+++ /dev/null
-#
-# Copyright (C) 2009 OpenWrt.org
-#
-# This is free software, licensed under the GNU General Public License v2.
-# See /LICENSE for more information.
-
-include $(TOPDIR)/rules.mk
-
-PKG_NAME:=ucmb-tools
-PKG_RELEASE:=1
-
-include $(INCLUDE_DIR)/package.mk
-
-
-define Package/ucmb-tools
- SECTION:=utils
- CATEGORY:=Utilities
- TITLE:=Microcontroller Message Bus tools
- DEPENDS:=+kmod-ucmb
- MAINTAINER:=Michael Buesch <mb@bu3sch.de>
-endef
-
-define Package/ucmb-tools/description
- Debugging tool for UCMB
-endef
-
-define Build/Prepare
- $(CP) ./tools/* $(PKG_BUILD_DIR)/
-endef
-
-define Build/Compile
- $(MAKE) -C $(PKG_BUILD_DIR) \
- $(TARGET_CONFIGURE_OPTS) CFLAGS="$(TARGET_CFLAGS) -I$(LINUX_DIR)/include"
-endef
-
-define Package/ucmb-tools/install
- $(INSTALL_DIR) $(1)/usr/bin
- $(INSTALL_BIN) $(PKG_BUILD_DIR)/ucmb $(1)/usr/bin/
-endef
-
-$(eval $(call BuildPackage,ucmb-tools))
+++ /dev/null
-INSTDIR = $(prefix)/usr/bin
-
-all: ucmb
-
-ucmb: ucmb.o
- $(CC) $(CFLAGS) $(LDFLAGS) $^ $(LDLIBS) -o $@
- $(STRIP) $@
-
-%.o: %.c
- $(CC) -c $(CFLAGS) $^ -o $@
-
-install: ucmb
- $(INSTALL) -d $(INSTDIR)
- $(INSTALL) -m 0755 -o 0 -g 0 ucmb $(INSTDIR)
-
-clean:
- rm -f ucmb *.o
+++ /dev/null
-/*
- * Microcontroller Message Bus
- * Userspace commandline utility
- *
- * Copyright (c) 2009 Michael Buesch <mb@bu3sch.de>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <errno.h>
-#include <sys/ioctl.h>
-#include <linux/ioctl.h>
-
-
-#define UCMB_DEV "/dev/ucmb"
-
-#define __UCMB_IOCTL ('U'|'C'|'M'|'B')
-#define UCMB_IOCTL_RESETUC _IO(__UCMB_IOCTL, 0)
-#define UCMB_IOCTL_GMSGDELAY _IOR(__UCMB_IOCTL, 1, unsigned int)
-#define UCMB_IOCTL_SMSGDELAY _IOW(__UCMB_IOCTL, 2, unsigned int)
-
-
-static void usage(int argc, char **argv)
-{
- fprintf(stderr, "Usage: %s read|write|reset [" UCMB_DEV "]\n", argv[0]);
-}
-
-int main(int argc, char **argv)
-{
- const char *command, *devpath = UCMB_DEV;
- int res, errcode = 0;
- int ucmb_fd;
- char *buf;
- size_t count, buflen;
- ssize_t nrbytes;
-
- if (argc != 2 && argc != 3) {
- usage(argc, argv);
- return 1;
- }
- if (argc == 3)
- devpath = argv[2];
- command = argv[1];
-
- ucmb_fd = open(devpath, O_RDWR);
- if (ucmb_fd == -1) {
- fprintf(stderr, "Failed to open %s\n", UCMB_DEV);
- errcode = 1;
- goto out;
- }
-
- buflen = 4096;
- buf = malloc(buflen);
- if (!buf) {
- fprintf(stderr, "Out of memory\n");
- errcode = 1;
- goto out_close;
- }
-
- if (strcasecmp(command, "read") == 0) {
- nrbytes = read(ucmb_fd, buf, buflen);
- if (nrbytes < 0) {
- fprintf(stderr, "Failed to read UCMB: %s (%d)\n",
- strerror(errno), errno);
- errcode = 1;
- goto out_free;
- }
- if (fwrite(buf, nrbytes, 1, stdout) != 1) {
- fprintf(stderr, "Failed to write stdout\n");
- errcode = 1;
- goto out_free;
- }
- } else if (strcasecmp(command, "write") == 0) {
- count = fread(buf, 1, buflen, stdin);
- if (!count) {
- fprintf(stderr, "Failed to read stdin\n");
- errcode = 1;
- goto out_free;
- }
- nrbytes = write(ucmb_fd, buf, count);
- if (nrbytes != count) {
- fprintf(stderr, "Failed to write UCMB: %s (%d)\n",
- strerror(errno), errno);
- errcode = 1;
- goto out_free;
- }
- } else if (strcasecmp(command, "reset") == 0) {
- res = ioctl(ucmb_fd, UCMB_IOCTL_RESETUC);
- if (res) {
- fprintf(stderr, "RESET ioctl failed: %s (%d)\n",
- strerror(res < 0 ? -res : res), res);
- errcode = 1;
- goto out_free;
- }
- } else {
- usage(argc, argv);
- errcode = 1;
- goto out_free;
- }
-
-out_free:
- free(buf);
-out_close:
- close(ucmb_fd);
-out:
- return errcode;
-}
+++ /dev/null
-#
-# Copyright (C) 2010 OpenWrt.org
-#
-# This is free software, licensed under the GNU General Public License v2.
-# See /LICENSE for more information.
-
-include $(TOPDIR)/rules.mk
-include $(INCLUDE_DIR)/kernel.mk
-
-PKG_NAME:=ucmb
-PKG_RELEASE:=2
-
-include $(INCLUDE_DIR)/package.mk
-
-
-define KernelPackage/ucmb
- SUBMENU:=Other modules
- DEPENDS:=@!LINUX_2_4 \
- @!LINUX_2_6_21 @!LINUX_2_6_22 @!LINUX_2_6_23 @!LINUX_2_6_24 \
- @!LINUX_2_6_25 @!LINUX_2_6_26 @!LINUX_2_6_27 \
- +kmod-spi-gpio +kmod-crc16
- KCONFIG:=CONFIG_SPI=y \
- CONFIG_SPI_MASTER=y
- TITLE:=Microcontroller Message Bus
- FILES:=$(PKG_BUILD_DIR)/ucmb.$(LINUX_KMOD_SUFFIX)
- AUTOLOAD:=$(call AutoLoad,93,ucmb)
- MAINTAINER:=Michael Buesch <mb@bu3sch.de>
-endef
-
-define KernelPackage/ucmb/description
- The Microcontroller Message Bus is a tiny SPI-GPIO based communication
- channel used to talk to microcontrollers over GPIO pins.
- The lowlevel protocol is CRC16 protected, so one can be pretty sure
- that the data transmitted and received through the /dev/ucmb node is not corrupted.
- So no further checks should be needed at upper protocol layers.
- The device node considers every read/write to be one packet. The maximum packet
- size is either PAGE_SIZE (at least 4kb) or the microcontroller specific packet size
- limit, which is likely to be a lot smaller than PAGE_SIZE.
- To register an ucmb device, simply create a struct ucmb_platform_data
- and register it via ucmb_device_register() from another kernel module.
- Example implementations for the microcontroller-side code can be found in
- the utils/ucmb/microcontroller_examples subdirectory of the OpenWRT packages feed.
-endef
-
-define Build/Prepare
- $(CP) ./driver/* $(PKG_BUILD_DIR)/
-endef
-
-define Build/Compile
- $(MAKE) -C "$(LINUX_DIR)" \
- CROSS_COMPILE="$(TARGET_CROSS)" \
- ARCH="$(LINUX_KARCH)" \
- SUBDIRS="$(PKG_BUILD_DIR)" \
- EXTRA_CFLAGS="$(BUILDFLAGS)" \
- modules
-endef
-
-define Build/InstallDev
- $(INSTALL_DIR) $(1)/usr/include
- $(CP) \
- $(PKG_BUILD_DIR)/ucmb.h \
- $(1)/usr/include
-endef
-
-$(eval $(call KernelPackage,ucmb))
+++ /dev/null
-obj-m := ucmb.o
+++ /dev/null
-/*
- * Microcontroller Message Bus
- * Linux kernel driver
- *
- * Copyright (c) 2009-2010 Michael Buesch <mb@bu3sch.de>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-#include "ucmb.h"
-
-#include <linux/version.h>
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/miscdevice.h>
-#include <linux/fs.h>
-#include <linux/spi/spi.h>
-#include <linux/spi/spi_gpio.h>
-#include <linux/spi/spi_bitbang.h>
-#include <linux/gpio.h>
-#include <linux/gfp.h>
-#include <linux/delay.h>
-#include <linux/crc16.h>
-#include <linux/sched.h>
-
-#include <asm/uaccess.h>
-
-
-#define PFX "ucmb: "
-
-#undef DEBUG
-
-
-MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("Microcontroller Message Bus");
-MODULE_AUTHOR("Michael Buesch");
-
-
-struct ucmb {
- struct mutex mutex;
-
- bool is_open;
-
- unsigned int chunk_size;
- unsigned int msg_delay_usec;
- unsigned int gpio_reset;
- bool reset_activelow;
-
- /* Misc character device driver */
- struct miscdevice mdev;
- struct file_operations mdev_fops;
-
- /* SPI driver */
- struct spi_device *sdev;
-
- /* SPI-GPIO driver */
- struct spi_gpio_platform_data spi_gpio_pdata;
- struct platform_device spi_gpio_pdev;
-};
-
-#define UCMB_MAX_MSG_DELAY (10 * 1000 * 1000) /* 10 seconds */
-
-
-struct ucmb_message_hdr {
- __le16 magic; /* UCMB_MAGIC */
- __le16 len; /* Payload length (excluding header and footer) */
-} __attribute__((packed));
-
-struct ucmb_message_footer {
- __le16 crc; /* CRC of the header + payload. */
-} __attribute__((packed));
-
-struct ucmb_status {
- __le16 magic; /* UCMB_MAGIC */
- __le16 code; /* enum ucmb_status_code */
-} __attribute__((packed));
-
-#define UCMB_MAGIC 0x1337
-
-enum ucmb_status_code {
- UCMB_STAT_OK = 0,
- UCMB_STAT_EPROTO, /* Protocol format error */
- UCMB_STAT_ENOMEM, /* Out of memory */
- UCMB_STAT_E2BIG, /* Message too big */
- UCMB_STAT_ECRC, /* CRC error */
-};
-
-
-static int ucmb_spi_busnum_count = 1337;
-static int ucmb_pdev_id_count;
-
-
-static int __devinit ucmb_spi_probe(struct spi_device *sdev)
-{
- return 0;
-}
-
-static int __devexit ucmb_spi_remove(struct spi_device *sdev)
-{
- return 0;
-}
-
-static struct spi_driver ucmb_spi_driver = {
- .driver = {
- .name = "ucmb",
- .bus = &spi_bus_type,
- .owner = THIS_MODULE,
- },
- .probe = ucmb_spi_probe,
- .remove = __devexit_p(ucmb_spi_remove),
-};
-
-static void ucmb_toggle_reset_line(struct ucmb *ucmb, bool active)
-{
- if (ucmb->reset_activelow)
- active = !active;
- gpio_set_value(ucmb->gpio_reset, active);
-}
-
-static int ucmb_reset_microcontroller(struct ucmb *ucmb)
-{
- if (ucmb->gpio_reset == UCMB_NO_RESET)
- return -ENODEV;
-
- ucmb_toggle_reset_line(ucmb, 1);
- msleep(50);
- ucmb_toggle_reset_line(ucmb, 0);
- msleep(50);
-
- return 0;
-}
-
-static int ucmb_status_code_to_errno(enum ucmb_status_code code)
-{
- switch (code) {
- case UCMB_STAT_OK:
- return 0;
- case UCMB_STAT_EPROTO:
- return -EPROTO;
- case UCMB_STAT_ENOMEM:
- return -ENOMEM;
- case UCMB_STAT_E2BIG:
- return -E2BIG;
- case UCMB_STAT_ECRC:
- return -EBADMSG;
- }
- return -EBUSY;
-}
-
-static inline struct ucmb * filp_to_ucmb(struct file *filp)
-{
- return container_of(filp->f_op, struct ucmb, mdev_fops);
-}
-
-static int ucmb_open(struct inode *inode, struct file *filp)
-{
- struct ucmb *ucmb = filp_to_ucmb(filp);
- int err = 0;
-
- mutex_lock(&ucmb->mutex);
-
- if (ucmb->is_open) {
- err = -EBUSY;
- goto out_unlock;
- }
- ucmb->is_open = 1;
- ucmb->msg_delay_usec = 0;
-
-out_unlock:
- mutex_unlock(&ucmb->mutex);
-
- return err;
-}
-
-static int ucmb_release(struct inode *inode, struct file *filp)
-{
- struct ucmb *ucmb = filp_to_ucmb(filp);
-
- mutex_lock(&ucmb->mutex);
- WARN_ON(!ucmb->is_open);
- ucmb->is_open = 0;
- mutex_unlock(&ucmb->mutex);
-
- return 0;
-}
-
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,36)
-static long ucmb_ioctl(struct file *filp,
- unsigned int cmd, unsigned long arg)
-#else
-static int ucmb_ioctl(struct inode *inode, struct file *filp,
- unsigned int cmd, unsigned long arg)
-#endif
-{
- struct ucmb *ucmb = filp_to_ucmb(filp);
- int ret = 0;
-
- mutex_lock(&ucmb->mutex);
- switch (cmd) {
- case UCMB_IOCTL_RESETUC:
- ret = ucmb_reset_microcontroller(ucmb);
- break;
- case UCMB_IOCTL_GMSGDELAY:
- if (put_user(ucmb->msg_delay_usec, (unsigned int __user *)arg)) {
- ret = -EFAULT;
- break;
- }
- break;
- case UCMB_IOCTL_SMSGDELAY: {
- unsigned int msg_delay_usec;
-
- if (get_user(msg_delay_usec, (unsigned int __user *)arg)) {
- ret = -EFAULT;
- break;
- }
- if (msg_delay_usec > UCMB_MAX_MSG_DELAY) {
- ret = -E2BIG;
- break;
- }
- ucmb->msg_delay_usec = msg_delay_usec;
- break;
- }
- default:
- ret = -EINVAL;
- }
- mutex_unlock(&ucmb->mutex);
-
- return ret;
-}
