Console command for g781 temperature sensor.

Read status, set temperature alert thresholds, get and set
configuration options. I2c offsets and status/config register
bits are documented in temp_sensor_g781.h

Usage by example:
g781 - Print status info
g781 settemp 0x0e 12 - Set remote low temp alarm to 12C
g781 setbyte 0x09 0x40 - Enable single-shot mode
g781 getbyte 0xfe - Read device ID

BUG=None
BRANCH=falco,peppy
TEST=Manual. Run g781 console command

Signed-off-by: Dave Parker <dparker@chromium.org>

Change-Id: Id051f79ea643255d57c3fc694b7ae685a6611c81
Reviewed-on: https://gerrit.chromium.org/gerrit/65234
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Commit-Queue: Dave Parker <dparker@chromium.org>
Tested-by: Dave Parker <dparker@chromium.org>

common/temp_sensor_g781.c

@@ -9,37 +9,179 @@
 #include "console.h"
 #include "i2c.h"
 #include "temp_sensor_g781.h"
+#include "util.h"
+
+static int g781_read8(const int offset, int *data_ptr)
+{
+	return i2c_read8(I2C_PORT_THERMAL, G781_I2C_ADDR, offset, data_ptr);
+}
+
+static int g781_write8(const int offset, int data)
+{
+	return i2c_write8(I2C_PORT_THERMAL, G781_I2C_ADDR, offset, data);
+}
+
+static int g781_get_temp(const int offset, int *temp_ptr)
+{
+	int rv;
+	int temp_raw = 0;
+
+	rv = g781_read8(offset, &temp_raw);
+	if (rv < 0)
+		return rv;
+
+	*temp_ptr = (int)(int8_t)temp_raw;
+	return EC_SUCCESS;
+}
+
+static int g781_set_temp(const int offset, int temp)
+{
+	if (temp < -127 || temp > 127)
+		return EC_ERROR_INVAL;
+
+	return g781_write8(offset, (uint8_t)temp);
+}
 
 int g781_get_val(int idx, int *temp_ptr)
 {
-	int command;
+	int offset;
 	int rv;
-	int temp_raw = 0;
 
 	if (!board_g781_has_power())
 		return EC_ERROR_NOT_POWERED;
 
 	switch (idx) {
 	case 0:
-		command = G781_TEMP_LOCAL;
+		offset = G781_TEMP_LOCAL;
 		break;
 	case 1:
-		command = G781_TEMP_REMOTE;
+		offset = G781_TEMP_REMOTE;
 		break;
 	default:
 		return EC_ERROR_UNKNOWN;
 	}
 
-	rv = i2c_read8(I2C_PORT_THERMAL, G781_I2C_ADDR, command, &temp_raw);
-
+	rv = g781_get_temp(offset, temp_ptr);
 	if (rv < 0)
 		return rv;
 
-	/* Negative numbers are 2's compliment with sign bit 7 */
-	if (temp_raw & (1 << 7))
-		temp_raw = ~(~temp_raw & 0xff) + 1;
-
 	/* Temperature from sensor is in degrees Celsius */
-	*temp_ptr = C_TO_K(temp_raw);
+	*temp_ptr = C_TO_K(*temp_ptr);
 	return EC_SUCCESS;
 }
+
+static int g781_show_status(void)
+{
+	int value;
+	int rv;
+
+
+	rv = g781_get_temp(G781_TEMP_LOCAL, &value);
+	if (rv < 0)
+		return rv;
+	ccprintf("Local Temp:   %3dC\n", value);
+
+	rv = g781_get_temp(G781_LOCAL_TEMP_THERM_LIMIT, &value);
+	if (rv < 0)
+		return rv;
+	ccprintf("  Therm Trip: %3dC\n", value);
+
+	rv = g781_get_temp(G781_LOCAL_TEMP_HIGH_LIMIT_R, &value);
+	if (rv < 0)
+		return rv;
+	ccprintf("  High Alarm: %3dC\n", value);
+
+	rv = g781_get_temp(G781_LOCAL_TEMP_LOW_LIMIT_R, &value);
+	if (rv < 0)
+		return rv;
+	ccprintf("  Low Alarm:  %3dC\n", value);
+
+	rv = g781_get_temp(G781_TEMP_REMOTE, &value);
+	if (rv < 0)
+		return rv;
+	ccprintf("Remote Temp:  %3dC\n", value);
+
+	rv = g781_get_temp(G781_REMOTE_TEMP_THERM_LIMIT, &value);
+	if (rv < 0)
+		return rv;
+	ccprintf("  Therm Trip: %3dC\n", value);
+
+	rv = g781_get_temp(G781_REMOTE_TEMP_HIGH_LIMIT_R, &value);
+	if (rv < 0)
+		return rv;
+	ccprintf("  High Alarm: %3dC\n", value);
+
+	rv = g781_get_temp(G781_REMOTE_TEMP_LOW_LIMIT_R, &value);
+	if (rv < 0)
+		return rv;
+	ccprintf("  Low Alarm:  %3dC\n", value);
+
+	rv = g781_read8(G781_STATUS, &value);
+	if (rv < 0)
+		return rv;
+	ccprintf("\nSTATUS: %08b\n", value);
+
+	rv = g781_read8(G781_CONFIGURATION_R, &value);
+	if (rv < 0)
+		return rv;
+	ccprintf("CONFIG: %08b\n", value);
+
+	return EC_SUCCESS;
+}
+
+static int command_g781(int argc, char **argv)
+{
+	char *command;
+	char *e;
+	int data;
+	int offset;
+	int rv;
+
+	if (!board_g781_has_power()) {
+		ccprintf("ERROR: Temp sensor not powered.\n");
+		return EC_ERROR_NOT_POWERED;
+	}
+
+	/* If no args just print status */
+	if (argc == 1)
+		return g781_show_status();
+
+	if (argc < 3)
+		return EC_ERROR_PARAM_COUNT;
+
+	command = argv[1];
+	offset = strtoi(argv[2], &e, 0);
+	if (*e || offset < 0 || offset > 255)
+		return EC_ERROR_PARAM2;
+
+	if (!strcasecmp(command, "getbyte")) {
+		rv = g781_read8(offset, &data);
+		if (rv < 0)
+			return rv;
+		ccprintf("Byte at offset 0x%02x is %08b\n", offset, data);
+		return rv;
+	}
+
+	/* Remaining commands are of the form "g781 set-command offset data" */
+	if (argc != 4)
+		return EC_ERROR_PARAM_COUNT;
+
+	data = strtoi(argv[3], &e, 0);
+	if (*e)
+		return EC_ERROR_PARAM3;
+
+	if (!strcasecmp(command, "settemp")) {
+		ccprintf("Setting 0x%02x to %dC\n", offset, data);
+		rv = g781_set_temp(offset, data);
+	} else if (!strcasecmp(command, "setbyte")) {
+		ccprintf("Setting 0x%02x to 0x%02x\n", offset, data);
+		rv = g781_write8(offset, data);
+	} else
+		return EC_ERROR_PARAM1;
+
+	return rv;
+}
+DECLARE_CONSOLE_COMMAND(g781, command_g781,
+	"[settemp|setbyte <offset> <value>] or [getbyte <offset>]. "
+	"Temps in Celsius.",
+	"Print g781 temp sensor status or set parameters.", NULL);

