feat(epicardium): USB serial support

epicardium/cdcacm.c

+/*******************************************************************************
+ * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
+ * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Except as contained in this notice, the name of Maxim Integrated
+ * Products, Inc. shall not be used except as stated in the Maxim Integrated
+ * Products, Inc. Branding Policy.
+ *
+ * The mere transfer of this software does not imply any licenses
+ * of trade secrets, proprietary technology, copyrights, patents,
+ * trademarks, maskwork rights, or any other form of intellectual
+ * property whatsoever. Maxim Integrated Products, Inc. retains all
+ * ownership rights.
+ *
+ * $Id: main.c 32120 2017-11-28 23:51:11Z lorne.smith $
+ *
+ *******************************************************************************
+ */
+
+/**
+ * @file    main.c
+ * @brief   USB CDC-ACM example
+ * @details This project creates a virtual COM port, which loops back data sent to it.
+ *          Load the project, connect a cable from the PC to the USB connector
+ *          on the Evaluation Kit, and observe that the PC now recognizes a new COM port.
+ *          A driver for the COM port, if needed, is located in the Driver/ subdirectory.
+ *
+ */
+
+#include <stdio.h>
+#include <stddef.h>
+#include "mxc_config.h"
+#include "mxc_sys.h"
+#include "mxc_delay.h"
+#include "board.h"
+#include "led.h"
+#include "usb.h"
+#include "usb_event.h"
+#include "enumerate.h"
+#include "cdc_acm.h"
+#include "descriptors.h"
+
+
+/***** Definitions *****/
+#define EVENT_ENUM_COMP     MAXUSB_NUM_EVENTS
+
+#define BUFFER_SIZE  64
+
+#define STRINGIFY(x) #x
+#define TOSTRING(x) STRINGIFY(x)
+
+/***** Global Data *****/
+volatile int configured;
+volatile int suspended;
+volatile unsigned int event_flags;
+int remote_wake_en;
+
+/***** Function Prototypes *****/
+static int setconfig_callback(usb_setup_pkt *sud, void *cbdata);
+static int setfeature_callback(usb_setup_pkt *sud, void *cbdata);
+static int clrfeature_callback(usb_setup_pkt *sud, void *cbdata);
+static int event_callback(maxusb_event_t evt, void *data);
+static void usb_app_sleep(void);
+static void usb_app_wakeup(void);
+static int usb_read_callback(void);
+//static void echo_usb(void);
+
+/***** File Scope Variables *****/
+
+/* This EP assignment must match the Configuration Descriptor */
+static const acm_cfg_t acm_cfg = {
+  1,                  /* EP OUT */
+  MXC_USBHS_MAX_PACKET, /* OUT max packet size */
+  2,                  /* EP IN */
+  MXC_USBHS_MAX_PACKET, /* IN max packet size */
+  3,                  /* EP Notify */
+  MXC_USBHS_MAX_PACKET, /* Notify max packet size */
+};
+
+static volatile int usb_read_complete;
+
+int usb_startup_cb()
+{
+    const sys_cfg_usbhs_t sys_usbhs_cfg = NULL;
+    return SYS_USBHS_Init(&sys_usbhs_cfg);
+}
+
+int usb_shutdown_cb()
+{
+    return SYS_USBHS_Shutdown();
+}
+
+/* User-supplied function to delay usec micro-seconds */
+void delay_us(unsigned int usec)
+{
+    /* mxc_delay() takes unsigned long, so can't use it directly */
+    mxc_delay(usec);
+}
+
+
+/******************************************************************************/
+void cdcacm_init(void)
+{
+    maxusb_cfg_options_t usb_opts;
+
+    /* Initialize state */
+    configured = 0;
+    suspended = 0;
+    event_flags = 0;
+    remote_wake_en = 0;
+
+    /* Start out in full speed */
+    usb_opts.enable_hs = 0;
+    usb_opts.delay_us = delay_us; /* Function which will be used for delays */
+    usb_opts.init_callback = usb_startup_cb;
+    usb_opts.shutdown_callback = usb_shutdown_cb;
+
+    /* Initialize the usb module */
+    if (usb_init(&usb_opts) != 0) {
+        printf("usb_init() failed\n");
+        while (1);
+    }
+
+    /* Initialize the enumeration module */
+    if (enum_init() != 0) {
+        printf("enum_init() failed\n");
+        while (1);
+    }
+
+    /* Register enumeration data */
+    enum_register_descriptor(ENUM_DESC_DEVICE, (uint8_t*)&device_descriptor, 0);
+    enum_register_descriptor(ENUM_DESC_CONFIG, (uint8_t*)&config_descriptor, 0);
+    enum_register_descriptor(ENUM_DESC_STRING, lang_id_desc, 0);
+    enum_register_descriptor(ENUM_DESC_STRING, mfg_id_desc, 1);
+    enum_register_descriptor(ENUM_DESC_STRING, prod_id_desc, 2);
+
+    /* Handle configuration */
+    enum_register_callback(ENUM_SETCONFIG, setconfig_callback, NULL);
+
+    /* Handle feature set/clear */
+    enum_register_callback(ENUM_SETFEATURE, setfeature_callback, NULL);
+    enum_register_callback(ENUM_CLRFEATURE, clrfeature_callback, NULL);
+
+    /* Initialize the class driver */
+    if (acm_init(&config_descriptor.comm_interface_descriptor) != 0) {
+        printf("acm_init() failed\n");
