arch/arm/mach-omap2/prm44xx.c - kernel/msm-4.19 - Gitiles

 /*
  * OMAP4 PRM module functions
  *
  * Copyright (C) 2011 Texas Instruments, Inc.
  * Copyright (C) 2010 Nokia Corporation
  * Benoît Cousson
  * Paul Walmsley
  *
  * 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.
  */

 #include <linux/kernel.h>
 #include <linux/delay.h>
 #include <linux/errno.h>
 #include <linux/err.h>
 #include <linux/io.h>

 #include <plat/cpu.h>
 #include <plat/irqs.h>
 #include <plat/prcm.h>

 #include "iomap.h"
 #include "common.h"
 #include "vp.h"
 #include "prm44xx.h"
 #include "prm-regbits-44xx.h"
 #include "prcm44xx.h"
 #include "prminst44xx.h"

 static const struct omap_prcm_irq omap4_prcm_irqs[] = {
 	OMAP_PRCM_IRQ("wkup",   0,      0),
 	OMAP_PRCM_IRQ("io",     9,      1),
 };

 static struct omap_prcm_irq_setup omap4_prcm_irq_setup = {
 	.ack			= OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
 	.mask			= OMAP4_PRM_IRQENABLE_MPU_OFFSET,
 	.nr_regs		= 2,
 	.irqs			= omap4_prcm_irqs,
 	.nr_irqs		= ARRAY_SIZE(omap4_prcm_irqs),
 	.irq			= OMAP44XX_IRQ_PRCM,
 	.read_pending_irqs	= &omap44xx_prm_read_pending_irqs,
 	.ocp_barrier		= &omap44xx_prm_ocp_barrier,
 	.save_and_clear_irqen	= &omap44xx_prm_save_and_clear_irqen,
 	.restore_irqen		= &omap44xx_prm_restore_irqen,
 };

 /* PRM low-level functions */

 /* Read a register in a CM/PRM instance in the PRM module */
 u32 omap4_prm_read_inst_reg(s16 inst, u16 reg)
 {
 	return __raw_readl(OMAP44XX_PRM_REGADDR(inst, reg));
 }

 /* Write into a register in a CM/PRM instance in the PRM module */
 void omap4_prm_write_inst_reg(u32 val, s16 inst, u16 reg)
 {
 	__raw_writel(val, OMAP44XX_PRM_REGADDR(inst, reg));
 }

 /* Read-modify-write a register in a PRM module. Caller must lock */
 u32 omap4_prm_rmw_inst_reg_bits(u32 mask, u32 bits, s16 inst, s16 reg)
 {
 	u32 v;

 	v = omap4_prm_read_inst_reg(inst, reg);
 	v &= ~mask;
 	v |= bits;
 	omap4_prm_write_inst_reg(v, inst, reg);

 	return v;
 }

 /* PRM VP */

 /*
  * struct omap4_vp - OMAP4 VP register access description.
  * @irqstatus_mpu: offset to IRQSTATUS_MPU register for VP
  * @tranxdone_status: VP_TRANXDONE_ST bitmask in PRM_IRQSTATUS_MPU reg
  */
 struct omap4_vp {
 	u32 irqstatus_mpu;
 	u32 tranxdone_status;
 };

 static struct omap4_vp omap4_vp[] = {
 	[OMAP4_VP_VDD_MPU_ID] = {
 		.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET,
 		.tranxdone_status = OMAP4430_VP_MPU_TRANXDONE_ST_MASK,
 	},
 	[OMAP4_VP_VDD_IVA_ID] = {
 		.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
 		.tranxdone_status = OMAP4430_VP_IVA_TRANXDONE_ST_MASK,
 	},
 	[OMAP4_VP_VDD_CORE_ID] = {
 		.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
 		.tranxdone_status = OMAP4430_VP_CORE_TRANXDONE_ST_MASK,
 	},
 };

 u32 omap4_prm_vp_check_txdone(u8 vp_id)
 {
 	struct omap4_vp *vp = &omap4_vp[vp_id];
 	u32 irqstatus;

