Re: [PATCH V5 1/2] firmware: add more flexible request_firmware_async function

[Luis R. Rodriguez]

On Thu, Aug 03, 2017 at 05:55:18AM +, Coelho, Luciano wrote:
> On Thu, 2017-08-03 at 08:23 +0300, Kalle Valo wrote:
> > "Luis R. Rodriguez"  writes:
> > 
> > > > +int request_firmware_nowait(struct module *module, bool uevent,
> > > > +   const char *name, struct device *device, 
> > > > gfp_t gfp,
> > > > +   void *context,
> > > > +   void (*cont)(const struct firmware *fw, 
> > > > void *context))
> > > > +{
> > > > +   unsigned int opt_flags = FW_OPT_FALLBACK |
> > > > +   (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
> > > > +
> > > > +   return __request_firmware_nowait(module, opt_flags, name, 
> > > > device, gfp,
> > > > +context, cont);
> > > > +}
> > > >  EXPORT_SYMBOL(request_firmware_nowait);
> > > >  
> > > > +int __request_firmware_async(struct module *module, const char *name,
> > > > +struct firmware_opts *fw_opts, struct 
> > > > device *dev,
> > > > +void *context,
> > > > +void (*cont)(const struct firmware *fw, 
> > > > void *context))
> > > > +{
> > > > +   unsigned int opt_flags = FW_OPT_UEVENT;
> > > 
> > > This exposes a long issue. Think -- why do we want this enabled by 
> > > default? Its
> > > actually because even though the fallback stuff is optional and can be, 
> > > the uevent
> > > internal flag *also* provides caching support as a side consequence only. 
> > > We
> > > don't want to add a new API without first cleaning up that mess.
> > > 
> > > This is a slipery slope and best to clean that up before adding any new 
> > > API.
> > > 
> > > That and also Greg recently stated he would like to see at least 3 users 
> > > of
> > > a feature before adding it. Although I think that's pretty arbitrary, and
> > > considering that request_firmware_into_buf() only has *one* user -- its 
> > > what
> > > he wishes.
> > 
> > ath10k at least needs a way to silence the warning for missing firmware
> > and I think iwlwifi also.
> 
> Yes, iwlwifi needs to silence the warning.  It the feature (only one,
> really) that I've been waiting for.

Luca,

can you confirm? The API revision thing is one thing but as I noted to
Kalle that can be done using a different API scheme as I had proposed on
the driver data API.

Other than that are there specific firmware requests which are async which
are not API revision style (min...max) for which an async request is optional?

 Luis

Re: [PATCH V5 1/2] firmware: add more flexible request_firmware_async function

[Luis R. Rodriguez]

On Thu, Aug 03, 2017 at 08:23:00AM +0300, Kalle Valo wrote:
> "Luis R. Rodriguez"  writes:
> 
> >> +int request_firmware_nowait(struct module *module, bool uevent,
> >> +  const char *name, struct device *device, gfp_t gfp,
> >> +  void *context,
> >> +  void (*cont)(const struct firmware *fw, void 
> >> *context))
> >> +{
> >> +  unsigned int opt_flags = FW_OPT_FALLBACK |
> >> +  (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
> >> +
> >> +  return __request_firmware_nowait(module, opt_flags, name, device, gfp,
> >> +   context, cont);
> >> +}
> >>  EXPORT_SYMBOL(request_firmware_nowait);
> >>  
> >> +int __request_firmware_async(struct module *module, const char *name,
> >> +   struct firmware_opts *fw_opts, struct device *dev,
> >> +   void *context,
> >> +   void (*cont)(const struct firmware *fw, void 
> >> *context))
> >> +{
> >> +  unsigned int opt_flags = FW_OPT_UEVENT;
> >
> > This exposes a long issue. Think -- why do we want this enabled by default? 
> > Its
> > actually because even though the fallback stuff is optional and can be, the 
> > uevent
> > internal flag *also* provides caching support as a side consequence only. We
> > don't want to add a new API without first cleaning up that mess.
> >
> > This is a slipery slope and best to clean that up before adding any new API.
> >
> > That and also Greg recently stated he would like to see at least 3 users of
> > a feature before adding it. Although I think that's pretty arbitrary, and
> > considering that request_firmware_into_buf() only has *one* user -- its what
> > he wishes.
> 
> ath10k at least needs a way to silence the warning for missing firmware
> and I think iwlwifi also.

