1 files changed, 131 insertions, 211 deletions

diff --git a/drivers/mfd/twl4030-irq.c b/drivers/mfd/twl4030-irq.c
index 8a7ee3139b86..f062c8cc6c38 100644
--- a/drivers/mfd/twl4030-irq.c
+++ b/drivers/mfd/twl4030-irq.c
@@ -30,7 +30,6 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
-#include <linux/kthread.h>
 #include <linux/slab.h>
 
 #include <linux/i2c/twl.h>
@@ -278,59 +277,6 @@ static const struct sih sih_modules_twl5031[8] = {
 
 static unsigned twl4030_irq_base;
 
-static struct completion irq_event;
-
-/*
- * This thread processes interrupts reported by the Primary Interrupt Handler.
- */
-static int twl4030_irq_thread(void *data)
-{
-	long irq = (long)data;
-	static unsigned i2c_errors;
-	static const unsigned max_i2c_errors = 100;
-
-
-	current->flags |= PF_NOFREEZE;
-
-	while (!kthread_should_stop()) {
-		int ret;
-		int module_irq;
-		u8 pih_isr;
-
-		/* Wait for IRQ, then read PIH irq status (also blocking) */
-		wait_for_completion_interruptible(&irq_event);
-
-		ret = twl_i2c_read_u8(TWL4030_MODULE_PIH, &pih_isr,
-					  REG_PIH_ISR_P1);
-		if (ret) {
-			pr_warning("twl4030: I2C error %d reading PIH ISR\n",
-					ret);
-			if (++i2c_errors >= max_i2c_errors) {
-				printk(KERN_ERR "Maximum I2C error count"
-						" exceeded.  Terminating %s.\n",
-						__func__);
-				break;
-			}
-			complete(&irq_event);
-			continue;
-		}
-
-		/* these handlers deal with the relevant SIH irq status */
-		local_irq_disable();
-		for (module_irq = twl4030_irq_base;
-				pih_isr;
-				pih_isr >>= 1, module_irq++) {
-			if (pih_isr & 0x1)
-				generic_handle_irq(module_irq);
-		}
-		local_irq_enable();
-
-		enable_irq(irq);
-	}
-
-	return 0;
-}
-
 /*
  * handle_twl4030_pih() is the desc->handle method for the twl4030 interrupt.
  * This is a chained interrupt, so there is no desc->action method for it.
@@ -342,9 +288,25 @@ static int twl4030_irq_thread(void *data)
  */
 static irqreturn_t handle_twl4030_pih(int irq, void *devid)
 {
-	/* Acknowledge, clear *AND* mask the interrupt... */
-	disable_irq_nosync(irq);
-	complete(devid);
+	int		module_irq;
+	irqreturn_t	ret;
+	u8		pih_isr;
+
+	ret = twl_i2c_read_u8(TWL4030_MODULE_PIH, &pih_isr,
+			REG_PIH_ISR_P1);
+	if (ret) {
+		pr_warning("twl4030: I2C error %d reading PIH ISR\n", ret);
+		return IRQ_NONE;
+	}
+
+	/* these handlers deal with the relevant SIH irq status */
+	for (module_irq = twl4030_irq_base;
+			pih_isr;
+			pih_isr >>= 1, module_irq++) {
+		if (pih_isr & 0x1)
+			handle_nested_irq(module_irq);
+	}
+
 	return IRQ_HANDLED;
 }
 /*----------------------------------------------------------------------*/
@@ -460,113 +422,17 @@ static inline void activate_irq(int irq)
 
 /*----------------------------------------------------------------------*/
 
-static DEFINE_SPINLOCK(sih_agent_lock);
-
-static struct workqueue_struct *wq;
-
 struct sih_agent {
 	int			irq_base;
 	const struct sih	*sih;
 
 	u32			imr;
 	bool			imr_change_pending;
-	struct work_struct	mask_work;
-
-	u32			edge_change;
-	struct work_struct	edge_work;
-};
-
-static void twl4030_sih_do_mask(struct work_struct *work)
-{
-	struct sih_agent	*agent;
-	const struct sih	*sih;
-	union {
-		u8	bytes[4];
-		u32	word;
-	}			imr;
-	int			status;
 
