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 static byte disp[4];
 117 static byte ctrl = 0x77;
 118
 119 static void display_update(void)
 120 {
 121         byte cmds[6];
 122         cmds[0] = 0;
 123         cmds[1] = ctrl;
 124         cmds[2] = (disp[0] & 0xf0) | (disp[2] >> 4);
 125         cmds[3] = (disp[1] & 0xf0) | (disp[3] >> 4);
 126         cmds[4] = (disp[2] & 0x0f) | (disp[0] << 4);
 127         cmds[5] = (disp[3] & 0x0f) | (disp[1] << 4);
 128
 129         debug_puts("I2C transfer\n");
 130         i2c_transfer7(I2C1, 0x70/2, (byte *) cmds, sizeof(cmds), NULL, 0);
 131         debug_puts("I2C done\n");
 132 }
 133
 134 static void display_init(void)
 135 {
 136         debug_puts("I2C init\n");
 137         i2c_peripheral_disable(I2C1);
 138         i2c_set_speed(I2C1, i2c_speed_sm_100k, rcc_apb1_frequency / 1000000);
 139         i2c_peripheral_enable(I2C1);
 140
 141         disp[0] = 0x7f;
 142         disp[1] = 0x12;
 143         disp[2] = 0xbc;
 144         disp[3] = 0xb6;
 145         display_update();
 146 }
 147
 148 static void display_test(void)
 149 {
 150         static byte mode;
 151
 152         disp[0] ^= 0x01;
 153         display_update();
 154
 155 #if 0
 156         byte cmds[] = { 0x00, mode ? 0x77 : 0x77 };
 157         i2c_transfer7(I2C1, 0x70/2, (byte *) cmds, sizeof(cmds), NULL, 0);
 158 #endif
 159
 160 #if 0
 161         byte disp[] = { 0xff, 0xff, mode ? 0xff : 0x00, mode ? 0xff : 0xff };
 162         byte cmds[] = { 0x00, 0x77, 0, 0, 0, 0 };
 163         cmds[2] = (disp[0] & 0xf0) | (disp[2] >> 4);
 164         cmds[3] = (disp[1] & 0xf0) | (disp[3] >> 4);
 165         cmds[4] = (disp[2] & 0x0f) | (disp[0] << 4);
 166         cmds[5] = (disp[3] & 0x0f) | (disp[1] << 4);
 167         i2c_transfer7(I2C1, 0x70/2, (byte *) cmds, sizeof(cmds), NULL, 0);
 168 #endif
 169
 170         mode = !mode;
 171 }
 172
 173 /*** USB ***/
 174
 175 static usbd_device *usbd_dev;
 176
 177 enum usb_string {
 178         STR_MANUFACTURER = 1,
 179         STR_PRODUCT,
 180         STR_SERIAL,
 181 };
 182
 183 static char usb_serial_number[13];
 184
 185 static const char *usb_strings[] = {
 186         "United Computer Wizards",
 187         "Test Gadget",
 188         usb_serial_number,
 189 };
 190
 191 static const struct usb_device_descriptor device = {
 192         .bLength = USB_DT_DEVICE_SIZE,
 193         .bDescriptorType = USB_DT_DEVICE,
 194         .bcdUSB = 0x0200,
 195         .bDeviceClass = 0xFF,
 196         .bDeviceSubClass = 0,
 197         .bDeviceProtocol = 0,
 198         .bMaxPacketSize0 = 64,
 199         .idVendor = 0x4242,
 200         .idProduct = 0x0007,
 201         .bcdDevice = 0x0000,
 202         .iManufacturer = STR_MANUFACTURER,
 203         .iProduct = STR_PRODUCT,
 204         .iSerialNumber = STR_SERIAL,
 205         .bNumConfigurations = 1,
 206 };
 207
 208 static const struct usb_endpoint_descriptor endpoints[] = {{
 209         // Bulk end-point for sending values to DMX
 210         .bLength = USB_DT_ENDPOINT_SIZE,
 211         .bDescriptorType = USB_DT_ENDPOINT,
 212         .bEndpointAddress = 0x01,
 213         .bmAttributes = USB_ENDPOINT_ATTR_BULK,
 214         .wMaxPacketSize = 64,
 215         .bInterval = 1,
 216 }};
 217
 218 static const struct usb_interface_descriptor iface = {
 219         .bLength = USB_DT_INTERFACE_SIZE,
 220         .bDescriptorType = USB_DT_INTERFACE,
 221         .bInterfaceNumber = 0,
 222         .bAlternateSetting = 0,
 223         .bNumEndpoints = 1,
 224         .bInterfaceClass = 0xFF,
 225         .bInterfaceSubClass = 0,
 226         .bInterfaceProtocol = 0,
 227         .iInterface = 0,
 228         .endpoint = endpoints,
 229 };
 230
 231 static const struct usb_dfu_descriptor dfu_function = {
 232         .bLength = sizeof(struct usb_dfu_descriptor),
 233         .bDescriptorType = DFU_FUNCTIONAL,
 234         .bmAttributes = USB_DFU_CAN_DOWNLOAD | USB_DFU_WILL_DETACH,
 235         .wDetachTimeout = 255,
 236         .wTransferSize = 1024,
 237         .bcdDFUVersion = 0x0100,
 238 };
 239
 240 static const struct usb_interface_descriptor dfu_iface = {
 241         .bLength = USB_DT_INTERFACE_SIZE,
 242         .bDescriptorType = USB_DT_INTERFACE,
 243         .bInterfaceNumber = 1,
 244         .bAlternateSetting = 0,
 245         .bNumEndpoints = 0,
 246         .bInterfaceClass = 0xFE,
 247         .bInterfaceSubClass = 1,
 248         .bInterfaceProtocol = 1,
 249         .iInterface = 0,
 250
 251         .extra = &dfu_function,
 252         .extralen = sizeof(dfu_function),
 253 };
 254
 255 static const struct usb_interface ifaces[] = {{
 256         .num_altsetting = 1,
 257         .altsetting = &iface,
 258 }, {
