[PATCH 1/1] i3c: master: svc: Modify enabled_events bit 7:0 to act as IBI enable counter

[PATCH 1/1] i3c: master: svc: Modify enabled_events bit 7:0 to act as IBI enable counter

[Frank Li]

Fix issue where disabling IBI on one device disables the entire IBI
interrupt. Modify bit 7:0 of enabled_events to serve as an IBI enable
counter, ensuring that the system IBI interrupt is disabled only when all
I3C devices have IBI disabled.

Cc: stable@kernel.org
Fixes: 7ff730ca458e ("i3c: master: svc: enable the interrupt in the enable ibi function")
Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/i3c/master/svc-i3c-master.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index d1ebfba3739c1..66fe0fc12c897 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -130,8 +130,8 @@
 /* This parameter depends on the implementation and may be tuned */
 #define SVC_I3C_FIFO_SIZE 16
 
-#define SVC_I3C_EVENT_IBI	BIT(0)
-#define SVC_I3C_EVENT_HOTJOIN	BIT(1)
+#define SVC_I3C_EVENT_IBI	GENMASK(7, 0)
+#define SVC_I3C_EVENT_HOTJOIN	BIT(31)
 
 struct svc_i3c_cmd {
 	u8 addr;
@@ -214,7 +214,7 @@ struct svc_i3c_master {
 		spinlock_t lock;
 	} ibi;
 	struct mutex lock;
-	int enabled_events;
+	u32 enabled_events;
 };
 
 /**
@@ -1532,7 +1532,7 @@ static int svc_i3c_master_enable_ibi(struct i3c_dev_desc *dev)
 		return ret;
 	}
 
-	master->enabled_events |= SVC_I3C_EVENT_IBI;
+	master->enabled_events++;
 	svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);
 
 	return i3c_master_enec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
@@ -1544,7 +1544,7 @@ static int svc_i3c_master_disable_ibi(struct i3c_dev_desc *dev)
 	struct svc_i3c_master *master = to_svc_i3c_master(m);
 	int ret;
 
-	master->enabled_events &= ~SVC_I3C_EVENT_IBI;
+	master->enabled_events--;
 	if (!master->enabled_events)
 		svc_i3c_master_disable_interrupts(master);
 
-- 
2.34.1

Re: [PATCH 1/1] i3c: master: svc: Modify enabled_events bit 7:0 to act as IBI enable counter

[Miquel Raynal]

Hi Frank,

Frank.Li@nxp.com wrote on Thu, 24 Oct 2024 16:38:55 -0400:

> Fix issue where disabling IBI on one device disables the entire IBI
> interrupt. Modify bit 7:0 of enabled_events to serve as an IBI enable

Is this bitfield arbitrary?

Is there a rationale behind it?

> counter, ensuring that the system IBI interrupt is disabled only when all
> I3C devices have IBI disabled.
> 
> Cc: stable@kernel.org
> Fixes: 7ff730ca458e ("i3c: master: svc: enable the interrupt in the enable ibi function")
> Signed-off-by: Frank Li <Frank.Li@nxp.com>

Anyway,

Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>

Thanks,
Miquèl

Re: [PATCH 1/1] i3c: master: svc: Modify enabled_events bit 7:0 to act as IBI enable counter

[Frank Li]

On Fri, Oct 25, 2024 at 09:53:18AM +0200, Miquel Raynal wrote:
> Hi Frank,
>
> Frank.Li@nxp.com wrote on Thu, 24 Oct 2024 16:38:55 -0400:
>
> > Fix issue where disabling IBI on one device disables the entire IBI
> > interrupt. Modify bit 7:0 of enabled_events to serve as an IBI enable
>
> Is this bitfield arbitrary?
>
> Is there a rationale behind it?

Max devices number under a I3C bus is 128 because dynamic address is 7 bit.
So 8 bits for it should be enough.

Bit31 as hotjoin, Bit30 reserved as control switch request.

