[PATCH v3 0/2] Read _SUB from ACPI to be able to identify firmware

Stefan Binding

author

2022-06-27 15:52 UTC #0 lore raw

v3 cover Read _SUB from ACPI to be able to identify firmware

CS35L41 has a DSP which is able to run firmware, as well as a tuning file. Different systems may want to use different firmwares and tuning files, and some firmwares/tunings may not be compatible with other systems. To allow a system to select the correct fimware/tuning, we can read an _SUB from the ACPI. This _SUB can then be used to uniquely identify the system in the firmware/tuning file name.

Add a helper function which reads the _SUB, so this can be used by other parts in the future.
Add support inside the CS35L41 ASoC driver to read this _SUB, and save it appropriately.

Changes since v2:
- Fix error in function prototype

Changes since v1:
- Add length validation for SSID String
- Rename API
- Allocate memory inside API
- Use ACPI_HANDLE macro instead of ACPI_COMPANION
- Improve error handling

Stefan Binding (2):
ACPI: utils: Add api to read _SUB from ACPI
ASoC: cs35l41: Read System Name from ACPI _SUB to identify firmware

 drivers/acpi/utils.c       | 38 ++++++++++++++++++++++++++++++++++++++
 include/linux/acpi.h       |  6 ++++++
 sound/soc/codecs/cs35l41.c | 24 ++++++++++++++++++++++++
 3 files changed, 68 insertions(+)

Signature · 1 line

2.25.1

Stefan Binding

author

2022-06-27 15:52 UTC #1 lore raw

PATCH v3 1/2 ACPI: utils: Add api to read _SUB from ACPI

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

Signed-off-by Stefan Binding <[email protected]>

---
 drivers/acpi/utils.c | 38 ++++++++++++++++++++++++++++++++++++++
 include/linux/acpi.h |  6 ++++++
 2 files changed, 44 insertions(+)

drivers/acpi/utils.c +38 -0

index 3a9773a09e19..4ef9ee4ad0d8 100644
@@ -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;
+
+	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) {
+		if (strlen(obj->string.pointer) < ACPI_MAX_SUB_BUF_SIZE &&
+		    strlen(obj->string.pointer) > 0) {
+			sub = kstrdup(obj->string.pointer, GFP_KERNEL);
+			if (!sub)
+				sub = ERR_PTR(-ENOMEM);
+		} else {
+			acpi_handle_err(handle, "ACPI _SUB Length %d is Invalid\n",
+					strlen(obj->string.pointer));
+			sub = ERR_PTR(-EINVAL);
+		}
+	} else {
+		acpi_handle_warn(handle, "Warning ACPI _SUB did not return a string\n");
+		sub = ERR_PTR(-EINVAL);
+	}
+
+	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,

include/linux/acpi.h +6 -0

index 4f82a5bc6d98..968a187f14f0 100644
@@ -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)
 {

Signature · 1 line

2.25.1

kernel test robot

build bot

2022-06-27 23:32 UTC #2 lore raw

Re: [PATCH v3 1/2] ACPI: utils: Add api to read _SUB from ACPI

Thank you for the patch! Perhaps something to improve:

Hi Stefan,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on rafael-pm/linux-next]
[also build test WARNING on broonie-sound/for-next linus/master v5.19-rc4 next-20220627] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/intel-lab-lkp/linux/commits/Stefan-Binding/Read-_SUB-from-ACPI-to-be-able-to-identify-firmware/20220627-235448
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next
config: x86_64-defconfig (https://download.01.org/0day-ci/archive/20220628/[email protected]/config)
compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
reproduce (this is a W=1 build):
        # https://github.com/intel-lab-lkp/linux/commit/7dd124b65442fd6622e7df2949795f735d8356be
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Stefan-Binding/Read-_SUB-from-ACPI-to-be-able-to-identify-firmware/20220627-235448
        git checkout 7dd124b65442fd6622e7df2949795f735d8356be
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/acpi/

If you fix the issue, kindly add following tag where applicable

Reported-by kernel test robot <[email protected]>

All warnings (new ones prefixed by >>):

In file included from drivers/acpi/utils.c:17:
drivers/acpi/utils.c: In function 'acpi_get_subsystem_id':

