[libsigrok.git] / src / hardware / baylibre-acme / protocol.c

/*
 * This file is part of the libsigrok project.
 *
 * Copyright (C) 2015 Bartosz Golaszewski <bgolaszewski@baylibre.com>
 *
 * 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 <string.h>
#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>
#include <glib/gstdio.h>
#include "protocol.h"
#include "gpio.h"

enum channel_type {
	ENRG_PWR = 1,
	ENRG_CURR,
	ENRG_VOL,
	TEMP_IN,
	TEMP_OUT,
};

struct channel_group_priv {
	int hwmon_num;
	int probe_type;
	int index;
	int has_pws;
};

struct channel_priv {
	int ch_type;
	int fd;
	float val;
	struct channel_group_priv *probe;
};

static const uint8_t enrg_i2c_addrs[] = {
	0x40, 0x41, 0x44, 0x45, 0x42, 0x43, 0x46, 0x47,
};

static const uint8_t temp_i2c_addrs[] = {
	0x0, 0x0, 0x0, 0x0, 0x4c, 0x49, 0x4f, 0x4b,
};

static const uint32_t pws_gpios[] = {
	486, 498, 502, 482, 478, 506, 510, 474,
};

static const uint32_t pws_info_gpios[] = {
	487, 499, 503, 483, 479, 507, 511, 475,
};

#define MOHM_TO_UOHM(x) ((x) * 1000)
#define UOHM_TO_MOHM(x) ((x) / 1000)

SR_PRIV uint8_t bl_acme_get_enrg_addr(int index)
{
	return enrg_i2c_addrs[index];
}

SR_PRIV uint8_t bl_acme_get_temp_addr(int index)
{
	return temp_i2c_addrs[index];
}

SR_PRIV gboolean bl_acme_is_sane(void)
{
	gboolean status;

	/*
	 * We expect sysfs to be present and mounted at /sys, ina226 and
	 * tmp435 sensors detected by the system and their appropriate
	 * drivers loaded and functional.
	 */
	status = g_file_test("/sys", G_FILE_TEST_IS_DIR);
	if (!status) {
		sr_err("/sys/ directory not found - sysfs not mounted?");
		return FALSE;
	}

	return TRUE;
}

static void probe_name_path(unsigned int addr, GString *path)
{
	g_string_printf(path,
			"/sys/class/i2c-adapter/i2c-1/1-00%02x/name", addr);
}

/*
 * For given address fill buf with the path to appropriate hwmon entry.
 */
static void probe_hwmon_path(unsigned int addr, GString *path)
{
	g_string_printf(path,
			"/sys/class/i2c-adapter/i2c-1/1-00%02x/hwmon", addr);
}

SR_PRIV gboolean bl_acme_detect_probe(unsigned int addr,
				      int prb_num, const char *prb_name)
{
	gboolean ret = FALSE, status;
	char *buf = NULL;
	GString *path = g_string_sized_new(64);
	GError *err = NULL;
	gsize size;

	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);
		g_string_free(path, TRUE);
		return ret;
	}

	if (!strncmp(buf, prb_name, strlen(prb_name))) {
		/*
		 * Correct driver registered on this address - but is
		 * there an actual probe connected?
		 */
		probe_hwmon_path(addr, path);
		status = g_file_test(path->str, G_FILE_TEST_IS_DIR);
		if (status) {
			/* We have found an ACME probe. */
			ret = TRUE;
		}
	}

	g_free(buf);
	g_string_free(path, TRUE);

	return ret;
}

static int get_hwmon_index(unsigned int addr)
{
	int status, hwmon;
	GString *path = g_string_sized_new(64);
	GError *err = NULL;
	GDir *dir;

	probe_hwmon_path(addr, path);
	dir = g_dir_open(path->str, 0, &err);
	if (!dir) {
		sr_err("Error opening %s: %s", path->str, err->message);
		g_string_free(path, TRUE);
		return -1;
	}

	g_string_free(path, TRUE);

	/*
	 * The directory should contain a single file named hwmonX where X
	 * is the hwmon index.
	 */
	status = sscanf(g_dir_read_name(dir), "hwmon%d", &hwmon);
	g_dir_close(dir);
	if (status != 1) {
		sr_err("Unable to determine the hwmon entry");
		return -1;
	}

	return hwmon;
}

static void append_channel(struct sr_dev_inst *sdi, struct sr_channel_group *cg,
			   int index, int type)
{
	struct channel_priv *cp;
	struct dev_context *devc;
	struct sr_channel *ch;
	char *name;

	devc = sdi->priv;

	switch (type) {
	case ENRG_PWR:
		name = g_strdup_printf("P%d_ENRG_PWR", index);
		break;
	case ENRG_CURR:
		name = g_strdup_printf("P%d_ENRG_CURR", index);
		break;
	case ENRG_VOL:
		name = g_strdup_printf("P%d_ENRG_VOL", index);
		break;
	case TEMP_IN:
		name = g_strdup_printf("P%d_TEMP_IN", index);
		break;
	case TEMP_OUT:
		name = g_strdup_printf("P%d_TEMP_OUT", index);
		break;
	default:
		sr_err("Invalid channel type: %d.", type);
		return;
	}

	cp = g_malloc0(sizeof(struct channel_priv));
	cp->ch_type = type;
	cp->probe = cg->priv;

	ch = sr_channel_new(sdi, devc->num_channels++,
			    SR_CHANNEL_ANALOG, TRUE, name);
	g_free(name);

	ch->priv = cp;
	cg->channels = g_slist_append(cg->channels, ch);
}

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;

