diff mbox series

[v2,5/8] drivers: pinctrl: msm: setup GPIO irqchip hierarchy

Message ID 20190124202205.7940-6-ilina@codeaurora.org (mailing list archive)
State Not Applicable, archived
Headers show
Series qcom: support wakeup capable GPIOs | expand

Commit Message

Lina Iyer Jan. 24, 2019, 8:22 p.m. UTC
To allow GPIOs to wakeup the system from suspend or deep idle, the
wakeup capable GPIOs are setup in hierarchy with interrupts from the
wakeup-parent irqchip.

In older SoC's, the TLMM will handover detection to the parent irqchip
and in newer SoC's, the parent irqchip may also be active as well as the
TLMM and therefore the GPIOs need to be masked at TLMM to avoid
duplicate interrupts. To enable both these configurations to exist,
allow the parent irqchip to dictate the TLMM irqchip's behavior when
masking/unmasking the interrupt.

Co-developed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Lina Iyer <ilina@codeaurora.org>

---
Changes in v2:
	- Fix bug when unmaksing PDC interrupt
---
 drivers/pinctrl/qcom/pinctrl-msm.c | 133 ++++++++++++++++++++++++++---
 1 file changed, 120 insertions(+), 13 deletions(-)

Comments

Stephen Boyd Jan. 30, 2019, 10:45 p.m. UTC | #1
Quoting Lina Iyer (2019-01-24 12:22:02)
> To allow GPIOs to wakeup the system from suspend or deep idle, the
> wakeup capable GPIOs are setup in hierarchy with interrupts from the
> wakeup-parent irqchip.
> 
> In older SoC's, the TLMM will handover detection to the parent irqchip
> and in newer SoC's, the parent irqchip may also be active as well as the
> TLMM and therefore the GPIOs need to be masked at TLMM to avoid
> duplicate interrupts. To enable both these configurations to exist,
> allow the parent irqchip to dictate the TLMM irqchip's behavior when
> masking/unmasking the interrupt.
> 
> Co-developed-by: Stephen Boyd <swboyd@chromium.org>
> Signed-off-by: Lina Iyer <ilina@codeaurora.org>
> 
> ---
> Changes in v2:
>         - Fix bug when unmaksing PDC interrupt

What was the bug? Is that why the mask callback in this gpio chip no
longer calls the parent irq chip? We should keep calling the parent
irqchip from what I can tell. Otherwise, we may never mask the irq at
the PDC and only mask it at the GPIO level, which may not even care
about it if it's being monitored by the PDC.

This causes me to get a bunch of interrupts on my touchscreen when I
touch it once vs. only a handful (like 4) when I fix it with the below
patch:

Can you fold it in?

diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
index dd72ec8fb8db..9b45219893bd 100644
--- a/drivers/pinctrl/qcom/pinctrl-msm.c
+++ b/drivers/pinctrl/qcom/pinctrl-msm.c
@@ -682,6 +682,9 @@ static void msm_gpio_irq_mask(struct irq_data *d)
 	clear_bit(d->hwirq, pctrl->enabled_irqs);
 
 	raw_spin_unlock_irqrestore(&pctrl->lock, flags);
+
+	if (d->parent_data)
+		irq_chip_mask_parent(d);
 }
 
 static void msm_gpio_irq_unmask(struct irq_data *d)
Lina Iyer Jan. 31, 2019, 4:34 p.m. UTC | #2
On Wed, Jan 30 2019 at 15:45 -0700, Stephen Boyd wrote:
>Quoting Lina Iyer (2019-01-24 12:22:02)
>> To allow GPIOs to wakeup the system from suspend or deep idle, the
>> wakeup capable GPIOs are setup in hierarchy with interrupts from the
>> wakeup-parent irqchip.
>>
>> In older SoC's, the TLMM will handover detection to the parent irqchip
>> and in newer SoC's, the parent irqchip may also be active as well as the
>> TLMM and therefore the GPIOs need to be masked at TLMM to avoid
>> duplicate interrupts. To enable both these configurations to exist,
>> allow the parent irqchip to dictate the TLMM irqchip's behavior when
>> masking/unmasking the interrupt.
>>
>> Co-developed-by: Stephen Boyd <swboyd@chromium.org>
>> Signed-off-by: Lina Iyer <ilina@codeaurora.org>
>>
>> ---
>> Changes in v2:
>>         - Fix bug when unmaksing PDC interrupt
>
>What was the bug? 
The problem was an incorrect merge (possibly manual), causing the PDC to
be not used at all. This is what I had -

 static void msm_gpio_irq_mask(struct irq_data *d)                                  
 {                                                                                  
         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);                      
         struct msm_pinctrl *pctrl = gpiochip_get_data(gc);                         
         const struct msm_pingroup *g;                                              
         unsigned long flags;                                                       
         u32 val;                                                                   
                                                                                    
         g = &pctrl->soc->groups[d->hwirq];                                         
                                                                                    
         if (d->parent_data)                                                        
                 irq_chip_unmask_parent(d);                                         
                                                                                    
         /* Monitored by parent wakeup controller? Keep masked */                   
         if (test_bit(d->hwirq, pctrl->wakeup_masked_irqs))                         
                 return;                                                            
                                                                                    

The above unmask_parent() call in an irq_mask() callback was the bug.

