mfd: Add MAX8998 interrupts support

Use genirq and provide seperated file for interrupts support.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/drivers/mfd/max8998-irq.c b/drivers/mfd/max8998-irq.c
new file mode 100644
index 0000000..346fd29
--- /dev/null
+++ b/drivers/mfd/max8998-irq.c
@@ -0,0 +1,255 @@
+/*
+ * Interrupt controller support for MAX8998
+ *
+ * Copyright (C) 2010 Samsung Electronics Co.Ltd
+ * Author: Joonyoung Shim <jy0922.shim@samsung.com>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/mfd/max8998-private.h>
+
+struct max8998_irq_data {
+	int reg;
+	int mask;
+};
+
+static struct max8998_irq_data max8998_irqs[] = {
+	[MAX8998_IRQ_DCINF] = {
+		.reg = 1,
+		.mask = MAX8998_IRQ_DCINF_MASK,
+	},
+	[MAX8998_IRQ_DCINR] = {
+		.reg = 1,
+		.mask = MAX8998_IRQ_DCINR_MASK,
+	},
+	[MAX8998_IRQ_JIGF] = {
+		.reg = 1,
+		.mask = MAX8998_IRQ_JIGF_MASK,
+	},
+	[MAX8998_IRQ_JIGR] = {
+		.reg = 1,
+		.mask = MAX8998_IRQ_JIGR_MASK,
+	},
+	[MAX8998_IRQ_PWRONF] = {
+		.reg = 1,
+		.mask = MAX8998_IRQ_PWRONF_MASK,
+	},
+	[MAX8998_IRQ_PWRONR] = {
+		.reg = 1,
+		.mask = MAX8998_IRQ_PWRONR_MASK,
+	},
+	[MAX8998_IRQ_WTSREVNT] = {
+		.reg = 2,
+		.mask = MAX8998_IRQ_WTSREVNT_MASK,
+	},
+	[MAX8998_IRQ_SMPLEVNT] = {
+		.reg = 2,
+		.mask = MAX8998_IRQ_SMPLEVNT_MASK,
+	},
+	[MAX8998_IRQ_ALARM1] = {
+		.reg = 2,
+		.mask = MAX8998_IRQ_ALARM1_MASK,
+	},
+	[MAX8998_IRQ_ALARM0] = {
+		.reg = 2,
+		.mask = MAX8998_IRQ_ALARM0_MASK,
+	},
+	[MAX8998_IRQ_ONKEY1S] = {
+		.reg = 3,
+		.mask = MAX8998_IRQ_ONKEY1S_MASK,
+	},
+	[MAX8998_IRQ_TOPOFFR] = {
+		.reg = 3,
+		.mask = MAX8998_IRQ_TOPOFFR_MASK,
+	},
+	[MAX8998_IRQ_DCINOVPR] = {
+		.reg = 3,
+		.mask = MAX8998_IRQ_DCINOVPR_MASK,
+	},
+	[MAX8998_IRQ_CHGRSTF] = {
+		.reg = 3,
+		.mask = MAX8998_IRQ_CHGRSTF_MASK,
+	},
+	[MAX8998_IRQ_DONER] = {
+		.reg = 3,
+		.mask = MAX8998_IRQ_DONER_MASK,
+	},
+	[MAX8998_IRQ_CHGFAULT] = {
+		.reg = 3,
+		.mask = MAX8998_IRQ_CHGFAULT_MASK,
+	},
+	[MAX8998_IRQ_LOBAT1] = {
+		.reg = 4,
+		.mask = MAX8998_IRQ_LOBAT1_MASK,
+	},
+	[MAX8998_IRQ_LOBAT2] = {
+		.reg = 4,
+		.mask = MAX8998_IRQ_LOBAT2_MASK,
+	},
+};
+
+static inline struct max8998_irq_data *
+irq_to_max8998_irq(struct max8998_dev *max8998, int irq)
+{
+	return &max8998_irqs[irq - max8998->irq_base];
+}
+
+static void max8998_irq_lock(unsigned int irq)
+{
+	struct max8998_dev *max8998 = get_irq_chip_data(irq);
+
+	mutex_lock(&max8998->irqlock);
+}
+
+static void max8998_irq_sync_unlock(unsigned int irq)
+{
+	struct max8998_dev *max8998 = get_irq_chip_data(irq);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(max8998->irq_masks_cur); i++) {
+		/*
+		 * If there's been a change in the mask write it back
+		 * to the hardware.