>> drivers/acpi/utils.c:317:49: warning: format '%d' expects argument of type 'int', but argument 4 has type 'size_t' {aka 'long unsigned int'} [-Wformat=]
     317 |                         acpi_handle_err(handle, "ACPI _SUB Length %d is Invalid\n",
         |                                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     318 |                                         strlen(obj->string.pointer));
         |                                         ~~~~~~~~~~~~~~~~~~~~~~~~~~~
         |                                         |
         |                                         size_t {aka long unsigned int}
   include/linux/acpi.h:1172:46: note: in definition of macro 'acpi_handle_err'
    1172 |         acpi_handle_printk(KERN_ERR, handle, fmt, ##__VA_ARGS__)
         |                                              ^~~
   drivers/acpi/utils.c:317:68: note: format string is defined here
     317 |                         acpi_handle_err(handle, "ACPI _SUB Length %d is Invalid\n",
         |                                                                   ~^
         |                                                                    |
         |                                                                    int
         |                                                                   %ld

vim +317 drivers/acpi/utils.c

295
296 const char *acpi_get_subsystem_id(acpi_handle handle)
297 {
298 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
299 union acpi_object *obj;
300 acpi_status status;
301 const char *sub;
302
303 status = acpi_evaluate_object(handle, METHOD_NAME__SUB, NULL, &buffer);
304 if (ACPI_FAILURE(status)) {
305 acpi_handle_debug(handle, "Reading ACPI _SUB failed: %#x\n", status);
306 return ERR_PTR(-ENODATA);
307 }
308
309 obj = buffer.pointer;
310 if (obj->type == ACPI_TYPE_STRING) {
311 if (strlen(obj->string.pointer) < ACPI_MAX_SUB_BUF_SIZE &&
312 strlen(obj->string.pointer) > 0) {
313 sub = kstrdup(obj->string.pointer, GFP_KERNEL);
314 if (!sub)
315 sub = ERR_PTR(-ENOMEM);
316 } else {

 > 317				acpi_handle_err(handle, "ACPI _SUB Length %d is Invalid\n",

318 strlen(obj->string.pointer));
319 sub = ERR_PTR(-EINVAL);
320 }
321 } else {
322 acpi_handle_warn(handle, "Warning ACPI _SUB did not return a string\n");
323 sub = ERR_PTR(-EINVAL);
324 }
325
326 acpi_os_free(buffer.pointer);
327
328 return sub;
329 }
330 EXPORT_SYMBOL_GPL(acpi_get_subsystem_id);
331

Signature · 2 lines

0-DAY CI Kernel Test Service
https://01.org/lkp

kernel test robot

build bot

2022-06-28 00:13 UTC #3 lore raw

Re: [PATCH v3 1/2] ACPI: utils: Add api to read _SUB from ACPI

In reply to Stefan Binding

Thank you for the patch! Perhaps something to improve:

Hi Stefan,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on rafael-pm/linux-next]
[also build test WARNING on broonie-sound/for-next linus/master v5.19-rc4 next-20220627] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/intel-lab-lkp/linux/commits/Stefan-Binding/Read-_SUB-from-ACPI-to-be-able-to-identify-firmware/20220627-235448
base:   https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git linux-next
config: x86_64-rhel-8.3-syz (https://download.01.org/0day-ci/archive/20220628/[email protected]/config)
compiler: gcc-11 (Debian 11.3.0-3) 11.3.0
reproduce (this is a W=1 build):
        # https://github.com/intel-lab-lkp/linux/commit/7dd124b65442fd6622e7df2949795f735d8356be
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Stefan-Binding/Read-_SUB-from-ACPI-to-be-able-to-identify-firmware/20220627-235448
        git checkout 7dd124b65442fd6622e7df2949795f735d8356be
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/acpi/

If you fix the issue, kindly add following tag where applicable

Reported-by kernel test robot <[email protected]>

All warnings (new ones prefixed by >>):

In file included from drivers/acpi/utils.c:17:
drivers/acpi/utils.c: In function 'acpi_get_subsystem_id':

>> drivers/acpi/utils.c:317:49: warning: format '%d' expects argument of type 'int', but argument 4 has type '__kernel_size_t' {aka 'long unsigned int'} [-Wformat=]
     317 |                         acpi_handle_err(handle, "ACPI _SUB Length %d is Invalid\n",
         |                                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/acpi.h:1172:46: note: in definition of macro 'acpi_handle_err'
    1172 |         acpi_handle_printk(KERN_ERR, handle, fmt, ##__VA_ARGS__)
         |                                              ^~~
   drivers/acpi/utils.c:317:68: note: format string is defined here
     317 |                         acpi_handle_err(handle, "ACPI _SUB Length %d is Invalid\n",
         |                                                                   ~^
         |                                                                    |
         |                                                                    int
         |                                                                   %ld

