pinctrl: single: Add support for wake-up interrupts
The pin control registers can have interrupts for example
for device wake-up. These interrupts can be treated as a
chained interrupt controller as suggested earlier by
Linus Walleij <linus.walleij@linaro.org>.
This patch adds support for interrupts in a way that
should be pretty generic, and works for the omaps that
support wake-up interrupts. On omaps, there's an
interrupt enable and interrupt status bit for each pin.
The two pinctrl domains on omaps share a single interrupt
from the PRM chained interrupt handler. Support for
other similar hardware should be easy to add.
Note that this patch does not attempt to handle the
wake-up interrupts automatically unlike the earlier
patches. This patch allows the device drivers to do
a request_irq() on the wake-up pins as needed. I'll
try to do also a separate generic patch for handling
the wake-up events automatically.
Also note that as this patch makes the pinctrl-single
an irq controller, the current bindings need some
extra trickery to use interrupts from two different
interrupt controllers for the same driver. So it
might be worth waiting a little on the patches
enabling the wake-up interrupts from drivers as there
should be a generic way to handle it coming. And also
there's been discussion of interrupts-extended binding
for using interrupts from multiple interrupt controllers.
In any case, this patch should be ready to go allowing
handling the wake-up interrupts in a generic way, or
separately from the device drivers.
Cc: Peter Ujfalusi <peter.ujfalusi@ti.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Cc: Prakash Manjunathappa <prakash.pm@ti.com>
Cc: Roger Quadros <rogerq@ti.com>
Cc: linux-kernel@vger.kernel.org
Cc: Benoît Cousson <bcousson@baylibre.com>
Cc: devicetree@vger.kernel.org
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
index f88d3d1..dad65df 100644
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -15,10 +15,14 @@
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/list.h>
+#include <linux/interrupt.h>
+
+#include <linux/irqchip/chained_irq.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_address.h>
+#include <linux/of_irq.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>
@@ -152,9 +156,15 @@
/**
* struct pcs_soc_data - SoC specific settings
* @flags: initial SoC specific PCS_FEAT_xxx values
+ * @irq: optional interrupt for the controller
+ * @irq_enable_mask: optional SoC specific interrupt enable mask
+ * @irq_status_mask: optional SoC specific interrupt status mask
*/
struct pcs_soc_data {
unsigned flags;
+ int irq;
+ unsigned irq_enable_mask;
+ unsigned irq_status_mask;
};
/**
@@ -165,6 +175,7 @@
* @dev: device entry
* @pctl: pin controller device
* @flags: mask of PCS_FEAT_xxx values
+ * @lock: spinlock for register access
* @mutex: mutex protecting the lists
* @width: bits per mux register
* @fmask: function register mask
@@ -179,6 +190,9 @@
* @pingroups: list of pingroups
* @functions: list of functions
* @gpiofuncs: list of gpio functions
+ * @irqs: list of interrupt registers
+ * @chip: chip container for this instance
+ * @domain: IRQ domain for this instance
* @ngroups: number of pingroups
* @nfuncs: number of functions
* @desc: pin controller descriptor
@@ -192,7 +206,11 @@
struct device *dev;
struct pinctrl_dev *pctl;
unsigned flags;
+#define PCS_QUIRK_SHARED_IRQ (1 << 2)
+#define PCS_FEAT_IRQ (1 << 1)
#define PCS_FEAT_PINCONF (1 << 0)
+ struct pcs_soc_data socdata;
+ raw_spinlock_t lock;
struct mutex mutex;
unsigned width;
unsigned fmask;
@@ -208,6 +226,9 @@
struct list_head pingroups;
struct list_head functions;
struct list_head gpiofuncs;
