pwm: kconfig: enable kona pwm to be built for cygnus arch

PATCH Superseded Clément Péron 4 participants 6 messages Nov 21, 2018 – Nov 23, 2018 PWM

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Clément Péron

author

2018-11-21 12:35 UTC #0 lore raw

PATCH v2 1/1 pwm: kconfig: enable kona pwm to be built for cygnus arch

The Cygnus architecture use a Kona PWM. This is already present in the device tree but can't be built actually. Hence, allow the Kona PWM to be built for Cygnus arch.

Signed-off-by Clément Péron <[email protected]>

---
 drivers/pwm/Kconfig | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

drivers/pwm/Kconfig +3 -1

index 27e5dd47a01f..982f4059f4e8 100644
@@ -88,7 +88,9 @@ config PWM_BCM_IPROC
 
 config PWM_BCM_KONA
 	tristate "Kona PWM support"
-	depends on ARCH_BCM_MOBILE
+	depends on ARCH_BCM_MOBILE || ARCH_BCM_CYGNUS || COMPILE_TEST
+	depends on HAVE_CLK && HAS_IOMEM
+	default ARCH_BCM_CYGNUS
 	help
 	  Generic PWM framework driver for Broadcom Kona PWM block.

Signature · 1 line

2.19.1

Florian Fainelli

Reviewed-by on v2 1/1

2018-11-21 19:00 UTC #1 lore raw

Quoted 5 lines · Clément Péron

The Cygnus architecture use a Kona PWM. This is already present in the device tree but can't be built actually. Hence, allow the Kona PWM to be built for Cygnus arch.
Signed-off-by Clément Péron <[email protected]>

Reviewed-by Florian Fainelli <[email protected]>

The "default ARCH_BCM_CYGNUS" could arguably cover ARCH_BCM_MOBILE as well, but this is not probably worth a respin just to address that.

Quoted 20 lines

---
 drivers/pwm/Kconfig | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

drivers/pwm/Kconfig +3 -1

index 27e5dd47a01f..982f4059f4e8 100644
@@ -88,7 +88,9 @@ config PWM_BCM_IPROC
 
 config PWM_BCM_KONA
 	tristate "Kona PWM support"
-	depends on ARCH_BCM_MOBILE
+	depends on ARCH_BCM_MOBILE || ARCH_BCM_CYGNUS || COMPILE_TEST
+	depends on HAVE_CLK && HAS_IOMEM
+	default ARCH_BCM_CYGNUS
 	help
 	  Generic PWM framework driver for Broadcom Kona PWM block.

Signature · 1 line

Florian

Scott Branden

Reviewed-by

2018-11-21 19:07 UTC #2 lore raw

Quoted 8 lines · Florian Fainelli

Quoted 5 lines · Clément Péron
The Cygnus architecture use a Kona PWM. This is already present in the device tree but can't be built actually. Hence, allow the Kona PWM to be built for Cygnus arch.
Signed-off-by Clément Péron <[email protected]>
Reviewed-by Florian Fainelli <[email protected]>

Reviewed-by Scott Branden <[email protected]>

Quoted 3 lines

The "default ARCH_BCM_CYGNUS" could arguably cover ARCH_BCM_MOBILE as well, but this is not probably worth a respin just to address that.

Yes, it's fine as is.

Quoted 21 lines

---
  drivers/pwm/Kconfig | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)

drivers/pwm/Kconfig +3 -1

index 27e5dd47a01f..982f4059f4e8 100644
@@ -88,7 +88,9 @@ config PWM_BCM_IPROC
 
  config PWM_BCM_KONA
  	tristate "Kona PWM support"
-	depends on ARCH_BCM_MOBILE
+	depends on ARCH_BCM_MOBILE || ARCH_BCM_CYGNUS || COMPILE_TEST
+	depends on HAVE_CLK && HAS_IOMEM
+	default ARCH_BCM_CYGNUS
  	help
  	  Generic PWM framework driver for Broadcom Kona PWM block.