vim +317 drivers/acpi/utils.c

295
296 const char *acpi_get_subsystem_id(acpi_handle handle)
297 {
298 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
299 union acpi_object *obj;
300 acpi_status status;
301 const char *sub;
302
303 status = acpi_evaluate_object(handle, METHOD_NAME__SUB, NULL, &buffer);
304 if (ACPI_FAILURE(status)) {
305 acpi_handle_debug(handle, "Reading ACPI _SUB failed: %#x\n", status);
306 return ERR_PTR(-ENODATA);
307 }
308
309 obj = buffer.pointer;
310 if (obj->type == ACPI_TYPE_STRING) {
311 if (strlen(obj->string.pointer) < ACPI_MAX_SUB_BUF_SIZE &&
312 strlen(obj->string.pointer) > 0) {
313 sub = kstrdup(obj->string.pointer, GFP_KERNEL);
314 if (!sub)
315 sub = ERR_PTR(-ENOMEM);
316 } else {

 > 317				acpi_handle_err(handle, "ACPI _SUB Length %d is Invalid\n",

318 strlen(obj->string.pointer));
319 sub = ERR_PTR(-EINVAL);
320 }
321 } else {
322 acpi_handle_warn(handle, "Warning ACPI _SUB did not return a string\n");
323 sub = ERR_PTR(-EINVAL);
324 }
325
326 acpi_os_free(buffer.pointer);
327
328 return sub;
329 }
330 EXPORT_SYMBOL_GPL(acpi_get_subsystem_id);
331

Signature · 2 lines

0-DAY CI Kernel Test Service
https://01.org/lkp

Stefan Binding

author

2022-06-27 15:52 UTC #4 lore raw

PATCH v3 2/2 ASoC: cs35l41: Read System Name from ACPI _SUB to identify firmware

In reply to Stefan Binding

When loading firmware, wm_adsp uses a number of parameters to determine the path of the firmware and tuning files to load. One of these parameters is system_name.
Add support in cs35l41 to read this system name from the ACPI _SUB ID in order to uniquely identify the firmware and tuning mapped to a particular system.

Signed-off-by Stefan Binding <[email protected]>

---
 sound/soc/codecs/cs35l41.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

sound/soc/codecs/cs35l41.c +24 -0

index 8766e19d85f1..9ab016094b32 100644
@@ -6,6 +6,7 @@
 //
 // Author: David Rhodes <[email protected]>
 
+#include <linux/acpi.h>
 #include <linux/delay.h>
 #include <linux/err.h>
 #include <linux/init.h>

@@ -1142,6 +1143,24 @@ static int cs35l41_dsp_init(struct cs35l41_private *cs35l41)
 	return ret;
 }
 
+static int cs35l41_probe_acpi(struct cs35l41_private *cs35l41)
+{
+	acpi_handle handle = ACPI_HANDLE(cs35l41->dev);
+	const char *sub;
+
+	/* If there is no ACPI_HANDLE, there is no ACPI for this system, return 0 */
+	if (!handle)
+		return 0;
+
+	sub = acpi_get_subsystem_id(handle);
+	if (IS_ERR(sub))
+		return PTR_ERR(sub);
+
+	cs35l41->dsp.system_name = sub;
+	dev_dbg(cs35l41->dev, "Susystem ID: %s\n", cs35l41->dsp.system_name);
+	return 0;
+}
+
 int cs35l41_probe(struct cs35l41_private *cs35l41, const struct cs35l41_hw_cfg *hw_cfg)
 {
 	u32 regid, reg_revid, i, mtl_revid, int_status, chipid_match;

@@ -1270,6 +1289,10 @@ int cs35l41_probe(struct cs35l41_private *cs35l41, const struct cs35l41_hw_cfg *
 		goto err;
 	}
 
+	ret = cs35l41_probe_acpi(cs35l41);
+	if (ret < 0)
+		goto err;
+
 	ret = cs35l41_dsp_init(cs35l41);
 	if (ret < 0)
 		goto err;

@@ -1316,6 +1339,7 @@ void cs35l41_remove(struct cs35l41_private *cs35l41)
 	pm_runtime_disable(cs35l41->dev);
 
 	regmap_write(cs35l41->regmap, CS35L41_IRQ1_MASK1, 0xFFFFFFFF);
+	kfree(cs35l41->dsp.system_name);
 	wm_adsp2_remove(&cs35l41->dsp);
 	cs35l41_safe_reset(cs35l41->regmap, cs35l41->hw_cfg.bst_type);

Signature · 1 line

2.25.1