+        while (1);
+    }
+
+    /* Register callbacks */
+    usb_event_enable(MAXUSB_EVENT_NOVBUS, event_callback, NULL);
+    usb_event_enable(MAXUSB_EVENT_VBUS, event_callback, NULL);
+    acm_register_callback(ACM_CB_READ_READY, usb_read_callback);
+    usb_read_complete = 0;
+
+    /* Start with USB in low power mode */
+    usb_app_sleep();
+    NVIC_EnableIRQ(USB_IRQn);
+}
+
+int cdcacm_num_read_avail(void)
+{
+    return acm_canread();
+}
+
+uint8_t cdcacm_read(void)
+{
+    while(acm_canread() <= 0) {
+    }
+
+    uint8_t buf;
+    acm_read(&buf, 1);
+    return buf;
+}
+
+void cdcacm_write(uint8_t *data, int len)
+{
+    while (acm_present()) {
+        // TODO: This might fail horribly
+        if (acm_write(data, len) == len) {
+            break;
+        }
+    }
+}
+
+
+/******************************************************************************/
+#if 0
+static void echo_usb(void)
+{
+  int chars;
+  uint8_t buffer[BUFFER_SIZE];
+  
+  if ((chars = acm_canread()) > 0) {
+
+    if (chars > BUFFER_SIZE) {
+      chars = BUFFER_SIZE;
+    }
+
+    // Read the data from USB
+    if (acm_read(buffer, chars) != chars) {
+      printf("acm_read() failed\n");
+      return;
+    }
+
+    // Echo it back
+    if (acm_present()) {
+      if (acm_write(buffer, chars) != chars) {
+        printf("acm_write() failed\n");
+      }
+    }
+  }
+}
+#endif
+/******************************************************************************/
+static int setconfig_callback(usb_setup_pkt *sud, void *cbdata)
+{
+    /* Confirm the configuration value */
+    if (sud->wValue == config_descriptor.config_descriptor.bConfigurationValue) {
+        configured = 1;
+        MXC_SETBIT(&event_flags, EVENT_ENUM_COMP);
+        return acm_configure(&acm_cfg); /* Configure the device class */
+    } else if (sud->wValue == 0) {
+        configured = 0;
+        return acm_deconfigure();
+    }
+
+    return -1;
+}
+
+/******************************************************************************/
+static int setfeature_callback(usb_setup_pkt *sud, void *cbdata)
+{
+    if(sud->wValue == FEAT_REMOTE_WAKE) {
+        remote_wake_en = 1;
+    } else {
+        // Unknown callback
+        return -1;
+    }
+
+    return 0;
+}
+
+/******************************************************************************/
+static int clrfeature_callback(usb_setup_pkt *sud, void *cbdata)
+{
+    if(sud->wValue == FEAT_REMOTE_WAKE) {
+        remote_wake_en = 0;
+    } else {
+        // Unknown callback
+        return -1;
+    }
+    
+    return 0;
+}
+
+/******************************************************************************/
+static void usb_app_sleep(void)
+{
+    /* TODO: Place low-power code here */
+    suspended = 1;
+}
+
+/******************************************************************************/
+static void usb_app_wakeup(void)
+{
+    /* TODO: Place low-power code here */
+    suspended = 0;
+}
+
+/******************************************************************************/
+static int event_callback(maxusb_event_t evt, void *data)
+{
+    /* Set event flag */
+    MXC_SETBIT(&event_flags, evt);
+
+    switch (evt) {
+        case MAXUSB_EVENT_NOVBUS:
+            usb_event_disable(MAXUSB_EVENT_BRST);
+            usb_event_disable(MAXUSB_EVENT_SUSP);
+            usb_event_disable(MAXUSB_EVENT_DPACT);
+            usb_disconnect();
+            configured = 0;
+            enum_clearconfig();
+            acm_deconfigure();
+            usb_app_sleep();
+            break;
+        case MAXUSB_EVENT_VBUS:
+            usb_event_clear(MAXUSB_EVENT_BRST);
+            usb_event_enable(MAXUSB_EVENT_BRST, event_callback, NULL);
+            usb_event_clear(MAXUSB_EVENT_SUSP);
+            usb_event_enable(MAXUSB_EVENT_SUSP, event_callback, NULL);
+            usb_connect();
+            usb_app_sleep();
+            break;
+        case MAXUSB_EVENT_BRST:
+            usb_app_wakeup();
+            enum_clearconfig();
+            acm_deconfigure();
+            configured = 0;
+            suspended = 0;
+            break;
+        case MAXUSB_EVENT_SUSP:
+            usb_app_sleep();
+            break;
+        case MAXUSB_EVENT_DPACT:
+            usb_app_wakeup();
+            break;
+        default:
+            break;
+    }
+
+    return 0;
+}
+
+/******************************************************************************/
+static int usb_read_callback(void)
+{
+    usb_read_complete = 1;
+    return 0;
+}
+
+/******************************************************************************/
+void USB_IRQHandler(void)
+{
+    usb_event_handler();
+}
+
+/******************************************************************************/
+void SysTick_Handler(void)
+{
+    mxc_delay_handler();
+}

