[PATCH v4 0/2] gpio: mlxbf2: Introduce proper interrupt handling

[PATCH v4 0/2] gpio: mlxbf2: Introduce proper interrupt handling

[Asmaa Mnebhi]

This is a follow up on a discussion regarding
proper handling of GPIO interrupts within the
gpio-mlxbf2.c driver.

Link to discussion:
https://lore.kernel.org/netdev/20210816115953.72533-7-andriy.shevchenko@linux.intel.com/T/

Patch 1 adds support to a GPIO IRQ handler in gpio-mlxbf2.c.
Patch 2 is a follow up removal of custom GPIO IRQ handling
from the mlxbf_gige driver and replacing it with a simple
IRQ request. The ACPI table for the mlxbf_gige driver is
responsible for instantiating the PHY GPIO interrupt via
GpioInt.

Andy Shevchenko, could you please review this patch series.

v4 vs. v3 patch:
- Remove IRQ_TYPE_LEVEL* from mlxbf2_gpio_irq_set_type
  since LEVEL interrupts are not supported by internal
  BlueField GPIO HW.

Asmaa Mnebhi (2):
  gpio: mlxbf2: Introduce IRQ support
  net: mellanox: mlxbf_gige: Replace non-standard interrupt handling

 drivers/gpio/gpio-mlxbf2.c                    | 147 +++++++++++-
 .../net/ethernet/mellanox/mlxbf_gige/Makefile |   1 -
 .../ethernet/mellanox/mlxbf_gige/mlxbf_gige.h |  12 -
 .../mellanox/mlxbf_gige/mlxbf_gige_gpio.c     | 212 ------------------
 .../mellanox/mlxbf_gige/mlxbf_gige_main.c     |  22 +-
 5 files changed, 154 insertions(+), 240 deletions(-)
 delete mode 100644 drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_gpio.c

-- 
2.30.1

[PATCH v4 1/2] gpio: mlxbf2: Introduce IRQ support

[Asmaa Mnebhi]

Introduce standard IRQ handling in the gpio-mlxbf2.c
driver.

Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
---
 drivers/gpio/gpio-mlxbf2.c | 147 ++++++++++++++++++++++++++++++++++++-
 1 file changed, 145 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/gpio-mlxbf2.c b/drivers/gpio/gpio-mlxbf2.c
index 177d03ef4529..3d89912a05b8 100644
--- a/drivers/gpio/gpio-mlxbf2.c
+++ b/drivers/gpio/gpio-mlxbf2.c
@@ -1,9 +1,14 @@
 // SPDX-License-Identifier: GPL-2.0
 
+/*
+ * Copyright (C) 2020-2021 NVIDIA CORPORATION & AFFILIATES
+ */
+
 #include <linux/bitfield.h>
 #include <linux/bitops.h>
 #include <linux/device.h>
 #include <linux/gpio/driver.h>
+#include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/ioport.h>
 #include <linux/kernel.h>
@@ -43,9 +48,14 @@
 #define YU_GPIO_MODE0			0x0c
 #define YU_GPIO_DATASET			0x14
 #define YU_GPIO_DATACLEAR		0x18
+#define YU_GPIO_CAUSE_RISE_EN		0x44
+#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;
@@ -55,6 +65,7 @@ struct mlxbf2_gpio_context_save_regs {
 /* BlueField-2 gpio block context structure. */
 struct mlxbf2_gpio_context {
 	struct gpio_chip gc;
+	struct irq_chip irq_chip;
 
 	/* YU GPIO blocks address */
 	void __iomem *gpio_io;
@@ -218,15 +229,114 @@ static int mlxbf2_gpio_direction_output(struct gpio_chip *chip,
 	return ret;
 }
 
