diff mbox series

[v6,4/5] wifi: brcmfmac: Add optional lpo clock enable support

Message ID 20240731061132.703368-5-jacobe.zang@wesion.com (mailing list archive)
State New, archived
Headers show
Series Add AP6275P wireless support | expand

Commit Message

Jacobe Zang July 31, 2024, 6:11 a.m. UTC
WiFi modules often require 32kHz clock to function. Add support to
enable the clock to PCIe driver and move "brcm,bcm4329-fmac" check
to the top of brcmf_of_probe

Co-developed-by: Ondrej Jirman <megi@xff.cz>
Signed-off-by: Ondrej Jirman <megi@xff.cz>
Signed-off-by: Jacobe Zang <jacobe.zang@wesion.com>
---
 .../net/wireless/broadcom/brcm80211/brcmfmac/of.c    | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

Comments

Alexey Charkov July 31, 2024, 10:16 a.m. UTC | #1
Hi Jacobe,


On 31/07/2024 9:11 am, Jacobe Zang wrote:
 > WiFi modules often require 32kHz clock to function. Add support to
 > enable the clock to PCIe driver and move "brcm,bcm4329-fmac" check
 > to the top of brcmf_of_probe
 >
 > Co-developed-by: Ondrej Jirman <megi@xff.cz>
 > Signed-off-by: Ondrej Jirman <megi@xff.cz>
 > Signed-off-by: Jacobe Zang <jacobe.zang@wesion.com>
 > ---
 >  .../net/wireless/broadcom/brcm80211/brcmfmac/of.c    | 12 +++++++++++-
 >  1 file changed, 11 insertions(+), 1 deletion(-)
 >
 > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c 
b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
 > index e406e11481a62..7e0a2ad5c7c8a 100644
 > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
 > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
 > @@ -6,6 +6,7 @@
 >  #include <linux/of.h>
 >  #include <linux/of_irq.h>
 >  #include <linux/of_net.h>
 > +#include <linux/clk.h>
 >
 >  #include <defs.h>
 >  #include "debug.h"
 > @@ -70,12 +71,16 @@ void brcmf_of_probe(struct device *dev, enum 
brcmf_bus_type bus_type,
 >  {
 >      struct brcmfmac_sdio_pd *sdio = &settings->bus.sdio;
 >      struct device_node *root, *np = dev->of_node;
 > +    struct clk *clk;
 >      const char *prop;
 >      int irq;
 >      int err;
 >      u32 irqf;
 >      u32 val;
 >
 > +    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
 > +        return;

Did you test this? The DTS patch you sent as part of this series doesn't 
list "brcm,bcm4329-fmac" in the compatible, so this will probably return 
right here, skipping over the rest of your patch.

Please test before resending, both with and without the driver for the 
Bluetooth part of the chip (since it also touches clocks).

You are also changing the behavior for other systems by putting this 
check further up the probe path, which might break things for no reason. 
Better put your clk-related addition below where this check was 
originally, rather than reorder stuff you don't have to reorder.

 > +
 >      /* Apple ARM64 platforms have their own idea of board type, 
passed in
 >       * via the device tree. They also have an antenna SKU parameter
 >       */
 > @@ -113,8 +118,13 @@ void brcmf_of_probe(struct device *dev, enum 
brcmf_bus_type bus_type,
 >          of_node_put(root);
 >      }
 >
 > -    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
 > +    clk = devm_clk_get_optional_enabled(dev, "lpo");
 > +    if (!IS_ERR_OR_NULL(clk)) {
 > +        brcmf_dbg(INFO, "enabling 32kHz clock\n");
 > +        clk_set_rate(clk, 32768);
 > +    } else {
 >          return;

Why return here? If the clock is optional, a lot of systems will not 
have it - that shouldn't prevent the driver from probing. And you are 
still not handling the -EPROBE_DEFER case which was mentioned on your 
previous submission.

Best regards,
Alexey
Arend van Spriel July 31, 2024, 11:14 a.m. UTC | #2
On 7/31/2024 12:16 PM, Alexey Charkov wrote:
> Hi Jacobe,
> 
> 
> On 31/07/2024 9:11 am, Jacobe Zang wrote:
>  > WiFi modules often require 32kHz clock to function. Add support to
>  > enable the clock to PCIe driver and move "brcm,bcm4329-fmac" check
>  > to the top of brcmf_of_probe
>  >
>  > Co-developed-by: Ondrej Jirman <megi@xff.cz>
>  > Signed-off-by: Ondrej Jirman <megi@xff.cz>
>  > Signed-off-by: Jacobe Zang <jacobe.zang@wesion.com>
>  > ---
>  >  .../net/wireless/broadcom/brcm80211/brcmfmac/of.c    | 12 +++++++++++-
>  >  1 file changed, 11 insertions(+), 1 deletion(-)
>  >
>  > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c 
> b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
>  > index e406e11481a62..7e0a2ad5c7c8a 100644
>  > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
>  > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
>  > @@ -6,6 +6,7 @@
>  >  #include <linux/of.h>
>  >  #include <linux/of_irq.h>
>  >  #include <linux/of_net.h>
>  > +#include <linux/clk.h>
>  >
>  >  #include <defs.h>
>  >  #include "debug.h"
>  > @@ -70,12 +71,16 @@ void brcmf_of_probe(struct device *dev, enum 
> brcmf_bus_type bus_type,
>  >  {
>  >      struct brcmfmac_sdio_pd *sdio = &settings->bus.sdio;
>  >      struct device_node *root, *np = dev->of_node;
>  > +    struct clk *clk;
>  >      const char *prop;
>  >      int irq;
>  >      int err;
>  >      u32 irqf;
>  >      u32 val;
>  >
>  > +    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
>  > +        return;
> 
> Did you test this? The DTS patch you sent as part of this series doesn't 
> list "brcm,bcm4329-fmac" in the compatible, so this will probably return 
> right here, skipping over the rest of your patch.
> 
> Please test before resending, both with and without the driver for the 
> Bluetooth part of the chip (since it also touches clocks).
> 
> You are also changing the behavior for other systems by putting this 
> check further up the probe path, which might break things for no reason. 
> Better put your clk-related addition below where this check was 
> originally, rather than reorder stuff you don't have to reorder.