 	irqstatus = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
 						OMAP4430_PRM_OCP_SOCKET_INST,
 						vp->irqstatus_mpu);
 	return irqstatus & vp->tranxdone_status;
 }

 void omap4_prm_vp_clear_txdone(u8 vp_id)
 {
 	struct omap4_vp *vp = &omap4_vp[vp_id];

 	omap4_prminst_write_inst_reg(vp->tranxdone_status,
 				     OMAP4430_PRM_PARTITION,
 				     OMAP4430_PRM_OCP_SOCKET_INST,
 				     vp->irqstatus_mpu);
 };

 u32 omap4_prm_vcvp_read(u8 offset)
 {
 	return omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
 					   OMAP4430_PRM_DEVICE_INST, offset);
 }

 void omap4_prm_vcvp_write(u32 val, u8 offset)
 {
 	omap4_prminst_write_inst_reg(val, OMAP4430_PRM_PARTITION,
 				     OMAP4430_PRM_DEVICE_INST, offset);
 }

 u32 omap4_prm_vcvp_rmw(u32 mask, u32 bits, u8 offset)
 {
 	return omap4_prminst_rmw_inst_reg_bits(mask, bits,
 					       OMAP4430_PRM_PARTITION,
 					       OMAP4430_PRM_DEVICE_INST,
 					       offset);
 }

 static inline u32 _read_pending_irq_reg(u16 irqen_offs, u16 irqst_offs)
 {
 	u32 mask, st;

 	/* XXX read mask from RAM? */
 	mask = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
 				       irqen_offs);
 	st = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST, irqst_offs);

 	return mask & st;
 }

 /**
  * omap44xx_prm_read_pending_irqs - read pending PRM MPU IRQs into @events
  * @events: ptr to two consecutive u32s, preallocated by caller
  *
  * Read PRM_IRQSTATUS_MPU* bits, AND'ed with the currently-enabled PRM
  * MPU IRQs, and store the result into the two u32s pointed to by @events.
  * No return value.
  */
 void omap44xx_prm_read_pending_irqs(unsigned long *events)
 {
 	events[0] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_OFFSET,
 					  OMAP4_PRM_IRQSTATUS_MPU_OFFSET);

 	events[1] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_2_OFFSET,
 					  OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);
 }

 /**
  * omap44xx_prm_ocp_barrier - force buffered MPU writes to the PRM to complete
  *
  * Force any buffered writes to the PRM IP block to complete.  Needed
  * by the PRM IRQ handler, which reads and writes directly to the IP
  * block, to avoid race conditions after acknowledging or clearing IRQ
  * bits.  No return value.
  */
 void omap44xx_prm_ocp_barrier(void)
 {
 	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
 				OMAP4_REVISION_PRM_OFFSET);
 }

 /**
  * omap44xx_prm_save_and_clear_irqen - save/clear PRM_IRQENABLE_MPU* regs
  * @saved_mask: ptr to a u32 array to save IRQENABLE bits
  *
  * Save the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers to
  * @saved_mask.  @saved_mask must be allocated by the caller.
  * Intended to be used in the PRM interrupt handler suspend callback.
  * The OCP barrier is needed to ensure the write to disable PRM
  * interrupts reaches the PRM before returning; otherwise, spurious
  * interrupts might occur.  No return value.
  */
 void omap44xx_prm_save_and_clear_irqen(u32 *saved_mask)
 {
 	saved_mask[0] =
 		omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
 					OMAP4_PRM_IRQSTATUS_MPU_OFFSET);
 	saved_mask[1] =
 		omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
 					OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);

 	omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
 				 OMAP4_PRM_IRQENABLE_MPU_OFFSET);
 	omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
 				 OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);

 	/* OCP barrier */
 	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
 				OMAP4_REVISION_PRM_OFFSET);
 }

