]> sigrok.org Git - libsigrok.git/blobdiff - src/hardware/baylibre-acme/protocol.c
output/csv: use intermediate time_t var, silence compiler warning
[libsigrok.git] / src / hardware / baylibre-acme / protocol.c
index d0552553feffbebdb298cba9c1c848e0d87de1e8..8d23b9e2f9875d36093115c52b1911c3e1ac1e2a 100644 (file)
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <config.h>
+#include <math.h>
 #include <string.h>
 #include <stdlib.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <arpa/inet.h>
 #include <glib/gstdio.h>
 #include "protocol.h"
 #include "gpio.h"
 
+#define ACME_REV_A             1
+#define ACME_REV_B             2
+
+enum channel_type {
+       ENRG_PWR = 1,
+       ENRG_CURR,
+       ENRG_VOL,
+       TEMP_IN,
+       TEMP_OUT,
+};
+
 struct channel_group_priv {
+       uint8_t rev;
        int hwmon_num;
        int probe_type;
        int index;
+       int has_pws;
+       uint32_t pws_gpio;
 };
 
 struct channel_priv {
        int ch_type;
+       int fd;
+       int digits;
+       float val;
        struct channel_group_priv *probe;
 };
 
+#define EEPROM_SERIAL_SIZE             16
+#define EEPROM_TAG_SIZE                        32
+
+#define EEPROM_PROBE_TYPE_USB          1
+#define EEPROM_PROBE_TYPE_JACK         2
+#define EEPROM_PROBE_TYPE_HE10         3
+
+struct probe_eeprom {
+       uint32_t type;
+       uint32_t rev;
+       uint32_t shunt;
+       uint8_t pwr_sw;
+       uint8_t serial[EEPROM_SERIAL_SIZE];
+       int8_t tag[EEPROM_TAG_SIZE];
+};
+
+#define EEPROM_SIZE (3 * sizeof(uint32_t) + 1 + EEPROM_SERIAL_SIZE + EEPROM_TAG_SIZE)
+
+#define EEPROM_OFF_TYPE                0
+#define EEPROM_OFF_REV         sizeof(uint32_t)
+#define EEPROM_OFF_SHUNT       (2 * sizeof(uint32_t))
+#define EEPROM_OFF_PWR_SW      (3 * sizeof(uint32_t))
+#define EEPROM_OFF_SERIAL      (3 * sizeof(uint32_t) + 1)
+#define EEPROM_OFF_TAG         (EEPROM_OFF_SERIAL + EEPROM_SERIAL_SIZE)
+
 static const uint8_t enrg_i2c_addrs[] = {
        0x40, 0x41, 0x44, 0x45, 0x42, 0x43, 0x46, 0x47,
 };
@@ -44,14 +89,18 @@ static const uint8_t temp_i2c_addrs[] = {
        0x0, 0x0, 0x0, 0x0, 0x4c, 0x49, 0x4f, 0x4b,
 };
 
-static const uint32_t pws_gpios[] = {
+static const uint32_t revA_pws_gpios[] = {
        486, 498, 502, 482, 478, 506, 510, 474,
 };
 
-static const uint32_t pws_info_gpios[] = {
+static const uint32_t revA_pws_info_gpios[] = {
        487, 499, 503, 483, 479, 507, 511, 475,
 };
 
+static const uint32_t revB_pws_gpios[] = {
+       489, 491, 493, 495, 497, 499, 501, 503,
+};
+
 #define MOHM_TO_UOHM(x) ((x) * 1000)
 #define UOHM_TO_MOHM(x) ((x) / 1000)
 
@@ -98,6 +147,13 @@ static void probe_hwmon_path(unsigned int addr, GString *path)
                        "/sys/class/i2c-adapter/i2c-1/1-00%02x/hwmon", addr);
 }
 