-
-static int ucmb_spi_write(struct ucmb *ucmb, const void *_buf, size_t size)
-{
- const u8 *buf = _buf;
- size_t i, chunk_size, current_size;
- int err = 0;
-
- chunk_size = ucmb->chunk_size ? : size;
- for (i = 0; i < size; i += chunk_size) {
- current_size = chunk_size;
- if (i + current_size > size)
- current_size = size - i;
- err = spi_write(ucmb->sdev, buf + i, current_size);
- if (err)
- goto out;
- if (ucmb->chunk_size && need_resched())
- msleep(1);
- }
-out:
- return err;
-}
-
-static int ucmb_spi_read(struct ucmb *ucmb, void *_buf, size_t size)
-{
- u8 *buf = _buf;
- size_t i, chunk_size, current_size;
- int err = 0;
-
- chunk_size = ucmb->chunk_size ? : size;
- for (i = 0; i < size; i += chunk_size) {
- current_size = chunk_size;
- if (i + current_size > size)
- current_size = size - i;
- err = spi_read(ucmb->sdev, buf + i, current_size);
- if (err)
- goto out;
- if (ucmb->chunk_size && need_resched())
- msleep(1);
- }
-out:
- return err;
-}
-
-static ssize_t ucmb_read(struct file *filp, char __user *user_buf,
- size_t size, loff_t *offp)
-{
- struct ucmb *ucmb = filp_to_ucmb(filp);
- u8 *buf;
- int res, err;
- struct ucmb_message_hdr hdr;
- struct ucmb_message_footer footer;
- struct ucmb_status status = { .magic = cpu_to_le16(UCMB_MAGIC), };
- u16 crc = 0xFFFF;
-
- mutex_lock(&ucmb->mutex);
-
- size = min_t(size_t, size, PAGE_SIZE);
-
- err = -ENOMEM;
- buf = (char *)__get_free_page(GFP_KERNEL);
- if (!buf)
- goto out;
-
- err = ucmb_spi_read(ucmb, &hdr, sizeof(hdr));
- if (err)
- goto out_free;
-#ifdef DEBUG
- printk(KERN_DEBUG PFX "Received message header 0x%04X 0x%04X\n",
- le16_to_cpu(hdr.magic), le16_to_cpu(hdr.len));
-#endif
- err = -EPROTO;
- if (hdr.magic != cpu_to_le16(UCMB_MAGIC))
- goto out_free;
- err = -ENOBUFS;
- if (size < le16_to_cpu(hdr.len))
- goto out_free;
- size = le16_to_cpu(hdr.len);
- err = ucmb_spi_read(ucmb, buf, size);
- if (err)
- goto out_free;
- err = ucmb_spi_read(ucmb, &footer, sizeof(footer));
- if (err)
- goto out_free;
-
- crc = crc16(crc, (u8 *)&hdr, sizeof(hdr));
- crc = crc16(crc, buf, size);
- crc ^= 0xFFFF;
- if (crc != le16_to_cpu(footer.crc)) {
- err = -EPROTO;
- status.code = UCMB_STAT_ECRC;
- goto out_send_status;
- }
-
- if (copy_to_user(user_buf, buf, size)) {
- err = -EFAULT;
- status.code = UCMB_STAT_ENOMEM;
- goto out_send_status;
- }
-
- status.code = UCMB_STAT_OK;
- err = 0;
-
-out_send_status:
- res = ucmb_spi_write(ucmb, &status, sizeof(status));
- if (res && !err)
- err = res;
-out_free:
- free_page((unsigned long)buf);
-out:
- mutex_unlock(&ucmb->mutex);
-
- return err ? err : size;
-}
-
-static ssize_t ucmb_write(struct file *filp, const char __user *user_buf,
- size_t size, loff_t *offp)
-{
- struct ucmb *ucmb = filp_to_ucmb(filp);
- u8 *buf;
- int err;
- struct ucmb_message_hdr hdr = { .magic = cpu_to_le16(UCMB_MAGIC), };
- struct ucmb_message_footer footer = { .crc = 0xFFFF, };
- struct ucmb_status status;
-
- mutex_lock(&ucmb->mutex);
-
- err = -ENOMEM;
- buf = (char *)__get_free_page(GFP_KERNEL);
- if (!buf)
- goto out;
-
- size = min_t(size_t, PAGE_SIZE, size);
- err = -EFAULT;
- if (copy_from_user(buf, user_buf, size))
- goto out_free;
- hdr.len = cpu_to_le16(size);
-
- footer.crc = crc16(footer.crc, (u8 *)&hdr, sizeof(hdr));
- footer.crc = crc16(footer.crc, buf, size);
- footer.crc ^= 0xFFFF;
-
- err = ucmb_spi_write(ucmb, &hdr, sizeof(hdr));
- if (err)
- goto out_free;
- err = ucmb_spi_write(ucmb, buf, size);
- if (err)
- goto out_free;
- err = ucmb_spi_write(ucmb, &footer, sizeof(footer));
- if (err)
- goto out_free;
-
- if (ucmb->msg_delay_usec) {
- /* The microcontroller deserves some time to process the message. */
- if (ucmb->msg_delay_usec >= 1000000) {
- ssleep(ucmb->msg_delay_usec / 1000000);
- msleep(DIV_ROUND_UP(ucmb->msg_delay_usec % 1000000, 1000));
- } else if (ucmb->msg_delay_usec >= 1000) {
- msleep(DIV_ROUND_UP(ucmb->msg_delay_usec, 1000));
- } else
- udelay(ucmb->msg_delay_usec);
- }
-
- /* Get the status code. */
- err = ucmb_spi_read(ucmb, &status, sizeof(status));
- if (err)
- goto out_free;
-#ifdef DEBUG
- printk(KERN_DEBUG PFX "Sent message. Status report: 0x%04X 0x%04X\n",
- le16_to_cpu(status.magic), le16_to_cpu(status.code));
-#endif
- err = -EPROTO;
- if (status.magic != cpu_to_le16(UCMB_MAGIC))
- goto out_free;
- err = ucmb_status_code_to_errno(le16_to_cpu(status.code));
- if (err)
- goto out_free;
-
-out_free:
- free_page((unsigned long)buf);
-out:
- mutex_unlock(&ucmb->mutex);
-
- return err ? err : size;
-}
-
-static int __devinit ucmb_probe(struct platform_device *pdev)
-{
- struct ucmb_platform_data *pdata;
- struct ucmb *ucmb;
- int err;
- const int bus_num = ucmb_spi_busnum_count++;
- struct spi_bitbang *bb;
-
- pdata = pdev->dev.platform_data;
- if (!pdata)
- return -ENXIO;
-
- ucmb = kzalloc(sizeof(struct ucmb), GFP_KERNEL);
- if (!ucmb)
- return -ENOMEM;
- mutex_init(&ucmb->mutex);
- ucmb->gpio_reset = pdata->gpio_reset;
- ucmb->reset_activelow = pdata->reset_activelow;
- ucmb->chunk_size = pdata->chunk_size;
-
-#ifdef CONFIG_PREEMPT
- /* A preemptible kernel does not need to sleep between
- * chunks, because it can sleep at desire (if IRQs are enabled).
