On Thursday, November 23, 2017 3:46:55 PM CET Vincent Palatin wrote: > Add the hardware driver to acquire both USB Control Channels > using the Chromium "Twinkie" USB Power Delivery Analyzer dongle. > > Signed-off-by: Vincent Palatin <vpala...@chromium.org>
Some comments inline ...
Kind regards,
Stefan
> ---
> Makefile.am | 6 +
> configure.ac | 1 +
> contrib/60-libsigrok.rules | 3 +
> src/hardware/chromium-twinkie/api.c | 524
> +++++++++++++++++++++++++++++++ src/hardware/chromium-twinkie/protocol.c |
> 248 +++++++++++++++
> src/hardware/chromium-twinkie/protocol.h | 59 ++++
> 6 files changed, 841 insertions(+)
> create mode 100644 src/hardware/chromium-twinkie/api.c
> create mode 100644 src/hardware/chromium-twinkie/protocol.c
> create mode 100644 src/hardware/chromium-twinkie/protocol.h
>
> diff --git a/Makefile.am b/Makefile.am
> index 830d8cf9..dad304b6 100644
> --- a/Makefile.am
> +++ b/Makefile.am
> @@ -258,6 +258,12 @@ src_libdrivers_la_SOURCES += \
> src/hardware/center-3xx/protocol.c \
> src/hardware/center-3xx/api.c
> endif
> +if HW_CHROMIUM_TWINKIE
> +src_libdrivers_la_SOURCES += \
> + src/hardware/chromium-twinkie/protocol.h \
> + src/hardware/chromium-twinkie/protocol.c \
> + src/hardware/chromium-twinkie/api.c
> +endif
> if HW_CHRONOVU_LA
> src_libdrivers_la_SOURCES += \
> src/hardware/chronovu-la/protocol.h \
> diff --git a/configure.ac b/configure.ac
> index 56c097fa..16ebc0cc 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -229,6 +229,7 @@ SR_DRIVER([Brymen BM86x], [brymen-bm86x], [libusb])
> SR_DRIVER([Brymen DMM], [brymen-dmm], [libserialport])
> SR_DRIVER([CEM DT-885x], [cem-dt-885x], [libserialport])
> SR_DRIVER([Center 3xx], [center-3xx], [libserialport])
> +SR_DRIVER([Chromium Twinkie], [chromium-twinkie], [libusb])
> SR_DRIVER([ChronoVu LA], [chronovu-la], [libusb libftdi])
> SR_DRIVER([Colead SLM], [colead-slm], [libserialport])
> SR_DRIVER([Conrad DIGI 35 CPU], [conrad-digi-35-cpu], [libserialport])
> diff --git a/contrib/60-libsigrok.rules b/contrib/60-libsigrok.rules
> index 498f40cd..38dfabc8 100644
> --- a/contrib/60-libsigrok.rules
> +++ b/contrib/60-libsigrok.rules
> @@ -50,6 +50,9 @@ ATTRS{idVendor}=="0820", ATTRS{idProduct}=="0001",
> ENV{ID_SIGROK}="1" # CEM DT-8852
> ATTRS{idVendor}=="10c4", ATTRS{idProduct}=="ea60", ENV{ID_SIGROK}="1"
>
> +# Chromium Twinkie USB PD analyzer dongle
> +ATTRS{idVendor}=="18d1", ATTRS{idProduct}=="500a", ENV{ID_SIGROK}="1"
> +
> # ChronoVu LA8 (new VID/PID)
> # ChronoVu LA16 (new VID/PID)
> ATTRS{idVendor}=="0403", ATTRS{idProduct}=="8867", ENV{ID_SIGROK}="1"
> diff --git a/src/hardware/chromium-twinkie/api.c
> b/src/hardware/chromium-twinkie/api.c new file mode 100644
> index 00000000..15f4cf9f
> --- /dev/null
> +++ b/src/hardware/chromium-twinkie/api.c
> @@ -0,0 +1,524 @@
> +/*
> + * This file is part of the libsigrok project.