+static void mlxbf2_gpio_irq_enable(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);
+	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);
+
+	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 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);
+	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 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);
+	writel(pending, gs->gpio_io + YU_GPIO_CAUSE_OR_CLRCAUSE);
+
+	for_each_set_bit(level, &pending, gc->ngpio) {
+		int gpio_irq = irq_find_mapping(gc->irq.domain, level);
+		generic_handle_irq(gpio_irq);
+	}
+
+	return IRQ_RETVAL(pending);
+}
+
+static int
+mlxbf2_gpio_irq_set_type(struct irq_data *irqd, unsigned int type)
+{
+	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);
+	unsigned long flags;
+	bool fall = false;
+	bool rise = false;
+	u32 val;
+
+	switch (type & IRQ_TYPE_SENSE_MASK) {
+	case IRQ_TYPE_EDGE_BOTH:
+		fall = true;
+		rise = true;
+		break;
+	case IRQ_TYPE_EDGE_RISING:
+		rise = true;
+		break;
+	case IRQ_TYPE_EDGE_FALLING:
+		fall = true;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	spin_lock_irqsave(&gs->gc.bgpio_lock, flags);
+	if (fall) {
+		val = readl(gs->gpio_io + YU_GPIO_CAUSE_FALL_EN);
+		val |= BIT(offset);
+		writel(val, gs->gpio_io + YU_GPIO_CAUSE_FALL_EN);
+	}
+
+	if (rise) {
+		val = readl(gs->gpio_io + YU_GPIO_CAUSE_RISE_EN);
+		val |= BIT(offset);
+		writel(val, gs->gpio_io + YU_GPIO_CAUSE_RISE_EN);
+	}
+	spin_unlock_irqrestore(&gs->gc.bgpio_lock, flags);
+
+	return 0;
+}
+
 /* BlueField-2 GPIO driver initialization routine. */
 static int
 mlxbf2_gpio_probe(struct platform_device *pdev)
 {
 	struct mlxbf2_gpio_context *gs;
 	struct device *dev = &pdev->dev;
+	struct gpio_irq_chip *girq;
 	struct gpio_chip *gc;
 	unsigned int npins;
-	int ret;
+	const char *name;
+	int ret, irq;
+
+	name = dev_name(dev);
 
 	gs = devm_kzalloc(dev, sizeof(*gs), GFP_KERNEL);
 	if (!gs)
@@ -256,11 +366,44 @@ mlxbf2_gpio_probe(struct platform_device *pdev)
 			NULL,
 			0);
 
+	if (ret) {
+		dev_err(dev, "bgpio_init failed\n");
+		return ret;
+	}
+
 	gc->direction_input = mlxbf2_gpio_direction_input;
 	gc->direction_output = mlxbf2_gpio_direction_output;
 	gc->ngpio = npins;
 	gc->owner = THIS_MODULE;
 
+	irq = platform_get_irq(pdev, 0);
+	if (irq >= 0) {
+		gs->irq_chip.name = name;
+		gs->irq_chip.irq_set_type = mlxbf2_gpio_irq_set_type;
+		gs->irq_chip.irq_enable = mlxbf2_gpio_irq_enable;
+		gs->irq_chip.irq_disable = mlxbf2_gpio_irq_disable;
+
+		girq = &gs->gc.irq;
+		girq->chip = &gs->irq_chip;
+		girq->handler = handle_simple_irq;
+		girq->default_type = IRQ_TYPE_NONE;
+		/* This will let us handle the parent IRQ in the driver */
+		girq->num_parents = 0;
+		girq->parents = NULL;
+		girq->parent_handler = NULL;
+
+		/*
+		 * Directly request the irq here instead of passing
+		 * a flow-handler because the irq is shared.
+		 */
+		ret = devm_request_irq(dev, irq, mlxbf2_gpio_irq_handler,
+				       IRQF_SHARED, name, gs);
+		if (ret) {
+			dev_err(dev, "failed to request IRQ");
+			return ret;
+		}
+	}
+
 	platform_set_drvdata(pdev, gs);
 
 	ret = devm_gpiochip_add_data(dev, &gs->gc, gs);
@@ -315,5 +458,5 @@ static struct platform_driver mlxbf2_gpio_driver = {
 module_platform_driver(mlxbf2_gpio_driver);
 
 MODULE_DESCRIPTION("Mellanox BlueField-2 GPIO Driver");
-MODULE_AUTHOR("Mellanox Technologies");
+MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
 MODULE_LICENSE("GPL v2");
-- 
2.30.1

[PATCH v4 2/2] net: mellanox: mlxbf_gige: Replace non-standard interrupt handling

[Asmaa Mnebhi]

Since the GPIO driver (gpio-mlxbf2.c) supports interrupt
handling, replace the custom routine with simple IRQ
request.

Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
---
 .../net/ethernet/mellanox/mlxbf_gige/Makefile |   1 -
 .../ethernet/mellanox/mlxbf_gige/mlxbf_gige.h |  12 -
 .../mellanox/mlxbf_gige/mlxbf_gige_gpio.c     | 212 ------------------
 .../mellanox/mlxbf_gige/mlxbf_gige_main.c     |  22 +-
 4 files changed, 9 insertions(+), 238 deletions(-)
 delete mode 100644 drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_gpio.c

diff --git a/drivers/net/ethernet/mellanox/mlxbf_gige/Makefile b/drivers/net/ethernet/mellanox/mlxbf_gige/Makefile
index e57c1375f236..a97c2bef846b 100644
--- a/drivers/net/ethernet/mellanox/mlxbf_gige/Makefile
+++ b/drivers/net/ethernet/mellanox/mlxbf_gige/Makefile
@@ -3,7 +3,6 @@
 obj-$(CONFIG_MLXBF_GIGE) += mlxbf_gige.o
 
 mlxbf_gige-y := mlxbf_gige_ethtool.o \
-		mlxbf_gige_gpio.o \
 		mlxbf_gige_intr.o \
 		mlxbf_gige_main.o \
 		mlxbf_gige_mdio.o \
diff --git a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige.h b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige.h
index e3509e69ed1c..86826a70f9dd 100644
--- a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige.h
+++ b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige.h
@@ -51,11 +51,6 @@
 #define MLXBF_GIGE_ERROR_INTR_IDX       0
 #define MLXBF_GIGE_RECEIVE_PKT_INTR_IDX 1
 #define MLXBF_GIGE_LLU_PLU_INTR_IDX     2
-#define MLXBF_GIGE_PHY_INT_N            3
-
-#define MLXBF_GIGE_MDIO_DEFAULT_PHY_ADDR 0x3
-
-#define MLXBF_GIGE_DEFAULT_PHY_INT_GPIO 12
 
 struct mlxbf_gige_stats {
 	u64 hw_access_errors;
@@ -81,11 +76,7 @@ struct mlxbf_gige {
 	struct platform_device *pdev;
 	void __iomem *mdio_io;
 	struct mii_bus *mdiobus;
-	void __iomem *gpio_io;
-	struct irq_domain *irqdomain;
-	u32 phy_int_gpio_mask;
 	spinlock_t lock;      /* for packet processing indices */
-	spinlock_t gpio_lock; /* for GPIO bus access */
 	u16 rx_q_entries;
 	u16 tx_q_entries;
 	u64 *tx_wqe_base;
@@ -184,7 +175,4 @@ int mlxbf_gige_poll(struct napi_struct *napi, int budget);
 extern const struct ethtool_ops mlxbf_gige_ethtool_ops;
 void mlxbf_gige_update_tx_wqe_next(struct mlxbf_gige *priv);
 