That was upon my suggestion. That check was originally at the top of the 
function, but people added stuff before that. I agree that makes the 
compatible "brcm,brcm4329-fmac" required which is what the textual 
binding stated before the switch to YAML was made:

"""
Broadcom BCM43xx Fullmac wireless SDIO devices

This node provides properties for controlling the Broadcom wireless 
device. The
node is expected to be specified as a child node to the SDIO controller that
connects the device to the system.

Required properties:

  - compatible : Should be "brcm,bcm4329-fmac".
"""

Not sure whether this is still true for YAML version (poor YAML reading 
skills ;-) ), but it should as the switch from textual to YAML should 
not have changed the bindings specification.

>  > +
>  >      /* Apple ARM64 platforms have their own idea of board type, 
> passed in
>  >       * via the device tree. They also have an antenna SKU parameter
>  >       */
>  > @@ -113,8 +118,13 @@ void brcmf_of_probe(struct device *dev, enum 
> brcmf_bus_type bus_type,
>  >          of_node_put(root);
>  >      }
>  >
>  > -    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
>  > +    clk = devm_clk_get_optional_enabled(dev, "lpo");
>  > +    if (!IS_ERR_OR_NULL(clk)) {
>  > +        brcmf_dbg(INFO, "enabling 32kHz clock\n");
>  > +        clk_set_rate(clk, 32768);
>  > +    } else {
>  >          return;
> 
> Why return here? If the clock is optional, a lot of systems will not 
> have it - that shouldn't prevent the driver from probing. And you are 
> still not handling the -EPROBE_DEFER case which was mentioned on your 
> previous submission.

Right. The else statement above could/should be:

} else if (clk && PTR_ERR(clk) == -EPROBE_DEFER) {
         return PTR_ERR(clk);
}

Regards,
Arend
Alexey Charkov July 31, 2024, 12:01 p.m. UTC | #3
On Wed, Jul 31, 2024 at 2:15 PM Arend van Spriel
<arend.vanspriel@broadcom.com> wrote:
>
> On 7/31/2024 12:16 PM, Alexey Charkov wrote:
> > Hi Jacobe,
> >
> >
> > On 31/07/2024 9:11 am, Jacobe Zang wrote:
> >  > WiFi modules often require 32kHz clock to function. Add support to
> >  > enable the clock to PCIe driver and move "brcm,bcm4329-fmac" check
> >  > to the top of brcmf_of_probe
> >  >
> >  > Co-developed-by: Ondrej Jirman <megi@xff.cz>
> >  > Signed-off-by: Ondrej Jirman <megi@xff.cz>
> >  > Signed-off-by: Jacobe Zang <jacobe.zang@wesion.com>
> >  > ---
> >  >  .../net/wireless/broadcom/brcm80211/brcmfmac/of.c    | 12 +++++++++++-
> >  >  1 file changed, 11 insertions(+), 1 deletion(-)
> >  >
> >  > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> > b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> >  > index e406e11481a62..7e0a2ad5c7c8a 100644
> >  > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> >  > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> >  > @@ -6,6 +6,7 @@
> >  >  #include <linux/of.h>
> >  >  #include <linux/of_irq.h>
> >  >  #include <linux/of_net.h>
> >  > +#include <linux/clk.h>
> >  >
> >  >  #include <defs.h>
> >  >  #include "debug.h"
> >  > @@ -70,12 +71,16 @@ void brcmf_of_probe(struct device *dev, enum
> > brcmf_bus_type bus_type,
> >  >  {
> >  >      struct brcmfmac_sdio_pd *sdio = &settings->bus.sdio;
> >  >      struct device_node *root, *np = dev->of_node;
> >  > +    struct clk *clk;
> >  >      const char *prop;
> >  >      int irq;
> >  >      int err;
> >  >      u32 irqf;
> >  >      u32 val;
> >  >
> >  > +    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
> >  > +        return;
> >
> > Did you test this? The DTS patch you sent as part of this series doesn't
> > list "brcm,bcm4329-fmac" in the compatible, so this will probably return
> > right here, skipping over the rest of your patch.
> >
> > Please test before resending, both with and without the driver for the
> > Bluetooth part of the chip (since it also touches clocks).
> >
> > You are also changing the behavior for other systems by putting this
> > check further up the probe path, which might break things for no reason.
> > Better put your clk-related addition below where this check was
> > originally, rather than reorder stuff you don't have to reorder.
>
> That was upon my suggestion. That check was originally at the top of the
> function, but people added stuff before that. I agree that makes the
> compatible "brcm,brcm4329-fmac" required which is what the textual
> binding stated before the switch to YAML was made:
>
> """
> Broadcom BCM43xx Fullmac wireless SDIO devices
>
> This node provides properties for controlling the Broadcom wireless
> device. The
> node is expected to be specified as a child node to the SDIO controller that
> connects the device to the system.
>
> Required properties:
>
>   - compatible : Should be "brcm,bcm4329-fmac".
> """
>
> Not sure whether this is still true for YAML version (poor YAML reading
> skills ;-) ), but it should as the switch from textual to YAML should
> not have changed the bindings specification.
>
> >  > +
> >  >      /* Apple ARM64 platforms have their own idea of board type,
> > passed in
> >  >       * via the device tree. They also have an antenna SKU parameter
> >  >       */
> >  > @@ -113,8 +118,13 @@ void brcmf_of_probe(struct device *dev, enum
> > brcmf_bus_type bus_type,
> >  >          of_node_put(root);
> >  >      }
> >  >
> >  > -    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
> >  > +    clk = devm_clk_get_optional_enabled(dev, "lpo");
> >  > +    if (!IS_ERR_OR_NULL(clk)) {
> >  > +        brcmf_dbg(INFO, "enabling 32kHz clock\n");
> >  > +        clk_set_rate(clk, 32768);
> >  > +    } else {
> >  >          return;
> >
> > Why return here? If the clock is optional, a lot of systems will not
> > have it - that shouldn't prevent the driver from probing. And you are
> > still not handling the -EPROBE_DEFER case which was mentioned on your
> > previous submission.
>
> Right. The else statement above could/should be:
>
> } else if (clk && PTR_ERR(clk) == -EPROBE_DEFER) {
>          return PTR_ERR(clk);
> }