It would seem ath10k actually does not need an async version of the no-warn
thing proposed here.

Below an analysis of how ath10k uses the firmware API. Note that I think
that iwlwifi may be on the same boat but the case and issue is slightly
different: both drivers use an API revision scheme, intermediate files
which are not found are not fatal as revisions go from min..max and only
one file is needed. A warning may be needed only if *no* file is found
at all.

I had proposed a new API call to handle this in the driver API series but
had only converted iwlwifi. It would seem ath10k can also be converted to
it and also they could end up sharing the same revision loop scheme so
less code on both drivers.

Below my analysis of how ath10k uses the firmware API:

You noted in private that ath10k long ago addressed the warning issue by
switching to request_firmware_direct() entirely:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9f5bcfe93315d75da4cc46bd30b536966559359a

Below is a list of the file name schemes used for all the different firmwares
types used in ath10k:

1)
/* pre-cal--.bin */
scnprintf(filename, sizeof(filename), "pre-cal-%s-%s.bin", 

2)

/* cal--.bin */
scnprintf(filename, sizeof(filename), "cal-%s-%s.bin",  
  ath10k_bus_str(ar->hif.bus), dev_name(ar->dev)); 


This seems fine as-is if indeed they are optional.

3) ath10k_core_fetch_board_data_api_1():

ar->hw_params.fw.dir/ar->hw_params.fw.board

This seems fine if indeed its optional.

3) Then you have a board file on ath10k_core_fetch_board_data_api_n():

boardname/ATH10K_BOARD_API2_FILE

This seems fine if indeed its optional.

4) Finally you have the actual firmware files which use a revision scheme
in ath10k_core_fetch_firmware_api_n():

for (i = ATH10K_FW_API_MAX; i >= ATH10K_FW_API_MIN; i--) {  
ar->fw_api = i; 
ath10k_dbg(ar, ATH10K_DBG_BOOT, "trying fw api %d\n",   
   ar->fw_api); 

ath10k_core_get_fw_name(ar, fw_name, sizeof(fw_name), 
ar->fw_api);
ret = ath10k_core_fetch_firmware_api_n(ar, fw_name, 
   
>normal_mode_fw.fw_file);
if (!ret)   
goto success;   
}

This ends up using the ar->hw_params.fw.dir/fw_name but fw_name is constructed
above using a API revision scheme. The fw_name can be of two types as per
ath10k_core_get_fw_name():

For SDIO:

scnprintf(fw_name, fw_name_len, "%s-%s-%d.bin", 
  ATH10K_FW_FILE_BASE, ath10k_bus_str(ar->hif.bus), 
  fw_api); 

Re: [PATCH V5 1/2] firmware: add more flexible request_firmware_async function

[Luis R. Rodriguez]

