[PATCH v5 08/11] devm-helpers: Add resource managed version of debugfs directory create function

Marek Behún
2024-03-23T16:44:31Z

A few drivers register a devm action to remove a debugfs directory,
implementing a one-liner function that calls debufs_remove_recursive().
Help drivers avoid this repeated implementations by adding managed
version of debugfs directory create function.

Use the new function devm_debugfs_create_dir() in the following
drivers:
drivers/crypto/caam/ctrl.c
drivers/gpu/drm/bridge/ti-sn65dsi86.c
drivers/hwmon/hp-wmi-sensors.c
drivers/hwmon/mr75203.c
drivers/hwmon/pmbus/pmbus_core.c

Also use the action function devm_debugfs_dir_recursive_drop() in
driver
drivers/gpio/gpio-mockup.c

As per Dan Williams' request [1], do not touch the driver
drivers/cxl/mem.c

[1] https://lore.kernel.org/linux-gpio/65d7918b358a5_1ee3129432@dwillia2-mobl3.amr.corp.intel.com.notmuch/

Signed-off-by: Marek Behún <kabel@kernel.org>
---
drivers/crypto/caam/ctrl.c | 16 +++--------
drivers/gpio/gpio-mockup.c | 11 ++------
drivers/gpu/drm/bridge/ti-sn65dsi86.c | 13 ++-------
drivers/hwmon/hp-wmi-sensors.c | 15 ++--------
drivers/hwmon/mr75203.c | 15 ++++------
drivers/hwmon/pmbus/pmbus_core.c | 16 ++++-------
include/linux/devm-helpers.h | 40 +++++++++++++++++++++++++++
7 files changed, 61 insertions(+), 65 deletions(-)

diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c
index bdf367f3f679..ea3ed9a17f1a 100644
--- a/drivers/crypto/caam/ctrl.c
+++ b/drivers/crypto/caam/ctrl.c
@@ -7,6 +7,7 @@
*/

#include <linux/device.h>
+#include <linux/devm-helpers.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
@@ -604,11 +605,6 @@ static int init_clocks(struct device *dev, const struct caam_imx_data *data)
return devm_add_action_or_reset(dev, disable_clocks, ctrlpriv);
}

-static void caam_remove_debugfs(void *root)
-{
- debugfs_remove_recursive(root);
-}
-
#ifdef CONFIG_FSL_MC_BUS
static bool check_version(struct fsl_mc_version *mc_version, u32 major,
u32 minor, u32 revision)
@@ -1058,13 +1054,9 @@ static int caam_probe(struct platform_device *pdev)
ctrlpriv->era = caam_get_era(perfmon);
ctrlpriv->domain = iommu_get_domain_for_dev(dev);

- dfs_root = debugfs_create_dir(dev_name(dev), NULL);
- if (IS_ENABLED(CONFIG_DEBUG_FS)) {
- ret = devm_add_action_or_reset(dev, caam_remove_debugfs,
- dfs_root);
- if (ret)
- return ret;
- }
+ dfs_root = devm_debugfs_create_dir(dev, dev_name(dev), NULL);
+ if (IS_ERR(dfs_root))
+ return PTR_ERR(dfs_root);

caam_debugfs_init(ctrlpriv, perfmon, dfs_root);

diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c
index 455eecf6380e..adbe0fe09490 100644
--- a/drivers/gpio/gpio-mockup.c
+++ b/drivers/gpio/gpio-mockup.c
@@ -12,6 +12,7 @@
#include <linux/cleanup.h>
#include <linux/debugfs.h>
#include <linux/device.h>
+#include <linux/devm-helpers.h>
#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
@@ -390,13 +391,6 @@ static void gpio_mockup_debugfs_setup(struct device *dev,
}
}

-static void gpio_mockup_debugfs_cleanup(void *data)
-{
- struct gpio_mockup_chip *chip = data;
-
- debugfs_remove_recursive(chip->dbg_dir);
-}
-
static void gpio_mockup_dispose_mappings(void *data)
{
struct gpio_mockup_chip *chip = data;
@@ -480,7 +474,8 @@ static int gpio_mockup_probe(struct platform_device *pdev)

gpio_mockup_debugfs_setup(dev, chip);