... plus change the function prototype to return int and propagate
that error code through brcmf_get_module_param to brcmf_pcie_probe's
return value. I guess checking clk for NULL is also redundant in this
case?

Best,
Alexey
Arend van Spriel July 31, 2024, 12:32 p.m. UTC | #4
On 7/31/2024 2:01 PM, Alexey Charkov wrote:
> On Wed, Jul 31, 2024 at 2:15 PM Arend van Spriel
> <arend.vanspriel@broadcom.com> wrote:
>>
>> On 7/31/2024 12:16 PM, Alexey Charkov wrote:
>>> Hi Jacobe,
>>>
>>>
>>> On 31/07/2024 9:11 am, Jacobe Zang wrote:
>>>   > WiFi modules often require 32kHz clock to function. Add support to
>>>   > enable the clock to PCIe driver and move "brcm,bcm4329-fmac" check
>>>   > to the top of brcmf_of_probe
>>>   >
>>>   > Co-developed-by: Ondrej Jirman <megi@xff.cz>
>>>   > Signed-off-by: Ondrej Jirman <megi@xff.cz>
>>>   > Signed-off-by: Jacobe Zang <jacobe.zang@wesion.com>
>>>   > ---
>>>   >  .../net/wireless/broadcom/brcm80211/brcmfmac/of.c    | 12 +++++++++++-
>>>   >  1 file changed, 11 insertions(+), 1 deletion(-)
>>>   >
>>>   > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
>>> b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
>>>   > index e406e11481a62..7e0a2ad5c7c8a 100644
>>>   > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
>>>   > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
>>>   > @@ -6,6 +6,7 @@
>>>   >  #include <linux/of.h>
>>>   >  #include <linux/of_irq.h>
>>>   >  #include <linux/of_net.h>
>>>   > +#include <linux/clk.h>
>>>   >
>>>   >  #include <defs.h>
>>>   >  #include "debug.h"
>>>   > @@ -70,12 +71,16 @@ void brcmf_of_probe(struct device *dev, enum
>>> brcmf_bus_type bus_type,
>>>   >  {
>>>   >      struct brcmfmac_sdio_pd *sdio = &settings->bus.sdio;
>>>   >      struct device_node *root, *np = dev->of_node;
>>>   > +    struct clk *clk;
>>>   >      const char *prop;
>>>   >      int irq;
>>>   >      int err;
>>>   >      u32 irqf;
>>>   >      u32 val;
>>>   >
>>>   > +    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
>>>   > +        return;
>>>
>>> Did you test this? The DTS patch you sent as part of this series doesn't
>>> list "brcm,bcm4329-fmac" in the compatible, so this will probably return
>>> right here, skipping over the rest of your patch.
>>>
>>> Please test before resending, both with and without the driver for the
>>> Bluetooth part of the chip (since it also touches clocks).
>>>
>>> You are also changing the behavior for other systems by putting this
>>> check further up the probe path, which might break things for no reason.
>>> Better put your clk-related addition below where this check was
>>> originally, rather than reorder stuff you don't have to reorder.
>>
>> That was upon my suggestion. That check was originally at the top of the
>> function, but people added stuff before that. I agree that makes the
>> compatible "brcm,brcm4329-fmac" required which is what the textual
>> binding stated before the switch to YAML was made:
>>
>> """
>> Broadcom BCM43xx Fullmac wireless SDIO devices
>>
>> This node provides properties for controlling the Broadcom wireless
>> device. The
>> node is expected to be specified as a child node to the SDIO controller that
>> connects the device to the system.
>>
>> Required properties:
>>
>>    - compatible : Should be "brcm,bcm4329-fmac".
>> """
>>
>> Not sure whether this is still true for YAML version (poor YAML reading
>> skills ;-) ), but it should as the switch from textual to YAML should
>> not have changed the bindings specification.
>>
>>>   > +
>>>   >      /* Apple ARM64 platforms have their own idea of board type,
>>> passed in
>>>   >       * via the device tree. They also have an antenna SKU parameter
>>>   >       */
>>>   > @@ -113,8 +118,13 @@ void brcmf_of_probe(struct device *dev, enum
>>> brcmf_bus_type bus_type,
>>>   >          of_node_put(root);
>>>   >      }
>>>   >
>>>   > -    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
>>>   > +    clk = devm_clk_get_optional_enabled(dev, "lpo");
>>>   > +    if (!IS_ERR_OR_NULL(clk)) {
>>>   > +        brcmf_dbg(INFO, "enabling 32kHz clock\n");
>>>   > +        clk_set_rate(clk, 32768);
>>>   > +    } else {
>>>   >          return;
>>>
>>> Why return here? If the clock is optional, a lot of systems will not
>>> have it - that shouldn't prevent the driver from probing. And you are
>>> still not handling the -EPROBE_DEFER case which was mentioned on your
>>> previous submission.
>>
>> Right. The else statement above could/should be:
>>
>> } else if (clk && PTR_ERR(clk) == -EPROBE_DEFER) {
>>           return PTR_ERR(clk);
>> }
> 
> ... plus change the function prototype to return int and propagate
> that error code through brcmf_get_module_param to brcmf_pcie_probe's
> return value. I guess checking clk for NULL is also redundant in this
> case?