	/* 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));
	cgp->hwmon_num = hwmon;
	cgp->probe_type = type;
	cgp->index = prb_num - 1;
	cgp->has_pws = sr_gpio_getval_export(pws_info_gpios[cgp->index]);
	cg->name = g_strdup_printf("Probe_%d", prb_num);
	cg->priv = cgp;

	if (type == PROBE_ENRG) {
		append_channel(sdi, cg, prb_num, ENRG_PWR);
		append_channel(sdi, cg, prb_num, ENRG_CURR);
		append_channel(sdi, cg, prb_num, ENRG_VOL);
	} else if (type == PROBE_TEMP) {
		append_channel(sdi, cg, prb_num, TEMP_IN);
		append_channel(sdi, cg, prb_num, TEMP_OUT);
	} else {
		sr_err("Invalid probe type: %d.", type);
	}

	sdi->channel_groups = g_slist_append(sdi->channel_groups, cg);

	return TRUE;
}

SR_PRIV int bl_acme_get_probe_type(const struct sr_channel_group *cg)
{
	struct channel_group_priv *cgp = cg->priv;

	return cgp->probe_type;
}

SR_PRIV int bl_acme_probe_has_pws(const struct sr_channel_group *cg)
{
	struct channel_group_priv *cgp = cg->priv;

	return cgp->has_pws;
}

/*
 * Sets path to the hwmon attribute if this channel group
 * supports shunt resistance setting. The caller has to supply
 * a valid GString.
 */
static int get_shunt_path(const struct sr_channel_group *cg, GString *path)
{
	struct channel_group_priv *cgp;
	int ret = SR_OK, status;

	cgp = cg->priv;

	if (cgp->probe_type != PROBE_ENRG) {
		sr_err("Probe doesn't support shunt resistance setting");
		return SR_ERR_ARG;
	}

	g_string_append_printf(path,
			       "/sys/class/hwmon/hwmon%d/shunt_resistor",
			       cgp->hwmon_num);

	/*
	 * The shunt_resistor sysfs attribute is available
	 * in the Linux kernel since version 3.20. We have
	 * to notify the user if this attribute is not present.
	 */
	status = g_file_test(path->str, G_FILE_TEST_EXISTS);
	if (!status) {
		sr_err("shunt_resistance attribute not present, please update "
		       "your kernel to version >=3.20");
		return SR_ERR_NA;
	}

	return ret;
}

/*
 * Try setting the update_interval sysfs attribute for each probe according
 * to samplerate.
 */
SR_PRIV void bl_acme_maybe_set_update_interval(const struct sr_dev_inst *sdi,
					       uint64_t samplerate)
{
	struct sr_channel_group *cg;
	struct channel_group_priv *cgp;
	GString *hwmon;
	GSList *l;
	FILE *fd;

	for (l = sdi->channel_groups; l != NULL; l = l->next) {
		cg = l->data;
		cgp = cg->priv;

		hwmon = g_string_sized_new(64);
		g_string_append_printf(hwmon,
				"/sys/class/hwmon/hwmon%d/update_interval",
				cgp->hwmon_num);

		if (g_file_test(hwmon->str, G_FILE_TEST_EXISTS)) {
			fd = g_fopen(hwmon->str, "w");
			if (!fd) {
				g_string_free(hwmon, TRUE);
				continue;
			}

			g_fprintf(fd, "%" PRIu64 "\n", 1000 / samplerate);
			fclose(fd);
		}

		g_string_free(hwmon, TRUE);
	}
}

SR_PRIV int bl_acme_get_shunt(const struct sr_channel_group *cg,
			      uint64_t *shunt)
{
	GString *path = g_string_sized_new(64);
	gchar *contents;
	int status, ret = SR_OK;
	GError *err = NULL;

	status = get_shunt_path(cg, path);
	if (status != SR_OK) {
		ret = status;
		goto out;
	}

	status = g_file_get_contents(path->str, &contents, NULL, &err);
	if (!status) {
		sr_err("Error reading shunt resistance: %s", err->message);
		ret = SR_ERR_IO;
		goto out;
	}

	*shunt = UOHM_TO_MOHM(strtol(contents, NULL, 10));

out:
	g_string_free(path, TRUE);
	return ret;
}

SR_PRIV int bl_acme_set_shunt(const struct sr_channel_group *cg, uint64_t shunt)
{
	GString *path = g_string_sized_new(64);;
	int status, ret = SR_OK;
	FILE *fd;

	status = get_shunt_path(cg, path);
	if (status != SR_OK) {
		ret = status;
		goto out;
	}