- return devm_add_action_or_reset(dev, gpio_mockup_debugfs_cleanup, chip);
+ return devm_add_action_or_reset(dev, devm_debugfs_dir_recursive_drop,
+ chip->dbg_dir);
}

static const struct of_device_id gpio_mockup_of_match[] = {
diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
index 84698a0b27a8..85987350f108 100644
--- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c
+++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
@@ -10,6 +10,7 @@
#include <linux/bits.h>
#include <linux/clk.h>
#include <linux/debugfs.h>
+#include <linux/devm-helpers.h>
#include <linux/gpio/consumer.h>
#include <linux/gpio/driver.h>
#include <linux/i2c.h>
@@ -427,18 +428,12 @@ static int status_show(struct seq_file *s, void *data)

DEFINE_SHOW_ATTRIBUTE(status);

-static void ti_sn65dsi86_debugfs_remove(void *data)
-{
- debugfs_remove_recursive(data);
-}
-
static void ti_sn65dsi86_debugfs_init(struct ti_sn65dsi86 *pdata)
{
struct device *dev = pdata->dev;
struct dentry *debugfs;
- int ret;

- debugfs = debugfs_create_dir(dev_name(dev), NULL);
+ debugfs = devm_debugfs_create_dir(dev, dev_name(dev), NULL);

/*
* We might get an error back if debugfs wasn't enabled in the kernel
@@ -447,10 +442,6 @@ static void ti_sn65dsi86_debugfs_init(struct ti_sn65dsi86 *pdata)
if (IS_ERR_OR_NULL(debugfs))
return;

- ret = devm_add_action_or_reset(dev, ti_sn65dsi86_debugfs_remove, debugfs);
- if (ret)
- return;
-
debugfs_create_file("status", 0600, debugfs, pdata, &status_fops);
}

diff --git a/drivers/hwmon/hp-wmi-sensors.c b/drivers/hwmon/hp-wmi-sensors.c
index b5325d0e72b9..2a7c33763ce8 100644
--- a/drivers/hwmon/hp-wmi-sensors.c
+++ b/drivers/hwmon/hp-wmi-sensors.c
@@ -23,6 +23,7 @@

#include <linux/acpi.h>
#include <linux/debugfs.h>
+#include <linux/devm-helpers.h>
#include <linux/hwmon.h>
#include <linux/jiffies.h>
#include <linux/mutex.h>
@@ -1304,12 +1305,6 @@ static int current_reading_show(struct seq_file *seqf, void *ignored)
}
DEFINE_SHOW_ATTRIBUTE(current_reading);

-/* hp_wmi_devm_debugfs_remove - devm callback for debugfs cleanup */
-static void hp_wmi_devm_debugfs_remove(void *res)
-{
- debugfs_remove_recursive(res);
-}
-
/* hp_wmi_debugfs_init - create and populate debugfs directory tree */
static void hp_wmi_debugfs_init(struct device *dev, struct hp_wmi_info *info,
struct hp_wmi_platform_events *pevents,
@@ -1320,21 +1315,15 @@ static void hp_wmi_debugfs_init(struct device *dev, struct hp_wmi_info *info,
struct dentry *debugfs;
struct dentry *entries;
struct dentry *dir;
- int err;
u8 i;

/* dev_name() gives a not-very-friendly GUID for WMI devices. */
scnprintf(buf, sizeof(buf), "hp-wmi-sensors-%u", dev->id);

- debugfs = debugfs_create_dir(buf, NULL);
+ debugfs = devm_debugfs_create_dir(dev, buf, NULL);
if (IS_ERR(debugfs))
return;

- err = devm_add_action_or_reset(dev, hp_wmi_devm_debugfs_remove,
- debugfs);
- if (err)
- return;
-
entries = debugfs_create_dir("sensor", debugfs);

for (i = 0; i < icount; i++, info++) {
diff --git a/drivers/hwmon/mr75203.c b/drivers/hwmon/mr75203.c
index 50a8b9c3f94d..50f348fca108 100644
--- a/drivers/hwmon/mr75203.c
+++ b/drivers/hwmon/mr75203.c
@@ -10,6 +10,7 @@
#include <linux/bits.h>
#include <linux/clk.h>
#include <linux/debugfs.h>
+#include <linux/devm-helpers.h>
#include <linux/hwmon.h>
#include <linux/kstrtox.h>
#include <linux/module.h>
@@ -216,17 +217,11 @@ static const struct file_operations pvt_ts_coeff_j_fops = {
.llseek = default_llseek,
};