>Is that why the mask callback in this gpio chip no
>longer calls the parent irq chip? We should keep calling the parent
>irqchip from what I can tell. Otherwise, we may never mask the irq at
>the PDC and only mask it at the GPIO level, which may not even care
>about it if it's being monitored by the PDC.
>
>This causes me to get a bunch of interrupts on my touchscreen when I
>touch it once vs. only a handful (like 4) when I fix it with the below
>patch:
>
Hmm... I did not see an issue in my local testing :(
Thanks for the fix.

>Can you fold it in?
>
Yes, I will fold it in and send a rev out with the fix.

Thanks,
Lina

>diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
>index dd72ec8fb8db..9b45219893bd 100644
>--- a/drivers/pinctrl/qcom/pinctrl-msm.c
>+++ b/drivers/pinctrl/qcom/pinctrl-msm.c
>@@ -682,6 +682,9 @@ static void msm_gpio_irq_mask(struct irq_data *d)
> 	clear_bit(d->hwirq, pctrl->enabled_irqs);
>
> 	raw_spin_unlock_irqrestore(&pctrl->lock, flags);
>+
>+	if (d->parent_data)
>+		irq_chip_mask_parent(d);
> }
>
> static void msm_gpio_irq_unmask(struct irq_data *d)
diff mbox series

Patch

diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
index ee8119879c4c..e13bead566aa 100644
--- a/drivers/pinctrl/qcom/pinctrl-msm.c
+++ b/drivers/pinctrl/qcom/pinctrl-msm.c
@@ -17,6 +17,7 @@ 
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_irq.h>
 #include <linux/platform_device.h>
 #include <linux/pinctrl/machine.h>
 #include <linux/pinctrl/pinctrl.h>
@@ -27,6 +28,7 @@ 
 #include <linux/gpio/driver.h>
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
+#include <linux/soc/qcom/irq.h>
 #include <linux/reboot.h>
 #include <linux/pm.h>
 #include <linux/log2.h>
@@ -69,6 +71,7 @@  struct msm_pinctrl {
 
 	DECLARE_BITMAP(dual_edge_irqs, MAX_NR_GPIO);
 	DECLARE_BITMAP(enabled_irqs, MAX_NR_GPIO);
+	DECLARE_BITMAP(wakeup_masked_irqs, MAX_NR_GPIO);
 
 	const struct msm_pinctrl_soc_data *soc;
 	void __iomem *regs[MAX_NR_TILES];
@@ -747,6 +750,13 @@  static void msm_gpio_irq_unmask(struct irq_data *d)
 
 	g = &pctrl->soc->groups[d->hwirq];
 
+	if (d->parent_data)
+		irq_chip_unmask_parent(d);
+
+	/* Monitored by parent wakeup controller? Keep masked */
+	if (test_bit(d->hwirq, pctrl->wakeup_masked_irqs))
+		return;
+
 	raw_spin_lock_irqsave(&pctrl->lock, flags);
 
 	val = msm_readl_intr_cfg(pctrl, g);
@@ -767,6 +777,10 @@  static void msm_gpio_irq_ack(struct irq_data *d)
 	unsigned long flags;
 	u32 val;
 
+	/* Handled by parent wakeup controller? Do nothing */
+	if (test_bit(d->hwirq, pctrl->wakeup_masked_irqs))
+		return;
+
 	g = &pctrl->soc->groups[d->hwirq];
 
 	raw_spin_lock_irqsave(&pctrl->lock, flags);
@@ -794,6 +808,13 @@  static int msm_gpio_irq_set_type(struct irq_data *d, unsigned int type)
 
 	g = &pctrl->soc->groups[d->hwirq];
 
+	if (d->parent_data)
+		irq_chip_set_type_parent(d, type);
+
+	/* Monitored by parent wakeup controller? Keep masked */
+	if (test_bit(d->hwirq, pctrl->wakeup_masked_irqs))
+		return 0;
+
 	raw_spin_lock_irqsave(&pctrl->lock, flags);
 
 	/*
@@ -890,6 +911,9 @@  static int msm_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
 
 	raw_spin_unlock_irqrestore(&pctrl->lock, flags);
 
+	if (d->parent_data)
+		irq_chip_set_wake_parent(d, on);
+
 	return 0;
 }
 
@@ -967,11 +991,86 @@  static bool msm_gpio_needs_valid_mask(struct msm_pinctrl *pctrl)
 	return device_property_read_u16_array(pctrl->dev, "gpios", NULL, 0) > 0;
 }
 