> + *
> + * Copyright 2017 Google, Inc
> + *
> + * 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 2 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 <libusb.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <math.h>
> +#include <libsigrok/libsigrok.h>
> +#include "libsigrok-internal.h"
> +#include "protocol.h"
> +
> +#define TWINKIE_VID 0x18d1
> +#define TWINKIE_PID 0x500a
> +
> +#define USB_INTERFACE 1
> +#define USB_CONFIGURATION 1
> +
> +#define MAX_RENUM_DELAY_MS 3000
> +#define NUM_SIMUL_TRANSFERS 32
> +
> +#define SAMPLE_RATE SR_KHZ(2400)
> +
> +static const int32_t hwopts[] = {
> + SR_CONF_CONN,
> +};
> +
> +static const int32_t hwcaps[] = {
> + SR_CONF_LOGIC_ANALYZER,
> + SR_CONF_CONTINUOUS,
> + SR_CONF_CONN | SR_CONF_GET,
> + SR_CONF_SAMPLERATE | SR_CONF_GET,
> + SR_CONF_LIMIT_SAMPLES | SR_CONF_SET,
> +};
> +
> +static const struct chan {
> + char *name;
> + int type;
> +} chan_defs[] = {
> + {"CC1", SR_CHANNEL_LOGIC},
> + {"CC2", SR_CHANNEL_LOGIC},
> +
> + {NULL, 0}
> +};
> +
> +static GSList *scan(struct sr_dev_driver *di, GSList *options)
> +{
> + struct drv_context *drvc;
> + struct dev_context *devc;
> + struct sr_dev_inst *sdi;
> + struct sr_usb_dev_inst *usb;
> + struct sr_channel *ch;
> + struct sr_config *src;
> + GSList *l, *devices, *conn_devices;
> + struct libusb_device_descriptor des;
> + libusb_device **devlist;
> + int ret, i, j;
> + const char *conn;
> + char connection_id[64];
> +
> + drvc = di->context;
> +
> + conn = NULL;
> + for (l = options; l; l = l->next) {
> + src = l->data;
> + switch (src->key) {
> + case SR_CONF_CONN:
> + conn = g_variant_get_string(src->data, NULL);
> + break;
> + }
> + }
> + if (conn)
> + conn_devices = sr_usb_find(drvc->sr_ctx->libusb_ctx, conn);
> + else
> + conn_devices = NULL;
> +
> + /* Find all Twinkie devices */
> + devices = NULL;
> + libusb_get_device_list(drvc->sr_ctx->libusb_ctx, &devlist);
> + for (i = 0; devlist[i]; i++) {
> + if (conn) {
> + usb = NULL;
> + for (l = conn_devices; l; l = l->next) {
> + usb = l->data;
> + if (usb->bus ==
> libusb_get_bus_number(devlist[i])
> + && usb->address ==
> libusb_get_device_address(devlist[i]))
> + break;
> + }
> + if (!l)
> + /* This device matched none of the ones that
> + * matched the conn specification. */
> + continue;
> + }
> +
> + if ((ret = libusb_get_device_descriptor(devlist[i], &des)) !=
> 0) {
> + sr_warn("Failed to get device descriptor: %s.",
> + libusb_error_name(ret));
> + continue;
> + }
> +
> + if (des.idVendor != TWINKIE_VID || des.idProduct != TWINKIE_PID)
> + continue;
> +
> + usb_get_port_path(devlist[i], connection_id,
> sizeof(connection_id));
> +
> + sdi = g_malloc0(sizeof(struct sr_dev_inst));
> + sdi->status = SR_ST_INITIALIZING;
> + sdi->vendor = g_strdup("Chromium");
> + sdi->model = g_strdup("Twinkie");
> + sdi->driver = di;
> + sdi->connection_id = g_strdup(connection_id);
> +
> + for (j = 0; chan_defs[j].name; j++)
> + if (!(ch = sr_channel_new(sdi, j, chan_defs[j].type,
> + TRUE, chan_defs[j].name)))
> + return NULL;
> +
> + if (!(devc = g_try_malloc0(sizeof(struct dev_context))))
> + return NULL;
You leak sdi here.