-int mlxbf_gige_gpio_init(struct platform_device *pdev, struct mlxbf_gige *priv);
-void mlxbf_gige_gpio_free(struct mlxbf_gige *priv);
-
 #endif /* !defined(__MLXBF_GIGE_H__) */
diff --git a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_gpio.c b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_gpio.c
deleted file mode 100644
index a8d966db5715..000000000000
--- a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_gpio.c
+++ /dev/null
@@ -1,212 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only OR BSD-3-Clause
-
-/* Initialize and handle GPIO interrupt triggered by INT_N PHY signal.
- * This GPIO interrupt triggers the PHY state machine to bring the link
- * up/down.
- *
- * Copyright (C) 2021 NVIDIA CORPORATION & AFFILIATES
- */
-
-#include <linux/acpi.h>
-#include <linux/bitfield.h>
-#include <linux/device.h>
-#include <linux/err.h>
-#include <linux/gpio/driver.h>
-#include <linux/interrupt.h>
-#include <linux/io.h>
-#include <linux/irq.h>
-#include <linux/irqdomain.h>
-#include <linux/irqreturn.h>
-#include <linux/platform_device.h>
-#include <linux/property.h>
-
-#include "mlxbf_gige.h"
-#include "mlxbf_gige_regs.h"
-
-#define MLXBF_GIGE_GPIO_CAUSE_FALL_EN		0x48
-#define MLXBF_GIGE_GPIO_CAUSE_OR_CAUSE_EVTEN0	0x80
-#define MLXBF_GIGE_GPIO_CAUSE_OR_EVTEN0		0x94
-#define MLXBF_GIGE_GPIO_CAUSE_OR_CLRCAUSE	0x98
-
-static void mlxbf_gige_gpio_enable(struct mlxbf_gige *priv)
-{
-	unsigned long flags;
-	u32 val;
-
-	spin_lock_irqsave(&priv->gpio_lock, flags);
-	val = readl(priv->gpio_io + MLXBF_GIGE_GPIO_CAUSE_OR_CLRCAUSE);
-	val |= priv->phy_int_gpio_mask;
-	writel(val, priv->gpio_io + MLXBF_GIGE_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(priv->gpio_io + MLXBF_GIGE_GPIO_CAUSE_FALL_EN);
-	val |= priv->phy_int_gpio_mask;
-	writel(val, priv->gpio_io + MLXBF_GIGE_GPIO_CAUSE_FALL_EN);
-
-	/* Enable PHY interrupt by setting the priority level */
-	val = readl(priv->gpio_io + MLXBF_GIGE_GPIO_CAUSE_OR_EVTEN0);
-	val |= priv->phy_int_gpio_mask;
-	writel(val, priv->gpio_io + MLXBF_GIGE_GPIO_CAUSE_OR_EVTEN0);
-	spin_unlock_irqrestore(&priv->gpio_lock, flags);
-}
-
-static void mlxbf_gige_gpio_disable(struct mlxbf_gige *priv)
-{
-	unsigned long flags;
-	u32 val;
-
-	spin_lock_irqsave(&priv->gpio_lock, flags);
-	val = readl(priv->gpio_io + MLXBF_GIGE_GPIO_CAUSE_OR_EVTEN0);
-	val &= ~priv->phy_int_gpio_mask;
-	writel(val, priv->gpio_io + MLXBF_GIGE_GPIO_CAUSE_OR_EVTEN0);
-	spin_unlock_irqrestore(&priv->gpio_lock, flags);
-}
-
-static irqreturn_t mlxbf_gige_gpio_handler(int irq, void *ptr)
-{
-	struct mlxbf_gige *priv;
-	u32 val;
-
-	priv = ptr;
-
-	/* Check if this interrupt is from PHY device.
-	 * Return if it is not.
-	 */
-	val = readl(priv->gpio_io + MLXBF_GIGE_GPIO_CAUSE_OR_CAUSE_EVTEN0);
-	if (!(val & priv->phy_int_gpio_mask))
-		return IRQ_NONE;
-
-	/* Clear interrupt when done, otherwise, no further interrupt
-	 * will be triggered.
-	 */
-	val = readl(priv->gpio_io + MLXBF_GIGE_GPIO_CAUSE_OR_CLRCAUSE);
-	val |= priv->phy_int_gpio_mask;
-	writel(val, priv->gpio_io + MLXBF_GIGE_GPIO_CAUSE_OR_CLRCAUSE);
-
-	generic_handle_irq(priv->phy_irq);
-
-	return IRQ_HANDLED;
-}
-
-static void mlxbf_gige_gpio_mask(struct irq_data *irqd)
-{
-	struct mlxbf_gige *priv = irq_data_get_irq_chip_data(irqd);
-
