spicmds: Rework spi config commands

Rework the spi_config commands so that bus configuration and shutdown
message configuration is done separately from the main "config_spi"
command.  This makes the spi configuration more flexible.  It's now
possible to use software spi without a CS pin.  It's now possible to
define multiple SPI messages to send on a shutdown event.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

7 files changed, 86 insertions, 81 deletions

diff --git a/src/atsamd/spi.c b/src/atsamd/spi.c
index 67c68cea..02aad5d3 100644
--- a/src/atsamd/spi.c
+++ b/src/atsamd/spi.c
@@ -6,9 +6,7 @@
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
 #include "internal.h" // enable_pclock
-#include "command.h" // shutdown
 #include "gpio.h" // spi_setup
-#include "sched.h" // sched_shutdown
 
 void
 spi_init(uint32_t bus, SercomSpi *ss, uint32_t ctrla, uint32_t baud)
diff --git a/src/basecmd.c b/src/basecmd.c
index 95511885..7b402ca1 100644
--- a/src/basecmd.c
+++ b/src/basecmd.c
@@ -27,7 +27,7 @@ alloc_init(void)
 DECL_INIT(alloc_init);
 
 // Allocate an area of memory
-static void *
+void *
 alloc_chunk(size_t size)
 {
     if (alloc_end + size > dynmem_end())
diff --git a/src/basecmd.h b/src/basecmd.h
index 21555bf8..f4ea1cc7 100644
--- a/src/basecmd.h
+++ b/src/basecmd.h
@@ -1,8 +1,10 @@
 #ifndef __BASECMD_H
 #define __BASECMD_H
 
+#include <stddef.h> // size_t
 #include <stdint.h> // uint8_t
 
+void *alloc_chunk(size_t size);
 void move_free(void *m);
 void *move_alloc(void);
 void move_request_size(int size);
diff --git a/src/linux/spidev.c b/src/linux/spidev.c
index 5c613cba..764541e3 100644
--- a/src/linux/spidev.c
+++ b/src/linux/spidev.c
@@ -97,13 +97,13 @@ spi_transfer(struct spi_config config, uint8_t receive_data
         int ret = ioctl(config.fd, SPI_IOC_MESSAGE(1), &transfer);
         if (ret < 0) {
             report_errno("spi ioctl", ret);
-            shutdown("Unable to issue spi ioctl");
+            try_shutdown("Unable to issue spi ioctl");
         }
     } else {
         int ret = write(config.fd, data, len);
         if (ret < 0) {
             report_errno("write spi", ret);
-            shutdown("Unable to write to spi");
+            try_shutdown("Unable to write to spi");
         }
     }
 }
diff --git a/src/spi_software.c b/src/spi_software.c
index 2d086f78..345e2f81 100644
--- a/src/spi_software.c
+++ b/src/spi_software.c
@@ -9,39 +9,33 @@
 #include "basecmd.h" // oid_alloc
 #include "command.h" // DECL_COMMAND
 #include "sched.h" // sched_shutdown
+#include "spicmds.h" // spidev_set_software_bus
 
 struct spi_software {
-    struct gpio_out sclk, mosi;
     struct gpio_in miso;
+    struct gpio_out mosi, sclk;
     uint8_t mode;
 };
 
 void
-command_config_software_spi(uint32_t *args)
+command_spi_set_software_bus(uint32_t *args)
 {
-    uint8_t oid = args[0], sclk_pin = args[1], mosi_pin = args[2];
-    uint8_t miso_pin = args[3], mode = args[4];
+    uint8_t mode = args[4];
     if (mode > 3)
-        shutdown("Invalid spi mode");
+        shutdown("Invalid spi config");
 
-    struct spi_software *spi = oid_alloc(oid, command_config_software_spi
-                                         , sizeof(*spi));
-
-    spi->sclk = gpio_out_setup(sclk_pin, 0);
-    spi->mosi = gpio_out_setup(mosi_pin, 0);
-    spi->miso = gpio_in_setup(miso_pin, 1);
-    spi->mode = mode;
+    struct spidev_s *spi = spidev_oid_lookup(args[0]);
+    struct spi_software *ss = alloc_chunk(sizeof(*ss));
+    ss->miso = gpio_in_setup(args[1], 1);
+    ss->mosi = gpio_out_setup(args[2], 0);
+    ss->sclk = gpio_out_setup(args[3], 0);
+    ss->mode = mode;
+    spidev_set_software_bus(spi, ss);
 }
-DECL_COMMAND(command_config_software_spi,
-             "config_software_spi oid=%c sclk_pin=%u mosi_pin=%u miso_pin=%u"
+DECL_COMMAND(command_spi_set_software_bus,
+             "spi_set_software_bus oid=%c miso_pin=%u mosi_pin=%u sclk_pin=%u"
              " mode=%u rate=%u");
 
-struct spi_software *
-spi_software_oid_lookup(uint8_t oid)
-{
-    return oid_lookup(oid, command_config_software_spi);
-}
-
 void
 spi_software_prepare(struct spi_software *ss)
 {
diff --git a/src/spicmds.c b/src/spicmds.c
index 527cb0af..654e9436 100644
--- a/src/spicmds.c
+++ b/src/spicmds.c
@@ -1,6 +1,6 @@
 // Commands for sending messages on an SPI bus
 //
-// Copyright (C) 2016-2018  Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2016-2019  Kevin O'Connor <kevin@koconnor.net>
 //
 // This file may be distributed under the terms of the GNU GPLv3 license.
 
@@ -20,80 +20,64 @@ struct spidev_s {
     };
     struct gpio_out pin;
     uint8_t flags;
-    uint8_t shutdown_msg_len;
-    uint8_t shutdown_msg[];
 };
 
 enum {
-    SF_HAVE_PIN = 1, SF_SOFTWARE = 2,
+    SF_HAVE_PIN = 1, SF_SOFTWARE = 2, SF_HARDWARE = 4,
 };
 
 void
 command_config_spi(uint32_t *args)
 {
-    uint8_t mode = args[3], shutdown_msg_len = args[5];
-    if (mode > 3)
-        shutdown("Invalid spi mode");
-    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], mode, 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);
+    struct spidev_s *spi = oid_alloc(args[0], command_config_spi, sizeof(*spi));
+    spi->pin = gpio_out_setup(args[1], 1);
+    spi->flags |= SF_HAVE_PIN;
 }
-DECL_COMMAND(command_config_spi,
-             "config_spi oid=%c spi_bus=%u pin=%u mode=%u rate=%u"
-             " shutdown_msg=%*s");
+DECL_COMMAND(command_config_spi, "config_spi oid=%c pin=%u");
 
 void
 command_config_spi_without_cs(uint32_t *args)
 {
-    uint8_t mode = args[2], shutdown_msg_len = args[4];
-    if (mode > 3)
-        shutdown("Invalid spi mode");
-    struct spidev_s *spi = oid_alloc(args[0], command_config_spi
-                                     , sizeof(*spi) + shutdown_msg_len);
-    spi->spi_config = spi_setup(args[1], mode, 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);
+    struct spidev_s *spi = oid_alloc(args[0], command_config_spi, sizeof(*spi));
+}
+DECL_COMMAND(command_config_spi_without_cs, "config_spi_without_cs oid=%c");
+
+struct spidev_s *
+spidev_oid_lookup(uint8_t oid)
+{
+    return oid_lookup(oid, command_config_spi);
 }
-DECL_COMMAND(command_config_spi_without_cs,
-             "config_spi_without_cs oid=%c spi_bus=%u mode=%u rate=%u"
-             " shutdown_msg=%*s");
 
 void
-command_config_spi_from_software(uint32_t *args)
+command_spi_set_bus(uint32_t *args)
 {
-    uint8_t shutdown_msg_len = args[3];
-    struct spi_software *sspi = spi_software_oid_lookup(args[1]);
-    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 | SF_SOFTWARE;
-    spi->spi_software = sspi;
-    spi->shutdown_msg_len = shutdown_msg_len;
-    uint8_t *shutdown_msg = (void*)(size_t)args[4];
-    memcpy(spi->shutdown_msg, shutdown_msg, shutdown_msg_len);
+    struct spidev_s *spi = spidev_oid_lookup(args[0]);
+    uint8_t mode = args[2];
+    if (mode > 3 || spi->flags & (SF_SOFTWARE|SF_HARDWARE))
+        shutdown("Invalid spi config");
+    spi->spi_config = spi_setup(args[1], mode, args[3]);
+    spi->flags |= SF_HARDWARE;
 }
-#if CONFIG_HAVE_GPIO_BITBANGING
-DECL_COMMAND(command_config_spi_from_software,
-             "config_spi_from_software oid=%c sw_oid=%u pin=%u"
-             " shutdown_msg=%*s");
-#endif
+DECL_COMMAND(command_spi_set_bus,
+             "spi_set_bus oid=%c spi_bus=%u mode=%u rate=%u");
 
