usbser.c

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#include "usbser.h"

#include "cfg/cfg_usbser.h"

#define LOG_LEVEL  USB_SERIAL_LOG_LEVEL
#define LOG_FORMAT USB_SERIAL_LOG_FORMAT

#include <cfg/log.h>
#include <cfg/debug.h>
#include <cfg/macros.h>

#include <cfg/compiler.h>
#include <cfg/module.h>

#include <cpu/irq.h> /* IRQ_DISABLE / IRQ_ENABLE */
#include <cpu/power.h> /* cpu_relax() */

#include <drv/usb.h>
#include <drv/usb_endpoint.h>

#include <string.h> /* memcpy() */


#define USB_SERIAL_INTERFACES   1
#define USB_SERIAL_ENDPOINTS    3

#define USB_STRING_MANUFACTURER 1
#define USB_STRING_PRODUCT  2
#define USB_STRING_SERIAL   3

static UsbDeviceDesc usb_serial_device_descriptor =
{
    .bLength = sizeof(usb_serial_device_descriptor),
    .bDescriptorType = USB_DT_DEVICE,
    .bcdUSB = 0x110,
    .bDeviceClass = USB_CLASS_COMM,
    .bDeviceSubClass = 0,
    .bDeviceProtocol = 0,
    .idVendor = USB_SERIAL_VENDOR_ID,
    .idProduct = USB_SERIAL_PRODUCT_ID,
    .bcdDevice = 0,
    .iManufacturer = USB_STRING_MANUFACTURER,
    .iProduct = USB_STRING_PRODUCT,
    .iSerialNumber = USB_STRING_SERIAL,
    .bNumConfigurations = 1,
};

static const UsbConfigDesc usb_serial_config_descriptor =
{
    .bLength = sizeof(usb_serial_config_descriptor),
    .bDescriptorType = USB_DT_CONFIG,
    .bNumInterfaces = USB_SERIAL_INTERFACES,
    .bConfigurationValue = 1,
    .iConfiguration = 0,
    .bmAttributes = USB_CONFIG_ATT_ONE,
    .bMaxPower = 50, /* 100 mA */
};

static const UsbInterfaceDesc usb_serial_interface_descriptor =
{
    .bLength = sizeof(usb_serial_interface_descriptor),
    .bDescriptorType = USB_DT_INTERFACE,
    .bInterfaceNumber = 0,
    .bAlternateSetting = 0,
    .bNumEndpoints = USB_SERIAL_ENDPOINTS,
    .bInterfaceClass = 0xff,
    .bInterfaceSubClass = 0,
    .bInterfaceProtocol = 0,
    .iInterface = 0,
};

static const UsbEndpointDesc usb_serial_ep_report_descriptor =
{
    .bLength = sizeof(usb_serial_ep_report_descriptor),
    .bDescriptorType = USB_DT_ENDPOINT,
    .bEndpointAddress = USB_DIR_IN | USB_SERIAL_EP_REPORT,
    .bmAttributes = USB_ENDPOINT_XFER_INT,
    .wMaxPacketSize = usb_cpu_to_le16((uint16_t)8),
    .bInterval = 1,
};

static const UsbEndpointDesc usb_serial_ep_in_descriptor =
{
    .bLength = sizeof(usb_serial_ep_in_descriptor),
    .bDescriptorType = USB_DT_ENDPOINT,
    .bEndpointAddress = USB_DIR_IN | USB_SERIAL_EP_IN,
    .bmAttributes = USB_ENDPOINT_XFER_BULK,
    .wMaxPacketSize = usb_cpu_to_le16((uint16_t)64),
    .bInterval = 0,
};

static const UsbEndpointDesc usb_serial_ep_out_descriptor =
{
    .bLength = sizeof(usb_serial_ep_in_descriptor),
    .bDescriptorType = USB_DT_ENDPOINT,
    .bEndpointAddress = USB_DIR_OUT | USB_SERIAL_EP_OUT,
    .bmAttributes = USB_ENDPOINT_XFER_BULK,
    .wMaxPacketSize = usb_cpu_to_le16((uint16_t)64),
    .bInterval = 0,
};

