diff mbox series

[v3,08/17] firmware: turris-mox-rwtm: Don't create own kobject type

Message ID 20240617144532.17385-9-kabel@kernel.org (mailing list archive)
State Superseded
Delegated to: Arnd Bergmann
Headers show
Series Updates for turris-mox-rwtm driver | expand

Commit Message

Marek Behún June 17, 2024, 2:45 p.m. UTC
In order to create attribute files in /sys/firmware/turris-mox-rwtm,
this driver creates it's own kobject type.

Simplify this by dropping this own kobject creation, and instead
creating standard device attribute files.

For backwards compatibility with sysfs ABI, create a symlink
/sys/firmware/turris-mox-rwtm, pointing to this device's sysfs
directory.

Signed-off-by: Marek Behún <kabel@kernel.org>
---
 drivers/firmware/turris-mox-rwtm.c | 108 ++++++++---------------------
 1 file changed, 30 insertions(+), 78 deletions(-)

Comments

Andy Shevchenko June 17, 2024, 7:57 p.m. UTC | #1
On Mon, Jun 17, 2024 at 4:45 PM Marek Behún <kabel@kernel.org> wrote:
>
> In order to create attribute files in /sys/firmware/turris-mox-rwtm,
> this driver creates it's own kobject type.
>
> Simplify this by dropping this own kobject creation, and instead
> creating standard device attribute files.
>
> For backwards compatibility with sysfs ABI, create a symlink
> /sys/firmware/turris-mox-rwtm, pointing to this device's sysfs
> directory.

...

>  #define MOX_ATTR_RO(name, format, cat)                         \
>  static ssize_t                                                 \
> -name##_show(struct kobject *kobj, struct kobj_attribute *a,    \
> +name##_show(struct device *dev, struct device_attribute *a,    \
>             char *buf)                                          \
>  {                                                              \
> -       struct mox_rwtm *rwtm = to_rwtm(kobj);  \
> +       struct mox_rwtm *rwtm = dev_get_drvdata(dev);           \
>         if (!rwtm->has_##cat)                                   \
>                 return -ENODATA;                                \
>         return sprintf(buf, format, rwtm->name);                \

At some point this should be replaced with sysfs_emit()

>  }                                                              \
> -static struct kobj_attribute mox_attr_##name = __ATTR_RO(name)
> +static DEVICE_ATTR_RO(name)
diff mbox series

Patch

diff --git a/drivers/firmware/turris-mox-rwtm.c b/drivers/firmware/turris-mox-rwtm.c
index 9c66bda2f976..9c857ba427d0 100644
--- a/drivers/firmware/turris-mox-rwtm.c
+++ b/drivers/firmware/turris-mox-rwtm.c
@@ -23,7 +23,6 @@ 
 #include <linux/mutex.h>
 #include <linux/platform_device.h>
 #include <linux/sizes.h>
-#include <linux/slab.h>
 #include <linux/sysfs.h>
 #include <linux/types.h>
 
@@ -62,13 +61,10 @@  enum mbox_cmd {
 	MBOX_CMD_OTP_WRITE	= 8,
 };
 
-struct mox_kobject;
-
 struct mox_rwtm {
 	struct device *dev;
 	struct mbox_client mbox_client;
 	struct mbox_chan *mbox;
-	struct mox_kobject *kobj;
 	struct hwrng hwrng;
 
 	struct armada_37xx_rwtm_rx_msg reply;
@@ -102,59 +98,17 @@  struct mox_rwtm {
 #endif
 };
 
-struct mox_kobject {
-	struct kobject kobj;
-	struct mox_rwtm *rwtm;
-};
-
-static inline struct kobject *rwtm_to_kobj(struct mox_rwtm *rwtm)
-{
-	return &rwtm->kobj->kobj;
-}
-
-static inline struct mox_rwtm *to_rwtm(struct kobject *kobj)
-{
-	return container_of(kobj, struct mox_kobject, kobj)->rwtm;
-}
-
-static void mox_kobj_release(struct kobject *kobj)
-{
-	kfree(to_rwtm(kobj)->kobj);
-}
-
-static const struct kobj_type mox_kobj_ktype = {
-	.release	= mox_kobj_release,
-	.sysfs_ops	= &kobj_sysfs_ops,
-};
-
-static int mox_kobj_create(struct mox_rwtm *rwtm)
-{
-	rwtm->kobj = kzalloc(sizeof(*rwtm->kobj), GFP_KERNEL);
-	if (!rwtm->kobj)
-		return -ENOMEM;
-
-	kobject_init(rwtm_to_kobj(rwtm), &mox_kobj_ktype);
-	if (kobject_add(rwtm_to_kobj(rwtm), firmware_kobj, "turris-mox-rwtm")) {
-		kobject_put(rwtm_to_kobj(rwtm));
-		return -ENXIO;
-	}
-
-	rwtm->kobj->rwtm = rwtm;
-
-	return 0;
-}
-
 #define MOX_ATTR_RO(name, format, cat)				\
 static ssize_t							\
-name##_show(struct kobject *kobj, struct kobj_attribute *a,	\
+name##_show(struct device *dev, struct device_attribute *a,	\
 	    char *buf)						\
 {								\
-	struct mox_rwtm *rwtm = to_rwtm(kobj);	\
+	struct mox_rwtm *rwtm = dev_get_drvdata(dev);		\
 	if (!rwtm->has_##cat)					\
 		return -ENODATA;				\
 	return sprintf(buf, format, rwtm->name);		\
 }								\
-static struct kobj_attribute mox_attr_##name = __ATTR_RO(name)
+static DEVICE_ATTR_RO(name)
 
