diff mbox series

[1/2] phy: samsung: phy-exynos-pcie: sanitize init/power_on callbacks

Message ID 20220628220409.26545-1-m.szyprowski@samsung.com
State New
Headers show
Series [1/2] phy: samsung: phy-exynos-pcie: sanitize init/power_on callbacks | expand

Commit Message

Marek Szyprowski June 28, 2022, 10:04 p.m. UTC
The exynos-pcie driver called phy_power_on() and then phy_init() for some
historical reasons. However the generic PHY framework assumes that the
proper sequence is to call phy_init() first, then phy_power_on(). The
operations done by both functions should be considered as one action and
as such they are called by the exynos-pcie driver (without doing anything
between them). The initialization is just a sequence of register writes,
which cannot be altered, without breaking the hardware operation.

To match the generic PHY framework requirement, simply move all register
writes to the phy_init()/phy_exit() and drop power_on()/power_off()
callbacks. This way the driver will also work with the old (incorrect)
PHY initialization call sequence.

Reported-by: Bjorn Helgaas <helgaas@kernel.org>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
---
 drivers/phy/samsung/phy-exynos-pcie.c | 25 +++++++++----------------
 1 file changed, 9 insertions(+), 16 deletions(-)

Comments

Vinod Koul July 5, 2022, 6:25 a.m. UTC | #1
On 29-06-22, 00:04, Marek Szyprowski wrote:
> The exynos-pcie driver called phy_power_on() and then phy_init() for some
> historical reasons. However the generic PHY framework assumes that the
> proper sequence is to call phy_init() first, then phy_power_on(). The
> operations done by both functions should be considered as one action and
> as such they are called by the exynos-pcie driver (without doing anything
> between them). The initialization is just a sequence of register writes,
> which cannot be altered, without breaking the hardware operation.
> 
> To match the generic PHY framework requirement, simply move all register
> writes to the phy_init()/phy_exit() and drop power_on()/power_off()
> callbacks. This way the driver will also work with the old (incorrect)
> PHY initialization call sequence.

Is the plan to merge thru pcie tree?

> 
> Reported-by: Bjorn Helgaas <helgaas@kernel.org>
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> ---
>  drivers/phy/samsung/phy-exynos-pcie.c | 25 +++++++++----------------
>  1 file changed, 9 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/phy/samsung/phy-exynos-pcie.c b/drivers/phy/samsung/phy-exynos-pcie.c
> index 578cfe07d07a..53c9230c2907 100644
> --- a/drivers/phy/samsung/phy-exynos-pcie.c
> +++ b/drivers/phy/samsung/phy-exynos-pcie.c
> @@ -51,6 +51,13 @@ static int exynos5433_pcie_phy_init(struct phy *phy)
>  {
>  	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
>  
> +	regmap_update_bits(ep->pmureg, EXYNOS5433_PMU_PCIE_PHY_OFFSET,
> +			   BIT(0), 1);
> +	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_GLOBAL_RESET,
> +			   PCIE_APP_REQ_EXIT_L1_MODE, 0);
> +	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_L1SUB_CM_CON,
> +			   PCIE_REFCLK_GATING_EN, 0);
> +

why not retain exynos5433_pcie_phy_power_on() and call it from here and
drop in ops. It would be clear to reader that these are for turning on
the phy...

