From 5bb28c7f10ebd1036302cf7ac0b24a7a233de2aa Mon Sep 17 00:00:00 2001
From: Damien George <damien.p.george@gmail.com>
Date: Mon, 3 Oct 2016 12:39:31 +1100
Subject: [PATCH] extmod/machine_spi: Simplify SPI xfer function to only take
one buf len.
There is no need to take src_len and dest_len arguments. The case of
reading-only with a single output byte (originally src_len=1, dest_len>1)
is now handled by using the output buffer as the input buffer, and using
memset to fill the output byte into this buffer. This simplifies the
implementations of the spi_transfer protocol function.
---
esp8266/modpybhspi.c | 32 ++++++++++----------------------
esp8266/modpybspi.c | 15 +++++----------
extmod/machine_spi.c | 25 ++++++++++---------------
extmod/machine_spi.h | 2 +-
stmhal/spi.c | 11 ++---------
5 files changed, 28 insertions(+), 57 deletions(-)
diff --git a/esp8266/modpybhspi.c b/esp8266/modpybhspi.c
index c1cd7f662..10a090269 100644
--- a/esp8266/modpybhspi.c
+++ b/esp8266/modpybhspi.c
@@ -50,23 +50,23 @@ typedef struct _pyb_hspi_obj_t {
} pyb_hspi_obj_t;
-STATIC void hspi_transfer(mp_obj_base_t *self_in, size_t src_len, const uint8_t *src_buf, size_t dest_len, uint8_t *dest_buf) {
+STATIC void hspi_transfer(mp_obj_base_t *self_in, size_t len, const uint8_t *src, uint8_t *dest) {
(void)self_in;
- if (dest_len == 0) {
+ if (dest == NULL) {
// fast case when we only need to write data
size_t chunk_size = 1024;
- size_t count = src_len / chunk_size;
+ size_t count = len / chunk_size;
size_t i = 0;
for (size_t j = 0; j < count; ++j) {
for (size_t k = 0; k < chunk_size; ++k) {
- spi_tx8fast(HSPI, src_buf[i]);
+ spi_tx8fast(HSPI, src[i]);
++i;
}
ets_loop_iter();
}
- while (i < src_len) {
- spi_tx8fast(HSPI, src_buf[i]);
+ while (i < len) {
+ spi_tx8fast(HSPI, src[i]);
++i;
}
} else {
@@ -74,29 +74,17 @@ STATIC void hspi_transfer(mp_obj_base_t *self_in, size_t src_len, const uint8_t
// Process data in chunks, let the pending tasks run in between
size_t chunk_size = 1024; // TODO this should depend on baudrate
- size_t count = dest_len / chunk_size;
+ size_t count = len / chunk_size;
size_t i = 0;
for (size_t j = 0; j < count; ++j) {
for (size_t k = 0; k < chunk_size; ++k) {
- uint32_t data_out;
- if (src_len == 1) {
- data_out = src_buf[0];
- } else {
- data_out = src_buf[i];
- }
- dest_buf[i] = spi_transaction(HSPI, 0, 0, 0, 0, 8, data_out, 8, 0);
+ dest[i] = spi_transaction(HSPI, 0, 0, 0, 0, 8, src[i], 8, 0);
++i;
}
ets_loop_iter();
}
- while (i < dest_len) {
- uint32_t data_out;
- if (src_len == 1) {
- data_out = src_buf[0];
- } else {
- data_out = src_buf[i];
- }
- dest_buf[i] = spi_transaction(HSPI, 0, 0, 0, 0, 8, data_out, 8, 0);
+ while (i < len) {
+ dest[i] = spi_transaction(HSPI, 0, 0, 0, 0, 8, src[i], 8, 0);
++i;
}
}
diff --git a/esp8266/modpybspi.c b/esp8266/modpybspi.c
index 4c4b843c5..b9650954f 100644
--- a/esp8266/modpybspi.c
+++ b/esp8266/modpybspi.c
@@ -47,17 +47,12 @@ typedef struct _pyb_spi_obj_t {
mp_hal_pin_obj_t miso;
} pyb_spi_obj_t;
-STATIC void mp_hal_spi_transfer(mp_obj_base_t *self_in, size_t src_len, const uint8_t *src_buf, size_t dest_len, uint8_t *dest_buf) {
+STATIC void mp_hal_spi_transfer(mp_obj_base_t *self_in, size_t len, const uint8_t *src, uint8_t *dest) {
pyb_spi_obj_t *self = (pyb_spi_obj_t*)self_in;
// only MSB transfer is implemented
uint32_t delay_half = 500000 / self->baudrate + 1;
- for (size_t i = 0; i < src_len || i < dest_len; ++i) {
- uint8_t data_out;
- if (src_len == 1) {
- data_out = src_buf[0];
- } else {
- data_out = src_buf[i];
- }
+ for (size_t i = 0; i < len; ++i) {
+ uint8_t data_out = src[i];
uint8_t data_in = 0;
for (int j = 0; j < 8; ++j, data_out <<= 1) {
mp_hal_pin_write(self->mosi, (data_out >> 7) & 1);
@@ -77,8 +72,8 @@ STATIC void mp_hal_spi_transfer(mp_obj_base_t *self_in, size_t src_len, const ui
ets_delay_us(delay_half);
}
}
- if (dest_len != 0) {
- dest_buf[i] = data_in;
+ if (dest != NULL) {
+ dest[i] = data_in;
}
// make sure pending tasks have a chance to run
ets_loop_iter();
diff --git a/extmod/machine_spi.c b/extmod/machine_spi.c
index 6b6202a22..1c64cf511 100644
--- a/extmod/machine_spi.c
+++ b/extmod/machine_spi.c
@@ -25,26 +25,24 @@
*/
#include <stdio.h>
+#include <string.h>