Only wanted to give the suggestion to get started. Propagating the 
return value seemed obvious to me, but you are absolutely right. 
PTR_ERR(NULL) will probably be something else than -EPROBE_DEFER but it 
seems odd to me. Maybe PTR_ERR_OR_ZERO(clk) is a better option here.

Regards,
Arend
Alexey Charkov July 31, 2024, 12:56 p.m. UTC | #5
On Wed, Jul 31, 2024 at 3:32 PM Arend van Spriel
<arend.vanspriel@broadcom.com> wrote:
>
> On 7/31/2024 2:01 PM, Alexey Charkov wrote:
> > On Wed, Jul 31, 2024 at 2:15 PM Arend van Spriel
> > <arend.vanspriel@broadcom.com> wrote:
> >>
> >> On 7/31/2024 12:16 PM, Alexey Charkov wrote:
> >>> Hi Jacobe,
> >>>
> >>>
> >>> On 31/07/2024 9:11 am, Jacobe Zang wrote:
> >>>   > WiFi modules often require 32kHz clock to function. Add support to
> >>>   > enable the clock to PCIe driver and move "brcm,bcm4329-fmac" check
> >>>   > to the top of brcmf_of_probe
> >>>   >
> >>>   > Co-developed-by: Ondrej Jirman <megi@xff.cz>
> >>>   > Signed-off-by: Ondrej Jirman <megi@xff.cz>
> >>>   > Signed-off-by: Jacobe Zang <jacobe.zang@wesion.com>
> >>>   > ---
> >>>   >  .../net/wireless/broadcom/brcm80211/brcmfmac/of.c    | 12 +++++++++++-
> >>>   >  1 file changed, 11 insertions(+), 1 deletion(-)
> >>>   >
> >>>   > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> >>> b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> >>>   > index e406e11481a62..7e0a2ad5c7c8a 100644
> >>>   > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> >>>   > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> >>>   > @@ -6,6 +6,7 @@
> >>>   >  #include <linux/of.h>
> >>>   >  #include <linux/of_irq.h>
> >>>   >  #include <linux/of_net.h>
> >>>   > +#include <linux/clk.h>
> >>>   >
> >>>   >  #include <defs.h>
> >>>   >  #include "debug.h"
> >>>   > @@ -70,12 +71,16 @@ void brcmf_of_probe(struct device *dev, enum
> >>> brcmf_bus_type bus_type,
> >>>   >  {
> >>>   >      struct brcmfmac_sdio_pd *sdio = &settings->bus.sdio;
> >>>   >      struct device_node *root, *np = dev->of_node;
> >>>   > +    struct clk *clk;
> >>>   >      const char *prop;
> >>>   >      int irq;
> >>>   >      int err;
> >>>   >      u32 irqf;
> >>>   >      u32 val;
> >>>   >
> >>>   > +    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
> >>>   > +        return;
> >>>
> >>> Did you test this? The DTS patch you sent as part of this series doesn't
> >>> list "brcm,bcm4329-fmac" in the compatible, so this will probably return
> >>> right here, skipping over the rest of your patch.
> >>>
> >>> Please test before resending, both with and without the driver for the
> >>> Bluetooth part of the chip (since it also touches clocks).
> >>>
> >>> You are also changing the behavior for other systems by putting this
> >>> check further up the probe path, which might break things for no reason.
> >>> Better put your clk-related addition below where this check was
> >>> originally, rather than reorder stuff you don't have to reorder.
> >>
> >> That was upon my suggestion. That check was originally at the top of the
> >> function, but people added stuff before that. I agree that makes the
> >> compatible "brcm,brcm4329-fmac" required which is what the textual
> >> binding stated before the switch to YAML was made:
> >>
> >> """
> >> Broadcom BCM43xx Fullmac wireless SDIO devices
> >>
> >> This node provides properties for controlling the Broadcom wireless
> >> device. The
> >> node is expected to be specified as a child node to the SDIO controller that
> >> connects the device to the system.
> >>
> >> Required properties:
> >>
> >>    - compatible : Should be "brcm,bcm4329-fmac".
> >> """
> >>
> >> Not sure whether this is still true for YAML version (poor YAML reading
> >> skills ;-) ), but it should as the switch from textual to YAML should
> >> not have changed the bindings specification.
> >>
> >>>   > +
> >>>   >      /* Apple ARM64 platforms have their own idea of board type,
> >>> passed in
> >>>   >       * via the device tree. They also have an antenna SKU parameter
> >>>   >       */
> >>>   > @@ -113,8 +118,13 @@ void brcmf_of_probe(struct device *dev, enum
> >>> brcmf_bus_type bus_type,
> >>>   >          of_node_put(root);
> >>>   >      }
> >>>   >
> >>>   > -    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
> >>>   > +    clk = devm_clk_get_optional_enabled(dev, "lpo");
> >>>   > +    if (!IS_ERR_OR_NULL(clk)) {
> >>>   > +        brcmf_dbg(INFO, "enabling 32kHz clock\n");
> >>>   > +        clk_set_rate(clk, 32768);
> >>>   > +    } else {
> >>>   >          return;
> >>>
> >>> Why return here? If the clock is optional, a lot of systems will not
> >>> have it - that shouldn't prevent the driver from probing. And you are
> >>> still not handling the -EPROBE_DEFER case which was mentioned on your
> >>> previous submission.
> >>
> >> Right. The else statement above could/should be:
> >>
> >> } else if (clk && PTR_ERR(clk) == -EPROBE_DEFER) {
> >>           return PTR_ERR(clk);
> >> }
> >
> > ... plus change the function prototype to return int and propagate
> > that error code through brcmf_get_module_param to brcmf_pcie_probe's
> > return value. I guess checking clk for NULL is also redundant in this
> > case?
>
> Only wanted to give the suggestion to get started. Propagating the
> return value seemed obvious to me, but you are absolutely right.
> PTR_ERR(NULL) will probably be something else than -EPROBE_DEFER but it
> seems odd to me. Maybe PTR_ERR_OR_ZERO(clk) is a better option here.