On Thu, Aug 03, 2017 at 05:55:18AM +, Coelho, Luciano wrote:
> On Thu, 2017-08-03 at 08:23 +0300, Kalle Valo wrote:
> > "Luis R. Rodriguez"  writes:
> > 
> > > > +int request_firmware_nowait(struct module *module, bool uevent,
> > > > +   const char *name, struct device *device, 
> > > > gfp_t gfp,
> > > > +   void *context,
> > > > +   void (*cont)(const struct firmware *fw, 
> > > > void *context))
> > > > +{
> > > > +   unsigned int opt_flags = FW_OPT_FALLBACK |
> > > > +   (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
> > > > +
> > > > +   return __request_firmware_nowait(module, opt_flags, name, 
> > > > device, gfp,
> > > > +context, cont);
> > > > +}
> > > >  EXPORT_SYMBOL(request_firmware_nowait);
> > > >  
> > > > +int __request_firmware_async(struct module *module, const char *name,
> > > > +struct firmware_opts *fw_opts, struct 
> > > > device *dev,
> > > > +void *context,
> > > > +void (*cont)(const struct firmware *fw, 
> > > > void *context))
> > > > +{
> > > > +   unsigned int opt_flags = FW_OPT_UEVENT;
> > > 
> > > This exposes a long issue. Think -- why do we want this enabled by 
> > > default? Its
> > > actually because even though the fallback stuff is optional and can be, 
> > > the uevent
> > > internal flag *also* provides caching support as a side consequence only. 
> > > We
> > > don't want to add a new API without first cleaning up that mess.
> > > 
> > > This is a slipery slope and best to clean that up before adding any new 
> > > API.
> > > 
> > > That and also Greg recently stated he would like to see at least 3 users 
> > > of
> > > a feature before adding it. Although I think that's pretty arbitrary, and
> > > considering that request_firmware_into_buf() only has *one* user -- its 
> > > what
> > > he wishes.
> > 
> > ath10k at least needs a way to silence the warning for missing firmware
> > and I think iwlwifi also.
> 
> Yes, iwlwifi needs to silence the warning.  It the feature (only one,
> really) that I've been waiting for.

Perfect, can you guys send patches on top of these changes? Even though I still
think the flag stuff needs to be worked out I can try to iron that out myself
and fold the rest of the delta, and then I can set a new set out which is much
more suitable.

  Luis

Re: [PATCH V5 1/2] firmware: add more flexible request_firmware_async function

[Coelho, Luciano]

On Thu, 2017-08-03 at 08:23 +0300, Kalle Valo wrote:
> "Luis R. Rodriguez"  writes:
> 
> > > +int request_firmware_nowait(struct module *module, bool uevent,
> > > + const char *name, struct device *device, gfp_t gfp,
> > > + void *context,
> > > + void (*cont)(const struct firmware *fw, void 
> > > *context))
> > > +{
> > > + unsigned int opt_flags = FW_OPT_FALLBACK |
> > > + (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
> > > +
> > > + return __request_firmware_nowait(module, opt_flags, name, device, gfp,
> > > +  context, cont);
> > > +}
> > >  EXPORT_SYMBOL(request_firmware_nowait);
> > >  
> > > +int __request_firmware_async(struct module *module, const char *name,
> > > +  struct firmware_opts *fw_opts, struct device *dev,
> > > +  void *context,
> > > +  void (*cont)(const struct firmware *fw, void 
> > > *context))
> > > +{
> > > + unsigned int opt_flags = FW_OPT_UEVENT;
> > 
> > This exposes a long issue. Think -- why do we want this enabled by default? 
> > Its
> > actually because even though the fallback stuff is optional and can be, the 
> > uevent
> > internal flag *also* provides caching support as a side consequence only. We
> > don't want to add a new API without first cleaning up that mess.
> > 
> > This is a slipery slope and best to clean that up before adding any new API.
> > 
> > That and also Greg recently stated he would like to see at least 3 users of
> > a feature before adding it. Although I think that's pretty arbitrary, and
> > considering that request_firmware_into_buf() only has *one* user -- its what
> > he wishes.
> 
> ath10k at least needs a way to silence the warning for missing firmware
> and I think iwlwifi also.

Yes, iwlwifi needs to silence the warning.  It the feature (only one,
really) that I've been waiting for.

--
Luca.