 /**
  * omap44xx_prm_restore_irqen - set PRM_IRQENABLE_MPU* registers from args
  * @saved_mask: ptr to a u32 array of IRQENABLE bits saved previously
  *
  * Restore the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers from
  * @saved_mask.  Intended to be used in the PRM interrupt handler resume
  * callback to restore values saved by omap44xx_prm_save_and_clear_irqen().
  * No OCP barrier should be needed here; any pending PRM interrupts will fire
  * once the writes reach the PRM.  No return value.
  */
 void omap44xx_prm_restore_irqen(u32 *saved_mask)
 {
 	omap4_prm_write_inst_reg(saved_mask[0], OMAP4430_PRM_OCP_SOCKET_INST,
 				 OMAP4_PRM_IRQENABLE_MPU_OFFSET);
 	omap4_prm_write_inst_reg(saved_mask[1], OMAP4430_PRM_OCP_SOCKET_INST,
 				 OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);
 }

 /**
  * omap44xx_prm_reconfigure_io_chain - clear latches and reconfigure I/O chain
  *
  * Clear any previously-latched I/O wakeup events and ensure that the
  * I/O wakeup gates are aligned with the current mux settings.  Works
  * by asserting WUCLKIN, waiting for WUCLKOUT to be asserted, and then
  * deasserting WUCLKIN and waiting for WUCLKOUT to be deasserted.
  * No return value. XXX Are the final two steps necessary?
  */
 void omap44xx_prm_reconfigure_io_chain(void)
 {
 	int i = 0;

 	/* Trigger WUCLKIN enable */
 	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK,
 				    OMAP4430_WUCLK_CTRL_MASK,
 				    OMAP4430_PRM_DEVICE_INST,
 				    OMAP4_PRM_IO_PMCTRL_OFFSET);
 	omap_test_timeout(
 		(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
 					   OMAP4_PRM_IO_PMCTRL_OFFSET) &
 		   OMAP4430_WUCLK_STATUS_MASK) >>
 		  OMAP4430_WUCLK_STATUS_SHIFT) == 1),
 		MAX_IOPAD_LATCH_TIME, i);
 	if (i == MAX_IOPAD_LATCH_TIME)
 		pr_warn("PRM: I/O chain clock line assertion timed out\n");

 	/* Trigger WUCLKIN disable */
 	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK, 0x0,
 				    OMAP4430_PRM_DEVICE_INST,
 				    OMAP4_PRM_IO_PMCTRL_OFFSET);
 	omap_test_timeout(
 		(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
 					   OMAP4_PRM_IO_PMCTRL_OFFSET) &
 		   OMAP4430_WUCLK_STATUS_MASK) >>
 		  OMAP4430_WUCLK_STATUS_SHIFT) == 0),
 		MAX_IOPAD_LATCH_TIME, i);
 	if (i == MAX_IOPAD_LATCH_TIME)
 		pr_warn("PRM: I/O chain clock line deassertion timed out\n");

 	return;
 }

 /**
  * omap44xx_prm_enable_io_wakeup - enable wakeup events from I/O wakeup latches
  *
  * Activates the I/O wakeup event latches and allows events logged by
  * those latches to signal a wakeup event to the PRCM.  For I/O wakeups
  * to occur, WAKEUPENABLE bits must be set in the pad mux registers, and
  * omap44xx_prm_reconfigure_io_chain() must be called.  No return value.
  */
 static void __init omap44xx_prm_enable_io_wakeup(void)
 {
 	omap4_prm_rmw_inst_reg_bits(OMAP4430_GLOBAL_WUEN_MASK,
 				    OMAP4430_GLOBAL_WUEN_MASK,
 				    OMAP4430_PRM_DEVICE_INST,
 				    OMAP4_PRM_IO_PMCTRL_OFFSET);
 }

 static int __init omap4xxx_prcm_init(void)
 {
 	if (cpu_is_omap44xx()) {
 		omap44xx_prm_enable_io_wakeup();
 		return omap_prcm_register_chain_handler(&omap4_prcm_irq_setup);
 	}
 	return 0;
 }
 subsys_initcall(omap4xxx_prcm_init);
	/*
	* OMAP4 PRM module functions
	*
	* Copyright (C) 2011 Texas Instruments, Inc.
	* Copyright (C) 2010 Nokia Corporation
	* Benoît Cousson
	* Paul Walmsley
	*
	* 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.
	*/