+ struct list_head irqs;
+ struct irq_chip chip;
+ struct irq_domain *domain;
unsigned ngroups;
unsigned nfuncs;
struct pinctrl_desc desc;
@@ -215,6 +236,8 @@
void (*write)(unsigned val, void __iomem *reg);
};
+#define PCS_QUIRK_HAS_SHARED_IRQ (pcs->flags & PCS_QUIRK_SHARED_IRQ)
+#define PCS_HAS_IRQ (pcs->flags & PCS_FEAT_IRQ)
#define PCS_HAS_PINCONF (pcs->flags & PCS_FEAT_PINCONF)
static int pcs_pinconf_get(struct pinctrl_dev *pctldev, unsigned pin,
@@ -440,9 +463,11 @@
for (i = 0; i < func->nvals; i++) {
struct pcs_func_vals *vals;
+ unsigned long flags;
unsigned val, mask;
vals = &func->vals[i];
+ raw_spin_lock_irqsave(&pcs->lock, flags);
val = pcs->read(vals->reg);
if (pcs->bits_per_mux)
@@ -453,6 +478,7 @@
val &= ~mask;
val |= (vals->val & mask);
pcs->write(val, vals->reg);
+ raw_spin_unlock_irqrestore(&pcs->lock, flags);
}
return 0;
@@ -494,13 +520,16 @@
for (i = 0; i < func->nvals; i++) {
struct pcs_func_vals *vals;
+ unsigned long flags;
unsigned val;
vals = &func->vals[i];
+ raw_spin_lock_irqsave(&pcs->lock, flags);
val = pcs->read(vals->reg);
val &= ~pcs->fmask;
val |= pcs->foff << pcs->fshift;
pcs->write(val, vals->reg);
+ raw_spin_unlock_irqrestore(&pcs->lock, flags);
}
}
@@ -1451,11 +1480,33 @@
}
/**
+ * pcs_irq_free() - free interrupt
+ * @pcs: pcs driver instance
+ */
+static void pcs_irq_free(struct pcs_device *pcs)
+{
+ struct pcs_soc_data *pcs_soc = &pcs->socdata;
+
+ if (pcs_soc->irq < 0)
+ return;
+
+ if (pcs->domain)
+ irq_domain_remove(pcs->domain);
+
+ if (PCS_QUIRK_HAS_SHARED_IRQ)
+ free_irq(pcs_soc->irq, pcs_soc);
+ else
+ irq_set_chained_handler(pcs_soc->irq, NULL);
+}
+
+/**
* pcs_free_resources() - free memory used by this driver
* @pcs: pcs driver instance
*/
static void pcs_free_resources(struct pcs_device *pcs)
{
+ pcs_irq_free(pcs);
+
if (pcs->pctl)
pinctrl_unregister(pcs->pctl);
@@ -1504,6 +1555,256 @@
}
return ret;
}
+/**
+ * @reg: virtual address of interrupt register
+ * @hwirq: hardware irq number
+ * @irq: virtual irq number
+ * @node: list node
+ */
+struct pcs_interrupt {
+ void __iomem *reg;
+ irq_hw_number_t hwirq;
+ unsigned int irq;
+ struct list_head node;
+};
+
+/**
+ * pcs_irq_set() - enables or disables an interrupt
+ *
+ * Note that this currently assumes one interrupt per pinctrl
+ * register that is typically used for wake-up events.
+ */
+static inline void pcs_irq_set(struct pcs_soc_data *pcs_soc,
+ int irq, const bool enable)
+{
+ struct pcs_device *pcs;
+ struct list_head *pos;
+ unsigned mask;
+
+ pcs = container_of(pcs_soc, struct pcs_device, socdata);
+ list_for_each(pos, &pcs->irqs) {
+ struct pcs_interrupt *pcswi;
+ unsigned soc_mask;
+
+ pcswi = list_entry(pos, struct pcs_interrupt, node);
+ if (irq != pcswi->irq)
+ continue;
+
+ soc_mask = pcs_soc->irq_enable_mask;
+ raw_spin_lock(&pcs->lock);
+ mask = pcs->read(pcswi->reg);
+ if (enable)
+ mask |= soc_mask;
+ else
+ mask &= ~soc_mask;
+ pcs->write(mask, pcswi->reg);
+ raw_spin_unlock(&pcs->lock);
+ }
+}
+
+/**
+ * pcs_irq_mask() - mask pinctrl interrupt
+ * @d: interrupt data
+ */
+static void pcs_irq_mask(struct irq_data *d)
+{
+ struct pcs_soc_data *pcs_soc = irq_data_get_irq_chip_data(d);
+
+ pcs_irq_set(pcs_soc, d->irq, false);
+}
+
+/**
+ * pcs_irq_unmask() - unmask pinctrl interrupt
+ * @d: interrupt data
+ */
+static void pcs_irq_unmask(struct irq_data *d)
+{
+ struct pcs_soc_data *pcs_soc = irq_data_get_irq_chip_data(d);
+
+ pcs_irq_set(pcs_soc, d->irq, true);
+}
+
+/**
+ * pcs_irq_set_wake() - toggle the suspend and resume wake up
+ * @d: interrupt data
+ * @state: wake-up state
+ *
+ * Note that this should be called only for suspend and resume.