	/*
	 * Can't use g_file_set_contents() here, as it calls open() with
	 * O_EXEC flag in a sysfs directory thus failing with EACCES.
	 */
	fd = g_fopen(path->str, "w");
	if (!fd) {
		sr_err("Error opening %s: %s", path->str, g_strerror(errno));
		ret = SR_ERR_IO;
		goto out;
	}

	g_fprintf(fd, "%" PRIu64 "\n", MOHM_TO_UOHM(shunt));
	fclose(fd);

out:
	g_string_free(path, TRUE);
	return ret;
}

SR_PRIV int bl_acme_read_power_state(const struct sr_channel_group *cg,
				     gboolean *off)
{
	struct channel_group_priv *cgp;
	int val;

	cgp = cg->priv;

	if (!bl_acme_probe_has_pws(cg)) {
		sr_err("Probe has no power-switch");
		return SR_ERR_ARG;
	}

	val = sr_gpio_getval_export(pws_gpios[cgp->index]);
	*off = val ? FALSE : TRUE;

	return SR_OK;
}

SR_PRIV int bl_acme_set_power_off(const struct sr_channel_group *cg,
				  gboolean off)
{
	struct channel_group_priv *cgp;
	int val;

	cgp = cg->priv;

	if (!bl_acme_probe_has_pws(cg)) {
		sr_err("Probe has no power-switch");
		return SR_ERR_ARG;
	}

	val = sr_gpio_setval_export(pws_gpios[cgp->index], off ? 0 : 1);
	if (val < 0) {
		sr_err("Error setting power-off state: gpio: %d",
		       pws_gpios[cgp->index]);
		return SR_ERR_IO;
	}

	return SR_OK;
}

static int channel_to_mq(struct sr_channel *ch)
{
	struct channel_priv *chp;

	chp = ch->priv;

	switch (chp->ch_type) {
	case ENRG_PWR:
		return SR_MQ_POWER;
	case ENRG_CURR:
		return SR_MQ_CURRENT;
	case ENRG_VOL:
		return SR_MQ_VOLTAGE;
	case TEMP_IN: /* Fallthrough */
	case TEMP_OUT:
		return SR_MQ_TEMPERATURE;
	default:
		return -1;
	}
}

static int channel_to_unit(struct sr_channel *ch)
{
	struct channel_priv *chp;

	chp = ch->priv;

	switch (chp->ch_type) {
	case ENRG_PWR:
		return SR_UNIT_WATT;
	case ENRG_CURR:
		return SR_UNIT_AMPERE;
	case ENRG_VOL:
		return SR_UNIT_VOLT;
	case TEMP_IN: /* Fallthrough */
	case TEMP_OUT:
		return SR_UNIT_CELSIUS;
	default:
		return -1;
	}
}

/* We need to scale measurements down from the units used by the drivers. */
static float adjust_data(int val, int type)
{
	switch (type) {
	case ENRG_PWR:
		return ((float)val) / 1000000.0;
	case ENRG_CURR: /* Fallthrough */
	case ENRG_VOL: /* Fallthrough */
	case TEMP_IN: /* Fallthrough */
	case TEMP_OUT:
		return ((float)val) / 1000.0;
	default:
		return 0.0;
	}
}

static float read_sample(struct sr_channel *ch)
{
	struct channel_priv *chp;
	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;
	}

	return adjust_data(strtol(buf, NULL, 10), chp->ch_type);
}

SR_PRIV int bl_acme_open_channel(struct sr_channel *ch)
{
	struct channel_priv *chp;
	char path[64], *file;
	int fd;

	chp = ch->priv;

	switch (chp->ch_type) {
	case ENRG_PWR:	file = "power1_input";	break;
	case ENRG_CURR:	file = "curr1_input";	break;
	case ENRG_VOL:	file = "in1_input";	break;
	case TEMP_IN:	file = "temp1_input";	break;
	case TEMP_OUT:	file = "temp2_input";	break;
	default:
		sr_err("Invalid channel type: %d.", chp->ch_type);
		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, g_strerror(errno));
		ch->enabled = FALSE;
		return SR_ERR;
	}

	chp->fd = fd;

	return 0;
}

SR_PRIV void bl_acme_close_channel(struct sr_channel *ch)
{
	struct channel_priv *chp;

	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;
	uint64_t nrexpiration;
	struct sr_datafeed_packet packet, framep;
	struct sr_datafeed_analog analog;
	struct sr_dev_inst *sdi;
	struct sr_channel *ch;
	struct channel_priv *chp;
	struct dev_context *devc;
	GSList *chl, chonly;
	unsigned i;

	(void)fd;
	(void)revents;

	sdi = cb_data;
	if (!sdi)
		return TRUE;

	devc = sdi->priv;
	if (!devc)
		return TRUE;

	packet.type = SR_DF_ANALOG;
	packet.payload = &analog;
	memset(&analog, 0, sizeof(struct sr_datafeed_analog));

	if (read(devc->timer_fd, &nrexpiration, sizeof(nrexpiration)) < 0) {
		sr_warn("Failed to read timer information");
		return TRUE;
	}

	/*
	 * We were not able to process the previous timer expiration, we are
	 * overloaded.
	 */
	if (nrexpiration > 1)
		devc->samples_missed += nrexpiration - 1;

	/*
	 * 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 (i = 0; i < nrexpiration; i++) {
		framep.type = SR_DF_FRAME_BEGIN;
		sr_session_send(cb_data, &framep);

