+/*
+ * This file is part of the libsigrok project.
+ *
+ * Copyright (C) 2017 Carl-Fredrik Sundström <audio.cf@gmail.com>
+ * Copyright (C) 2017-2019 Gerhard Sittig <gerhard.sittig@gmx.net>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <config.h>
+#include <glib.h>
+#include <libsigrok/libsigrok.h>
+#include "libsigrok-internal.h"
+#include "serial_hid.h"
+#include <string.h>
+
+/** @cond PRIVATE */
+#define LOG_PREFIX "serial-cp2110"
+/** @endcond */
+
+#ifdef HAVE_SERIAL_COMM
+#ifdef HAVE_LIBHIDAPI
+
+/**
+ * @file
+ *
+ * Support serial-over-HID, specifically the SiLabs CP2110 chip.
+ */
+
+#define CP2110_MAX_BYTES_PER_REQUEST 63
+
+static const struct vid_pid_item vid_pid_items_cp2110[] = {
+ { 0x10c4, 0xea80, },
+ VID_PID_TERM,
+};
+
+enum cp2110_report_id {
+ CP2110_UART_ENDIS = 0x41,
+ CP2110_UART_STATUS = 0x42,
+ CP2110_FIFO_PURGE = 0x43,
+ CP2110_UART_CONFIG = 0x50,
+};
+
+enum cp2110_uart_enable_param {
+ CP2110_UART_DISABLE = 0,
+ CP2110_UART_ENABLE = 1,
+};
+
+enum cp2110_fifo_purge_flag {
+ CP2110_FIFO_PURGE_TX = (1 << 0),
+ CP2110_FIFO_PURGE_RX = (1 << 1),
+};
+
+enum cp2110_uart_config_bitrate {
+ CP2110_BAUDRATE_MIN = 300,
+ CP2110_BAUDRATE_MAX = 1000000,
+};
+
+enum cp2110_uart_config_databits {
+ CP2110_DATABITS_MIN = 5,
+ CP2110_DATABITS_MAX = 8,
+};
+
+enum cp2110_uart_config_parity {
+ CP2110_PARITY_NONE = 0,
+ CP2110_PARITY_EVEN = 1,
+ CP2110_PARITY_ODD = 2,
+ CP2110_PARITY_MARK = 3,
+ CP2110_PARITY_SPACE = 4,
+};
+
+enum cp2110_uart_config_stopbits {
+ CP2110_STOPBITS_SHORT = 0,
+ CP2110_STOPBITS_LONG = 1,
+};
+
+/* Hardware flow control on CP2110 is RTS/CTS only. */
+enum cp2110_uart_config_flowctrl {
+ CP2110_FLOWCTRL_NONE = 0,
+ CP2110_FLOWCTRL_HARD = 1,
+};
+
+static int cp2110_set_params(struct sr_serial_dev_inst *serial,
+ int baudrate, int bits, int parity, int stopbits,
+ int flowcontrol, int rts, int dtr)
+{
+ uint8_t report[9];
+ int replen;
+ int rc;
+
+ /* Map serial API specs to CP2110 register values. Check ranges. */
+ if (baudrate < CP2110_BAUDRATE_MIN || baudrate > CP2110_BAUDRATE_MAX) {
+ sr_err("CP2110: baudrate %d out of range", baudrate);
+ return SR_ERR_ARG;
+ }
+ if (bits < CP2110_DATABITS_MIN || bits > CP2110_DATABITS_MAX) {
+ sr_err("CP2110: %d databits out of range", bits);
+ return SR_ERR_ARG;
+ }
+ bits -= CP2110_DATABITS_MIN;
+ switch (parity) {
+ case SP_PARITY_NONE:
+ parity = CP2110_PARITY_NONE;
+ break;
