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-rw-r--r--cpukit/dev/i2c/i2c-dev.c291
1 files changed, 291 insertions, 0 deletions
diff --git a/cpukit/dev/i2c/i2c-dev.c b/cpukit/dev/i2c/i2c-dev.c
new file mode 100644
index 0000000000..b03effd1df
--- /dev/null
+++ b/cpukit/dev/i2c/i2c-dev.c
@@ -0,0 +1,291 @@
+/**
+ * @file
+ *
+ * @brief Inter-Integrated Circuit (I2C) Bus Implementation
+ *
+ * @ingroup I2CDevice
+ */
+
+/*
+ * Copyright (c) 2014 embedded brains GmbH. All rights reserved.
+ *
+ * embedded brains GmbH
+ * Dornierstr. 4
+ * 82178 Puchheim
+ * Germany
+ * <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE.
+ */
+
+#if HAVE_CONFIG_H
+ #include "config.h"
+#endif
+
+#include <dev/i2c/i2c.h>
+
+#include <rtems/imfs.h>
+#include <rtems/score/assert.h>
+
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static ssize_t i2c_dev_read(
+ rtems_libio_t *iop,
+ void *buffer,
+ size_t count
+)
+{
+ i2c_dev *dev = IMFS_generic_get_context_by_iop(iop);
+ ssize_t n;
+
+ n = (*dev->read)(dev, buffer, count, iop->offset);
+ if (n > 0) {
+ iop->offset += n;
+ }
+
+ return n;
+}
+
+static ssize_t i2c_dev_write(
+ rtems_libio_t *iop,
+ const void *buffer,
+ size_t count
+)
+{
+ i2c_dev *dev = IMFS_generic_get_context_by_iop(iop);
+ ssize_t n;
+
+ n = (*dev->write)(dev, buffer, count, iop->offset);
+ if (n > 0) {
+ iop->offset += n;
+ }
+
+ return n;
+}
+
+static int i2c_dev_ioctl(
+ rtems_libio_t *iop,
+ ioctl_command_t command,
+ void *arg
+)
+{
+ i2c_dev *dev = IMFS_generic_get_context_by_iop(iop);
+ int err;
+
+ err = (*dev->ioctl)(dev, command, arg);
+
+ if (err == 0) {
+ return 0;
+ } else {
+ rtems_set_errno_and_return_minus_one(-err);
+ }
+}
+
+static int i2c_dev_fstat(
+ const rtems_filesystem_location_info_t *loc,
+ struct stat *buf
+)
+{
+ i2c_dev *dev = IMFS_generic_get_context_by_location(loc);
+
+ buf->st_size = (*dev->get_size)(dev);
+ buf->st_blksize = (*dev->get_block_size)(dev);
+
+ return IMFS_stat(loc, buf);
+}
+
+static const rtems_filesystem_file_handlers_r i2c_dev_handler = {
+ .open_h = rtems_filesystem_default_open,
+ .close_h = rtems_filesystem_default_close,
+ .read_h = i2c_dev_read,
+ .write_h = i2c_dev_write,
+ .ioctl_h = i2c_dev_ioctl,
+ .lseek_h = rtems_filesystem_default_lseek_file,
+ .fstat_h = i2c_dev_fstat,
+ .ftruncate_h = rtems_filesystem_default_ftruncate,
+ .fsync_h = rtems_filesystem_default_fsync_or_fdatasync,
+ .fdatasync_h = rtems_filesystem_default_fsync_or_fdatasync,
+ .fcntl_h = rtems_filesystem_default_fcntl,
+ .kqfilter_h = rtems_filesystem_default_kqfilter,
+ .poll_h = rtems_filesystem_default_poll,
+ .readv_h = rtems_filesystem_default_readv,
+ .writev_h = rtems_filesystem_default_writev
+};
+
+static IMFS_jnode_t *i2c_dev_node_destroy(IMFS_jnode_t *node)
