Add STLM75 temperatire sensor driver library

CL: Add STLM75 temperature sensor driver library

PUBLISHED_FROM=fa85465f4db0e970f5ac371a1eaae9b69ec072cd

LICENSE

@@ -0,0 +1,14 @@
+Copyright (c) 2019 Cesanta Software Limited
+All rights reserved
+
+Licensed under the Apache License, Version 2.0 (the ""License"");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an ""AS IS"" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.

include/mgos_stlm75.h

@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2014-2019 Cesanta Software Limited
+ * All rights reserved
+ *
+ * Licensed under the Apache License, Version 2.0 (the ""License"");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an ""AS IS"" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "mgos_i2c.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Lower 3 bits are determined by A2,A1,A0 pins, hence 0x48-0x4f are possible.
+#define MGOS_STLM75_ADDR_000 0x48
+#define MGOS_STLM75_ADDR_001 0x49
+#define MGOS_STLM75_ADDR_010 0x4a
+#define MGOS_STLM75_ADDR_011 0x4b
+#define MGOS_STLM75_ADDR_100 0x4c
+#define MGOS_STLM75_ADDR_101 0x4d
+#define MGOS_STLM75_ADDR_110 0x4e
+#define MGOS_STLM75_ADDR_111 0x4f
+
+struct mgos_stlm75 {
+  struct mgos_i2c *i2c;
+  uint16_t addr;
+};
+
+struct mgos_stlm75 *mgos_stlm75_create(struct mgos_i2c *i2c, uint16_t addr);
+
+void mgos_stlm75_init(struct mgos_stlm75 *ctx, struct mgos_i2c *i2c,
+                      uint16_t addr);
+
+bool mgos_stlm75_read_temp(struct mgos_stlm75 *ctx, float *temp);
+
+// Interrup vs comparator mode. See datasheet for detailed explanation.
+enum mgos_stlm75_int_mode {
+  MGOS_STLM75_INT_MODE_COMP = 0,
+  MGOS_STLM75_INT_MODE_INT = 1,
+};
+
+// Interrupt active polarity.
+enum mgos_stlm75_int_pol {
+  MGOS_STLM75_INT_POL_NEG = 0,
+  MGOS_STLM75_INT_POL_POS = 1,
+};
+
+// "Fault tolerance" - the temperature value must exceed threshold
+// for 1, 2, 4 or 6 cycles before interrupt is asserted.
+enum mgos_stlm75_int_ft {
+  MGOS_STLM75_INT_FT_1 = 0,
+  MGOS_STLM75_INT_FT_2 = 1,
+  MGOS_STLM75_INT_FT_4 = 2,
+  MGOS_STLM75_INT_FT_6 = 3,
+};
+
+bool mgos_stlm75_set_alarm(struct mgos_stlm75 *ctx, float hi, float lo,
+                           enum mgos_stlm75_int_mode mode,
+                           enum mgos_stlm75_int_pol pol,
+                           enum mgos_stlm75_int_ft ft);
+
+// Put the device in or out of shutdown.
+bool mgos_stlm75_shutdown(struct mgos_stlm75 *ctx, bool shutdown);
+
+void mgos_stlm75_free(struct mgos_stlm75 *ctx);
+
+#ifdef __cplusplus
+}
+#endif

mos.yml

@@ -0,0 +1,16 @@
+author: mongoose-os
+type: lib
+description: STMicro STLM75 temperature sensor driver
+version: 1.0
+sources:
+  - src
+includes:
+  - include
+libs:
+  - origin: https://github.com/mongoose-os-libs/i2c
+tags:
+  - c
+  - hw
+  - docs:drivers:STLM75
+
+manifest_version: 2017-09-29

src/mgos_stlm75.c

@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2014-2019 Cesanta Software Limited
+ * All rights reserved
+ *
+ * Licensed under the Apache License, Version 2.0 (the ""License"");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an ""AS IS"" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "mgos_stlm75.h"
+
+#include <stdlib.h>
+
+#include "common/cs_dbg.h"
+
+#define MGOS_STLM75_REG_TEMP 0
+#define MGOS_STLM75_REG_CONF 1
+#define MGOS_STLM75_REG_TOS 2
+#define MGOS_STLM75_REG_THYS 3
+
+static float reg_val_to_temp(uint16_t val) {
+  int16_t val16 = ((int16_t) val) >> 7;
+  return ((float) val16) * 0.5f;
+}
+
+static uint16_t temp_to_reg_val(float temp) {
+  int16_t val16 = (int16_t)(temp / 0.5f);
+  return ((uint16_t)(val16 << 7));
+}
+
+struct mgos_stlm75 *mgos_stlm75_create(struct mgos_i2c *i2c, uint16_t addr) {
+  if (i2c == NULL) return NULL;
+  struct mgos_stlm75 *ctx = (struct mgos_stlm75 *) calloc(1, sizeof(*ctx));
+  if (ctx != NULL) mgos_stlm75_init(ctx, i2c, addr);
+  return ctx;
+}
+
+void mgos_stlm75_init(struct mgos_stlm75 *ctx, struct mgos_i2c *i2c,
+                      uint16_t addr) {
+  ctx->i2c = i2c;
+  ctx->addr = addr;
+}
+
+bool mgos_stlm75_read_temp(struct mgos_stlm75 *ctx, float *temp) {
+  int val = mgos_i2c_read_reg_w(ctx->i2c, ctx->addr, MGOS_STLM75_REG_TEMP);
+  if (val < 0) {
+    *temp = 0;
+    return false;
+  }
+  *temp = reg_val_to_temp(val);
+  return true;
+}
+
+bool mgos_stlm75_set_alarm(struct mgos_stlm75 *ctx, float hi, float lo,
+                           enum mgos_stlm75_int_mode mode,
+                           enum mgos_stlm75_int_pol pol,
+                           enum mgos_stlm75_int_ft ft) {
+  uint8_t cfg = ((((uint8_t) ft) << 3) | (((uint8_t) pol) << 2) |
+                 (((uint8_t) mode) << 1));
+  if (!mgos_i2c_write_reg_w(ctx->i2c, ctx->addr, MGOS_STLM75_REG_TOS,
+                            temp_to_reg_val(hi)) ||
+      !mgos_i2c_write_reg_w(ctx->i2c, ctx->addr, MGOS_STLM75_REG_THYS,
+                            temp_to_reg_val(lo)) ||
+      !mgos_i2c_setbits_reg_b(ctx->i2c, ctx->addr, MGOS_STLM75_REG_CONF, 1, 4,
+                              (cfg >> 1))) {
+    return false;
+  }
+  LOG(LL_INFO,
+      ("Set %04x %04x %02x",
+       mgos_i2c_read_reg_w(ctx->i2c, ctx->addr, MGOS_STLM75_REG_TOS),
+       mgos_i2c_read_reg_w(ctx->i2c, ctx->addr, MGOS_STLM75_REG_THYS),
+       mgos_i2c_read_reg_b(ctx->i2c, ctx->addr, MGOS_STLM75_REG_CONF)));
+  return true;
+}
+
+bool mgos_stlm75_shutdown(struct mgos_stlm75 *ctx, bool shutdown) {
+  return mgos_i2c_setbits_reg_b(ctx->i2c, ctx->addr, MGOS_STLM75_REG_CONF, 0, 1,
+                                (uint8_t) shutdown);
+}
+
+void mgos_stlm75_free(struct mgos_stlm75 *ctx) {
+  free(ctx);
+}