[PATCH v1 5/6] TODO: gpio: mlxbf2: Introduce IRQ support

From: Andy Shevchenko
Date: Mon Aug 16 2021 - 08:01:35 EST


TBD

Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
drivers/gpio/gpio-mlxbf2.c | 106 +++++++++++++++++++++++++++++++++++++
1 file changed, 106 insertions(+)

diff --git a/drivers/gpio/gpio-mlxbf2.c b/drivers/gpio/gpio-mlxbf2.c
index 3ed95e958c17..bd4c29120b62 100644
--- a/drivers/gpio/gpio-mlxbf2.c
+++ b/drivers/gpio/gpio-mlxbf2.c
@@ -43,9 +43,13 @@
#define YU_GPIO_MODE0 0x0c
#define YU_GPIO_DATASET 0x14
#define YU_GPIO_DATACLEAR 0x18
+#define YU_GPIO_CAUSE_FALL_EN 0x48
#define YU_GPIO_MODE1_CLEAR 0x50
#define YU_GPIO_MODE0_SET 0x54
#define YU_GPIO_MODE0_CLEAR 0x58
+#define YU_GPIO_CAUSE_OR_CAUSE_EVTEN0 0x80
+#define YU_GPIO_CAUSE_OR_EVTEN0 0x94
+#define YU_GPIO_CAUSE_OR_CLRCAUSE 0x98

struct mlxbf2_gpio_context_save_regs {
u32 gpio_mode0;
@@ -218,6 +222,108 @@ static int mlxbf2_gpio_direction_output(struct gpio_chip *chip,
return ret;
}

+static void mlxbf2_gpio_irq_enable(struct mlxbf2_gpio_context *gs, int offset)
+{
+ unsigned long flags;
+ u32 val;
+
+ spin_lock_irqsave(&gs->gc.bgpio_lock, flags);
+ val = readl(gs->gpio_io + YU_GPIO_CAUSE_OR_CLRCAUSE);
+ val |= BIT(offset);
+ writel(val, gs->gpio_io + YU_GPIO_CAUSE_OR_CLRCAUSE);
+
+ /* The INT_N interrupt level is active low.
+ * So enable cause fall bit to detect when GPIO
+ * state goes low.
+ */
+ val = readl(gs->gpio_io + YU_GPIO_CAUSE_FALL_EN);
+ val |= BIT(offset);
+ writel(val, gs->gpio_io + YU_GPIO_CAUSE_FALL_EN);
+
+ /* Enable PHY interrupt by setting the priority level */
+ val = readl(gs->gpio_io + YU_GPIO_CAUSE_OR_EVTEN0);
+ val |= BIT(offset);
+ writel(val, gs->gpio_io + YU_GPIO_CAUSE_OR_EVTEN0);
+ spin_unlock_irqrestore(&gs->gc.bgpio_lock, flags);
+}
+
+static void mlxbf2_gpio_irq_disable(struct mlxbf2_gpio_context *gs, int offset)
+{
+ unsigned long flags;
+ u32 val;
+
+ spin_lock_irqsave(&gs->gc.bgpio_lock, flags);
+ val = readl(gs->gpio_io + YU_GPIO_CAUSE_OR_EVTEN0);
+ val &= ~BIT(offset);
+ writel(val, gs->gpio_io + YU_GPIO_CAUSE_OR_EVTEN0);
+ spin_unlock_irqrestore(&gs->gc.bgpio_lock, flags);
+}
+
+static void mlxbf2_gpio_irq_ack(struct mlxbf2_gpio_context *gs, int offset)
+{
+ unsigned long flags;
+ u32 val;
+
+ spin_lock_irqsave(&gs->gc.bgpio_lock, flags);
+ val = readl(gs->gpio_io + YU_GPIO_CAUSE_OR_CLRCAUSE);
+ val |= BIT(offset);
+ writel(val, gs->gpio_io + YU_GPIO_CAUSE_OR_CLRCAUSE);
+ spin_unlock_irqrestore(&gs->gc.bgpio_lock, flags);
+}
+
+static irqreturn_t mlxbf2_gpio_irq_handler(int irq, void *ptr)
+{
+ struct mlxbf2_gpio_context *gs = ptr;
+ struct gpio_chip *gc = &gs->gc;
+ unsigned long pending;
+ u32 level;
+
+ pending = readl(gs->gpio_io + YU_GPIO_CAUSE_OR_CAUSE_EVTEN0);
+ for_each_set_bit(level, &pending, gc->ngpio) {
+ int nested_irq = irq_find_mapping(gc->irq.domain, level);
+
+ handle_nested_irq(nested_irq);
+ }
+
+ return IRQ_RETVAL(pending);
+}
+
+static void mlxbf2_gpio_irq_mask(struct irq_data *irqd)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd);
+ struct mlxbf2_gpio_context *gs = gpiochip_get_data(gc);
+ int offset = irqd_to_hwirq(irqd) % MLXBF2_GPIO_MAX_PINS_PER_BLOCK;
+
+ mlxbf2_gpio_irq_disable(gs, offset);
+}
+
+static void mlxbf2_gpio_irq_unmask(struct irq_data *irqd)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(irqd);
+ struct mlxbf2_gpio_context *gs = gpiochip_get_data(gc);
+ int offset = irqd_to_hwirq(irqd) % MLXBF2_GPIO_MAX_PINS_PER_BLOCK;
+
+ mlxbf2_gpio_irq_enable(gs, offset);
+}
+
+static void mlxbf2_gpio_irq_bus_lock(struct irq_data *irqd)
+{
+ mutex_lock(yu_arm_gpio_lock_param.lock);
+}
+
+static void mlxbf2_gpio_irq_bus_sync_unlock(struct irq_data *irqd)
+{
+ mutex_unlock(yu_arm_gpio_lock_param.lock);
+}
+
+static struct irq_chip mlxbf2_gpio_irq_chip = {
+ .name = "mlxbf2_gpio",
+ .irq_mask = mlxbf2_gpio_irq_mask,
+ .irq_unmask = mlxbf2_gpio_irq_unmask,
+ .irq_bus_lock = mlxbf2_gpio_irq_bus_lock,
+ .irq_bus_sync_unlock = mlxbf2_gpio_irq_bus_sync_unlock,
+};
+
/* BlueField-2 GPIO driver initialization routine. */
static int
mlxbf2_gpio_probe(struct platform_device *pdev)
--
2.30.2