		/*
		 * 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.channels = &chonly;
			analog.num_samples = 1;
			analog.mq = channel_to_mq(chl->data);
			analog.unit = channel_to_unit(ch);

			if (i < 1)
				chp->val = read_sample(ch);

			analog.data = &chp->val;
			sr_session_send(cb_data, &packet);
		}

		framep.type = SR_DF_FRAME_END;
		sr_session_send(cb_data, &framep);
	}

	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();
		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;
}
Commit	Line	Data
dfaee1de BG	1	/*
	2	* This file is part of the libsigrok project.
	3	*
	4	* Copyright (C) 2015 Bartosz Golaszewski <bgolaszewski@baylibre.com>
	5	*
	6	* This program is free software: you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation, either version 3 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program. If not, see <http://www.gnu.org/licenses/>.
	18	*/
	19
6ec6c43b	20	#include <config.h>
6b80b80d	21	#include <string.h>
391e23a9	22	#include <stdlib.h>
6b80b80d	23	#include <errno.h>
391e23a9	24	#include <fcntl.h>
61f2b7f7	25	#include <glib/gstdio.h>
dfaee1de	26	#include "protocol.h"
740ad48a	27	#include "gpio.h"
dfaee1de	28
133016f6 BG	29	enum channel_type {
	30	ENRG_PWR = 1,
	31	ENRG_CURR,
	32	ENRG_VOL,
	33	TEMP_IN,
	34	TEMP_OUT,
	35	};
	36
6b80b80d BG	37	struct channel_group_priv {
6b80b80d BG	38	int hwmon_num;
61f2b7f7	39	int probe_type;
740ad48a	40	int index;
8f196120	41	int has_pws;
6b80b80d BG	42	};
	43
	44	struct channel_priv {
	45	int ch_type;
4e88b86c	46	int fd;
7e5a048f	47	float val;
6b80b80d BG	48	struct channel_group_priv *probe;
	49	};
	50
	51	static const uint8_t enrg_i2c_addrs[] = {
	52	0x40, 0x41, 0x44, 0x45, 0x42, 0x43, 0x46, 0x47,
	53	};
	54
	55	static const uint8_t temp_i2c_addrs[] = {
	56	0x0, 0x0, 0x0, 0x0, 0x4c, 0x49, 0x4f, 0x4b,
	57	};
	58
740ad48a	59	static const uint32_t pws_gpios[] = {
391e23a9	60	486, 498, 502, 482, 478, 506, 510, 474,
740ad48a BG	61	};
	62
	63	static const uint32_t pws_info_gpios[] = {
	64	487, 499, 503, 483, 479, 507, 511, 475,
	65	};
	66
61f2b7f7 BG	67	#define MOHM_TO_UOHM(x) ((x) * 1000)
	68	#define UOHM_TO_MOHM(x) ((x) / 1000)
	69
6b80b80d BG	70	SR_PRIV uint8_t bl_acme_get_enrg_addr(int index)
	71	{
	72	return enrg_i2c_addrs[index];
	73	}
	74
	75	SR_PRIV uint8_t bl_acme_get_temp_addr(int index)
	76	{
	77	return temp_i2c_addrs[index];
	78	}
	79
	80	SR_PRIV gboolean bl_acme_is_sane(void)
	81	{
	82	gboolean status;
	83
	84	/*
	85	* We expect sysfs to be present and mounted at /sys, ina226 and
	86	* tmp435 sensors detected by the system and their appropriate
	87	* drivers loaded and functional.
	88	*/
	89	status = g_file_test("/sys", G_FILE_TEST_IS_DIR);
	90	if (!status) {
	91	sr_err("/sys/ directory not found - sysfs not mounted?");
	92	return FALSE;
	93	}
	94
	95	return TRUE;
	96	}
	97
	98	static void probe_name_path(unsigned int addr, GString *path)
	99	{
	100	g_string_printf(path,
	101	"/sys/class/i2c-adapter/i2c-1/1-00%02x/name", addr);
	102	}
	103
	104	/*
	105	* For given address fill buf with the path to appropriate hwmon entry.
	106	*/
	107	static void probe_hwmon_path(unsigned int addr, GString *path)
	108	{
	109	g_string_printf(path,
	110	"/sys/class/i2c-adapter/i2c-1/1-00%02x/hwmon", addr);
	111	}
	112
	113	SR_PRIV gboolean bl_acme_detect_probe(unsigned int addr,
	114	int prb_num, const char *prb_name)
	115	{
	116	gboolean ret = FALSE, status;
	117	char *buf = NULL;
	118	GString *path = g_string_sized_new(64);
	119	GError *err = NULL;
	120	gsize size;
	121
	122	probe_name_path(addr, path);
	123	status = g_file_get_contents(path->str, &buf, &size, &err);
	124	if (!status) {
	125	sr_dbg("Name for probe %d can't be read: %s",
	126	prb_num, err->message);
	127	g_string_free(path, TRUE);
	128	return ret;
6b80b80d BG	129	}
6b80b80d BG	130
391e23a9	131	if (!strncmp(buf, prb_name, strlen(prb_name))) {
