[PATCH] pinctrl: armada-37xx: Correct PWM pins definitions

The PWM pins on North Bridge on Armada 37xx can be configured into PWM
or GPIO functions. When in PWM function, each pin can also be configured
to drive low on 0 and tri-state on 1 (LED mode).

The current definitions handle this by declaring two pin groups for each
pin:
- group "pwmN" with functions "pwm" and "gpio"
- group "ledN_od" ("od" for open drain) with functions "led" and "gpio"

This is semantically incorrect. The correct definition for each pin
should be one group with three functions: "pwm", "led" and "gpio".

Change the "pwmN" groups to support "led" function.

Remove "ledN_od" groups. This cannot break backwards compatibility with
older device trees: no device tree uses it since there is no PWM driver
for this SOC yet. Also "ledN_od" groups are not even documented.

Signed-off-by: Marek Behún <kabel@kernel.org>
---
 .../pinctrl/marvell,armada-37xx-pinctrl.txt      |  8 ++++----
 drivers/pinctrl/mvebu/pinctrl-armada-37xx.c      | 16 ++++++++--------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/Documentation/devicetree/bindings/pinctrl/marvell,armada-37xx-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/marvell,armada-37xx-pinctrl.txt
index 38dc56a57760..ecec514b3155 100644
--- a/Documentation/devicetree/bindings/pinctrl/marvell,armada-37xx-pinctrl.txt
+++ b/Documentation/devicetree/bindings/pinctrl/marvell,armada-37xx-pinctrl.txt

@@ -43,19 +43,19 @@ group emmc_nb
 
 group pwm0
  - pin 11 (GPIO1-11)
- - functions pwm, gpio
+ - functions pwm, led, gpio
 
 group pwm1
  - pin 12
- - functions pwm, gpio
+ - functions pwm, led, gpio
 
 group pwm2
  - pin 13
- - functions pwm, gpio
+ - functions pwm, led, gpio
 
 group pwm3
  - pin 14
- - functions pwm, gpio
+ - functions pwm, led, gpio
 
 group pmic1
  - pin 7

diff --git a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c
index 5a68e242f6b3..5cb018f98800 100644
--- a/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c
+++ b/drivers/pinctrl/mvebu/pinctrl-armada-37xx.c

@@ -167,10 +167,14 @@ static struct armada_37xx_pin_group armada_37xx_nb_groups[] = {
 	PIN_GRP_GPIO("jtag", 20, 5, BIT(0), "jtag"),
 	PIN_GRP_GPIO("sdio0", 8, 3, BIT(1), "sdio"),
 	PIN_GRP_GPIO("emmc_nb", 27, 9, BIT(2), "emmc"),
-	PIN_GRP_GPIO("pwm0", 11, 1, BIT(3), "pwm"),
-	PIN_GRP_GPIO("pwm1", 12, 1, BIT(4), "pwm"),
-	PIN_GRP_GPIO("pwm2", 13, 1, BIT(5), "pwm"),
-	PIN_GRP_GPIO("pwm3", 14, 1, BIT(6), "pwm"),
+	PIN_GRP_GPIO_3("pwm0", 11, 1, BIT(3) | BIT(20), 0, BIT(20), BIT(3),
+		       "pwm", "led"),
+	PIN_GRP_GPIO_3("pwm1", 12, 1, BIT(4) | BIT(21), 0, BIT(21), BIT(4),
+		       "pwm", "led"),
+	PIN_GRP_GPIO_3("pwm2", 13, 1, BIT(5) | BIT(22), 0, BIT(22), BIT(5),
+		       "pwm", "led"),
+	PIN_GRP_GPIO_3("pwm3", 14, 1, BIT(6) | BIT(23), 0, BIT(23), BIT(6),
+		       "pwm", "led"),
 	PIN_GRP_GPIO("pmic1", 7, 1, BIT(7), "pmic"),
 	PIN_GRP_GPIO("pmic0", 6, 1, BIT(8), "pmic"),
 	PIN_GRP_GPIO("i2c2", 2, 2, BIT(9), "i2c"),

@@ -184,10 +188,6 @@ static struct armada_37xx_pin_group armada_37xx_nb_groups[] = {
 	PIN_GRP_EXTRA("uart2", 9, 2, BIT(1) | BIT(13) | BIT(14) | BIT(19),
 		      BIT(1) | BIT(13) | BIT(14), BIT(1) | BIT(19),
 		      18, 2, "gpio", "uart"),
-	PIN_GRP_GPIO_2("led0_od", 11, 1, BIT(20), BIT(20), 0, "led"),
-	PIN_GRP_GPIO_2("led1_od", 12, 1, BIT(21), BIT(21), 0, "led"),
-	PIN_GRP_GPIO_2("led2_od", 13, 1, BIT(22), BIT(22), 0, "led"),
-	PIN_GRP_GPIO_2("led3_od", 14, 1, BIT(23), BIT(23), 0, "led"),
 };
 
 static struct armada_37xx_pin_group armada_37xx_sb_groups[] = {

-- 
2.31.1

On Tue, 15 Jun 2021 00:25:27 +0200
Marek Behún [off-list ref] wrote:

The PWM pins on North Bridge on Armada 37xx can be configured into PWM
or GPIO functions. When in PWM function, each pin can also be
configured to drive low on 0 and tri-state on 1 (LED mode).

The current definitions handle this by declaring two pin groups for
each pin:
- group "pwmN" with functions "pwm" and "gpio"
- group "ledN_od" ("od" for open drain) with functions "led" and
"gpio"

This is semantically incorrect. The correct definition for each pin
should be one group with three functions: "pwm", "led" and "gpio".

Change the "pwmN" groups to support "led" function.

Remove "ledN_od" groups. This cannot break backwards compatibility
with older device trees: no device tree uses it since there is no PWM
driver for this SOC yet. Also "ledN_od" groups are not even
documented.

Signed-off-by: Marek Behún <kabel@kernel.org>

Should this also have a Fixes tag? (If it is accepted...?)

On Tue, 15 Jun 2021 00:25:27 +0200, Marek Behún wrote:

The PWM pins on North Bridge on Armada 37xx can be configured into PWM
or GPIO functions. When in PWM function, each pin can also be configured
to drive low on 0 and tri-state on 1 (LED mode).

The current definitions handle this by declaring two pin groups for each
pin:
- group "pwmN" with functions "pwm" and "gpio"
- group "ledN_od" ("od" for open drain) with functions "led" and "gpio"

This is semantically incorrect. The correct definition for each pin
should be one group with three functions: "pwm", "led" and "gpio".

Change the "pwmN" groups to support "led" function.

Remove "ledN_od" groups. This cannot break backwards compatibility with
older device trees: no device tree uses it since there is no PWM driver
for this SOC yet. Also "ledN_od" groups are not even documented.

Signed-off-by: Marek Behún <kabel@kernel.org>
---
 .../pinctrl/marvell,armada-37xx-pinctrl.txt      |  8 ++++----
 drivers/pinctrl/mvebu/pinctrl-armada-37xx.c      | 16 ++++++++--------
 2 files changed, 12 insertions(+), 12 deletions(-)

Acked-by: Rob Herring <robh@kernel.org>