+		 */
+		if (max8998->irq_masks_cur[i] != max8998->irq_masks_cache[i]) {
+			max8998->irq_masks_cache[i] = max8998->irq_masks_cur[i];
+			max8998_write_reg(max8998->i2c, MAX8998_REG_IRQM1 + i,
+					max8998->irq_masks_cur[i]);
+		}
+	}
+
+	mutex_unlock(&max8998->irqlock);
+}
+
+static void max8998_irq_unmask(unsigned int irq)
+{
+	struct max8998_dev *max8998 = get_irq_chip_data(irq);
+	struct max8998_irq_data *irq_data = irq_to_max8998_irq(max8998, irq);
+
+	max8998->irq_masks_cur[irq_data->reg - 1] &= ~irq_data->mask;
+}
+
+static void max8998_irq_mask(unsigned int irq)
+{
+	struct max8998_dev *max8998 = get_irq_chip_data(irq);
+	struct max8998_irq_data *irq_data = irq_to_max8998_irq(max8998, irq);
+
+	max8998->irq_masks_cur[irq_data->reg - 1] |= irq_data->mask;
+}
+
+static struct irq_chip max8998_irq_chip = {
+	.name = "max8998",
+	.bus_lock = max8998_irq_lock,
+	.bus_sync_unlock = max8998_irq_sync_unlock,
+	.mask = max8998_irq_mask,
+	.unmask = max8998_irq_unmask,
+};
+
+static irqreturn_t max8998_irq_thread(int irq, void *data)
+{
+	struct max8998_dev *max8998 = data;
+	u8 irq_reg[MAX8998_NUM_IRQ_REGS];
+	int ret;
+	int i;
+
+	ret = max8998_bulk_read(max8998->i2c, MAX8998_REG_IRQ1,
+			MAX8998_NUM_IRQ_REGS, irq_reg);
+	if (ret < 0) {
+		dev_err(max8998->dev, "Failed to read interrupt register: %d\n",
+				ret);
+		return IRQ_NONE;
+	}
+
+	/* Apply masking */
+	for (i = 0; i < MAX8998_NUM_IRQ_REGS; i++)
+		irq_reg[i] &= ~max8998->irq_masks_cur[i];
+
+	/* Report */
+	for (i = 0; i < MAX8998_IRQ_NR; i++) {
+		if (irq_reg[max8998_irqs[i].reg - 1] & max8998_irqs[i].mask)
+			handle_nested_irq(max8998->irq_base + i);
+	}
+
+	return IRQ_HANDLED;
+}
+
+int max8998_irq_init(struct max8998_dev *max8998)
+{
+	int i;
+	int cur_irq;
+	int ret;
+
+	if (!max8998->irq) {
+		dev_warn(max8998->dev,
+			 "No interrupt specified, no interrupts\n");
+		max8998->irq_base = 0;
+		return 0;
+	}
+
+	if (!max8998->irq_base) {
+		dev_err(max8998->dev,
+			"No interrupt base specified, no interrupts\n");
+		return 0;
+	}
+
+	mutex_init(&max8998->irqlock);
+
+	/* Mask the individual interrupt sources */
+	for (i = 0; i < MAX8998_NUM_IRQ_REGS; i++) {
+		max8998->irq_masks_cur[i] = 0xff;
+		max8998->irq_masks_cache[i] = 0xff;
+		max8998_write_reg(max8998->i2c, MAX8998_REG_IRQM1 + i, 0xff);
+	}
+
+	max8998_write_reg(max8998->i2c, MAX8998_REG_STATUSM1, 0xff);
+	max8998_write_reg(max8998->i2c, MAX8998_REG_STATUSM2, 0xff);
+
+	/* register with genirq */
+	for (i = 0; i < MAX8998_IRQ_NR; i++) {
+		cur_irq = i + max8998->irq_base;
+		set_irq_chip_data(cur_irq, max8998);
+		set_irq_chip_and_handler(cur_irq, &max8998_irq_chip,
+					 handle_edge_irq);
+		set_irq_nested_thread(cur_irq, 1);
+#ifdef CONFIG_ARM
+		set_irq_flags(cur_irq, IRQF_VALID);
+#else
+		set_irq_noprobe(cur_irq);
+#endif
+	}
+
+	ret = request_threaded_irq(max8998->irq, NULL, max8998_irq_thread,
+				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+				   "max8998-irq", max8998);
+	if (ret) {
+		dev_err(max8998->dev, "Failed to request IRQ %d: %d\n",
+			max8998->irq, ret);
+		return ret;
+	}
+
+	if (!max8998->ono)
+		return 0;
+
+	ret = request_threaded_irq(max8998->ono, NULL, max8998_irq_thread,
+				   IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING |
+				   IRQF_ONESHOT, "max8998-ono", max8998);
+	if (ret)
+		dev_err(max8998->dev, "Failed to request IRQ %d: %d\n",
+			max8998->ono, ret);
+
+	return 0;
+}
+
+void max8998_irq_exit(struct max8998_dev *max8998)
+{
+	if (max8998->irq)
+		free_irq(max8998->irq, max8998);
+}