Re: [PATCH V5 1/2] firmware: add more flexible request_firmware_async function

[Kalle Valo]

"Luis R. Rodriguez"  writes:

>> +int request_firmware_nowait(struct module *module, bool uevent,
>> +const char *name, struct device *device, gfp_t gfp,
>> +void *context,
>> +void (*cont)(const struct firmware *fw, void 
>> *context))
>> +{
>> +unsigned int opt_flags = FW_OPT_FALLBACK |
>> +(uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
>> +
>> +return __request_firmware_nowait(module, opt_flags, name, device, gfp,
>> + context, cont);
>> +}
>>  EXPORT_SYMBOL(request_firmware_nowait);
>>  
>> +int __request_firmware_async(struct module *module, const char *name,
>> + struct firmware_opts *fw_opts, struct device *dev,
>> + void *context,
>> + void (*cont)(const struct firmware *fw, void 
>> *context))
>> +{
>> +unsigned int opt_flags = FW_OPT_UEVENT;
>
> This exposes a long issue. Think -- why do we want this enabled by default? 
> Its
> actually because even though the fallback stuff is optional and can be, the 
> uevent
> internal flag *also* provides caching support as a side consequence only. We
> don't want to add a new API without first cleaning up that mess.
>
> This is a slipery slope and best to clean that up before adding any new API.
>
> That and also Greg recently stated he would like to see at least 3 users of
> a feature before adding it. Although I think that's pretty arbitrary, and
> considering that request_firmware_into_buf() only has *one* user -- its what
> he wishes.

ath10k at least needs a way to silence the warning for missing firmware
and I think iwlwifi also.

-- 
Kalle Valo

Re: [PATCH V5 1/2] firmware: add more flexible request_firmware_async function

[Luis R. Rodriguez]

On Mon, Jul 31, 2017 at 05:09:44PM +0200, Rafał Miłecki wrote:
> From: Rafał Miłecki 
> 
> So far we got only one function for loading firmware asynchronously:
> request_firmware_nowait. It didn't allow much customization of firmware
> loading process - there is only one bool uevent argument. Moreover this
> bool also controls user helper in an unclear way.

> Some drivers need more flexible helper providing more options. This
> includes control over uevent or warning for the missing firmware. Of
> course this list may grow up in the future.
> 
> To handle this easily this patch adds a generic request_firmware_async
> function. It takes struct with options as an argument which will allow
> extending it in the future without massive changes.
> 
> This is a really cheap change (no new independent API) which works
> nicely with the existing code. The old request_firmware_nowait is kept
> as a simple helper calling new helper.
> 
> Signed-off-by: Rafał Miłecki 
> ---
> V3: Don't expose all FW_OPT_* flags.
> As Luis noted we want a struct so add struct firmware_opts for real
> flexibility.
> Thank you Luis for your review!
> V5: Rebase, update commit message, resend after drvdata discussion
> ---
>  drivers/base/firmware_class.c | 43 
> ++-