#include "py/runtime.h"
#include "extmod/machine_spi.h"
#if MICROPY_PY_MACHINE_SPI
-STATIC void mp_machine_spi_transfer(mp_obj_t self, size_t slen, const uint8_t *src, size_t dlen, uint8_t *dest) {
+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;
- spi_p->transfer(s, slen, src, dlen, dest);
+ spi_p->transfer(s, len, src, dest);
}
STATIC mp_obj_t mp_machine_spi_read(size_t n_args, const mp_obj_t *args) {
- uint8_t write_byte = 0;
- if (n_args == 3) {
- write_byte = mp_obj_get_int(args[2]);
- }
vstr_t vstr;
vstr_init_len(&vstr, mp_obj_get_int(args[1]));
- mp_machine_spi_transfer(args[0], 1, &write_byte, vstr.len, (uint8_t*)vstr.buf);
+ memset(vstr.buf, n_args == 3 ? mp_obj_get_int(args[2]) : 0, vstr.len);
+ mp_machine_spi_transfer(args[0], vstr.len, vstr.buf, vstr.buf);
return mp_obj_new_str_from_vstr(&mp_type_bytes, &vstr);
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_machine_spi_read_obj, 2, 3, mp_machine_spi_read);
@@ -52,11 +50,8 @@ MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_machine_spi_read_obj, 2, 3, mp_machine_sp
STATIC mp_obj_t mp_machine_spi_readinto(size_t n_args, const mp_obj_t *args) {
mp_buffer_info_t bufinfo;
mp_get_buffer_raise(args[1], &bufinfo, MP_BUFFER_WRITE);
- uint8_t write_byte = 0;
- if (n_args == 3) {
- write_byte = mp_obj_get_int(args[2]);
- }
- mp_machine_spi_transfer(args[0], 1, &write_byte, bufinfo.len, (uint8_t*)bufinfo.buf);
+ memset(bufinfo.buf, n_args == 3 ? mp_obj_get_int(args[2]) : 0, bufinfo.len);
+ mp_machine_spi_transfer(args[0], bufinfo.len, bufinfo.buf, bufinfo.buf);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_machine_spi_readinto_obj, 2, 3, mp_machine_spi_readinto);
@@ -64,7 +59,7 @@ MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mp_machine_spi_readinto_obj, 2, 3, mp_machin
STATIC mp_obj_t mp_machine_spi_write(mp_obj_t self, mp_obj_t wr_buf) {
mp_buffer_info_t src;
mp_get_buffer_raise(wr_buf, &src, MP_BUFFER_READ);
- mp_machine_spi_transfer(self, src.len, (const uint8_t*)src.buf, 0, NULL);
+ mp_machine_spi_transfer(self, src.len, (const uint8_t*)src.buf, NULL);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_2(mp_machine_spi_write_obj, mp_machine_spi_write);
@@ -75,9 +70,9 @@ STATIC mp_obj_t mp_machine_spi_write_readinto(mp_obj_t self, mp_obj_t wr_buf, mp
mp_buffer_info_t dest;
mp_get_buffer_raise(rd_buf, &dest, MP_BUFFER_WRITE);
if (src.len != dest.len) {
- nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "buffers must be the same length"));
+ mp_raise_ValueError("buffers must be the same length");
}
- mp_machine_spi_transfer(self, src.len, (const uint8_t*)src.buf, dest.len, (uint8_t*)dest.buf);
+ mp_machine_spi_transfer(self, src.len, src.buf, dest.buf);
return mp_const_none;
}
MP_DEFINE_CONST_FUN_OBJ_3(mp_machine_spi_write_readinto_obj, mp_machine_spi_write_readinto);
diff --git a/extmod/machine_spi.h b/extmod/machine_spi.h
index 26d716fc1..35a911d91 100644
--- a/extmod/machine_spi.h
+++ b/extmod/machine_spi.h
@@ -31,7 +31,7 @@
// SPI protocol
typedef struct _mp_machine_spi_p_t {
- void (*transfer)(mp_obj_base_t *obj, size_t slen, const uint8_t *src, size_t dlen, uint8_t *dest);
+ void (*transfer)(mp_obj_base_t *obj, size_t len, const uint8_t *src, uint8_t *dest);
} mp_machine_spi_p_t;
MP_DECLARE_CONST_FUN_OBJ(mp_machine_spi_read_obj);
diff --git a/stmhal/spi.c b/stmhal/spi.c
index 85f170920..05b9b629c 100644
--- a/stmhal/spi.c
+++ b/stmhal/spi.c
@@ -401,15 +401,8 @@ STATIC void spi_transfer(mp_obj_base_t *self_in, size_t src_len, const uint8_t *
}
}
-STATIC void spi_transfer_machine(mp_obj_base_t *self_in, size_t src_len, const uint8_t *src_buf, size_t dest_len, uint8_t *dest_buf) {
- if (src_len == 1 && dest_len > 1) {
- // this catches read and readinto
- // copy the single output byte to the dest buffer and use that as source
- memset(dest_buf, src_buf[0], dest_len);
- src_len = dest_len;
- src_buf = dest_buf;
- }
- spi_transfer(self_in, src_len, src_buf, dest_len, dest_buf, 100);
+STATIC void spi_transfer_machine(mp_obj_base_t *self_in, size_t len, const uint8_t *src, uint8_t *dest) {
+ spi_transfer(self_in, len, src, dest == NULL ? 0 : len, dest, 100);
}
/******************************************************************************/
--
GitLab