mfd: Add WM8994 interrupt controller support

The WM8994 has an interrupt controller which supports interrupts for
both CODEC and GPIO portions of the chip. Support this using genirq,
while allowing for systems that do not have an interrupt hooked up.

Wrapper functions are provided for the IRQ request and free to simplify
the code in consumer drivers when handling cases where IRQs are not
set up.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/mfd/Kconfig

@@ -301,9 +301,9 @@ config MFD_WM8350_I2C
 	  selected to enable support for the functionality of the chip.
 
 config MFD_WM8994
-	tristate "Support Wolfson Microelectronics WM8994"
+	bool "Support Wolfson Microelectronics WM8994"
 	select MFD_CORE
-	depends on I2C
+	depends on I2C=y && GENERIC_HARDIRQS
 	help
 	  The WM8994 is a highly integrated hi-fi CODEC designed for
 	  smartphone applicatiosn.  As well as audio functionality it

drivers/mfd/Makefile

@@ -26,7 +26,7 @@ wm8350-objs			:= wm8350-core.o wm8350-regmap.o wm8350-gpio.o
 wm8350-objs			+= wm8350-irq.o
 obj-$(CONFIG_MFD_WM8350)	+= wm8350.o
 obj-$(CONFIG_MFD_WM8350_I2C)	+= wm8350-i2c.o
-obj-$(CONFIG_MFD_WM8994)	+= wm8994-core.o
+obj-$(CONFIG_MFD_WM8994)	+= wm8994-core.o wm8994-irq.o
 
 obj-$(CONFIG_TPS65010)		+= tps65010.o
 obj-$(CONFIG_MENELAUS)		+= menelaus.o

drivers/mfd/wm8994-core.c

@@ -172,9 +172,34 @@ static struct mfd_cell wm8994_regulator_devs[] = {
 	{ .name = "wm8994-ldo", .id = 2 },
 };
 
+static struct resource wm8994_codec_resources[] = {
+	{
+		.start = WM8994_IRQ_TEMP_SHUT,
+		.end   = WM8994_IRQ_TEMP_WARN,
+		.flags = IORESOURCE_IRQ,
+	},
+};
+
+static struct resource wm8994_gpio_resources[] = {
+	{
+		.start = WM8994_IRQ_GPIO(1),
+		.end   = WM8994_IRQ_GPIO(11),
+		.flags = IORESOURCE_IRQ,
+	},
+};
+
 static struct mfd_cell wm8994_devs[] = {
-	{ .name = "wm8994-codec" },
-	{ .name = "wm8994-gpio" },
+	{
+		.name = "wm8994-codec",
+		.num_resources = ARRAY_SIZE(wm8994_codec_resources),
+		.resources = wm8994_codec_resources,
+	},
+
+	{
+		.name = "wm8994-gpio",
+		.num_resources = ARRAY_SIZE(wm8994_gpio_resources),
+		.resources = wm8994_gpio_resources,
+	},
 };
 
 /*
@@ -235,6 +260,11 @@ static int wm8994_device_resume(struct device *dev)
 		return ret;
 	}
 
+	ret = wm8994_write(wm8994, WM8994_INTERRUPT_STATUS_1_MASK,
+			   WM8994_NUM_IRQ_REGS * 2, &wm8994->irq_masks_cur);
+	if (ret < 0)
+		dev_err(dev, "Failed to restore interrupt masks: %d\n", ret);
+
 	ret = wm8994_write(wm8994, WM8994_LDO_1, WM8994_NUM_LDO_REGS * 2,
 			   &wm8994->ldo_regs);
 	if (ret < 0)
@@ -347,6 +377,7 @@ static int wm8994_device_init(struct wm8994 *wm8994, unsigned long id, int irq)
 
 
 	if (pdata) {
+		wm8994->irq_base = pdata->irq_base;
 		wm8994->gpio_base = pdata->gpio_base;
 
 		/* GPIO configuration is only applied if it's non-zero */
@@ -374,16 +405,20 @@ static int wm8994_device_init(struct wm8994 *wm8994, unsigned long id, int irq)
 					WM8994_LDO1_DISCH, 0);
 	}
 
+	wm8994_irq_init(wm8994);
+
 	ret = mfd_add_devices(wm8994->dev, -1,
 			      wm8994_devs, ARRAY_SIZE(wm8994_devs),
 			      NULL, 0);
 	if (ret != 0) {
 		dev_err(wm8994->dev, "Failed to add children: %d\n", ret);
-		goto err_enable;
+		goto err_irq;
 	}
 
 	return 0;
 
+err_irq:
+	wm8994_irq_exit(wm8994);
 err_enable:
 	regulator_bulk_disable(ARRAY_SIZE(wm8994_main_supplies),
 			       wm8994->supplies);
@@ -400,6 +435,7 @@ static int wm8994_device_init(struct wm8994 *wm8994, unsigned long id, int irq)
 static void wm8994_device_exit(struct wm8994 *wm8994)
 {
 	mfd_remove_devices(wm8994->dev);
+	wm8994_irq_exit(wm8994);
 	regulator_bulk_disable(ARRAY_SIZE(wm8994_main_supplies),
 			       wm8994->supplies);
 	regulator_bulk_free(ARRAY_SIZE(wm8994_main_supplies), wm8994->supplies);
@@ -468,6 +504,7 @@ static int wm8994_i2c_probe(struct i2c_client *i2c,
 	wm8994->control_data = i2c;
 	wm8994->read_dev = wm8994_i2c_read_device;
 	wm8994->write_dev = wm8994_i2c_write_device;
+	wm8994->irq = i2c->irq;
 
 	return wm8994_device_init(wm8994, id->driver_data, i2c->irq);
 }