Disable BOB EXT CTRL1 boost prior to MCU boot

Use SPMI to disable BOB EXT_CTRL1 boost on MCU boot.

Bug: 262723868
Test: Manual, verify BOB voltage gets reset to ~3.5-3.8V if MCU
      crashes with AFE LED in high current state.
Change-Id: I545e1c89ab265d9f8629680092dc8f75f05baffb

2 files changed, 14 insertions, 0 deletions

diff --git a/main.c b/main.c
index 43ba7d5..ce658ad 100644
--- a/main.c
+++ b/main.c
@@ -829,6 +829,11 @@ static void __nanohub_hw_reset(struct nanohub_data *data, int boot_mode)
 	if (ret != 0)
 		pr_warn("nanohub: failed to disable afe_tx_sup ret=%x\n", ret);
 
+	// Disable BOB EXT CTRL1 prior to MCU boot
+	ret = regmap_write(pdata->pmic_regmap, pdata->bob_ext_ctrl1_control_reg, 0);
+	if (ret != 0)
+		pr_warn("nanohub: failed to disable bob ext ctrl1 ret=%x\n", ret);
+
 	// Disable 32KHz clock prior to MCU boot
 	ret = regmap_write(pdata->pmic_regmap, pdata->clk32_control_reg, 0);
 	if (ret != 0)
@@ -1918,6 +1923,14 @@ static struct nanohub_platform_data *nanohub_parse_dt(struct device *dev)
 		goto free_pdata;
 	}
 
+	/* required bob ext ctrl1 control register */
+	ret = of_property_read_u32(dt, "sensorhub,bob_ext_ctrl1_control",
+				   &pdata->bob_ext_ctrl1_control_reg);
+	if (ret < 0) {
+		pr_err("nanohub: missing sensorhub,bob_ext_ctrl1_control in device tree\n");
+		goto free_pdata;
+	}
+
 #ifdef CONFIG_NANOHUB_BL_ST
 	/* optional (bl-max-frequency) */
 	pdata->bl_max_speed_hz = BL_MAX_SPEED_HZ;
diff --git a/nanohub.h b/nanohub.h
index 97d8789..35a35d0 100644
--- a/nanohub.h
+++ b/nanohub.h
@@ -19,6 +19,7 @@ struct nanohub_platform_data {
 	u32 vddcore_control_reg;
 	u32 vddcore_voltage;
 	u32 clk32_control_reg;
+	u32 bob_ext_ctrl1_control_reg;
 #ifdef CONFIG_NANOHUB_BL_ST
 	u32 bl_max_speed_hz;
 	u32 bl_addr;