chromium-twinkie: add analog VBUS channels

Retrieve VBUS voltage and current through packetized console commands if
this interface exists and analog channels are enabled.

Signed-off-by: Vincent Palatin <redacted>

diff --git a/src/hardware/chromium-twinkie/api.c b/src/hardware/chromium-twinkie/api.c
index 7e9f20a8815694a1015d7fc7ca979957f96b11e4..f0b29e27870360342d9b823dfffce0c37639e14e 100644 (file)
--- a/src/hardware/chromium-twinkie/api.c
+++ b/src/hardware/chromium-twinkie/api.c
@@ -1,7 +1,7 @@
 /*
  * This file is part of the libsigrok project.
  *
- * Copyright 2014 Google, Inc
+ * 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
@@ -31,14 +31,21 @@
 
 #define USB_INTERFACE          1
 #define USB_CONFIGURATION      1
+#define USB_COMMANDS_IFACE     2
 
 #define MAX_RENUM_DELAY_MS     3000
 #define NUM_SIMUL_TRANSFERS    32
 
 #define SAMPLE_RATE            SR_KHZ(2400)
 
+static const char vbus_cmd[] = "tw vbus";
+
+/* CC1 & CC2 are always present */
+#define LOGIC_CHANNELS_COUNT    2
+
 static const int32_t hwopts[] = {
        SR_CONF_CONN,
+       SR_CONF_NUM_ANALOG_CHANNELS,
 };
 
 static const int32_t hwcaps[] = {
@@ -55,6 +62,8 @@ static const struct chan {
 } chan_defs[] = {
        {"CC1", SR_CHANNEL_LOGIC},
        {"CC2", SR_CHANNEL_LOGIC},
+       {"VBUS_V", SR_CHANNEL_ANALOG},
+       {"VBUS_A", SR_CHANNEL_ANALOG},
 
        {NULL, 0}
 };
@@ -66,13 +75,17 @@ static GSList *scan(struct sr_dev_driver *di, GSList *options)
        struct sr_dev_inst *sdi;
        struct sr_usb_dev_inst *usb;
        struct sr_channel *ch;
+       struct sr_channel_group *cc_grp, *vbus_grp[VBUS_GRP_COUNT];
        struct sr_config *src;
        GSList *l, *devices, *conn_devices;
        struct libusb_device_descriptor des;
+       struct libusb_config_descriptor *cfg;
        libusb_device **devlist;
        int ret, i, j;
        const char *conn;
        char connection_id[64];
+       /* By default, disable VBUS analog */
+       int vbus_channels = 0;
 
        drvc = di->context;
 
@@ -83,6 +96,9 @@ static GSList *scan(struct sr_dev_driver *di, GSList *options)
                case SR_CONF_CONN:
                        conn = g_variant_get_string(src->data, NULL);
                        break;
+               case SR_CONF_NUM_ANALOG_CHANNELS:
+                       vbus_channels = MIN(2, g_variant_get_int32(src->data));
+                       break;
                }
        }
        if (conn)
@@ -117,6 +133,12 @@ static GSList *scan(struct sr_dev_driver *di, GSList *options)
                if (des.idVendor != TWINKIE_VID || des.idProduct != TWINKIE_PID)
                        continue;
 
+               if ((ret = libusb_get_active_config_descriptor(devlist[i], &cfg)) != 0) {
+                       sr_warn("Failed to get device configuraton: %s.",
+                               libusb_error_name(ret));
+                       continue;
+               }
+
                usb_get_port_path(devlist[i], connection_id, sizeof(connection_id));
 
                sdi = g_malloc0(sizeof(struct sr_dev_inst));
@@ -126,14 +148,53 @@ static GSList *scan(struct sr_dev_driver *di, GSList *options)
                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 (vbus_channels && cfg->bNumInterfaces < 3) {
+                       sr_warn("VBUS channels not available in this firmware.");
+                       vbus_channels = 0;
+               }
 