-struct spidev_s *
-spidev_oid_lookup(uint8_t oid)
+void
+spidev_set_software_bus(struct spidev_s *spi, struct spi_software *ss)
 {
-    return oid_lookup(oid, command_config_spi);
+    if (spi->flags & (SF_SOFTWARE|SF_HARDWARE))
+        shutdown("Invalid spi config");
+    spi->spi_software = ss;
+    spi->flags |= SF_SOFTWARE;
 }
 
 void
 spidev_transfer(struct spidev_s *spi, uint8_t receive_data
                 , uint8_t data_len, uint8_t *data)
 {
+    if (!(spi->flags & (SF_SOFTWARE|SF_HARDWARE)))
+        // Not yet initialized
+        return;
+
     if (CONFIG_HAVE_GPIO_BITBANGING && spi->flags & SF_SOFTWARE)
         spi_software_prepare(spi->spi_software);
     else
@@ -115,7 +99,7 @@ void
 command_spi_transfer(uint32_t *args)
 {
     uint8_t oid = args[0];
-    struct spidev_s *spi = oid_lookup(oid, command_config_spi);
+    struct spidev_s *spi = spidev_oid_lookup(oid);
     uint8_t data_len = args[1];
     uint8_t *data = (void*)(size_t)args[2];
     spidev_transfer(spi, 1, data_len, data);
@@ -126,14 +110,39 @@ DECL_COMMAND(command_spi_transfer, "spi_transfer oid=%c data=%*s");
 void
 command_spi_send(uint32_t *args)
 {
-    uint8_t oid = args[0];
-    struct spidev_s *spi = oid_lookup(oid, command_config_spi);
+    struct spidev_s *spi = spidev_oid_lookup(args[0]);
     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");
 
+
+/****************************************************************
+ * Shutdown handling
+ ****************************************************************/
+
+struct spidev_shutdown_s {
+    struct spidev_s *spi;
+    uint8_t shutdown_msg_len;
+    uint8_t shutdown_msg[];
+};
+
+void
+command_config_spi_shutdown(uint32_t *args)
+{
+    struct spidev_s *spi = spidev_oid_lookup(args[1]);
+    uint8_t shutdown_msg_len = args[2];
+    struct spidev_shutdown_s *sd = oid_alloc(
+        args[0], command_config_spi_shutdown, sizeof(*sd) + shutdown_msg_len);
+    sd->spi = spi;
+    sd->shutdown_msg_len = shutdown_msg_len;
+    uint8_t *shutdown_msg = (void*)(size_t)args[3];
+    memcpy(sd->shutdown_msg, shutdown_msg, shutdown_msg_len);
+}
+DECL_COMMAND(command_config_spi_shutdown,
+             "config_spi_shutdown oid=%c spi_oid=%c shutdown_msg=%*s");
+
 void
 spidev_shutdown(void)
 {
@@ -146,9 +155,9 @@ spidev_shutdown(void)
     }
 
     // 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);
+    struct spidev_shutdown_s *sd;
+    foreach_oid(oid, sd, command_config_spi_shutdown) {
+        spidev_transfer(sd->spi, 0, sd->shutdown_msg_len, sd->shutdown_msg);
     }
 }
 DECL_SHUTDOWN(spidev_shutdown);
diff --git a/src/spicmds.h b/src/spicmds.h
index dee50665..959fddb9 100644
--- a/src/spicmds.h
+++ b/src/spicmds.h
@@ -4,7 +4,9 @@
 #include <stdint.h> // uint8_t
 
 struct spidev_s *spidev_oid_lookup(uint8_t oid);
+struct spi_software;
+void spidev_set_software_bus(struct spidev_s *spi, struct spi_software *ss);
 void spidev_transfer(struct spidev_s *spi, uint8_t receive_data
                      , uint8_t data_len, uint8_t *data);
 
-#endif // stepper.h
+#endif // spicmds.h