 259         .num_altsetting = 1,
 260         .altsetting = &dfu_iface,
 261 }};
 262
 263 static const struct usb_config_descriptor config = {
 264         .bLength = USB_DT_CONFIGURATION_SIZE,
 265         .bDescriptorType = USB_DT_CONFIGURATION,
 266         .wTotalLength = 0,
 267         .bNumInterfaces = 2,
 268         .bConfigurationValue = 1,
 269         .iConfiguration = 0,
 270         .bmAttributes = 0x80,
 271         .bMaxPower = 50,        // multiplied by 2 mA
 272         .interface = ifaces,
 273 };
 274
 275 static byte usb_configured;
 276 static uint8_t usbd_control_buffer[64];
 277
 278 static void dfu_detach_complete(usbd_device *dev UNUSED, struct usb_setup_data *req UNUSED)
 279 {
 280         // Reset to bootloader, which implements the rest of DFU
 281         debug_printf("Switching to DFU\n");
 282         debug_flush();
 283         scb_reset_core();
 284 }
 285
 286 static enum usbd_request_return_codes dfu_control_cb(usbd_device *dev UNUSED,
 287         struct usb_setup_data *req,
 288         uint8_t **buf UNUSED,
 289         uint16_t *len UNUSED,
 290         void (**complete)(usbd_device *dev, struct usb_setup_data *req))
 291 {
 292         if (req->bmRequestType != 0x21 || req->bRequest != DFU_DETACH)
 293                 return USBD_REQ_NOTSUPP;
 294
 295         *complete = dfu_detach_complete;
 296         return USBD_REQ_HANDLED;
 297 }
 298
 299 # if 0
 300 static void ep01_cb(usbd_device *dev, uint8_t ep UNUSED)
 301 {
 302         // We received a frame from the USB host
 303         uint len = usbd_ep_read_packet(dev, 0x01, dmx_next_packet, DMX_MAX_PACKET_SIZE);
 304         debug_printf("USB: Host sent %u bytes\n", len);
 305 }
 306 #endif
 307
 308 static void set_config_cb(usbd_device *dev, uint16_t wValue UNUSED)
 309 {
 310         usbd_register_control_callback(
 311                 dev,
 312                 USB_REQ_TYPE_CLASS | USB_REQ_TYPE_INTERFACE,
 313                 USB_REQ_TYPE_TYPE | USB_REQ_TYPE_RECIPIENT,
 314                 dfu_control_cb);
 315         // usbd_ep_setup(dev, 0x01, USB_ENDPOINT_ATTR_BULK, 64, ep01_cb);
 316         usb_configured = 1;
 317 }
 318
 319 static void reset_cb(void)
 320 {
 321         debug_printf("USB: Reset\n");
 322         usb_configured = 0;
 323 }
 324
 325 static volatile bool usb_event_pending;
 326
 327 void usb_lp_can_rx0_isr(void)
 328 {
 329         /*
 330          *  We handle USB in the main loop to avoid race conditions between
 331          *  USB interrupts and other code. However, we need an interrupt to
 332          *  up the main loop from sleep.
 333          *
 334          *  We set up only the low-priority ISR, because high-priority ISR handles
 335          *  only double-buffered bulk transfers and isochronous transfers.
 336          */
 337         nvic_disable_irq(NVIC_USB_LP_CAN_RX0_IRQ);
 338         usb_event_pending = 1;
 339 }
 340
 341 static void usb_init(void)
 342 {
 343         // Simulate USB disconnect
 344         gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_OPENDRAIN, GPIO11 | GPIO12);
 345         gpio_clear(GPIOA, GPIO11 | GPIO12);
 346         delay_ms(100);
 347
 348         usbd_dev = usbd_init(
 349                 &st_usbfs_v1_usb_driver,
 350                 &device,
 351                 &config,
 352                 usb_strings,
 353                 ARRAY_SIZE(usb_strings),
 354                 usbd_control_buffer,
 355                 sizeof(usbd_control_buffer)
 356         );
 357         usbd_register_reset_callback(usbd_dev, reset_cb);
 358         usbd_register_set_config_callback(usbd_dev, set_config_cb);
 359         usb_event_pending = 1;
 360 }
 361
 362 /*** Main ***/
 363
 364 int main(void)
 365 {
 366         clock_init();
 367         gpio_init();
 368         tick_init();
 369         usart_init();
 370         desig_get_unique_id_as_dfu(usb_serial_number);
 371
 372         debug_printf("Hello, world!\n");
 373
 374         usb_init();
 375         display_init();
 376
 377         u32 last_blink = 0;
 378
 379         for (;;) {
 380                 if (ms_ticks - last_blink >= 500) {
 381                         debug_led_toggle();
 382                         last_blink = ms_ticks;
 383                         display_test();
 384                 }
 385
 386                 if (usb_event_pending) {
 387                         usbd_poll(usbd_dev);
 388                         usb_event_pending = 0;
 389                         nvic_clear_pending_irq(NVIC_USB_LP_CAN_RX0_IRQ);
 390                         nvic_enable_irq(NVIC_USB_LP_CAN_RX0_IRQ);
 391                 }
 392
 393                 wait_for_interrupt();
 394         }
 395
 396         return 0;
 397 }