6b80b80d BG	132	/*
	133	* Correct driver registered on this address - but is
	134	* there an actual probe connected?
	135	*/
	136	probe_hwmon_path(addr, path);
	137	status = g_file_test(path->str, G_FILE_TEST_IS_DIR);
	138	if (status) {
	139	/* We have found an ACME probe. */
	140	ret = TRUE;
	141	}
	142	}
	143
	144	g_free(buf);
	145	g_string_free(path, TRUE);
	146
	147	return ret;
	148	}
	149
	150	static int get_hwmon_index(unsigned int addr)
	151	{
	152	int status, hwmon;
	153	GString *path = g_string_sized_new(64);
	154	GError *err = NULL;
	155	GDir *dir;
	156
	157	probe_hwmon_path(addr, path);
	158	dir = g_dir_open(path->str, 0, &err);
391e23a9	159	if (!dir) {
6b80b80d BG	160	sr_err("Error opening %s: %s", path->str, err->message);
	161	g_string_free(path, TRUE);
	162	return -1;
	163	}
	164
	165	g_string_free(path, TRUE);
	166
	167	/*
	168	* The directory should contain a single file named hwmonX where X
	169	* is the hwmon index.
	170	*/
	171	status = sscanf(g_dir_read_name(dir), "hwmon%d", &hwmon);
	172	g_dir_close(dir);
	173	if (status != 1) {
	174	sr_err("Unable to determine the hwmon entry");
	175	return -1;
	176	}
	177
	178	return hwmon;
	179	}
	180
391e23a9	181	static void append_channel(struct sr_dev_inst sdi, struct sr_channel_group cg,
6b80b80d BG	182	int index, int type)
	183	{
	184	struct channel_priv *cp;
	185	struct dev_context *devc;
	186	struct sr_channel *ch;
	187	char *name;
	188
	189	devc = sdi->priv;
	190
	191	switch (type) {
	192	case ENRG_PWR:
	193	name = g_strdup_printf("P%d_ENRG_PWR", index);
	194	break;
	195	case ENRG_CURR:
	196	name = g_strdup_printf("P%d_ENRG_CURR", index);
	197	break;
	198	case ENRG_VOL:
	199	name = g_strdup_printf("P%d_ENRG_VOL", index);
	200	break;
	201	case TEMP_IN:
	202	name = g_strdup_printf("P%d_TEMP_IN", index);
	203	break;
	204	case TEMP_OUT:
	205	name = g_strdup_printf("P%d_TEMP_OUT", index);
	206	break;
	207	default:
391e23a9	208	sr_err("Invalid channel type: %d.", type);
6b80b80d BG	209	return;
	210	}
	211
	212	cp = g_malloc0(sizeof(struct channel_priv));
	213	cp->ch_type = type;
	214	cp->probe = cg->priv;
	215
5e23fcab	216	ch = sr_channel_new(sdi, devc->num_channels++,
6b80b80d BG	217	SR_CHANNEL_ANALOG, TRUE, name);
	218	g_free(name);
	219
	220	ch->priv = cp;
	221	cg->channels = g_slist_append(cg->channels, ch);
6b80b80d BG	222	}
	223
	224	SR_PRIV gboolean bl_acme_register_probe(struct sr_dev_inst *sdi, int type,
	225	unsigned int addr, int prb_num)
	226	{
	227	struct sr_channel_group *cg;
	228	struct channel_group_priv *cgp;
	229	int hwmon;
	230
	231	/* Obtain the hwmon index. */
	232	hwmon = get_hwmon_index(addr);
	233	if (hwmon < 0)
	234	return FALSE;
	235
	236	cg = g_malloc0(sizeof(struct sr_channel_group));
	237	cgp = g_malloc0(sizeof(struct channel_group_priv));
	238	cgp->hwmon_num = hwmon;
61f2b7f7	239	cgp->probe_type = type;
740ad48a	240	cgp->index = prb_num - 1;
8f196120	241	cgp->has_pws = sr_gpio_getval_export(pws_info_gpios[cgp->index]);
6b80b80d BG	242	cg->name = g_strdup_printf("Probe_%d", prb_num);
	243	cg->priv = cgp;
	244
	245	if (type == PROBE_ENRG) {
	246	append_channel(sdi, cg, prb_num, ENRG_PWR);
	247	append_channel(sdi, cg, prb_num, ENRG_CURR);
	248	append_channel(sdi, cg, prb_num, ENRG_VOL);
	249	} else if (type == PROBE_TEMP) {
	250	append_channel(sdi, cg, prb_num, TEMP_IN);
	251	append_channel(sdi, cg, prb_num, TEMP_OUT);
	252	} else {
391e23a9	253	sr_err("Invalid probe type: %d.", type);
6b80b80d BG	254	}
	255
	256	sdi->channel_groups = g_slist_append(sdi->channel_groups, cg);
	257
	258	return TRUE;
	259	}
	260
1fe04eb8 BG	261	SR_PRIV int bl_acme_get_probe_type(const struct sr_channel_group *cg)
	262	{
	263	struct channel_group_priv *cgp = cg->priv;
	264
	265	return cgp->probe_type;
	266	}
	267
	268	SR_PRIV int bl_acme_probe_has_pws(const struct sr_channel_group *cg)
	269	{
