| /* |
| * usb_gps.c |
| * |
| * Copyright (C) 2019-2022 Sylvain Munaut <tnt@246tNt.com> |
| * SPDX-License-Identifier: GPL-3.0-or-later |
| */ |
| |
| #include <stdint.h> |
| #include <stdbool.h> |
| #include <string.h> |
| |
| #include <no2usb/usb.h> |
| #include <no2usb/usb_hw.h> |
| #include <no2usb/usb_priv.h> |
| |
| #include <no2usb/usb_proto.h> |
| #include <no2usb/usb_cdc_proto.h> |
| |
| #include "console.h" |
| #include "misc.h" |
| #include "usb_desc_ids.h" |
| |
| |
| #define BUF_SIZE_LOG 9 |
| #define BUF_SIZE (1 << BUF_SIZE_LOG) |
| #define BUF_MASK (BUF_SIZE - 1) |
| |
| static struct { |
| /* State */ |
| bool active; |
| |
| /* Buffer */ |
| struct { |
| unsigned int wr; |
| unsigned int rd; |
| char data[BUF_SIZE] __attribute__((aligned(4))); |
| } buf; |
| |
| #ifdef GPS_PPS_ON_CD |
| /* PPS tracking */ |
| struct { |
| uint32_t last; |
| bool set; |
| } pps; |
| #endif |
| } g_usb_gps; |
| |
| |
| struct usb_cdc_notif_serial_state { |
| struct usb_ctrl_req hdr; |
| uint16_t bits; |
| }; |
| |
| |
| static void |
| _usb_gps_set_active(bool active) |
| { |
| /* Save new state */ |
| g_usb_gps.active = active; |
| |
| /* Reset FIFO if disabled */ |
| if (!active) |
| g_usb_gps.buf.wr = g_usb_gps.buf.rd = 0; |
| } |
| |
| static int |
| _usb_gps_fill_packet(unsigned int dst_ofs) |
| { |
| unsigned int len; |
| |
| /* Len available, limited to 64 */ |
| len = (g_usb_gps.buf.wr - g_usb_gps.buf.rd) & BUF_MASK; |
| |
| if (len > 64) |
| len = 64; |
| |
| /* Copy block */ |
| usb_data_write(dst_ofs, &g_usb_gps.buf.data[g_usb_gps.buf.rd], (len + 3) & ~3); |
| |
| /* Increment read pointer */ |
| g_usb_gps.buf.rd = (g_usb_gps.buf.rd + len) & BUF_MASK; |
| |
| /* If length was not multiple of 4, we emptied the FIFO, |
| * so we reset it to 0 so we're aligned again */ |
| if (len & 3) |
| g_usb_gps.buf.wr = g_usb_gps.buf.rd = 0; |
| |
| return len; |
| } |
| |
| |
| void |
| usb_gps_puts(const char *str) |
| { |
| unsigned int nxt; |
| char c; |
| |
| if (!g_usb_gps.active) |
| return; |
| |
| while ((c = *str++) != '\0') |
| { |
| /* Next write pointer pos and full check */ |
| nxt = (g_usb_gps.buf.wr + 1) & BUF_MASK; |
| if (nxt == g_usb_gps.buf.rd) |
| /* If overflow, we keep the latest content ... */ |
| g_usb_gps.buf.rd = (g_usb_gps.buf.rd + 1) & BUF_MASK; |
| |
| /* Write data */ |
| g_usb_gps.buf.data[g_usb_gps.buf.wr] = c; |
| |
| /* Update write pointer */ |
| g_usb_gps.buf.wr = nxt; |
| } |
| } |
| |
| void |
| usb_gps_poll(void) |
| { |
| volatile struct usb_ep *ep_regs; |
| |
| /* OUT EP: We accept data and throw it away */ |
| ep_regs = &usb_ep_regs[USB_EP_GPS_CDC_OUT & 0x1f].out; |
| ep_regs->bd[0].csr = USB_BD_STATE_RDY_DATA | USB_BD_LEN(64); |
| |
| /* IN EP: Send whatever is queued */ |
| ep_regs = &usb_ep_regs[USB_EP_GPS_CDC_OUT & 0x1f].in; |
| |
| if ((ep_regs->bd[0].csr & USB_BD_STATE_MSK) != USB_BD_STATE_RDY_DATA) |
| { |
| int len = _usb_gps_fill_packet(ep_regs->bd[0].ptr); |
| |
| if (len) |
| ep_regs->bd[0].csr = USB_BD_STATE_RDY_DATA | USB_BD_LEN(len); |
| else |
| ep_regs->bd[0].csr = 0; |
| } |
| |
| #ifdef GPS_PPS_ON_CD |
| /* IN EP CTL: Send PPS pulse */ |
| ep_regs = &usb_ep_regs[USB_EP_GPS_CDC_CTL & 0x1f].in; |
| |
| if ((ep_regs->bd[0].csr & USB_BD_STATE_MSK) != USB_BD_STATE_RDY_DATA) |
| { |
| /* Default request */ |