> + sdi->priv = devc;
> + drvc->instances = g_slist_append(drvc->instances, sdi);
> + devices = g_slist_append(devices, sdi);
> +
> + sr_dbg("Found a Twinkie dongle.");
> + sdi->status = SR_ST_INACTIVE;
> + sdi->inst_type = SR_INST_USB;
> + sdi->conn = sr_usb_dev_inst_new(
> + libusb_get_bus_number(devlist[i]),
> + libusb_get_device_address(devlist[i]), NULL);
> + }
> + libusb_free_device_list(devlist, 1);
> + g_slist_free_full(conn_devices, (GDestroyNotify)sr_usb_dev_inst_free);
> +
> + return devices;
> +}
> +
> +static int twinkie_dev_open(struct sr_dev_inst *sdi)
> +{
> + struct sr_dev_driver *di;
> + libusb_device **devlist;
> + struct sr_usb_dev_inst *usb;
> + struct libusb_device_descriptor des;
> + struct drv_context *drvc;
> + int ret, i, device_count;
> + char connection_id[64];
> +
> + di = sdi->driver;
> + drvc = di->context;
> + usb = sdi->conn;
> +
> + if (sdi->status == SR_ST_ACTIVE)
> + /* Device is already in use. */
> + return SR_ERR;
> +
> + device_count = libusb_get_device_list(drvc->sr_ctx->libusb_ctx,
> &devlist);
> + if (device_count < 0) {
> + sr_err("Failed to get device list: %s.",
> + libusb_error_name(device_count));
> + return SR_ERR;
> + }
> +
> + for (i = 0; i < device_count; i++) {
> + if ((ret = libusb_get_device_descriptor(devlist[i], &des))) {
> + sr_err("Failed to get device descriptor: %s.",
> + libusb_error_name(ret));
> + continue;
> + }
> +
> + if (des.idVendor != TWINKIE_VID || des.idProduct != TWINKIE_PID)
> + continue;
> +
> + if ((sdi->status == SR_ST_INITIALIZING) ||
> + (sdi->status == SR_ST_INACTIVE)) {
> + /*
> + * Check device by its physical USB bus/port address.
> + */
> + usb_get_port_path(devlist[i], connection_id,
> sizeof(connection_id));
> + if (strcmp(sdi->connection_id, connection_id))
> + /* This is not the one. */
> + continue;
> + }
> +
> + if (!(ret = libusb_open(devlist[i], &usb->devhdl))) {
> + if (usb->address == 0xff)
> + /*
> + * First time we touch this device after FW
> + * upload, so we don't know the address yet.
> + */
> + usb->address =
> libusb_get_device_address(devlist[i]);
> + } else {
> + sr_err("Failed to open device: %s.",
> + libusb_error_name(ret));
> + break;
> + }
> +
> + ret = libusb_claim_interface(usb->devhdl, USB_INTERFACE);
> + if (ret == LIBUSB_ERROR_BUSY) {
> + sr_err("Unable to claim USB interface. Another "
> + "program or driver has already claimed it.");
> + break;
> + } else if (ret == LIBUSB_ERROR_NO_DEVICE) {
> + sr_err("Device has been disconnected.");
> + break;
> + } else if (ret != 0) {
> + sr_err("Unable to claim interface: %s.",
> + libusb_error_name(ret));
> + break;
> + }
> +
> + if ((ret = twinkie_init_device(sdi)) != SR_OK) {
> + sr_err("Failed to init device.");
> + break;
> + }
> +
> + sdi->status = SR_ST_ACTIVE;
> + sr_info("Opened device %d.%d, interface %d.",
> + usb->bus, usb->address, USB_INTERFACE);
> +
> + break;
> + }
> + libusb_free_device_list(devlist, 1);
> +
> + if (sdi->status != SR_ST_ACTIVE) {
> + if (usb->devhdl) {
> + libusb_release_interface(usb->devhdl, USB_INTERFACE);
> + libusb_close(usb->devhdl);
> + usb->devhdl = NULL;
> + }
> + return SR_ERR;
