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, rcc_apb1_frequency / 1000000);
 122         i2c_peripheral_enable(I2C1);
 123
 124         debug_puts("I2C transfer\n");
 125
 126         // byte disp[] = { 0xb6, 0xb6, 0xb6, 0xb6 };
 127         // byte disp[] = { 0x7f, 0x12, 0xbc, 0xb6 };
 128         // byte disp[] = { 0xff, 0xff, 0xff, 0xff };
 129         byte disp[] = { 0x80, 0x80, 0x80, 0xff };
 130         byte cmds[] = { 0x00, 0x47, 0, 0, 0, 0 };
 131         cmds[2] = (disp[0] & 0xf0) | (disp[2] >> 4);
 132         cmds[3] = (disp[1] & 0xf0) | (disp[3] >> 4);
 133         cmds[4] = (disp[2] & 0x0f) | (disp[0] << 4);
 134         cmds[5] = (disp[3] & 0x0f) | (disp[1] << 4);
 135         i2c_transfer7(I2C1, 0x70/2, (byte *) cmds, sizeof(cmds), NULL, 0);
 136
 137         debug_puts("I2C done\n");
 138 }
 139
 140 static void display_test(void)
 141 {
 142         static byte mode;
 143
 144         byte cmds[] = { 0x00, mode ? 0x77 : 0x77 };
 145         i2c_transfer7(I2C1, 0x70/2, (byte *) cmds, sizeof(cmds), NULL, 0);
 146
 147         mode = !mode;
 148 }
 149
 150 /*** USB ***/
 151
 152 static usbd_device *usbd_dev;
 153
 154 enum usb_string {
 155         STR_MANUFACTURER = 1,
 156         STR_PRODUCT,
 157         STR_SERIAL,
 158 };
 159
 160 static char usb_serial_number[13];
 161
 162 static const char *usb_strings[] = {
 163         "United Computer Wizards",
 164         "Test Gadget",
 165         usb_serial_number,
 166 };
 167
 168 static const struct usb_device_descriptor device = {
 169         .bLength = USB_DT_DEVICE_SIZE,
 170         .bDescriptorType = USB_DT_DEVICE,
 171         .bcdUSB = 0x0200,
 172         .bDeviceClass = 0xFF,
 173         .bDeviceSubClass = 0,
 174         .bDeviceProtocol = 0,
 175         .bMaxPacketSize0 = 64,
 176         .idVendor = 0x4242,
 177         .idProduct = 0x0007,
 178         .bcdDevice = 0x0000,
 179         .iManufacturer = STR_MANUFACTURER,
 180         .iProduct = STR_PRODUCT,
 181         .iSerialNumber = STR_SERIAL,
 182         .bNumConfigurations = 1,
 183 };
 184
 185 static const struct usb_endpoint_descriptor endpoints[] = {{
 186         // Bulk end-point for sending values to DMX
 187         .bLength = USB_DT_ENDPOINT_SIZE,
 188         .bDescriptorType = USB_DT_ENDPOINT,
 189         .bEndpointAddress = 0x01,
 190         .bmAttributes = USB_ENDPOINT_ATTR_BULK,
 191         .wMaxPacketSize = 64,
 192         .bInterval = 1,
 193 }};
 194
 195 static const struct usb_interface_descriptor iface = {
 196         .bLength = USB_DT_INTERFACE_SIZE,
 197         .bDescriptorType = USB_DT_INTERFACE,
 198         .bInterfaceNumber = 0,
 199         .bAlternateSetting = 0,
 200         .bNumEndpoints = 1,
 201         .bInterfaceClass = 0xFF,
 202         .bInterfaceSubClass = 0,
 203         .bInterfaceProtocol = 0,
 204         .iInterface = 0,
 205         .endpoint = endpoints,
 206 };
 207
 208 static const struct usb_dfu_descriptor dfu_function = {
 209         .bLength = sizeof(struct usb_dfu_descriptor),
 210         .bDescriptorType = DFU_FUNCTIONAL,
 211         .bmAttributes = USB_DFU_CAN_DOWNLOAD | USB_DFU_WILL_DETACH,
 212         .wDetachTimeout = 255,
 213         .wTransferSize = 1024,
 214         .bcdDFUVersion = 0x0100,
 215 };
 216
 217 static const struct usb_interface_descriptor dfu_iface = {
 218         .bLength = USB_DT_INTERFACE_SIZE,
 219         .bDescriptorType = USB_DT_INTERFACE,
 220         .bInterfaceNumber = 1,
 221         .bAlternateSetting = 0,
 222         .bNumEndpoints = 0,
 223         .bInterfaceClass = 0xFE,
 224         .bInterfaceSubClass = 1,
 225         .bInterfaceProtocol = 1,
 226         .iInterface = 0,
 227
 228         .extra = &dfu_function,
 229         .extralen = sizeof(dfu_function),
 230 };
 231
 232 static const struct usb_interface ifaces[] = {{
 233         .num_altsetting = 1,
 234         .altsetting = &iface,
 235 }, {
 236         .num_altsetting = 1,
 237         .altsetting = &dfu_iface,
 238 }};
 239
 240 static const struct usb_config_descriptor config = {
 241         .bLength = USB_DT_CONFIGURATION_SIZE,
 242         .bDescriptorType = USB_DT_CONFIGURATION,
 243         .wTotalLength = 0,
 244         .bNumInterfaces = 2,
 245         .bConfigurationValue = 1,
 246         .iConfiguration = 0,