include/temp_sensor_g781.h

@@ -11,13 +11,52 @@
 #define G781_I2C_ADDR		0x98 /* 7-bit address is 0x4C */
 
 /* Chip-specific commands */
-#define G781_TEMP_LOCAL		0x00
-#define G781_TEMP_REMOTE	0x01
+#define G781_TEMP_LOCAL			0x00
+#define G781_TEMP_REMOTE		0x01
+#define G781_STATUS			0x02
+#define G781_CONFIGURATION_R		0x03
+#define G781_CONVERSION_RATE_R		0x04
+#define G781_LOCAL_TEMP_HIGH_LIMIT_R	0x05
+#define G781_LOCAL_TEMP_LOW_LIMIT_R	0x06
+#define G781_REMOTE_TEMP_HIGH_LIMIT_R	0x07
+#define G781_REMOTE_TEMP_LOW_LIMIT_R	0x08
+#define G781_CONFIGURATION_W		0x09
+#define G781_CONVERSION_RATE_W		0x0a
+#define G781_LOCAL_TEMP_HIGH_LIMIT_W	0x0b
+#define G781_LOCAL_TEMP_LOW_LIMIT_W	0x0c
+#define G781_REMOTE_TEMP_HIGH_LIMIT_W	0x0d
+#define G781_REMOTE_TEMP_LOW_LIMIT_W	0x0e
+#define G781_ONESHOT			0x0f
+#define G781_REMOTE_TEMP_EXTENDED	0x10
+#define G781_REMOTE_TEMP_OFFSET_HIGH	0x11
+#define G781_REMOTE_TEMP_OFFSET_EXTD	0x12
+#define G781_REMOTE_T_HIGH_LIMIT_EXTD	0x13
+#define G781_REMOTE_T_LOW_LIMIT_EXTD	0x14
+#define G781_REMOTE_TEMP_THERM_LIMIT	0x19
+#define G781_LOCAL_TEMP_THERM_LIMIT	0x20
+#define G781_THERM_HYSTERESIS		0x21
+#define G781_ALERT_FAULT_QUEUE_CODE	0x22
+#define G781_MANUFACTURER_ID		0xFE
+#define G781_DEVICE_ID			0xFF
+
+/* Config register bits */
+#define G781_CONFIGURATION_STANDBY	(1 << 6)
+#define G781_CONFIGURATION_ALERT_MASK	(1 << 7)
+
+/* Status register bits */
+#define G781_STATUS_LOCAL_TEMP_THERM_ALARM	(1 << 0)
+#define G781_STATUS_REMOTE_TEMP_THERM_ALARM	(1 << 1)
+#define G781_STATUS_REMOTE_TEMP_FAULT		(1 << 2)
+#define G781_STATUS_REMOTE_TEMP_LOW_ALARM	(1 << 3)
+#define G781_STATUS_REMOTE_TEMP_HIGH_ALARM	(1 << 4)
+#define G781_STATUS_LOCAL_TEMP_LOW_ALARM	(1 << 5)
+#define G781_STATUS_LOCAL_TEMP_HIGH_ALARM	(1 << 6)
+#define G781_STATUS_BUSY			(1 << 7)
 
 /**
  * Get the last polled value of a sensor.
  *
- * @param idx		Index to read.  Idx indicates whether to read die
+ * @param idx		Index to read. Idx indicates whether to read die
  *			temperature or external temperature.
  * @param temp_ptr	Destination for temperature in K.
  *