Frank

>
> > counter, ensuring that the system IBI interrupt is disabled only when all
> > I3C devices have IBI disabled.
> >
> > Cc: stable@kernel.org
> > Fixes: 7ff730ca458e ("i3c: master: svc: enable the interrupt in the enable ibi function")
> > Signed-off-by: Frank Li <Frank.Li@nxp.com>
>
> Anyway,
>
> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
>
> Thanks,
> Miquèl

Re: [PATCH 1/1] i3c: master: svc: Modify enabled_events bit 7:0 to act as IBI enable counter

[Miquel Raynal]

Hi Frank,

Frank.li@nxp.com wrote on Fri, 25 Oct 2024 10:00:50 -0400:

> On Fri, Oct 25, 2024 at 09:53:18AM +0200, Miquel Raynal wrote:
> > Hi Frank,
> >
> > Frank.Li@nxp.com wrote on Thu, 24 Oct 2024 16:38:55 -0400:
> >  
> > > Fix issue where disabling IBI on one device disables the entire IBI
> > > interrupt. Modify bit 7:0 of enabled_events to serve as an IBI enable  
> >
> > Is this bitfield arbitrary?
> >
> > Is there a rationale behind it?  
> 
> Max devices number under a I3C bus is 128 because dynamic address is 7 bit.
> So 8 bits for it should be enough.
> 
> Bit31 as hotjoin, Bit30 reserved as control switch request.

Makes sense.

Thanks,
Miquèl

Re: [PATCH 1/1] i3c: master: svc: Modify enabled_events bit 7:0 to act as IBI enable counter

[Alexandre Belloni]

Hello,

On 24/10/2024 16:38:55-0400, Frank Li wrote:
> Fix issue where disabling IBI on one device disables the entire IBI
> interrupt. Modify bit 7:0 of enabled_events to serve as an IBI enable
> counter, ensuring that the system IBI interrupt is disabled only when all
> I3C devices have IBI disabled.
> 
> Cc: stable@kernel.org
> Fixes: 7ff730ca458e ("i3c: master: svc: enable the interrupt in the enable ibi function")
> Signed-off-by: Frank Li <Frank.Li@nxp.com>

This doesn't apply on i3c/next after applying your patches, can you
rebase?

> ---
>  drivers/i3c/master/svc-i3c-master.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
> index d1ebfba3739c1..66fe0fc12c897 100644
> --- a/drivers/i3c/master/svc-i3c-master.c
> +++ b/drivers/i3c/master/svc-i3c-master.c
> @@ -130,8 +130,8 @@
>  /* This parameter depends on the implementation and may be tuned */
>  #define SVC_I3C_FIFO_SIZE 16
>  
> -#define SVC_I3C_EVENT_IBI	BIT(0)
> -#define SVC_I3C_EVENT_HOTJOIN	BIT(1)
> +#define SVC_I3C_EVENT_IBI	GENMASK(7, 0)
> +#define SVC_I3C_EVENT_HOTJOIN	BIT(31)
>  
>  struct svc_i3c_cmd {
>  	u8 addr;
> @@ -214,7 +214,7 @@ struct svc_i3c_master {
>  		spinlock_t lock;
>  	} ibi;
>  	struct mutex lock;
> -	int enabled_events;
> +	u32 enabled_events;
>  };
>  
>  /**
> @@ -1532,7 +1532,7 @@ static int svc_i3c_master_enable_ibi(struct i3c_dev_desc *dev)
>  		return ret;
>  	}
>  
> -	master->enabled_events |= SVC_I3C_EVENT_IBI;
> +	master->enabled_events++;
>  	svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);
>  
>  	return i3c_master_enec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
> @@ -1544,7 +1544,7 @@ static int svc_i3c_master_disable_ibi(struct i3c_dev_desc *dev)
>  	struct svc_i3c_master *master = to_svc_i3c_master(m);
>  	int ret;
>  
> -	master->enabled_events &= ~SVC_I3C_EVENT_IBI;
> +	master->enabled_events--;
>  	if (!master->enabled_events)
>  		svc_i3c_master_disable_interrupts(master);
>  
> -- 
> 2.34.1
> 

-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com