staging: hikey9xx: hi6421v600-regulator: get rid of an static data

Move it to be inside the private data struct.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/ff8b6852c788fd476743eb4ce556e4a97f4b928e.1611212783.git.mchehab+huawei@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/hikey9xx/hi6421v600-regulator.c

@@ -28,9 +28,10 @@ struct hi6421_spmi_reg_info {
 	struct hi6421_spmi_pmic *pmic;
 	u8			eco_mode_mask;
 	u32			eco_uA;
-};
 
-static DEFINE_MUTEX(enable_mutex);
+	/* Serialize regulator enable logic */
+	struct mutex enable_mutex;
+};
 
 static const unsigned int ldo3_voltages[] = {
 	1500000, 1550000, 1600000, 1650000,
@@ -118,7 +119,7 @@ static int hi6421_spmi_regulator_enable(struct regulator_dev *rdev)
 	struct hi6421_spmi_pmic *pmic = sreg->pmic;
 
 	/* cannot enable more than one regulator at one time */
-	mutex_lock(&enable_mutex);
+	mutex_lock(&sreg->enable_mutex);
 	usleep_range(HISI_REGS_ENA_PROTECT_TIME,
 		     HISI_REGS_ENA_PROTECT_TIME + 1000);
 
@@ -127,7 +128,7 @@ static int hi6421_spmi_regulator_enable(struct regulator_dev *rdev)
 			     rdev->desc->enable_mask,
 			     rdev->desc->enable_mask);
 
-	mutex_unlock(&enable_mutex);
+	mutex_unlock(&sreg->enable_mutex);
 
 	return 0;
 }
@@ -312,6 +313,7 @@ static int hi6421_spmi_regulator_probe(struct platform_device *pdev)
 		return -ENOMEM;
 
 	sreg->pmic = pmic;
+	mutex_init(&sreg->enable_mutex);
 
 	for (i = 0; i < ARRAY_SIZE(regulator_info); i++) {
 		/* assign per-regulator data */