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diff --git a/wirish/HardwareSPI.cpp b/wirish/HardwareSPI.cpp
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+/******************************************************************************
+ * The MIT License
+ *
+ * Copyright (c) 2010 Perry Hung.
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy,
+ * modify, merge, publish, distribute, sublicense, and/or sell copies
+ * of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *****************************************************************************/
+
+/**
+ * @author Marti Bolivar <mbolivar@leaflabs.com>
+ * @brief Wirish SPI implementation.
+ */
+
+#include <wirish/HardwareSPI.h>
+
+#include <libmaple/timer.h>
+#include <libmaple/util.h>
+#include <libmaple/rcc.h>
+
+#include <wirish/wirish.h>
+#include <wirish/boards.h>
+
+struct spi_pins {
+ uint8 nss;
+ uint8 sck;
+ uint8 miso;
+ uint8 mosi;
+};
+
+static const spi_pins* dev_to_spi_pins(spi_dev *dev);
+
+static void enable_device(spi_dev *dev,
+ bool as_master,
+ SPIFrequency frequency,
+ spi_cfg_flag endianness,
+ spi_mode mode);
+
+static const spi_pins board_spi_pins[] __FLASH__ = {
+ {BOARD_SPI1_NSS_PIN,
+ BOARD_SPI1_SCK_PIN,
+ BOARD_SPI1_MISO_PIN,
+ BOARD_SPI1_MOSI_PIN},
+ {BOARD_SPI2_NSS_PIN,
+ BOARD_SPI2_SCK_PIN,
+ BOARD_SPI2_MISO_PIN,
+ BOARD_SPI2_MOSI_PIN},
+#ifdef STM32_HIGH_DENSITY
+ {BOARD_SPI3_NSS_PIN,
+ BOARD_SPI3_SCK_PIN,
+ BOARD_SPI3_MISO_PIN,
+ BOARD_SPI3_MOSI_PIN},
+#endif
+};
+
+
+/*
+ * Constructor
+ */
+
+HardwareSPI::HardwareSPI(uint32 spi_num) {
+ switch (spi_num) {
+ case 1:
+ this->spi_d = SPI1;
+ break;
+ case 2:
+ this->spi_d = SPI2;
+ break;
+#ifdef STM32_HIGH_DENSITY
+ case 3:
+ this->spi_d = SPI3;
+ break;
+#endif
+ default:
+ ASSERT(0);
+ }
+}
+
+/*
+ * Set up/tear down
+ */
+
+void HardwareSPI::begin(SPIFrequency frequency, uint32 bitOrder, uint32 mode) {
+ if (mode >= 4) {
+ ASSERT(0);
+ return;
+ }
+ spi_cfg_flag end = bitOrder == MSBFIRST ? SPI_FRAME_MSB : SPI_FRAME_LSB;
+ spi_mode m = (spi_mode)mode;
+ enable_device(this->spi_d, true, frequency, end, m);
+}
+
+void HardwareSPI::begin(void) {
+ this->begin(SPI_1_125MHZ, MSBFIRST, 0);
+}
+
+void HardwareSPI::beginSlave(uint32 bitOrder, uint32 mode) {
+ if (mode >= 4) {
+ ASSERT(0);
+ return;
+ }
+ spi_cfg_flag end = bitOrder == MSBFIRST ? SPI_FRAME_MSB : SPI_FRAME_LSB;
+ spi_mode m = (spi_mode)mode;
+ enable_device(this->spi_d, false, (SPIFrequency)0, end, m);
+}
+
+void HardwareSPI::beginSlave(void) {
+ this->beginSlave(MSBFIRST, 0);
+}
+
+void HardwareSPI::end(void) {
+ if (!spi_is_enabled(this->spi_d)) {
+ return;
+ }
+
+ // Follows RM0008's sequence for disabling a SPI in master/slave
+ // full duplex mode.