Indeed. Perhaps something along the lines of:

       clk = devm_clk_get_optional_enabled(dev, "lpo");
       if (!IS_ERR_OR_NULL(clk)) {
               brcmf_dbg(INFO, "enabling 32kHz clock\n");
               return clk_set_rate(clk, 32768);
       } else {
               return PTR_ERR_OR_ZERO(clk);
       }

... which should then go at the very end of brcmf_of_probe. And all of
the existing void returns should get appropriate errno's. And the
functions prototypes should be updated along the call chain. And then
it would still only work after pwrseq is added to ensure that power
and wake signals are applied correctly along with this clock, as
Sebastian pointed out in the other thread :)

Which really prompts a question: should this clock be added to the
PCIe driver and the respective DT binding in the first place, or
should it instead be claimed by pwrseq, leaving brcmfmac alone?

Best regards,
Alexey
Jacobe Zang Aug. 1, 2024, 3:52 a.m. UTC | #6
>>On 7/31/2024 2:01 PM, Alexey Charkov wrote:
>>> On Wed, Jul 31, 2024 at 2:15 PM Arend van Spriel
>>> <arend.vanspriel@broadcom.com> wrote:
>>>>
>>>> On 7/31/2024 12:16 PM, Alexey Charkov wrote:
>>>>> Hi Jacobe,
>>>>>
>>>>>
>>>>> On 31/07/2024 9:11 am, Jacobe Zang wrote:
>>>>>   > WiFi modules often require 32kHz clock to function. Add support to
>>>>>   > enable the clock to PCIe driver and move "brcm,bcm4329-fmac" check
>>>>>   > to the top of brcmf_of_probe
>>>>>   >
>>>>>   > Co-developed-by: Ondrej Jirman <megi@xff.cz>
>>>>>   > Signed-off-by: Ondrej Jirman <megi@xff.cz>
>>>>>   > Signed-off-by: Jacobe Zang <jacobe.zang@wesion.com>
>>>>>   > ---
>>>>>   >  .../net/wireless/broadcom/brcm80211/brcmfmac/of.c    | 12 +++++++++++-
>>>>>   >  1 file changed, 11 insertions(+), 1 deletion(-)
>>>>>   >
>>>>>   > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
>>>>> b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
>>>>>   > index e406e11481a62..7e0a2ad5c7c8a 100644
>>>>>   > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
>>>>>   > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
>>>>>   > @@ -6,6 +6,7 @@
>>>>>   >  #include <linux/of.h>
>>>>>   >  #include <linux/of_irq.h>
>>>>>   >  #include <linux/of_net.h>
>>>>>   > +#include <linux/clk.h>
>>>>>   >
>>>>>   >  #include <defs.h>
>>>>>   >  #include "debug.h"
>>>>>   > @@ -70,12 +71,16 @@ void brcmf_of_probe(struct device *dev, enum
>>>>> brcmf_bus_type bus_type,
>>>>>   >  {
>>>>>   >      struct brcmfmac_sdio_pd *sdio = &settings->bus.sdio;
>>>>>   >      struct device_node *root, *np = dev->of_node;
>>>>>   > +    struct clk *clk;
>>>>>   >      const char *prop;
>>>>>   >      int irq;
>>>>>   >      int err;
>>>>>   >      u32 irqf;
>>>>>   >      u32 val;
>>>>>   >
>>>>>   > +    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
>>>>>   > +        return;
>>>>>
>>>>> Did you test this? The DTS patch you sent as part of this series doesn't
>>>>> list "brcm,bcm4329-fmac" in the compatible, so this will probably return
>>>>> right here, skipping over the rest of your patch.
>>>>>
>>>>> Please test before resending, both with and without the driver for the
>>>>> Bluetooth part of the chip (since it also touches clocks).
>>>>>
>>>>> You are also changing the behavior for other systems by putting this
>>>>> check further up the probe path, which might break things for no reason.
>>>>> Better put your clk-related addition below where this check was
>>>>> originally, rather than reorder stuff you don't have to reorder.
>>>>
>>>> That was upon my suggestion. That check was originally at the top of the
>>>> function, but people added stuff before that. I agree that makes the
>>>> compatible "brcm,brcm4329-fmac" required which is what the textual
>>>> binding stated before the switch to YAML was made:
>>>>
>>>> """
>>>> Broadcom BCM43xx Fullmac wireless SDIO devices
>>>>
>>>> This node provides properties for controlling the Broadcom wireless
>>>> device. The
>>>> node is expected to be specified as a child node to the SDIO controller that
>>>> connects the device to the system.
>>>>
>>>> Required properties:
>>>>
>>>>    - compatible : Should be "brcm,bcm4329-fmac".
>>>> """
>>>>
>>>> Not sure whether this is still true for YAML version (poor YAML reading
>>>> skills ;-) ), but it should as the switch from textual to YAML should
>>>> not have changed the bindings specification.
>>>>
>>>>>   > +
>>>>>   >      /* Apple ARM64 platforms have their own idea of board type,
>>>>> passed in
>>>>>   >       * via the device tree. They also have an antenna SKU parameter
>>>>>   >       */
>>>>>   > @@ -113,8 +118,13 @@ void brcmf_of_probe(struct device *dev, enum
>>>>> brcmf_bus_type bus_type,
>>>>>   >          of_node_put(root);
>>>>>   >      }
>>>>>   >
>>>>>   > -    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
>>>>>   > +    clk = devm_clk_get_optional_enabled(dev, "lpo");
>>>>>   > +    if (!IS_ERR_OR_NULL(clk)) {
>>>>>   > +        brcmf_dbg(INFO, "enabling 32kHz clock\n");
>>>>>   > +        clk_set_rate(clk, 32768);
>>>>>   > +    } else {
>>>>>   >          return;
>>>>>
>>>>> Why return here? If the clock is optional, a lot of systems will not
>>>>> have it - that shouldn't prevent the driver from probing. And you are
>>>>> still not handling the -EPROBE_DEFER case which was mentioned on your
>>>>> previous submission.
>>>>
>>>> Right. The else statement above could/should be:
>>>>
>>>> } else if (clk && PTR_ERR(clk) == -EPROBE_DEFER) {
>>>>           return PTR_ERR(clk);
>>>> }
>>>
>>> ... plus change the function prototype to return int and propagate
>>> that error code through brcmf_get_module_param to brcmf_pcie_probe's
>>> return value. I guess checking clk for NULL is also redundant in this
>>> case?
>>
>>Only wanted to give the suggestion to get started. Propagating the
>>return value seemed obvious to me, but you are absolutely right.
>>PTR_ERR(NULL) will probably be something else than -EPROBE_DEFER but it
>>seems odd to me. Maybe PTR_ERR_OR_ZERO(clk) is a better option here.
> 
> Indeed. Perhaps something along the lines of:
> 
>        clk = devm_clk_get_optional_enabled(dev, "lpo");
>        if (!IS_ERR_OR_NULL(clk)) {
>                brcmf_dbg(INFO, "enabling 32kHz clock\n");
>                return clk_set_rate(clk, 32768);
>        } else {
>                return PTR_ERR_OR_ZERO(clk);
>        }
> 
> ... which should then go at the very end of brcmf_of_probe. And all of

But before end of brcmf_of_probe is to set interrupt configuration which
wifi chip connect via sdio. Like this:
```
	if (bus_type != BRCMF_BUSTYPE_SDIO)
		return;

	if (of_property_read_u32(np, "brcm,drive-strength", &val) == 0)
		sdio->drive_strength = val;

	/* make sure there are interrupts defined in the node */
	if (!of_property_present(np, "interrupts"))
		return;

	irq = irq_of_parse_and_map(np, 0);
	if (!irq) {
		brcmf_err("interrupt could not be mapped\n");
		return;
	}
	irqf = irqd_get_trigger_type(irq_get_irq_data(irq));

	sdio->oob_irq_supported = true;
	sdio->oob_irq_nr = irq;
	sdio->oob_irq_flags = irqf;
```
So I think the interrupt should be set in the if statement while
bus_type==BRCMF_BUSTYPE_SDIO, and add else statement
to enable clock(or simply put it at the end as Alexey said). And
can also use else-if statement to deal with
bus_type == BRCMF_BUSTYPE_USB or PCIE in the future.