> + }
> +
> + return SR_OK;
> +}
> +
> +static int dev_open(struct sr_dev_inst *sdi)
> +{
> + int ret;
> +
> + ret = twinkie_dev_open(sdi);
> + if (ret != SR_OK) {
> + sr_err("Unable to open device.");
> + return SR_ERR;
> + }
> +
> + return SR_OK;
> +}
> +
> +static int dev_close(struct sr_dev_inst *sdi)
> +{
> + struct sr_usb_dev_inst *usb;
> +
> + usb = sdi->conn;
> + if (usb->devhdl == NULL)
> + return SR_ERR;
> +
> + sr_info("Closing device %d.%d interface %d.",
> + usb->bus, usb->address, USB_INTERFACE);
> + libusb_release_interface(usb->devhdl, USB_INTERFACE);
> + libusb_close(usb->devhdl);
> + usb->devhdl = NULL;
> + sdi->status = SR_ST_INACTIVE;
> +
> + return SR_OK;
> +}
> +
> +static int dev_clear(const struct sr_dev_driver *di)
> +{
> + return std_dev_clear(di);
> +}
> +
> +static int config_get(uint32_t key, GVariant **data,
> + const struct sr_dev_inst *sdi,
> + const struct sr_channel_group *cg)
> +{
> + struct sr_usb_dev_inst *usb;
> + char str[128];
> + int ret;
> +
> + (void)cg;
> +
> + ret = SR_OK;
> + switch (key) {
> + case SR_CONF_CONN:
> + if (!sdi || !sdi->conn)
> + return SR_ERR_ARG;
> + usb = sdi->conn;
> + if (usb->address == 255)
> + /* Device still needs to re-enumerate after firmware
> + * upload, so we don't know its (future) address. */
> + return SR_ERR;
> + snprintf(str, 128, "%d.%d", usb->bus, usb->address);
> + *data = g_variant_new_string(str);
> + break;
> + case SR_CONF_SAMPLERATE:
> + *data = g_variant_new_uint64(SAMPLE_RATE);
> + break;
> + default:
> + return SR_ERR_NA;
> + }
> +
> + return ret;
> +}
> +
> +static int config_set(uint32_t key, GVariant *data,
> + const struct sr_dev_inst *sdi,
> + const struct sr_channel_group *cg)
> +{
> + struct dev_context *devc;
> + int ret;
> +
> + (void)cg;
> +
> + if (sdi->status != SR_ST_ACTIVE)
> + return SR_ERR_DEV_CLOSED;
> +
> + devc = sdi->priv;
> +
> + ret = SR_OK;
> + switch (key) {
> + case SR_CONF_LIMIT_SAMPLES:
> + devc->limit_samples = g_variant_get_uint64(data);
> + break;
> + default:
> + ret = SR_ERR_NA;
> + }
> +
> + return ret;
> +}
> +
> +static int config_list(uint32_t key, GVariant **data,
> + const struct sr_dev_inst *sdi,
> + const struct sr_channel_group *cg)
> +{
> + int ret;
> +
> + (void)sdi;
> + (void)cg;
> +
> + ret = SR_OK;
> + switch (key) {
> + case SR_CONF_SCAN_OPTIONS:
> + *data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
> + hwopts, ARRAY_SIZE(hwopts), sizeof(int32_t));
> + break;
> + case SR_CONF_DEVICE_OPTIONS:
> + *data = g_variant_new_fixed_array(G_VARIANT_TYPE_INT32,
> + hwcaps, ARRAY_SIZE(hwcaps), sizeof(int32_t));
> + break;
> + default:
> + return SR_ERR_NA;
> + }
> +
> + return ret;
> +}
> +
> +static void abort_acquisition(struct dev_context *devc)
> +{
> + int i;
> +
> + devc->sent_samples = -1;
> +
> + for (i = devc->num_transfers - 1; i >= 0; i--) {
> + if (devc->transfers[i])
> + libusb_cancel_transfer(devc->transfers[i]);
> + }
> +}
> +
> +static int receive_data(int fd, int revents, void *cb_data)
> +{
> + struct timeval tv;
> + struct dev_context *devc;
> + struct drv_context *drvc;
> + const struct sr_dev_inst *sdi;