>  	regmap_update_bits(ep->fsysreg,	PCIE_EXYNOS5433_PHY_COMMON_RESET,
>  			   PCIE_PHY_RESET, 1);
>  	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_MAC_RESET,
> @@ -109,20 +116,7 @@ static int exynos5433_pcie_phy_init(struct phy *phy)
>  	return 0;
>  }
>  
> -static int exynos5433_pcie_phy_power_on(struct phy *phy)
> -{
> -	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
> -
> -	regmap_update_bits(ep->pmureg, EXYNOS5433_PMU_PCIE_PHY_OFFSET,
> -			   BIT(0), 1);
> -	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_GLOBAL_RESET,
> -			   PCIE_APP_REQ_EXIT_L1_MODE, 0);
> -	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_L1SUB_CM_CON,
> -			   PCIE_REFCLK_GATING_EN, 0);
> -	return 0;
> -}
> -
> -static int exynos5433_pcie_phy_power_off(struct phy *phy)
> +static int exynos5433_pcie_phy_exit(struct phy *phy)
>  {
>  	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
>  
> @@ -135,8 +129,7 @@ static int exynos5433_pcie_phy_power_off(struct phy *phy)
>  
>  static const struct phy_ops exynos5433_phy_ops = {
>  	.init		= exynos5433_pcie_phy_init,
> -	.power_on	= exynos5433_pcie_phy_power_on,
> -	.power_off	= exynos5433_pcie_phy_power_off,
> +	.exit		= exynos5433_pcie_phy_exit,
>  	.owner		= THIS_MODULE,
>  };
>  
> -- 
> 2.17.1
Bjorn Helgaas July 12, 2022, 8:12 p.m. UTC | #2
On Tue, Jul 05, 2022 at 11:55:23AM +0530, Vinod Koul wrote:
> On 29-06-22, 00:04, Marek Szyprowski wrote:
> > The exynos-pcie driver called phy_power_on() and then phy_init() for some
> > historical reasons. However the generic PHY framework assumes that the
> > proper sequence is to call phy_init() first, then phy_power_on(). The
> > operations done by both functions should be considered as one action and
> > as such they are called by the exynos-pcie driver (without doing anything
> > between them). The initialization is just a sequence of register writes,
> > which cannot be altered, without breaking the hardware operation.
> > 
> > To match the generic PHY framework requirement, simply move all register
> > writes to the phy_init()/phy_exit() and drop power_on()/power_off()
> > callbacks. This way the driver will also work with the old (incorrect)
> > PHY initialization call sequence.
> 
> Is the plan to merge thru pcie tree?

I guess these patches should go together.  I don't see any major
exynos series pending, but I do have two minor pci-exynos.c patches in
the queue.

If you ack it (after resolution of your question below) I'd be happy
to take both if it doesn't cause trouble for you.

> > Reported-by: Bjorn Helgaas <helgaas@kernel.org>
> > Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
> > ---
> >  drivers/phy/samsung/phy-exynos-pcie.c | 25 +++++++++----------------
> >  1 file changed, 9 insertions(+), 16 deletions(-)
> > 
> > diff --git a/drivers/phy/samsung/phy-exynos-pcie.c b/drivers/phy/samsung/phy-exynos-pcie.c
> > index 578cfe07d07a..53c9230c2907 100644
> > --- a/drivers/phy/samsung/phy-exynos-pcie.c
> > +++ b/drivers/phy/samsung/phy-exynos-pcie.c
> > @@ -51,6 +51,13 @@ static int exynos5433_pcie_phy_init(struct phy *phy)
> >  {
> >  	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
> >  
> > +	regmap_update_bits(ep->pmureg, EXYNOS5433_PMU_PCIE_PHY_OFFSET,
> > +			   BIT(0), 1);
> > +	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_GLOBAL_RESET,
> > +			   PCIE_APP_REQ_EXIT_L1_MODE, 0);
> > +	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_L1SUB_CM_CON,
> > +			   PCIE_REFCLK_GATING_EN, 0);
> > +
> 
> why not retain exynos5433_pcie_phy_power_on() and call it from here and
> drop in ops. It would be clear to reader that these are for turning on
> the phy...
> 
> >  	regmap_update_bits(ep->fsysreg,	PCIE_EXYNOS5433_PHY_COMMON_RESET,
> >  			   PCIE_PHY_RESET, 1);
> >  	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_MAC_RESET,
> > @@ -109,20 +116,7 @@ static int exynos5433_pcie_phy_init(struct phy *phy)
> >  	return 0;
> >  }
> >  
> > -static int exynos5433_pcie_phy_power_on(struct phy *phy)
> > -{
> > -	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
> > -
> > -	regmap_update_bits(ep->pmureg, EXYNOS5433_PMU_PCIE_PHY_OFFSET,
> > -			   BIT(0), 1);
> > -	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_GLOBAL_RESET,
> > -			   PCIE_APP_REQ_EXIT_L1_MODE, 0);
> > -	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_L1SUB_CM_CON,
> > -			   PCIE_REFCLK_GATING_EN, 0);
> > -	return 0;
> > -}
> > -
> > -static int exynos5433_pcie_phy_power_off(struct phy *phy)
> > +static int exynos5433_pcie_phy_exit(struct phy *phy)
> >  {
> >  	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
> >  
> > @@ -135,8 +129,7 @@ static int exynos5433_pcie_phy_power_off(struct phy *phy)
> >  
> >  static const struct phy_ops exynos5433_phy_ops = {
> >  	.init		= exynos5433_pcie_phy_init,
> > -	.power_on	= exynos5433_pcie_phy_power_on,
> > -	.power_off	= exynos5433_pcie_phy_power_off,
> > +	.exit		= exynos5433_pcie_phy_exit,
> >  	.owner		= THIS_MODULE,
> >  };
> >  
> > -- 
> > 2.17.1
> 
> -- 
> ~Vinod
> 
> -- 
> linux-phy mailing list
> linux-phy@lists.infradead.org
> https://lists.infradead.org/mailman/listinfo/linux-phy
Vinod Koul July 15, 2022, 11:35 a.m. UTC | #3
On 29-06-22, 00:04, Marek Szyprowski wrote:
> The exynos-pcie driver called phy_power_on() and then phy_init() for some
> historical reasons. However the generic PHY framework assumes that the
> proper sequence is to call phy_init() first, then phy_power_on(). The
> operations done by both functions should be considered as one action and
> as such they are called by the exynos-pcie driver (without doing anything
> between them). The initialization is just a sequence of register writes,
> which cannot be altered, without breaking the hardware operation.
> 
> To match the generic PHY framework requirement, simply move all register
> writes to the phy_init()/phy_exit() and drop power_on()/power_off()
> callbacks. This way the driver will also work with the old (incorrect)
> PHY initialization call sequence.