+ * For runtime PM, the wake-up events should be enabled by default.
+ */
+static int pcs_irq_set_wake(struct irq_data *d, unsigned int state)
+{
+ if (state)
+ pcs_irq_unmask(d);
+ else
+ pcs_irq_mask(d);
+
+ return 0;
+}
+
+/**
+ * pcs_irq_handle() - common interrupt handler
+ * @pcs_irq: interrupt data
+ *
+ * Note that this currently assumes we have one interrupt bit per
+ * mux register. This interrupt is typically used for wake-up events.
+ * For more complex interrupts different handlers can be specified.
+ */
+static int pcs_irq_handle(struct pcs_soc_data *pcs_soc)
+{
+ struct pcs_device *pcs;
+ struct list_head *pos;
+ int count = 0;
+
+ pcs = container_of(pcs_soc, struct pcs_device, socdata);
+ list_for_each(pos, &pcs->irqs) {
+ struct pcs_interrupt *pcswi;
+ unsigned mask;
+
+ pcswi = list_entry(pos, struct pcs_interrupt, node);
+ raw_spin_lock(&pcs->lock);
+ mask = pcs->read(pcswi->reg);
+ raw_spin_unlock(&pcs->lock);
+ if (mask & pcs_soc->irq_status_mask) {
+ generic_handle_irq(irq_find_mapping(pcs->domain,
+ pcswi->hwirq));
+ count++;
+ }
+ }
+
+ return count;
+}
+
+/**
+ * pcs_irq_handler() - handler for the shared interrupt case
+ * @irq: interrupt
+ * @d: data
+ *
+ * Use this for cases where multiple instances of
+ * pinctrl-single share a single interrupt like on omaps.
+ */
+static irqreturn_t pcs_irq_handler(int irq, void *d)
+{
+ struct pcs_soc_data *pcs_soc = d;
+
+ return pcs_irq_handle(pcs_soc) ? IRQ_HANDLED : IRQ_NONE;
+}
+
+/**
+ * pcs_irq_handle() - handler for the dedicated chained interrupt case
+ * @irq: interrupt
+ * @desc: interrupt descriptor
+ *
+ * Use this if you have a separate interrupt for each
+ * pinctrl-single instance.
+ */
+static void pcs_irq_chain_handler(unsigned int irq, struct irq_desc *desc)
+{
+ struct pcs_soc_data *pcs_soc = irq_desc_get_handler_data(desc);
+ struct irq_chip *chip;
+ int res;
+
+ chip = irq_get_chip(irq);
+ chained_irq_enter(chip, desc);
+ res = pcs_irq_handle(pcs_soc);
+ /* REVISIT: export and add handle_bad_irq(irq, desc)? */
+ chained_irq_exit(chip, desc);
+
+ return;
+}
+
+static int pcs_irqdomain_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hwirq)
+{
+ struct pcs_soc_data *pcs_soc = d->host_data;
+ struct pcs_device *pcs;
+ struct pcs_interrupt *pcswi;
+
+ pcs = container_of(pcs_soc, struct pcs_device, socdata);
+ pcswi = devm_kzalloc(pcs->dev, sizeof(*pcswi), GFP_KERNEL);
+ if (!pcswi)
+ return -ENOMEM;
+
+ pcswi->reg = pcs->base + hwirq;
+ pcswi->hwirq = hwirq;
+ pcswi->irq = irq;
+
+ mutex_lock(&pcs->mutex);
+ list_add_tail(&pcswi->node, &pcs->irqs);
+ mutex_unlock(&pcs->mutex);
+
+ irq_set_chip_data(irq, pcs_soc);
+ irq_set_chip_and_handler(irq, &pcs->chip,
+ handle_level_irq);
+ set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+
+ return 0;
+}
+
+static struct irq_domain_ops pcs_irqdomain_ops = {
+ .map = pcs_irqdomain_map,
+ .xlate = irq_domain_xlate_onecell,
+};
+
+/**
+ * pcs_irq_init_chained_handler() - set up a chained interrupt handler