> + struct sr_dev_driver *di;
> +
> + (void)fd;
> + (void)revents;
> +
> + sdi = cb_data;
> + di = sdi->driver;
> + drvc = di->context;
> + devc = sdi->priv;
> +
> + tv.tv_sec = tv.tv_usec = 0;
> + libusb_handle_events_timeout(drvc->sr_ctx->libusb_ctx, &tv);
> +
> + if (devc->sent_samples == -2) {
> + abort_acquisition(devc);
> + }
> +
> + return TRUE;
> +}
> +
> +static int dev_acquisition_start(const struct sr_dev_inst *sdi)
> +{
> + struct sr_dev_driver *di = sdi->driver;
> + struct dev_context *devc;
> + struct drv_context *drvc;
> + struct sr_usb_dev_inst *usb;
> + struct libusb_transfer *transfer;
> + unsigned int i, timeout, num_transfers;
> + int ret;
> + unsigned char *buf;
> + size_t size, convsize;
> +
> + if (sdi->status != SR_ST_ACTIVE)
> + return SR_ERR_DEV_CLOSED;
> +
> + drvc = di->context;
> + devc = sdi->priv;
> + usb = sdi->conn;
> +
> + devc->sent_samples = 0;
> + /* reset per-CC context */
> + memset(devc->cc, 0, sizeof(devc->cc));
> +
> + timeout = 1000;
> + num_transfers = 10;
> + size = 10*1024;
> + convsize = size * 8 * 256 /* largest size : only rollbacks/no edges */;
> + devc->submitted_transfers = 0;
> +
> + devc->convbuffer_size = convsize;
> + if (!(devc->convbuffer = g_try_malloc(convsize))) {
Are you sure you need a 20 MByte conversion buffer?
> + sr_err("Conversion buffer malloc failed.");
> + return SR_ERR_MALLOC;
> + }
> + memset(devc->convbuffer, 0, devc->convbuffer_size);
> +
> + devc->transfers = g_try_malloc0(sizeof(*devc->transfers) *
> num_transfers);
> + if (!devc->transfers) {
> + sr_err("USB transfers malloc failed.");
> + g_free(devc->convbuffer);
> + return SR_ERR_MALLOC;
> + }
> +
> + devc->num_transfers = num_transfers;
> + for (i = 0; i < num_transfers; i++) {
> + if (!(buf = g_try_malloc(size))) {
> + sr_err("USB transfer buffer malloc failed.");
> + if (devc->submitted_transfers)
> + abort_acquisition(devc);
> + else {
> + g_free(devc->transfers);
> + g_free(devc->convbuffer);
> + }
> + return SR_ERR_MALLOC;
> + }
> + transfer = libusb_alloc_transfer(0);
> + libusb_fill_bulk_transfer(transfer, usb->devhdl,
> + 3 | LIBUSB_ENDPOINT_IN, buf, size,
> + twinkie_receive_transfer, (void *)sdi, timeout);
> + if ((ret = libusb_submit_transfer(transfer)) != 0) {
> + sr_err("Failed to submit transfer: %s.",
> + libusb_error_name(ret));
> + libusb_free_transfer(transfer);
> + g_free(buf);
> + abort_acquisition(devc);
> + return SR_ERR;
> + }
> + devc->transfers[i] = transfer;
> + devc->submitted_transfers++;
> + }
> +
> + devc->ctx = drvc->sr_ctx;
> +
> + usb_source_add(sdi->session, devc->ctx, timeout, receive_data,
> + (void *)sdi);
> +
> + /* Send header packet to the session bus. */
> + std_session_send_df_header(sdi);
> +
> + if ((ret = twinkie_start_acquisition(sdi)) != SR_OK) {
> + abort_acquisition(devc);
> + return ret;
> + }
> +
> + return SR_OK;
> +}
> +
> +static int dev_acquisition_stop(struct sr_dev_inst *sdi)
> +{
> + if (sdi->status != SR_ST_ACTIVE)
> + return SR_ERR_DEV_CLOSED;
> +
> + abort_acquisition(sdi->priv);
> +
> + return SR_OK;
> +}
> +
> +static struct sr_dev_driver chromium_twinkie_driver_info = {