>  include/linux/firmware.h  | 15 ++-
>  2 files changed, 48 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
> index b9f907eedbf7..cde85b05e4cb 100644
> --- a/drivers/base/firmware_class.c
> +++ b/drivers/base/firmware_class.c
> @@ -1375,7 +1375,7 @@ static void request_firmware_work_func(struct 
> work_struct *work)
>   _request_firmware(, fw_work->name, fw_work->device, NULL, 0,
> fw_work->opt_flags);
>   fw_work->cont(fw, fw_work->context);
> - put_device(fw_work->device); /* taken in request_firmware_nowait() */
> + put_device(fw_work->device); /* taken in __request_firmware_nowait() */
>  
>   module_put(fw_work->module);
>   kfree_const(fw_work->name);
> @@ -1383,10 +1383,9 @@ static void request_firmware_work_func(struct 
> work_struct *work)
>  }
>  
>  /**
> - * request_firmware_nowait - asynchronous version of request_firmware
> + * __request_firmware_nowait - asynchronous version of request_firmware
>   * @module: module requesting the firmware
> - * @uevent: sends uevent to copy the firmware image if this flag
> - *   is non-zero else the firmware copy must be done manually.
> + * @opt_flags: flags that control firmware loading process, see FW_OPT_*
>   * @name: name of firmware file
>   * @device: device for which firmware is being loaded
>   * @gfp: allocation flags
> @@ -1405,9 +1404,9 @@ static void request_firmware_work_func(struct 
> work_struct *work)
>   *
>   *   - can't sleep at all if @gfp is GFP_ATOMIC.
>   **/
> -int
> -request_firmware_nowait(
> - struct module *module, bool uevent,
> +static int
> +__request_firmware_nowait(
> + struct module *module, unsigned int opt_flags,
>   const char *name, struct device *device, gfp_t gfp, void *context,
>   void (*cont)(const struct firmware *fw, void *context))
>  {
> @@ -1426,8 +1425,7 @@ request_firmware_nowait(
>   fw_work->device = device;
>   fw_work->context = context;
>   fw_work->cont = cont;
> - fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
> - (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
> + fw_work->opt_flags = FW_OPT_NOWAIT | opt_flags;
>  
>   if (!try_module_get(module)) {
>   kfree_const(fw_work->name);
> @@ -1440,8 +1438,35 @@ request_firmware_nowait(
>   schedule_work(_work->work);
>   return 0;
>  }
> +
> +int request_firmware_nowait(struct module *module, bool uevent,
> + const char *name, struct device *device, gfp_t gfp,
> + void *context,
> + void (*cont)(const struct firmware *fw, void 
> *context))
> +{
> + unsigned int opt_flags = FW_OPT_FALLBACK |
> + (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
> +
> + return __request_firmware_nowait(module, opt_flags, name, device, gfp,
> +  context, cont);
> +}
>  EXPORT_SYMBOL(request_firmware_nowait);
>  
> +int __request_firmware_async(struct module *module, const char *name,
> +  struct firmware_opts *fw_opts, struct device *dev,
> +  void *context,
> +  void (*cont)(const struct firmware *fw, void 
> *context))
> +{
> + unsigned int opt_flags = FW_OPT_UEVENT;

