mfd: twl6040: Add initial support

TWL6040 IC provides analog high-end audio codec functions for
handset applications. It contains several audio analog inputs
and outputs as well as vibrator support. It's connected to the
host processor via PDM interface for audio data communication.
The audio modules are controlled by internal registers that
can be accessed by I2C and PDM interface.

TWL6040 MFD will be registered as a child of TWL-CORE, and will
have two children of its own: twl6040-codec and twl6040-vibra.

This driver is based on TWL4030 and WM8350 MFD drivers.

Signed-off-by: Misael Lopez Cruz <misael.lopez@ti.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 205 insertions, 0 deletions

diff --git a/drivers/mfd/twl6040-irq.c b/drivers/mfd/twl6040-irq.c
new file mode 100644
index 000000000000..938053541520
--- /dev/null
+++ b/drivers/mfd/twl6040-irq.c
@@ -0,0 +1,205 @@
+/*
+ * Interrupt controller support for TWL6040
+ *
+ * Author:     Misael Lopez Cruz <misael.lopez@ti.com>
+ *
+ * Copyright:   (C) 2011 Texas Instruments, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/twl6040.h>
+
+struct twl6040_irq_data {
+	int mask;
+	int status;
+};
+
+static struct twl6040_irq_data twl6040_irqs[] = {
+	{
+		.mask = TWL6040_THMSK,
+		.status = TWL6040_THINT,
+	},
+	{
+		.mask = TWL6040_PLUGMSK,
+		.status = TWL6040_PLUGINT | TWL6040_UNPLUGINT,
+	},
+	{
+		.mask = TWL6040_HOOKMSK,
+		.status = TWL6040_HOOKINT,
+	},
+	{
+		.mask = TWL6040_HFMSK,
+		.status = TWL6040_HFINT,
+	},
+	{
+		.mask = TWL6040_VIBMSK,
+		.status = TWL6040_VIBINT,
+	},
+	{
+		.mask = TWL6040_READYMSK,
+		.status = TWL6040_READYINT,
+	},
+};
+
+static inline
+struct twl6040_irq_data *irq_to_twl6040_irq(struct twl6040 *twl6040,
+					    int irq)
+{
+	return &twl6040_irqs[irq - twl6040->irq_base];
+}
+
+static void twl6040_irq_lock(struct irq_data *data)
+{
+	struct twl6040 *twl6040 = irq_data_get_irq_chip_data(data);
+
+	mutex_lock(&twl6040->irq_mutex);
+}
+
+static void twl6040_irq_sync_unlock(struct irq_data *data)
+{
+	struct twl6040 *twl6040 = irq_data_get_irq_chip_data(data);
+
+	/* write back to hardware any change in irq mask */
+	if (twl6040->irq_masks_cur != twl6040->irq_masks_cache) {
+		twl6040->irq_masks_cache = twl6040->irq_masks_cur;
+		twl6040_reg_write(twl6040, TWL6040_REG_INTMR,
+				  twl6040->irq_masks_cur);
+	}
+
+	mutex_unlock(&twl6040->irq_mutex);
+}
+
+static void twl6040_irq_enable(struct irq_data *data)
+{
+	struct twl6040 *twl6040 = irq_data_get_irq_chip_data(data);
+	struct twl6040_irq_data *irq_data = irq_to_twl6040_irq(twl6040,
+							       data->irq);
+
+	twl6040->irq_masks_cur &= ~irq_data->mask;
+}
+
+static void twl6040_irq_disable(struct irq_data *data)
+{
+	struct twl6040 *twl6040 = irq_data_get_irq_chip_data(data);
+	struct twl6040_irq_data *irq_data = irq_to_twl6040_irq(twl6040,
+							       data->irq);
+
+	twl6040->irq_masks_cur |= irq_data->mask;
+}
+
+static struct irq_chip twl6040_irq_chip = {
+	.name			= "twl6040",
+	.irq_bus_lock		= twl6040_irq_lock,
+	.irq_bus_sync_unlock	= twl6040_irq_sync_unlock,
+	.irq_enable		= twl6040_irq_enable,
+	.irq_disable		= twl6040_irq_disable,
+};
+
+static irqreturn_t twl6040_irq_thread(int irq, void *data)
+{
+	struct twl6040 *twl6040 = data;
+	u8 intid;
+	int i;
+
+	intid = twl6040_reg_read(twl6040, TWL6040_REG_INTID);
+
+	/* apply masking and report (backwards to handle READYINT first) */
+	for (i = ARRAY_SIZE(twl6040_irqs) - 1; i >= 0; i--) {
+		if (twl6040->irq_masks_cur & twl6040_irqs[i].mask)
+			intid &= ~twl6040_irqs[i].status;
+		if (intid & twl6040_irqs[i].status)
+			handle_nested_irq(twl6040->irq_base + i);
+	}
+
+	/* ack unmasked irqs */
+	twl6040_reg_write(twl6040, TWL6040_REG_INTID, intid);
+
+	return IRQ_HANDLED;
+}
+
+int twl6040_irq_init(struct twl6040 *twl6040)
+{
+	int cur_irq, ret;
+	u8 val;
+
+	mutex_init(&twl6040->irq_mutex);
+
+	/* mask the individual interrupt sources */
+	twl6040->irq_masks_cur = TWL6040_ALLINT_MSK;
+	twl6040->irq_masks_cache = TWL6040_ALLINT_MSK;
+	twl6040_reg_write(twl6040, TWL6040_REG_INTMR, TWL6040_ALLINT_MSK);
+
+	if (!twl6040->irq) {
+		dev_warn(twl6040->dev,
+			 "no interrupt specified, no interrupts\n");
+		twl6040->irq_base = 0;
+		return 0;
+	}
+
+	if (!twl6040->irq_base) {
+		dev_err(twl6040->dev,
+			"no interrupt base specified, no interrupts\n");
+		return 0;
+	}
+
+	/* Register them with genirq */
+	for (cur_irq = twl6040->irq_base;
+	     cur_irq < twl6040->irq_base + ARRAY_SIZE(twl6040_irqs);
+	     cur_irq++) {
+		irq_set_chip_data(cur_irq, twl6040);
+		irq_set_chip_and_handler(cur_irq, &twl6040_irq_chip,
+					 handle_level_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
+		irq_set_noprobe(cur_irq);
+#endif
+	}
+
+	ret = request_threaded_irq(twl6040->irq, NULL, twl6040_irq_thread,
+				   IRQF_ONESHOT, "twl6040", twl6040);
+	if (ret) {
+		dev_err(twl6040->dev, "failed to request IRQ %d: %d\n",
+			twl6040->irq, ret);
+		return ret;
+	}
+
+	/* reset interrupts */
+	val = twl6040_reg_read(twl6040, TWL6040_REG_INTID);
+
+	/* interrupts cleared on write */
+	twl6040_clear_bits(twl6040, TWL6040_REG_ACCCTL, TWL6040_INTCLRMODE);
+
+	return 0;
+}
+EXPORT_SYMBOL(twl6040_irq_init);
+
+void twl6040_irq_exit(struct twl6040 *twl6040)
+{
+	if (twl6040->irq)
+		free_irq(twl6040->irq, twl6040);
+}
+EXPORT_SYMBOL(twl6040_irq_exit);