+static void probe_eeprom_path(unsigned int addr, GString *path)
+{
+       g_string_printf(path,
+                       "/sys/class/i2c-dev/i2c-1/device/1-00%02x/eeprom",
+                       addr + 0x10);
+}
+
 SR_PRIV gboolean bl_acme_detect_probe(unsigned int addr,
                                      int prb_num, const char *prb_name)
 {
@@ -110,9 +166,12 @@ SR_PRIV gboolean bl_acme_detect_probe(unsigned int addr,
        probe_name_path(addr, path);
        status = g_file_get_contents(path->str, &buf, &size, &err);
        if (!status) {
-               sr_dbg("Name for probe %d can't be read: %s",
-                      prb_num, err->message);
+               /* Don't log "No such file or directory" messages. */
+               if (err->code != G_FILE_ERROR_NOENT)
+                       sr_dbg("Name for probe %d can't be read (%d): %s",
+                              prb_num, err->code, err->message);
                g_string_free(path, TRUE);
+               g_error_free(err);
                return ret;
        }
 
@@ -147,6 +206,7 @@ static int get_hwmon_index(unsigned int addr)
        if (!dir) {
                sr_err("Error opening %s: %s", path->str, err->message);
                g_string_free(path, TRUE);
+               g_error_free(err);
                return -1;
        }
 
@@ -209,25 +269,104 @@ static void append_channel(struct sr_dev_inst *sdi, struct sr_channel_group *cg,
        cg->channels = g_slist_append(cg->channels, ch);
 }
 
+static int read_probe_eeprom(unsigned int addr, struct probe_eeprom *eeprom)
+{
+       GString *path = g_string_sized_new(64);
+       char eeprom_buf[EEPROM_SIZE];
+       ssize_t rd;
+       int fd;
+
+       probe_eeprom_path(addr, path);
+       fd = g_open(path->str, O_RDONLY);
+       g_string_free(path, TRUE);
+       if (fd < 0)
+               return -1;
+
+       rd = read(fd, eeprom_buf, EEPROM_SIZE);
+       close(fd);
+       if (rd != EEPROM_SIZE)
+               return -1;
+
+       eeprom->type = RB32(eeprom_buf + EEPROM_OFF_TYPE);
+       eeprom->rev = RB32(eeprom_buf + EEPROM_OFF_REV);
+       eeprom->shunt = RB32(eeprom_buf + EEPROM_OFF_SHUNT);
+       eeprom->pwr_sw = R8(eeprom_buf + EEPROM_OFF_PWR_SW);
+       /* Don't care about the serial number and tag for now. */
+
+       /* Check if we have some sensible values. */
+       if (eeprom->rev != 'B')
+               /* 'B' is the only supported revision with EEPROM for now. */
+               return -1;
+
+       if (eeprom->type != EEPROM_PROBE_TYPE_USB &&
+           eeprom->type != EEPROM_PROBE_TYPE_JACK &&
+           eeprom->type != EEPROM_PROBE_TYPE_HE10)
+               return -1;
+
+       return 0;
+}
+
+/* Some i2c slave addresses on revision B probes differ from revision A. */
+static int revB_addr_to_num(unsigned int addr)
+{
+       switch (addr) {
+       case 0x44: return 5;
+       case 0x45: return 6;
+       case 0x42: return 3;
+       case 0x43: return 4;
+       default:   return addr - 0x3f;
+       }
+}
+
 SR_PRIV gboolean bl_acme_register_probe(struct sr_dev_inst *sdi, int type,
                                        unsigned int addr, int prb_num)
 {
        struct sr_channel_group *cg;
        struct channel_group_priv *cgp;
-       int hwmon;
+       struct probe_eeprom eeprom;
+       int hwmon, status;
+       uint32_t gpio;
 
        /* Obtain the hwmon index. */
        hwmon = get_hwmon_index(addr);
        if (hwmon < 0)
                return FALSE;
 