- * So transmit/receive it all in one go. */
- ucmb->chunk_size = 0;
-#endif
-
- /* Create the SPI GPIO bus master. */
-
-#ifdef CONFIG_SPI_GPIO_MODULE
- err = request_module("spi_gpio");
- if (err)
- printk(KERN_WARNING PFX "Failed to request spi_gpio module\n");
-#endif /* CONFIG_SPI_GPIO_MODULE */
-
- ucmb->spi_gpio_pdata.sck = pdata->gpio_sck;
- ucmb->spi_gpio_pdata.mosi = pdata->gpio_mosi;
- ucmb->spi_gpio_pdata.miso = pdata->gpio_miso;
- ucmb->spi_gpio_pdata.num_chipselect = 1;
-
- ucmb->spi_gpio_pdev.name = "spi_gpio";
- ucmb->spi_gpio_pdev.id = bus_num;
- ucmb->spi_gpio_pdev.dev.platform_data = &ucmb->spi_gpio_pdata;
-
- err = platform_device_register(&ucmb->spi_gpio_pdev);
- if (err) {
- printk(KERN_ERR PFX "Failed to register SPI-GPIO platform device\n");
- goto err_free_ucmb;
- }
- bb = platform_get_drvdata(&ucmb->spi_gpio_pdev);
- if (!bb || !bb->master) {
- printk(KERN_ERR PFX "No bitbanged master device found.\n");
- goto err_unreg_spi_gpio_pdev;
- }
-
- /* Create the SPI device. */
-
- ucmb->sdev = spi_alloc_device(bb->master);
- if (!ucmb->sdev) {
- printk(KERN_ERR PFX "Failed to allocate SPI device\n");
- goto err_unreg_spi_gpio_pdev;
- }
- ucmb->sdev->max_speed_hz = pdata->max_speed_hz;
- ucmb->sdev->chip_select = 0;
- ucmb->sdev->mode = pdata->mode;
- strlcpy(ucmb->sdev->modalias, "ucmb", /* We are the SPI driver. */
- sizeof(ucmb->sdev->modalias));
- ucmb->sdev->controller_data = (void *)pdata->gpio_cs;
- err = spi_add_device(ucmb->sdev);
- if (err) {
- printk(KERN_ERR PFX "Failed to add SPI device\n");
- goto err_free_spi_device;
- }
-
- /* Initialize the RESET line. */
-
- if (pdata->gpio_reset != UCMB_NO_RESET) {
- err = gpio_request(pdata->gpio_reset, pdata->name);
- if (err) {
- printk(KERN_ERR PFX
- "Failed to request RESET GPIO line\n");
- goto err_unreg_spi_device;
- }
- err = gpio_direction_output(pdata->gpio_reset,
- pdata->reset_activelow);
- if (err) {
- printk(KERN_ERR PFX
- "Failed to set RESET GPIO direction\n");
- goto err_free_reset_gpio;
- }
- ucmb_reset_microcontroller(ucmb);
- }
-
- /* Create the Misc char device. */
-
- ucmb->mdev.minor = MISC_DYNAMIC_MINOR;
- ucmb->mdev.name = pdata->name;
- ucmb->mdev.parent = &pdev->dev;
- ucmb->mdev_fops.open = ucmb_open;
- ucmb->mdev_fops.release = ucmb_release;
- ucmb->mdev_fops.read = ucmb_read;
- ucmb->mdev_fops.write = ucmb_write;
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,36)
- ucmb->mdev_fops.unlocked_ioctl = ucmb_ioctl;
-#else
- ucmb->mdev_fops.ioctl = ucmb_ioctl;
-#endif
- ucmb->mdev.fops = &ucmb->mdev_fops;
-
- err = misc_register(&ucmb->mdev);
- if (err) {
- printk(KERN_ERR PFX "Failed to register miscdev %s\n",
- ucmb->mdev.name);
- goto err_free_reset_gpio;
- }
-
- platform_set_drvdata(pdev, ucmb);
-
- printk(KERN_INFO PFX "Registered message bus \"%s\"\n", pdata->name);
-
- return 0;
-
-err_free_reset_gpio:
- if (pdata->gpio_reset != UCMB_NO_RESET)
- gpio_free(pdata->gpio_reset);
-err_unreg_spi_device:
- spi_unregister_device(ucmb->sdev);
-err_free_spi_device:
- spi_dev_put(ucmb->sdev);
-err_unreg_spi_gpio_pdev:
- platform_device_unregister(&ucmb->spi_gpio_pdev);
-err_free_ucmb:
- kfree(ucmb);
-
- return err;
-}
-
-static int __devexit ucmb_remove(struct platform_device *pdev)
-{
- struct ucmb *ucmb = platform_get_drvdata(pdev);
- int err;
-
- err = misc_deregister(&ucmb->mdev);
- if (err) {
- printk(KERN_ERR PFX "Failed to unregister miscdev %s\n",
- ucmb->mdev.name);
- }
- if (ucmb->gpio_reset != UCMB_NO_RESET)
- gpio_free(ucmb->gpio_reset);
- spi_unregister_device(ucmb->sdev);
- spi_dev_put(ucmb->sdev);
- platform_device_unregister(&ucmb->spi_gpio_pdev);
-
- kfree(ucmb);
- platform_set_drvdata(pdev, NULL);
-
- return 0;
-}
-
-static struct platform_driver ucmb_driver = {
- .driver = {
- .name = "ucmb",
- .owner = THIS_MODULE,
- },
- .probe = ucmb_probe,
- .remove = __devexit_p(ucmb_remove),
-};
-
-int ucmb_device_register(struct ucmb_platform_data *pdata)
-{
- struct platform_device *pdev;
- int err;
-
- pdev = platform_device_alloc("ucmb", ucmb_pdev_id_count++);
- if (!pdev) {
- printk(KERN_ERR PFX "Failed to allocate platform device.\n");
- return -ENOMEM;
- }
- err = platform_device_add_data(pdev, pdata, sizeof(*pdata));
- if (err) {
- printk(KERN_ERR PFX "Failed to add platform data.\n");
- platform_device_put(pdev);
- return err;
- }
- err = platform_device_add(pdev);
- if (err) {
- printk(KERN_ERR PFX "Failed to register platform device.\n");
- platform_device_put(pdev);
- return err;
- }
- pdata->pdev = pdev;
-
- return 0;
-}
-EXPORT_SYMBOL(ucmb_device_register);
-
-void ucmb_device_unregister(struct ucmb_platform_data *pdata)
-{
- if (!pdata->pdev)
- return;
- platform_device_unregister(pdata->pdev);
- platform_device_put(pdata->pdev);
- pdata->pdev = NULL;
-}
-EXPORT_SYMBOL(ucmb_device_unregister);
-
-static int ucmb_modinit(void)
-{
- int err;
-
- printk(KERN_INFO "Microcontroller message bus driver\n");
-
- err = spi_register_driver(&ucmb_spi_driver);
- if (err) {
- printk(KERN_ERR PFX "Failed to register SPI driver\n");
- return err;
- }
- err = platform_driver_register(&ucmb_driver);
- if (err) {
- printk(KERN_ERR PFX "Failed to register platform driver\n");
- spi_unregister_driver(&ucmb_spi_driver);
- return err;
- }
-
- return 0;
-}
-subsys_initcall(ucmb_modinit);
-
-static void ucmb_modexit(void)
-{
- platform_driver_unregister(&ucmb_driver);
- spi_unregister_driver(&ucmb_spi_driver);
-}
-module_exit(ucmb_modexit);
+++ /dev/null
-#ifndef LINUX_UCMB_H_
-#define LINUX_UCMB_H_
-
-#include <linux/types.h>
-#include <linux/ioctl.h>
-
-
-/* IOCTLs */
-#define __UCMB_IOCTL ('U'|'C'|'M'|'B')
-
-/** UCMB_IOCTL_RESETUC - Reset the microcontroller. */
-#define UCMB_IOCTL_RESETUC _IO(__UCMB_IOCTL, 0)
-/** UCMB_IOCTL_GMSGDELAY - Get the delay to wait before fetching the status. */
-#define UCMB_IOCTL_GMSGDELAY _IOR(__UCMB_IOCTL, 1, unsigned int)
-/** UCMB_IOCTL_SMSGDELAY - Set the delay to wait before fetching the status. */
-#define UCMB_IOCTL_SMSGDELAY _IOW(__UCMB_IOCTL, 2, unsigned int)
-
-
-#ifdef __KERNEL__
-
-#include <linux/device.h>
-#include <linux/spi/spi.h>
-#include <linux/spi/spi_gpio.h>
-
-/**
- * struct ucmb_platform_data - UCMB device descriptor
- *
- * @name: The name of the device. This will also be the name of
- * the misc char device.
- *
- * @gpio_cs: The chipselect GPIO pin. Can be SPI_GPIO_NO_CHIPSELECT,
- * if chipselect is not used.
- * @gpio_sck: The clock GPIO pin.
- * @gpio_miso: The master-in slave-out GPIO pin.
- * @gpio_mosi: The master-out slave-in GPIO pin.
- *
- * @gpio_reset: The GPIO pin to the microcontroller reset line.
- * Can be UCMB_NO_RESET, if reset GPIO is not used.
- * @reset_activelow: If true, @gpio_reset is considered to be active
- * on logical 0 (inverted).
- *
- * @mode: The SPI bus mode. SPI_MODE_*
- * @max_speed_hz: The bus speed, in Hz. If zero the speed is not limited.
- * @chunk_size: The maximum chunk size to transmit/receive in one go
- * without sleeping. The kernel will be allowed to sleep
- * after each chunk.
- * If set to 0, the whole data will be transmitted/received
- * in one big rush without sleeping. Note that this might hurt
- * system responsiveness, if the kernel is not preemptible.
- * If CONFIG_PREEMPT is enabled, chunk_size will be forced to 0.
