All of lore.kernel.org
 help / color / mirror / Atom feed
From: Stefan Binding <sbinding@opensource.cirrus.com>
To: "Rafael J . Wysocki" <rafael@kernel.org>,
	Len Brown <lenb@kernel.org>, Mark Brown <broonie@kernel.org>,
	Liam Girdwood <lgirdwood@gmail.com>
Cc: <linux-acpi@vger.kernel.org>, <alsa-devel@alsa-project.org>,
	<linux-kernel@vger.kernel.org>, <patches@opensource.cirrus.com>,
	"Stefan Binding" <sbinding@opensource.cirrus.com>
Subject: [PATCH v6 1/2] ACPI: utils: Add api to read _SUB from ACPI
Date: Thu, 7 Jul 2022 16:10:36 +0100	[thread overview]
Message-ID: <20220707151037.3901050-2-sbinding@opensource.cirrus.com> (raw)
In-Reply-To: <20220707151037.3901050-1-sbinding@opensource.cirrus.com>

Add a wrapper function to read the _SUB string from ACPI.

Signed-off-by: Stefan Binding <sbinding@opensource.cirrus.com>
---
 drivers/acpi/utils.c | 38 ++++++++++++++++++++++++++++++++++++++
 include/linux/acpi.h |  6 ++++++
 2 files changed, 44 insertions(+)

diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c
index 3a9773a09e19..5a7b8065e77f 100644
--- a/drivers/acpi/utils.c
+++ b/drivers/acpi/utils.c
@@ -291,6 +291,44 @@ int acpi_get_local_address(acpi_handle handle, u32 *addr)
 }
 EXPORT_SYMBOL(acpi_get_local_address);
 
+#define ACPI_MAX_SUB_BUF_SIZE	9
+
+const char *acpi_get_subsystem_id(acpi_handle handle)
+{
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *obj;
+	acpi_status status;
+	const char *sub;
+	size_t len;
+
+	status = acpi_evaluate_object(handle, METHOD_NAME__SUB, NULL, &buffer);
+	if (ACPI_FAILURE(status)) {
+		acpi_handle_debug(handle, "Reading ACPI _SUB failed: %#x\n", status);
+		return ERR_PTR(-ENODATA);
+	}
+
+	obj = buffer.pointer;
+	if (obj->type == ACPI_TYPE_STRING) {
+		len = strlen(obj->string.pointer);
+		if (len < ACPI_MAX_SUB_BUF_SIZE && len > 0) {
+			sub = kstrdup(obj->string.pointer, GFP_KERNEL);
+			if (!sub)
+				sub = ERR_PTR(-ENOMEM);
+		} else {
+			acpi_handle_err(handle, "ACPI _SUB Length %zu is Invalid\n", len);
+			sub = ERR_PTR(-ENODATA);
+		}
+	} else {
+		acpi_handle_warn(handle, "Warning ACPI _SUB did not return a string\n");
+		sub = ERR_PTR(-ENODATA);
+	}
+
+	acpi_os_free(buffer.pointer);
+
+	return sub;
+}
+EXPORT_SYMBOL_GPL(acpi_get_subsystem_id);
+
 acpi_status
 acpi_evaluate_reference(acpi_handle handle,
 			acpi_string pathname,
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 2a0e95336094..447898685e09 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -762,6 +762,7 @@ static inline u64 acpi_arch_get_root_pointer(void)
 #endif
 
 int acpi_get_local_address(acpi_handle handle, u32 *addr);
+const char *acpi_get_subsystem_id(acpi_handle handle);
 
 #else	/* !CONFIG_ACPI */
 
@@ -1023,6 +1024,11 @@ static inline int acpi_get_local_address(acpi_handle handle, u32 *addr)
 	return -ENODEV;
 }
 
+static inline const char *acpi_get_subsystem_id(acpi_handle handle)
+{
+	return ERR_PTR(-ENODEV);
+}
+
 static inline int acpi_register_wakeup_handler(int wake_irq,
 	bool (*wakeup)(void *context), void *context)
 {
-- 
2.25.1


WARNING: multiple messages have this Message-ID (diff)
From: Stefan Binding <sbinding@opensource.cirrus.com>
To: "Rafael J . Wysocki" <rafael@kernel.org>,
	Len Brown <lenb@kernel.org>, Mark Brown <broonie@kernel.org>,
	Liam Girdwood <lgirdwood@gmail.com>
Cc: linux-acpi@vger.kernel.org, alsa-devel@alsa-project.org,
	Stefan Binding <sbinding@opensource.cirrus.com>,
	linux-kernel@vger.kernel.org, patches@opensource.cirrus.com
Subject: [PATCH v6 1/2] ACPI: utils: Add api to read _SUB from ACPI
Date: Thu, 7 Jul 2022 16:10:36 +0100	[thread overview]
Message-ID: <20220707151037.3901050-2-sbinding@opensource.cirrus.com> (raw)
In-Reply-To: <20220707151037.3901050-1-sbinding@opensource.cirrus.com>

Add a wrapper function to read the _SUB string from ACPI.

