From a42be52bbf2b3a549d4b9635a5a93215dacd0657 Mon Sep 17 00:00:00 2001 From: Alexander Krutwig Date: Mon, 12 Sep 2016 15:00:46 +0200 Subject: Add SPI bus framework User API is compatible to Linux userspace API. New test libtests/spi01. Update #2776. --- cpukit/dev/spi/spi-bus.c | 366 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 366 insertions(+) create mode 100644 cpukit/dev/spi/spi-bus.c (limited to 'cpukit/dev/spi') 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 + * + * + * 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 + +#include + +#include +#include + +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; +} -- cgit v1.2.3