+static int msm_gpio_domain_translate(struct irq_domain *d,
+				     struct irq_fwspec *fwspec,
+				     unsigned long *hwirq, unsigned int *type)
+{
+	if (is_of_node(fwspec->fwnode)) {
+		if (fwspec->param_count < 2)
+			return -EINVAL;
+		*hwirq = fwspec->param[0];
+		*type = fwspec->param[1] & IRQ_TYPE_SENSE_MASK;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int msm_gpio_domain_alloc(struct irq_domain *domain, unsigned int virq,
+				 unsigned int nr_irqs, void *arg)
+{
+	int ret;
+	irq_hw_number_t hwirq;
+	struct gpio_chip *gc = domain->host_data;
+	struct msm_pinctrl *pctrl = gpiochip_get_data(gc);
+	struct irq_fwspec *fwspec = arg;
+	struct qcom_irq_fwspec parent = { };
+	unsigned int type;
+
+	ret = msm_gpio_domain_translate(domain, fwspec, &hwirq, &type);
+	if (ret)
+		return ret;
+
+	ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
+					    &pctrl->irq_chip, gc);
+	if (ret < 0)
+		return ret;
+
+	if (!domain->parent)
+		return 0;
+
+	parent.fwspec.fwnode      = domain->parent->fwnode;
+	parent.fwspec.param_count = 2;
+	parent.fwspec.param[0]    = hwirq;
+	parent.fwspec.param[1]    = type;
+
+	ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &parent);
+	if (ret)
+		return ret;
+
+	if (parent.mask)
+		set_bit(hwirq, pctrl->wakeup_masked_irqs);
+
+	return 0;
+}
+
+/*
+ * TODO: Get rid of this and push it into gpiochip_to_irq()
+ */
+static int msm_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
+{
+	struct irq_fwspec fwspec;
+
+	fwspec.fwnode = of_node_to_fwnode(chip->of_node);
+	fwspec.param[0] = offset;
+	fwspec.param[1] = IRQ_TYPE_LEVEL_HIGH;
+	fwspec.param_count = 2;
+
+	return irq_create_fwspec_mapping(&fwspec);
+}
+
+static const struct irq_domain_ops msm_gpio_domain_ops = {
+	.translate = msm_gpio_domain_translate,
+	.alloc     = msm_gpio_domain_alloc,
+	.free      = irq_domain_free_irqs_top,
+};
+
 static int msm_gpio_init(struct msm_pinctrl *pctrl)
 {
 	struct gpio_chip *chip;
 	int ret;
 	unsigned ngpio = pctrl->soc->ngpios;
+	struct device_node *dn;
 
 	if (WARN_ON(ngpio > MAX_NR_GPIO))
 		return -EINVAL;
@@ -986,6 +1085,7 @@  static int msm_gpio_init(struct msm_pinctrl *pctrl)
 	chip->need_valid_mask = msm_gpio_needs_valid_mask(pctrl);
 
 	pctrl->irq_chip.name = "msmgpio";
+	pctrl->irq_chip.irq_eoi	= irq_chip_eoi_parent;
 	pctrl->irq_chip.irq_mask = msm_gpio_irq_mask;
 	pctrl->irq_chip.irq_unmask = msm_gpio_irq_unmask;
 	pctrl->irq_chip.irq_ack = msm_gpio_irq_ack;
@@ -994,6 +1094,22 @@  static int msm_gpio_init(struct msm_pinctrl *pctrl)
 	pctrl->irq_chip.irq_request_resources = msm_gpio_irq_reqres;
 	pctrl->irq_chip.irq_release_resources = msm_gpio_irq_relres;
 
+	chip->irq.chip = &pctrl->irq_chip;
+	chip->irq.domain_ops = &msm_gpio_domain_ops;
+	chip->irq.handler = handle_edge_irq;
+	chip->irq.default_type = IRQ_TYPE_NONE;
+
+	dn = of_parse_phandle(pctrl->dev->of_node, "wakeup-parent", 0);
+	if (dn) {
+		chip->irq.parent_domain = irq_find_matching_host(dn,
+						 DOMAIN_BUS_WAKEUP);
+		of_node_put(dn);
+		if (!chip->irq.parent_domain)
+			return -EPROBE_DEFER;
+
+		chip->to_irq = msm_gpio_to_irq;
+	}
+
 	ret = gpiochip_add_data(&pctrl->chip, pctrl);
 	if (ret) {
 		dev_err(pctrl->dev, "Failed register gpiochip\n");
@@ -1015,26 +1131,17 @@  static int msm_gpio_init(struct msm_pinctrl *pctrl)
 			dev_name(pctrl->dev), 0, 0, chip->ngpio);
 		if (ret) {
 			dev_err(pctrl->dev, "Failed to add pin range\n");
-			gpiochip_remove(&pctrl->chip);
-			return ret;
+			goto fail;
 		}
 	}
 
-	ret = gpiochip_irqchip_add(chip,
-				   &pctrl->irq_chip,
-				   0,
-				   handle_edge_irq,
-				   IRQ_TYPE_NONE);
-	if (ret) {
-		dev_err(pctrl->dev, "Failed to add irqchip to gpiochip\n");
-		gpiochip_remove(&pctrl->chip);
-		return -ENOSYS;
-	}
-
 	gpiochip_set_chained_irqchip(chip, &pctrl->irq_chip, pctrl->irq,
 				     msm_gpio_irq_handler);
 
 	return 0;
+fail:
+	gpiochip_remove(&pctrl->chip);
+	return ret;
 }
 
 static int msm_ps_hold_restart(struct notifier_block *nb, unsigned long action,