misc: eeprom: at24: check suspend status before disable regulator

cd5676db05 ("misc: eeprom: at24: support pm_runtime control") disables
regulator in runtime suspend. If runtime suspend is called before
regulator disable, it will results in regulator unbalanced disabling.

Fixes: cd5676db05 ("misc: eeprom: at24: support pm_runtime control")
Cc: stable <stable@vger.kernel.org>
Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Link: https://lore.kernel.org/r/20210420133050.377209-1-hsinyi@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/eeprom/at24.c

@@ -763,7 +763,8 @@ static int at24_probe(struct i2c_client *client)
 	at24->nvmem = devm_nvmem_register(dev, &nvmem_config);
 	if (IS_ERR(at24->nvmem)) {
 		pm_runtime_disable(dev);
-		regulator_disable(at24->vcc_reg);
+		if (!pm_runtime_status_suspended(dev))
+			regulator_disable(at24->vcc_reg);
 		return PTR_ERR(at24->nvmem);
 	}
 
@@ -774,7 +775,8 @@ static int at24_probe(struct i2c_client *client)
 	err = at24_read(at24, 0, &test_byte, 1);
 	if (err) {
 		pm_runtime_disable(dev);
-		regulator_disable(at24->vcc_reg);
+		if (!pm_runtime_status_suspended(dev))
+			regulator_disable(at24->vcc_reg);
 		return -ENODEV;
 	}