-       cg = g_malloc0(sizeof(struct sr_channel_group));
        cgp = g_malloc0(sizeof(struct channel_group_priv));
+       cg = sr_channel_group_new(sdi, NULL, cgp);
+
+       /*
+        * See if we can read the EEPROM contents. If not, assume it's
+        * a revision A probe.
+        */
+       memset(&eeprom, 0, sizeof(struct probe_eeprom));
+       status = read_probe_eeprom(addr, &eeprom);
+       cgp->rev = status < 0 ? ACME_REV_A : ACME_REV_B;
+
+       prb_num = cgp->rev == ACME_REV_A ? prb_num : revB_addr_to_num(addr);
+
        cgp->hwmon_num = hwmon;
        cgp->probe_type = type;
        cgp->index = prb_num - 1;
        cg->name = g_strdup_printf("Probe_%d", prb_num);
-       cg->priv = cgp;
+
+       if (cgp->rev == ACME_REV_A) {
+               gpio = revA_pws_info_gpios[cgp->index];
+               cgp->has_pws = sr_gpio_getval_export(gpio);
+               cgp->pws_gpio = revA_pws_gpios[cgp->index];
+       } else {
+               cgp->has_pws = eeprom.pwr_sw;
+               cgp->pws_gpio = revB_pws_gpios[cgp->index];
+
+               /*
+                * For revision B we can already try to set the shunt
+                * resistance according to the EEPROM contents.
+                *
+                * Keep the default value if shunt in EEPROM == 0.
+                */
+               if (eeprom.shunt > 0)
+                       bl_acme_set_shunt(cg, UOHM_TO_MOHM(eeprom.shunt));
+       }
 
        if (type == PROBE_ENRG) {
                append_channel(sdi, cg, prb_num, ENRG_PWR);
@@ -240,8 +379,6 @@ SR_PRIV gboolean bl_acme_register_probe(struct sr_dev_inst *sdi, int type,
                sr_err("Invalid probe type: %d.", type);
        }
 
-       sdi->channel_groups = g_slist_append(sdi->channel_groups, cg);
-
        return TRUE;
 }
 
@@ -256,7 +393,7 @@ SR_PRIV int bl_acme_probe_has_pws(const struct sr_channel_group *cg)
 {
        struct channel_group_priv *cgp = cg->priv;
 
-       return sr_gpio_getval_export(pws_info_gpios[cgp->index]);
+       return cgp->has_pws;
 }
 
 /*
@@ -350,6 +487,7 @@ SR_PRIV int bl_acme_get_shunt(const struct sr_channel_group *cg,
        if (!status) {
                sr_err("Error reading shunt resistance: %s", err->message);
                ret = SR_ERR_IO;
+               g_error_free(err);
                goto out;
        }
 
@@ -378,7 +516,7 @@ SR_PRIV int bl_acme_set_shunt(const struct sr_channel_group *cg, uint64_t shunt)
         */
        fd = g_fopen(path->str, "w");
        if (!fd) {
-               sr_err("Error opening %s: %s", path->str, strerror(errno));
+               sr_err("Error opening %s: %s", path->str, g_strerror(errno));
                ret = SR_ERR_IO;
                goto out;
        }
@@ -404,7 +542,7 @@ SR_PRIV int bl_acme_read_power_state(const struct sr_channel_group *cg,
                return SR_ERR_ARG;
        }
 
-       val = sr_gpio_getval_export(pws_gpios[cgp->index]);
+       val = sr_gpio_getval_export(cgp->pws_gpio);
        *off = val ? FALSE : TRUE;
 
        return SR_OK;
@@ -423,7 +561,12 @@ SR_PRIV int bl_acme_set_power_off(const struct sr_channel_group *cg,
                return SR_ERR_ARG;
        }
 
-       val = sr_gpio_setval_export(pws_gpios[cgp->index], off ? 0 : 1);
+       val = sr_gpio_setval_export(cgp->pws_gpio, off ? 0 : 1);
+       if (val < 0) {
+               sr_err("Error setting power-off state: gpio: %d",
+                      cgp->pws_gpio);
+               return SR_ERR_IO;
+       }
 
        return SR_OK;
 }
@@ -471,28 +614,52 @@ static int channel_to_unit(struct sr_channel *ch)
 }
 