epicardium/cdcacm.h

+#ifndef CDCACM_H
+#define CDCACM_H
+
+void cdcacm_init(void);
+int cdcacm_num_read_avail(void);
+uint8_t cdcacm_read(void);
+void cdcacm_write(uint8_t *data, int len);
+
+#endif

epicardium/descriptors.h

+/*******************************************************************************
+ * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
+ * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Except as contained in this notice, the name of Maxim Integrated
+ * Products, Inc. shall not be used except as stated in the Maxim Integrated
+ * Products, Inc. Branding Policy.
+ *
+ * The mere transfer of this software does not imply any licenses
+ * of trade secrets, proprietary technology, copyrights, patents,
+ * trademarks, maskwork rights, or any other form of intellectual
+ * property whatsoever. Maxim Integrated Products, Inc. retains all
+ * ownership rights.
+ *
+ * Description: Communications Device Class ACM (Serial Port) over USB
+ * $Id: descriptors.h 36682 2018-08-06 21:14:03Z michael.bayern $
+ *
+ *******************************************************************************
+ */
+
+#ifndef _DESCRIPTORS_H_
+#define _DESCRIPTORS_H_
+
+#include <stdint.h>
+#include "usb.h"
+#include "hid_kbd.h"
+
+usb_device_descriptor_t __attribute__((aligned(4))) device_descriptor = {
+    0x12,         /* bLength = 18                     */
+    0x01,         /* bDescriptorType = Device         */
+    0x0110,       /* bcdUSB USB spec rev (BCD)        */
+    0x02,         /* bDeviceClass = comm class (2)    */
+    0x00,         /* bDeviceSubClass                  */
+    0x00,         /* bDeviceProtocol                  */
+    0x40,         /* bMaxPacketSize0 is 64 bytes      */
+    0x0B6A,       /* idVendor (Maxim Integrated)      */
+    0x003C,       /* idProduct                        */
+    0x0100,       /* bcdDevice                        */
+    0x01,         /* iManufacturer Descriptor ID      */
+    0x02,         /* iProduct Descriptor ID           */
+    0x00,         /* iSerialNumber = (0) No string    */
+    0x01          /* bNumConfigurations               */
+};
+
+__attribute__((aligned(4)))
+struct __attribute__((packed)) {
+    usb_configuration_descriptor_t  config_descriptor;
+    usb_interface_descriptor_t      comm_interface_descriptor;
+    uint8_t                         header_functional_descriptor[5];
+    uint8_t                         call_management_descriptor[5];
+    uint8_t                         acm_functional_descriptor[4];
+    uint8_t                         union_functional_descriptor[5];
+    usb_endpoint_descriptor_t       endpoint_descriptor_3;
+    usb_interface_descriptor_t      data_interface_descriptor;
+    usb_endpoint_descriptor_t       endpoint_descriptor_1;
+    usb_endpoint_descriptor_t       endpoint_descriptor_2;
+} config_descriptor =
+{
+    {
+        0x09,       /*  bLength = 9                     */
+        0x02,       /*  bDescriptorType = Config (2)    */
+        0x0043,     /*  wTotalLength(L/H)               */
+        0x02,       /*  bNumInterfaces                  */
+        0x01,       /*  bConfigValue                    */
+        0x00,       /*  iConfiguration                  */
+        0xE0,       /*  bmAttributes (self-powered, remote wakeup) */
+        0x01,       /*  MaxPower is 2ma (units are 2ma/bit) */
+    },
+    { /*  First Interface Descriptor For Comm Class Interface */
+        0x09,       /*  bLength = 9                     */
+        0x04,       /*  bDescriptorType = Interface (4) */
+        0x00,       /*  bInterfaceNumber                */
+        0x00,       /*  bAlternateSetting               */
+        0x01,       /*  bNumEndpoints (one for OUT)     */
+        0x02,       /*  bInterfaceClass = Communications Interface Class (2) */
+        0x02,       /*  bInterfaceSubClass = Abstract Control Model (2) */
+        0x01,       /*  bInterfaceProtocol = Common "AT" commands (1), no class specific protocol (0) */
+        0x00,       /*  iInterface                      */
+    },
+    { /*  Header Functional Descriptor */
+        0x05,         /*  bFunctionalLength = 5           */
+        0x24,         /*  bDescriptorType                 */
+        0x00,         /*  bDescriptorSubtype              */
+        0x10, 0x01,   /*  bcdCDC                          */
