[PATCH 5.4 011/222] Revert "gpio: thunderx: Switch to GPIOLIB_IRQCHIP"

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Kevin Hao <haokexin@gmail.com>

commit a564ac35d60564dd5b509e32afdc04e7aafee40e upstream.

This reverts commit a7fc89f9d5fcc10a5474cfe555f5a9e5df8b0f1f because
there are some bugs in this commit, and we don't have a simple way to
fix these bugs. So revert this commit to make the thunderx gpio work
on the stable kernel at least. We will switch to GPIOLIB_IRQCHIP
for thunderx gpio by following patches.

Fixes: a7fc89f9d5fc ("gpio: thunderx: Switch to GPIOLIB_IRQCHIP")
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Link: https://lore.kernel.org/r/20200114082821.14015-2-haokexin@gmail.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpio/Kconfig         |    1 
 drivers/gpio/gpio-thunderx.c |  163 ++++++++++++++++++++++++++++---------------
 2 files changed, 107 insertions(+), 57 deletions(-)

--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -546,7 +546,6 @@ config GPIO_THUNDERX
 	tristate "Cavium ThunderX/OCTEON-TX GPIO"
 	depends on ARCH_THUNDER || (64BIT && COMPILE_TEST)
 	depends on PCI_MSI
-	select GPIOLIB_IRQCHIP
 	select IRQ_DOMAIN_HIERARCHY
 	select IRQ_FASTEOI_HIERARCHY_HANDLERS
 	help
--- a/drivers/gpio/gpio-thunderx.c
+++ b/drivers/gpio/gpio-thunderx.c
@@ -53,6 +53,7 @@ struct thunderx_line {
 struct thunderx_gpio {
 	struct gpio_chip	chip;
 	u8 __iomem		*register_base;
+	struct irq_domain	*irqd;
 	struct msix_entry	*msix_entries;	/* per line MSI-X */
 	struct thunderx_line	*line_entries;	/* per line irq info */
 	raw_spinlock_t		lock;
@@ -282,60 +283,54 @@ static void thunderx_gpio_set_multiple(s
 	}
 }
 
-static void thunderx_gpio_irq_ack(struct irq_data *d)
+static void thunderx_gpio_irq_ack(struct irq_data *data)
 {
-	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
-	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
+	struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
 
 	writeq(GPIO_INTR_INTR,
-	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
+	       txline->txgpio->register_base + intr_reg(txline->line));
 }
 
-static void thunderx_gpio_irq_mask(struct irq_data *d)
+static void thunderx_gpio_irq_mask(struct irq_data *data)
 {
-	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
-	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
+	struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
 
 	writeq(GPIO_INTR_ENA_W1C,
-	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
+	       txline->txgpio->register_base + intr_reg(txline->line));
 }
 
-static void thunderx_gpio_irq_mask_ack(struct irq_data *d)
+static void thunderx_gpio_irq_mask_ack(struct irq_data *data)
 {
-	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
-	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
+	struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
 
 	writeq(GPIO_INTR_ENA_W1C | GPIO_INTR_INTR,
-	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
+	       txline->txgpio->register_base + intr_reg(txline->line));
 }
 
-static void thunderx_gpio_irq_unmask(struct irq_data *d)
+static void thunderx_gpio_irq_unmask(struct irq_data *data)
 {
-	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
-	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
+	struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
 
 	writeq(GPIO_INTR_ENA_W1S,
-	       txgpio->register_base + intr_reg(irqd_to_hwirq(d)));
+	       txline->txgpio->register_base + intr_reg(txline->line));
 }
 
-static int thunderx_gpio_irq_set_type(struct irq_data *d,
+static int thunderx_gpio_irq_set_type(struct irq_data *data,
 				      unsigned int flow_type)
 {
-	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
-	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
-	struct thunderx_line *txline =
-		&txgpio->line_entries[irqd_to_hwirq(d)];
+	struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
+	struct thunderx_gpio *txgpio = txline->txgpio;
 	u64 bit_cfg;
 