- */
-struct ucmb_platform_data {
- const char *name;
-
- unsigned long gpio_cs;
- unsigned int gpio_sck;
- unsigned int gpio_miso;
- unsigned int gpio_mosi;
-
- unsigned int gpio_reset;
- bool reset_activelow;
-
- u8 mode;
- u32 max_speed_hz;
- unsigned int chunk_size;
-
- struct platform_device *pdev; /* internal */
-};
-
-#define UCMB_NO_RESET ((unsigned int)-1)
-
-int ucmb_device_register(struct ucmb_platform_data *pdata);
-void ucmb_device_unregister(struct ucmb_platform_data *pdata);
-
-
-#endif /* __KERNEL__ */
-#endif /* LINUX_UCMB_H_ */
+++ /dev/null
-/*
- * Microcontroller message bus
- * uc-side slave implementation for Atmel AVR8
- *
- * The gcc compiler always treats multi-byte variables as litte-endian.
- * So no explicit endianness conversions are done on the message header,
- * footer and status data structures.
- *
- * Copyright (C) 2009 Michael Buesch <mb@bu3sch.de>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-#include "ucmb.h"
-
-#include <stdint.h>
-#include <avr/io.h>
-#include <avr/interrupt.h>
-#include <util/crc16.h>
-
-
-struct ucmb_message_hdr {
- uint16_t magic; /* UCMB_MAGIC */
- uint16_t len; /* Payload length (excluding header and footer) */
-} __attribute__((packed));
-
-struct ucmb_message_footer {
- uint16_t crc; /* CRC of the header + payload. */
-} __attribute__((packed));
-
-struct ucmb_status {
- uint16_t magic; /* UCMB_MAGIC */
- uint16_t code; /* enum ucmb_status_code */
-} __attribute__((packed));
-
-#define UCMB_MAGIC 0x1337
-
-enum ucmb_status_code {
- UCMB_STAT_OK = 0,
- UCMB_STAT_EPROTO, /* Protocol format error */
- UCMB_STAT_ENOMEM, /* Out of memory */
- UCMB_STAT_E2BIG, /* Message too big */
- UCMB_STAT_ECRC, /* CRC error */
-};
-
-
-static uint8_t ucmb_buf[sizeof(struct ucmb_message_hdr) +
- UCMB_MAX_MSG_LEN +
- sizeof(struct ucmb_message_footer)];
-static uint16_t ucmb_buf_ptr;
-static struct ucmb_status status_buf;
-static uint16_t ucmb_send_message_len;
-
-/* Statemachine */
-static uint8_t ucmb_state;
-enum {
- UCMB_ST_LISTEN, /* Listen for incoming messages. */
- UCMB_ST_SENDSTATUS, /* Send the status report. */
- UCMB_ST_SENDMESSAGE, /* Send the message. */
- UCMB_ST_RETRSTATUS, /* Retrieve the status report. */
-};
-
-#define TRAILING 1
-
-
-static void ucmb_send_next_byte(void)
-{
- switch (ucmb_state) {
- case UCMB_ST_SENDSTATUS: {
- const uint8_t *st = (const uint8_t *)&status_buf;
-
- if (ucmb_buf_ptr < sizeof(struct ucmb_status))
- SPDR = st[ucmb_buf_ptr];
- ucmb_buf_ptr++;
- if (ucmb_buf_ptr == sizeof(struct ucmb_status) + TRAILING) {
- ucmb_buf_ptr = 0;
- if (ucmb_send_message_len) {
- ucmb_state = UCMB_ST_SENDMESSAGE;
- goto st_sendmessage;
- } else
- ucmb_state = UCMB_ST_LISTEN;
- }
- break;
- }
- case UCMB_ST_SENDMESSAGE: {
- st_sendmessage:;
- uint16_t full_length = sizeof(struct ucmb_message_hdr) +
- ucmb_send_message_len +
- sizeof(struct ucmb_message_footer);
- if (ucmb_buf_ptr < full_length)
- SPDR = ucmb_buf[ucmb_buf_ptr];
- ucmb_buf_ptr++;
- if (ucmb_buf_ptr == full_length + TRAILING) {
- ucmb_send_message_len = 0;
- ucmb_buf_ptr = 0;
- ucmb_state = UCMB_ST_RETRSTATUS;
- }
- break;
- } }
-}
-
-static uint16_t crc16_block_update(uint16_t crc, const void *_data, uint16_t size)
-{
- const uint8_t *data = _data;
-
- while (size) {
- crc = _crc16_update(crc, *data);
- data++;
- size--;
- }
-
- return crc;
-}
-
-static uint16_t ucmb_calc_msg_buffer_crc(void)
-{
- const struct ucmb_message_hdr *hdr;
- uint16_t crc = 0xFFFF;
-
- hdr = (const struct ucmb_message_hdr *)ucmb_buf;
- crc = crc16_block_update(crc, ucmb_buf,
- sizeof(struct ucmb_message_hdr) + hdr->len);
- crc ^= 0xFFFF;
-
- return crc;
-}
-
-/* SPI data transfer interrupt. */
-ISR(SPI_STC_vect)
-{
- uint8_t data;
-
- data = SPDR;
- SPDR = 0;
-
- switch (ucmb_state) {
- case UCMB_ST_LISTEN: {
- struct ucmb_message_hdr *hdr;
- struct ucmb_message_footer *footer;
-
- if (ucmb_buf_ptr < sizeof(ucmb_buf))
- ucmb_buf[ucmb_buf_ptr] = data;
- ucmb_buf_ptr++;
- if (ucmb_buf_ptr < sizeof(struct ucmb_message_hdr))
- return; /* Header RX not complete. */
- hdr = (struct ucmb_message_hdr *)ucmb_buf;
- if (ucmb_buf_ptr == sizeof(struct ucmb_message_hdr)) {
- if (hdr->magic != UCMB_MAGIC) {
- /* Invalid magic! Reset. */
- ucmb_buf_ptr = 0;
- return;
- }
- if (hdr->len > 0x8000) {
- /* Completely bogus length! Reset. */
- ucmb_buf_ptr = 0;
- return;
- }
- return;
- }
-
- if (ucmb_buf_ptr == sizeof(struct ucmb_message_hdr) +
- sizeof(struct ucmb_message_footer) +
- hdr->len) {
- status_buf.magic = UCMB_MAGIC;
- status_buf.code = UCMB_STAT_OK;
- if (ucmb_buf_ptr > sizeof(ucmb_buf)) {
- /* Message is way too big and was truncated. */
- status_buf.code = UCMB_STAT_E2BIG;
- } else {
- footer = (struct ucmb_message_footer *)(
- ucmb_buf + sizeof(struct ucmb_message_hdr) +
- hdr->len);
- if (ucmb_calc_msg_buffer_crc() != footer->crc)
- status_buf.code = UCMB_STAT_ECRC;
- }
- ucmb_state = UCMB_ST_SENDSTATUS;
- ucmb_buf_ptr = 0;
- ucmb_send_next_byte();
-
- if (status_buf.code != UCMB_STAT_OK)
- return; /* Corrupt message. Don't pass it to user code. */
-
- ucmb_send_message_len = ucmb_rx_message(
- ucmb_buf + sizeof(struct ucmb_message_hdr),
- hdr->len);
- if (ucmb_send_message_len) {
- footer = (struct ucmb_message_footer *)(
- ucmb_buf + sizeof(struct ucmb_message_hdr) +
- ucmb_send_message_len);
-
- hdr->magic = UCMB_MAGIC;
- hdr->len = ucmb_send_message_len;
- footer->crc = ucmb_calc_msg_buffer_crc();
- }
- }
- break;
- }
- case UCMB_ST_SENDSTATUS:
- case UCMB_ST_SENDMESSAGE:
- ucmb_send_next_byte();
- break;
- case UCMB_ST_RETRSTATUS: {
- uint8_t *st = (uint8_t *)&status_buf;
-
- st[ucmb_buf_ptr++] = data;
- if (ucmb_buf_ptr == sizeof(struct ucmb_status)) {
- /* We could possibly handle the status report here... */
- ucmb_buf_ptr = 0;
- ucmb_state = UCMB_ST_LISTEN;
- }
- break;
- } }
-}
-
-void ucmb_init(void)
-{
- ucmb_state = UCMB_ST_LISTEN;
-
- /* SPI slave mode 0 with IRQ enabled. */
- DDRB |= (1 << 4/*MISO*/);
- DDRB &= ~((1 << 5/*SCK*/) | (1 << 3/*MOSI*/) | (1 << 2/*SS*/));
- SPCR = (1 << SPE) | (1 << SPIE) /*| (1 << CPOL) | (1 << CPHA)*/;
- (void)SPSR; /* clear state */
- (void)SPDR; /* clear state */
-}
+++ /dev/null
-#ifndef UCMB_AVR8_H_
-#define UCMB_AVR8_H_
-
-#include <stdint.h>
-
-
-/* Max length of the message payload. */
-#define UCMB_MAX_MSG_LEN 0x200
-
-/* ucmb_rx_message - Message receive callback.
