[PATCH V5 07/13] boot_constraint: Add debugfs support

Viresh Kumar
2017-12-14T15:34:16Z

This patch adds debugfs support for boot constraints. This is how it
looks for a "vmmc-supply" constraint for the MMC device.

$ ls -R /sys/kernel/debug/boot_constraints/
/sys/kernel/debug/boot_constraints/:
f723d000.dwmmc0

/sys/kernel/debug/boot_constraints/f723d000.dwmmc0:
clk-ciu pm-domain supply-vmmc supply-vmmcaux

/sys/kernel/debug/boot_constraints/f723d000.dwmmc0/clk-ciu:

/sys/kernel/debug/boot_constraints/f723d000.dwmmc0/pm-domain:

/sys/kernel/debug/boot_constraints/f723d000.dwmmc0/supply-vmmc:
u_volt_max u_volt_min

/sys/kernel/debug/boot_constraints/f723d000.dwmmc0/supply-vmmcaux:
u_volt_max u_volt_min

Tested-by: Rajendra Nayak <rnayak@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
drivers/boot_constraint/clk.c | 3 ++
drivers/boot_constraint/core.c | 59 ++++++++++++++++++++++++++++++++++++++++
drivers/boot_constraint/core.h | 6 ++++
drivers/boot_constraint/pm.c | 11 ++++++--
drivers/boot_constraint/supply.c | 9 ++++++
5 files changed, 86 insertions(+), 2 deletions(-)

diff --git a/drivers/boot_constraint/clk.c b/drivers/boot_constraint/clk.c
index db22acff43e6..ebc871c29a83 100644
--- a/drivers/boot_constraint/clk.c
+++ b/drivers/boot_constraint/clk.c
@@ -46,6 +46,8 @@ int constraint_clk_add(struct constraint *constraint, void *data)
cclk->clk_info.name = kstrdup_const(clk_info->name, GFP_KERNEL);
constraint->private = cclk;

+ constraint_add_debugfs(constraint, clk_info->name);
+
return 0;

put_clk:
@@ -60,6 +62,7 @@ void constraint_clk_remove(struct constraint *constraint)
{
struct constraint_clk *cclk = constraint->private;

+ constraint_remove_debugfs(constraint);
kfree_const(cclk->clk_info.name);
clk_disable_unprepare(cclk->clk);
clk_put(cclk->clk);
diff --git a/drivers/boot_constraint/core.c b/drivers/boot_constraint/core.c
index b36c02aa50c5..0350c5057ee5 100644
--- a/drivers/boot_constraint/core.c
+++ b/drivers/boot_constraint/core.c
@@ -21,6 +21,63 @@
static LIST_HEAD(constraint_devices);
static DEFINE_MUTEX(constraint_devices_mutex);

+/* Debugfs */
+
+static struct dentry *rootdir;
+
+static void constraint_device_add_debugfs(struct constraint_dev *cdev)
+{
+ struct device *dev = cdev->dev;
+
+ cdev->dentry = debugfs_create_dir(dev_name(dev), rootdir);
+}
+
+static void constraint_device_remove_debugfs(struct constraint_dev *cdev)
+{
+ debugfs_remove_recursive(cdev->dentry);
+}
+
+void constraint_add_debugfs(struct constraint *constraint, const char *suffix)
+{
+ struct device *dev = constraint->cdev->dev;
+ const char *prefix;
+ char name[NAME_MAX];
+
+ switch (constraint->type) {
+ case DEV_BOOT_CONSTRAINT_CLK:
+ prefix = "clk";
+ break;
+ case DEV_BOOT_CONSTRAINT_PM:
+ prefix = "pm";
+ break;
+ case DEV_BOOT_CONSTRAINT_SUPPLY:
+ prefix = "supply";
+ break;
+ default:
+ dev_err(dev, "%s: Constraint type (%d) not supported\n",
+ __func__, constraint->type);
+ return;
+ }
+
+ snprintf(name, NAME_MAX, "%s-%s", prefix, suffix);
+
+ constraint->dentry = debugfs_create_dir(name, constraint->cdev->dentry);
+}
+
+void constraint_remove_debugfs(struct constraint *constraint)
+{
+ debugfs_remove_recursive(constraint->dentry);
+}
+
+static int __init constraint_debugfs_init(void)
+{
+ rootdir = debugfs_create_dir("boot_constraints", NULL);
+
+ return 0;
+}
+core_initcall(constraint_debugfs_init);
+
+
/* Boot constraints core */