 247         .bmAttributes = 0x80,
 248         .bMaxPower = 50,        // multiplied by 2 mA
 249         .interface = ifaces,
 250 };
 251
 252 static byte usb_configured;
 253 static uint8_t usbd_control_buffer[64];
 254
 255 static void dfu_detach_complete(usbd_device *dev UNUSED, struct usb_setup_data *req UNUSED)
 256 {
 257         // Reset to bootloader, which implements the rest of DFU
 258         debug_printf("Switching to DFU\n");
 259         debug_flush();
 260         scb_reset_core();
 261 }
 262
 263 static enum usbd_request_return_codes dfu_control_cb(usbd_device *dev UNUSED,
 264         struct usb_setup_data *req,
 265         uint8_t **buf UNUSED,
 266         uint16_t *len UNUSED,
 267         void (**complete)(usbd_device *dev, struct usb_setup_data *req))
 268 {
 269         if (req->bmRequestType != 0x21 || req->bRequest != DFU_DETACH)
 270                 return USBD_REQ_NOTSUPP;
 271
 272         *complete = dfu_detach_complete;
 273         return USBD_REQ_HANDLED;
 274 }
 275
 276 # if 0
 277 static void ep01_cb(usbd_device *dev, uint8_t ep UNUSED)
 278 {
 279         // We received a frame from the USB host
 280         uint len = usbd_ep_read_packet(dev, 0x01, dmx_next_packet, DMX_MAX_PACKET_SIZE);
 281         debug_printf("USB: Host sent %u bytes\n", len);
 282 }
 283 #endif
 284
 285 static void set_config_cb(usbd_device *dev, uint16_t wValue UNUSED)
 286 {
 287         usbd_register_control_callback(
 288                 dev,
 289                 USB_REQ_TYPE_CLASS | USB_REQ_TYPE_INTERFACE,
 290                 USB_REQ_TYPE_TYPE | USB_REQ_TYPE_RECIPIENT,
 291                 dfu_control_cb);
 292         // usbd_ep_setup(dev, 0x01, USB_ENDPOINT_ATTR_BULK, 64, ep01_cb);
 293         usb_configured = 1;
 294 }
 295
 296 static void reset_cb(void)
 297 {
 298         debug_printf("USB: Reset\n");
 299         usb_configured = 0;
 300 }
 301
 302 static volatile bool usb_event_pending;
 303
 304 void usb_lp_can_rx0_isr(void)
 305 {
 306         /*
 307          *  We handle USB in the main loop to avoid race conditions between
 308          *  USB interrupts and other code. However, we need an interrupt to
 309          *  up the main loop from sleep.
 310          *
 311          *  We set up only the low-priority ISR, because high-priority ISR handles
 312          *  only double-buffered bulk transfers and isochronous transfers.
 313          */
 314         nvic_disable_irq(NVIC_USB_LP_CAN_RX0_IRQ);
 315         usb_event_pending = 1;
 316 }
 317
 318 static void usb_init(void)
 319 {
 320         // Simulate USB disconnect
 321         gpio_set_mode(GPIOA, GPIO_MODE_OUTPUT_50_MHZ, GPIO_CNF_OUTPUT_OPENDRAIN, GPIO11 | GPIO12);
 322         gpio_clear(GPIOA, GPIO11 | GPIO12);
 323         delay_ms(100);
 324
 325         usbd_dev = usbd_init(
 326                 &st_usbfs_v1_usb_driver,
 327                 &device,
 328                 &config,
 329                 usb_strings,
 330                 ARRAY_SIZE(usb_strings),
 331                 usbd_control_buffer,
 332                 sizeof(usbd_control_buffer)
 333         );
 334         usbd_register_reset_callback(usbd_dev, reset_cb);
 335         usbd_register_set_config_callback(usbd_dev, set_config_cb);
 336         usb_event_pending = 1;
 337 }
 338
 339 /*** Main ***/
 340
 341 int main(void)
 342 {
 343         clock_init();
 344         gpio_init();
 345         tick_init();
 346         usart_init();
 347         desig_get_unique_id_as_dfu(usb_serial_number);
 348
 349         debug_printf("Hello, world!\n");
 350
 351         usb_init();
 352         display_init();
 353
 354         u32 last_blink = 0;
 355
 356         for (;;) {
 357                 if (ms_ticks - last_blink >= 100) {
 358                         debug_led_toggle();
 359                         last_blink = ms_ticks;
 360                         display_test();
 361                 }
 362
 363                 if (usb_event_pending) {
 364                         usbd_poll(usbd_dev);
 365                         usb_event_pending = 0;
 366                         nvic_clear_pending_irq(NVIC_USB_LP_CAN_RX0_IRQ);
 367                         nvic_enable_irq(NVIC_USB_LP_CAN_RX0_IRQ);
 368                 }
 369
 370                 wait_for_interrupt();
 371         }
 372
 373         return 0;
 374 }