pinctrl: intel: Protect IO in few call backs by lock

Protect IO in intel_gpio_get_direction(), intel_gpio_community_irq_handler(),
intel_config_get_debounce() and intel_config_get_pull() by lock. Even for
simple readl() we better serialize IO to avoid potential problems.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>

drivers/pinctrl/intel/pinctrl-intel.c

@@ -526,11 +526,15 @@ static int intel_config_get_pull(struct intel_pinctrl *pctrl, unsigned int pin,
 {
 	const struct intel_community *community;
 	void __iomem *padcfg1;
+	unsigned long flags;
 	u32 value, term;
 
 	community = intel_get_community(pctrl, pin);
 	padcfg1 = intel_get_padcfg(pctrl, pin, PADCFG1);
+
+	raw_spin_lock_irqsave(&pctrl->lock, flags);
 	value = readl(padcfg1);
+	raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 
 	term = (value & PADCFG1_TERM_MASK) >> PADCFG1_TERM_SHIFT;
 
@@ -592,6 +596,7 @@ static int intel_config_get_debounce(struct intel_pinctrl *pctrl, unsigned int p
 				     enum pin_config_param param, u32 *arg)
 {
 	void __iomem *padcfg2;
+	unsigned long flags;
 	unsigned long v;
 	u32 value2;
 
@@ -599,7 +604,9 @@ static int intel_config_get_debounce(struct intel_pinctrl *pctrl, unsigned int p
 	if (!padcfg2)
 		return -ENOTSUPP;
 
+	raw_spin_lock_irqsave(&pctrl->lock, flags);
 	value2 = readl(padcfg2);
+	raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 	if (!(value2 & PADCFG2_DEBEN))
 		return -EINVAL;
 
@@ -934,6 +941,7 @@ static void intel_gpio_set(struct gpio_chip *chip, unsigned int offset,
 static int intel_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
 {
 	struct intel_pinctrl *pctrl = gpiochip_get_data(chip);
+	unsigned long flags;
 	void __iomem *reg;
 	u32 padcfg0;
 	int pin;
@@ -946,8 +954,9 @@ static int intel_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
 	if (!reg)
 		return -EINVAL;
 
+	raw_spin_lock_irqsave(&pctrl->lock, flags);
 	padcfg0 = readl(reg);
-
+	raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 	if (padcfg0 & PADCFG0_PMODE_MASK)
 		return -EINVAL;
 
@@ -1134,12 +1143,17 @@ static int intel_gpio_community_irq_handler(struct intel_pinctrl *pctrl,
 	for (gpp = 0; gpp < community->ngpps; gpp++) {
 		const struct intel_padgroup *padgrp = &community->gpps[gpp];
 		unsigned long pending, enabled, gpp_offset;
+		unsigned long flags;
+
+		raw_spin_lock_irqsave(&pctrl->lock, flags);
 
 		pending = readl(community->regs + community->is_offset +
 				padgrp->reg_num * 4);
 		enabled = readl(community->regs + community->ie_offset +
 				padgrp->reg_num * 4);
 
+		raw_spin_unlock_irqrestore(&pctrl->lock, flags);
+
 		/* Only interrupts that are enabled */
 		pending &= enabled;