static struct constraint_dev *constraint_device_find(struct device *dev)
@@ -48,12 +105,14 @@ static struct constraint_dev *constraint_device_allocate(struct device *dev)
INIT_LIST_HEAD(&cdev->constraints);

list_add(&cdev->node, &constraint_devices);
+ constraint_device_add_debugfs(cdev);

return cdev;
}

static void constraint_device_free(struct constraint_dev *cdev)
{
+ constraint_device_remove_debugfs(cdev);
list_del(&cdev->node);
kfree(cdev);
}
diff --git a/drivers/boot_constraint/core.h b/drivers/boot_constraint/core.h
index c5b27617b4ae..9dd481d38b99 100644
--- a/drivers/boot_constraint/core.h
+++ b/drivers/boot_constraint/core.h
@@ -7,6 +7,7 @@
#define _CORE_H

#include <linux/boot_constraint.h>
+#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/list.h>

@@ -14,6 +15,7 @@ struct constraint_dev {
struct device *dev;
struct list_head node;
struct list_head constraints;
+ struct dentry *dentry;
};

struct constraint {
@@ -22,12 +24,16 @@ struct constraint {
enum dev_boot_constraint_type type;
void (*free_resources)(void *data);
void *free_resources_data;
+ struct dentry *dentry;

int (*add)(struct constraint *constraint, void *data);
void (*remove)(struct constraint *constraint);
void *private;
};

+void constraint_add_debugfs(struct constraint *constraint, const char *suffix);
+void constraint_remove_debugfs(struct constraint *constraint);
+
/* Forward declarations of constraint specific callbacks */
int constraint_clk_add(struct constraint *constraint, void *data);
void constraint_clk_remove(struct constraint *constraint);
diff --git a/drivers/boot_constraint/pm.c b/drivers/boot_constraint/pm.c
index 4950ec6b248b..584d3d46ef65 100644
--- a/drivers/boot_constraint/pm.c
+++ b/drivers/boot_constraint/pm.c
@@ -11,11 +11,18 @@
int constraint_pm_add(struct constraint *constraint, void *data)
{
struct device *dev = constraint->cdev->dev;
+ int ret;

- return dev_pm_domain_attach(dev, true);
+ ret = dev_pm_domain_attach(dev, true);
+ if (ret)
+ return ret;
+
+ constraint_add_debugfs(constraint, "domain");
+
+ return 0;
}

void constraint_pm_remove(struct constraint *constraint)
{
- /* Nothing to do for now */
+ constraint_remove_debugfs(constraint);
}
diff --git a/drivers/boot_constraint/supply.c b/drivers/boot_constraint/supply.c
index 916e5d6848d5..28fda60a0711 100644
--- a/drivers/boot_constraint/supply.c
+++ b/drivers/boot_constraint/supply.c
@@ -57,6 +57,14 @@ int constraint_supply_add(struct constraint *constraint, void *data)
csupply->supply.name = kstrdup_const(supply->name, GFP_KERNEL);
constraint->private = csupply;

+ constraint_add_debugfs(constraint, supply->name);
+
+ debugfs_create_u32("u_volt_min", 0444, constraint->dentry,
+ &csupply->supply.u_volt_min);
+
+ debugfs_create_u32("u_volt_max", 0444, constraint->dentry,
+ &csupply->supply.u_volt_max);
+
return 0;

remove_voltage:
@@ -77,6 +85,7 @@ void constraint_supply_remove(struct constraint *constraint)
struct device *dev = constraint->cdev->dev;
int ret;

+ constraint_remove_debugfs(constraint);
kfree_const(supply->name);

ret = regulator_disable(csupply->reg);
--
2.15.0.194.g9af6a3dea062