-	mlxbf_gige_gpio_disable(priv);
-}
-
-static void mlxbf_gige_gpio_unmask(struct irq_data *irqd)
-{
-	struct mlxbf_gige *priv = irq_data_get_irq_chip_data(irqd);
-
-	mlxbf_gige_gpio_enable(priv);
-}
-
-static struct irq_chip mlxbf_gige_gpio_chip = {
-	.name			= "mlxbf_gige_phy",
-	.irq_mask		= mlxbf_gige_gpio_mask,
-	.irq_unmask		= mlxbf_gige_gpio_unmask,
-};
-
-static int mlxbf_gige_gpio_domain_map(struct irq_domain *d,
-				      unsigned int irq,
-				      irq_hw_number_t hwirq)
-{
-	irq_set_chip_data(irq, d->host_data);
-	irq_set_chip_and_handler(irq, &mlxbf_gige_gpio_chip, handle_simple_irq);
-	irq_set_noprobe(irq);
-
-	return 0;
-}
-
-static const struct irq_domain_ops mlxbf_gige_gpio_domain_ops = {
-	.map    = mlxbf_gige_gpio_domain_map,
-	.xlate	= irq_domain_xlate_twocell,
-};
-
-#ifdef CONFIG_ACPI
-static int mlxbf_gige_gpio_resources(struct acpi_resource *ares,
-				     void *data)
-{
-	struct acpi_resource_gpio *gpio;
-	u32 *phy_int_gpio = data;
-
-	if (ares->type == ACPI_RESOURCE_TYPE_GPIO) {
-		gpio = &ares->data.gpio;
-		*phy_int_gpio = gpio->pin_table[0];
-	}
-
-	return 1;
-}
-#endif
-
-void mlxbf_gige_gpio_free(struct mlxbf_gige *priv)
-{
-	irq_dispose_mapping(priv->phy_irq);
-	irq_domain_remove(priv->irqdomain);
-}
-
-int mlxbf_gige_gpio_init(struct platform_device *pdev,
-			 struct mlxbf_gige *priv)
-{
-	struct device *dev = &pdev->dev;
-	struct resource *res;
-	u32 phy_int_gpio = 0;
-	int ret;
-
-	LIST_HEAD(resources);
-
-	res = platform_get_resource(pdev, IORESOURCE_MEM, MLXBF_GIGE_RES_GPIO0);
-	if (!res)
-		return -ENODEV;
-
-	priv->gpio_io = devm_ioremap(dev, res->start, resource_size(res));
-	if (!priv->gpio_io)
-		return -ENOMEM;
-
-#ifdef CONFIG_ACPI
-	ret = acpi_dev_get_resources(ACPI_COMPANION(dev),
-				     &resources, mlxbf_gige_gpio_resources,
-				     &phy_int_gpio);
-	acpi_dev_free_resource_list(&resources);
-	if (ret < 0 || !phy_int_gpio) {
-		dev_err(dev, "Error retrieving the gpio phy pin");
-		return -EINVAL;
-	}
-#endif
-
-	priv->phy_int_gpio_mask = BIT(phy_int_gpio);
-
-	mlxbf_gige_gpio_disable(priv);
-
-	priv->hw_phy_irq = platform_get_irq(pdev, MLXBF_GIGE_PHY_INT_N);
-
-	priv->irqdomain = irq_domain_add_simple(NULL, 1, 0,
-						&mlxbf_gige_gpio_domain_ops,
-						priv);
-	if (!priv->irqdomain) {
-		dev_err(dev, "Failed to add IRQ domain\n");
-		return -ENOMEM;
-	}
-
-	priv->phy_irq = irq_create_mapping(priv->irqdomain, 0);
-	if (!priv->phy_irq) {
-		irq_domain_remove(priv->irqdomain);
-		priv->irqdomain = NULL;
-		dev_err(dev, "Error mapping PHY IRQ\n");
-		return -EINVAL;
-	}
-
-	ret = devm_request_irq(dev, priv->hw_phy_irq, mlxbf_gige_gpio_handler,
-			       IRQF_ONESHOT | IRQF_SHARED, "mlxbf_gige_phy", priv);
-	if (ret) {
-		dev_err(dev, "Failed to request PHY IRQ");
-		mlxbf_gige_gpio_free(priv);
-		return ret;
-	}
-
-	return ret;
-}
diff --git a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c
index 3e85b17f5857..4382ec8f7d64 100644
--- a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c
+++ b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_main.c
@@ -273,8 +273,8 @@ static int mlxbf_gige_probe(struct platform_device *pdev)
 	void __iomem *llu_base;
 	void __iomem *plu_base;
 	void __iomem *base;
+	int addr, phy_irq;
 	u64 control;
-	int addr;
 	int err;
 
