boardd: connect to SPI panda by UID (#27035)

* move list

* connect by serial

* cleanup hw serial

* little more

* rm excessive print

Co-authored-by: Comma Device <device@comma.ai>

selfdrive/boardd/boardd.cc

@@ -225,9 +225,9 @@ void can_send_thread(std::vector<Panda *> pandas, bool fake_send) {
     //Dont send if older than 1 second
     if ((nanos_since_boot() - event.getLogMonoTime() < 1e9) && !fake_send) {
       for (const auto& panda : pandas) {
-        LOGT("sending sendcan to panda: %s", (panda->hw_serial).c_str());
+        LOGT("sending sendcan to panda: %s", (panda->hw_serial()).c_str());
         panda->can_send(event.getSendcan());
-        LOGT("sendcan sent to panda: %s", (panda->hw_serial).c_str());
+        LOGT("sendcan sent to panda: %s", (panda->hw_serial()).c_str());
       }
     }
   }

selfdrive/boardd/panda.cc

@@ -3,20 +3,18 @@
 #include <unistd.h>
 
 #include <cassert>
-#include <iomanip>
 #include <stdexcept>
-#include <sstream>
 
 #include "cereal/messaging/messaging.h"
 #include "common/swaglog.h"
 #include "common/util.h"
 
 Panda::Panda(std::string serial, uint32_t bus_offset) : bus_offset(bus_offset) {
-  // TODO: support SPI here one day...
+  // try USB first, then SPI
-  if (serial.find("spi") != std::string::npos) {
+  try {
-    handle = std::make_unique<PandaSpiHandle>(serial);
-  } else {
     handle = std::make_unique<PandaUsbHandle>(serial);
+  } catch (std::exception &e) {
+    handle = std::make_unique<PandaSpiHandle>(serial);
   }
 
   hw_type = get_hw_type();
@@ -41,23 +39,16 @@ bool Panda::comms_healthy() {
   return handle->comms_healthy;
 }
 
+std::string Panda::hw_serial() {
+  return handle->hw_serial;
+}
+
 std::vector<std::string> Panda::list() {
   std::vector<std::string> serials = PandaUsbHandle::list();
 
-  // check SPI
+  for (auto s : PandaSpiHandle::list()) {
-  const int uid_len = 12;
+    if (std::find(serials.begin(), serials.end(), s) == serials.end()) {
-  uint8_t uid[uid_len] = {0};
+      serials.push_back(s);
-  PandaSpiHandle spi_handle("/dev/spidev0.0");
-  int ret = spi_handle.control_read(0xc3, 0, 0, uid, uid_len);
-  if (ret == uid_len) {
-    std::stringstream stream;
-    for (int i = 0; i < uid_len; i++) {
-      stream << std::hex << std::setw(2) << std::setfill('0') << int(uid[i]);
-    }
-
-    // might be on USB too
-    if (std::find(serials.begin(), serials.end(), stream.str()) == serials.end()) {
-      serials.push_back(stream.str());
     }
   }
 

selfdrive/boardd/panda.h

@@ -48,13 +48,13 @@ private:
 public:
   Panda(std::string serial="", uint32_t bus_offset=0);
 
-  std::string hw_serial;
   cereal::PandaState::PandaType hw_type = cereal::PandaState::PandaType::UNKNOWN;
   bool has_rtc = false;
   const uint32_t bus_offset;
 
   bool connected();
   bool comms_healthy();
+  std::string hw_serial();
 
   // Static functions
   static std::vector<std::string> list();

selfdrive/boardd/panda_comms.cc

@@ -44,7 +44,7 @@ PandaUsbHandle::PandaUsbHandle(std::string serial) : PandaCommsHandle(serial) {
       ret = libusb_get_string_descriptor_ascii(dev_handle, desc.iSerialNumber, desc_serial, std::size(desc_serial));
       if (ret < 0) { goto fail; }
 
