Initial Contribution

msm-2.6.38: tag AU_LINUX_ANDROID_GINGERBREAD.02.03.04.00.142

Signed-off-by: Bryan Huntsman <bryanh@codeaurora.org>
diff --git a/drivers/mfd/wcd9310-irq.c b/drivers/mfd/wcd9310-irq.c
new file mode 100644
index 0000000..bc7841e
--- /dev/null
+++ b/drivers/mfd/wcd9310-irq.c
@@ -0,0 +1,197 @@
+/* Copyright (c) 2011, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+#include <linux/bitops.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/irq.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/wcd9310/core.h>
+#include <linux/mfd/wcd9310/registers.h>
+#include <linux/interrupt.h>
+
+#define BYTE_BIT_MASK(nr)		(1UL << ((nr) % BITS_PER_BYTE))
+#define BIT_BYTE(nr)			((nr) / BITS_PER_BYTE)
+
+struct tabla_irq {
+	bool level;
+};
+
+static struct tabla_irq tabla_irqs[TABLA_NUM_IRQS] = {
+	[0] = { .level = 1},
+/* All other tabla interrupts are edge triggered */
+};
+
+static inline int irq_to_tabla_irq(struct tabla *tabla, int irq)
+{
+	return irq - tabla->irq_base;
+}
+
+static void tabla_irq_lock(struct irq_data *data)
+{
+	struct tabla *tabla = irq_data_get_irq_chip_data(data);
+	mutex_lock(&tabla->irq_lock);
+}
+
+static void tabla_irq_sync_unlock(struct irq_data *data)
+{
+	struct tabla *tabla = irq_data_get_irq_chip_data(data);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(tabla->irq_masks_cur); i++) {
+		/* If there's been a change in the mask write it back
+		 * to the hardware.
+		 */
+		if (tabla->irq_masks_cur[i] != tabla->irq_masks_cache[i]) {
+			tabla->irq_masks_cache[i] = tabla->irq_masks_cur[i];
+			tabla_reg_write(tabla, TABLA_A_INTR_MASK0+i,
+				tabla->irq_masks_cur[i]);
+		}
+	}
+
+	mutex_unlock(&tabla->irq_lock);
+}
+
+static void tabla_irq_enable(struct irq_data *data)
+{
+	struct tabla *tabla = irq_data_get_irq_chip_data(data);
+	int tabla_irq = irq_to_tabla_irq(tabla, data->irq);
+	tabla->irq_masks_cur[BIT_BYTE(tabla_irq)] &=
+		~(BYTE_BIT_MASK(tabla_irq));
+}
+
+static void tabla_irq_disable(struct irq_data *data)
+{
+	struct tabla *tabla = irq_data_get_irq_chip_data(data);
+	int tabla_irq = irq_to_tabla_irq(tabla, data->irq);
+	tabla->irq_masks_cur[BIT_BYTE(tabla_irq)] |= BYTE_BIT_MASK(tabla_irq);
+}
+
+static struct irq_chip tabla_irq_chip = {
+	.name = "tabla",
+	.irq_bus_lock = tabla_irq_lock,
+	.irq_bus_sync_unlock = tabla_irq_sync_unlock,
+	.irq_disable = tabla_irq_disable,
+	.irq_enable = tabla_irq_enable,
+};
+
+static irqreturn_t tabla_irq_thread(int irq, void *data)
+{
+	int ret;
+	struct tabla *tabla = data;
+	u8 status[TABLA_NUM_IRQ_REGS];
+	unsigned int i;
+
+	ret = tabla_bulk_read(tabla, TABLA_A_INTR_STATUS0,
+			       TABLA_NUM_IRQ_REGS, status);
+	if (ret < 0) {
+		dev_err(tabla->dev, "Failed to read interrupt status: %d\n",
+			ret);
+		return IRQ_NONE;
+	}
+	/* Apply masking */
+	for (i = 0; i < TABLA_NUM_IRQ_REGS; i++)
+		status[i] &= ~tabla->irq_masks_cur[i];
+
+	/* Find out which interrupt was triggered and call that interrupt's
+	 * handler function
+	 */
+	for (i = 0; i < TABLA_NUM_IRQS; i++) {
+		if (status[BIT_BYTE(i)] & BYTE_BIT_MASK(i)) {
+			if ((i <= TABLA_IRQ_MBHC_INSERTION) &&
+				(i >= TABLA_IRQ_MBHC_REMOVAL)) {
+				tabla_reg_write(tabla, TABLA_A_INTR_CLEAR0 +
+					BIT_BYTE(i), BYTE_BIT_MASK(i));
+				handle_nested_irq(tabla->irq_base + i);
+			} else {
+				handle_nested_irq(tabla->irq_base + i);
+				tabla_reg_write(tabla, TABLA_A_INTR_CLEAR0 +
+					BIT_BYTE(i), BYTE_BIT_MASK(i));
+			}
+			break;
+		}
+	}
+
+	return IRQ_HANDLED;
+}
+
+int tabla_irq_init(struct tabla *tabla)
+{
+	int ret;
+	unsigned int i, cur_irq;
+
+	mutex_init(&tabla->irq_lock);
+
+	if (!tabla->irq) {
+		dev_warn(tabla->dev,
+			 "No interrupt specified, no interrupts\n");
+		tabla->irq_base = 0;
+		return 0;
+	}
+
+	if (!tabla->irq_base) {
+		dev_err(tabla->dev,
+			"No interrupt base specified, no interrupts\n");
+		return 0;
+	}
+	/* Mask the individual interrupt sources */
+	for (i = 0, cur_irq = tabla->irq_base; i < TABLA_NUM_IRQS; i++,
+		cur_irq++) {
+
+		irq_set_chip_data(cur_irq, tabla);
+
+		if (tabla_irqs[i].level)
+			irq_set_chip_and_handler(cur_irq, &tabla_irq_chip,
+					 handle_level_irq);
+		else
+			irq_set_chip_and_handler(cur_irq, &tabla_irq_chip,
+					 handle_edge_irq);
+
+		irq_set_nested_thread(cur_irq, 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(cur_irq, IRQF_VALID);
+#else
+		set_irq_noprobe(cur_irq);
+#endif
+
+		tabla->irq_masks_cur[BIT_BYTE(i)] |= BYTE_BIT_MASK(i);
+		tabla->irq_masks_cache[BIT_BYTE(i)] |= BYTE_BIT_MASK(i);
+		tabla->irq_level[BIT_BYTE(i)] |= tabla_irqs[i].level <<
+			(i % BITS_PER_BYTE);
+	}
+	for (i = 0; i < TABLA_NUM_IRQ_REGS; i++) {
+		/* Initialize interrupt mask and level registers */
+		tabla_reg_write(tabla, TABLA_A_INTR_LEVEL0 + i,
+			tabla->irq_level[i]);
+		tabla_reg_write(tabla, TABLA_A_INTR_MASK0 + i,
+			tabla->irq_masks_cur[i]);
+	}
+
+	ret = request_threaded_irq(tabla->irq, NULL, tabla_irq_thread,
+				   IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
+				   "tabla", tabla);
+
+	if (ret != 0) {
+		dev_err(tabla->dev, "Failed to request IRQ %d: %d\n",
+			tabla->irq, ret);
+		return ret;
+	}
+	return 0;
+}
+void tabla_irq_exit(struct tabla *tabla)
+{
+	if (tabla->irq)
+		free_irq(tabla->irq, tabla);
+	mutex_destroy(&tabla->irq_lock);
+}