-static void devm_pvt_ts_dbgfs_remove(void *data)
-{
- struct pvt_device *pvt = (struct pvt_device *)data;
-
- debugfs_remove_recursive(pvt->dbgfs_dir);
- pvt->dbgfs_dir = NULL;
-}
-
static int pvt_ts_dbgfs_create(struct pvt_device *pvt, struct device *dev)
{
- pvt->dbgfs_dir = debugfs_create_dir(dev_name(dev), NULL);
+ pvt->dbgfs_dir = devm_debugfs_create_dir(dev, dev_name(dev), NULL);
+ if (IS_ERR(pvt->dbgfs_dir))
+ return PTR_ERR(pvt->dbgfs_dir);

debugfs_create_u32("ts_coeff_h", 0644, pvt->dbgfs_dir,
&pvt->ts_coeff.h);
@@ -237,7 +232,7 @@ static int pvt_ts_dbgfs_create(struct pvt_device *pvt, struct device *dev)
debugfs_create_file("ts_coeff_j", 0644, pvt->dbgfs_dir, pvt,
&pvt_ts_coeff_j_fops);

- return devm_add_action_or_reset(dev, devm_pvt_ts_dbgfs_remove, pvt);
+ return 0;
}

static umode_t pvt_is_visible(const void *data, enum hwmon_sensor_types type,
diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index cb4c65a7f288..88d27bb3b69a 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -7,6 +7,7 @@
*/

#include <linux/debugfs.h>
+#include <linux/devm-helpers.h>
#include <linux/kernel.h>
#include <linux/math64.h>
#include <linux/module.h>
@@ -3336,13 +3337,6 @@ static const struct file_operations pmbus_debugfs_ops_mfr = {
.open = simple_open,
};

-static void pmbus_remove_debugfs(void *data)
-{
- struct dentry *entry = data;
-
- debugfs_remove_recursive(entry);
-}
-
static int pmbus_init_debugfs(struct i2c_client *client,
struct pmbus_data *data)
{
@@ -3357,8 +3351,9 @@ static int pmbus_init_debugfs(struct i2c_client *client,
* Create the debugfs directory for this device. Use the hwmon device
* name to avoid conflicts (hwmon numbers are globally unique).
*/
- data->debugfs = debugfs_create_dir(dev_name(data->hwmon_dev),
- pmbus_debugfs_dir);
+ data->debugfs = devm_debugfs_create_dir(data->dev,
+ dev_name(data->hwmon_dev),
+ pmbus_debugfs_dir);
if (IS_ERR_OR_NULL(data->debugfs)) {
data->debugfs = NULL;
return -ENODEV;
@@ -3542,8 +3537,7 @@ static int pmbus_init_debugfs(struct i2c_client *client,
}
}

- return devm_add_action_or_reset(data->dev,
- pmbus_remove_debugfs, data->debugfs);
+ return 0;
}
#else
static int pmbus_init_debugfs(struct i2c_client *client,
diff --git a/include/linux/devm-helpers.h b/include/linux/devm-helpers.h
index 3805551fd433..feefe152c752 100644
--- a/include/linux/devm-helpers.h
+++ b/include/linux/devm-helpers.h
@@ -23,6 +23,7 @@
* already ran.
*/

+#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/kconfig.h>
#include <linux/irqdomain.h>
@@ -130,4 +131,43 @@ static inline int devm_irq_create_mapping(struct device *dev,
return virq;
}

+static inline void devm_debugfs_dir_recursive_drop(void *res)
+{
+ debugfs_remove_recursive(res);
+}
+
+/**
+ * devm_debugfs_create_dir - Resource managed debugfs directory creation
+ * @dev: Device which lifetime the directory is bound to
+ * @name: a pointer to a string containing the name of the directory to
+ * create
+ * @parent: a pointer to the parent dentry for this file. This should be a
+ * directory dentry if set. If this parameter is NULL, then the
+ * directory will be created in the root of the debugfs filesystem.
+ *
+ * Create a debugfs directory which is automatically recursively removed when
+ * the driver is detached. A few drivers create debugfs directories which they
+ * want removed before driver is detached.
+ * devm_debugfs_create_dir() can be used to omit the explicit
+ * debugfs_remove_recursive() call when driver is detached.
+ */
+static inline struct dentry *
+devm_debugfs_create_dir(struct device *dev, const char *name,
+ struct dentry *parent)
+{
+ struct dentry *dentry;
+ int err;
+
+ dentry = debugfs_create_dir(name, parent);
+ if (IS_ERR(dentry))
+ return dentry;
+
+ err = devm_add_action_or_reset(dev, devm_debugfs_dir_recursive_drop,
+ dentry);
+ if (err < 0)
+ return ERR_PTR(err);
+
+ return dentry;
+}
+
#endif
--
2.43.2