ARM: tegra: power LP0/LP1 selection via sysfs

Select LP0/LP1 on runtime using sysfs node /sys/power/suspend/type.
Valid selctions/commands are:
	1. lp0
	2. lp1
	3. lp2

Change-Id: I335a8845dbfed7539ae4bf8aee3ba3b97ecb3db3
Reviewed-on: http://git-master/r/30081
Reviewed-by: Karan Jhavar <kjhavar@nvidia.com>
Reviewed-by: Aleksandr Frid <afrid@nvidia.com>
Tested-by: Karan Jhavar <kjhavar@nvidia.com>
Reviewed-by: Scott Williams <scwilliams@nvidia.com>
Reviewed-by: Varun Wadekar <vwadekar@nvidia.com>

3 files changed, 68 insertions, 19 deletions

diff --git a/arch/arm/mach-tegra/gpio.c b/arch/arm/mach-tegra/gpio.c
index 66f37f9b4d65..25d1eaa31de1 100644
--- a/arch/arm/mach-tegra/gpio.c
+++ b/arch/arm/mach-tegra/gpio.c
@@ -240,8 +240,7 @@ static int tegra_gpio_irq_set_type(unsigned int irq, unsigned int type)
 	else if (type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
 		__set_irq_handler_unlocked(irq, handle_edge_irq);
 
-	if (tegra_get_suspend_mode() == TEGRA_SUSPEND_LP0)
-		tegra_set_lp0_wake_type(irq, type);
+	tegra_set_lp0_wake_type(irq, type);
 
 	return 0;
 }
@@ -363,12 +362,10 @@ static int tegra_gpio_wake_enable(unsigned int irq, unsigned int enable)
 	struct tegra_gpio_bank *bank = get_irq_chip_data(irq);
 
 	ret = tegra_set_lp1_wake(bank->irq, enable);
+	ret |= tegra_set_lp0_wake(irq, enable);
 	if (ret)
 		return ret;
 
-	if (tegra_get_suspend_mode() == TEGRA_SUSPEND_LP0)
-		return tegra_set_lp0_wake(irq, enable);
-
 	return 0;
 }
 #endif
diff --git a/arch/arm/mach-tegra/irq.c b/arch/arm/mach-tegra/irq.c
index e9e51ba47575..3abc6da46167 100644
--- a/arch/arm/mach-tegra/irq.c
+++ b/arch/arm/mach-tegra/irq.c
@@ -270,10 +270,7 @@ static int tegra_set_wake(unsigned int irq, unsigned int enable)
 
 static int tegra_set_type(unsigned int irq, unsigned int flow_type)
 {
-	if (tegra_get_suspend_mode() == TEGRA_SUSPEND_LP0)
-		return tegra_set_lp0_wake_type(irq, flow_type);
-
-	return 0;
+	return tegra_set_lp0_wake_type(irq, flow_type);
 }
 
 static void tegra_ack(unsigned int irq)
diff --git a/arch/arm/mach-tegra/suspend.c b/arch/arm/mach-tegra/suspend.c
index dc8ff5699849..80269b5f7c59 100644
--- a/arch/arm/mach-tegra/suspend.c
+++ b/arch/arm/mach-tegra/suspend.c
@@ -22,6 +22,7 @@
 
 #include <linux/kernel.h>
 #include <linux/cpumask.h>
+#include <linux/ctype.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/sched.h>
@@ -181,6 +182,15 @@ static enum tegra_suspend_mode current_suspend_mode;
 
 static unsigned int tegra_time_in_suspend[32];
 
+struct kobject *suspend_kobj;
+
+static const char *tegra_suspend_name[TEGRA_MAX_SUSPEND_MODE] = {
+	[TEGRA_SUSPEND_NONE]	= "none",
+	[TEGRA_SUSPEND_LP2]	= "lp2",
+	[TEGRA_SUSPEND_LP1]	= "lp1",
+	[TEGRA_SUSPEND_LP0]	= "lp0",
+};
+
 #if INSTRUMENT_CLUSTER_SWITCH
 enum tegra_cluster_switch_time_id
 {
@@ -213,6 +223,49 @@ static unsigned long tegra_cluster_switch_times[tegra_cluster_switch_time_id_max
 #define cpu_number()	0
 #endif
 