 /* We need to scale measurements down from the units used by the drivers. */
-static float adjust_data(int val, int type)
+static int type_digits(int type)
 {
        switch (type) {
        case ENRG_PWR:
-               return ((float)val) / 1000000.0;
+               return 6;
        case ENRG_CURR: /* Fallthrough */
        case ENRG_VOL: /* Fallthrough */
        case TEMP_IN: /* Fallthrough */
        case TEMP_OUT:
-               return ((float)val) / 1000.0;
+               return 3;
        default:
-               return 0.0;
+               return 0;
        }
 }
 
 static float read_sample(struct sr_channel *ch)
 {
        struct channel_priv *chp;
-       char path[64], *file, buf[16];
+       char buf[16];
        ssize_t len;
        int fd;
 
+       chp = ch->priv;
+       fd = chp->fd;
+
+       lseek(fd, 0, SEEK_SET);
+
+       len = read(fd, buf, sizeof(buf));
+       if (len < 0) {
+               sr_err("Error reading from channel %s (hwmon: %d): %s",
+                       ch->name, chp->probe->hwmon_num, g_strerror(errno));
+               ch->enabled = FALSE;
+               return -1.0;
+       }
+
+       chp->digits = type_digits(chp->ch_type);
+       return strtol(buf, NULL, 10) * powf(10, -chp->digits);
+}
+
+SR_PRIV int bl_acme_open_channel(struct sr_channel *ch)
+{
+       struct channel_priv *chp;
+       char path[64];
+       const char *file;
+       int fd;
+
        chp = ch->priv;
 
        switch (chp->ch_type) {
@@ -503,40 +670,47 @@ static float read_sample(struct sr_channel *ch)
        case TEMP_OUT:  file = "temp2_input";   break;
        default:
                sr_err("Invalid channel type: %d.", chp->ch_type);
-               return -1.0;
+               return SR_ERR;
        }
 
        snprintf(path, sizeof(path), "/sys/class/hwmon/hwmon%d/%s",
                 chp->probe->hwmon_num, file);
+
        fd = open(path, O_RDONLY);
        if (fd < 0) {
-               sr_err("Error opening %s: %s", path, strerror(errno));
+               sr_err("Error opening %s: %s", path, g_strerror(errno));
                ch->enabled = FALSE;
-               return -1.0;
+               return SR_ERR;
        }
 
-       len = read(fd, buf, sizeof(buf));
-       close(fd);
-       if (len < 0) {
-               sr_err("Error reading from %s: %s", path, strerror(errno));
-               ch->enabled = FALSE;
-               return -1.0;
-       }
+       chp->fd = fd;
+
+       return 0;
+}
+
+SR_PRIV void bl_acme_close_channel(struct sr_channel *ch)
+{
+       struct channel_priv *chp;
 
-       return adjust_data(strtol(buf, NULL, 10), chp->ch_type);
+       chp = ch->priv;
+       close(chp->fd);
+       chp->fd = -1;
 }
 
 SR_PRIV int bl_acme_receive_data(int fd, int revents, void *cb_data)
 {
-       uint32_t cur_time, elapsed_time, diff_time;
-       int64_t time_to_sleep;
-       struct sr_datafeed_packet packet, framep;
+       uint64_t nrexpiration;
+       struct sr_datafeed_packet packet;
        struct sr_datafeed_analog analog;
+       struct sr_analog_encoding encoding;
+       struct sr_analog_meaning meaning;
+       struct sr_analog_spec spec;
        struct sr_dev_inst *sdi;
        struct sr_channel *ch;
+       struct channel_priv *chp;
        struct dev_context *devc;
        GSList *chl, chonly;
-       float valf;
+       unsigned i;
 
        (void)fd;
        (void)revents;
@@ -551,65 +725,74 @@ SR_PRIV int bl_acme_receive_data(int fd, int revents, void *cb_data)
 
        packet.type = SR_DF_ANALOG;
        packet.payload = &analog;
-       memset(&analog, 0, sizeof(struct sr_datafeed_analog));
-       analog.data = &valf;
+       sr_analog_init(&analog, &encoding, &meaning, &spec, 0);
 