 	base = devm_platform_ioremap_resource(pdev, MLXBF_GIGE_RES_MAC);
@@ -309,20 +309,12 @@ static int mlxbf_gige_probe(struct platform_device *pdev)
 	priv->pdev = pdev;
 
 	spin_lock_init(&priv->lock);
-	spin_lock_init(&priv->gpio_lock);
 
 	/* Attach MDIO device */
 	err = mlxbf_gige_mdio_probe(pdev, priv);
 	if (err)
 		return err;
 
-	err = mlxbf_gige_gpio_init(pdev, priv);
-	if (err) {
-		dev_err(&pdev->dev, "PHY IRQ initialization failed\n");
-		mlxbf_gige_mdio_remove(priv);
-		return -ENODEV;
-	}
-
 	priv->base = base;
 	priv->llu_base = llu_base;
 	priv->plu_base = plu_base;
@@ -343,6 +335,12 @@ static int mlxbf_gige_probe(struct platform_device *pdev)
 	priv->rx_irq = platform_get_irq(pdev, MLXBF_GIGE_RECEIVE_PKT_INTR_IDX);
 	priv->llu_plu_irq = platform_get_irq(pdev, MLXBF_GIGE_LLU_PLU_INTR_IDX);
 
+	phy_irq = acpi_dev_gpio_irq_get_by(ACPI_COMPANION(&pdev->dev), "phy-gpios", 0);
+	if (phy_irq < 0) {
+		dev_err(&pdev->dev, "Error getting PHY irq. Use polling instead");
+		phy_irq = PHY_POLL;
+	}
+
 	phydev = phy_find_first(priv->mdiobus);
 	if (!phydev) {
 		err = -ENODEV;
@@ -350,8 +348,8 @@ static int mlxbf_gige_probe(struct platform_device *pdev)
 	}
 
 	addr = phydev->mdio.addr;
-	priv->mdiobus->irq[addr] = priv->phy_irq;
-	phydev->irq = priv->phy_irq;
+	priv->mdiobus->irq[addr] = phy_irq;
+	phydev->irq = phy_irq;
 
 	err = phy_connect_direct(netdev, phydev,
 				 mlxbf_gige_adjust_link,
@@ -387,7 +385,6 @@ static int mlxbf_gige_probe(struct platform_device *pdev)
 	return 0;
 
 out:
-	mlxbf_gige_gpio_free(priv);
 	mlxbf_gige_mdio_remove(priv);
 	return err;
 }
@@ -398,7 +395,6 @@ static int mlxbf_gige_remove(struct platform_device *pdev)
 
 	unregister_netdev(priv->netdev);
 	phy_disconnect(priv->netdev->phydev);
-	mlxbf_gige_gpio_free(priv);
 	mlxbf_gige_mdio_remove(priv);
 	platform_set_drvdata(pdev, NULL);
 
-- 
2.30.1

Re: [PATCH v4 1/2] gpio: mlxbf2: Introduce IRQ support

[Bartosz Golaszewski]