+static ssize_t suspend_mode_show(struct kobject *kobj,
+					struct kobj_attribute *attr, char *buf)
+{
+	char *start = buf;
+	char *end = buf + PAGE_SIZE;
+
+	start += scnprintf(start, end - start, "%s ", \
+				tegra_suspend_name[current_suspend_mode]);
+	start += scnprintf(start, end - start, "\n");
+
+	return start - buf;
+}
+
+static ssize_t suspend_mode_store(struct kobject *kobj,
+					struct kobj_attribute *attr,
+						const char *buf, size_t n)
+{
+	int len;
+	const char *name_ptr;
+	enum tegra_suspend_mode new_mode;
+
+	name_ptr = buf;
+	while (*name_ptr && !isspace(*name_ptr))
+		name_ptr++;
+	len = name_ptr - buf;
+	if (!len)
+		goto bad_name;
+
+	for (new_mode = TEGRA_SUSPEND_NONE;				\
+				new_mode < TEGRA_MAX_SUSPEND_MODE; ++new_mode) {
+		if (!strncmp(buf, tegra_suspend_name[new_mode], len)) {
+			current_suspend_mode = new_mode;
+			break;
+		}
+	}
+
+bad_name:
+	return n;
+}
+
+static struct kobj_attribute suspend_mode_attribute =
+	__ATTR(mode, 0666, suspend_mode_show, suspend_mode_store);
+
 static inline unsigned int time_to_bin(unsigned int time)
 {
 	return fls(time);
@@ -247,7 +300,7 @@ enum tegra_suspend_mode tegra_get_suspend_mode(void)
 	if (!pdata)
 		return TEGRA_SUSPEND_NONE;
 
-	return pdata->suspend_mode;
+	return current_suspend_mode;
 }
 
 #if defined(CONFIG_PM) || defined(CONFIG_CPU_IDLE) || !defined(CONFIG_ARCH_TEGRA_2x_SOC)
@@ -678,8 +731,7 @@ void tegra_suspend_dram(bool do_lp0)
 			pr_err_ratelimited("WFI for LP1 failed for CPU %d: count %lu\n",
 					    cpu, tegra_wfi_fail_count[cpu]);
 		}
-	}
-	else {
+	} else {
 		tegra_cpu_reset_handler_enable();
 		tegra_cpu_reset_handler_restore();
 		tegra_lp0_resume_mc();
@@ -1018,16 +1070,19 @@ void __init tegra_init_suspend(struct tegra_suspend_platform_data *plat)
 #endif
 
 	current_suspend_mode = plat->suspend_mode;
+
+	/* Create /sys/power/suspend/type */
+	suspend_kobj = kobject_create_and_add("suspend", power_kobj);
+	if (suspend_kobj) {
+		if (sysfs_create_file(suspend_kobj, \
+						&suspend_mode_attribute.attr))
+			pr_err("%s: sysfs_create_file suspend type failed!", \
+								 __func__);
+	}
 }
 
-#ifdef CONFIG_DEBUG_FS
-static const char *tegra_suspend_name[TEGRA_MAX_SUSPEND_MODE] = {
-	[TEGRA_SUSPEND_NONE]	= "none",
-	[TEGRA_SUSPEND_LP2]	= "lp2",
-	[TEGRA_SUSPEND_LP1]	= "lp1",
-	[TEGRA_SUSPEND_LP0]	= "lp0",
-};
 
+#ifdef CONFIG_DEBUG_FS
 static int tegra_suspend_debug_show(struct seq_file *s, void *data)
 {
 	seq_printf(s, "%s\n", tegra_suspend_name[*(int *)s->private]);