-	irqd_set_trigger_type(d, flow_type);
+	irqd_set_trigger_type(data, flow_type);
 
 	bit_cfg = txline->fil_bits | GPIO_BIT_CFG_INT_EN;
 
 	if (flow_type & IRQ_TYPE_EDGE_BOTH) {
-		irq_set_handler_locked(d, handle_fasteoi_ack_irq);
+		irq_set_handler_locked(data, handle_fasteoi_ack_irq);
 		bit_cfg |= GPIO_BIT_CFG_INT_TYPE;
 	} else {
-		irq_set_handler_locked(d, handle_fasteoi_mask_irq);
+		irq_set_handler_locked(data, handle_fasteoi_mask_irq);
 	}
 
 	raw_spin_lock(&txgpio->lock);
@@ -364,6 +359,33 @@ static void thunderx_gpio_irq_disable(st
 	irq_chip_disable_parent(data);
 }
 
+static int thunderx_gpio_irq_request_resources(struct irq_data *data)
+{
+	struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
+	struct thunderx_gpio *txgpio = txline->txgpio;
+	int r;
+
+	r = gpiochip_lock_as_irq(&txgpio->chip, txline->line);
+	if (r)
+		return r;
+
+	r = irq_chip_request_resources_parent(data);
+	if (r)
+		gpiochip_unlock_as_irq(&txgpio->chip, txline->line);
+
+	return r;
+}
+
+static void thunderx_gpio_irq_release_resources(struct irq_data *data)
+{
+	struct thunderx_line *txline = irq_data_get_irq_chip_data(data);
+	struct thunderx_gpio *txgpio = txline->txgpio;
+
+	irq_chip_release_resources_parent(data);
+
+	gpiochip_unlock_as_irq(&txgpio->chip, txline->line);
+}
+
 /*
  * Interrupts are chained from underlying MSI-X vectors.  We have
  * these irq_chip functions to be able to handle level triggering
@@ -380,22 +402,48 @@ static struct irq_chip thunderx_gpio_irq
 	.irq_unmask		= thunderx_gpio_irq_unmask,
 	.irq_eoi		= irq_chip_eoi_parent,
 	.irq_set_affinity	= irq_chip_set_affinity_parent,
+	.irq_request_resources	= thunderx_gpio_irq_request_resources,
+	.irq_release_resources	= thunderx_gpio_irq_release_resources,
 	.irq_set_type		= thunderx_gpio_irq_set_type,
 
 	.flags			= IRQCHIP_SET_TYPE_MASKED
 };
 
-static int thunderx_gpio_child_to_parent_hwirq(struct gpio_chip *gc,
-					       unsigned int child,
-					       unsigned int child_type,
-					       unsigned int *parent,
-					       unsigned int *parent_type)
+static int thunderx_gpio_irq_translate(struct irq_domain *d,
+				       struct irq_fwspec *fwspec,
+				       irq_hw_number_t *hwirq,
+				       unsigned int *type)
+{
+	struct thunderx_gpio *txgpio = d->host_data;
+
+	if (WARN_ON(fwspec->param_count < 2))
+		return -EINVAL;
+	if (fwspec->param[0] >= txgpio->chip.ngpio)
+		return -EINVAL;
+	*hwirq = fwspec->param[0];
+	*type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
+	return 0;
+}
+
+static int thunderx_gpio_irq_alloc(struct irq_domain *d, unsigned int virq,
+				   unsigned int nr_irqs, void *arg)
 {
-	struct thunderx_gpio *txgpio = gpiochip_get_data(gc);
+	struct thunderx_line *txline = arg;
 
-	*parent = txgpio->base_msi + (2 * child);
-	*parent_type = IRQ_TYPE_LEVEL_HIGH;
-	return 0;
+	return irq_domain_set_hwirq_and_chip(d, virq, txline->line,
+					     &thunderx_gpio_irq_chip, txline);
+}
+
+static const struct irq_domain_ops thunderx_gpio_irqd_ops = {
+	.alloc		= thunderx_gpio_irq_alloc,
+	.translate	= thunderx_gpio_irq_translate
+};
+
+static int thunderx_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
+{
+	struct thunderx_gpio *txgpio = gpiochip_get_data(chip);
+
+	return irq_find_mapping(txgpio->irqd, offset);
 }
 
 static int thunderx_gpio_probe(struct pci_dev *pdev,
@@ -405,7 +453,6 @@ static int thunderx_gpio_probe(struct pc
 	struct device *dev = &pdev->dev;
 	struct thunderx_gpio *txgpio;
 	struct gpio_chip *chip;
-	struct gpio_irq_chip *girq;
 	int ngpio, i;
 	int err = 0;
 
