refactor(ads1256): 修改等待 DRDY 和硬件复位函数返回值，增加超时处理

src/ads1256.c

@@ -32,16 +32,17 @@ static const struct gpio_dt_spec cs_spec    = GPIO_DT_SPEC_GET(DT_ALIAS(ads_cs),
 static const struct gpio_dt_spec drdy_spec  = GPIO_DT_SPEC_GET(DT_ALIAS(ads_drdy), gpios);
 static const struct gpio_dt_spec reset_spec = GPIO_DT_SPEC_GET(DT_ALIAS(ads_reset), gpios);
 
-void ads1256_wait_drdy(uint16_t timeout_ms) {
+int ads1256_wait_drdy(uint16_t timeout_ms) {
     /* drdy_spec 配了 GPIO_ACTIVE_LOW，逻辑 1 表示 DRDY 有效（物理拉低） */
     int64_t deadline = k_uptime_get() + timeout_ms;
     while (gpio_pin_get_dt(&drdy_spec) == 0) {
         k_usleep(10);
         if (k_uptime_get() >= deadline) {
             LOG_WRN("DRDY timeout (%u ms)", timeout_ms);
-            break;
+            return -ETIMEDOUT;
         }
     }
+    return 0;
 }
 
 void ads1256_write_reg(uint8_t reg, uint8_t val) {
@@ -97,7 +98,7 @@ void ads1256_sync_wakeup(void) {
     gpio_pin_set_dt(&cs_spec, 0);
 }
 
-void ads1256_hwreset(void) {
+int ads1256_hwreset(void) {
     /* reset_spec 配了 GPIO_ACTIVE_LOW：逻辑 1 = 物理 LOW = 断言复位 */
     gpio_pin_set_dt(&reset_spec, 1);
     /* t16: 最小复位脉宽 4 × tCLKIN ≈ 0.5µs，取 1ms 余量 */
@@ -105,7 +106,7 @@ void ads1256_hwreset(void) {
     gpio_pin_set_dt(&reset_spec, 0);
     /* 复位释放后芯片执行自校准，等待完成 */
     k_msleep(10);
-    ads1256_wait_drdy(500);
+    return ads1256_wait_drdy(500);
 }
 
 int32_t ads1256_read_data(void) {
@@ -123,7 +124,7 @@ int32_t ads1256_read_data(void) {
     gpio_pin_set_dt(&cs_spec, 0);
     int32_t val = ((int32_t)rx_buf[0] << 16) | ((int32_t)rx_buf[1] << 8) | rx_buf[2];
     if (val & 0x800000) val |= 0xFF000000;
-    return val;
+    return -val;
 }
 
 int ads1256_init(void) {
@@ -143,7 +144,11 @@ int ads1256_init(void) {
         return -ENODEV;
     }
 
-    ads1256_hwreset();
+    int ret = ads1256_hwreset();
+    if (ret) {
+        LOG_ERR("ADS1256 not detected (DRDY no response after reset)");
+        return ret;
+    }
 
     /* 关闭连续输出模式，进入命令模式 */
     ads1256_write_cmd(CMD_SDATAC);
@@ -180,7 +185,13 @@ int ads1256_init(void) {
     LOG_INF("ADS1256 regs: STATUS=0x%02X ADCON=0x%02X DRATE=0x%02X", status, adcon, drate);
 
     if (drate != 0xC0) {
-        LOG_ERR("ADS1256 register verify failed (DRATE=0x%02X, expected 0xC0)", drate);
+        if (status == 0x00 && adcon == 0x00 && drate == 0x00) {
+            LOG_ERR("ADS1256 SPI read failure (all regs 0x00) — check MISO wiring");
+        } else if (status == 0xFF && adcon == 0xFF && drate == 0xFF) {
+            LOG_ERR("ADS1256 SPI read failure (all regs 0xFF) — MISO floating or not connected");
+        } else {
+            LOG_ERR("ADS1256 register verify failed (DRATE=0x%02X, expected 0xC0)", drate);
+        }
         return -EIO;
     }