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authorAlexander Krutwig <alexander.krutwig@embedded-brains.de>2016-09-12 15:00:46 +0200
committerSebastian Huber <sebastian.huber@embedded-brains.de>2016-09-16 09:36:44 +0200
commita42be52bbf2b3a549d4b9635a5a93215dacd0657 (patch)
treedceb05cd4904c65302760edf853590d5282ca3e0 /cpukit/dev/spi
parentbsp/atsam: Use normal memory for QSPI flash area (diff)
downloadrtems-a42be52bbf2b3a549d4b9635a5a93215dacd0657.tar.bz2
Add SPI bus framework
User API is compatible to Linux userspace API. New test libtests/spi01. Update #2776.
Diffstat (limited to '')
-rw-r--r--cpukit/dev/spi/spi-bus.c366
1 files changed, 366 insertions, 0 deletions
diff --git a/cpukit/dev/spi/spi-bus.c b/cpukit/dev/spi/spi-bus.c
new file mode 100644
index 0000000000..dd84b021b2
--- /dev/null
+++ b/cpukit/dev/spi/spi-bus.c
@@ -0,0 +1,366 @@
+/**
+ * @file
+ *
+ * @brief Serial Peripheral Interface (SPI) Bus Implementation
+ *
+ * @ingroup SPIBus
+ */
+
+/*
+ * Copyright (c) 2016 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/spi/spi.h>
+
+#include <rtems/imfs.h>
+
+#include <stdlib.h>
+#include <string.h>
+
+static void spi_bus_obtain(spi_bus *bus)
+{
+ rtems_status_code sc;
+
+ sc = rtems_semaphore_obtain(bus->mutex, RTEMS_WAIT, RTEMS_NO_TIMEOUT);
+ _Assert(sc == RTEMS_SUCCESSFUL);
+ (void) sc;
+}
+
+static void spi_bus_release(spi_bus *bus)
+{
+ rtems_status_code sc;
+
+ sc = rtems_semaphore_release(bus->mutex);
+ _Assert(sc == RTEMS_SUCCESSFUL);
+ (void) sc;
+}
+
+static void spi_bus_set_defaults(spi_bus *bus, spi_ioc_transfer *msg)
+{
+ msg->cs_change = bus->cs_change;
+ msg->cs = bus->cs;
+ msg->bits_per_word = bus->bits_per_word;
+ msg->mode = bus->mode;
+ msg->speed_hz = bus->speed_hz;
+ msg->delay_usecs = bus->delay_usecs;
+}
+
+static ssize_t spi_bus_read(
+ rtems_libio_t *iop,
+ void *buffer,
+ size_t count
+)
+{
+ spi_bus *bus = IMFS_generic_get_context_by_iop(iop);
+ spi_ioc_transfer msg = {
+ .len = count,
+ .rx_buf = buffer
+ };
+ int err;
+
+ spi_bus_obtain(bus);
+ spi_bus_set_defaults(bus, &msg);
+ err = (*bus->transfer)(bus, &msg, 1);
+ spi_bus_release(bus);
+
+ if (err == 0) {
+ return msg.len;
+ } else {
+ rtems_set_errno_and_return_minus_one(-err);
+ }
+}
+
+static ssize_t spi_bus_write(
+ rtems_libio_t *iop,
+ const void *buffer,
+ size_t count
+)
+{
+ spi_bus *bus = IMFS_generic_get_context_by_iop(iop);
+ spi_ioc_transfer msg = {
+ .len = (uint16_t) count,
+ .tx_buf = buffer
+ };
+ int err;
+
+ spi_bus_obtain(bus);
+ spi_bus_set_defaults(bus, &msg);
+ err = (*bus->transfer)(bus, &msg, 1);
+ spi_bus_release(bus);
+
+ if (err == 0) {
+ return msg.len;
+ } else {
+ rtems_set_errno_and_return_minus_one(-err);
+ }
+}
+
+static int spi_bus_ioctl(
+ rtems_libio_t *iop,
+ ioctl_command_t command,
+ void *arg
+)
+{
+ spi_bus *bus = IMFS_generic_get_context_by_iop(iop);
+ int err;
+ uint32_t previous;
+
+ spi_bus_obtain(bus);
+
+ switch (command) {
+ case SPI_BUS_OBTAIN:
+ spi_bus_obtain(bus);
+ err = 0;
+ break;
+ case SPI_BUS_RELEASE:
+ spi_bus_release(bus);
+ err = 0;
+ break;
+ case SPI_IOC_RD_MODE:
+ *(uint8_t *) arg = bus->mode;
+ err = 0;
+ break;
+ case SPI_IOC_RD_MODE32:
+ *(uint32_t *) arg = bus->mode;
+ err = 0;
+ break;
+ case SPI_IOC_RD_LSB_FIRST:
+ *(uint8_t *) arg = bus->lsb_first;
+ err = 0;
+ break;
+ case SPI_IOC_RD_BITS_PER_WORD:
+ *(uint8_t *) arg = bus->bits_per_word;
+ err = 0;
+ break;
+ case SPI_IOC_RD_MAX_SPEED_HZ:
+ *(uint32_t *) arg = bus->speed_hz;
+ err = 0;
+ break;
+ case SPI_IOC_WR_MODE:
+ previous = bus->mode;
+ bus->mode = *(uint8_t *) arg;
+ err = (*bus->setup)(bus);
+