+    },
+    { /*  Call Management Descriptor */
+        0x05,         /*  bFunctionalLength = 5           */
+        0x24,         /*  bDescriptorType                 */
+        0x01,         /*  bDescriptorSubtype              */
+        0x03,         /*  bmCapabilities = Device handles call management itself (0x01), management over data class (0x02) */
+        0x01,         /*  bmDataInterface                 */
+    },
+    { /*  Abstract Control Management Functional Descriptor */
+        0x04,         /*  bFunctionalLength = 4           */
+        0x24,         /*  bDescriptorType                 */
+        0x02,         /*  bDescriptorSubtype              */
+        0x02,         /*  bmCapabilities                  */
+    },
+    { /*  Union Functional Descriptor */
+        0x05,         /*  bFunctionalLength = 5           */
+        0x24,         /*  bDescriptorType                 */
+        0x06,         /*  bDescriptorSubtype              */
+        0x00,         /*  bmMasterInterface               */
+        0x01,         /*  bmSlaveInterface0               */
+    },
+    { /*  IN Endpoint 3 (Descriptor #1) */
+        0x07,         /*  bLength                          */
+        0x05,         /*  bDescriptorType (Endpoint)       */
+        0x83,         /*  bEndpointAddress (EP3-IN)        */
+        0x03,         /*  bmAttributes (interrupt)         */
+        0x0040,       /*  wMaxPacketSize                   */
+        0xff,         /*  bInterval (milliseconds)         */
+    },
+    { /*  Second Interface Descriptor For Data Interface */
+        0x09,         /*  bLength                          */
+        0x04,         /*  bDescriptorType (Interface)      */
+        0x01,         /*  bInterfaceNumber                 */
+        0x00,         /*  bAlternateSetting                */
+        0x02,         /*  bNumEndpoints                    */
+        0x0a,         /*  bInterfaceClass = Data Interface (10) */
+        0x00,         /*  bInterfaceSubClass = none (0)    */
+        0x00,         /*  bInterfaceProtocol = No class specific protocol (0) */
+        0x00,         /*  biInterface = No Text String (0) */
+    },
+    { /*  OUT Endpoint 1 (Descriptor #2) */
+        0x07,         /*  bLength                          */
+        0x05,         /*  bDescriptorType (Endpoint)       */
+        0x01,         /*  bEndpointAddress (EP1-OUT)       */
+        0x02,         /*  bmAttributes (bulk)              */
+        0x0040,       /*  wMaxPacketSize                   */
+        0x00,         /*  bInterval (N/A)                  */
+    },
+    { /*  IN Endpoint 2 (Descriptor #3) */
+        0x07,         /*  bLength                          */
+        0x05,         /*  bDescriptorType (Endpoint)       */
+        0x82,         /*  bEndpointAddress (EP2-IN)        */
+        0x02,         /*  bmAttributes (bulk)              */
+        0x0040,       /*  wMaxPacketSize                   */
+        0x00          /*  bInterval (N/A)                  */
+    }
+};
+
+__attribute__((aligned(4)))
+uint8_t lang_id_desc[] = {
+    0x04,         /* bLength */
+    0x03,         /* bDescriptorType */
+    0x09, 0x04    /* bString = wLANGID (see usb_20.pdf 9.6.7 String) */
+};
+
+__attribute__((aligned(4)))
+uint8_t mfg_id_desc[] = {
+    0x22,         /* bLength */
+    0x03,         /* bDescriptorType */
+    'M', 0,
+    'a', 0,
+    'x', 0,
+    'i', 0,
+    'm', 0,
+    ' ', 0,
+    'I', 0,
+    'n', 0,
+    't', 0,
+    'e', 0,
+    'g', 0,
+    'r', 0,
+    'a', 0,
+    't', 0,
+    'e', 0,
+    'd', 0,
+};
+
+__attribute__((aligned(4)))
+uint8_t prod_id_desc[] = {
+    0x22,         /* bLength */
+    0x03,         /* bDescriptorType */
+    'M', 0,
+    'A', 0,
+    'X', 0,
+    '3', 0,
+    '2', 0,
+    '6', 0,
+    '6', 0,
+    '5', 0,
+    ' ', 0,
+    'C', 0,
+    'D', 0,
+    'C', 0,
+    '-', 0,
+    'A', 0,
+    'C', 0,
+    'M', 0,
+};
+
+/* Not currently used (see device descriptor), but could be enabled if desired */
+__attribute__((aligned(4)))
+uint8_t serial_id_desc[] = {
+    0x14,         /* bLength */
+    0x03,         /* bDescriptorType */
+    '0', 0,
+    '0', 0,
+    '0', 0,
+    '0', 0,
+    '0', 0,
+    '0', 0,
+    '0', 0,
+    '0', 0,
+    '1', 0
+};
+
+#endif /* _DESCRIPTORS_H_ */

