[PATCH 4/4] pinctrl: rockchip: Protect read-modify-write with the spinlock

From: Doug Anderson
Date: Mon Oct 20 2014 - 19:28:31 EST


There were a few instances where the rockchip pinctrl driver would do
read-modify-write with no spinlock. Add a spinlock for these cases.

Signed-off-by: Doug Anderson <dianders@xxxxxxxxxxxx>
---
drivers/pinctrl/pinctrl-rockchip.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)

diff --git a/drivers/pinctrl/pinctrl-rockchip.c b/drivers/pinctrl/pinctrl-rockchip.c
index 14a5683..669e5e8 100644
--- a/drivers/pinctrl/pinctrl-rockchip.c
+++ b/drivers/pinctrl/pinctrl-rockchip.c
@@ -871,6 +871,8 @@ static int _rockchip_pmx_gpio_set_direction(struct gpio_chip *gc,
if (ret < 0)
return ret;

+ spin_lock_irqsave(&bank->slock, flags);
+
data = readl_relaxed(bank->reg_base + GPIO_SWPORT_DDR);
/* set bit to 1 for output, 0 for input */
if (!input)
@@ -879,6 +881,8 @@ static int _rockchip_pmx_gpio_set_direction(struct gpio_chip *gc,
data &= ~BIT(pin);
writel_relaxed(data, bank->reg_base + GPIO_SWPORT_DDR);

+ spin_unlock_irqrestore(&bank->slock, flags);
+
return 0;
}

@@ -1395,6 +1399,7 @@ static void rockchip_irq_demux(unsigned int irq, struct irq_desc *desc)
u32 polarity = 0, data = 0;
u32 pend;
bool edge_changed = false;
+ unsigned long flags;

dev_dbg(bank->drvdata->dev, "got irq for bank %s\n", bank->name);

@@ -1440,10 +1445,14 @@ static void rockchip_irq_demux(unsigned int irq, struct irq_desc *desc)

if (bank->toggle_edge_mode && edge_changed) {
/* Interrupt params should only be set with ints disabled */
+ spin_lock_irqsave(&bank->slock, flags);
+
data = readl_relaxed(bank->reg_base + GPIO_INTEN);
writel_relaxed(0, bank->reg_base + GPIO_INTEN);
writel(polarity, bank->reg_base + GPIO_INT_POLARITY);
writel(data, bank->reg_base + GPIO_INTEN);
+
+ spin_unlock_irqrestore(&bank->slock, flags);
}

chained_irq_exit(chip, desc);
@@ -1457,6 +1466,7 @@ static int rockchip_irq_set_type(struct irq_data *d, unsigned int type)
u32 polarity;
u32 level;
u32 data;
+ unsigned long flags;
int ret;

/* make sure the pin is configured as gpio input */
@@ -1464,15 +1474,20 @@ static int rockchip_irq_set_type(struct irq_data *d, unsigned int type)
if (ret < 0)
return ret;

+ spin_lock_irqsave(&bank->slock, flags);
+
data = readl_relaxed(bank->reg_base + GPIO_SWPORT_DDR);
data &= ~mask;
writel_relaxed(data, bank->reg_base + GPIO_SWPORT_DDR);

+ spin_unlock_irqrestore(&bank->slock, flags);
+
if (type & IRQ_TYPE_EDGE_BOTH)
__irq_set_handler_locked(d->irq, handle_edge_irq);
else
__irq_set_handler_locked(d->irq, handle_level_irq);

+ spin_lock_irqsave(&bank->slock, flags);
irq_gc_lock(gc);

level = readl_relaxed(gc->reg_base + GPIO_INTTYPE_LEVEL);
@@ -1522,6 +1537,7 @@ static int rockchip_irq_set_type(struct irq_data *d, unsigned int type)
writel_relaxed(polarity, gc->reg_base + GPIO_INT_POLARITY);

irq_gc_unlock(gc);
+ spin_unlock_irqrestore(&bank->slock, flags);

return 0;
}
--
2.1.0.rc2.206.gedb03e5

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