                if (!(devc = g_try_malloc0(sizeof(struct dev_context))))
                        return NULL;
                sdi->priv = devc;
+
+               cc_grp = g_malloc0(sizeof(struct sr_channel_group));
+               cc_grp->name = g_strdup("CCx");
+               for (j = 0; j < vbus_channels; j++) {
+                       vbus_grp[j] = g_malloc0(sizeof(struct sr_channel_group));
+                       vbus_grp[j]->name = g_strdup(j == VBUS_V ? "VBUS_V"
+                                                                : "VBUS_A");
+               }
+
+               for (j = 0; chan_defs[j].name; j++) {
+                       struct sr_channel_group *grp = cc_grp;
+                       if (j >= LOGIC_CHANNELS_COUNT) { /* Analog channels */
+                               if (j - LOGIC_CHANNELS_COUNT >= vbus_channels)
+                                       break;
+                               grp = vbus_grp[j - LOGIC_CHANNELS_COUNT];
+                       }
+                       ch = sr_channel_new(sdi, j, chan_defs[j].type, TRUE,
+                                           chan_defs[j].name);
+                       grp->channels = g_slist_append(grp->channels, ch);
+               }
+               sdi->channel_groups = g_slist_append(NULL, cc_grp);
+               for (j = 0; j < vbus_channels; j++) {
+                       sdi->channel_groups = g_slist_append(sdi->channel_groups,
+                                                            vbus_grp[j]);
+                       sr_analog_init(&devc->vbus_packet[j],
+                                      &devc->vbus_encoding,
+                                      &devc->vbus_meaning[j],
+                                      &devc->vbus_spec, 3);
+                       devc->vbus_meaning[j].channels = vbus_grp[j]->channels;
+               }
+               /* other encoding default settings in sr_analog_init are OK (eg float) */
+               devc->vbus_encoding.is_signed = TRUE;
+               devc->vbus_meaning[VBUS_V].mq = SR_MQ_VOLTAGE;
+               devc->vbus_meaning[VBUS_V].mqflags = SR_MQFLAG_DC;
+               devc->vbus_meaning[VBUS_V].unit = SR_UNIT_VOLT;
+               devc->vbus_meaning[VBUS_A].mq = SR_MQ_CURRENT;
+               devc->vbus_meaning[VBUS_A].unit = SR_UNIT_AMPERE;
+
+               devc->vbus_channels = vbus_channels;
                drvc->instances = g_slist_append(drvc->instances, sdi);
                devices = g_slist_append(devices, sdi);
 
@@ -150,17 +211,19 @@ static GSList *scan(struct sr_dev_driver *di, GSList *options)
        return devices;
 }
 
-static int twinkie_dev_open(struct sr_dev_inst *sdi)
+static int 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;
+       struct dev_context *devc;
        int ret, i, device_count;
        char connection_id[64];
 
        di = sdi->driver;
+       devc = sdi->priv;
        drvc = di->context;
        usb = sdi->conn;
 
@@ -222,6 +285,13 @@ static int twinkie_dev_open(struct sr_dev_inst *sdi)
                               libusb_error_name(ret));
                        break;
                }
+               if (devc->vbus_channels &&
+                   (ret = libusb_claim_interface(usb->devhdl, USB_COMMANDS_IFACE))) {
+                       sr_err("Unable to claim commands interface %d/%s.", ret,
+                              libusb_error_name(ret));
+                       /* Cannot use the analog channels for VBUS. */
+                       devc->vbus_channels = 0;
+               }
 
                if ((ret = twinkie_init_device(sdi)) != SR_OK) {
                        sr_err("Failed to init device.");
@@ -248,29 +318,19 @@ static int twinkie_dev_open(struct sr_dev_inst *sdi)
        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;
+       struct dev_context *devc;
 
        usb = sdi->conn;
        if (usb->devhdl == NULL)
                return SR_ERR;
 
-       sr_info("Closing device %d.%d interface %d.",
-               usb->bus, usb->address, USB_INTERFACE);
+       sr_info("Closing device %d.%d.", usb->bus, usb->address);
+       devc = sdi->priv;
+       if (devc->vbus_channels)
+               libusb_release_interface(usb->devhdl, USB_COMMANDS_IFACE);
        libusb_release_interface(usb->devhdl, USB_INTERFACE);
        libusb_close(usb->devhdl);
        usb->devhdl = NULL;
@@ -279,11 +339,6 @@ static int dev_close(struct sr_dev_inst *sdi)
        return SR_OK;
 }
 
-static int dev_clear(const struct sr_dev_driver *di)
-{
-       return std_dev_clear(di, NULL);
-}
-
 static int config_get(uint32_t key, GVariant **data,
                const struct sr_dev_inst *sdi,
                const struct sr_channel_group *cg)
@@ -414,7 +469,7 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi)
        struct drv_context *drvc;
        struct sr_usb_dev_inst *usb;
        struct libusb_transfer *transfer;
-       unsigned int i, timeout, num_transfers;
+       unsigned int i, timeout, num_transfers, cc_transfers;
        int ret;
        unsigned char *buf;
        size_t size, convsize;
@@ -431,10 +486,12 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi)
        memset(devc->cc, 0, sizeof(devc->cc));
 
        timeout = 1000;
-       num_transfers = 10;
+       cc_transfers = num_transfers = 10;
        size = 10*1024;
        convsize = size * 8 * 256 /* largest size : only rollbacks/no edges */;
        devc->submitted_transfers = 0;
+       if (devc->vbus_channels)
+               num_transfers += 2;
 
