test-display/main.c

   1 /*
   2  *      Test Gadget
   3  *
   4  *      (c) 2020 Martin Mareš <mj@ucw.cz>
   5  */
   6
   7 #include "util.h"
   8
   9 #include <libopencm3/cm3/cortex.h>
  10 #include <libopencm3/cm3/nvic.h>
  11 #include <libopencm3/cm3/systick.h>
  12 #include <libopencm3/cm3/scb.h>
  13 #include <libopencm3/stm32/rcc.h>
  14 #include <libopencm3/stm32/desig.h>
  15 #include <libopencm3/stm32/gpio.h>
  16 #include <libopencm3/stm32/usart.h>
  17 #include <libopencm3/stm32/i2c.h>
  18 #include <libopencm3/usb/dfu.h>
  19 #include <libopencm3/usb/usbd.h>
  20
  21 #include <string.h>
  22
  23 /*** Hardware init ***/
  24
  25 static void clock_init(void)
  26 {
  27         rcc_clock_setup_in_hse_8mhz_out_72mhz();
  28
  29         rcc_periph_clock_enable(RCC_GPIOA);
  30         rcc_periph_clock_enable(RCC_GPIOB);
  31         rcc_periph_clock_enable(RCC_GPIOC);
  32         rcc_periph_clock_enable(RCC_I2C1);
  33         rcc_periph_clock_enable(RCC_USART1);
  34         rcc_periph_clock_enable(RCC_USB);
  35
  36         rcc_periph_reset_pulse(RST_GPIOA);
  37         rcc_periph_reset_pulse(RST_GPIOB);
  38         rcc_periph_reset_pulse(RST_GPIOC);
  39         rcc_periph_reset_pulse(RST_I2C1);
  40         rcc_periph_reset_pulse(RST_USART1);
  41         rcc_periph_reset_pulse(RST_USB);
  42 }
  43
  44 static void gpio_init(void)
  45 {
  46         // PA9 = TXD1 for debugging console
  47         // PA10 = RXD1 for debugging console
  48         gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_PUSHPULL, GPIO9);
  49         gpio_set_mode(GPIOA, GPIO_MODE_INPUT, GPIO_CNF_INPUT_FLOAT, GPIO10);
  50
  51         // PC13 = BluePill LED
  52         gpio_set_mode(GPIOC, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_PUSHPULL, GPIO13);
  53         gpio_clear(GPIOC, GPIO13);
  54
  55         // PB7 = SDA for display controller
  56         // PB6 = SCL for display controller
  57         gpio_set_mode(GPIOB, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_ALTFN_OPENDRAIN, GPIO6 | GPIO7);
  58 }
  59
  60 static void usart_init(void)
  61 {
  62         usart_set_baudrate(USART1, 115200);
  63         usart_set_databits(USART1, 8);
  64         usart_set_stopbits(USART1, USART_STOPBITS_1);
  65         usart_set_mode(USART1, USART_MODE_TX);
  66         usart_set_parity(USART1, USART_PARITY_NONE);
  67         usart_set_flow_control(USART1, USART_FLOWCONTROL_NONE);
  68
  69         usart_enable(USART1);
  70 }
  71
  72 /*** System ticks ***/
  73
  74 static volatile u32 ms_ticks;
  75
  76 void sys_tick_handler(void)
  77 {
  78         ms_ticks++;
  79 }
  80
  81 static void tick_init(void)
  82 {
  83         systick_set_frequency(1000, CPU_CLOCK_MHZ * 1000000);
  84         systick_counter_enable();
  85         systick_interrupt_enable();
  86 }
  87
  88 static void delay_ms(uint ms)
  89 {
  90         u32 start_ticks = ms_ticks;
  91         while (ms_ticks - start_ticks < ms)
  92                 ;
  93 }
  94
  95 /*** Display ***/
  96
  97 /*
  98  *      Display digits:
  99  *
 100  *                 ---- 20 ----
 101  *               |              |
 102  *               |              |
 103  *              40              10
 104  *               |              |
 105  *               |              |
 106  *                 ---- 80 ----
 107  *               |              |
 108  *               |              |
 109  *              08              02
 110  *               |              |
 111  *               |              |
 112  *                 ---- 04 ----
 113  *                                      (01)
 114  */
 115
 116
 117 static void display_init(void)
 118 {
 119         debug_puts("I2C init\n");
 120         i2c_peripheral_disable(I2C1);
 121         i2c_set_speed(I2C1, i2c_speed_sm_100k, CPU_CLOCK_MHZ);
 122         i2c_peripheral_enable(I2C1);
 123
 124         debug_puts("I2C transfer\n");
 125
 126         // byte disp[] = { 0x7f, 0x12, 0xb6, 0xd2 };