+ * @pcs: pcs driver instance
+ * @np: device node pointer
+ */
+static int pcs_irq_init_chained_handler(struct pcs_device *pcs,
+ struct device_node *np)
+{
+ struct pcs_soc_data *pcs_soc = &pcs->socdata;
+ const char *name = "pinctrl";
+ int num_irqs;
+
+ if (!pcs_soc->irq_enable_mask ||
+ !pcs_soc->irq_status_mask) {
+ pcs_soc->irq = -1;
+ return -EINVAL;
+ }
+
+ INIT_LIST_HEAD(&pcs->irqs);
+ pcs->chip.name = name;
+ pcs->chip.irq_ack = pcs_irq_mask;
+ pcs->chip.irq_mask = pcs_irq_mask;
+ pcs->chip.irq_unmask = pcs_irq_unmask;
+ pcs->chip.irq_set_wake = pcs_irq_set_wake;
+
+ if (PCS_QUIRK_HAS_SHARED_IRQ) {
+ int res;
+
+ res = request_irq(pcs_soc->irq, pcs_irq_handler,
+ IRQF_SHARED | IRQF_NO_SUSPEND,
+ name, pcs_soc);
+ if (res) {
+ pcs_soc->irq = -1;
+ return res;
+ }
+ } else {
+ irq_set_handler_data(pcs_soc->irq, pcs_soc);
+ irq_set_chained_handler(pcs_soc->irq,
+ pcs_irq_chain_handler);
+ }
+
+ /*
+ * We can use the register offset as the hardirq
+ * number as irq_domain_add_simple maps them lazily.
+ * This way we can easily support more than one
+ * interrupt per function if needed.
+ */
+ num_irqs = pcs->size;
+
+ pcs->domain = irq_domain_add_simple(np, num_irqs, 0,
+ &pcs_irqdomain_ops,
+ pcs_soc);
+ if (!pcs->domain) {
+ irq_set_chained_handler(pcs_soc->irq, NULL);
+ return -EINVAL;
+ }
+
+ return 0;
+}
#ifdef CONFIG_PM
static int pinctrl_single_suspend(struct platform_device *pdev,
@@ -1549,12 +1850,14 @@
return -ENOMEM;
}
pcs->dev = &pdev->dev;
+ raw_spin_lock_init(&pcs->lock);
mutex_init(&pcs->mutex);
INIT_LIST_HEAD(&pcs->pingroups);
INIT_LIST_HEAD(&pcs->functions);
INIT_LIST_HEAD(&pcs->gpiofuncs);
soc = match->data;
pcs->flags = soc->flags;
+ memcpy(&pcs->socdata, soc, sizeof(*soc));
PCS_GET_PROP_U32("pinctrl-single,register-width", &pcs->width,
"register width not specified\n");
@@ -1642,6 +1945,16 @@
if (ret < 0)
goto free;
+ pcs->socdata.irq = irq_of_parse_and_map(np, 0);
+ if (pcs->socdata.irq)
+ pcs->flags |= PCS_FEAT_IRQ;
+
+ if (PCS_HAS_IRQ) {
+ ret = pcs_irq_init_chained_handler(pcs, np);
+ if (ret < 0)
+ dev_warn(pcs->dev, "initialized with no interrupts\n");
+ }
+
dev_info(pcs->dev, "%i pins at pa %p size %u\n",
pcs->desc.npins, pcs->base, pcs->size);
@@ -1665,6 +1978,12 @@
return 0;
}
+static const struct pcs_soc_data pinctrl_single_omap_wkup = {
+ .flags = PCS_QUIRK_SHARED_IRQ,
+ .irq_enable_mask = (1 << 14), /* OMAP_WAKEUP_EN */
+ .irq_status_mask = (1 << 15), /* OMAP_WAKEUP_EVENT */
+};
+
static const struct pcs_soc_data pinctrl_single = {
};
@@ -1673,6 +1992,9 @@
};
static struct of_device_id pcs_of_match[] = {
+ { .compatible = "ti,omap3-padconf", .data = &pinctrl_single_omap_wkup },
+ { .compatible = "ti,omap4-padconf", .data = &pinctrl_single_omap_wkup },
+ { .compatible = "ti,omap5-padconf", .data = &pinctrl_single_omap_wkup },
{ .compatible = "pinctrl-single", .data = &pinctrl_single },
{ .compatible = "pinconf-single", .data = &pinconf_single },
{ },