This exposes a long issue. Think -- why do we want this enabled by default? Its
actually because even though the fallback stuff is optional and can be, the 
uevent
internal flag *also* provides caching support as a side consequence only. We
don't want to add a new API without first 

Re: [PATCH V5 1/2] firmware: add more flexible request_firmware_async function

[kbuild test robot]

Hi Rafał,

[auto build test WARNING on driver-core/driver-core-testing]
[also build test WARNING on v4.13-rc3 next-20170731]
[if your patch is applied to the wrong git tree, please drop us a note to help 
improve the system]

url:
https://github.com/0day-ci/linux/commits/Rafa-Mi-ecki/firmware-add-more-flexible-request_firmware_async-function/20170801-033319
reproduce: make htmldocs

All warnings (new ones prefixed by >>):

   WARNING: convert(1) not found, for SVG to PDF conversion install ImageMagick 
(https://www.imagemagick.org)
   include/linux/init.h:1: warning: no structured comments found
   include/linux/mod_devicetable.h:687: warning: Excess 
struct/union/enum/typedef member 'ver_major' description in 'fsl_mc_device_id'
   include/linux/mod_devicetable.h:687: warning: Excess 
struct/union/enum/typedef member 'ver_minor' description in 'fsl_mc_device_id'
   kernel/sched/core.c:2080: warning: No description found for parameter 'rf'
   kernel/sched/core.c:2080: warning: Excess function parameter 'cookie' 
description in 'try_to_wake_up_local'
   include/linux/wait.h:555: warning: No description found for parameter 'wq'
   include/linux/wait.h:555: warning: Excess function parameter 'wq_head' 
description in 'wait_event_interruptible_hrtimeout'
   include/linux/wait.h:759: warning: No description found for parameter 
'wq_head'
   include/linux/wait.h:759: warning: Excess function parameter 'wq' 
description in 'wait_event_killable'
   include/linux/kthread.h:26: warning: Excess function parameter '...' 
description in 'kthread_create'
   kernel/sys.c:1: warning: no structured comments found
   include/linux/device.h:968: warning: No description found for parameter 
'dma_ops'
   drivers/dma-buf/seqno-fence.c:1: warning: no structured comments found
>> drivers/base/firmware_class.c:1: warning: no structured comments found
   include/linux/iio/iio.h:603: warning: No description found for parameter 
'trig_readonly'
   include/linux/iio/trigger.h:151: warning: No description found for parameter 
'indio_dev'
   include/linux/iio/trigger.h:151: warning: No description found for parameter 
'trig'
   include/linux/device.h:969: warning: No description found for parameter 
'dma_ops'
   drivers/ata/libata-eh.c:1449: warning: No description found for parameter 
'link'
   drivers/ata/libata-eh.c:1449: warning: Excess function parameter 'ap' 
description in 'ata_eh_done'
   drivers/ata/libata-eh.c:1590: warning: No description found for parameter 
'qc'
   drivers/ata/libata-eh.c:1590: warning: Excess function parameter 'dev' 
description in 'ata_eh_request_sense'
   drivers/mtd/nand/nand_base.c:2751: warning: Excess function parameter 
'cached' description in 'nand_write_page'
   drivers/mtd/nand/nand_base.c:2751: warning: Excess function parameter 
'cached' description in 'nand_write_page'
   arch/s390/include/asm/cmb.h:1: warning: no structured comments found
   drivers/scsi/scsi_lib.c:1116: warning: No description found for parameter 
'rq'
   drivers/scsi/constants.c:1: warning: no structured comments found
   include/linux/usb/gadget.h:230: warning: No description found for parameter 
'claimed'
   include/linux/usb/gadget.h:230: warning: No description found for parameter 
'enabled'
   include/linux/usb/gadget.h:412: warning: No description found for parameter 
'quirk_altset_not_supp'
   include/linux/usb/gadget.h:412: warning: No description found for parameter 
'quirk_stall_not_supp'
   include/linux/usb/gadget.h:412: warning: No description found for parameter 
'quirk_zlp_not_supp'
   fs/inode.c:1666: warning: No description found for parameter 'rcu'
   include/linux/jbd2.h:443: warning: No description found for parameter 
'i_transaction'
   include/linux/jbd2.h:443: warning: No description found for parameter 
'i_next_transaction'
   include/linux/jbd2.h:443: warning: No description found for parameter 
'i_list'
   include/linux/jbd2.h:443: warning: No description found for parameter 
'i_vfs_inode'
   include/linux/jbd2.h:443: warning: No description found for parameter 
'i_flags'
   include/linux/jbd2.h:497: warning: No description found for parameter 
'h_rsv_handle'
   include/linux/jbd2.h:497: warning: No description found for parameter 
'h_reserved'
   include/linux/jbd2.h:497: warning: No description found for parameter 
'h_type'
   include/linux/jbd2.h:497: warning: No description found for parameter 
'h_line_no'
   include/linux/jbd2.h:497: warning: No description found for parameter 
'h_start_jiffies'
   include/linux/jbd2.h:497: warning: No description found for parameter 
'h_requested_credits'
   include/linux/jbd2.h:497: warning: No description found for parameter 
'saved_alloc_context'
   include/linux/jbd2.h:1050: warning: No description found for parameter 
'j_chkpt_bhs'
   include/linux/jbd2.h:1050: warning: No description found for parameter 
'j_devname'
   include/linux/jbd2.h:1050: warning: No description found for parameter 
'j_average_commit_time'
   include/linux/jbd2.h:1050: 

[PATCH V5 1/2] firmware: add more flexible request_firmware_async function

[Rafał Miłecki]

From: Rafał Miłecki 

So far we got only one function for loading firmware asynchronously:
request_firmware_nowait. It didn't allow much customization of firmware
loading process - there is only one bool uevent argument. Moreover this
bool also controls user helper in an unclear way.

Some drivers need more flexible helper providing more options. This
includes control over uevent or warning for the missing firmware. Of
course this list may grow up in the future.

To handle this easily this patch adds a generic request_firmware_async
function. It takes struct with options as an argument which will allow
extending it in the future without massive changes.