static const UsbDescHeader *usb_serial_config[] =
{
    (const UsbDescHeader *)&usb_serial_config_descriptor,
    (const UsbDescHeader *)&usb_serial_interface_descriptor,
    (const UsbDescHeader *)&usb_serial_ep_report_descriptor,
    (const UsbDescHeader *)&usb_serial_ep_in_descriptor,
    (const UsbDescHeader *)&usb_serial_ep_out_descriptor,
    NULL,
};

static const DEFINE_USB_STRING(language_str, "\x09\x04"); // Language ID: en_US
static const DEFINE_USB_STRING(manufacturer_str,
        USB_STRING("B", "e", "R", "T", "O", "S"));
static const DEFINE_USB_STRING(product_str,
        USB_STRING("U", "S", "B", "-", "s", "e", "r", "i", "a", "l"));
static const DEFINE_USB_STRING(serial_str,
        USB_STRING("0", "0", "1"));

static const UsbStringDesc *usb_serial_strings[] =
{
    (const UsbStringDesc *)&language_str,
    (const UsbStringDesc *)&manufacturer_str,
    (const UsbStringDesc *)&product_str,
    (const UsbStringDesc *)&serial_str,
    NULL,
};

/* Global usb-serial descriptor that identifies the usb-serial device */
static UsbDevice usb_serial = {
    .device = &usb_serial_device_descriptor,
    .config = usb_serial_config,
    .strings = usb_serial_strings,
};

/* Low-level usb-serial device initialization */
static int usb_serial_hw_init(void)
{
#if CONFIG_KERN
    MOD_CHECK(proc);
#endif
    if (usb_deviceRegister(&usb_serial) < 0)
        return -1;
    LOG_INFO("usb-serial: registered new USB interface driver\n");
    return 0;
}

static size_t usb_serial_write(struct KFile *fd,
            const void *buf, size_t size)
{
    DB(USBSerial *fds = USB_SERIAL_CAST(fd));

    /* Silent compiler warnings if _DEBUG is not enabled */
    (void)fd;
    ASSERT(fds->is_open);
    return usb_endpointWrite(usb_serial_ep_in_descriptor.bEndpointAddress,
                buf, size);
}

static size_t usb_serial_read(struct KFile *fd, void *buf, size_t size)
{
    DB(USBSerial *fds = USB_SERIAL_CAST(fd));

    /* Silent compiler warnings if _DEBUG is not enabled */
    (void)fd;
    ASSERT(fds->is_open);
    return usb_endpointRead(usb_serial_ep_out_descriptor.bEndpointAddress,
                buf, size);
}

static int usb_serial_error(struct KFile *fd)
{
    USBSerial *fds = USB_SERIAL_CAST(fd);
    return fds->status;
}

static void usb_serial_clearerr(struct KFile *fd)
{
    USBSerial *fds = USB_SERIAL_CAST(fd);
    fds->status = 0;
}

static int usb_serial_close(struct KFile *fd)
{
    DB(USBSerial *fds = USB_SERIAL_CAST(fd));

    /* Silent compiler warnings if _DEBUG is not enabled */
    (void)fd;
    ASSERT(fds->is_open);
    DB(fds->is_open = false);
    return 0;
}

static int usb_serial_open(struct USBSerial *fds, int unit)
{
    unit = unit;
    ASSERT(!fds->is_open);
    /* TODO: only a single usb-serial unit is supported for now */
    ASSERT(unit == 0);

    /* Initialize usb-serial driver */
    if (usb_serial_hw_init() < 0)
        return -1;
    /* Clear error flags */
    fds->status = 0;
    DB(fds->is_open = true);

    return 0;
}

static struct KFile *usb_serial_reopen(struct KFile *fd)
{
    USBSerial *fds = USB_SERIAL_CAST(fd);

    usb_serial_close(fd);
    usb_serial_open(fds, fds->unit);
    return 0;
}

int usbser_init(struct USBSerial *fds, int unit)
{
    memset(fds, 0, sizeof(*fds));

    DB(fds->fd._type = KFT_USB_SERIAL);
    fds->fd.reopen = usb_serial_reopen;
    fds->fd.close = usb_serial_close;
    fds->fd.read = usb_serial_read;
    fds->fd.write = usb_serial_write;
    /* TODO: properly implement error handling. */
    fds->fd.error = usb_serial_error;
    fds->fd.clearerr = usb_serial_clearerr;

    return usb_serial_open(fds, unit);
}