- * Define this elsewhere. It's called on successful retrieval
- * of a new message.
- * If a reply message has to be transferred after this one, put the
- * message payload into the "payload" buffer and return the number
- * of bytes to transmit. If no reply message is needed, return 0.
- * Note that the "payload" buffer always has a size of UCMB_MAX_MSG_LEN.
- */
-extern uint16_t ucmb_rx_message(uint8_t *payload,
- uint16_t payload_length);
-
-/* Initialize the UCMB subsystem. */
-void ucmb_init(void);
-
-#endif /* UCMB_AVR8_H_ */
+++ /dev/null
-/*
- * Microcontroller message bus
- * uc-side slave implementation for Atmel AVR8
- *
- * The gcc compiler always treats multi-byte variables as litte-endian.
- * So no explicit endianness conversions are done on the message header,
- * footer and status data structures.
- *
- * This hotpath-assembly implementation is about twice as fast
- * as the C implementation.
- *
- * Copyright (C) 2009 Michael Buesch <mb@bu3sch.de>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- */
-
-#include "ucmb.h"
-
-#include <stdint.h>
-#include <avr/io.h>
-#include <avr/interrupt.h>
-#include <avr/pgmspace.h>
-#include <avr/wdt.h>
-
-
-#ifndef __GNUC__
-# error "Need the GNU C compiler"
-#endif
-
-#undef __naked
-#define __naked __attribute__((__naked__))
-#undef __used
-#define __used __attribute__((__used__))
-#undef __noret
-#define __noret __attribute__((__noreturn__))
-#undef offsetof
-#define offsetof(type, member) ((size_t)&((type *)0)->member)
-#undef unlikely
-#define unlikely(x) __builtin_expect(!!(x), 0)
-#undef mb
-#define mb() __asm__ __volatile__("" : : : "memory") /* memory barrier */
-#ifndef ucmb_errorlog
-# define ucmb_errorlog(message) do { /* nothing */ } while (0)
-#endif
-
-
-struct ucmb_message_hdr {
- uint16_t magic; /* UCMB_MAGIC */
- uint16_t len; /* Payload length (excluding header and footer) */
-} __attribute__((packed));
-
-struct ucmb_message_footer {
- uint16_t crc; /* CRC of the header + payload. */
-} __attribute__((packed));
-
-struct ucmb_status {
- uint16_t magic; /* UCMB_MAGIC */
- uint16_t code; /* enum ucmb_status_code */
-} __attribute__((packed));
-
-#define UCMB_MAGIC 0x1337
-
-enum ucmb_status_code {
- UCMB_STAT_OK = 0,
- UCMB_STAT_EPROTO, /* Protocol format error */
- UCMB_STAT_ENOMEM, /* Out of memory */
- UCMB_STAT_E2BIG, /* Message too big */
- UCMB_STAT_ECRC, /* CRC error */
-};
-
-
-static uint8_t ucmb_buf[sizeof(struct ucmb_message_hdr) +
- UCMB_MAX_MSG_LEN +
- sizeof(struct ucmb_message_footer)] __used;
-static uint16_t ucmb_buf_ptr __used;
-static struct ucmb_status status_buf __used;
-static uint16_t ucmb_send_message_len __used;
-static uint8_t ucmb_received_message;
-
-/* The current IRQ handler */
-static void (*ucmb_interrupt_handler)(void) __used;
-
-
-/* Polynomial: x^16 + x^15 + x^2 + 1 */
-static const prog_uint16_t crc16_table[256] = {
- 0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
- 0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
- 0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
- 0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
- 0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
- 0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
- 0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
- 0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
- 0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
- 0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
- 0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
- 0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
- 0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
- 0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
- 0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
- 0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
- 0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
- 0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
- 0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
- 0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
- 0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
- 0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
- 0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
- 0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
- 0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
- 0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
- 0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
- 0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
- 0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
- 0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
- 0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
- 0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040
-};
-
-static inline uint16_t crc16_block_update(uint16_t crc, const void *_data, uint16_t size)
-{
- const uint8_t *data = _data;
- uint8_t offset;
-
- while (size--) {
- wdt_reset();
- offset = crc ^ *data;
- crc = (crc >> 8) ^ pgm_read_word(&crc16_table[offset]);
- data++;
- }
-
- return crc;
-}
-
-static inline uint16_t ucmb_calc_msg_buffer_crc(void)
-{
- const struct ucmb_message_hdr *hdr;
- uint16_t crc = 0xFFFF;
-
- hdr = (const struct ucmb_message_hdr *)ucmb_buf;
- crc = crc16_block_update(crc, ucmb_buf,
- sizeof(struct ucmb_message_hdr) + hdr->len);
- crc ^= 0xFFFF;
-
- return crc;
-}
-
-/* The generic interrupt handler.
- * This just branches to the state specific handler.
- */
-ISR(SPI_STC_vect) __naked;
-ISR(SPI_STC_vect)
-{
- __asm__ __volatile__(
-" ; UCMB generic interrupt handler \n"
-" push __tmp_reg__ \n"
-" in __tmp_reg__, __SREG__ \n"
-" push r30 \n"
-" push r31 \n"
-" lds r30, ucmb_interrupt_handler + 0 \n"
-" lds r31, ucmb_interrupt_handler + 1 \n"
-" ijmp ; Jump to the real handler \n"
- );
-}
-#define UCMB_IRQ_EPILOGUE \
-" ; UCMB interrupt epilogue (start) \n"\
-" pop r31 \n"\
-" pop r30 \n"\
-" out __SREG__, __tmp_reg__ \n"\
-" pop __tmp_reg__ \n"\