	#include <linux/kernel.h>
	#include <linux/delay.h>
	#include <linux/errno.h>
	#include <linux/err.h>
	#include <linux/io.h>

	#include <plat/cpu.h>
	#include <plat/irqs.h>
	#include <plat/prcm.h>

	#include "iomap.h"
	#include "common.h"
	#include "vp.h"
	#include "prm44xx.h"
	#include "prm-regbits-44xx.h"
	#include "prcm44xx.h"
	#include "prminst44xx.h"

	static const struct omap_prcm_irq omap4_prcm_irqs[] = {
	OMAP_PRCM_IRQ("wkup", 0, 0),
	OMAP_PRCM_IRQ("io", 9, 1),
	};

	static struct omap_prcm_irq_setup omap4_prcm_irq_setup = {
	.ack = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
	.mask = OMAP4_PRM_IRQENABLE_MPU_OFFSET,
	.nr_regs = 2,
	.irqs = omap4_prcm_irqs,
	.nr_irqs = ARRAY_SIZE(omap4_prcm_irqs),
	.irq = OMAP44XX_IRQ_PRCM,
	.read_pending_irqs = &omap44xx_prm_read_pending_irqs,
	.ocp_barrier = &omap44xx_prm_ocp_barrier,
	.save_and_clear_irqen = &omap44xx_prm_save_and_clear_irqen,
	.restore_irqen = &omap44xx_prm_restore_irqen,
	};

	/* PRM low-level functions */

	/* Read a register in a CM/PRM instance in the PRM module */
	u32 omap4_prm_read_inst_reg(s16 inst, u16 reg)
	{
	return __raw_readl(OMAP44XX_PRM_REGADDR(inst, reg));
	}

	/* Write into a register in a CM/PRM instance in the PRM module */
	void omap4_prm_write_inst_reg(u32 val, s16 inst, u16 reg)
	{
	__raw_writel(val, OMAP44XX_PRM_REGADDR(inst, reg));
	}

	/* Read-modify-write a register in a PRM module. Caller must lock */
	u32 omap4_prm_rmw_inst_reg_bits(u32 mask, u32 bits, s16 inst, s16 reg)
	{
	u32 v;

	v = omap4_prm_read_inst_reg(inst, reg);
	v &= ~mask;
	v \|= bits;
	omap4_prm_write_inst_reg(v, inst, reg);

	return v;
	}

	/* PRM VP */

	/*
	* struct omap4_vp - OMAP4 VP register access description.
	* @irqstatus_mpu: offset to IRQSTATUS_MPU register for VP
	* @tranxdone_status: VP_TRANXDONE_ST bitmask in PRM_IRQSTATUS_MPU reg
	*/
	struct omap4_vp {
	u32 irqstatus_mpu;
	u32 tranxdone_status;
	};

	static struct omap4_vp omap4_vp[] = {
	[OMAP4_VP_VDD_MPU_ID] = {
	.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET,
	.tranxdone_status = OMAP4430_VP_MPU_TRANXDONE_ST_MASK,
	},
	[OMAP4_VP_VDD_IVA_ID] = {
	.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
	.tranxdone_status = OMAP4430_VP_IVA_TRANXDONE_ST_MASK,
	},
	[OMAP4_VP_VDD_CORE_ID] = {
	.irqstatus_mpu = OMAP4_PRM_IRQSTATUS_MPU_OFFSET,
	.tranxdone_status = OMAP4430_VP_CORE_TRANXDONE_ST_MASK,
	},
	};

	u32 omap4_prm_vp_check_txdone(u8 vp_id)
	{
	struct omap4_vp *vp = &omap4_vp[vp_id];
	u32 irqstatus;