> the existing void returns should get appropriate errno's. And the
> functions prototypes should be updated along the call chain. And then
> it would still only work after pwrseq is added to ensure that power
> and wake signals are applied correctly along with this clock, as
> Sebastian pointed out in the other thread :)
> 
> Which really prompts a question: should this clock be added to the
> PCIe driver and the respective DT binding in the first place, or
> should it instead be claimed by pwrseq, leaving brcmfmac alone?

---
Best Regards
Jacobe
Alexey Charkov Aug. 1, 2024, 7:57 a.m. UTC | #7
On Thu, Aug 1, 2024 at 6:53 AM Jacobe Zang <jacobe.zang@wesion.com> wrote:
>
> >>On 7/31/2024 2:01 PM, Alexey Charkov wrote:
> >>> On Wed, Jul 31, 2024 at 2:15 PM Arend van Spriel
> >>> <arend.vanspriel@broadcom.com> wrote:
> >>>>
> >>>> On 7/31/2024 12:16 PM, Alexey Charkov wrote:
> >>>>> Hi Jacobe,
> >>>>>
> >>>>>
> >>>>> On 31/07/2024 9:11 am, Jacobe Zang wrote:
> >>>>>   > WiFi modules often require 32kHz clock to function. Add support to
> >>>>>   > enable the clock to PCIe driver and move "brcm,bcm4329-fmac" check
> >>>>>   > to the top of brcmf_of_probe
> >>>>>   >
> >>>>>   > Co-developed-by: Ondrej Jirman <megi@xff.cz>
> >>>>>   > Signed-off-by: Ondrej Jirman <megi@xff.cz>
> >>>>>   > Signed-off-by: Jacobe Zang <jacobe.zang@wesion.com>
> >>>>>   > ---
> >>>>>   >  .../net/wireless/broadcom/brcm80211/brcmfmac/of.c    | 12 +++++++++++-
> >>>>>   >  1 file changed, 11 insertions(+), 1 deletion(-)
> >>>>>   >
> >>>>>   > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> >>>>> b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> >>>>>   > index e406e11481a62..7e0a2ad5c7c8a 100644
> >>>>>   > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> >>>>>   > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
> >>>>>   > @@ -6,6 +6,7 @@
> >>>>>   >  #include <linux/of.h>
> >>>>>   >  #include <linux/of_irq.h>
> >>>>>   >  #include <linux/of_net.h>
> >>>>>   > +#include <linux/clk.h>
> >>>>>   >
> >>>>>   >  #include <defs.h>
> >>>>>   >  #include "debug.h"
> >>>>>   > @@ -70,12 +71,16 @@ void brcmf_of_probe(struct device *dev, enum
> >>>>> brcmf_bus_type bus_type,
> >>>>>   >  {
> >>>>>   >      struct brcmfmac_sdio_pd *sdio = &settings->bus.sdio;
> >>>>>   >      struct device_node *root, *np = dev->of_node;
> >>>>>   > +    struct clk *clk;
> >>>>>   >      const char *prop;
> >>>>>   >      int irq;
> >>>>>   >      int err;
> >>>>>   >      u32 irqf;
> >>>>>   >      u32 val;
> >>>>>   >
> >>>>>   > +    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
> >>>>>   > +        return;
> >>>>>
> >>>>> Did you test this? The DTS patch you sent as part of this series doesn't
> >>>>> list "brcm,bcm4329-fmac" in the compatible, so this will probably return
> >>>>> right here, skipping over the rest of your patch.
> >>>>>
> >>>>> Please test before resending, both with and without the driver for the
> >>>>> Bluetooth part of the chip (since it also touches clocks).
> >>>>>
> >>>>> You are also changing the behavior for other systems by putting this
> >>>>> check further up the probe path, which might break things for no reason.
> >>>>> Better put your clk-related addition below where this check was
> >>>>> originally, rather than reorder stuff you don't have to reorder.
> >>>>
> >>>> That was upon my suggestion. That check was originally at the top of the
> >>>> function, but people added stuff before that. I agree that makes the
> >>>> compatible "brcm,brcm4329-fmac" required which is what the textual
> >>>> binding stated before the switch to YAML was made:
> >>>>
> >>>> """
> >>>> Broadcom BCM43xx Fullmac wireless SDIO devices
> >>>>
> >>>> This node provides properties for controlling the Broadcom wireless
