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author | Tony Lindgren | 2013-10-03 06:39:40 +0200 |
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committer | Tony Lindgren | 2013-10-11 00:30:30 +0200 |
commit | 3e6cee1786a13cb2308609b5f8c020e1754e37cf (patch) | |
tree | f76f85def8d2fd5654146ff9e612371590555573 /drivers/pinctrl/pinctrl-single.c | |
parent | pinctrl: single: Prepare for supporting SoC specific features (diff) | |
download | kernel-qcow2-linux-3e6cee1786a13cb2308609b5f8c020e1754e37cf.tar.gz kernel-qcow2-linux-3e6cee1786a13cb2308609b5f8c020e1754e37cf.tar.xz kernel-qcow2-linux-3e6cee1786a13cb2308609b5f8c020e1754e37cf.zip |
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: BenoƮt 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>
Diffstat (limited to 'drivers/pinctrl/pinctrl-single.c')
-rw-r--r-- | drivers/pinctrl/pinctrl-single.c | 322 |
1 files changed, 322 insertions, 0 deletions
diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c index f88d3d1b2b99..dad65df36f4b 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_name { /** * 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 @@ struct pcs_soc_data { * @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 @@ struct pcs_soc_data { * @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 pcs_device { 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 pcs_device { 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 @@ struct pcs_device { 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 @@ static int pcs_enable(struct pinctrl_dev *pctldev, unsigned fselector, 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 @@ static int pcs_enable(struct pinctrl_dev *pctldev, unsigned fselector, val &= ~mask; val |= (vals->val & mask); pcs->write(val, vals->reg); + raw_spin_unlock_irqrestore(&pcs->lock, flags); } return 0; @@ -494,13 +520,16 @@ static void pcs_disable(struct pinctrl_dev *pctldev, unsigned fselector, 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 @@ static void pcs_free_pingroups(struct pcs_device *pcs) } /** + * 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 @@ static int pcs_add_gpio_func(struct device_node *node, struct pcs_device *pcs) } 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 @@ static int pcs_probe(struct platform_device *pdev) 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 @@ static int pcs_probe(struct platform_device *pdev) 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 @@ static int pcs_remove(struct platform_device *pdev) 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 const struct pcs_soc_data pinconf_single = { }; 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 }, { }, |