-" reti \n"\
-" ; UCMB interrupt epilogue (end) \n"
-
-static void __naked __used ucmb_handler_LISTEN(void)
-{
- __asm__ __volatile__(
-" push r16 \n"
-" push r17 \n"
-" push r18 \n"
-" lds r16, ucmb_buf_ptr + 0 \n"
-" lds r17, ucmb_buf_ptr + 1 \n"
-" ldi r18, hi8(%[sizeof_buf]) \n"
-" cpi r16, lo8(%[sizeof_buf]) \n"
-" cpc r17, r18 \n"
-" in r18, %[_SPDR] \n"
-" brsh 1f ; overflow \n"
-" ; Store SPDR in the buffer \n"
-" movw r30, r16 \n"
-" subi r30, lo8(-(ucmb_buf)) \n"
-" sbci r31, hi8(-(ucmb_buf)) \n"
-" st Z, r18 \n"
-"1: \n"
-" ; Increment the buffer pointer \n"
-" subi r16, lo8(-1) \n"
-" sbci r17, hi8(-1) \n"
-" sts ucmb_buf_ptr + 0, r16 \n"
-" sts ucmb_buf_ptr + 1, r17 \n"
-" cpi r17, 0 \n"
-" brne 1f \n"
-" cpi r16, %[sizeof_msg_hdr] \n"
-" breq hdr_sanity_check ; buf_ptr == hdrlen \n"
-" brlo st_listen_out ; buf_ptr < hdrlen \n"
-"1: \n"
-" ; Get payload length from header \n"
-" lds r30, (ucmb_buf + %[offsetof_hdr_len] + 0) \n"
-" lds r31, (ucmb_buf + %[offsetof_hdr_len] + 1) \n"
-" ; Add header and footer length to get full length \n"
-" subi r30, lo8(-(%[sizeof_msg_hdr] + %[sizeof_msg_footer])) \n"
-" sbci r31, hi8(-(%[sizeof_msg_hdr] + %[sizeof_msg_footer])) \n"
-" ; Check if we have the full packet \n"
-" cp r30, r16 \n"
-" cpc r31, r17 \n"
-" breq st_listen_have_full_packet \n"
-"st_listen_out: \n"
-" pop r18 \n"
-" pop r17 \n"
-" pop r16 \n"
-UCMB_IRQ_EPILOGUE /* reti */
-" \n"
-"hdr_sanity_check: \n"
-" lds r30, (ucmb_buf + %[offsetof_hdr_magic] + 0) \n"
-" lds r31, (ucmb_buf + %[offsetof_hdr_magic] + 1) \n"
-" ldi r18, hi8(%[_UCMB_MAGIC]) \n"
-" cpi r30, lo8(%[_UCMB_MAGIC]) \n"
-" cpc r31, r18 \n"
-" brne invalid_hdr_magic \n"
-" lds r30, (ucmb_buf + %[offsetof_hdr_len] + 0) \n"
-" lds r31, (ucmb_buf + %[offsetof_hdr_len] + 1) \n"
-" ldi r18, hi8(0x8001) \n"
-" cpi r30, lo8(0x8001) \n"
-" cpc r31, r18 \n"
-" brsh bogus_payload_len \n"
-" rjmp st_listen_out \n"
-" \n"
-"invalid_hdr_magic: \n"
-" ; Invalid magic number in the packet header. Reset. \n"
-"bogus_payload_len: \n"
-" ; Bogus payload length in packet header. Reset. \n"
-" clr r18 \n"
-" sts ucmb_buf_ptr + 0, r18 \n"
-" sts ucmb_buf_ptr + 1, r18 \n"
-" rjmp st_listen_out \n"
-" \n"
-"st_listen_have_full_packet: \n"
-" ; We have the full packet. Any SPI transfer is stopped \n"
-" ; while we are processing the packet, so this \n"
-" ; is a slowpath. \n"
-" ; Disable SPI and pass control to ucmb_work to \n"
-" ; handle the message. \n"
-" cbi %[_SPCR], %[_SPIE] \n"
-" ldi r18, 1 \n"
-" sts ucmb_received_message, r18 \n"
-" rjmp st_listen_out \n"
- : /* none */
- : [sizeof_buf] "i" (sizeof(ucmb_buf))
- , [sizeof_msg_hdr] "M" (sizeof(struct ucmb_message_hdr))
- , [sizeof_msg_footer] "M" (sizeof(struct ucmb_message_footer))
- , [offsetof_hdr_magic] "M" (offsetof(struct ucmb_message_hdr, magic))
- , [offsetof_hdr_len] "M" (offsetof(struct ucmb_message_hdr, len))
- , [_SPDR] "M" (_SFR_IO_ADDR(SPDR))
- , [_SPCR] "M" (_SFR_IO_ADDR(SPCR))
- , [_SPIE] "i" (SPIE)
- , [_UCMB_MAGIC] "i" (UCMB_MAGIC)
- : "memory"
- );
-}
-
-static void __naked __used ucmb_handler_SENDSTATUS(void)
-{
- __asm__ __volatile__(
-" push r16 \n"
-/*" push r17 \n" */
-" push r18 \n"
-" lds r16, ucmb_buf_ptr + 0 \n"
-" cpi r16, %[sizeof_ucmb_status] \n"
-" brsh 1f ; This is the trailing byte \n"
-" ; Write the next byte from status_buf to SPDR \n"
-" mov r30, r16 \n"
-" clr r31 \n"
-" subi r30, lo8(-(status_buf)) \n"
-" sbci r31, hi8(-(status_buf)) \n"
-" ld r18, Z \n"
-" out %[_SPDR], r18 \n"
-"1: \n"
-" subi r16, lo8(-1) \n"
-" sts ucmb_buf_ptr + 0, r16 \n"
-" cpi r16, (%[sizeof_ucmb_status] + 1) \n"
-" brne st_sendstatus_out \n"
-" ; Finished. Sent all status_buf bytes + trailing byte. \n"
-" clr r18 \n"
-" sts ucmb_buf_ptr + 0, r18 \n"
-" ; Switch back to listening state... \n"
-" ldi r18, lo8(gs(ucmb_handler_LISTEN)) \n"
-" sts ucmb_interrupt_handler + 0, r18 \n"
-" ldi r18, hi8(gs(ucmb_handler_LISTEN)) \n"
-" sts ucmb_interrupt_handler + 1, r18 \n"
-" ; ...if we have no pending transmission \n"
-" lds r30, ucmb_send_message_len + 0 \n"
-" lds r31, ucmb_send_message_len + 1 \n"
-" clr r18 \n"
-" cpi r30, 0 \n"
-" cpc r31, r18 \n"
-" breq st_sendstatus_out \n"
-" ; Switch status to SENDMESSAGE and send the first byte. \n"
-" ldi r18, lo8(gs(ucmb_handler_SENDMESSAGE)) \n"
-" sts ucmb_interrupt_handler + 0, r18 \n"
-" ldi r18, hi8(gs(ucmb_handler_SENDMESSAGE)) \n"
-" sts ucmb_interrupt_handler + 1, r18 \n"
-" ; Send the first byte \n"
-" lds r18, ucmb_buf + 0 \n"
-" out %[_SPDR], r18 \n"
-" ldi r18, 1 \n"
-" sts ucmb_buf_ptr + 0, r18 \n"
-"st_sendstatus_out: \n"
-" pop r18 \n"
-/*" pop r17 \n"*/
-" pop r16 \n"
-UCMB_IRQ_EPILOGUE /* reti */
- : /* none */
- : [sizeof_ucmb_status] "M" (sizeof(struct ucmb_status))
- , [_SPDR] "M" (_SFR_IO_ADDR(SPDR))
- : "memory"
- );
-}
-
-static void __naked __used ucmb_handler_SENDMESSAGE(void)
-{
- __asm__ __volatile__(
-" push r16 \n"
-" push r17 \n"
-" push r18 \n"
-" lds r16, ucmb_buf_ptr + 0 \n"
-" lds r17, ucmb_buf_ptr + 1 \n"
-" lds r30, ucmb_send_message_len + 0 \n"
-" lds r31, ucmb_send_message_len + 1 \n"
-" cp r16, r30 \n"
-" cpc r17, r31 \n"
-" brsh 1f ; This is the trailing byte \n"
-" movw r30, r16 \n"
-" subi r30, lo8(-(ucmb_buf)) \n"
-" sbci r31, hi8(-(ucmb_buf)) \n"
-" ld r18, Z \n"
-" out %[_SPDR], r18 \n"
-"1: \n"
-" subi r16, lo8(-1) \n"
-" sbci r17, hi8(-1) \n"
-" sts ucmb_buf_ptr + 0, r16 \n"
-" sts ucmb_buf_ptr + 1, r17 \n"
-" lds r30, ucmb_send_message_len + 0 \n"
-" lds r31, ucmb_send_message_len + 1 \n"
-" subi r30, lo8(-1) \n"
-" sbci r31, hi8(-1) \n"
-" cp r16, r30 \n"
-" cpc r17, r31 \n"
-" brne st_sendmessage_out \n"
-" ; Message + trailing byte processed. Retrieve status. \n"
-" clr r18 \n"
-" sts ucmb_buf_ptr + 0, r18 \n"
-" sts ucmb_buf_ptr + 1, r18 \n"
-" ldi r18, lo8(gs(ucmb_handler_RETRSTATUS)) \n"
-" sts ucmb_interrupt_handler + 0, r18 \n"
