[imx9 boot reason 1/4] imx9_pmic driver

arch/arm64/src/imx9/imx9_pmic.c

@@ -48,6 +48,7 @@
 #define PCA9451A_I2C_ADDR       0x25
 #define REG_SW_RST              0x06
 #define REG_POWERON_STAT        0x05
+#define REG_RESET_CTRL          0x08
 #define COLD_RESET              0x64
 #define WARM_RESET              0x35
 
@@ -56,57 +57,69 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: imx9_pmic_reset
+ * Name: imx9_pmic_reg_read
  *
  * Description:
- *   Reset SoC via pmic
+ *   Read 8-bit register value from pmic
  *
  ****************************************************************************/
 
-void imx9_pmic_reset(void)
+static int imx9_pmic_reg_read(uint8_t reg, uint8_t *value)
 {
   struct i2c_master_s *i2c;
-  struct i2c_msg_s msg;
-  uint8_t buffer[2];
+  struct i2c_msg_s msgs[2];
+  uint8_t reg_addr = reg;
   int ret;
 
-  i2c = imx9_i2cbus_initialize(CONFIG_IMX9_PMIC_I2C);
+  if (!value)
+    {
+      _err("Invalid value parameter\n");
+      return -EINVAL;
+    }
 
+  i2c = imx9_i2cbus_initialize(CONFIG_IMX9_PMIC_I2C);
   if (i2c == NULL)
     {
-      return;
+      _err("Failed to initialize I2C bus\n");
+      return -ENODEV;
     }
 
-  buffer[0] = REG_SW_RST;
-  buffer[1] = COLD_RESET;
+  msgs[0].frequency = 400000;
+  msgs[0].addr      = PCA9451A_I2C_ADDR;
+  msgs[0].flags     = 0;
+  msgs[0].buffer    = &reg_addr;
+  msgs[0].length    = 1;
 
-  msg.frequency = 400000;
-  msg.addr      = PCA9451A_I2C_ADDR;
-  msg.flags     = 0;
-  msg.buffer    = buffer;
-  msg.length    = 2;
+  msgs[1].frequency = 400000;
+  msgs[1].addr      = PCA9451A_I2C_ADDR;
+  msgs[1].flags     = I2C_M_READ;
+  msgs[1].buffer    = value;
+  msgs[1].length    = 1;
 
-  ret = I2C_TRANSFER(i2c, &msg, 1);
+  ret = I2C_TRANSFER(i2c, msgs, 2);
   if (ret < 0)
     {
-      _err("ERROR: Failed to write reset via I2C2 interface\n");
+      _err("I2C transfer failed: %d\n", ret);
     }
+
+  imx9_i2cbus_uninitialize(i2c);
+
+  return ret < 0 ? ret : 0; /* negative errno or 0 */
 }
 
 /****************************************************************************
- * Name: imx9_get_pmic_reset_reason
+ * Name: imx9_pmic_reg_read
  *
  * Description:
- *   Read reset reason from pmic
+ *   Write 8-bit register value to pmic
  *
  ****************************************************************************/
 
-uint32_t imx9_pmic_getreset_reason(void)
+static int imx9_pmic_reg_write(uint8_t reg, uint8_t val)
 {
   struct i2c_master_s *i2c;
-  struct i2c_msg_s msgs[2];
-  uint8_t reg_addr = REG_POWERON_STAT;
-  uint8_t data;
+  struct i2c_msg_s msg;
+  uint8_t buffer[2];
   int ret;
 
   i2c = imx9_i2cbus_initialize(CONFIG_IMX9_PMIC_I2C);
@@ -116,26 +129,80 @@ uint32_t imx9_pmic_getreset_reason(void)
       return -ENODEV;
     }
 
-  msgs[0].frequency = 400000;
-  msgs[0].addr      = PCA9451A_I2C_ADDR;
-  msgs[0].flags     = 0;
-  msgs[0].buffer    = &reg_addr;
-  msgs[0].length    = 1;
+  buffer[0] = reg;
+  buffer[1] = val;
 
-  msgs[1].frequency = 400000;
-  msgs[1].addr      = PCA9451A_I2C_ADDR;
-  msgs[1].flags     = I2C_M_READ;
-  msgs[1].buffer    = &data;
-  msgs[1].length    = 1;
+  msg.frequency = 400000;
+  msg.addr      = PCA9451A_I2C_ADDR;
+  msg.flags     = 0;
+  msg.buffer    = buffer;
+  msg.length    = 2;
 