+ case SP_PARITY_ODD:
+ parity = CP2110_PARITY_ODD;
+ break;
+ case SP_PARITY_EVEN:
+ parity = CP2110_PARITY_EVEN;
+ break;
+ case SP_PARITY_MARK:
+ parity = CP2110_PARITY_MARK;
+ break;
+ case SP_PARITY_SPACE:
+ parity = CP2110_PARITY_SPACE;
+ break;
+ default:
+ sr_err("CP2110: unknown parity spec %d", parity);
+ return SR_ERR_ARG;
+ }
+ switch (stopbits) {
+ case 1:
+ stopbits = CP2110_STOPBITS_SHORT;
+ break;
+ case 2:
+ stopbits = CP2110_STOPBITS_LONG;
+ break;
+ default:
+ sr_err("CP2110: unknown stop bits spec %d", stopbits);
+ return SR_ERR_ARG;
+ }
+ switch (flowcontrol) {
+ case SP_FLOWCONTROL_NONE:
+ flowcontrol = CP2110_FLOWCTRL_NONE;
+ break;
+ case SP_FLOWCONTROL_XONXOFF:
+ sr_err("CP2110: unsupported XON/XOFF flow control spec");
+ return SR_ERR_ARG;
+ case SP_FLOWCONTROL_RTSCTS:
+ flowcontrol = CP2110_FLOWCTRL_HARD;
+ break;
+ default:
+ sr_err("CP2110: unknown flow control spec %d", flowcontrol);
+ return SR_ERR_ARG;
+ }
+
+ /*
+ * Enable the UART. Report layout:
+ * @0, length 1, enabled state (0: disable, 1: enable)
+ */
+ replen = 0;
+ report[replen++] = CP2110_UART_ENDIS;
+ report[replen++] = CP2110_UART_ENABLE;
+ rc = ser_hid_hidapi_set_report(serial, report, replen);
+ if (rc < 0)
+ return SR_ERR;
+ if (rc != replen)
+ return SR_ERR;
+
+ /*
+ * Setup bitrate and frame format. Report layout:
+ * (@-1, length 1, report number)
+ * @0, length 4, bitrate (big endian format)
+ * @4, length 1, parity
+ * @5, length 1, flow control
+ * @6, length 1, data bits (0: 5, 1: 6, 2: 7, 3: 8)
+ * @7, length 1, stop bits
+ */
+ replen = 0;
+ report[replen++] = CP2110_UART_CONFIG;
+ WB32(&report[replen], baudrate);
+ replen += sizeof(uint32_t);
+ report[replen++] = parity;
+ report[replen++] = flowcontrol;
+ report[replen++] = bits;
+ report[replen++] = stopbits;
+ rc = ser_hid_hidapi_set_report(serial, report, replen);
+ if (rc < 0)
+ return SR_ERR;
+ if (rc != replen)
+ return SR_ERR;
+
+ /*
+ * Currently not implemented: Control RTS and DTR state.
+ * TODO are these controlled via GPIO requests?
+ * GPIO.1 == RTS, can't find DTR in AN433 table 4.3
+ */
+ (void)rts;
+ (void)dtr;
+
+ return SR_OK;
+}
+
+static int cp2110_read_bytes(struct sr_serial_dev_inst *serial,
+ uint8_t *data, int space, unsigned int timeout)
+{
+ uint8_t buffer[1 + CP2110_MAX_BYTES_PER_REQUEST];
+ int rc;
+ int count;
+
+ (void)timeout;
+
+ /*
+ * Check for available input data from the serial port.