-" ldi r18, hi8(gs(ucmb_handler_RETRSTATUS)) \n"
-" sts ucmb_interrupt_handler + 1, r18 \n"
-"st_sendmessage_out: \n"
-" pop r18 \n"
-" pop r17 \n"
-" pop r16 \n"
-UCMB_IRQ_EPILOGUE /* reti */
- : /* none */
- : [_SPDR] "M" (_SFR_IO_ADDR(SPDR))
- : "memory"
- );
-}
-
-static void __naked __used ucmb_handler_RETRSTATUS(void)
-{
- __asm__ __volatile__(
-" push r16 \n"
-/*" push r17 \n"*/
-" push r18 \n"
-" in r18, %[_SPDR] \n"
-" lds r16, ucmb_buf_ptr + 0 \n"
-" mov r30, r16 \n"
-" clr r31 \n"
-" subi r30, lo8(-(status_buf)) \n"
-" sbci r31, hi8(-(status_buf)) \n"
-" st Z, r18 \n"
-" subi r16, -1 \n"
-" sts ucmb_buf_ptr + 0, r16 \n"
-" cpi r16, %[sizeof_ucmb_status] \n"
-" brne st_retrstatus_out \n"
-" ; Completely received the status \n"
-" clr r16 \n"
-" sts ucmb_buf_ptr + 0, r16 \n"
-" ; Switch back to listening state... \n"
-" ldi r18, lo8(gs(ucmb_handler_LISTEN)) \n"
-" sts ucmb_interrupt_handler + 0, r18 \n"
-" ldi r18, hi8(gs(ucmb_handler_LISTEN)) \n"
-" sts ucmb_interrupt_handler + 1, r18 \n"
-" ; Check status-report magic value \n"
-" lds r30, (status_buf + %[offsetof_status_magic] + 0) \n"
-" lds r31, (status_buf + %[offsetof_status_magic] + 1) \n"
-" ldi r18, hi8(%[_UCMB_MAGIC]) \n"
-" cpi r30, lo8(%[_UCMB_MAGIC]) \n"
-" cpc r31, r18 \n"
-" brne invalid_status_magic \n"
-" ; Check status-report error code \n"
-" lds r30, (status_buf + %[offsetof_status_code] + 0) \n"
-" lds r31, (status_buf + %[offsetof_status_code] + 1) \n"
-" ldi r18, hi8(%[_UCMB_STAT_OK]) \n"
-" cpi r30, lo8(%[_UCMB_STAT_OK]) \n"
-" cpc r31, r18 \n"
-" brne faulty_status_code \n"
-"st_retrstatus_out: \n"
-" pop r18 \n"
-/*" pop r17 \n"*/
-" pop r16 \n"
-UCMB_IRQ_EPILOGUE /* reti */
-" \n"
-"invalid_status_magic: \n"
-"faulty_status_code: \n"
-" ; Branch to the C error handler \n"
-" ; The handler does not return, so we don't need to \n"
-" ; push/pop the registers. \n"
-" clr __zero_reg__ \n"
-" rjmp ucmb_received_faulty_status \n"
- : /* none */
- : [sizeof_ucmb_status] "M" (sizeof(struct ucmb_status))
- , [offsetof_status_magic] "M" (offsetof(struct ucmb_status, magic))
- , [offsetof_status_code] "M" (offsetof(struct ucmb_status, code))
- , [_SPDR] "M" (_SFR_IO_ADDR(SPDR))
- , [_UCMB_MAGIC] "i" (UCMB_MAGIC)
- , [_UCMB_STAT_OK] "i" (UCMB_STAT_OK)
- : "memory"
- );
-}
-
-/* We received a status report with an error condition.
- * This is called from assembly code. The function does not return. */
-static void __used __noret ucmb_received_faulty_status(void)
-{
- /* The master sent us a status report with an error code.
- * Something's wrong with us. Print a status message and
- * get caught by the watchdog, yummy.
- */
-
- cli();
- wdt_disable();
- wdt_enable(WDTO_15MS);
- ucmb_errorlog("UCMB: Received faulty status report. Triggering reset.");
- while (1) {
- /* "It's Coming Right For Us!" */
- }
-}
-
-void ucmb_work(void)
-{
- struct ucmb_message_hdr *hdr;
- struct ucmb_message_footer *footer;
- uint16_t payload_len;
-
- if (!ucmb_received_message)
- return;
-
- hdr = (struct ucmb_message_hdr *)ucmb_buf;
- payload_len = hdr->len;
-
- status_buf.magic = UCMB_MAGIC;
- status_buf.code = UCMB_STAT_OK;
- if (unlikely(ucmb_buf_ptr > sizeof(ucmb_buf))) {
- /* Message is way too big and was truncated. */
- status_buf.code = UCMB_STAT_E2BIG;
- } else {
- footer = (struct ucmb_message_footer *)(
- ucmb_buf + sizeof(struct ucmb_message_hdr) +
- payload_len);
- if (ucmb_calc_msg_buffer_crc() != footer->crc)
- status_buf.code = UCMB_STAT_ECRC;
- }
- ucmb_interrupt_handler = ucmb_handler_SENDSTATUS;
- ucmb_buf_ptr = 0;
- /* Send the first byte */
- SPDR = ((uint8_t *)&status_buf)[ucmb_buf_ptr];
- ucmb_buf_ptr++;
-
- if (unlikely(status_buf.code != UCMB_STAT_OK))
- goto out; /* Corrupt message. Don't pass it to user code. */
-
- ucmb_send_message_len = ucmb_rx_message(
- ucmb_buf + sizeof(struct ucmb_message_hdr),
- payload_len);
- if (ucmb_send_message_len) {
- footer = (struct ucmb_message_footer *)(
- ucmb_buf + sizeof(struct ucmb_message_hdr) +
- ucmb_send_message_len);
-
- hdr->magic = UCMB_MAGIC;
- hdr->len = ucmb_send_message_len;
- footer->crc = ucmb_calc_msg_buffer_crc();
-
- ucmb_send_message_len += sizeof(struct ucmb_message_hdr) +
- sizeof(struct ucmb_message_footer);
- }
-
-out:
- ucmb_received_message = 0;
- mb();
- /* Re-enable SPI */
- SPCR |= (1 << SPIE);
-}
-
-void ucmb_init(void)
-{
- ucmb_interrupt_handler = ucmb_handler_LISTEN;
-
- /* SPI slave mode 0 with IRQ enabled. */
- DDRB |= (1 << 6/*MISO*/);
- DDRB &= ~((1 << 7/*SCK*/) | (1 << 5/*MOSI*/) | (1 << 4/*SS*/));
- SPCR = (1 << SPE) | (1 << SPIE) /*| (1 << CPOL) | (1 << CPHA)*/;
- (void)SPSR; /* clear state */
- (void)SPDR; /* clear state */
-}
+++ /dev/null
-#ifndef UCMB_AVR8_H_
-#define UCMB_AVR8_H_
-
-#include <stdint.h>
-
-
-/* Max length of the message payload. */
-#define UCMB_MAX_MSG_LEN (128 * 64 / 8 + 16)
-
-/* Error logs: If you want UCMB error log messages, define
- * ucmb_errorlog(message_string_literal)
- * somewhere. If you don't define it, UCMB will be compiled
- * without error messages. */
-
-/* ucmb_rx_message - Message receive callback.
- * Define this elsewhere. It's called on successful retrieval
- * of a new message.
- * If a reply message has to be transferred after this one, put the
- * message payload into the "payload" buffer and return the number
- * of bytes to transmit. If no reply message is needed, return 0.
- * Note that the "payload" buffer always has a size of UCMB_MAX_MSG_LEN.
- * This function is called with interrupts enabled.
- */
-extern uint16_t ucmb_rx_message(uint8_t *payload,
- uint16_t payload_length);
-
-/* ucmb_work - Frequently call this from the mainloop.
- * Must not be called from interrupt context.
- * Must not be called with interrupts disabled.
- */
-void ucmb_work(void);
-
-/* Initialize the UCMB subsystem. */
-void ucmb_init(void);
-
-#endif /* UCMB_AVR8_H_ */
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