On Fri, Oct 8, 2021 at 4:50 PM Asmaa Mnebhi <asmaa@nvidia.com> wrote:
>
> Introduce standard IRQ handling in the gpio-mlxbf2.c
> driver.
>
> Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
> ---
>  drivers/gpio/gpio-mlxbf2.c | 147 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 145 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpio/gpio-mlxbf2.c b/drivers/gpio/gpio-mlxbf2.c
> index 177d03ef4529..3d89912a05b8 100644
> --- a/drivers/gpio/gpio-mlxbf2.c
> +++ b/drivers/gpio/gpio-mlxbf2.c
> @@ -1,9 +1,14 @@
>  // SPDX-License-Identifier: GPL-2.0
>
> +/*
> + * Copyright (C) 2020-2021 NVIDIA CORPORATION & AFFILIATES
> + */
> +
>  #include <linux/bitfield.h>
>  #include <linux/bitops.h>
>  #include <linux/device.h>
>  #include <linux/gpio/driver.h>
> +#include <linux/interrupt.h>
>  #include <linux/io.h>
>  #include <linux/ioport.h>
>  #include <linux/kernel.h>
> @@ -43,9 +48,14 @@
>  #define YU_GPIO_MODE0                  0x0c
>  #define YU_GPIO_DATASET                        0x14
>  #define YU_GPIO_DATACLEAR              0x18
> +#define YU_GPIO_CAUSE_RISE_EN          0x44
> +#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;
> @@ -55,6 +65,7 @@ struct mlxbf2_gpio_context_save_regs {
>  /* BlueField-2 gpio block context structure. */
>  struct mlxbf2_gpio_context {
>         struct gpio_chip gc;
> +       struct irq_chip irq_chip;
>
>         /* YU GPIO blocks address */
>         void __iomem *gpio_io;
> @@ -218,15 +229,114 @@ static int mlxbf2_gpio_direction_output(struct gpio_chip *chip,
>         return ret;
>  }
>
> +static void mlxbf2_gpio_irq_enable(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);
> +       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);
> +
> +       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 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);
> +       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 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);
> +       writel(pending, gs->gpio_io + YU_GPIO_CAUSE_OR_CLRCAUSE);
> +
> +       for_each_set_bit(level, &pending, gc->ngpio) {
> +               int gpio_irq = irq_find_mapping(gc->irq.domain, level);
> +               generic_handle_irq(gpio_irq);
> +       }
> +
> +       return IRQ_RETVAL(pending);
> +}
> +
> +static int
> +mlxbf2_gpio_irq_set_type(struct irq_data *irqd, unsigned int type)
> +{
> +       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);
> +       unsigned long flags;
> +       bool fall = false;
> +       bool rise = false;
> +       u32 val;
> +
> +       switch (type & IRQ_TYPE_SENSE_MASK) {
> +       case IRQ_TYPE_EDGE_BOTH:
> +               fall = true;
> +               rise = true;
> +               break;
> +       case IRQ_TYPE_EDGE_RISING:
> +               rise = true;
> +               break;
> +       case IRQ_TYPE_EDGE_FALLING:
> +               fall = true;
> +               break;
> +       default:
> +               return -EINVAL;
> +       }
> +
> +       spin_lock_irqsave(&gs->gc.bgpio_lock, flags);
> +       if (fall) {
> +               val = readl(gs->gpio_io + YU_GPIO_CAUSE_FALL_EN);
> +               val |= BIT(offset);
> +               writel(val, gs->gpio_io + YU_GPIO_CAUSE_FALL_EN);
> +       }
> +
> +       if (rise) {
> +               val = readl(gs->gpio_io + YU_GPIO_CAUSE_RISE_EN);
> +               val |= BIT(offset);
> +               writel(val, gs->gpio_io + YU_GPIO_CAUSE_RISE_EN);
> +       }
> +       spin_unlock_irqrestore(&gs->gc.bgpio_lock, flags);
> +
> +       return 0;
> +}
> +
>  /* BlueField-2 GPIO driver initialization routine. */
>  static int
>  mlxbf2_gpio_probe(struct platform_device *pdev)
>  {
>         struct mlxbf2_gpio_context *gs;
>         struct device *dev = &pdev->dev;
> +       struct gpio_irq_chip *girq;
>         struct gpio_chip *gc;
>         unsigned int npins;
> -       int ret;
> +       const char *name;
> +       int ret, irq;
> +
> +       name = dev_name(dev);
>
>         gs = devm_kzalloc(dev, sizeof(*gs), GFP_KERNEL);
>         if (!gs)
> @@ -256,11 +366,44 @@ mlxbf2_gpio_probe(struct platform_device *pdev)
>                         NULL,
>                         0);
>
> +       if (ret) {
> +               dev_err(dev, "bgpio_init failed\n");
> +               return ret;
> +       }

This is a correct fix but it should be sent as a fix aimed for stable
in a separate branch, as we want that to be backported.

Other than that it looks good to me, which tree do you want it to go through?