-	agent = container_of(work, struct sih_agent, mask_work);
-
-	/* see what work we have */
-	spin_lock_irq(&sih_agent_lock);
-	if (agent->imr_change_pending) {
-		sih = agent->sih;
-		/* byte[0] gets overwritten as we write ... */
-		imr.word = cpu_to_le32(agent->imr << 8);
-		agent->imr_change_pending = false;
-	} else
-		sih = NULL;
-	spin_unlock_irq(&sih_agent_lock);
-	if (!sih)
-		return;
-
-	/* write the whole mask ... simpler than subsetting it */
-	status = twl_i2c_write(sih->module, imr.bytes,
-			sih->mask[irq_line].imr_offset, sih->bytes_ixr);
-	if (status)
-		pr_err("twl4030: %s, %s --> %d\n", __func__,
-				"write", status);
-}
-
-static void twl4030_sih_do_edge(struct work_struct *work)
-{
-	struct sih_agent	*agent;
-	const struct sih	*sih;
-	u8			bytes[6];
 	u32			edge_change;
-	int			status;
-
-	agent = container_of(work, struct sih_agent, edge_work);
-
-	/* see what work we have */
-	spin_lock_irq(&sih_agent_lock);
-	edge_change = agent->edge_change;
-	agent->edge_change = 0;
-	sih = edge_change ? agent->sih : NULL;
-	spin_unlock_irq(&sih_agent_lock);
-	if (!sih)
-		return;
-
-	/* Read, reserving first byte for write scratch.  Yes, this
-	 * could be cached for some speedup ... but be careful about
-	 * any processor on the other IRQ line, EDR registers are
-	 * shared.
-	 */
-	status = twl_i2c_read(sih->module, bytes + 1,
-			sih->edr_offset, sih->bytes_edr);
-	if (status) {
-		pr_err("twl4030: %s, %s --> %d\n", __func__,
-				"read", status);
-		return;
-	}
-
-	/* Modify only the bits we know must change */
-	while (edge_change) {
-		int		i = fls(edge_change) - 1;
-		struct irq_data	*idata = irq_get_irq_data(i + agent->irq_base);
-		int		byte = 1 + (i >> 2);
-		int		off = (i & 0x3) * 2;
-		unsigned int	type;
-
-		bytes[byte] &= ~(0x03 << off);
 
-		type = irqd_get_trigger_type(idata);
-		if (type & IRQ_TYPE_EDGE_RISING)
-			bytes[byte] |= BIT(off + 1);
-		if (type & IRQ_TYPE_EDGE_FALLING)
-			bytes[byte] |= BIT(off + 0);
-
-		edge_change &= ~BIT(i);
-	}
-
-	/* Write */
-	status = twl_i2c_write(sih->module, bytes,
-			sih->edr_offset, sih->bytes_edr);
-	if (status)
-		pr_err("twl4030: %s, %s --> %d\n", __func__,
-				"write", status);
-}
+	struct mutex		irq_lock;
+};
 
 /*----------------------------------------------------------------------*/
 
@@ -579,50 +445,125 @@ static void twl4030_sih_do_edge(struct work_struct *work)
 
 static void twl4030_sih_mask(struct irq_data *data)
 {
-	struct sih_agent *sih = irq_data_get_irq_chip_data(data);
-	unsigned long flags;
-
-	spin_lock_irqsave(&sih_agent_lock, flags);
-	sih->imr |= BIT(data->irq - sih->irq_base);
-	sih->imr_change_pending = true;
-	queue_work(wq, &sih->mask_work);
-	spin_unlock_irqrestore(&sih_agent_lock, flags);
+	struct sih_agent *agent = irq_data_get_irq_chip_data(data);
+
+	agent->imr |= BIT(data->irq - agent->irq_base);
+	agent->imr_change_pending = true;
 }
 
 static void twl4030_sih_unmask(struct irq_data *data)
 {
-	struct sih_agent *sih = irq_data_get_irq_chip_data(data);
-	unsigned long flags;
-
-	spin_lock_irqsave(&sih_agent_lock, flags);
-	sih->imr &= ~BIT(data->irq - sih->irq_base);
-	sih->imr_change_pending = true;
-	queue_work(wq, &sih->mask_work);
-	spin_unlock_irqrestore(&sih_agent_lock, flags);
+	struct sih_agent *agent = irq_data_get_irq_chip_data(data);
+
+	agent->imr &= ~BIT(data->irq - agent->irq_base);
+	agent->imr_change_pending = true;
 }
 
 static int twl4030_sih_set_type(struct irq_data *data, unsigned trigger)
 {
-	struct sih_agent *sih = irq_data_get_irq_chip_data(data);
-	unsigned long flags;
+	struct sih_agent *agent = irq_data_get_irq_chip_data(data);
 
 	if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
 		return -EINVAL;
 