	270	struct channel_group_priv *cgp = cg->priv;
	271
8f196120	272	return cgp->has_pws;
1fe04eb8 BG	273	}
1fe04eb8 BG	274
61f2b7f7 BG	275	/*
	276	* Sets path to the hwmon attribute if this channel group
	277	* supports shunt resistance setting. The caller has to supply
	278	* a valid GString.
	279	*/
	280	static int get_shunt_path(const struct sr_channel_group cg, GString path)
	281	{
	282	struct channel_group_priv *cgp;
	283	int ret = SR_OK, status;
	284
	285	cgp = cg->priv;
	286
	287	if (cgp->probe_type != PROBE_ENRG) {
	288	sr_err("Probe doesn't support shunt resistance setting");
	289	return SR_ERR_ARG;
	290	}
	291
	292	g_string_append_printf(path,
	293	"/sys/class/hwmon/hwmon%d/shunt_resistor",
	294	cgp->hwmon_num);
	295
	296	/*
	297	* The shunt_resistor sysfs attribute is available
	298	* in the Linux kernel since version 3.20. We have
391e23a9	299	* to notify the user if this attribute is not present.
61f2b7f7 BG	300	*/
	301	status = g_file_test(path->str, G_FILE_TEST_EXISTS);
	302	if (!status) {
391e23a9	303	sr_err("shunt_resistance attribute not present, please update "
61f2b7f7 BG	304	"your kernel to version >=3.20");
	305	return SR_ERR_NA;
	306	}
	307
	308	return ret;
	309	}
	310
7c91c22a BG	311	/*
	312	* Try setting the update_interval sysfs attribute for each probe according
	313	* to samplerate.
	314	*/
	315	SR_PRIV void bl_acme_maybe_set_update_interval(const struct sr_dev_inst *sdi,
	316	uint64_t samplerate)
	317	{
	318	struct sr_channel_group *cg;
	319	struct channel_group_priv *cgp;
	320	GString *hwmon;
	321	GSList *l;
	322	FILE *fd;
	323
	324	for (l = sdi->channel_groups; l != NULL; l = l->next) {
	325	cg = l->data;
	326	cgp = cg->priv;
	327
	328	hwmon = g_string_sized_new(64);
	329	g_string_append_printf(hwmon,
	330	"/sys/class/hwmon/hwmon%d/update_interval",
	331	cgp->hwmon_num);
	332
	333	if (g_file_test(hwmon->str, G_FILE_TEST_EXISTS)) {
	334	fd = g_fopen(hwmon->str, "w");
	335	if (!fd) {
	336	g_string_free(hwmon, TRUE);
	337	continue;
	338	}
	339
	340	g_fprintf(fd, "%" PRIu64 "\n", 1000 / samplerate);
	341	fclose(fd);
	342	}
	343
	344	g_string_free(hwmon, TRUE);
	345	}
	346	}
	347
61f2b7f7 BG	348	SR_PRIV int bl_acme_get_shunt(const struct sr_channel_group *cg,
	349	uint64_t *shunt)
	350	{
	351	GString *path = g_string_sized_new(64);
	352	gchar *contents;
	353	int status, ret = SR_OK;
	354	GError *err = NULL;
	355
	356	status = get_shunt_path(cg, path);
	357	if (status != SR_OK) {
	358	ret = status;
	359	goto out;
	360	}
	361
	362	status = g_file_get_contents(path->str, &contents, NULL, &err);
	363	if (!status) {
	364	sr_err("Error reading shunt resistance: %s", err->message);
	365	ret = SR_ERR_IO;
	366	goto out;
	367	}
	368
	369	*shunt = UOHM_TO_MOHM(strtol(contents, NULL, 10));
	370
	371	out:
	372	g_string_free(path, TRUE);
	373	return ret;
	374	}
	375
391e23a9	376	SR_PRIV int bl_acme_set_shunt(const struct sr_channel_group *cg, uint64_t shunt)
61f2b7f7 BG	377	{
	378	GString *path = g_string_sized_new(64);;
	379	int status, ret = SR_OK;
	380	FILE *fd;
	381
	382	status = get_shunt_path(cg, path);
	383	if (status != SR_OK) {
	384	ret = status;
	385	goto out;
	386	}
	387
	388	/*
	389	* Can't use g_file_set_contents() here, as it calls open() with
	390	* O_EXEC flag in a sysfs directory thus failing with EACCES.
	391	*/
	392	fd = g_fopen(path->str, "w");
	393	if (!fd) {
7237e912	394	sr_err("Error opening %s: %s", path->str, g_strerror(errno));
350b8b07 BG	395	ret = SR_ERR_IO;
350b8b07 BG	396	goto out;
61f2b7f7 BG	397	}
61f2b7f7 BG	398
34527854	399	g_fprintf(fd, "%" PRIu64 "\n", MOHM_TO_UOHM(shunt));
61f2b7f7 BG	400	fclose(fd);
	401
	402	out:
	403	g_string_free(path, TRUE);
	404	return ret;
	405	}
	406
740ad48a BG	407	SR_PRIV int bl_acme_read_power_state(const struct sr_channel_group *cg,
	408	gboolean *off)
	409	{
	410	struct channel_group_priv *cgp;
	411	int val;
	412