 127         byte disp[] = { 0xff, 0xff, 0xff, 0xff };
 128         byte cmds[] = { 0x00, 0x47, 0, 0, 0, 0 };
 129         cmds[2] = (disp[0] & 0xf0) | (disp[2] >> 4);
 130         cmds[3] = (disp[1] & 0xf0) | (disp[3] >> 4);
 131         cmds[4] = (disp[2] & 0x0f) | (disp[0] << 4);
 132         cmds[5] = (disp[3] & 0x0f) | (disp[1] << 4);
 133         i2c_transfer7(I2C1, 0x70/2, (byte *) cmds, sizeof(cmds), NULL, 0);
 134
 135         debug_puts("I2C done\n");
 136 }
 137
 138 /*** USB ***/
 139
 140 static usbd_device *usbd_dev;
 141
 142 enum usb_string {
 143         STR_MANUFACTURER = 1,
 144         STR_PRODUCT,
 145         STR_SERIAL,
 146 };
 147
 148 static char usb_serial_number[13];
 149
 150 static const char *usb_strings[] = {
 151         "United Computer Wizards",
 152         "Test Gadget",
 153         usb_serial_number,
 154 };
 155
 156 static const struct usb_device_descriptor device = {
 157         .bLength = USB_DT_DEVICE_SIZE,
 158         .bDescriptorType = USB_DT_DEVICE,
 159         .bcdUSB = 0x0200,
 160         .bDeviceClass = 0xFF,
 161         .bDeviceSubClass = 0,
 162         .bDeviceProtocol = 0,
 163         .bMaxPacketSize0 = 64,
 164         .idVendor = 0x4242,
 165         .idProduct = 0x0007,
 166         .bcdDevice = 0x0000,
 167         .iManufacturer = STR_MANUFACTURER,
 168         .iProduct = STR_PRODUCT,
 169         .iSerialNumber = STR_SERIAL,
 170         .bNumConfigurations = 1,
 171 };
 172
 173 static const struct usb_endpoint_descriptor endpoints[] = {{
 174         // Bulk end-point for sending values to DMX
 175         .bLength = USB_DT_ENDPOINT_SIZE,
 176         .bDescriptorType = USB_DT_ENDPOINT,
 177         .bEndpointAddress = 0x01,
 178         .bmAttributes = USB_ENDPOINT_ATTR_BULK,
 179         .wMaxPacketSize = 64,
 180         .bInterval = 1,
 181 }};
 182
 183 static const struct usb_interface_descriptor iface = {
 184         .bLength = USB_DT_INTERFACE_SIZE,
 185         .bDescriptorType = USB_DT_INTERFACE,
 186         .bInterfaceNumber = 0,
 187         .bAlternateSetting = 0,
 188         .bNumEndpoints = 1,
 189         .bInterfaceClass = 0xFF,
 190         .bInterfaceSubClass = 0,
 191         .bInterfaceProtocol = 0,
 192         .iInterface = 0,
 193         .endpoint = endpoints,
 194 };
 195
 196 static const struct usb_dfu_descriptor dfu_function = {
 197         .bLength = sizeof(struct usb_dfu_descriptor),
 198         .bDescriptorType = DFU_FUNCTIONAL,
 199         .bmAttributes = USB_DFU_CAN_DOWNLOAD | USB_DFU_WILL_DETACH,
 200         .wDetachTimeout = 255,
 201         .wTransferSize = 1024,
 202         .bcdDFUVersion = 0x0100,
 203 };
 204
 205 static const struct usb_interface_descriptor dfu_iface = {
 206         .bLength = USB_DT_INTERFACE_SIZE,
 207         .bDescriptorType = USB_DT_INTERFACE,
 208         .bInterfaceNumber = 1,
 209         .bAlternateSetting = 0,
 210         .bNumEndpoints = 0,
 211         .bInterfaceClass = 0xFE,
 212         .bInterfaceSubClass = 1,
 213         .bInterfaceProtocol = 1,
 214         .iInterface = 0,
 215
 216         .extra = &dfu_function,
 217         .extralen = sizeof(dfu_function),
 218 };
 219
 220 static const struct usb_interface ifaces[] = {{
 221         .num_altsetting = 1,
 222         .altsetting = &iface,
 223 }, {
 224         .num_altsetting = 1,
 225         .altsetting = &dfu_iface,
 226 }};
 227
 228 static const struct usb_config_descriptor config = {
 229         .bLength = USB_DT_CONFIGURATION_SIZE,
 230         .bDescriptorType = USB_DT_CONFIGURATION,
 231         .wTotalLength = 0,
 232         .bNumInterfaces = 2,
 233         .bConfigurationValue = 1,
 234         .iConfiguration = 0,
 235         .bmAttributes = 0x80,
 236         .bMaxPower = 50,        // multiplied by 2 mA
 237         .interface = ifaces,
 238 };
 239
 240 static byte usb_configured;
 241 static uint8_t usbd_control_buffer[64];
 242
 243 static void dfu_detach_complete(usbd_device *dev UNUSED, struct usb_setup_data *req UNUSED)