-	spin_lock_irqsave(&sih_agent_lock, flags);
-	if (irqd_get_trigger_type(data) != trigger) {
-		sih->edge_change |= BIT(data->irq - sih->irq_base);
-		queue_work(wq, &sih->edge_work);
-	}
-	spin_unlock_irqrestore(&sih_agent_lock, flags);
+	if (irqd_get_trigger_type(data) != trigger)
+		agent->edge_change |= BIT(data->irq - agent->irq_base);
+
 	return 0;
 }
 
+static void twl4030_sih_bus_lock(struct irq_data *data)
+{
+	struct sih_agent	*agent = irq_data_get_irq_chip_data(data);
+
+	mutex_lock(&agent->irq_lock);
+}
+
+static void twl4030_sih_bus_sync_unlock(struct irq_data *data)
+{
+	struct sih_agent	*agent = irq_data_get_irq_chip_data(data);
+	const struct sih	*sih = agent->sih;
+	int			status;
+
+	if (agent->imr_change_pending) {
+		union {
+			u32	word;
+			u8	bytes[4];
+		} imr;
+
+		/* byte[0] gets overwriten as we write ... */
+		imr.word = cpu_to_le32(agent->imr << 8);
+		agent->imr_change_pending = false;
+
+		/* write the whole mask ... simpler than subsetting it */
+		status = twl_i2c_write(sih->module, imr.bytes,
+				sih->mask[irq_line].imr_offset,
+				sih->bytes_ixr);
+		if (status)
+			pr_err("twl4030: %s, %s --> %d\n", __func__,
+					"write", status);
+	}
+
+	if (agent->edge_change) {
+		u32		edge_change;
+		u8		bytes[6];
+
+		edge_change = agent->edge_change;
+		agent->edge_change = 0;
+
+		/*
+		 * Read, reserving first byte for write scratch.  Yes, this
+		 * could be cached for some speedup ... but be careful about
+		 * any processor on the other IRQ line, EDR registers are
+		 * shared.
+		 */
+		status = twl_i2c_read(sih->module, bytes + 1,
+				sih->edr_offset, sih->bytes_edr);
+		if (status) {
+			pr_err("twl4030: %s, %s --> %d\n", __func__,
+					"read", status);
+			return;
+		}
+
+		/* Modify only the bits we know must change */
+		while (edge_change) {
+			int		i = fls(edge_change) - 1;
+			struct irq_data	*idata;
+			int		byte = 1 + (i >> 2);
+			int		off = (i & 0x3) * 2;
+			unsigned int	type;
+
+			idata = irq_get_irq_data(i + agent->irq_base);
+
+			bytes[byte] &= ~(0x03 << off);
+
+			type = irqd_get_trigger_type(idata);
+			if (type & IRQ_TYPE_EDGE_RISING)
+				bytes[byte] |= BIT(off + 1);
+			if (type & IRQ_TYPE_EDGE_FALLING)
+				bytes[byte] |= BIT(off + 0);
+
+			edge_change &= ~BIT(i);
+		}
+
+		/* Write */
+		status = twl_i2c_write(sih->module, bytes,
+				sih->edr_offset, sih->bytes_edr);
+		if (status)
+			pr_err("twl4030: %s, %s --> %d\n", __func__,
+					"write", status);
+	}
+
+	mutex_unlock(&agent->irq_lock);
+}
+
 static struct irq_chip twl4030_sih_irq_chip = {
 	.name		= "twl4030",
-	.irq_mask      	= twl4030_sih_mask,
+	.irq_mask	= twl4030_sih_mask,
 	.irq_unmask	= twl4030_sih_unmask,
 	.irq_set_type	= twl4030_sih_set_type,
+	.irq_bus_lock	= twl4030_sih_bus_lock,
+	.irq_bus_sync_unlock = twl4030_sih_bus_sync_unlock,
 };
 