+ while (spi_is_rx_nonempty(this->spi_d)) {
+ // FIXME [0.1.0] remove this once you have an interrupt based driver
+ volatile uint16 rx __attribute__((unused)) = spi_rx_reg(this->spi_d);
+ }
+ while (!spi_is_tx_empty(this->spi_d))
+ ;
+ while (spi_is_busy(this->spi_d))
+ ;
+ spi_peripheral_disable(this->spi_d);
+}
+
+/*
+ * I/O
+ */
+
+uint8 HardwareSPI::read(void) {
+ uint8 buf[1];
+ this->read(buf, 1);
+ return buf[0];
+}
+
+void HardwareSPI::read(uint8 *buf, uint32 len) {
+ uint32 rxed = 0;
+ while (rxed < len) {
+ while (!spi_is_rx_nonempty(this->spi_d))
+ ;
+ buf[rxed++] = (uint8)spi_rx_reg(this->spi_d);
+ }
+}
+
+void HardwareSPI::write(uint8 byte) {
+ this->write(&byte, 1);
+}
+
+void HardwareSPI::write(const uint8 *data, uint32 length) {
+ uint32 txed = 0;
+ while (txed < length) {
+ txed += spi_tx(this->spi_d, data + txed, length - txed);
+ }
+}
+
+uint8 HardwareSPI::transfer(uint8 byte) {
+ this->write(byte);
+ return this->read();
+}
+
+/*
+ * Pin accessors
+ */
+
+uint8 HardwareSPI::misoPin(void) {
+ return dev_to_spi_pins(this->spi_d)->miso;
+}
+
+uint8 HardwareSPI::mosiPin(void) {
+ return dev_to_spi_pins(this->spi_d)->mosi;
+}
+
+uint8 HardwareSPI::sckPin(void) {
+ return dev_to_spi_pins(this->spi_d)->sck;
+}
+
+uint8 HardwareSPI::nssPin(void) {
+ return dev_to_spi_pins(this->spi_d)->nss;
+}
+
+/*
+ * Deprecated functions
+ */
+
+uint8 HardwareSPI::send(uint8 data) {
+ uint8 buf[] = {data};
+ return this->send(buf, 1);
+}
+
+uint8 HardwareSPI::send(uint8 *buf, uint32 len) {
+ uint32 txed = 0;
+ uint8 ret = 0;
+ while (txed < len) {
+ this->write(buf[txed++]);
+ ret = this->read();
+ }
+ return ret;
+}
+
+uint8 HardwareSPI::recv(void) {
+ return this->read();
+}
+
+/*
+ * Auxiliary functions
+ */
+
+static void configure_gpios(spi_dev *dev, bool as_master);
+static spi_baud_rate determine_baud_rate(spi_dev *dev, SPIFrequency freq);
+
+static const spi_pins* dev_to_spi_pins(spi_dev *dev) {
+ switch (dev->clk_id) {
+ case RCC_SPI1: return board_spi_pins;
+ case RCC_SPI2: return board_spi_pins + 1;
+#ifdef STM32_HIGH_DENSITY
+ case RCC_SPI3: return board_spi_pins + 2;
+#endif
+ default: return NULL;
+ }
+}
+
+/* Enables the device in master or slave full duplex mode. If you
+ * change this code, you must ensure that appropriate changes are made
+ * to HardwareSPI::end(). */
+static void enable_device(spi_dev *dev,
+ bool as_master,
+ SPIFrequency freq,
+ spi_cfg_flag endianness,
+ spi_mode mode) {
+ spi_baud_rate baud = determine_baud_rate(dev, freq);
+ uint32 cfg_flags = (endianness | SPI_DFF_8_BIT | SPI_SW_SLAVE |
+ (as_master ? SPI_SOFT_SS : 0));
+
+ spi_init(dev);
+ configure_gpios(dev, as_master);
+ if (as_master) {
+ spi_master_enable(dev, baud, mode, cfg_flags);
+ } else {
+ spi_slave_enable(dev, mode, cfg_flags);
+ }
+}
+
+static void disable_pwm(const stm32_pin_info *i) {
+ if (i->timer_device) {
+ timer_set_mode(i->timer_device, i->timer_channel, TIMER_DISABLED);
+ }
+}
+
+static void configure_gpios(spi_dev *dev, bool as_master) {
+ const spi_pins *pins = dev_to_spi_pins(dev);
+
+ if (!pins) {
+ return;
+ }
+
+ const stm32_pin_info *nssi = &PIN_MAP[pins->nss];
+ const stm32_pin_info *scki = &PIN_MAP[pins->sck];
+ const stm32_pin_info *misoi = &PIN_MAP[pins->miso];
+ const stm32_pin_info *mosii = &PIN_MAP[pins->mosi];
+
+ disable_pwm(nssi);
+ disable_pwm(scki);
+ disable_pwm(misoi);
+ disable_pwm(mosii);
+
+ spi_config_gpios(dev, as_master, nssi->gpio_device, nssi->gpio_bit,
+ scki->gpio_device, scki->gpio_bit, misoi->gpio_bit,
+ mosii->gpio_bit);
+}
+
+static const spi_baud_rate baud_rates[MAX_SPI_FREQS] __FLASH__ = {
+ SPI_BAUD_PCLK_DIV_2,
+ SPI_BAUD_PCLK_DIV_4,
+ SPI_BAUD_PCLK_DIV_8,
+ SPI_BAUD_PCLK_DIV_16,
+ SPI_BAUD_PCLK_DIV_32,
+ SPI_BAUD_PCLK_DIV_64,
+ SPI_BAUD_PCLK_DIV_128,
+ SPI_BAUD_PCLK_DIV_256,
+};
+
+/*
+ * Note: This assumes you're on a LeafLabs-style board
+ * (CYCLES_PER_MICROSECOND == 72, APB2 at 72MHz, APB1 at 36MHz).
+ */
+static spi_baud_rate determine_baud_rate(spi_dev *dev, SPIFrequency freq) {
+ if (rcc_dev_clk(dev->clk_id) == RCC_APB2 && freq == SPI_140_625KHZ) {
+ /* APB2 peripherals are too fast for 140.625 KHz */
+ ASSERT(0);
+ return (spi_baud_rate)~0;
+ }
+ return (rcc_dev_clk(dev->clk_id) == RCC_APB2 ?
+ baud_rates[freq + 1] :
+ baud_rates[freq]);
+}
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