| struct usb_cdc_notif_serial_state notif = { |
| .hdr = { |
| .bmRequestType = USB_REQ_READ | USB_REQ_TYPE_CLASS | USB_REQ_RCPT_INTF, |
| .bRequest = USB_NOTIF_CDC_SERIAL_STATE, |
| .wValue = 0, |
| .wIndex = USB_INTF_GPS_CDC_CTL, |
| .wLength = 2 |
| }, |
| .bits = 0x00 |
| }; |
| |
| /* Check if PPS occurred */ |
| uint32_t pps_now = time_pps_read(); |
| |
| if (pps_now != g_usb_gps.pps.last) |
| { |
| /* Update last */ |
| g_usb_gps.pps.last = pps_now; |
| |
| /* Queue CD Set */ |
| notif.bits = 1; |
| usb_data_write(ep_regs->bd[0].ptr, ¬if, 12); |
| ep_regs->bd[0].csr = USB_BD_STATE_RDY_DATA | USB_BD_LEN(10); |
| |
| /* Need to clear in the future */ |
| g_usb_gps.pps.set = true; |
| } |
| else if (g_usb_gps.pps.set) |
| { |
| /* Queue CD Clear */ |
| notif.bits = 0; |
| usb_data_write(ep_regs->bd[0].ptr, ¬if, 12); |
| ep_regs->bd[0].csr = USB_BD_STATE_RDY_DATA | USB_BD_LEN(10); |
| |
| /* Cleared */ |
| g_usb_gps.pps.set = false; |
| } |
| } |
| #endif |
| } |
| |
| |
| static enum usb_fnd_resp |
| _cdc_set_conf(const struct usb_conf_desc *conf) |
| { |
| const struct usb_intf_desc *intf; |
| |
| if (!conf) |
| return USB_FND_SUCCESS; |
| |
| /* Configure control interface */ |
| intf = usb_desc_find_intf(conf, USB_INTF_GPS_CDC_CTL, 0, NULL); |
| if (!intf) |
| return USB_FND_ERROR; |
| |
| usb_ep_boot(intf, USB_EP_GPS_CDC_CTL, false); |
| |
| /* Configure data interface */ |
| intf = usb_desc_find_intf(conf, USB_INTF_GPS_CDC_DATA, 0, NULL); |
| if (!intf) |
| return USB_FND_ERROR; |
| |
| usb_ep_boot(intf, USB_EP_GPS_CDC_OUT, false); |
| usb_ep_boot(intf, USB_EP_GPS_CDC_IN, false); |
| |
| return USB_FND_SUCCESS; |
| } |
| |
| static enum usb_fnd_resp |
| _cdc_ctrl_req(struct usb_ctrl_req *req, struct usb_xfer *xfer) |
| { |
| static const struct usb_cdc_line_coding linecoding = { |
| .dwDTERate = 115200, |
| .bCharFormat = 2, |
| .bParityType = 0, |
| .bDataBits = 8, |
| }; |
| |
| /* Check this is handled here */ |
| if (USB_REQ_TYPE_RCPT(req) != (USB_REQ_TYPE_CLASS | USB_REQ_RCPT_INTF)) |
| return USB_FND_CONTINUE; |
| |
| if (req->wIndex != USB_INTF_GPS_CDC_CTL) |
| return USB_FND_CONTINUE; |
| |
| /* Process request */ |
| switch (req->bRequest) { |
| case USB_REQ_CDC_SEND_ENCAPSULATED_COMMAND: |
| /* We don't support any, so just accept and don't care */ |
| return USB_FND_SUCCESS; |
| |
| case USB_REQ_CDC_GET_ENCAPSULATED_RESPONSE: |
| /* Never anything to return */ |
| xfer->len = 0; |
| return USB_FND_SUCCESS; |
| |
| case USB_REQ_CDC_SET_LINE_CODING: |
| /* We only support 1 config, doesn't matter what the hosts sends */ |
| return USB_FND_SUCCESS; |
| |
| case USB_REQ_CDC_GET_LINE_CODING: |
| /* We only support 1 config, send that back */ |
| xfer->data = (void*)&linecoding; |
| xfer->len = sizeof(linecoding); |
| return USB_FND_ERROR; |
| |
| case USB_REQ_CDC_SET_CONTROL_LINE_STATE: |
| /* Enable if DTR is set */ |
| _usb_gps_set_active((req->wValue & 1) != 0); |
| return USB_FND_SUCCESS; |
| } |
| |
| /* Anything else is not handled */ |
| return USB_FND_ERROR; |
| } |
| |
| |
| static struct usb_fn_drv _cdc_drv = { |
| .set_conf = _cdc_set_conf, |
| .ctrl_req = _cdc_ctrl_req, |
| }; |
| |
| void |
| usb_gps_init(void) |
| { |
| memset(&g_usb_gps, 0x00, sizeof(g_usb_gps)); |
| usb_register_function_driver(&_cdc_drv); |
| } |