	413	cgp = cg->priv;
	414
1fe04eb8	415	if (!bl_acme_probe_has_pws(cg)) {
740ad48a BG	416	sr_err("Probe has no power-switch");
	417	return SR_ERR_ARG;
	418	}
	419
	420	val = sr_gpio_getval_export(pws_gpios[cgp->index]);
	421	*off = val ? FALSE : TRUE;
	422
	423	return SR_OK;
	424	}
	425
	426	SR_PRIV int bl_acme_set_power_off(const struct sr_channel_group *cg,
	427	gboolean off)
	428	{
	429	struct channel_group_priv *cgp;
09d217a4	430	int val;
740ad48a BG	431
	432	cgp = cg->priv;
	433
1fe04eb8	434	if (!bl_acme_probe_has_pws(cg)) {
740ad48a BG	435	sr_err("Probe has no power-switch");
	436	return SR_ERR_ARG;
	437	}
	438
09d217a4	439	val = sr_gpio_setval_export(pws_gpios[cgp->index], off ? 0 : 1);
192d37e7 BG	440	if (val < 0) {
	441	sr_err("Error setting power-off state: gpio: %d",
	442	pws_gpios[cgp->index]);
	443	return SR_ERR_IO;
	444	}
740ad48a BG	445
	446	return SR_OK;
	447	}
	448
6b80b80d	449	static int channel_to_mq(struct sr_channel *ch)
dfaee1de	450	{
6b80b80d BG	451	struct channel_priv *chp;
	452
	453	chp = ch->priv;
	454
	455	switch (chp->ch_type) {
	456	case ENRG_PWR:
	457	return SR_MQ_POWER;
	458	case ENRG_CURR:
	459	return SR_MQ_CURRENT;
	460	case ENRG_VOL:
	461	return SR_MQ_VOLTAGE;
391e23a9	462	case TEMP_IN: /* Fallthrough */
6b80b80d BG	463	case TEMP_OUT:
	464	return SR_MQ_TEMPERATURE;
	465	default:
	466	return -1;
	467	}
	468	}
	469
	470	static int channel_to_unit(struct sr_channel *ch)
	471	{
	472	struct channel_priv *chp;
	473
	474	chp = ch->priv;
	475
	476	switch (chp->ch_type) {
	477	case ENRG_PWR:
	478	return SR_UNIT_WATT;
	479	case ENRG_CURR:
	480	return SR_UNIT_AMPERE;
	481	case ENRG_VOL:
	482	return SR_UNIT_VOLT;
391e23a9	483	case TEMP_IN: /* Fallthrough */
6b80b80d BG	484	case TEMP_OUT:
	485	return SR_UNIT_CELSIUS;
	486	default:
	487	return -1;
	488	}
	489	}
	490
	491	/* We need to scale measurements down from the units used by the drivers. */
	492	static float adjust_data(int val, int type)
	493	{
	494	switch (type) {
	495	case ENRG_PWR:
	496	return ((float)val) / 1000000.0;
391e23a9 UH	497	case ENRG_CURR: /* Fallthrough */
	498	case ENRG_VOL: /* Fallthrough */
	499	case TEMP_IN: /* Fallthrough */
6b80b80d BG	500	case TEMP_OUT:
	501	return ((float)val) / 1000.0;
	502	default:
	503	return 0.0;
	504	}
	505	}
	506
	507	static float read_sample(struct sr_channel *ch)
	508	{
	509	struct channel_priv *chp;
4e88b86c	510	char buf[16];
6b80b80d BG	511	ssize_t len;
	512	int fd;
	513
4e88b86c DL	514	chp = ch->priv;
	515	fd = chp->fd;
	516
	517	lseek(fd, 0, SEEK_SET);
	518
	519	len = read(fd, buf, sizeof(buf));
	520	if (len < 0) {
6433156c	521	sr_err("Error reading from channel %s (hwmon: %d): %s",
7237e912	522	ch->name, chp->probe->hwmon_num, g_strerror(errno));
4e88b86c DL	523	ch->enabled = FALSE;
	524	return -1.0;
	525	}
	526
	527	return adjust_data(strtol(buf, NULL, 10), chp->ch_type);
	528	}
	529
	530	SR_PRIV int bl_acme_open_channel(struct sr_channel *ch)
	531	{
	532	struct channel_priv *chp;
	533	char path[64], *file;
	534	int fd;
	535
6b80b80d BG	536	chp = ch->priv;
	537
	538	switch (chp->ch_type) {
	539	case ENRG_PWR: file = "power1_input"; break;
	540	case ENRG_CURR: file = "curr1_input"; break;
	541	case ENRG_VOL: file = "in1_input"; break;
	542	case TEMP_IN: file = "temp1_input"; break;
	543	case TEMP_OUT: file = "temp2_input"; break;
	544	default:
391e23a9	545	sr_err("Invalid channel type: %d.", chp->ch_type);
4e88b86c	546	return SR_ERR;
6b80b80d BG	547	}
6b80b80d BG	548
391e23a9	549	snprintf(path, sizeof(path), "/sys/class/hwmon/hwmon%d/%s",
6b80b80d	550	chp->probe->hwmon_num, file);
4e88b86c	551
6b80b80d BG	552	fd = open(path, O_RDONLY);
6b80b80d BG	553	if (fd < 0) {
7237e912	554	sr_err("Error opening %s: %s", path, g_strerror(errno));
6b80b80d	555	ch->enabled = FALSE;
4e88b86c	556	return SR_ERR;
6b80b80d BG	557	}
6b80b80d BG	558
4e88b86c	559	chp->fd = fd;