Bart

> +
>         gc->direction_input = mlxbf2_gpio_direction_input;
>         gc->direction_output = mlxbf2_gpio_direction_output;
>         gc->ngpio = npins;
>         gc->owner = THIS_MODULE;
>
> +       irq = platform_get_irq(pdev, 0);
> +       if (irq >= 0) {
> +               gs->irq_chip.name = name;
> +               gs->irq_chip.irq_set_type = mlxbf2_gpio_irq_set_type;
> +               gs->irq_chip.irq_enable = mlxbf2_gpio_irq_enable;
> +               gs->irq_chip.irq_disable = mlxbf2_gpio_irq_disable;
> +
> +               girq = &gs->gc.irq;
> +               girq->chip = &gs->irq_chip;
> +               girq->handler = handle_simple_irq;
> +               girq->default_type = IRQ_TYPE_NONE;
> +               /* This will let us handle the parent IRQ in the driver */
> +               girq->num_parents = 0;
> +               girq->parents = NULL;
> +               girq->parent_handler = NULL;
> +
> +               /*
> +                * Directly request the irq here instead of passing
> +                * a flow-handler because the irq is shared.
> +                */
> +               ret = devm_request_irq(dev, irq, mlxbf2_gpio_irq_handler,
> +                                      IRQF_SHARED, name, gs);
> +               if (ret) {
> +                       dev_err(dev, "failed to request IRQ");
> +                       return ret;
> +               }
> +       }
> +
>         platform_set_drvdata(pdev, gs);
>
>         ret = devm_gpiochip_add_data(dev, &gs->gc, gs);
> @@ -315,5 +458,5 @@ static struct platform_driver mlxbf2_gpio_driver = {
>  module_platform_driver(mlxbf2_gpio_driver);
>
>  MODULE_DESCRIPTION("Mellanox BlueField-2 GPIO Driver");
> -MODULE_AUTHOR("Mellanox Technologies");
> +MODULE_AUTHOR("Asmaa Mnebhi <asmaa@nvidia.com>");
>  MODULE_LICENSE("GPL v2");
> --
> 2.30.1
>

RE: [PATCH v4 1/2] gpio: mlxbf2: Introduce IRQ support

[Asmaa Mnebhi]

>  /* BlueField-2 GPIO driver initialization routine. */  static int  
> mlxbf2_gpio_probe(struct platform_device *pdev)  {
>         struct mlxbf2_gpio_context *gs;
>         struct device *dev = &pdev->dev;
> +       struct gpio_irq_chip *girq;
>         struct gpio_chip *gc;
>         unsigned int npins;
> -       int ret;
> +       const char *name;
> +       int ret, irq;
> +
> +       name = dev_name(dev);
>
>         gs = devm_kzalloc(dev, sizeof(*gs), GFP_KERNEL);
>         if (!gs)
> @@ -256,11 +366,44 @@ mlxbf2_gpio_probe(struct platform_device *pdev)
>                         NULL,
>                         0);
>
> +       if (ret) {
> +               dev_err(dev, "bgpio_init failed\n");
> +               return ret;
> +       }

> This is a correct fix but it should be sent as a fix aimed for stable in a separate branch, as we want that to be backported.
Ok! So I will send v5 patch, leaving these 4 lines out, then will add this small fix to a separate patch aimed to the stable branch.

> Other than that it looks good to me, which tree do you want it to go through?

Since the mlxbf-gige driver is dependent on this commit, I would like to push both this gpio
commit and
"[PATCH v4 2/2] net: mellanox: mlxbf_gige: Replace non-standard interrupt handling"
to the same tree/branch.

I apologize I am not very familiar with the push process when 2 dependent commits
target different drivers. So any input is greatly appreciated!
Since the mlxbf_gige driver is targeting the net master branch, would it be possible to push
The Gpio change as well to net? 
If this is not possible, maybe we can push the commit to linux-gpio master and
The mlxbf_gige to the net branch. But we will need to sync the timing for when both
requests go to the mainline.

David Miller, Andrew Lunn, I know you have acked/reviewed v1 and v2 patches for
the mlxbf_gige driver. I just want to make sure you are still ok with this implementation.
I mentioned in a previous email that our management/product manager approved using 
PHY interrupt instead of polling.

Thank you.
Asmaa