spicmds: Rework SPI message transmission

Improve the SPI message transmit system.  Add support for bus speed
and bus mode.  Add support for sending SPI messages on shutdown.

Signed-off-by: Petri Honkala <cruwaller@gmail.com>
Signed-off-by: Douglas Hammond <wizhippo@gmail.com>
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 98 insertions, 11 deletions

diff --git a/src/spicmds.c b/src/spicmds.c
index bb37be2b..f87972a0 100644
--- a/src/spicmds.c
+++ b/src/spicmds.c
@@ -1,22 +1,109 @@
 // Commands for sending messages on an SPI bus
 //
-// Copyright (C) 2016  Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2016-2018  Kevin O'Connor <kevin@koconnor.net>
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
+#include <string.h> // memcpy
 #include "board/gpio.h" // gpio_out_write
+#include "basecmd.h" // oid_alloc
 #include "command.h" // DECL_COMMAND
+#include "sched.h" // DECL_SHUTDOWN
+
+struct spidev_s {
+    struct spi_config spi_config;
+    struct gpio_out pin;
+    uint8_t flags;
+    uint8_t shutdown_msg_len;
+    uint8_t shutdown_msg[];
+};
+
+enum {
+    SF_HAVE_PIN = 1,
+};
+
+void
+command_config_spi(uint32_t *args)
+{
+    uint8_t shutdown_msg_len = args[5];
+    struct spidev_s *spi = oid_alloc(args[0], command_config_spi
+                                     , sizeof(*spi) + shutdown_msg_len);
+    spi->pin = gpio_out_setup(args[2], 1);
+    spi->flags = SF_HAVE_PIN;
+    spi->spi_config = spi_setup(args[1], args[3], args[4]);
+    spi->shutdown_msg_len = shutdown_msg_len;
+    uint8_t *shutdown_msg = (void*)(size_t)args[6];
+    memcpy(spi->shutdown_msg, shutdown_msg, shutdown_msg_len);
+}
+DECL_COMMAND(command_config_spi,
+             "config_spi oid=%c bus=%u pin=%u mode=%u rate=%u shutdown_msg=%*s");
+
+void
+command_config_spi_without_cs(uint32_t *args)
+{
+    uint8_t shutdown_msg_len = args[4];
+    struct spidev_s *spi = oid_alloc(args[0], command_config_spi
+                                     , sizeof(*spi) + shutdown_msg_len);
+    spi->spi_config = spi_setup(args[1], args[2], args[3]);
+    spi->shutdown_msg_len = shutdown_msg_len;
+    uint8_t *shutdown_msg = (void*)(size_t)args[5];
+    memcpy(spi->shutdown_msg, shutdown_msg, shutdown_msg_len);
+}
+DECL_COMMAND(command_config_spi_without_cs,
+             "config_spi_without_cs oid=%c bus=%u mode=%u rate=%u"
+             " shutdown_msg=%*s");
+
+static void
+spidev_transfer(struct spidev_s *spi, uint8_t receive_data
+                , uint8_t data_len, uint8_t *data)
+{
+    if (spi->flags & SF_HAVE_PIN) {
+        gpio_out_write(spi->pin, 0);
+        spi_transfer(spi->spi_config, receive_data, data_len, data);
+        gpio_out_write(spi->pin, 1);
+    } else {
+        spi_transfer(spi->spi_config, receive_data, data_len, data);
+    }
+}
+
+void
+command_spi_transfer(uint32_t *args)
+{
+    uint8_t oid = args[0];
+    struct spidev_s *spi = oid_lookup(oid, command_config_spi);
+    uint8_t data_len = args[1];
+    uint8_t *data = (void*)(size_t)args[2];
+    spidev_transfer(spi, 1, data_len, data);
+    sendf("spi_transfer_response oid=%c response=%*s", oid, data_len, data);
+}
+DECL_COMMAND(command_spi_transfer, "spi_transfer oid=%c data=%*s");
 
 void
-command_send_spi_message(uint32_t *args)
+command_spi_send(uint32_t *args)
 {
-    // For now, this only implements enough to program an ad5206 digipot
-    uint8_t len = args[1];
-    char *msg = (void*)(size_t)args[2];
-    spi_config();
-    struct gpio_out pin = gpio_out_setup(args[0], 0);
-    spi_transfer(msg, len);
-    gpio_out_write(pin, 1);
-    sendf("spi_response response=%*s", len, msg);
+    uint8_t oid = args[0];
+    struct spidev_s *spi = oid_lookup(oid, command_config_spi);
+    uint8_t data_len = args[1];
+    uint8_t *data = (void*)(size_t)args[2];
+    spidev_transfer(spi, 0, data_len, data);
+}
+DECL_COMMAND(command_spi_send, "spi_send oid=%c data=%*s");
+
+void
+spidev_shutdown(void)
+{
+    // Cancel any transmissions that may be in progress
+    uint8_t oid;
+    struct spidev_s *spi;
+    foreach_oid(oid, spi, command_config_spi) {
+        if (spi->flags & SF_HAVE_PIN)
+            gpio_out_write(spi->pin, 1);
+    }
+
+    // Send shutdown messages
+    foreach_oid(oid, spi, command_config_spi) {
+        if (spi->shutdown_msg_len)
+            spidev_transfer(spi, 0, spi->shutdown_msg_len, spi->shutdown_msg);
+    }
 }
-DECL_COMMAND(command_send_spi_message, "send_spi_message pin=%u msg=%*s");
+DECL_SHUTDOWN(spidev_shutdown);