Uwe Kleine-König

Acked-by on v2 1/1

2018-11-22 20:05 UTC #3 lore raw

In reply to Clément Péron

Hello Clément,

Quoted 14 lines · Clément Péron

The Cygnus architecture use a Kona PWM. This is already present in the device tree but can't be built actually. Hence, allow the Kona PWM to be built for Cygnus arch.
Signed-off-by Clément Péron <[email protected]>
---
 drivers/pwm/Kconfig | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
drivers/pwm/Kconfig +0 -0
index 27e5dd47a01f..982f4059f4e8 100644

drivers/pwm/Kconfig config PWM_BCM_IPROC · line 93

Quoted 7 lines

drivers/pwm/Kconfig +3 -1

@@ -88,7 +88,9 @@ config PWM_BCM_IPROC
 
 config PWM_BCM_KONA
 	tristate "Kona PWM support"
-	depends on ARCH_BCM_MOBILE
+	depends on ARCH_BCM_MOBILE || ARCH_BCM_CYGNUS || COMPILE_TEST
+	depends on HAVE_CLK && HAS_IOMEM
+	default ARCH_BCM_CYGNUS

This looks good. As pointed out before the default is a bit strange and could include ARCH_BCM_MOBILE for symmetry.

Anyhow:

Acked-by Uwe Kleine-König <[email protected]>

Related to this driver I have a set of questions: If the disable callback completed, does the hardware still drive the pin? If yes, would it be possible to disable the pin driver such that the pin gets high-Z? If yes, how?

Best regards
Uwe

Signature · 2 lines

Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

Clément Péron

author

2018-11-23 09:31 UTC #4 lore raw

Hi,

Quoted 19 lines · Uwe Kleine-König

Hello Clément,
Quoted 15 lines · Clément Péron
The Cygnus architecture use a Kona PWM. This is already present in the device tree but can't be built actually. Hence, allow the Kona PWM to be built for Cygnus arch.
Signed-off-by Clément Péron <[email protected]>
---
 drivers/pwm/Kconfig | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
drivers/pwm/Kconfig +0 -0
index 27e5dd47a01f..982f4059f4e8 100644
@@ -88,7 +88,9 @@ config PWM_BCM_IPROC
 

Quoted 9 lines

drivers/pwm/Kconfig config PWM_BCM_IPROC · line 93
Quoted 6 lines
drivers/pwm/Kconfig +3 -1
 config PWM_BCM_KONA
      tristate "Kona PWM support"
-     depends on ARCH_BCM_MOBILE
+     depends on ARCH_BCM_MOBILE || ARCH_BCM_CYGNUS || COMPILE_TEST
+     depends on HAVE_CLK && HAS_IOMEM
+     default ARCH_BCM_CYGNUS
This looks good. As pointed out before the default is a bit strange and could include ARCH_BCM_MOBILE for symmetry.

Ok, let me resend a v3

Quoted 9 lines

Anyhow:
Acked-by Uwe Kleine-König <[email protected]>
Related to this driver I have a set of questions: If the disable callback completed, does the hardware still drive the pin? If yes, would it be possible to disable the pin driver such that the pin gets high-Z? If yes, how?

The output pin type is configured with the bit "21:16 PWMOUT_TYPE RW default 0x3F" in the Control register PWM_CONTROL_TYPE_SHIFT macro in the driver
Datasheets says : "When set to 1 the PWM Output signal will have a push/pull type.When set to 0 the PWM Output signal will have an open drain output type.Recommend to leave it push/pull type."

In the driver we actually set push/pull mode for all channels :
/* Set push/pull for all channels */
for (chan = 0; chan < kp->chip.npwm; chan++)
value |= (1 << PWM_CONTROL_TYPE_SHIFT(chan));

Regards,
Clement

Quoted 7 lines

Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | http://www.pengutronix.de/ |

Uwe Kleine-König

2018-11-23 10:25 UTC #5 lore raw

Hello Clément,

Quoted 14 lines · Clément Péron

Quoted 4 lines · Uwe Kleine-König
Related to this driver I have a set of questions: If the disable callback completed, does the hardware still drive the pin? If yes, would it be possible to disable the pin driver such that the pin gets high-Z? If yes, how?
The output pin type is configured with the bit "21:16 PWMOUT_TYPE RW default 0x3F" in the Control register PWM_CONTROL_TYPE_SHIFT macro in the driver
Datasheets says : "When set to 1 the PWM Output signal will have a push/pull type.When set to 0 the PWM Output signal will have an open drain output type.Recommend to leave it push/pull type."

Quoted 4 lines

In the driver we actually set push/pull mode for all channels :
/* Set push/pull for all channels */
for (chan = 0; chan < kp->chip.npwm; chan++)
value |= (1 << PWM_CONTROL_TYPE_SHIFT(chan));

So if disabling the output driver was part of the requirements for .disable the bcm-kona driver could not implement this for both inverted and uninverted PWMs. (At least not without resorting to pinmuxing.)

Thanks
Uwe

Signature · 2 lines

Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |