gpio: Initialize the irqchip valid_mask with a callback

After changing the valid_mask for the struct gpio_chip
to detect the need and presence of a valid mask with the
presence of a .init_valid_mask() callback to fill it in,
we augment the gpio_irq_chip to use the same logic.

Switch all driver using the gpio_irq_chio valid_mask
over to this new method.

This makes sure the valid_mask for the gpio_irq_chip gets
filled in when we add the gpio_chip, which makes it a
little easier to switch over drivers using the old
way of setting up gpio_irq_chip over to the new method
of passing the gpio_irq_chip along with the gpio_chip.
(See drivers/gpio/TODO for details.)

Cc: Joel Stanley <joel@jms.id.au>
Cc: Thierry Reding <treding@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
Link: https://lore.kernel.org/r/20190904140104.32426-1-linus.walleij@linaro.org

drivers/gpio/gpio-aspeed.c

@@ -689,8 +689,11 @@ static struct irq_chip aspeed_gpio_irqchip = {
 	.irq_set_type	= aspeed_gpio_set_type,
 };
 
-static void set_irq_valid_mask(struct aspeed_gpio *gpio)
+static void aspeed_init_irq_valid_mask(struct gpio_chip *gc,
+				       unsigned long *valid_mask,
+				       unsigned int ngpios)
 {
+	struct aspeed_gpio *gpio = gpiochip_get_data(gc);
 	const struct aspeed_bank_props *props = gpio->config->props;
 
 	while (!is_bank_props_sentinel(props)) {
@@ -704,7 +707,7 @@ static void set_irq_valid_mask(struct aspeed_gpio *gpio)
 			if (i >= gpio->config->nr_gpios)
 				break;
 
-			clear_bit(i, gpio->chip.irq.valid_mask);
+			clear_bit(i, valid_mask);
 		}
 
 		props++;
@@ -1203,7 +1206,7 @@ static int __init aspeed_gpio_probe(struct platform_device *pdev)
 		girq->parents[0] = gpio->irq;
 		girq->default_type = IRQ_TYPE_NONE;
 		girq->handler = handle_bad_irq;
-		girq->need_valid_mask = true;
+		girq->init_valid_mask = aspeed_init_irq_valid_mask;
 	}
 
 	gpio->offset_timer =
@@ -1215,10 +1218,6 @@ static int __init aspeed_gpio_probe(struct platform_device *pdev)
 	if (rc < 0)
 		return rc;
 
-	/* Now the valid mask is allocated */
-	if (gpio->irq)
-		set_irq_valid_mask(gpio);
-
 	return 0;
 }
 

drivers/gpio/gpio-stmpe.c

@@ -429,6 +429,23 @@ static irqreturn_t stmpe_gpio_irq(int irq, void *dev)
 	return IRQ_HANDLED;
 }
 
+static void stmpe_init_irq_valid_mask(struct gpio_chip *gc,
+				      unsigned long *valid_mask,
+				      unsigned int ngpios)
+{
+	struct stmpe_gpio *stmpe_gpio = gpiochip_get_data(gc);
+	int i;
+
+	if (!stmpe_gpio->norequest_mask)
+		return;
+
+	/* Forbid unused lines to be mapped as IRQs */
+	for (i = 0; i < sizeof(u32); i++) {
+		if (stmpe_gpio->norequest_mask & BIT(i))
+			clear_bit(i, valid_mask);
+	}
+}
+
 static int stmpe_gpio_probe(struct platform_device *pdev)
 {
 	struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
@@ -454,14 +471,21 @@ static int stmpe_gpio_probe(struct platform_device *pdev)
 	stmpe_gpio->chip.parent = &pdev->dev;
 	stmpe_gpio->chip.of_node = np;
 	stmpe_gpio->chip.base = -1;
+	/*
+	 * REVISIT: this makes sure the valid mask gets allocated and
+	 * filled in when adding the gpio_chip, but the rest of the
+	 * gpio_irqchip is still filled in using the old method
+	 * in gpiochip_irqchip_add_nested() so clean this up once we
+	 * get the gpio_irqchip to initialize while adding the
+	 * gpio_chip also for threaded irqchips.
+	 */
+	stmpe_gpio->chip.irq.init_valid_mask = stmpe_init_irq_valid_mask;
 
 	if (IS_ENABLED(CONFIG_DEBUG_FS))
                 stmpe_gpio->chip.dbg_show = stmpe_dbg_show;
 
 	of_property_read_u32(np, "st,norequest-mask",
 			&stmpe_gpio->norequest_mask);
-	if (stmpe_gpio->norequest_mask)
-		stmpe_gpio->chip.irq.need_valid_mask = true;
 