        devc->convbuffer_size = convsize;
        if (!(devc->convbuffer = g_try_malloc(convsize))) {
@@ -451,7 +508,7 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi)
        }
 
        devc->num_transfers = num_transfers;
-       for (i = 0; i < num_transfers; i++) {
+       for (i = 0; i < cc_transfers; i++) {
                if (!(buf = g_try_malloc(size))) {
                        sr_err("USB transfer buffer malloc failed.");
                        if (devc->submitted_transfers)
@@ -477,6 +534,28 @@ static int dev_acquisition_start(const struct sr_dev_inst *sdi)
                devc->transfers[i] = transfer;
                devc->submitted_transfers++;
        }
+       if (devc->vbus_channels) {
+               struct libusb_transfer *out_xfer = libusb_alloc_transfer(0);
+               struct libusb_transfer *in_xfer = libusb_alloc_transfer(0);
+               libusb_fill_bulk_transfer(out_xfer, usb->devhdl,
+                                         2 | LIBUSB_ENDPOINT_OUT, (uint8_t *)vbus_cmd,
+                                         sizeof(vbus_cmd) - 1, twinkie_vbus_sent,
+                                         (void *)sdi, timeout);
+               libusb_fill_bulk_transfer(in_xfer, usb->devhdl,
+                                         2 | LIBUSB_ENDPOINT_IN, (uint8_t *)devc->vbus_data,
+                                         sizeof(devc->vbus_data),
+                                         twinkie_vbus_recv, (void *)sdi, timeout);
+               if ((ret = libusb_submit_transfer(out_xfer)) != 0) {
+                       sr_err("Failed to submit VBUS transfer: %s.",
+                              libusb_error_name(ret));
+                       libusb_free_transfer(out_xfer);
+                       abort_acquisition(devc);
+                       return SR_ERR;
+               }
+               devc->transfers[cc_transfers + 0] = out_xfer;
+               devc->transfers[cc_transfers + 1] = in_xfer;
+               devc->submitted_transfers++;
+       }
 
        devc->ctx = drvc->sr_ctx;
 
@@ -512,7 +591,7 @@ static struct sr_dev_driver chromium_twinkie_driver_info = {
        .cleanup = std_cleanup,
        .scan = scan,
        .dev_list = std_dev_list,
-       .dev_clear = dev_clear,
+       .dev_clear = NULL,
        .config_get = config_get,
        .config_set = config_set,
        .config_list = config_list,

diff --git a/src/hardware/chromium-twinkie/protocol.c b/src/hardware/chromium-twinkie/protocol.c
index 9640ba6fb0aba7cf867c234f6e5d2e1edca31f8e..562df3cf1d037222793dc754f13a736ff21f4219 100644 (file)
--- a/src/hardware/chromium-twinkie/protocol.c
+++ b/src/hardware/chromium-twinkie/protocol.c
@@ -1,7 +1,7 @@
 /*
  * This file is part of the libsigrok project.
  *
- * Copyright 2014 Google, Inc
+ * 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
@@ -28,9 +28,16 @@
 #include "libsigrok-internal.h"
 #include "protocol.h"
 
+/* 'twinkie vbus' command output format */
+#define VBUS_FORMAT "VBUS = %d mV ; %d mA"
+
 SR_PRIV int twinkie_start_acquisition(const struct sr_dev_inst *sdi)
 {
-       (void)sdi;
+       struct dev_context *devc = sdi->priv;
+       struct timespec tsample;
+
+       clock_gettime(CLOCK_REALTIME, &tsample);
+       devc->vbus_t0 = tsample.tv_nsec + (uint64_t)tsample.tv_sec *1000000000ULL;
 