@@ -450,8 +497,8 @@ static int thunderx_gpio_probe(struct pc
 	}
 
 	txgpio->msix_entries = devm_kcalloc(dev,
-					    ngpio, sizeof(struct msix_entry),
-					    GFP_KERNEL);
+					  ngpio, sizeof(struct msix_entry),
+					  GFP_KERNEL);
 	if (!txgpio->msix_entries) {
 		err = -ENOMEM;
 		goto out;
@@ -492,6 +539,27 @@ static int thunderx_gpio_probe(struct pc
 	if (err < 0)
 		goto out;
 
+	/*
+	 * Push GPIO specific irqdomain on hierarchy created as a side
+	 * effect of the pci_enable_msix()
+	 */
+	txgpio->irqd = irq_domain_create_hierarchy(irq_get_irq_data(txgpio->msix_entries[0].vector)->domain,
+						   0, 0, of_node_to_fwnode(dev->of_node),
+						   &thunderx_gpio_irqd_ops, txgpio);
+	if (!txgpio->irqd) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	/* Push on irq_data and the domain for each line. */
+	for (i = 0; i < ngpio; i++) {
+		err = irq_domain_push_irq(txgpio->irqd,
+					  txgpio->msix_entries[i].vector,
+					  &txgpio->line_entries[i]);
+		if (err < 0)
+			dev_err(dev, "irq_domain_push_irq: %d\n", err);
+	}
+
 	chip->label = KBUILD_MODNAME;
 	chip->parent = dev;
 	chip->owner = THIS_MODULE;
@@ -506,28 +574,11 @@ static int thunderx_gpio_probe(struct pc
 	chip->set = thunderx_gpio_set;
 	chip->set_multiple = thunderx_gpio_set_multiple;
 	chip->set_config = thunderx_gpio_set_config;
-	girq = &chip->irq;
-	girq->chip = &thunderx_gpio_irq_chip;
-	girq->fwnode = of_node_to_fwnode(dev->of_node);
-	girq->parent_domain =
-		irq_get_irq_data(txgpio->msix_entries[0].vector)->domain;
-	girq->child_to_parent_hwirq = thunderx_gpio_child_to_parent_hwirq;
-	girq->handler = handle_bad_irq;
-	girq->default_type = IRQ_TYPE_NONE;
-
+	chip->to_irq = thunderx_gpio_to_irq;
 	err = devm_gpiochip_add_data(dev, chip, txgpio);
 	if (err)
 		goto out;
 
-	/* Push on irq_data and the domain for each line. */
-	for (i = 0; i < ngpio; i++) {
-		err = irq_domain_push_irq(chip->irq.domain,
-					  txgpio->msix_entries[i].vector,
-					  chip);
-		if (err < 0)
-			dev_err(dev, "irq_domain_push_irq: %d\n", err);
-	}
-
 	dev_info(dev, "ThunderX GPIO: %d lines with base %d.\n",
 		 ngpio, chip->base);
 	return 0;
@@ -542,10 +593,10 @@ static void thunderx_gpio_remove(struct
 	struct thunderx_gpio *txgpio = pci_get_drvdata(pdev);
 
 	for (i = 0; i < txgpio->chip.ngpio; i++)
-		irq_domain_pop_irq(txgpio->chip.irq.domain,
+		irq_domain_pop_irq(txgpio->irqd,
 				   txgpio->msix_entries[i].vector);
 
-	irq_domain_remove(txgpio->chip.irq.domain);
+	irq_domain_remove(txgpio->irqd);
 
 	pci_set_drvdata(pdev, NULL);
 }