epicardium/main.c

 #include <stdio.h>
 #include "card10.h"
 #include "uart.h"
+#include "cdcacm.h"
 #include "api/dispatcher.h"
 
 extern mxc_uart_regs_t * ConsoleUart;
@@ -8,11 +9,20 @@ extern mxc_uart_regs_t * ConsoleUart;
 void epic_uart_write_str(char*str, intptr_t length)
 {
 	UART_Write(ConsoleUart, (uint8_t*)str, length);
+    cdcacm_write((uint8_t*)str, length);
 }
 
 char epic_uart_read_chr(void)
 {
-	return UART_ReadByte(ConsoleUart);
+    while(1) {
+        if(UART_NumReadAvail(ConsoleUart) > 0) {
+	        return UART_ReadByte(ConsoleUart);
+        }
+
+        if(cdcacm_num_read_avail() > 0) {
+            return cdcacm_read();
+        }
+    }
 }
 
 void epic_leds_set(int led, uint8_t r, uint8_t g, uint8_t b)
@@ -26,6 +36,8 @@ int main(void)
 	card10_init();
 	card10_diag();
 
+    cdcacm_init();
+
 	printf("Initializing dispatcher ...\n");
 	api_dispatcher_init();
 

epicardium/meson.build

@@ -48,7 +48,8 @@ api_dispatcher_lib = static_library(
 elf = executable(
   name + '.elf',
   'main.c',
-  dependencies: [libcard10, max32665_startup_core0],
+  'cdcacm.c',
+  dependencies: [libcard10, max32665_startup_core0, maxusb],
   link_with: api_dispatcher_lib,
   link_whole: [max32665_startup_core0_lib, board_card10_lib],
   link_args: [