	irqstatus = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
	OMAP4430_PRM_OCP_SOCKET_INST,
	vp->irqstatus_mpu);
	return irqstatus & vp->tranxdone_status;
	}

	void omap4_prm_vp_clear_txdone(u8 vp_id)
	{
	struct omap4_vp *vp = &omap4_vp[vp_id];

	omap4_prminst_write_inst_reg(vp->tranxdone_status,
	OMAP4430_PRM_PARTITION,
	OMAP4430_PRM_OCP_SOCKET_INST,
	vp->irqstatus_mpu);
	};

	u32 omap4_prm_vcvp_read(u8 offset)
	{
	return omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
	OMAP4430_PRM_DEVICE_INST, offset);
	}

	void omap4_prm_vcvp_write(u32 val, u8 offset)
	{
	omap4_prminst_write_inst_reg(val, OMAP4430_PRM_PARTITION,
	OMAP4430_PRM_DEVICE_INST, offset);
	}

	u32 omap4_prm_vcvp_rmw(u32 mask, u32 bits, u8 offset)
	{
	return omap4_prminst_rmw_inst_reg_bits(mask, bits,
	OMAP4430_PRM_PARTITION,
	OMAP4430_PRM_DEVICE_INST,
	offset);
	}

	static inline u32 _read_pending_irq_reg(u16 irqen_offs, u16 irqst_offs)
	{
	u32 mask, st;

	/* XXX read mask from RAM? */
	mask = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
	irqen_offs);
	st = omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST, irqst_offs);

	return mask & st;
	}

	/**
	* omap44xx_prm_read_pending_irqs - read pending PRM MPU IRQs into @events
	* @events: ptr to two consecutive u32s, preallocated by caller
	*
	* Read PRM_IRQSTATUS_MPU* bits, AND'ed with the currently-enabled PRM
	* MPU IRQs, and store the result into the two u32s pointed to by @events.
	* No return value.
	*/
	void omap44xx_prm_read_pending_irqs(unsigned long *events)
	{
	events[0] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_OFFSET,
	OMAP4_PRM_IRQSTATUS_MPU_OFFSET);

	events[1] = _read_pending_irq_reg(OMAP4_PRM_IRQENABLE_MPU_2_OFFSET,
	OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);
	}

	/**
	* omap44xx_prm_ocp_barrier - force buffered MPU writes to the PRM to complete
	*
	* Force any buffered writes to the PRM IP block to complete. Needed
	* by the PRM IRQ handler, which reads and writes directly to the IP
	* block, to avoid race conditions after acknowledging or clearing IRQ
	* bits. No return value.
	*/
	void omap44xx_prm_ocp_barrier(void)
	{
	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_REVISION_PRM_OFFSET);
	}

	/**
	* omap44xx_prm_save_and_clear_irqen - save/clear PRM_IRQENABLE_MPU* regs
	* @saved_mask: ptr to a u32 array to save IRQENABLE bits
	*
	* Save the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers to
	* @saved_mask. @saved_mask must be allocated by the caller.
	* Intended to be used in the PRM interrupt handler suspend callback.
	* The OCP barrier is needed to ensure the write to disable PRM
	* interrupts reaches the PRM before returning; otherwise, spurious
	* interrupts might occur. No return value.
	*/
	void omap44xx_prm_save_and_clear_irqen(u32 *saved_mask)
	{
	saved_mask[0] =
	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQSTATUS_MPU_OFFSET);
	saved_mask[1] =
	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQSTATUS_MPU_2_OFFSET);

	omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQENABLE_MPU_OFFSET);
	omap4_prm_write_inst_reg(0, OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);

	/* OCP barrier */
	omap4_prm_read_inst_reg(OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_REVISION_PRM_OFFSET);
	}