+{
+ i2c_dev *dev;
+
+ dev = IMFS_generic_get_context_by_node(node);
+ (*dev->destroy)(dev);
+
+ return node;
+}
+
+static const IMFS_node_control i2c_dev_node_control = {
+ .imfs_type = IMFS_GENERIC,
+ .handlers = &i2c_dev_handler,
+ .node_initialize = IMFS_node_initialize_generic,
+ .node_remove = IMFS_node_remove_default,
+ .node_destroy = i2c_dev_node_destroy
+};
+
+int i2c_dev_register(
+ i2c_dev *dev,
+ const char *dev_path
+)
+{
+ int rv;
+
+ rv = IMFS_make_generic_node(
+ dev_path,
+ S_IFCHR | S_IRWXU | S_IRWXG | S_IRWXO,
+ &i2c_dev_node_control,
+ dev
+ );
+ if (rv != 0) {
+ (*dev->destroy)(dev);
+ }
+
+ return rv;
+}
+
+static ssize_t i2c_dev_read_default(
+ i2c_dev *dev,
+ void *buf,
+ size_t n,
+ off_t offset
+)
+{
+ (void) dev;
+ (void) buf;
+ (void) n;
+ (void) offset;
+
+ return -EIO;
+}
+
+static ssize_t i2c_dev_write_default(
+ i2c_dev *dev,
+ const void *buf,
+ size_t n,
+ off_t offset
+)
+{
+ (void) dev;
+ (void) buf;
+ (void) n;
+ (void) offset;
+
+ return -EIO;
+}
+
+static int i2c_dev_ioctl_default(
+ i2c_dev *dev,
+ ioctl_command_t command,
+ void *arg
+)
+{
+ (void) dev;
+ (void) command;
+ (void) arg;
+
+ return -ENOTTY;
+}
+
+static off_t i2c_dev_get_size_default(i2c_dev *dev)
+{
+ (void) dev;
+
+ return 0;
+}
+
+static blksize_t i2c_dev_get_block_size_default(i2c_dev *dev)
+{
+ (void) dev;
+
+ return 1;
+}
+
+static int i2c_dev_do_init(
+ i2c_dev *dev,
+ const char *bus_path,
+ uint16_t address,
+ void (*destroy)(i2c_dev *dev)
+)
+{
+ int fd;
+ int rv;
+
+ fd = open(bus_path, O_RDWR);
+ if (fd < 0) {
+ (*destroy)(dev);
+
+ return -1;
+ }
+
+ rv = ioctl(fd, I2C_BUS_GET_CONTROL, &dev->bus);
+ if (rv != 0) {
+ (*destroy)(dev);
+
+ return -1;
+ }
+
+ dev->read = i2c_dev_read_default;
+ dev->write = i2c_dev_write_default;
+ dev->ioctl = i2c_dev_ioctl_default;
+ dev->get_size = i2c_dev_get_size_default;
+ dev->get_block_size = i2c_dev_get_block_size_default;
+ dev->destroy = destroy;
+ dev->bus_fd = fd;
+ dev->address = address;
+
+ return 0;
+}
+
+void i2c_dev_destroy(i2c_dev *dev)
+{
+ int rv;
+
+ rv = close(dev->bus_fd);
+ _Assert(rv == 0);
+ (void) rv;
+}
+
+void i2c_dev_destroy_and_free(i2c_dev *dev)
+{
+ i2c_dev_destroy(dev);
+ free(dev);
+}
+
+int i2c_dev_init(i2c_dev *dev, const char *bus_path, uint16_t address)
+{
+ return i2c_dev_do_init(dev, bus_path, address, i2c_dev_destroy);
+}
+
+i2c_dev *i2c_dev_alloc_and_init(
+ size_t size,
+ const char *bus_path,
+ uint16_t address
+)
+{
+ i2c_dev *dev = NULL;
+
+ if (size >= sizeof(*dev)) {
+ dev = calloc(1, size);
+ if (dev != NULL) {
+ int rv;
+
+ rv = i2c_dev_do_init(dev, bus_path, address, i2c_dev_destroy_and_free);
+ if (rv != 0) {
+ return NULL;
+ }
+ }
+ }
+
+ return dev;
+}