 /*----------------------------------------------------------------------*/
@@ -655,9 +596,7 @@ static void handle_twl4030_sih(unsigned irq, struct irq_desc *desc)
 	int isr;
 
 	/* reading ISR acks the IRQs, using clear-on-read mode */
-	local_irq_enable();
 	isr = sih_read_isr(sih);
-	local_irq_disable();
 
 	if (isr < 0) {
 		pr_err("twl4030: %s SIH, read ISR error %d\n",
@@ -672,7 +611,7 @@ static void handle_twl4030_sih(unsigned irq, struct irq_desc *desc)
 		isr &= ~BIT(irq);
 
 		if (irq < sih->bits)
-			generic_handle_irq(agent->irq_base + irq);
+			handle_nested_irq(agent->irq_base + irq);
 		else
 			pr_err("twl4030: %s SIH, invalid ISR bit %d\n",
 				sih->name, irq);
@@ -718,15 +657,14 @@ int twl4030_sih_setup(int module)
 	agent->irq_base = irq_base;
 	agent->sih = sih;
 	agent->imr = ~0;
-	INIT_WORK(&agent->mask_work, twl4030_sih_do_mask);
-	INIT_WORK(&agent->edge_work, twl4030_sih_do_edge);
+	mutex_init(&agent->irq_lock);
 
 	for (i = 0; i < sih->bits; i++) {
 		irq = irq_base + i;
 
+		irq_set_chip_data(irq, agent);
 		irq_set_chip_and_handler(irq, &twl4030_sih_irq_chip,
 					 handle_edge_irq);
-		irq_set_chip_data(irq, agent);
 		activate_irq(irq);
 	}
 
@@ -758,7 +696,6 @@ int twl4030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
 
 	int			status;
 	int			i;
-	struct task_struct	*task;
 
 	/*
 	 * Mask and clear all TWL4030 interrupts since initially we do
@@ -768,12 +705,6 @@ int twl4030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
 	if (status < 0)
 		return status;
 
-	wq = create_singlethread_workqueue("twl4030-irqchip");
-	if (!wq) {
-		pr_err("twl4030: workqueue FAIL\n");
-		return -ESRCH;
-	}
-
 	twl4030_irq_base = irq_base;
 
 	/* install an irq handler for each of the SIH modules;
@@ -787,6 +718,7 @@ int twl4030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
 	for (i = irq_base; i < irq_end; i++) {
 		irq_set_chip_and_handler(i, &twl4030_irq_chip,
 					 handle_simple_irq);
+		irq_set_nested_thread(i, 1);
 		activate_irq(i);
 	}
 	twl4030_irq_next = i;
@@ -801,34 +733,22 @@ int twl4030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
 	}
 
 	/* install an irq handler to demultiplex the TWL4030 interrupt */
-
-
-	init_completion(&irq_event);
-
-	status = request_irq(irq_num, handle_twl4030_pih, IRQF_DISABLED,
-				"TWL4030-PIH", &irq_event);
+	status = request_threaded_irq(irq_num, NULL, handle_twl4030_pih, 0,
+					"TWL4030-PIH", NULL);
 	if (status < 0) {
 		pr_err("twl4030: could not claim irq%d: %d\n", irq_num, status);
 		goto fail_rqirq;
 	}
 
-	task = kthread_run(twl4030_irq_thread, (void *)(long)irq_num,
-								"twl4030-irq");
-	if (IS_ERR(task)) {
-		pr_err("twl4030: could not create irq %d thread!\n", irq_num);
-		status = PTR_ERR(task);
-		goto fail_kthread;
-	}
 	return status;
-fail_kthread:
-	free_irq(irq_num, &irq_event);
 fail_rqirq:
 	/* clean up twl4030_sih_setup */
 fail:
-	for (i = irq_base; i < irq_end; i++)
+	for (i = irq_base; i < irq_end; i++) {
+		irq_set_nested_thread(i, 0);
 		irq_set_chip_and_handler(i, NULL, NULL);
-	destroy_workqueue(wq);
-	wq = NULL;
+	}
+
 	return status;
 }