From 1e04de3425e9ef5450182c0da4cf18095ca26548 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Mon, 6 May 2013 16:12:56 +0100 Subject: [PATCH] mfd: wm8994: Emulate level triggered interrupts if required The interrupt controller on the wm8994 series of devices requires a level triggered parent. If one is not available but a GPIO is available for the interrupt then emulate. Signed-off-by: Mark Brown Signed-off-by: Samuel Ortiz --- drivers/mfd/wm8994-irq.c | 100 +++++++++++++++++++++++++++++-- include/linux/mfd/wm8994/core.h | 2 + include/linux/mfd/wm8994/pdata.h | 5 ++ 3 files changed, 103 insertions(+), 4 deletions(-) diff --git a/drivers/mfd/wm8994-irq.c b/drivers/mfd/wm8994-irq.c index a050e56a9bbd..d3a184a240f5 100644 --- a/drivers/mfd/wm8994-irq.c +++ b/drivers/mfd/wm8994-irq.c @@ -14,10 +14,12 @@ #include #include +#include #include #include #include #include +#include #include #include @@ -138,6 +140,55 @@ static struct regmap_irq_chip wm8994_irq_chip = { .runtime_pm = true, }; +static void wm8994_edge_irq_enable(struct irq_data *data) +{ +} + +static void wm8994_edge_irq_disable(struct irq_data *data) +{ +} + +static struct irq_chip wm8994_edge_irq_chip = { + .name = "wm8994_edge", + .irq_disable = wm8994_edge_irq_disable, + .irq_enable = wm8994_edge_irq_enable, +}; + +static irqreturn_t wm8994_edge_irq(int irq, void *data) +{ + struct wm8994 *wm8994 = data; + + while (gpio_get_value_cansleep(wm8994->pdata.irq_gpio)) + handle_nested_irq(irq_create_mapping(wm8994->edge_irq, 0)); + + return IRQ_HANDLED; +} + +static int wm8994_edge_irq_map(struct irq_domain *h, unsigned int virq, + irq_hw_number_t hw) +{ + struct wm8994 *wm8994 = h->host_data; + + irq_set_chip_data(virq, wm8994); + irq_set_chip_and_handler(virq, &wm8994_edge_irq_chip, handle_edge_irq); + irq_set_nested_thread(virq, 1); + + /* ARM needs us to explicitly flag the IRQ as valid + * and will set them noprobe when we do so. */ +#ifdef CONFIG_ARM + set_irq_flags(virq, IRQF_VALID); +#else + irq_set_noprobe(virq); +#endif + + return 0; +} + +static struct irq_domain_ops wm8994_edge_irq_ops = { + .map = wm8994_edge_irq_map, + .xlate = irq_domain_xlate_twocell, +}; + int wm8994_irq_init(struct wm8994 *wm8994) { int ret; @@ -156,10 +207,51 @@ int wm8994_irq_init(struct wm8994 *wm8994) if (pdata->irq_flags) irqflags = pdata->irq_flags; - ret = regmap_add_irq_chip(wm8994->regmap, wm8994->irq, - irqflags, - wm8994->irq_base, &wm8994_irq_chip, - &wm8994->irq_data); + /* use a GPIO for edge triggered controllers */ + if (irqflags & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)) { + if (gpio_to_irq(pdata->irq_gpio) != wm8994->irq) { + dev_warn(wm8994->dev, "IRQ %d is not GPIO %d (%d)\n", + wm8994->irq, pdata->irq_gpio, + gpio_to_irq(pdata->irq_gpio)); + wm8994->irq = gpio_to_irq(pdata->irq_gpio); + } + + ret = devm_gpio_request_one(wm8994->dev, pdata->irq_gpio, + GPIOF_IN, "WM8994 IRQ"); + + if (ret != 0) { + dev_err(wm8994->dev, "Failed to get IRQ GPIO: %d\n", + ret); + return ret; + } + + wm8994->edge_irq = irq_domain_add_linear(NULL, 1, + &wm8994_edge_irq_ops, + wm8994); + + ret = regmap_add_irq_chip(wm8994->regmap, + irq_create_mapping(wm8994->edge_irq, + 0), + IRQF_ONESHOT, + wm8994->irq_base, &wm8994_irq_chip, + &wm8994->irq_data); + if (ret != 0) { + dev_err(wm8994->dev, "Failed to get IRQ: %d\n", + ret); + return ret; + } + + ret = request_threaded_irq(wm8994->irq, + NULL, wm8994_edge_irq, + irqflags, + "WM8994 edge", wm8994); + } else { + ret = regmap_add_irq_chip(wm8994->regmap, wm8994->irq, + irqflags, + wm8994->irq_base, &wm8994_irq_chip, + &wm8994->irq_data); + } + if (ret != 0) { dev_err(wm8994->dev, "Failed to register IRQ chip: %d\n", ret); return ret; diff --git a/include/linux/mfd/wm8994/core.h b/include/linux/mfd/wm8994/core.h index ae5c249530b4..40854ac0ba3d 100644 --- a/include/linux/mfd/wm8994/core.h +++ b/include/linux/mfd/wm8994/core.h @@ -29,6 +29,7 @@ enum wm8994_type { struct regulator_dev; struct regulator_bulk_data; +struct irq_domain; #define WM8994_NUM_GPIO_REGS 11 #define WM8994_NUM_LDO_REGS 2 @@ -73,6 +74,7 @@ struct wm8994 { int irq; struct regmap_irq_chip_data *irq_data; + struct irq_domain *edge_irq; /* Used over suspend/resume */ bool suspended; diff --git a/include/linux/mfd/wm8994/pdata.h b/include/linux/mfd/wm8994/pdata.h index 68e776594889..90e9bf86e643 100644 --- a/include/linux/mfd/wm8994/pdata.h +++ b/include/linux/mfd/wm8994/pdata.h @@ -223,6 +223,11 @@ struct wm8994_pdata { * lines is mastered. */ int max_channels_clocked[WM8994_NUM_AIF]; + + /** + * GPIO for the IRQ pin if host only supports edge triggering + */ + int irq_gpio; }; #endif -- 2.39.5