);
+ self->mosi = mp_hal_get_pin_obj(args[ARG_mosi].u_obj);
+ self->miso = mp_hal_get_pin_obj(args[ARG_miso].u_obj);
+
+ // configure pins
+ mp_hal_pin_write(self->sck, self->polarity);
+ mp_hal_pin_output(self->sck);
+ mp_hal_pin_output(self->mosi);
+ mp_hal_pin_input(self->miso);
+
+ return MP_OBJ_FROM_PTR(self);
+}
+
+STATIC void mp_machine_soft_spi_init(mp_obj_base_t *self_in, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
+ mp_machine_soft_spi_obj_t *self = (mp_machine_soft_spi_obj_t*)self_in;
+
+ enum { ARG_baudrate, ARG_polarity, ARG_phase, ARG_sck, ARG_mosi, ARG_miso };
+ static const mp_arg_t allowed_args[] = {
+ { MP_QSTR_baudrate, MP_ARG_INT, {.u_int = -1} },
+ { MP_QSTR_polarity, MP_ARG_INT, {.u_int = -1} },
+ { MP_QSTR_phase, MP_ARG_INT, {.u_int = -1} },
+ { MP_QSTR_sck, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
+ { MP_QSTR_mosi, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
+ { MP_QSTR_miso, MP_ARG_KW_ONLY | MP_ARG_OBJ, {.u_obj = MP_OBJ_NULL} },
+ };
+ mp_arg_val_t args[MP_ARRAY_SIZE(allowed_args)];
+ mp_arg_parse_all(n_args, pos_args, kw_args, MP_ARRAY_SIZE(allowed_args), allowed_args, args);
+
+ if (args[ARG_baudrate].u_int != -1) {
+ self->delay_half = baudrate_to_delay_half(args[ARG_baudrate].u_int);
+ }
+ if (args[ARG_polarity].u_int != -1) {
+ self->polarity = args[ARG_polarity].u_int;
+ }
+ if (args[ARG_phase].u_int != -1) {
+ self->phase = args[ARG_phase].u_int;
+ }
+ if (args[ARG_sck].u_obj != MP_OBJ_NULL) {
+ self->sck = mp_hal_get_pin_obj(args[ARG_sck].u_obj);
+ }
+ if (args[ARG_mosi].u_obj != MP_OBJ_NULL) {
+ self->mosi = mp_hal_get_pin_obj(args[ARG_mosi].u_obj);
+ }
+ if (args[ARG_miso].u_obj != MP_OBJ_NULL) {
+ self->miso = mp_hal_get_pin_obj(args[ARG_miso].u_obj);
+ }
+
+ // configure pins
+ mp_hal_pin_write(self->sck, self->polarity);
+ mp_hal_pin_output(self->sck);
+ mp_hal_pin_output(self->mosi);
+ mp_hal_pin_input(self->miso);
+}
+
+STATIC const mp_machine_spi_p_t mp_machine_soft_spi_p = {
+ .init = mp_machine_soft_spi_init,
+ .deinit = NULL,
+ .transfer = mp_machine_soft_spi_transfer,
+};
+
+const mp_obj_type_t mp_machine_soft_spi_type = {
+ { &mp_type_type },
+ .name = MP_QSTR_SoftSPI,
+ .print = mp_machine_soft_spi_print,
+ .make_new = mp_machine_spi_make_new, // delegate to master constructor
+ .protocol = &mp_machine_soft_spi_p,
+ .locals_dict = (mp_obj_dict_t*)&mp_machine_spi_locals_dict,
+};
+
#endif // MICROPY_PY_MACHINE_SPI
diff --git a/extmod/machine_spi.h b/extmod/machine_spi.h
index 62f42a885..88a3e19f4 100644
--- a/extmod/machine_spi.h
+++ b/extmod/machine_spi.h
@@ -32,6 +32,8 @@
// SPI protocol
typedef struct _mp_machine_spi_p_t {
+ void (*init)(mp_obj_base_t *obj, size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args);
+ void (*deinit)(mp_obj_base_t *obj); // can be NULL
void (*transfer)(mp_obj_base_t *obj, size_t len, const uint8_t *src, uint8_t *dest);
} mp_machine_spi_p_t;
@@ -45,8 +47,13 @@ typedef struct _mp_machine_soft_spi_obj_t {
mp_hal_pin_obj_t miso;
} mp_machine_soft_spi_obj_t;
+extern const mp_obj_type_t mp_machine_soft_spi_type;
+extern const mp_obj_dict_t mp_machine_spi_locals_dict;
+
void mp_machine_soft_spi_transfer(mp_obj_base_t *self, size_t len, const uint8_t *src, uint8_t *dest);
+mp_obj_t mp_machine_spi_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args);
+
MP_DECLARE_CONST_FUN_OBJ_VAR_BETWEEN(mp_machine_spi_read_obj);
MP_DECLARE_CONST_FUN_OBJ_VAR_BETWEEN(mp_machine_spi_readinto_obj);
MP_DECLARE_CONST_FUN_OBJ_2(mp_machine_spi_write_obj);
diff --git a/stmhal/mpconfigport.h b/stmhal/mpconfigport.h
index 9d9487a66..0e3098095 100644
--- a/stmhal/mpconfigport.h
+++ b/stmhal/mpconfigport.h
@@ -106,6 +106,7 @@
#define MICROPY_PY_MACHINE_I2C_MAKE_NEW machine_hard_i2c_make_new
#define MICROPY_PY_MACHINE_SPI (1)
#define MICROPY_PY_MACHINE_SPI_MIN_DELAY (0)
+#define MICROPY_PY_MACHINE_SPI_MAX_BAUDRATE (HAL_RCC_GetSysClockFreq() / 48)
#define MICROPY_PY_FRAMEBUF (1)
#ifndef MICROPY_PY_USOCKET
diff --git a/stmhal/mphalport.h b/stmhal/mphalport.h
index b55c9ccdc..f0c05555d 100644
--- a/stmhal/mphalport.h
+++ b/stmhal/mphalport.h
@@ -48,6 +48,7 @@ static inline mp_uint_t mp_hal_ticks_cpu(void) {
#include "stmhal/pin.h"
+#define MP_HAL_PIN_FMT "%q"
#define MP_HAL_PIN_MODE_INPUT (0)
#define MP_HAL_PIN_MODE_OUTPUT (1)
#define MP_HAL_PIN_MODE_ALT (2)
@@ -60,6 +61,7 @@ static inline mp_uint_t mp_hal_ticks_cpu(void) {
#define mp_hal_pin_obj_t const pin_obj_t*
#define mp_hal_get_pin_obj(o) pin_find(o)
+#define mp_hal_pin_name(p) ((p)->name)
#define mp_hal_pin_input(p) mp_hal_pin_config((p), MP_HAL_PIN_MODE_INPUT, MP_HAL_PIN_PULL_NONE, 0)
#define mp_hal_pin_output(p) mp_hal_pin_config((p), MP_HAL_PIN_MODE_OUTPUT, MP_HAL_PIN_PULL_NONE, 0)
#define mp_hal_pin_open_drain(p) mp_hal_pin_config((p), MP_HAL_PIN_MODE_OPEN_DRAIN, MP_HAL_PIN_PULL_NONE, 0)
--
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