+ if (err != 0) {
+ bus->mode = previous;
+ }
+
+ break;
+ case SPI_IOC_WR_MODE32:
+ previous = bus->mode;
+ bus->mode = *(uint32_t *) arg;
+ err = (*bus->setup)(bus);
+
+ if (err != 0) {
+ bus->mode = previous;
+ }
+
+ break;
+ case SPI_IOC_WR_LSB_FIRST:
+ previous = bus->lsb_first;
+ bus->lsb_first = (*(uint8_t *) arg) != 0;
+ err = (*bus->setup)(bus);
+
+ if (err != 0) {
+ bus->lsb_first = (bool) previous;
+ }
+
+ break;
+ case SPI_IOC_WR_BITS_PER_WORD:
+ previous = bus->bits_per_word;
+ bus->bits_per_word = *(uint8_t *) arg;
+ err = (*bus->setup)(bus);
+
+ if (err != 0) {
+ bus->bits_per_word = (uint8_t) previous;
+ }
+
+ break;
+ case SPI_IOC_WR_MAX_SPEED_HZ:
+ previous = bus->speed_hz;
+ bus->speed_hz = *(uint32_t *) arg;
+ err = (*bus->setup)(bus);
+
+ if (err != 0) {
+ bus->speed_hz = previous;
+ }
+
+ break;
+ default:
+ if (IOCBASECMD(command) == IOCBASECMD(_IOW(SPI_IOC_MAGIC, 0, 0))) {
+ err = (*bus->transfer)(
+ bus,
+ arg,
+ IOCPARM_LEN(command) / sizeof(struct spi_ioc_transfer)
+ );
+ } else {
+ err = -EINVAL;
+ }
+ break;
+ }
+
+ spi_bus_release(bus);
+
+ if (err == 0) {
+ return 0;
+ } else {
+ rtems_set_errno_and_return_minus_one(-err);
+ }
+}
+
+static const rtems_filesystem_file_handlers_r spi_bus_handler = {
+ .open_h = rtems_filesystem_default_open,
+ .close_h = rtems_filesystem_default_close,
+ .read_h = spi_bus_read,
+ .write_h = spi_bus_write,
+ .ioctl_h = spi_bus_ioctl,
+ .lseek_h = rtems_filesystem_default_lseek,
+ .fstat_h = IMFS_stat,
+ .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 void spi_bus_node_destroy(IMFS_jnode_t *node)
+{
+ spi_bus *bus;
+
+ bus = IMFS_generic_get_context_by_node(node);
+ (*bus->destroy)(bus);
+
+ IMFS_node_destroy_default(node);
+}
+
+static const IMFS_node_control spi_bus_node_control = IMFS_GENERIC_INITIALIZER(
+ &spi_bus_handler,
+ IMFS_node_initialize_generic,
+ spi_bus_node_destroy
+);
+
+int spi_bus_register(
+ spi_bus *bus,
+ const char *bus_path
+)
+{
+ int rv;
+
+ rv = IMFS_make_generic_node(
+ bus_path,
+ S_IFCHR | S_IRWXU | S_IRWXG | S_IRWXO,
+ &spi_bus_node_control,
+ bus
+ );
+ if (rv != 0) {
+ (*bus->destroy)(bus);
+ }
+
+ return rv;
+}
+
+static int spi_bus_transfer_default(
+ spi_bus *bus,
+ const spi_ioc_transfer *msgs,
+ uint32_t msg_count
+)
+{
+ (void) bus;
+ (void) msgs;
+ (void) msg_count;
+
+ return -EIO;
+}
+
+static int spi_bus_setup_default(
+ spi_bus *bus
+)
+{
+ (void) bus;
+
+ return -EIO;
+}
+
+static int spi_bus_do_init(
+ spi_bus *bus,
+ void (*destroy)(spi_bus *bus)
+)
+{
+ rtems_status_code sc;
+
+ sc = rtems_semaphore_create(
+ rtems_build_name('S', 'P', 'I', ' '),
+ 1,
+ RTEMS_BINARY_SEMAPHORE | RTEMS_INHERIT_PRIORITY | RTEMS_PRIORITY,
+ 0,
+ &bus->mutex
+ );
+ if (sc != RTEMS_SUCCESSFUL) {
+ (*destroy)(bus);
+ rtems_set_errno_and_return_minus_one(ENOMEM);
+ }
+
+ bus->transfer = spi_bus_transfer_default;
+ bus->setup = spi_bus_setup_default;
+ bus->destroy = destroy;
+ bus->bits_per_word = 8;
+ return 0;
+}
+
+void spi_bus_destroy(spi_bus *bus)
+{
+ rtems_status_code sc;
+
+ sc = rtems_semaphore_delete(bus->mutex);
+ _Assert(sc == RTEMS_SUCCESSFUL);
+ (void) sc;
+}
+
+void spi_bus_destroy_and_free(spi_bus *bus)
+{
+ spi_bus_destroy(bus);
+ free(bus);
+}
+
+int spi_bus_init(spi_bus *bus)
+{
+ memset(bus, 0, sizeof(*bus));
+
+ return spi_bus_do_init(bus, spi_bus_destroy);
+}
+
+spi_bus *spi_bus_alloc_and_init(size_t size)
+{
+ spi_bus *bus = NULL;
+
+ if (size >= sizeof(*bus)) {
+ bus = calloc(1, size);
+ if (bus != NULL) {
+ int rv;
+
+ rv = spi_bus_do_init(bus, spi_bus_destroy_and_free);
+ if (rv != 0) {
+ return NULL;
+ }
+ }
+ }
+
+ return bus;
+}