	/**
	* omap44xx_prm_restore_irqen - set PRM_IRQENABLE_MPU* registers from args
	* @saved_mask: ptr to a u32 array of IRQENABLE bits saved previously
	*
	* Restore the PRM_IRQENABLE_MPU and PRM_IRQENABLE_MPU_2 registers from
	* @saved_mask. Intended to be used in the PRM interrupt handler resume
	* callback to restore values saved by omap44xx_prm_save_and_clear_irqen().
	* No OCP barrier should be needed here; any pending PRM interrupts will fire
	* once the writes reach the PRM. No return value.
	*/
	void omap44xx_prm_restore_irqen(u32 *saved_mask)
	{
	omap4_prm_write_inst_reg(saved_mask[0], OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQENABLE_MPU_OFFSET);
	omap4_prm_write_inst_reg(saved_mask[1], OMAP4430_PRM_OCP_SOCKET_INST,
	OMAP4_PRM_IRQENABLE_MPU_2_OFFSET);
	}

	/**
	* omap44xx_prm_reconfigure_io_chain - clear latches and reconfigure I/O chain
	*
	* Clear any previously-latched I/O wakeup events and ensure that the
	* I/O wakeup gates are aligned with the current mux settings. Works
	* by asserting WUCLKIN, waiting for WUCLKOUT to be asserted, and then
	* deasserting WUCLKIN and waiting for WUCLKOUT to be deasserted.
	* No return value. XXX Are the final two steps necessary?
	*/
	void omap44xx_prm_reconfigure_io_chain(void)
	{
	int i = 0;

	/* Trigger WUCLKIN enable */
	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK,
	OMAP4430_WUCLK_CTRL_MASK,
	OMAP4430_PRM_DEVICE_INST,
	OMAP4_PRM_IO_PMCTRL_OFFSET);
	omap_test_timeout(
	(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
	OMAP4_PRM_IO_PMCTRL_OFFSET) &
	OMAP4430_WUCLK_STATUS_MASK) >>
	OMAP4430_WUCLK_STATUS_SHIFT) == 1),
	MAX_IOPAD_LATCH_TIME, i);
	if (i == MAX_IOPAD_LATCH_TIME)
	pr_warn("PRM: I/O chain clock line assertion timed out\n");

	/* Trigger WUCLKIN disable */
	omap4_prm_rmw_inst_reg_bits(OMAP4430_WUCLK_CTRL_MASK, 0x0,
	OMAP4430_PRM_DEVICE_INST,
	OMAP4_PRM_IO_PMCTRL_OFFSET);
	omap_test_timeout(
	(((omap4_prm_read_inst_reg(OMAP4430_PRM_DEVICE_INST,
	OMAP4_PRM_IO_PMCTRL_OFFSET) &
	OMAP4430_WUCLK_STATUS_MASK) >>
	OMAP4430_WUCLK_STATUS_SHIFT) == 0),
	MAX_IOPAD_LATCH_TIME, i);
	if (i == MAX_IOPAD_LATCH_TIME)
	pr_warn("PRM: I/O chain clock line deassertion timed out\n");

	return;
	}

	/**
	* omap44xx_prm_enable_io_wakeup - enable wakeup events from I/O wakeup latches
	*
	* Activates the I/O wakeup event latches and allows events logged by
	* those latches to signal a wakeup event to the PRCM. For I/O wakeups
	* to occur, WAKEUPENABLE bits must be set in the pad mux registers, and
	* omap44xx_prm_reconfigure_io_chain() must be called. No return value.
	*/
	static void __init omap44xx_prm_enable_io_wakeup(void)
	{
	omap4_prm_rmw_inst_reg_bits(OMAP4430_GLOBAL_WUEN_MASK,
	OMAP4430_GLOBAL_WUEN_MASK,
	OMAP4430_PRM_DEVICE_INST,
	OMAP4_PRM_IO_PMCTRL_OFFSET);
	}

	static int __init omap4xxx_prcm_init(void)
	{
	if (cpu_is_omap44xx()) {
	omap44xx_prm_enable_io_wakeup();
	return omap_prcm_register_chain_handler(&omap4_prcm_irq_setup);
	}
	return 0;
	}
	subsys_initcall(omap4xxx_prcm_init);