6b80b80d	560
4e88b86c DL	561	return 0;
	562	}
	563
	564	SR_PRIV void bl_acme_close_channel(struct sr_channel *ch)
	565	{
	566	struct channel_priv *chp;
	567
	568	chp = ch->priv;
	569	close(chp->fd);
	570	chp->fd = -1;
6b80b80d BG	571	}
	572
	573	SR_PRIV int bl_acme_receive_data(int fd, int revents, void *cb_data)
	574	{
a0648b1a DL	575	uint32_t cur_time, elapsed_time;
a0648b1a DL	576	uint64_t nrexpiration;
6b80b80d BG	577	struct sr_datafeed_packet packet, framep;
	578	struct sr_datafeed_analog analog;
	579	struct sr_dev_inst *sdi;
	580	struct sr_channel *ch;
7e5a048f	581	struct channel_priv *chp;
dfaee1de	582	struct dev_context *devc;
6b80b80d	583	GSList *chl, chonly;
7e5a048f	584	unsigned i;
dfaee1de BG	585
dfaee1de BG	586	(void)fd;
6b80b80d BG	587	(void)revents;
	588
	589	sdi = cb_data;
	590	if (!sdi)
	591	return TRUE;
dfaee1de	592
6b80b80d BG	593	devc = sdi->priv;
6b80b80d BG	594	if (!devc)
dfaee1de BG	595	return TRUE;
dfaee1de BG	596
6b80b80d BG	597	packet.type = SR_DF_ANALOG;
6b80b80d BG	598	packet.payload = &analog;
d0148a50	599	memset(&analog, 0, sizeof(struct sr_datafeed_analog));
6b80b80d	600
a0648b1a DL	601	if (read(devc->timer_fd, &nrexpiration, sizeof(nrexpiration)) < 0) {
	602	sr_warn("Failed to read timer information");
	603	return TRUE;
	604	}
	605
6b80b80d	606	/*
a0648b1a DL	607	* We were not able to process the previous timer expiration, we are
a0648b1a DL	608	* overloaded.
6b80b80d	609	*/
a0648b1a DL	610	if (nrexpiration > 1)
a0648b1a DL	611	devc->samples_missed += nrexpiration - 1;
6b80b80d	612
6b80b80d	613	/*
7e5a048f BG	614	* XXX This is a nasty workaround...
	615	*
	616	* At high sampling rates and maximum channels we are not able to
	617	* acquire samples fast enough, even though frontends still think
	618	* that samples arrive on time. This causes shifts in frontend
	619	* plots.
	620	*
	621	* To compensate for the delay we check if any clock events were
	622	* missed and - if so - don't really read the next value, but send
	623	* the same sample as fast as possible. We do it until we are back
	624	* on schedule.
	625	*
	626	* At high sampling rate this doesn't seem to visibly reduce the
	627	* accuracy.
6b80b80d	628	*/
7e5a048f BG	629	for (i = 0; i < nrexpiration; i++) {
	630	framep.type = SR_DF_FRAME_BEGIN;
	631	sr_session_send(cb_data, &framep);
	632
	633	/*
	634	* Due to different units used in each channel we're sending
	635	* samples one-by-one.
	636	*/
	637	for (chl = sdi->channels; chl; chl = chl->next) {
	638	ch = chl->data;
	639	chp = ch->priv;
6b80b80d	640
7e5a048f BG	641	if (!ch->enabled)
	642	continue;
	643	chonly.next = NULL;
	644	chonly.data = ch;
	645	analog.channels = &chonly;
	646	analog.num_samples = 1;
	647	analog.mq = channel_to_mq(chl->data);
	648	analog.unit = channel_to_unit(ch);
	649
	650	if (i < 1)
	651	chp->val = read_sample(ch);
	652
	653	analog.data = &chp->val;
	654	sr_session_send(cb_data, &packet);
	655	}
	656
	657	framep.type = SR_DF_FRAME_END;
	658	sr_session_send(cb_data, &framep);
	659	}
6b80b80d BG	660
	661	devc->samples_read++;
	662	if (devc->limit_samples > 0 &&
	663	devc->samples_read >= devc->limit_samples) {
	664	sr_info("Requested number of samples reached.");
	665	sdi->driver->dev_acquisition_stop(sdi, cb_data);
	666	devc->last_sample_fin = g_get_monotonic_time();
dfaee1de	667	return TRUE;
6b80b80d BG	668	} else if (devc->limit_msec > 0) {
	669	cur_time = g_get_monotonic_time();
	670	elapsed_time = cur_time - devc->start_time;
dfaee1de	671
6b80b80d BG	672	if (elapsed_time >= devc->limit_msec) {
	673	sr_info("Sampling time limit reached.");
	674	sdi->driver->dev_acquisition_stop(sdi, cb_data);
	675	devc->last_sample_fin = g_get_monotonic_time();
	676	return TRUE;
	677	}
dfaee1de BG	678	}
dfaee1de BG	679
6b80b80d	680	devc->last_sample_fin = g_get_monotonic_time();
dfaee1de BG	681	return TRUE;
dfaee1de BG	682	}