 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0)
@@ -487,14 +511,6 @@ static int stmpe_gpio_probe(struct platform_device *pdev)
 			dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
 			goto out_disable;
 		}
-		if (stmpe_gpio->norequest_mask) {
-			int i;
-
-			/* Forbid unused lines to be mapped as IRQs */
-			for (i = 0; i < sizeof(u32); i++)
-				if (stmpe_gpio->norequest_mask & BIT(i))
-					clear_bit(i, stmpe_gpio->chip.irq.valid_mask);
-		}
 		ret =  gpiochip_irqchip_add_nested(&stmpe_gpio->chip,
 						   &stmpe_gpio_irq_chip,
 						   0,

drivers/gpio/gpio-tqmx86.c

@@ -214,6 +214,17 @@ static const struct dev_pm_ops tqmx86_gpio_dev_pm_ops = {
 			   tqmx86_gpio_runtime_resume, NULL)
 };
 
+static void tqmx86_init_irq_valid_mask(struct gpio_chip *chip,
+				       unsigned long *valid_mask,
+				       unsigned int ngpios)
+{
+	/* Only GPIOs 4-7 are valid for interrupts. Clear the others */
+	clear_bit(0, valid_mask);
+	clear_bit(1, valid_mask);
+	clear_bit(2, valid_mask);
+	clear_bit(3, valid_mask);
+}
+
 static int tqmx86_gpio_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -260,7 +271,6 @@ static int tqmx86_gpio_probe(struct platform_device *pdev)
 	chip->get = tqmx86_gpio_get;
 	chip->set = tqmx86_gpio_set;
 	chip->ngpio = TQMX86_NGPIO;
-	chip->irq.need_valid_mask = true;
 	chip->parent = pdev->dev.parent;
 
 	pm_runtime_enable(&pdev->dev);
@@ -296,6 +306,7 @@ static int tqmx86_gpio_probe(struct platform_device *pdev)
 		girq->parents[0] = irq;
 		girq->default_type = IRQ_TYPE_NONE;
 		girq->handler = handle_simple_irq;
+		girq->init_valid_mask = tqmx86_init_irq_valid_mask;
 	}
 
 	ret = devm_gpiochip_add_data(dev, chip, gpio);
@@ -304,14 +315,6 @@ static int tqmx86_gpio_probe(struct platform_device *pdev)
 		goto out_pm_dis;
 	}
 
-	/* Only GPIOs 4-7 are valid for interrupts. Clear the others */
-	if (irq) {
-		clear_bit(0, girq->valid_mask);
-		clear_bit(1, girq->valid_mask);
-		clear_bit(2, girq->valid_mask);
-		clear_bit(3, girq->valid_mask);
-	}
-
 	dev_info(dev, "GPIO functionality initialized with %d pins\n",
 		 chip->ngpio);
 

drivers/gpio/gpiolib.c

@@ -1615,15 +1615,19 @@ static struct gpio_chip *find_chip_by_name(const char *name)
  * The following is irqchip helper code for gpiochips.
  */
 
-static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip)
+static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc)
 {
-	if (!gpiochip->irq.need_valid_mask)
+	struct gpio_irq_chip *girq = &gc->irq;
+
+	if (!girq->init_valid_mask)
 		return 0;
 
-	gpiochip->irq.valid_mask = gpiochip_allocate_mask(gpiochip);
-	if (!gpiochip->irq.valid_mask)
+	girq->valid_mask = gpiochip_allocate_mask(gc);
+	if (!girq->valid_mask)
 		return -ENOMEM;
 
+	girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio);
+
 	return 0;
 }
 

drivers/pinctrl/intel/pinctrl-baytrail.c

@@ -1455,6 +1455,20 @@ static void byt_gpio_irq_handler(struct irq_desc *desc)
 	chip->irq_eoi(data);
 }
 
+static void byt_init_irq_valid_mask(struct gpio_chip *chip,
+				    unsigned long *valid_mask,
+				    unsigned int ngpios)
+{
+	/*
+	 * FIXME: currently the valid_mask is filled in as part of
+	 * initializing the irq_chip below in byt_gpio_irq_init_hw().
+	 * when converting this driver to the new way of passing the
+	 * gpio_irq_chip along when adding the gpio_chip, move the
+	 * mask initialization into this callback instead. Right now
+	 * this callback is here to make sure the mask gets allocated.
+	 */
+}
+
 static void byt_gpio_irq_init_hw(struct byt_gpio *vg)
 {
 	struct gpio_chip *gc = &vg->chip;
@@ -1525,7 +1539,7 @@ static int byt_gpio_probe(struct byt_gpio *vg)
 	gc->can_sleep	= false;
 	gc->parent	= &vg->pdev->dev;
 	gc->ngpio	= vg->soc_data->npins;
-	gc->irq.need_valid_mask	= true;
+	gc->irq.init_valid_mask	= byt_init_irq_valid_mask;
 
 #ifdef CONFIG_PM_SLEEP
 	vg->saved_context = devm_kcalloc(&vg->pdev->dev, gc->ngpio,

drivers/pinctrl/intel/pinctrl-cherryview.c

@@ -1543,6 +1543,30 @@ static const struct dmi_system_id chv_no_valid_mask[] = {
 	{}
 };
 