 MOX_ATTR_RO(serial_number, "%016llX\n", board_info);
 MOX_ATTR_RO(board_version, "%i\n", board_info);
@@ -163,6 +117,17 @@  MOX_ATTR_RO(mac_address1, "%pM\n", board_info);
 MOX_ATTR_RO(mac_address2, "%pM\n", board_info);
 MOX_ATTR_RO(pubkey, "%s\n", pubkey);
 
+static struct attribute *turris_mox_rwtm_attrs[] = {
+	&dev_attr_serial_number.attr,
+	&dev_attr_board_version.attr,
+	&dev_attr_ram_size.attr,
+	&dev_attr_mac_address1.attr,
+	&dev_attr_mac_address2.attr,
+	&dev_attr_pubkey.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(turris_mox_rwtm);
+
 static int mox_get_status(enum mbox_cmd cmd, u32 retval)
 {
 	if (MBOX_STS_CMD(retval) != cmd)
@@ -177,16 +142,6 @@  static int mox_get_status(enum mbox_cmd cmd, u32 retval)
 		return MBOX_STS_VALUE(retval);
 }
 
-static const struct attribute *mox_rwtm_attrs[] = {
-	&mox_attr_serial_number.attr,
-	&mox_attr_board_version.attr,
-	&mox_attr_ram_size.attr,
-	&mox_attr_mac_address1.attr,
-	&mox_attr_mac_address2.attr,
-	&mox_attr_pubkey.attr,
-	NULL
-};
-
 static void mox_rwtm_rx_callback(struct mbox_client *cl, void *data)
 {
 	struct mox_rwtm *rwtm = dev_get_drvdata(cl->dev);
@@ -488,6 +443,11 @@  static inline void rwtm_unregister_debugfs(struct mox_rwtm *rwtm)
 }
 #endif
 
+static void rwtm_firmware_symlink_drop(void *parent)
+{
+	sysfs_remove_link(parent, DRIVER_NAME);
+}
+
 static int turris_mox_rwtm_probe(struct platform_device *pdev)
 {
 	struct mox_rwtm *rwtm;
@@ -504,18 +464,6 @@  static int turris_mox_rwtm_probe(struct platform_device *pdev)
 	if (!rwtm->buf)
 		return -ENOMEM;
 
-	ret = mox_kobj_create(rwtm);
-	if (ret < 0) {
-		dev_err(dev, "Cannot create turris-mox-rwtm kobject!\n");
-		return ret;
-	}
-
-	ret = sysfs_create_files(rwtm_to_kobj(rwtm), mox_rwtm_attrs);
-	if (ret < 0) {
-		dev_err(dev, "Cannot create sysfs files!\n");
-		goto put_kobj;
-	}
-
 	platform_set_drvdata(pdev, rwtm);
 
 	mutex_init(&rwtm->busy);
@@ -529,7 +477,7 @@  static int turris_mox_rwtm_probe(struct platform_device *pdev)
 		if (ret != -EPROBE_DEFER)
 			dev_err(dev, "Cannot request mailbox channel: %i\n",
 				ret);
-		goto remove_files;
+		return ret;
 	}
 
 	init_completion(&rwtm->cmd_done);
@@ -563,14 +511,19 @@  static int turris_mox_rwtm_probe(struct platform_device *pdev)
 
 	dev_info(dev, "HWRNG successfully registered\n");
 
+	/*
+	 * For sysfs ABI compatibility, create symlink
+	 * /sys/firmware/turris-mox-rwtm to this device's sysfs directory.
+	 */
+	ret = sysfs_create_link(firmware_kobj, &dev->kobj, DRIVER_NAME);
+	if (!ret)
+		devm_add_action_or_reset(dev, rwtm_firmware_symlink_drop,
+					 firmware_kobj);
+
 	return 0;
 
 free_channel:
 	mbox_free_channel(rwtm->mbox);
-remove_files:
-	sysfs_remove_files(rwtm_to_kobj(rwtm), mox_rwtm_attrs);
-put_kobj:
-	kobject_put(rwtm_to_kobj(rwtm));
 	return ret;
 }
 
@@ -579,8 +532,6 @@  static void turris_mox_rwtm_remove(struct platform_device *pdev)
 	struct mox_rwtm *rwtm = platform_get_drvdata(pdev);
 
 	rwtm_unregister_debugfs(rwtm);
-	sysfs_remove_files(rwtm_to_kobj(rwtm), mox_rwtm_attrs);
-	kobject_put(rwtm_to_kobj(rwtm));
 	mbox_free_channel(rwtm->mbox);
 }
 
@@ -598,6 +549,7 @@  static struct platform_driver turris_mox_rwtm_driver = {
 	.driver	= {
 		.name		= DRIVER_NAME,
 		.of_match_table	= turris_mox_rwtm_match,
+		.dev_groups	= turris_mox_rwtm_groups,
 	},
 };
 module_platform_driver(turris_mox_rwtm_driver);