Acked-By: Vinod Koul <vkoul@kernel.org>
Vinod Koul July 15, 2022, 11:35 a.m. UTC | #4
On 12-07-22, 15:12, Bjorn Helgaas wrote:
> On Tue, Jul 05, 2022 at 11:55:23AM +0530, Vinod Koul wrote:
> > On 29-06-22, 00:04, Marek Szyprowski wrote:
> > > The exynos-pcie driver called phy_power_on() and then phy_init() for some
> > > historical reasons. However the generic PHY framework assumes that the
> > > proper sequence is to call phy_init() first, then phy_power_on(). The
> > > operations done by both functions should be considered as one action and
> > > as such they are called by the exynos-pcie driver (without doing anything
> > > between them). The initialization is just a sequence of register writes,
> > > which cannot be altered, without breaking the hardware operation.
> > > 
> > > To match the generic PHY framework requirement, simply move all register
> > > writes to the phy_init()/phy_exit() and drop power_on()/power_off()
> > > callbacks. This way the driver will also work with the old (incorrect)
> > > PHY initialization call sequence.
> > 
> > Is the plan to merge thru pcie tree?
> 
> I guess these patches should go together.  I don't see any major
> exynos series pending, but I do have two minor pci-exynos.c patches in
> the queue.
> 
> If you ack it (after resolution of your question below) I'd be happy
> to take both if it doesn't cause trouble for you.

Done now.
Bjorn Helgaas July 15, 2022, 11:21 p.m. UTC | #5
On Wed, Jun 29, 2022 at 12:04:08AM +0200, Marek Szyprowski wrote:
> The exynos-pcie driver called phy_power_on() and then phy_init() for some
> historical reasons. However the generic PHY framework assumes that the
> proper sequence is to call phy_init() first, then phy_power_on(). The
> operations done by both functions should be considered as one action and
> as such they are called by the exynos-pcie driver (without doing anything
> between them). The initialization is just a sequence of register writes,
> which cannot be altered, without breaking the hardware operation.
> 
> To match the generic PHY framework requirement, simply move all register
> writes to the phy_init()/phy_exit() and drop power_on()/power_off()
> callbacks. This way the driver will also work with the old (incorrect)
> PHY initialization call sequence.
> 
> Reported-by: Bjorn Helgaas <helgaas@kernel.org>
> Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>

Both applied to pci/ctrl/exynos for v5.20, thanks!