 244 {
 245         // Reset to bootloader, which implements the rest of DFU
 246         debug_printf("Switching to DFU\n");
 247         debug_flush();
 248         scb_reset_core();
 249 }
 250
 251 static enum usbd_request_return_codes dfu_control_cb(usbd_device *dev UNUSED,
 252         struct usb_setup_data *req,
 253         uint8_t **buf UNUSED,
 254         uint16_t *len UNUSED,
 255         void (**complete)(usbd_device *dev, struct usb_setup_data *req))
 256 {
 257         if (req->bmRequestType != 0x21 || req->bRequest != DFU_DETACH)
 258                 return USBD_REQ_NOTSUPP;
 259
 260         *complete = dfu_detach_complete;
 261         return USBD_REQ_HANDLED;
 262 }
 263
 264 # if 0
 265 static void ep01_cb(usbd_device *dev, uint8_t ep UNUSED)
 266 {
 267         // We received a frame from the USB host
 268         uint len = usbd_ep_read_packet(dev, 0x01, dmx_next_packet, DMX_MAX_PACKET_SIZE);
 269         debug_printf("USB: Host sent %u bytes\n", len);
 270 }
 271 #endif
 272
 273 static void set_config_cb(usbd_device *dev, uint16_t wValue UNUSED)
 274 {
 275         usbd_register_control_callback(
 276                 dev,
 277                 USB_REQ_TYPE_CLASS | USB_REQ_TYPE_INTERFACE,
 278                 USB_REQ_TYPE_TYPE | USB_REQ_TYPE_RECIPIENT,
 279                 dfu_control_cb);
 280         // usbd_ep_setup(dev, 0x01, USB_ENDPOINT_ATTR_BULK, 64, ep01_cb);
 281         usb_configured = 1;
 282 }
 283
 284 static void reset_cb(void)
 285 {
 286         debug_printf("USB: Reset\n");
 287         usb_configured = 0;
 288 }
 289
 290 static volatile bool usb_event_pending;
 291
 292 void usb_lp_can_rx0_isr(void)
 293 {
 294         /*
 295          *  We handle USB in the main loop to avoid race conditions between
 296          *  USB interrupts and other code. However, we need an interrupt to
 297          *  up the main loop from sleep.
 298          *
 299          *  We set up only the low-priority ISR, because high-priority ISR handles
 300          *  only double-buffered bulk transfers and isochronous transfers.
 301          */
 302         nvic_disable_irq(NVIC_USB_LP_CAN_RX0_IRQ);
 303         usb_event_pending = 1;
 304 }
 305
 306 static void usb_init(void)
 307 {
 308         // Simulate USB disconnect
 309         gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_OPENDRAIN, GPIO11 | GPIO12);
 310         gpio_clear(GPIOA, GPIO11 | GPIO12);
 311         delay_ms(100);
 312
 313         usbd_dev = usbd_init(
 314                 &st_usbfs_v1_usb_driver,
 315                 &device,
 316                 &config,
 317                 usb_strings,
 318                 ARRAY_SIZE(usb_strings),
 319                 usbd_control_buffer,
 320                 sizeof(usbd_control_buffer)
 321         );
 322         usbd_register_reset_callback(usbd_dev, reset_cb);
 323         usbd_register_set_config_callback(usbd_dev, set_config_cb);
 324         usb_event_pending = 1;
 325 }
 326
 327 /*** Main ***/
 328
 329 int main(void)
 330 {
 331         clock_init();
 332         gpio_init();
 333         tick_init();
 334         usart_init();
 335         desig_get_unique_id_as_dfu(usb_serial_number);
 336
 337         debug_printf("Hello, world!\n");
 338
 339         usb_init();
 340         display_init();
 341
 342         u32 last_blink = 0;
 343
 344         for (;;) {
 345                 if (ms_ticks - last_blink >= 100) {
 346                         debug_led_toggle();
 347                         last_blink = ms_ticks;
 348                 }
 349
 350                 if (usb_event_pending) {
 351                         usbd_poll(usbd_dev);
 352                         usb_event_pending = 0;
 353                         nvic_clear_pending_irq(NVIC_USB_LP_CAN_RX0_IRQ);
 354                         nvic_enable_irq(NVIC_USB_LP_CAN_RX0_IRQ);
 355                 }
 356
 357                 wait_for_interrupt();
 358         }
 359
 360         return 0;
 361 }