-       /*
-        * Reading from sysfs takes some time - try to keep up with samplerate.
-        */
-       if (devc->samples_read) {
-               cur_time = g_get_monotonic_time();
-               diff_time = cur_time - devc->last_sample_fin;
-               time_to_sleep = G_USEC_PER_SEC / devc->samplerate - diff_time;
-               if (time_to_sleep > 0)
-                       g_usleep(time_to_sleep);
+       if (read(devc->timer_fd, &nrexpiration, sizeof(nrexpiration)) < 0) {
+               sr_warn("Failed to read timer information");
+               return TRUE;
        }
 
-       framep.type = SR_DF_FRAME_BEGIN;
-       sr_session_send(cb_data, &framep);
+       /*
+        * We were not able to process the previous timer expiration, we are
+        * overloaded.
+        */
+       if (nrexpiration > 1)
+               devc->samples_missed += nrexpiration - 1;
 
        /*
-        * Due to different units used in each channel we're sending
-        * samples one-by-one.
+        * XXX This is a nasty workaround...
+        *
+        * At high sampling rates and maximum channels we are not able to
+        * acquire samples fast enough, even though frontends still think
+        * that samples arrive on time. This causes shifts in frontend
+        * plots.
+        *
+        * To compensate for the delay we check if any clock events were
+        * missed and - if so - don't really read the next value, but send
+        * the same sample as fast as possible. We do it until we are back
+        * on schedule.
+        *
+        * At high sampling rate this doesn't seem to visibly reduce the
+        * accuracy.
         */
-       for (chl = sdi->channels; chl; chl = chl->next) {
-               ch = chl->data;
-               if (!ch->enabled)
-                       continue;
-               chonly.next = NULL;
-               chonly.data = ch;
-               analog.channels = &chonly;
-               analog.num_samples = 1;
-               analog.mq = channel_to_mq(chl->data);
-               analog.unit = channel_to_unit(ch);
-
-               valf = read_sample(ch);
-
-               sr_session_send(cb_data, &packet);
+       for (i = 0; i < nrexpiration; i++) {
+               std_session_send_df_frame_begin(sdi);
+
+               /*
+                * Due to different units used in each channel we're sending
+                * samples one-by-one.
+                */
+               for (chl = sdi->channels; chl; chl = chl->next) {
+                       ch = chl->data;
+                       chp = ch->priv;
+
+                       if (!ch->enabled)
+                               continue;
+                       chonly.next = NULL;
+                       chonly.data = ch;
+                       analog.num_samples = 1;
+                       analog.meaning->channels = &chonly;
+                       analog.meaning->mq = channel_to_mq(chl->data);
+                       analog.meaning->unit = channel_to_unit(ch);
+
+                       if (i < 1)
+                               chp->val = read_sample(ch);
+
+                       analog.encoding->digits  = chp->digits;
+                       analog.spec->spec_digits = chp->digits;
+                       analog.data = &chp->val;
+                       sr_session_send(sdi, &packet);
+               }
+
+               std_session_send_df_frame_end(sdi);
        }
 
-       framep.type = SR_DF_FRAME_END;
-       sr_session_send(cb_data, &framep);
+       sr_sw_limits_update_samples_read(&devc->limits, 1);
 
-       devc->samples_read++;
-       if (devc->limit_samples > 0 &&
-           devc->samples_read >= devc->limit_samples) {
-               sr_info("Requested number of samples reached.");
-               sdi->driver->dev_acquisition_stop(sdi, cb_data);
-               devc->last_sample_fin = g_get_monotonic_time();
+       if (sr_sw_limits_check(&devc->limits)) {
+               sr_dev_acquisition_stop(sdi);
                return TRUE;
-       } else if (devc->limit_msec > 0) {
-               cur_time = g_get_monotonic_time();
-               elapsed_time = cur_time - devc->start_time;
-
-               if (elapsed_time >= devc->limit_msec) {
-                       sr_info("Sampling time limit reached.");
-                       sdi->driver->dev_acquisition_stop(sdi, cb_data);
-                       devc->last_sample_fin = g_get_monotonic_time();
-                       return TRUE;
-               }
        }
 
-       devc->last_sample_fin = g_get_monotonic_time();
        return TRUE;
 }