> + .name = "chromium-twinkie",
> + .longname = "Chromium Twinkie",
> + .api_version = 1,
> + .init = std_init,
> + .cleanup = std_cleanup,
> + .scan = scan,
> + .dev_list = std_dev_list,
> + .dev_clear = dev_clear,
> + .config_get = config_get,
> + .config_set = config_set,
> + .config_list = config_list,
> + .dev_open = dev_open,
> + .dev_close = dev_close,
> + .dev_acquisition_start = dev_acquisition_start,
> + .dev_acquisition_stop = dev_acquisition_stop,
> +};
> +SR_REGISTER_DEV_DRIVER(chromium_twinkie_driver_info);
> diff --git a/src/hardware/chromium-twinkie/protocol.c
> b/src/hardware/chromium-twinkie/protocol.c new file mode 100644
> index 00000000..c7327bd5
> --- /dev/null
> +++ b/src/hardware/chromium-twinkie/protocol.c
> @@ -0,0 +1,248 @@
> +/*
> + * This file is part of the libsigrok project.
> + *
> + * Copyright 2017 Google, Inc
> + *
> + * 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 2 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 <stdint.h>
> +#include <string.h>
> +#include <libusb.h>
> +#include <stdio.h>
> +#include <errno.h>
> +#include <math.h>
> +#include <libsigrok/libsigrok.h>
> +#include "libsigrok-internal.h"
> +#include "protocol.h"
> +
> +SR_PRIV int twinkie_start_acquisition(const struct sr_dev_inst *sdi)
> +{
> + (void)sdi;
> +
> + return SR_OK;
> +}
> +
> +SR_PRIV int twinkie_init_device(const struct sr_dev_inst *sdi)
> +{
> + (void)sdi;
> +
> + return SR_OK;
> +}
> +
> +static void finish_acquisition(struct sr_dev_inst *sdi)
> +{
> + struct sr_datafeed_packet packet;
> + struct dev_context *devc = sdi->priv;
> +
> + /* Terminate session. */
> + packet.type = SR_DF_END;
> + sr_session_send(sdi, &packet);
> +
> + /* Remove fds from polling. */
> + usb_source_remove(sdi->session, devc->ctx);
> +
> + devc->num_transfers = 0;
> + g_free(devc->transfers);
> + g_free(devc->convbuffer);
> +}
> +
> +static void free_transfer(struct libusb_transfer *transfer)
> +{
> + struct sr_dev_inst *sdi;
> + struct dev_context *devc;
> + unsigned int i;
> +
> + sdi = transfer->user_data;
> + devc = sdi->priv;
> +
> + g_free(transfer->buffer);
> + transfer->buffer = NULL;
> + libusb_free_transfer(transfer);
> +
> + for (i = 0; i < devc->num_transfers; i++) {
> + if (devc->transfers[i] == transfer) {
> + devc->transfers[i] = NULL;
> + break;
> + }
> + }
> +
> + devc->submitted_transfers--;
> + if (devc->submitted_transfers == 0)
> + finish_acquisition(sdi);
> +}
> +
> +static void export_samples(const struct sr_dev_inst *sdi, size_t cnt)
> +{
> + struct sr_datafeed_packet packet;
> + struct sr_datafeed_logic logic;
> + struct dev_context *devc = sdi->priv;
> +
> + /* export the received data */
> + packet.type = SR_DF_LOGIC;
> + packet.payload = &logic;
> + if (devc->limit_samples &&
> + cnt > devc->limit_samples - devc->sent_samples)
> + cnt = devc->limit_samples - devc->sent_samples;
> + logic.length = cnt;
> + logic.unitsize = 1;
> + logic.data = devc->convbuffer;
> + sr_session_send(sdi, &packet);
> + devc->sent_samples += cnt;
> +}
> +
Can you add information about the frame format? Apparently there is a header,
and the data seems to be compressed?