> >>>> device. The
> >>>> node is expected to be specified as a child node to the SDIO controller that
> >>>> connects the device to the system.
> >>>>
> >>>> Required properties:
> >>>>
> >>>>    - compatible : Should be "brcm,bcm4329-fmac".
> >>>> """
> >>>>
> >>>> Not sure whether this is still true for YAML version (poor YAML reading
> >>>> skills ;-) ), but it should as the switch from textual to YAML should
> >>>> not have changed the bindings specification.
> >>>>
> >>>>>   > +
> >>>>>   >      /* Apple ARM64 platforms have their own idea of board type,
> >>>>> passed in
> >>>>>   >       * via the device tree. They also have an antenna SKU parameter
> >>>>>   >       */
> >>>>>   > @@ -113,8 +118,13 @@ void brcmf_of_probe(struct device *dev, enum
> >>>>> brcmf_bus_type bus_type,
> >>>>>   >          of_node_put(root);
> >>>>>   >      }
> >>>>>   >
> >>>>>   > -    if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
> >>>>>   > +    clk = devm_clk_get_optional_enabled(dev, "lpo");
> >>>>>   > +    if (!IS_ERR_OR_NULL(clk)) {
> >>>>>   > +        brcmf_dbg(INFO, "enabling 32kHz clock\n");
> >>>>>   > +        clk_set_rate(clk, 32768);
> >>>>>   > +    } else {
> >>>>>   >          return;
> >>>>>
> >>>>> Why return here? If the clock is optional, a lot of systems will not
> >>>>> have it - that shouldn't prevent the driver from probing. And you are
> >>>>> still not handling the -EPROBE_DEFER case which was mentioned on your
> >>>>> previous submission.
> >>>>
> >>>> Right. The else statement above could/should be:
> >>>>
> >>>> } else if (clk && PTR_ERR(clk) == -EPROBE_DEFER) {
> >>>>           return PTR_ERR(clk);
> >>>> }
> >>>
> >>> ... plus change the function prototype to return int and propagate
> >>> that error code through brcmf_get_module_param to brcmf_pcie_probe's
> >>> return value. I guess checking clk for NULL is also redundant in this
> >>> case?
> >>
> >>Only wanted to give the suggestion to get started. Propagating the
> >>return value seemed obvious to me, but you are absolutely right.
> >>PTR_ERR(NULL) will probably be something else than -EPROBE_DEFER but it
> >>seems odd to me. Maybe PTR_ERR_OR_ZERO(clk) is a better option here.
> >
> > Indeed. Perhaps something along the lines of:
> >
> >        clk = devm_clk_get_optional_enabled(dev, "lpo");
> >        if (!IS_ERR_OR_NULL(clk)) {
> >                brcmf_dbg(INFO, "enabling 32kHz clock\n");
> >                return clk_set_rate(clk, 32768);
> >        } else {
> >                return PTR_ERR_OR_ZERO(clk);
> >        }
> >
> > ... which should then go at the very end of brcmf_of_probe. And all of
>
> But before end of brcmf_of_probe is to set interrupt configuration which
> wifi chip connect via sdio. Like this:
> ```
>         if (bus_type != BRCMF_BUSTYPE_SDIO)
>                 return;
>
>         if (of_property_read_u32(np, "brcm,drive-strength", &val) == 0)
>                 sdio->drive_strength = val;
>
>         /* make sure there are interrupts defined in the node */
>         if (!of_property_present(np, "interrupts"))
>                 return;
>
>         irq = irq_of_parse_and_map(np, 0);
>         if (!irq) {
>                 brcmf_err("interrupt could not be mapped\n");
>                 return;
>         }
>         irqf = irqd_get_trigger_type(irq_get_irq_data(irq));
>
>         sdio->oob_irq_supported = true;
>         sdio->oob_irq_nr = irq;
>         sdio->oob_irq_flags = irqf;
> ```
> So I think the interrupt should be set in the if statement while
> bus_type==BRCMF_BUSTYPE_SDIO, and add else statement
> to enable clock(or simply put it at the end as Alexey said). And
> can also use else-if statement to deal with
> bus_type == BRCMF_BUSTYPE_USB or PCIE in the future.

