bsp/altera-cyclone-v: Add a simple I2C driver.

1 files changed, 215 insertions, 0 deletions

diff --git a/c/src/lib/libbsp/arm/altera-cyclone-v/i2c/i2cdrv.c b/c/src/lib/libbsp/arm/altera-cyclone-v/i2c/i2cdrv.c
new file mode 100644
index 0000000000..3ea23551d8
--- /dev/null
+++ b/c/src/lib/libbsp/arm/altera-cyclone-v/i2c/i2cdrv.c
@@ -0,0 +1,215 @@
+/*
+ * Copyright (c) 2014 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Dornierstr. 4
+ *  82178 Puchheim
+ *  Germany
+ *  <info@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.
+ */
+
+#include <bsp.h>
+#include <bsp/i2cdrv.h>
+#include <assert.h>
+#include <rtems/libio.h>
+#include "i2cdrv-config.h"
+
+typedef struct {
+  ALT_I2C_DEV_t i2c_dev;
+  rtems_id mutex;
+} i2cdrv_entry;
+
+i2cdrv_entry i2cdrv_table[CYCLONE_V_NO_I2C];
+
+static ALT_I2C_DEV_t *get_device(i2cdrv_entry *e)
+{
+  return &e->i2c_dev;
+}
+
+static rtems_status_code init_i2c_module(
+  i2cdrv_entry *e,
+  const i2cdrv_configuration *cfg
+)
+{
+  ALT_STATUS_CODE asc = ALT_E_SUCCESS;
+  ALT_I2C_CTLR_t controller = cfg->controller;
+  ALT_I2C_DEV_t *dev = get_device(e);
+  ALT_I2C_MASTER_CONFIG_t i2c_cfg = {
+    .addr_mode = ALT_I2C_ADDR_MODE_7_BIT,
+    .restart_enable = false,
+  };
+
+  asc = alt_i2c_init(controller, dev);
+  if ( asc != ALT_E_SUCCESS ) {
+    return RTEMS_IO_ERROR;
+  }
+  asc = alt_i2c_op_mode_set(dev, ALT_I2C_MODE_MASTER);
+  if ( asc != ALT_E_SUCCESS ) {
+    return RTEMS_IO_ERROR;
+  }
+  asc = alt_i2c_master_config_speed_set(dev, &i2c_cfg, cfg->speed);
+  if ( asc != ALT_E_SUCCESS ) {
+    return RTEMS_IO_ERROR;
+  }
+  asc = alt_i2c_master_config_set(dev, &i2c_cfg);
+  if ( asc != ALT_E_SUCCESS ) {
+    return RTEMS_IO_ERROR;
+  }
+  asc = alt_i2c_enable(dev);
+  if ( asc != ALT_E_SUCCESS ) {
+    return RTEMS_IO_ERROR;
+  }
+
+  return RTEMS_SUCCESSFUL;
+}
+
+rtems_device_driver i2cdrv_initialize(
+  rtems_device_major_number major,
+  rtems_device_minor_number minor,
+  void *arg
+)
+{
+  rtems_status_code sc = RTEMS_SUCCESSFUL;
+
+  for ( size_t i = 0; i < CYCLONE_V_NO_I2C; ++i ) {
+    i2cdrv_entry *e = &i2cdrv_table[i];
+    const i2cdrv_configuration *cfg = &i2cdrv_config[i];
+
+    sc = rtems_io_register_name(cfg->device_name, major, i);
+    assert(sc == RTEMS_SUCCESSFUL);
+
+    sc = rtems_semaphore_create(
+      rtems_build_name ('I', '2', 'C', '0' + i),
+      0,
+      RTEMS_BINARY_SEMAPHORE | RTEMS_PRIORITY | RTEMS_INHERIT_PRIORITY,
+      0,
+      &e->mutex
+    );
+    assert(sc == RTEMS_SUCCESSFUL);
+
+    sc = init_i2c_module(e, cfg);
+    if ( sc != RTEMS_SUCCESSFUL ) {
+      /* I2C is not usable at this point. Releasing the mutex would allow the