> +static void expand_sample_data(const struct sr_dev_inst *sdi,
> + const uint8_t *src, size_t srccnt)
> +{
> + struct dev_context *devc = sdi->priv;
> + int i, f;
> + size_t b;
> + size_t rdy_samples, left_samples;
> + int frames = srccnt / 64;
> +
> + for (f = 0; f < frames; f++) {
> + int ch = (src[1] >> 4) & 3; /* samples channel number */
> + int bit = 1 << ch; /* channel bit mask */
> + struct cc_context *cc = devc->cc + ch;
> + uint8_t *dest = devc->convbuffer + cc->idx;
> +
> + if (ch >= 2) /* only acquires CCx channels */
> + continue;
> +
> + /* TODO: check timestamp, overflow, sequence number */
> +
I think the function becomes easier to read if you put the loop body (i.e. the
frame parsing) into a separate function an call that from the loop.
> + /* skip header, go to edges data */
> + src+=4;
> + for (i = 0; i < 60; i++,src++)
> + if (*src == cc->prev_src) {
> + cc->rollbacks++;
> + } else {
> + uint8_t diff = *src - cc->prev_src;
> + int fixup = cc->rollbacks && (((int)*src <
> (int)cc->prev_src) ||
(*src
> == 0xff)); + size_t total = (fixup ? cc->rollbacks -
> 1 : cc-
>rollbacks)
> * 256 + diff; +
> + if (total + cc->idx > devc->convbuffer_size) {
> + sr_warn("overflow %d+%zd/%zd\n",
> + cc->idx, total,
> + devc->convbuffer_size);
> + /* reset current decoding */
> + cc->rollbacks = 0;
> + break;
> + }
> +
> + /* insert bits in the buffer */
> + if (cc->level)
> + for (b = 0 ; b < total ; b++, dest++)
> + *dest |= bit;
> + else
> + dest += total;
> + cc->idx += total;
> +
> + /* flip level on the next edge */
> + cc->level = ~cc->level;
> +
> + cc->rollbacks = 0;
> + cc->prev_src = *src;
> + }
> + /* expand repeated rollbacks */
> + if (cc->rollbacks > 1) {
> + size_t total = 256 * (cc->rollbacks - 1);
> + if (total + cc->idx > devc->convbuffer_size) {
> + sr_warn("overflow %d+%zd/%zd\n",
> + cc->idx, total, devc->convbuffer_size);
> + /* reset current decoding */
> + total = 0;
> + }
> + /* insert bits in the buffer */
> + if (cc->level)
> + for (b = 0 ; b < total ; b++, dest++)
> + *dest |= bit ;
> + cc->idx += total;
> + cc->rollbacks = 1;
> + }
> + }
> +
> + /* samples ready to be pushed (with both channels) */
> + rdy_samples = MIN(devc->cc[0].idx, devc->cc[1].idx);
> + left_samples = MAX(devc->cc[0].idx, devc->cc[1].idx) - rdy_samples;
> + /* skip empty transfer */
> + if (rdy_samples == 0)
> + return;
> +
> + export_samples(sdi, rdy_samples);
> +
> + /* clean up what we have sent */
> + memmove(devc->convbuffer, devc->convbuffer + rdy_samples, left_samples);
> + memset(devc->convbuffer + left_samples, 0, rdy_samples);
> + devc->cc[0].idx -= rdy_samples;
> + devc->cc[1].idx -= rdy_samples;
> +}
> +
> +SR_PRIV void LIBUSB_CALL twinkie_receive_transfer(struct libusb_transfer
> *transfer) +{
> + gboolean packet_has_error = FALSE;
> + struct sr_dev_inst *sdi;
> + struct dev_context *devc;
> +
> + sdi = transfer->user_data;
> + devc = sdi->priv;
> +
> + /*
> + * If acquisition has already ended, just free any queued up
> + * transfer that come in.