> ---
>  drivers/phy/samsung/phy-exynos-pcie.c | 25 +++++++++----------------
>  1 file changed, 9 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/phy/samsung/phy-exynos-pcie.c b/drivers/phy/samsung/phy-exynos-pcie.c
> index 578cfe07d07a..53c9230c2907 100644
> --- a/drivers/phy/samsung/phy-exynos-pcie.c
> +++ b/drivers/phy/samsung/phy-exynos-pcie.c
> @@ -51,6 +51,13 @@ static int exynos5433_pcie_phy_init(struct phy *phy)
>  {
>  	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
>  
> +	regmap_update_bits(ep->pmureg, EXYNOS5433_PMU_PCIE_PHY_OFFSET,
> +			   BIT(0), 1);
> +	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_GLOBAL_RESET,
> +			   PCIE_APP_REQ_EXIT_L1_MODE, 0);
> +	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_L1SUB_CM_CON,
> +			   PCIE_REFCLK_GATING_EN, 0);
> +
>  	regmap_update_bits(ep->fsysreg,	PCIE_EXYNOS5433_PHY_COMMON_RESET,
>  			   PCIE_PHY_RESET, 1);
>  	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_MAC_RESET,
> @@ -109,20 +116,7 @@ static int exynos5433_pcie_phy_init(struct phy *phy)
>  	return 0;
>  }
>  
> -static int exynos5433_pcie_phy_power_on(struct phy *phy)
> -{
> -	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
> -
> -	regmap_update_bits(ep->pmureg, EXYNOS5433_PMU_PCIE_PHY_OFFSET,
> -			   BIT(0), 1);
> -	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_GLOBAL_RESET,
> -			   PCIE_APP_REQ_EXIT_L1_MODE, 0);
> -	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_L1SUB_CM_CON,
> -			   PCIE_REFCLK_GATING_EN, 0);
> -	return 0;
> -}
> -
> -static int exynos5433_pcie_phy_power_off(struct phy *phy)
> +static int exynos5433_pcie_phy_exit(struct phy *phy)
>  {
>  	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
>  
> @@ -135,8 +129,7 @@ static int exynos5433_pcie_phy_power_off(struct phy *phy)
>  
>  static const struct phy_ops exynos5433_phy_ops = {
>  	.init		= exynos5433_pcie_phy_init,
> -	.power_on	= exynos5433_pcie_phy_power_on,
> -	.power_off	= exynos5433_pcie_phy_power_off,
> +	.exit		= exynos5433_pcie_phy_exit,
>  	.owner		= THIS_MODULE,
>  };
>  
> -- 
> 2.17.1
> 
> 
> -- 
> linux-phy mailing list
> linux-phy@lists.infradead.org
> https://lists.infradead.org/mailman/listinfo/linux-phy
diff mbox series

Patch

diff --git a/drivers/phy/samsung/phy-exynos-pcie.c b/drivers/phy/samsung/phy-exynos-pcie.c
index 578cfe07d07a..53c9230c2907 100644
--- a/drivers/phy/samsung/phy-exynos-pcie.c
+++ b/drivers/phy/samsung/phy-exynos-pcie.c
@@ -51,6 +51,13 @@  static int exynos5433_pcie_phy_init(struct phy *phy)
 {
 	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
 
+	regmap_update_bits(ep->pmureg, EXYNOS5433_PMU_PCIE_PHY_OFFSET,
+			   BIT(0), 1);
+	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_GLOBAL_RESET,
+			   PCIE_APP_REQ_EXIT_L1_MODE, 0);
+	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_L1SUB_CM_CON,
+			   PCIE_REFCLK_GATING_EN, 0);
+
 	regmap_update_bits(ep->fsysreg,	PCIE_EXYNOS5433_PHY_COMMON_RESET,
 			   PCIE_PHY_RESET, 1);
 	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_MAC_RESET,
@@ -109,20 +116,7 @@  static int exynos5433_pcie_phy_init(struct phy *phy)
 	return 0;
 }
 
-static int exynos5433_pcie_phy_power_on(struct phy *phy)
-{
-	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
-
-	regmap_update_bits(ep->pmureg, EXYNOS5433_PMU_PCIE_PHY_OFFSET,
-			   BIT(0), 1);
-	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_GLOBAL_RESET,
-			   PCIE_APP_REQ_EXIT_L1_MODE, 0);
-	regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_L1SUB_CM_CON,
-			   PCIE_REFCLK_GATING_EN, 0);
-	return 0;
-}
-
-static int exynos5433_pcie_phy_power_off(struct phy *phy)
+static int exynos5433_pcie_phy_exit(struct phy *phy)
 {
 	struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
 
@@ -135,8 +129,7 @@  static int exynos5433_pcie_phy_power_off(struct phy *phy)
 
 static const struct phy_ops exynos5433_phy_ops = {
 	.init		= exynos5433_pcie_phy_init,
-	.power_on	= exynos5433_pcie_phy_power_on,
-	.power_off	= exynos5433_pcie_phy_power_off,
+	.exit		= exynos5433_pcie_phy_exit,
 	.owner		= THIS_MODULE,
 };