This is a really cheap change (no new independent API) which works
nicely with the existing code. The old request_firmware_nowait is kept
as a simple helper calling new helper.

Signed-off-by: Rafał Miłecki 
---
V3: Don't expose all FW_OPT_* flags.
As Luis noted we want a struct so add struct firmware_opts for real
flexibility.
Thank you Luis for your review!
V5: Rebase, update commit message, resend after drvdata discussion
---
 drivers/base/firmware_class.c | 43 ++-
 include/linux/firmware.h  | 15 ++-
 2 files changed, 48 insertions(+), 10 deletions(-)

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index b9f907eedbf7..cde85b05e4cb 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -1375,7 +1375,7 @@ static void request_firmware_work_func(struct work_struct 
*work)
_request_firmware(, fw_work->name, fw_work->device, NULL, 0,
  fw_work->opt_flags);
fw_work->cont(fw, fw_work->context);
-   put_device(fw_work->device); /* taken in request_firmware_nowait() */
+   put_device(fw_work->device); /* taken in __request_firmware_nowait() */
 
module_put(fw_work->module);
kfree_const(fw_work->name);
@@ -1383,10 +1383,9 @@ static void request_firmware_work_func(struct 
work_struct *work)
 }
 
 /**
- * request_firmware_nowait - asynchronous version of request_firmware
+ * __request_firmware_nowait - asynchronous version of request_firmware
  * @module: module requesting the firmware
- * @uevent: sends uevent to copy the firmware image if this flag
- * is non-zero else the firmware copy must be done manually.
+ * @opt_flags: flags that control firmware loading process, see FW_OPT_*
  * @name: name of firmware file
  * @device: device for which firmware is being loaded
  * @gfp: allocation flags
@@ -1405,9 +1404,9 @@ static void request_firmware_work_func(struct work_struct 
*work)
  *
  * - can't sleep at all if @gfp is GFP_ATOMIC.
  **/
-int
-request_firmware_nowait(
-   struct module *module, bool uevent,
+static int
+__request_firmware_nowait(
+   struct module *module, unsigned int opt_flags,
const char *name, struct device *device, gfp_t gfp, void *context,
void (*cont)(const struct firmware *fw, void *context))
 {
@@ -1426,8 +1425,7 @@ request_firmware_nowait(
fw_work->device = device;
fw_work->context = context;
fw_work->cont = cont;
-   fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
-   (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
+   fw_work->opt_flags = FW_OPT_NOWAIT | opt_flags;
 
if (!try_module_get(module)) {
kfree_const(fw_work->name);
@@ -1440,8 +1438,35 @@ request_firmware_nowait(
schedule_work(_work->work);
return 0;
 }
+
+int request_firmware_nowait(struct module *module, bool uevent,
+   const char *name, struct device *device, gfp_t gfp,
+   void *context,
+   void (*cont)(const struct firmware *fw, void 
*context))
+{
+   unsigned int opt_flags = FW_OPT_FALLBACK |
+   (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
+
+   return __request_firmware_nowait(module, opt_flags, name, device, gfp,
+context, cont);
+}
 EXPORT_SYMBOL(request_firmware_nowait);
 
+int __request_firmware_async(struct module *module, const char *name,
+struct firmware_opts *fw_opts, struct device *dev,
+void *context,
+void (*cont)(const struct firmware *fw, void 
*context))
+{
+   unsigned int opt_flags = FW_OPT_UEVENT;
+
+   if (fw_opts->optional)
+   opt_flags |= FW_OPT_NO_WARN;
+
+   return __request_firmware_nowait(module, opt_flags, name, dev,
+GFP_KERNEL, context, cont);
+}
+EXPORT_SYMBOL(__request_firmware_async);
+
 #ifdef CONFIG_PM_SLEEP
 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
 
diff --git a/include/linux/firmware.h b/include/linux/firmware.h
index b1f9f0ccb8ac..a32b6e67462d 100644
--- a/include/linux/firmware.h
+++