> + */
> + if (devc->sent_samples < 0) {
> + free_transfer(transfer);
> + return;
> + }
> +
> + if (transfer->status || transfer->actual_length)
> + sr_info("receive_transfer(): status %d received %d bytes.",
> + transfer->status, transfer->actual_length);
> +
> + switch (transfer->status) {
> + case LIBUSB_TRANSFER_NO_DEVICE:
> + devc->sent_samples = -2;
> + free_transfer(transfer);
> + return;
> + case LIBUSB_TRANSFER_COMPLETED:
> + case LIBUSB_TRANSFER_TIMED_OUT: /* We may have received some data
> though.
> */ + break;
> + default:
> + packet_has_error = TRUE;
> + break;
> + }
> +
> + if (transfer->actual_length % 64) {
> + sr_err("Bad USB packet size.");
> + packet_has_error = TRUE;
> + }
> +
> + if (transfer->actual_length == 0 || packet_has_error)
> + goto resubmit;
> +
> + /* decode received edges */
> + expand_sample_data(sdi, transfer->buffer, transfer->actual_length);
> +
> + if (devc->limit_samples &&
> + (uint64_t)devc->sent_samples >= devc->limit_samples) {
> + devc->sent_samples = -2;
> + free_transfer(transfer);
> + return;
> + }
> +resubmit:
> + if (libusb_submit_transfer(transfer) != LIBUSB_SUCCESS)
> + free_transfer(transfer);
> +}
> diff --git a/src/hardware/chromium-twinkie/protocol.h
> b/src/hardware/chromium-twinkie/protocol.h new file mode 100644
> index 00000000..3a282cc1
> --- /dev/null
> +++ b/src/hardware/chromium-twinkie/protocol.h
> @@ -0,0 +1,59 @@
> +/*
> + * This file is part of the libsigrok project.
> + *
> + * Copyright 2017 Google, Inc
> + *
> + * 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 2 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/>.
> + */
> +
> +#ifndef LIBSIGROK_HARDWARE_CHROMIUM_TWINKIE_PROTOCOL_H
> +#define LIBSIGROK_HARDWARE_CHROMIUM_TWINKIE_PROTOCOL_H
> +
> +#include <stdint.h>
> +#include <glib.h>
> +#include <libsigrok/libsigrok.h>
> +#include "libsigrok-internal.h"
> +
> +#define LOG_PREFIX "twinkie"
> +
> +/** Private, per-CC logical channel context. */
> +struct cc_context {
> + int idx;
> + int rollbacks;
> + uint8_t prev_src;
> + uint8_t level;
> +};
> +
> +/** Private, per-device-instance driver context. */
> +struct dev_context {
> + /** Maximum number of samples to capture, if nonzero. */
> + uint64_t limit_samples;
> +
> + int64_t sent_samples;
> + int submitted_transfers;
> + uint8_t *convbuffer;
> + size_t convbuffer_size;
> +
> + unsigned int num_transfers;
> + struct libusb_transfer **transfers;
> + struct sr_context *ctx;
> +
> + struct cc_context cc[2];
> +};
> +
> +SR_PRIV int twinkie_start_acquisition(const struct sr_dev_inst *sdi);
> +SR_PRIV int twinkie_init_device(const struct sr_dev_inst *sdi);
> +SR_PRIV void LIBUSB_CALL twinkie_receive_transfer(struct libusb_transfer
> *transfer); +
> +#endif
--
Stefan Brüns / Bergstraße 21 / 52062 Aachen
home: +49 241 53809034 mobile: +49 151 50412019
signature.asc
Description: This is a digitally signed message part.
------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________ sigrok-devel mailing list sigrok-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sigrok-devel