-      auto hw_serial = std::string((char *)desc_serial, ret);
+      hw_serial = std::string((char *)desc_serial, ret);
       if (serial.empty() || serial == hw_serial) {
         break;
       }

selfdrive/boardd/panda_comms.h

@@ -21,6 +21,7 @@ public:
   virtual ~PandaCommsHandle() {};
   virtual void cleanup() = 0;
 
+  std::string hw_serial;
   std::atomic<bool> connected = true;
   std::atomic<bool> comms_healthy = true;
   static std::vector<std::string> list();

selfdrive/boardd/spi.cc

@@ -5,6 +5,8 @@
 #include <cassert>
 #include <cmath>
 #include <cstring>
+#include <iomanip>
+#include <sstream>
 
 #include "common/util.h"
 #include "common/timing.h"
@@ -28,6 +30,7 @@ struct __attribute__((packed)) spi_header {
 
 const int SPI_MAX_RETRIES = 5;
 const int SPI_ACK_TIMEOUT = 50; // milliseconds
+const std::string SPI_DEVICE = "/dev/spidev0.0";
 
 class LockEx {
 public:
@@ -48,38 +51,56 @@ private:
 
 
 PandaSpiHandle::PandaSpiHandle(std::string serial) : PandaCommsHandle(serial) {
-  LOGD("opening SPI panda: %s", serial.c_str());
+  int ret;
+  const int uid_len = 12;
+  uint8_t uid[uid_len] = {0};
 
-  int err;
   uint32_t spi_mode = SPI_MODE_0;
   uint32_t spi_speed = 30000000;
   uint8_t spi_bits_per_word = 8;
 
-  spi_fd = open(serial.c_str(), O_RDWR);
+  spi_fd = open(SPI_DEVICE.c_str(), O_RDWR);
   if (spi_fd < 0) {
-    LOGE("failed opening SPI device %d", err);
+    LOGE("failed opening SPI device %d", spi_fd);
     goto fail;
   }
 
   // SPI settings
-  err = util::safe_ioctl(spi_fd, SPI_IOC_WR_MODE, &spi_mode);
+  ret = util::safe_ioctl(spi_fd, SPI_IOC_WR_MODE, &spi_mode);
-  if (err < 0) {
+  if (ret < 0) {
-    LOGE("failed setting SPI mode %d", err);
+    LOGE("failed setting SPI mode %d", ret);
     goto fail;
   }
 
-  err = util::safe_ioctl(spi_fd, SPI_IOC_WR_MAX_SPEED_HZ, &spi_speed);
+  ret = util::safe_ioctl(spi_fd, SPI_IOC_WR_MAX_SPEED_HZ, &spi_speed);
-  if (err < 0) {
+  if (ret < 0) {
     LOGE("failed setting SPI speed");
     goto fail;
   }
 
-  err = util::safe_ioctl(spi_fd, SPI_IOC_WR_BITS_PER_WORD, &spi_bits_per_word);
+  ret = util::safe_ioctl(spi_fd, SPI_IOC_WR_BITS_PER_WORD, &spi_bits_per_word);
-  if (err < 0) {
+  if (ret < 0) {
     LOGE("failed setting SPI bits per word");
     goto fail;
   }
 
+  // get hw UID/serial
+  ret = control_read(0xc3, 0, 0, uid, uid_len);
+  if (ret == uid_len) {
+    std::stringstream stream;
+    for (int i = 0; i < uid_len; i++) {
+      stream << std::hex << std::setw(2) << std::setfill('0') << int(uid[i]);
+    }
+    hw_serial = stream.str();
+  } else {
+    LOGD("failed to get serial %d", ret);
+    goto fail;
+  }
+
+  if (!serial.empty() && (serial != hw_serial)) {
+    goto fail;
+  }
+
   return;
 
 fail:
@@ -163,7 +184,12 @@ int PandaSpiHandle::bulk_transfer(uint8_t endpoint, uint8_t *tx_data, uint16_t t
 }
 
 std::vector<std::string> PandaSpiHandle::list() {
-  // TODO: list all pandas available over SPI
+  try {
+    PandaSpiHandle sh("");
+    return {sh.hw_serial};
+  } catch (std::exception &e) {
+    // no panda on SPI
+  }
   return {};
 }