+ * Packet layout:
+ * @0, length 1, number of bytes, range 0-63
+ * @1, length N, data bytes
+ */
+ memset(buffer, 0, sizeof(buffer));
+ rc = ser_hid_hidapi_get_data(serial, 0, buffer, sizeof(buffer), timeout);
+ if (rc == SR_ERR_TIMEOUT)
+ return 0;
+ if (rc < 0)
+ return SR_ERR;
+ if (rc == 0)
+ return 0;
+ sr_dbg("DBG: %s() got report len %d, 0x%02x.", __func__, rc, buffer[0]);
+
+ /* Check the length spec, get the byte count. */
+ count = buffer[0];
+ if (!count)
+ return 0;
+ if (count > CP2110_MAX_BYTES_PER_REQUEST)
+ return SR_ERR;
+ sr_dbg("DBG: %s(), got %d UART RX bytes.", __func__, count);
+ if (count > space)
+ return SR_ERR;
+
+ /* Pass received data bytes and their count to the caller. */
+ memcpy(data, &buffer[1], count);
+ return count;
+}
+
+static int cp2110_write_bytes(struct sr_serial_dev_inst *serial,
+ const uint8_t *data, int size)
+{
+ uint8_t buffer[1 + CP2110_MAX_BYTES_PER_REQUEST];
+ int rc;
+
+ sr_dbg("DBG: %s() shall send UART TX data, len %d.", __func__, size);
+
+ if (size < 1)
+ return 0;
+ if (size > CP2110_MAX_BYTES_PER_REQUEST) {
+ size = CP2110_MAX_BYTES_PER_REQUEST;
+ sr_dbg("DBG: %s() capping size to %d.", __func__, size);
+ }
+
+ /*
+ * Packet layout to send serial data to the USB HID chip:
+ * @0, length 1, number of bytes, range 0-63
+ * @1, length N, data bytes
+ */
+ buffer[0] = size;
+ memcpy(&buffer[1], data, size);
+ rc = ser_hid_hidapi_set_data(serial, 0, buffer, sizeof(buffer), 0);
+ if (rc < 0)
+ return rc;
+ if (rc == 0)
+ return 0;
+ return size;
+}
+
+static int cp2110_flush(struct sr_serial_dev_inst *serial)
+{
+ uint8_t buffer[2];
+ int rc;
+
+ sr_dbg("DBG: %s() discarding RX and TX FIFO data.", __func__);
+
+ buffer[0] = CP2110_FIFO_PURGE;
+ buffer[1] = CP2110_FIFO_PURGE_TX | CP2110_FIFO_PURGE_RX;
+ rc = ser_hid_hidapi_set_data(serial, 0, buffer, sizeof(buffer), 0);
+ if (rc != 0)
+ return SR_ERR;
+ return SR_OK;
+}
+
+static int cp2110_drain(struct sr_serial_dev_inst *serial)
+{
+ uint8_t buffer[7];
+ int rc;
+ uint16_t tx_fill, rx_fill;
+
+ sr_dbg("DBG: %s() waiting for TX data to drain.", __func__);
+
+ /*
+ * Keep retrieving the UART status until the FIFO is found empty,
+ * or an error occured.
+ * Packet layout:
+ * @0, length 1, report ID
+ * @1, length 2, number of bytes in the TX FIFO (up to 480)
+ * @3, length 2, number of bytes in the RX FIFO (up to 480)
+ * @5, length 1, error status (parity and overrun error flags)
+ * @6, length 1, line break status
+ */
+ rx_fill = ~0;
+ do {
+ memset(buffer, 0, sizeof(buffer));
+ buffer[0] = CP2110_UART_STATUS;
+ rc = ser_hid_hidapi_get_data(serial, 0, buffer, sizeof(buffer), 0);
+ if (rc != sizeof(buffer)) {
+ rc = SR_ERR_DATA;
+ break;
+ }
+ if (buffer[0] != CP2110_UART_STATUS) {
+ rc = SR_ERR_DATA;
+ break;
+ }
+ rx_fill = RB16(&buffer[1]);
+ tx_fill = RB16(&buffer[3]);
+ if (!tx_fill) {
+ rc = SR_OK;
+ break;
+ }
+ g_usleep(2000);
+ } while (1);
+
+ sr_dbg("DBG: %s() TX drained, rc %d, RX fill %u, returning.",
+ __func__, rc, (unsigned int)rx_fill);
+ return rc;
+}
+
+static struct ser_hid_chip_functions chip_cp2110 = {
+ .chipname = "cp2110",
+ .chipdesc = "SiLabs CP2110",
+ .vid_pid_items = vid_pid_items_cp2110,
+ .max_bytes_per_request = CP2110_MAX_BYTES_PER_REQUEST,
+ .set_params = cp2110_set_params,
+ .read_bytes = cp2110_read_bytes,
+ .write_bytes = cp2110_write_bytes,
+ .flush = cp2110_flush,
+ .drain = cp2110_drain,
+};
+SR_PRIV struct ser_hid_chip_functions *ser_hid_chip_funcs_cp2110 = &chip_cp2110;
+
+#else
+
+SR_PRIV struct ser_hid_chip_functions *ser_hid_chip_funcs_cp2110 = NULL;
+
+#endif
+#endif
projects / libsigrok.git / commitdiff