-  ret = I2C_TRANSFER(i2c, msgs, 2);
+  ret = I2C_TRANSFER(i2c, &msg, 1);
   if (ret < 0)
     {
       _err("I2C transfer failed: %d\n", ret);
-      imx9_i2cbus_uninitialize(i2c);
-      return ret;
     }
 
   imx9_i2cbus_uninitialize(i2c);
-  return (uint32_t)data;
+
+  return ret < 0 ? ret : 0; /* negative errno or 0 */
+}
+
+/****************************************************************************
+ * Name: imx9_pmic_reset
+ *
+ * Description:
+ *   Reset SoC via pmic
+ *
+ ****************************************************************************/
+
+int imx9_pmic_reset(void)
+{
+  return imx9_pmic_reg_write(REG_SW_RST, COLD_RESET);
+}
+
+/****************************************************************************
+ * Name: imx9_pmic_get_reset_reason
+ *
+ * Description:
+ *   Read reset reason from pmic
+ *
+ ****************************************************************************/
+
+int imx9_pmic_get_reset_reason(uint8_t *value)
+{
+  return imx9_pmic_reg_read(REG_POWERON_STAT, value);
+}
+
+/****************************************************************************
+ * Name: imx9_pmic_get_reset_ctrl
+ *
+ * Description:
+ *  Read reset control register value
+ *
+ ****************************************************************************/
+
+int imx9_pmic_get_reset_ctrl(uint8_t *value)
+{
+  return imx9_pmic_reg_read(REG_RESET_CTRL, value);
+}
+
+/****************************************************************************
+ * Name: imx9_pmic_set_reset_ctrl
+ *
+ * Description:
+ *  Set reset control register value
+ *
+ * Input Parameters:
+ *   Register value
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+int imx9_pmic_set_reset_ctrl(uint8_t val)
+{
+  return imx9_pmic_reg_write(REG_RESET_CTRL, val);
 }

arch/arm64/src/imx9/imx9_pmic.h

@@ -44,21 +44,27 @@ extern "C"
 #define EXTERN extern
 #endif
 
+#define IMX9_PMIC_RESET_CTRL_DEFAULT                0x21
+
+/* WDOG_B_CFG [7:6]: 11b (Cold Reset) */
+
+#define IMX9_PMIC_RESET_CTRL_WDOG_COLD_RESET_MASK   0xC0
+
 /****************************************************************************
- * Name: imx9_pmic_getreset_reason
+ * Name: imx9_pmic_get_reset_reason
  *
  * Description:
  *  Read reset reason from pmic via i2c
  *
  * Input Parameters:
- *   None
+ *   Pointer to reset reason value
  *
  * Returned Value:
- *   uin32_t, reset reason
+ *   Zero on success or error code
  *
  ****************************************************************************/
 
-uint32_t imx9_pmic_getreset_reason(void);
+int imx9_pmic_get_reset_reason(uint8_t *value);
 
 /****************************************************************************
  * Name: imx9_pmic_reset
@@ -70,11 +76,43 @@ uint32_t imx9_pmic_getreset_reason(void);
  *   None
  *
  * Returned Value:
- *   None
+ *   Zero on success or error code
+ *
+ ****************************************************************************/
+
+int imx9_pmic_reset(void);
+
+/****************************************************************************
+ * Name: imx9_pmic_get_reset_ctrl
+ *
+ * Description:
+ *  Read reset control register value
+ *
+ * Input Parameters:
+ *   Pointer to reset reason value
+ *
+ * Returned Value:
+ *   Zero on success or error code
+ *
+ ****************************************************************************/
+
+int imx9_pmic_get_reset_ctrl(uint8_t *value);
+
+/****************************************************************************
+ * Name: imx9_pmic_set_reset_ctrl
+ *
+ * Description:
+ *  Set reset control register value
+ *
+ * Input Parameters:
+ *   Register value
+ *
+ * Returned Value:
+ *   Zero on success or error code
  *
  ****************************************************************************/
 
-void imx9_pmic_reset(void);
+int imx9_pmic_set_reset_ctrl(uint8_t val);
 
 #undef EXTERN
 #if defined(__cplusplus)