SDIO devices might also want to enable a clock, so I think wrapping
the drive strength and interrupts handling into an if statement and
putting the clock-related stuff right after it (but not in the else
block) is better.

Best regards,
Alexey
diff mbox series

Patch

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
index e406e11481a62..7e0a2ad5c7c8a 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/of.c
@@ -6,6 +6,7 @@ 
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/of_net.h>
+#include <linux/clk.h>
 
 #include <defs.h>
 #include "debug.h"
@@ -70,12 +71,16 @@  void brcmf_of_probe(struct device *dev, enum brcmf_bus_type bus_type,
 {
 	struct brcmfmac_sdio_pd *sdio = &settings->bus.sdio;
 	struct device_node *root, *np = dev->of_node;
+	struct clk *clk;
 	const char *prop;
 	int irq;
 	int err;
 	u32 irqf;
 	u32 val;
 
+	if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
+		return;
+
 	/* Apple ARM64 platforms have their own idea of board type, passed in
 	 * via the device tree. They also have an antenna SKU parameter
 	 */
@@ -113,8 +118,13 @@  void brcmf_of_probe(struct device *dev, enum brcmf_bus_type bus_type,
 		of_node_put(root);
 	}
 
-	if (!np || !of_device_is_compatible(np, "brcm,bcm4329-fmac"))
+	clk = devm_clk_get_optional_enabled(dev, "lpo");
+	if (!IS_ERR_OR_NULL(clk)) {
+		brcmf_dbg(INFO, "enabling 32kHz clock\n");
+		clk_set_rate(clk, 32768);
+	} else {
 		return;
+	}
 
 	err = brcmf_of_get_country_codes(dev, settings);
 	if (err)