Commit c081197a authored by Ranjani Vaidyanathan's avatar Ranjani Vaidyanathan Committed by Shawn Guo
Browse files

firmware: imx: scu-irq: support identifying SCU wakeup source from sysfs 



Record SCU wakeup interrupt in /sys/power/pm_wakeup_irq
The user can further identify the exact wakeup source by using the
following interface:
cat /sys/firmware/scu_wakeup_source/wakeup_src

The above will print the wake groups and the irqs that could have
contributed to waking up the kernel. For example if ON/OFF button was the
wakeup source:
cat /sys/firmware/scu_wakeup_source/wakeup_src
Wakeup source group = 3, irq = 0x1

The user can refer to the SCFW API documentation to identify all the
wake groups and irqs.

Signed-off-by: default avatarRanjani Vaidyanathan <ranjani.vaidyanathan@nxp.com>
Signed-off-by: default avatarPeng Fan <peng.fan@nxp.com>
Signed-off-by: default avatarShawn Guo <shawnguo@kernel.org>
parent 6c59ce48

drivers/firmware/imx/imx-scu-irq.c

+70 −0
Original line number Diff line number Diff line
@@ -9,8 +9,10 @@ 
#include <dt-bindings/firmware/imx/rsrc.h>

#include <linux/firmware/imx/ipc.h>

#include <linux/firmware/imx/sci.h>

#include <linux/kobject.h>

#include <linux/mailbox_client.h>

#include <linux/suspend.h>

#include <linux/sysfs.h>



#define IMX_SC_IRQ_FUNC_ENABLE	1

#define IMX_SC_IRQ_FUNC_STATUS	2
@@ -40,6 +42,20 @@ struct imx_sc_msg_irq_enable { 
	u8 enable;

} __packed;



struct scu_wakeup {

	u32 mask;

	u32 wakeup_src;

	bool valid;

};



/* Sysfs functions */

static struct kobject *wakeup_obj;

static ssize_t wakeup_source_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf);

static struct kobj_attribute wakeup_source_attr =

		__ATTR(wakeup_src, 0660, wakeup_source_show, NULL);



static struct scu_wakeup scu_irq_wakeup[IMX_SC_IRQ_NUM_GROUP];



static struct imx_sc_ipc *imx_sc_irq_ipc_handle;

static struct work_struct imx_sc_irq_work;

static BLOCKING_NOTIFIER_HEAD(imx_scu_irq_notifier_chain);
@@ -71,6 +87,11 @@ static void imx_scu_irq_work_handler(struct work_struct *work) 
	u8 i;



	for (i = 0; i < IMX_SC_IRQ_NUM_GROUP; i++) {

		if (scu_irq_wakeup[i].mask) {

			scu_irq_wakeup[i].valid = false;

			scu_irq_wakeup[i].wakeup_src = 0;

		}



		ret = imx_scu_irq_get_status(i, &irq_status);

		if (ret) {

			pr_err("get irq group %d status failed, ret %d\n",
@@ -80,6 +101,12 @@ static void imx_scu_irq_work_handler(struct work_struct *work) 


		if (!irq_status)

			continue;

		if (scu_irq_wakeup[i].mask & irq_status) {

			scu_irq_wakeup[i].valid = true;

			scu_irq_wakeup[i].wakeup_src = irq_status & scu_irq_wakeup[i].mask;

		} else {

			scu_irq_wakeup[i].wakeup_src = irq_status;

		}



		pm_system_wakeup();

		imx_scu_irq_notifier_call_chain(irq_status, &i);
@@ -135,6 +162,11 @@ int imx_scu_irq_group_enable(u8 group, u32 mask, u8 enable) 
		pr_err("enable irq failed, group %d, mask %d, ret %d\n",

			group, mask, ret);



	if (enable)

		scu_irq_wakeup[group].mask |= mask;

	else

		scu_irq_wakeup[group].mask &= ~mask;



	return ret;

}

EXPORT_SYMBOL(imx_scu_irq_group_enable);
@@ -144,6 +176,25 @@ static void imx_scu_irq_callback(struct mbox_client *c, void *msg) 
	schedule_work(&imx_sc_irq_work);

}



static ssize_t wakeup_source_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf)

{

	int i;



	for (i = 0; i < IMX_SC_IRQ_NUM_GROUP; i++) {

		if (!scu_irq_wakeup[i].wakeup_src)

			continue;



		if (scu_irq_wakeup[i].valid)

			sprintf(buf, "Wakeup source group = %d, irq = 0x%x\n",

				i, scu_irq_wakeup[i].wakeup_src);

		else

			sprintf(buf, "Spurious SCU wakeup, group = %d, irq = 0x%x\n",

				i, scu_irq_wakeup[i].wakeup_src);

	}



	return strlen(buf);

}



int imx_scu_enable_general_irq_channel(struct device *dev)

{

	struct of_phandle_args spec;
@@ -183,6 +234,25 @@ int imx_scu_enable_general_irq_channel(struct device *dev) 


	mu_resource_id = IMX_SC_R_MU_0A + i;



	/* Create directory under /sysfs/firmware */

	wakeup_obj = kobject_create_and_add("scu_wakeup_source", firmware_kobj);

	if (!wakeup_obj) {

		ret = -ENOMEM;

		goto free_ch;

	}



	ret = sysfs_create_file(wakeup_obj, &wakeup_source_attr.attr);

	if (ret) {

		dev_err(dev, "Cannot create wakeup source src file......\n");

		kobject_put(wakeup_obj);

		goto free_ch;

	}



	return 0;



free_ch:

	mbox_free_channel(ch);



	return ret;

}

EXPORT_SYMBOL(imx_scu_enable_general_irq_channel);