        return SR_OK;
 }
@@ -246,3 +253,100 @@ resubmit:
        if (libusb_submit_transfer(transfer) != LIBUSB_SUCCESS)
                free_transfer(transfer);
 }
+
+static void export_vbus(const struct sr_dev_inst *sdi, int mv, int ma)
+{
+       static float tmp_data[VBUS_GRP_COUNT][32768];
+       struct dev_context *devc = sdi->priv;
+       struct sr_datafeed_packet packet[VBUS_GRP_COUNT];
+       uint64_t tlen = devc->vbus_delta * 24 / 10000;
+       uint64_t len = MIN(32768, tlen);
+       unsigned i, g;
+
+       for (g = 0; g < devc->vbus_channels; g++) {
+               float val = g == VBUS_V ? mv/1000.0 : ma/1000.0;
+               packet[g].type = SR_DF_ANALOG;
+               packet[g].payload = &devc->vbus_packet[g];
+               devc->vbus_packet[g].data = tmp_data[g];
+               for (i = 0; i < len; i++)
+                       tmp_data[g][i] = val;
+       }
+
+       do {
+               for (g = 0; g < devc->vbus_channels; g++) {
+                       devc->vbus_packet[g].num_samples = len;
+                       sr_session_send(sdi, &packet[g]);
+               }
+               tlen -= len;
+               len = MIN(32768, tlen);
+       } while (tlen);
+}
+
+SR_PRIV void twinkie_vbus_sent(struct libusb_transfer *transfer)
+{
+       struct sr_dev_inst *sdi = transfer->user_data;
+       struct dev_context *devc = sdi->priv;
+       struct libusb_transfer *in_xfer = devc->transfers[11];
+       struct timespec tsample;
+       uint64_t now;
+
+       /* acquisition has already ended */
+       if (devc->sent_samples < 0 || transfer->status == LIBUSB_TRANSFER_NO_DEVICE)
+               goto abort_vbus;
+
+       if (transfer->status != LIBUSB_TRANSFER_COMPLETED)
+               goto abort_vbus;
+
+       clock_gettime(CLOCK_REALTIME, &tsample);
+       now = tsample.tv_nsec + (uint64_t)tsample.tv_sec *1000000000ULL;
+       devc->vbus_delta = now - devc->vbus_t0;
+       devc->vbus_t0 = now;
+       if (libusb_submit_transfer(in_xfer) != LIBUSB_SUCCESS)
+               goto abort_vbus;
+
+       return;
+abort_vbus:
+       libusb_free_transfer(transfer);
+       libusb_free_transfer(in_xfer);
+       devc->transfers[10] = NULL;
+       devc->transfers[11] = NULL;
+       devc->submitted_transfers--;
+       if (devc->submitted_transfers == 0)
+               finish_acquisition(sdi);
+}
+
+SR_PRIV void twinkie_vbus_recv(struct libusb_transfer *transfer)
+{
+       struct sr_dev_inst *sdi = transfer->user_data;
+       struct dev_context *devc = sdi->priv;
+       struct libusb_transfer *out_xfer = devc->transfers[10];
+
+       /* acquisition has already ended */
+       if (devc->sent_samples < 0 || transfer->status == LIBUSB_TRANSFER_NO_DEVICE)
+               goto abort_vbus;
+
+       if (transfer->status == LIBUSB_TRANSFER_COMPLETED &&
+               transfer->actual_length) {
+               int vbus_ma, vbus_mv;
+               int len = transfer->actual_length;
+               if (len > 63)
+                       len = 63;
+               devc->vbus_data[len] = 0;
+               if (sscanf(devc->vbus_data, VBUS_FORMAT, &vbus_mv, &vbus_ma) == 2) {
+                       export_vbus(sdi, vbus_mv, vbus_ma);
+               }
+       }
+
+       if (libusb_submit_transfer(out_xfer) != LIBUSB_SUCCESS)
+               goto abort_vbus;
+
+       return;
+abort_vbus:
+       libusb_free_transfer(transfer);
+       libusb_free_transfer(out_xfer);
+       devc->transfers[10] = NULL;
+       devc->transfers[11] = NULL;
+       devc->submitted_transfers--;
+       if (devc->submitted_transfers == 0)
+               finish_acquisition(sdi);
+}

diff --git a/src/hardware/chromium-twinkie/protocol.h b/src/hardware/chromium-twinkie/protocol.h
index ddf4e8b67d283ada21d3afae910ec0d7b1129b41..dc9a5bb3d305c188a4b640e7258c01f0daeb171c 100644 (file)
--- a/src/hardware/chromium-twinkie/protocol.h
+++ b/src/hardware/chromium-twinkie/protocol.h
@@ -35,6 +35,13 @@ struct cc_context {
        uint8_t level;
 };
 
+enum vbus_group_index {
+       VBUS_V = 0,
+       VBUS_A = 1,
+
+       VBUS_GRP_COUNT = 2
+};
+
 /** Private, per-device-instance driver context. */
 struct dev_context {
        /** Maximum number of samples to capture, if nonzero. */
@@ -50,10 +57,20 @@ struct dev_context {
        struct sr_context *ctx;
 
        struct cc_context cc[2];
+       int vbus_channels;
+       char vbus_data[64];
+       uint64_t vbus_t0;
+       uint64_t vbus_delta;
+        struct sr_datafeed_analog vbus_packet[VBUS_GRP_COUNT];
+        struct sr_analog_meaning vbus_meaning[VBUS_GRP_COUNT];
+        struct sr_analog_encoding vbus_encoding;
+        struct sr_analog_spec vbus_spec;
 };
 
 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 twinkie_receive_transfer(struct libusb_transfer *transfer);
+SR_PRIV void twinkie_vbus_sent(struct libusb_transfer *transfer);
+SR_PRIV void twinkie_vbus_recv(struct libusb_transfer *transfer);
 
 #endif