+       * usage which could lead to undefined behaviour. */
+      return sc;
+    }
+
+    sc = rtems_semaphore_release(e->mutex);
+    assert(sc == RTEMS_SUCCESSFUL);
+  }
+
+  return sc;
+}
+
+rtems_device_driver i2cdrv_open(
+  rtems_device_major_number major,
+  rtems_device_major_number minor,
+  void *arg
+)
+{
+  rtems_status_code sc = RTEMS_SUCCESSFUL;
+  i2cdrv_entry *e = &i2cdrv_table[minor];
+
+  sc = rtems_semaphore_obtain(e->mutex, RTEMS_WAIT, RTEMS_NO_TIMEOUT);
+  return sc;
+}
+
+rtems_device_driver i2cdrv_close(
+  rtems_device_major_number major,
+  rtems_device_major_number minor,
+  void *arg
+)
+{
+  rtems_status_code sc = RTEMS_SUCCESSFUL;
+  i2cdrv_entry *e = &i2cdrv_table[minor];
+
+  sc = rtems_semaphore_release(e->mutex);
+  return sc;
+}
+
+rtems_device_driver i2cdrv_read(
+  rtems_device_major_number major,
+  rtems_device_major_number minor,
+  void *arg
+)
+{
+  rtems_status_code sc = RTEMS_SUCCESSFUL;
+  i2cdrv_entry *e = &i2cdrv_table[minor];
+  rtems_libio_rw_args_t *rw  = arg;
+  ALT_I2C_DEV_t *dev = get_device(e);
+  ALT_STATUS_CODE asc = ALT_E_SUCCESS;
+
+  asc = alt_i2c_master_receive(dev, rw->buffer, rw->count, true, true);
+  if ( asc == ALT_E_SUCCESS ) {
+    rw->bytes_moved = rw->count;
+  } else {
+    sc = RTEMS_IO_ERROR;
+  }
+
+  return sc;
+}
+
+rtems_device_driver i2cdrv_write(
+  rtems_device_major_number major,
+  rtems_device_minor_number minor,
+  void *arg
+)
+{
+  rtems_status_code sc = RTEMS_SUCCESSFUL;
+  i2cdrv_entry *e = &i2cdrv_table[minor];
+  rtems_libio_rw_args_t *rw  = arg;
+  ALT_I2C_DEV_t *dev = get_device(e);
+  ALT_STATUS_CODE asc = ALT_E_SUCCESS;
+
+  asc = alt_i2c_master_transmit(dev, rw->buffer, rw->count, true, true);
+  if ( asc == ALT_E_SUCCESS ) {
+    rw->bytes_moved = rw->count;
+  } else {
+    sc = RTEMS_IO_ERROR;
+  }
+
+  return sc;
+}
+
+static rtems_status_code ioctl_set_slave_address(
+  i2cdrv_entry *e,
+  rtems_libio_ioctl_args_t *args
+)
+{
+  ALT_I2C_DEV_t *dev = get_device(e);
+  ALT_STATUS_CODE asc = ALT_E_SUCCESS;
+  uint32_t address = (uint32_t) args->buffer;
+
+  asc = alt_i2c_master_target_set(dev, address);
+  if ( asc != ALT_E_SUCCESS ) {
+    return RTEMS_IO_ERROR;
+  }
+
+  return RTEMS_SUCCESSFUL;
+}
+
+rtems_device_driver i2cdrv_ioctl(
+  rtems_device_major_number major,
+  rtems_device_minor_number minor,
+  void *arg
+)
+{
+  rtems_status_code sc = RTEMS_SUCCESSFUL;
+  i2cdrv_entry *e = &i2cdrv_table[minor];
+  rtems_libio_ioctl_args_t *args = arg;
+
+  switch (args->command) {
+    case I2C_IOC_SET_SLAVE_ADDRESS:
+      sc = ioctl_set_slave_address(e, args);
+      break;
+    default:
+      sc = RTEMS_INVALID_NUMBER;
+      break;
+  }
+
+  return sc;
+}