Signed-off-by: Stefan Binding <sbinding@opensource.cirrus.com>
---
 drivers/acpi/utils.c | 38 ++++++++++++++++++++++++++++++++++++++
 include/linux/acpi.h |  6 ++++++
 2 files changed, 44 insertions(+)

diff --git a/drivers/acpi/utils.c b/drivers/acpi/utils.c
index 3a9773a09e19..5a7b8065e77f 100644
--- a/drivers/acpi/utils.c
+++ b/drivers/acpi/utils.c
@@ -291,6 +291,44 @@ int acpi_get_local_address(acpi_handle handle, u32 *addr)
 }
 EXPORT_SYMBOL(acpi_get_local_address);
 
+#define ACPI_MAX_SUB_BUF_SIZE	9
+
+const char *acpi_get_subsystem_id(acpi_handle handle)
+{
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *obj;
+	acpi_status status;
+	const char *sub;
+	size_t len;
+
+	status = acpi_evaluate_object(handle, METHOD_NAME__SUB, NULL, &buffer);
+	if (ACPI_FAILURE(status)) {
+		acpi_handle_debug(handle, "Reading ACPI _SUB failed: %#x\n", status);
+		return ERR_PTR(-ENODATA);
+	}
+
+	obj = buffer.pointer;
+	if (obj->type == ACPI_TYPE_STRING) {
+		len = strlen(obj->string.pointer);
+		if (len < ACPI_MAX_SUB_BUF_SIZE && len > 0) {
+			sub = kstrdup(obj->string.pointer, GFP_KERNEL);
+			if (!sub)
+				sub = ERR_PTR(-ENOMEM);
+		} else {
+			acpi_handle_err(handle, "ACPI _SUB Length %zu is Invalid\n", len);
+			sub = ERR_PTR(-ENODATA);
+		}
+	} else {
+		acpi_handle_warn(handle, "Warning ACPI _SUB did not return a string\n");
+		sub = ERR_PTR(-ENODATA);
+	}
+
+	acpi_os_free(buffer.pointer);
+
+	return sub;
+}
+EXPORT_SYMBOL_GPL(acpi_get_subsystem_id);
+
 acpi_status
 acpi_evaluate_reference(acpi_handle handle,
 			acpi_string pathname,
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 2a0e95336094..447898685e09 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -762,6 +762,7 @@ static inline u64 acpi_arch_get_root_pointer(void)
 #endif
 
 int acpi_get_local_address(acpi_handle handle, u32 *addr);
+const char *acpi_get_subsystem_id(acpi_handle handle);
 
 #else	/* !CONFIG_ACPI */
 
@@ -1023,6 +1024,11 @@ static inline int acpi_get_local_address(acpi_handle handle, u32 *addr)
 	return -ENODEV;
 }
 
+static inline const char *acpi_get_subsystem_id(acpi_handle handle)
+{
+	return ERR_PTR(-ENODEV);
+}
+
 static inline int acpi_register_wakeup_handler(int wake_irq,
 	bool (*wakeup)(void *context), void *context)
 {
-- 
2.25.1


  reply	other threads:[~2022-07-07 15:11 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-07-07 15:10 [PATCH v6 0/2] Read _SUB from ACPI to be able to identify firmware Stefan Binding
2022-07-07 15:10 ` Stefan Binding
2022-07-07 15:10 ` Stefan Binding [this message]
2022-07-07 15:10   ` [PATCH v6 1/2] ACPI: utils: Add api to read _SUB from ACPI Stefan Binding
2022-07-14 18:24   ` Rafael J. Wysocki
2022-07-14 18:24     ` Rafael J. Wysocki
2022-07-07 15:10 ` [PATCH v6 2/2] ASoC: cs35l41: Read System Name from ACPI _SUB to identify firmware Stefan Binding
2022-07-07 15:10   ` Stefan Binding
2022-07-15 17:22 ` [PATCH v6 0/2] Read _SUB from ACPI to be able " Mark Brown
2022-07-15 17:22   ` Mark Brown

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20220707151037.3901050-2-sbinding@opensource.cirrus.com \
    --to=sbinding@opensource.cirrus.com \
    --cc=alsa-devel@alsa-project.org \
    --cc=broonie@kernel.org \
    --cc=lenb@kernel.org \
    --cc=lgirdwood@gmail.com \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=patches@opensource.cirrus.com \
    --cc=rafael@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.