+static void chv_init_irq_valid_mask(struct gpio_chip *chip,
+				    unsigned long *valid_mask,
+				    unsigned int ngpios)
+{
+	struct chv_pinctrl *pctrl = gpiochip_get_data(chip);
+	const struct chv_community *community = pctrl->community;
+	int i;
+
+	/* Do not add GPIOs that can only generate GPEs to the IRQ domain */
+	for (i = 0; i < community->npins; i++) {
+		const struct pinctrl_pin_desc *desc;
+		u32 intsel;
+
+		desc = &community->pins[i];
+
+		intsel = readl(chv_padreg(pctrl, desc->number, CHV_PADCTRL0));
+		intsel &= CHV_PADCTRL0_INTSEL_MASK;
+		intsel >>= CHV_PADCTRL0_INTSEL_SHIFT;
+
+		if (intsel >= community->nirqs)
+			clear_bit(i, valid_mask);
+	}
+}
+
 static int chv_gpio_probe(struct chv_pinctrl *pctrl, int irq)
 {
 	const struct chv_gpio_pinrange *range;
@@ -1557,7 +1581,8 @@ static int chv_gpio_probe(struct chv_pinctrl *pctrl, int irq)
 	chip->label = dev_name(pctrl->dev);
 	chip->parent = pctrl->dev;
 	chip->base = -1;
-	chip->irq.need_valid_mask = need_valid_mask;
+	if (need_valid_mask)
+		chip->irq.init_valid_mask = chv_init_irq_valid_mask;
 
 	ret = devm_gpiochip_add_data(pctrl->dev, chip, pctrl);
 	if (ret) {
@@ -1576,21 +1601,6 @@ static int chv_gpio_probe(struct chv_pinctrl *pctrl, int irq)
 		}
 	}
 
-	/* Do not add GPIOs that can only generate GPEs to the IRQ domain */
-	for (i = 0; i < community->npins; i++) {
-		const struct pinctrl_pin_desc *desc;
-		u32 intsel;
-
-		desc = &community->pins[i];
-
-		intsel = readl(chv_padreg(pctrl, desc->number, CHV_PADCTRL0));
-		intsel &= CHV_PADCTRL0_INTSEL_MASK;
-		intsel >>= CHV_PADCTRL0_INTSEL_SHIFT;
-
-		if (need_valid_mask && intsel >= community->nirqs)
-			clear_bit(i, chip->irq.valid_mask);
-	}
-
 	/*
 	 * The same set of machines in chv_no_valid_mask[] have incorrectly
 	 * configured GPIOs that generate spurious interrupts so we use

drivers/platform/x86/intel_int0002_vgpio.c

@@ -152,6 +152,13 @@ static const struct x86_cpu_id int0002_cpu_ids[] = {
 	{}
 };
 
+static void int0002_init_irq_valid_mask(struct gpio_chip *chip,
+					unsigned long *valid_mask,
+					unsigned int ngpios)
+{
+	bitmap_clear(valid_mask, 0, GPE0A_PME_B0_VIRT_GPIO_PIN);
+}
+
 static int int0002_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
@@ -184,7 +191,7 @@ static int int0002_probe(struct platform_device *pdev)
 	chip->direction_output = int0002_gpio_direction_output;
 	chip->base = -1;
 	chip->ngpio = GPE0A_PME_B0_VIRT_GPIO_PIN + 1;
-	chip->irq.need_valid_mask = true;
+	chip->irq.init_valid_mask = int0002_init_irq_valid_mask;
 
 	ret = devm_gpiochip_add_data(&pdev->dev, chip, NULL);
 	if (ret) {
@@ -192,8 +199,6 @@ static int int0002_probe(struct platform_device *pdev)
 		return ret;
 	}
 
-	bitmap_clear(chip->irq.valid_mask, 0, GPE0A_PME_B0_VIRT_GPIO_PIN);
-
 	/*
 	 * We manually request the irq here instead of passing a flow-handler
 	 * to gpiochip_set_chained_irqchip, because the irq is shared.

include/linux/gpio/driver.h

@@ -202,11 +202,17 @@ struct gpio_irq_chip {
 	bool threaded;
 
 	/**
-	 * @need_valid_mask:
-	 *
-	 * If set core allocates @valid_mask with all bits set to one.
+	 * @init_valid_mask: optional routine to initialize @valid_mask, to be
+	 * used if not all GPIO lines are valid interrupts. Sometimes some
+	 * lines just cannot fire interrupts, and this routine, when defined,
+	 * is passed a bitmap in "valid_mask" and it will have ngpios
+	 * bits from 0..(ngpios-1) set to "1" as in valid. The callback can
+	 * then directly set some bits to "0" if they cannot be used for
+	 * interrupts.
 	 */
-	bool need_valid_mask;
+	void (*init_valid_mask)(struct gpio_chip *chip,
+				unsigned long *valid_mask,
+				unsigned int ngpios);
 
 	/**
 	 * @valid_mask: