Commit 9297a0e7 authored by David Brownell's avatar David Brownell Committed by Samuel Ortiz
Browse files

mfd: twl4030-core irq simplification 



Simplify twl4030 IRQ handling by removing a needless custom flow
handler.  The top level IRQs, from the PIH, are well suited for
handle_simple_irq() ... they can't be acked or masked.

Switching resolves some issues with how IRQs were dispatched.
Notably, abuse of desc->status, IRQ accounting, and handling
of various faults.

In short, use standard genirq code.

Drivers that request_irq() to the PIH will need to pay more
attention to things like setting IRQF_DISABLED (since it's
no longer ignored), and making I2C calls from handlers (you'll
need a lockdep workaround).

Signed-off-by: default avatarDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
Signed-off-by: default avatarSamuel Ortiz <sameo@openedhand.com>
parent 26b8f5e1

drivers/mfd/twl4030-core.c

+2 −66
Original line number Diff line number Diff line
@@ -535,68 +535,6 @@ EXPORT_SYMBOL(twl4030_i2c_read_u8); 


/*----------------------------------------------------------------------*/



/*

 * do_twl4030_module_irq() is the desc->handle method for each of the twl4030

 * module interrupts that doesn't chain to another irq_chip (GPIO, power, etc).

 * It executes in kernel thread context.  On entry, cpu interrupts are disabled.

 */

static void do_twl4030_module_irq(unsigned int irq, irq_desc_t *desc)

{

	struct irqaction *action;

	const unsigned int cpu = smp_processor_id();



	/*

	 * Earlier this was desc->triggered = 1;

	 */

	desc->status |= IRQ_LEVEL;



	/*

	 * The desc->handle method would normally call the desc->chip->ack

	 * method here, but we won't bother since our ack method is NULL.

	 */



	if (!desc->depth) {

		kstat_cpu(cpu).irqs[irq]++;



		action = desc->action;

		if (action) {

			int ret;

			int status = 0;

			int retval = 0;



			local_irq_enable();



			do {

				/* Call the ISR with cpu interrupts enabled */

				ret = action->handler(irq, action->dev_id);

				if (ret == IRQ_HANDLED)

					status |= action->flags;

				retval |= ret;

				action = action->next;

			} while (action);



			if (status & IRQF_SAMPLE_RANDOM)

				add_interrupt_randomness(irq);



			local_irq_disable();



			if (retval != IRQ_HANDLED)

				printk(KERN_ERR "ISR for TWL4030 module"

					" irq %d can't handle interrupt\n",

					irq);



			/*

			 * Here is where we should call the unmask method, but

			 * again we won't bother since it is NULL.

			 */

		} else

			printk(KERN_CRIT "TWL4030 module irq %d has no ISR"

					" but can't be masked!\n", irq);

	} else

		printk(KERN_CRIT "TWL4030 module irq %d is disabled but can't"

				" be masked!\n", irq);

}



static unsigned twl4030_irq_base;



static struct completion irq_event;
@@ -611,7 +549,6 @@ static int twl4030_irq_thread(void *data) 
	static unsigned i2c_errors;

	const static unsigned max_i2c_errors = 100;



	daemonize("twl4030-irq");

	current->flags |= PF_NOFREEZE;



	while (!kthread_should_stop()) {
@@ -691,8 +628,7 @@ static struct task_struct * __init start_twl4030_irq_thread(long irq) 
	struct task_struct *thread;



	init_completion(&irq_event);

	thread = kthread_run(twl4030_irq_thread, (void *)irq,

			     "twl4030 irq %ld", irq);

	thread = kthread_run(twl4030_irq_thread, (void *)irq, "twl4030-irq");

	if (!thread)

		pr_err("%s: could not create twl4030 irq %ld thread!\n",

		       DRIVER_NAME, irq);
@@ -1126,7 +1062,7 @@ static void twl_init_irq(int irq_num, unsigned irq_base, unsigned irq_end) 
	/* install an irq handler for each of the PIH modules */

	for (i = irq_base; i < irq_end; i++) {

		set_irq_chip_and_handler(i, &twl4030_irq_chip,

				do_twl4030_module_irq);

				handle_simple_irq);

		activate_irq(i);

	}

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