[PATCH v9 4/4] mfd: ac200: Add codec and TV encoder cells

[James Hilliard <james.hilliard1@gmail.com>]

From: Jernej Skrabec <jernej.skrabec@gmail.com>

Register the AC200 audio codec and TV encoder as MFD cells when their
enabled child nodes are present. Filtering the cell list avoids creating
unused platform devices, or warnings about missing firmware nodes, on
boards which use only the separately enumerated MDIO PHY.

Add a regmap IRQ controller for the shared level-triggered INTB output so
the TV encoder can consume its cable-detection interrupt. The source
function remains responsible for clearing its interrupt condition.

Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: James Hilliard <james.hilliard1@gmail.com>
---
 drivers/mfd/Kconfig |   5 ++-
 drivers/mfd/ac200.c | 119 +++++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 122 insertions(+), 2 deletions(-)

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 6dea35c8c18e..5193c6f71bd8 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -210,12 +210,15 @@ config MFD_AC200
 	depends on COMMON_CLK
 	depends on I2C
 	depends on OF
+	select MFD_CORE
 	select REGMAP_I2C
+	select REGMAP_IRQ
 	help
 	  Support for the X-Powers AC200 mixed-signal companion IC. The AC200
 	  contains audio, video, RTC and Fast Ethernet PHY functions and is
 	  co-packaged with some Allwinner H6 and H616 SoCs. This driver provides
-	  the shared register access used by the individual function drivers.
+	  the shared register access and instantiates the individual function
+	  devices.
 
 config MFD_AXP20X
 	tristate
diff --git a/drivers/mfd/ac200.c b/drivers/mfd/ac200.c
index 94aa13deb0f8..f7d818141d9c 100644
--- a/drivers/mfd/ac200.c
+++ b/drivers/mfd/ac200.c
@@ -9,11 +9,24 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/mfd/core.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/regmap.h>
 
+#include <dt-bindings/mfd/x-powers,ac200.h>
+
 #define AC200_SYS_CONTROL_REG			0x0002
 #define AC200_SYS_CONTROL_CHIP_RESET_DEASSERT	BIT(0)
+#define AC200_SYS_IRQ_ENABLE_REG		0x0004
+#define AC200_SYS_IRQ_INTB_ENABLE		BIT(15)
+#define AC200_SYS_IRQ_INTB_ACTIVE_HIGH		BIT(14)
+#define AC200_SYS_IRQ_RTC			BIT(12)
+#define AC200_SYS_IRQ_EPHY			BIT(8)
+#define AC200_SYS_IRQ_TVE			BIT(4)
+#define AC200_SYS_IRQ_STATUS_REG		0x0006
 
 /* Interface register accessible from every register page. */
 #define AC200_TWI_REG_ADDR_H	0x00fe
@@ -51,6 +64,103 @@ static const struct regmap_config ac200_regmap_config = {
 	.cache_type = REGCACHE_MAPLE,
 };
 
+static const struct regmap_irq ac200_irqs[] = {
+	REGMAP_IRQ_REG(AC200_IRQ_TVE, 0, AC200_SYS_IRQ_TVE),
+	REGMAP_IRQ_REG(AC200_IRQ_EPHY, 0, AC200_SYS_IRQ_EPHY),
+	REGMAP_IRQ_REG(AC200_IRQ_RTC, 0, AC200_SYS_IRQ_RTC),
+};
+
+/*
+ * SYS_IRQ_ENABLE is an enable register rather than a mask register, hence
+ * unmask_base. SYS_IRQ_STATUS reflects the source levels, so the function
+ * which raised an interrupt is responsible for clearing it.
+ */
+static const struct regmap_irq_chip ac200_irq_chip = {
+	.name = "ac200",
+	.status_base = AC200_SYS_IRQ_STATUS_REG,
+	.unmask_base = AC200_SYS_IRQ_ENABLE_REG,
+	.num_regs = 1,
+	.irqs = ac200_irqs,
+	.num_irqs = ARRAY_SIZE(ac200_irqs),
+};
+
+static const struct mfd_cell ac200_cells[] = {
+	{
+		.name = "ac200-codec",
+		.of_compatible = "x-powers,ac200-codec",
+	}, {
+		.name = "ac200-tve",
+		.of_compatible = "x-powers,ac200-tve",
+	},
+};
+
+static int ac200_init_irq(struct device *dev, struct regmap *regmap, int irq)
+{
+	struct regmap_irq_chip_data *irq_data;
+	unsigned int trigger;
+	u16 value = AC200_SYS_IRQ_INTB_ENABLE;
+	int ret;
+
+	trigger = irq_get_trigger_type(irq);
+	switch (trigger) {
+	case IRQ_TYPE_LEVEL_HIGH:
+		value |= AC200_SYS_IRQ_INTB_ACTIVE_HIGH;
+		break;
+	case IRQ_TYPE_NONE:
+	case IRQ_TYPE_LEVEL_LOW:
+		break;
+	default:
+		return dev_err_probe(dev, -EINVAL,
+				     "INTB is level triggered, not type %u\n",
+				     trigger);
+	}
+
+	ret = regmap_update_bits(regmap, AC200_SYS_IRQ_ENABLE_REG,
+				 AC200_SYS_IRQ_INTB_ENABLE |
+				 AC200_SYS_IRQ_INTB_ACTIVE_HIGH, value);
+	if (ret)
+		return ret;
+
+	ret = devm_regmap_add_irq_chip(dev, regmap, irq, IRQF_ONESHOT, 0,
+				       &ac200_irq_chip, &irq_data);
+	if (ret)
+		return dev_err_probe(dev, ret, "failed to add IRQ chip\n");
+
+	return 0;
+}
+
+static int ac200_add_devices(struct device *dev)
+{
+	struct mfd_cell cells[ARRAY_SIZE(ac200_cells)];
+	unsigned int num_cells = 0;
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < ARRAY_SIZE(ac200_cells); i++) {
+		const struct mfd_cell *cell = &ac200_cells[i];
+		struct device_node *child;
+
+		child = of_get_compatible_child(dev->of_node,
+						cell->of_compatible);
+		if (!child)
+			continue;
+		if (of_device_is_available(child))
+			cells[num_cells++] = *cell;
+		of_node_put(child);
+	}
+
+	if (!num_cells)
+		return 0;
+
+	ret = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE, cells, num_cells,
+				   NULL, 0, NULL);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "failed to add function devices\n");
+
+	return 0;
+}
+
 static int ac200_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
@@ -83,7 +193,13 @@ static int ac200_probe(struct i2c_client *client)
 	if (ret)
 		return ret;
 
-	return 0;
+	if (client->irq > 0) {
+		ret = ac200_init_irq(dev, regmap, client->irq);
+		if (ret)
+			return ret;
+	}
+
+	return ac200_add_devices(dev);
 }
 
 static const struct of_device_id ac200_of_match[] = {
@@ -108,6 +224,7 @@ static struct i2c_driver ac200_driver = {
 };
 module_i2c_driver(ac200_driver);
 
+MODULE_AUTHOR("Jernej Skrabec <jernej.skrabec@gmail.com>");
 MODULE_AUTHOR("James Hilliard <james.hilliard1@gmail.com>");
 MODULE_DESCRIPTION("X-Powers AC200 MFD core driver");
 MODULE_LICENSE("GPL");

-- 
2.53.0