[PATCH v2 0/3] pinctrl: at91: allow disabled gpio controllers

[PATCH v2 0/3] pinctrl: at91: allow disabled gpio controllers

[Ludovic Desroches]

Hi Linus,

I have updated the previous version. I have tried to follow your advice but it
doesn't seem to be the best solution in my case.

You told me to use gpiochip_add_pingroup_range() instead of
pinctrl_add_gpio_range(). I agree that is the proper way to manage a gap but it
only solves my issue on gpio side but not on muxing side. I still need some
fixes. Moreover it involves to add the gpio-ranges property so to update our
dtsi files so it will break backward compatibility.

By the way, I would like to be co-maintainer on this driver as it seems the
maintainer is not very active at the moment.

Regards

Ludovic

Ludovic Desroches (3):
  pinctrl: at91: allow disabled pio controllers
  ARM: at91/dt: sama5d4: add pioD controller
  MAINTAINERS: add maintainer for pinctrl-at91

 MAINTAINERS                    |  1 +
 arch/arm/boot/dts/sama5d4.dtsi | 13 +++++++++++++
 drivers/pinctrl/pinctrl-at91.c | 30 ++++++++++++++++++++++--------
 3 files changed, 36 insertions(+), 8 deletions(-)

-- 
2.2.0

[PATCH 1/3] pinctrl: at91: allow disabled pio controllers

[Ludovic Desroches]

at91 pinctrl was not designed to support disabled or unused pio controllers.
All the pio controllers have to be declared, then set status to
disabled if you don't want to use it.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
---
 drivers/pinctrl/pinctrl-at91.c | 30 ++++++++++++++++++++++--------
 1 file changed, 22 insertions(+), 8 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-at91.c b/drivers/pinctrl/pinctrl-at91.c
index dfd021e..fc9afb4 100644
--- a/drivers/pinctrl/pinctrl-at91.c
+++ b/drivers/pinctrl/pinctrl-at91.c
@@ -178,6 +178,7 @@ struct at91_pinctrl {
 	struct pinctrl_dev	*pctl;
 
 	int			nbanks;
+	int			nactive_banks;
 
 	uint32_t		*mux_mask;
 	int			nmux;
@@ -982,6 +983,8 @@ static void at91_pinctrl_child_count(struct at91_pinctrl *info,
 	for_each_child_of_node(np, child) {
 		if (of_device_is_compatible(child, gpio_compat)) {
 			info->nbanks++;
+			if (of_device_is_available(child))
+				info->nactive_banks;
 		} else {
 			info->nfunctions++;
 			info->ngroups += of_get_child_count(child);
@@ -1145,8 +1148,12 @@ static int at91_pinctrl_probe_dt(struct platform_device *pdev,
 	dev_dbg(&pdev->dev, "mux-mask\n");
 	tmp = info->mux_mask;
 	for (i = 0; i < info->nbanks; i++) {
+		if (!gpio_chips[i]) {
+			tmp += info->nmux;
+			continue;
+		}
 		for (j = 0; j < info->nmux; j++, tmp++) {
-			dev_dbg(&pdev->dev, "%d:%d\t0x%x\n", i, j, tmp[0]);
+			dev_dbg(&pdev->dev, "pio%c:periphal %c\t0x%x\n", 'A' + i, 'A' + j, tmp[0]);
 		}
 	}
 
@@ -1185,7 +1192,7 @@ static int at91_pinctrl_probe(struct platform_device *pdev)
 {
 	struct at91_pinctrl *info;
 	struct pinctrl_pin_desc *pdesc;
-	int ret, i, j, k;
+	int ret, i, j, k, ngpio_chips_enabled = 0;
 
 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
 	if (!info)
@@ -1201,11 +1208,15 @@ static int at91_pinctrl_probe(struct platform_device *pdev)
 	 * need this to proceed.
 	 */
 	for (i = 0; i < info->nbanks; i++) {
-		if (!gpio_chips[i]) {
-			dev_warn(&pdev->dev, "GPIO chip %d not registered yet\n", i);
-			devm_kfree(&pdev->dev, info);
-			return -EPROBE_DEFER;
-		}
+		if (gpio_chips[i])
+			ngpio_chips_enabled++;
+	}
+	if (ngpio_chips_enabled < info->nactive_banks) {
+		dev_warn(&pdev->dev,
+			 "All GPIO chips are not registered yet (%d/%d)\n",
+			 ngpio_chips_enabled, info->nactive_banks);
+		devm_kfree(&pdev->dev, info);
+		return -EPROBE_DEFER;
 	}
 
 	at91_pinctrl_desc.name = dev_name(&pdev->dev);
@@ -1235,7 +1246,8 @@ static int at91_pinctrl_probe(struct platform_device *pdev)
 
 	/* We will handle a range of GPIO pins */
 	for (i = 0; i < info->nbanks; i++)
-		pinctrl_add_gpio_range(info->pctl, &gpio_chips[i]->range);
+		if (gpio_chips[i])
+			pinctrl_add_gpio_range(info->pctl, &gpio_chips[i]->range);
 
 	dev_info(&pdev->dev, "initialized AT91 pinctrl driver\n");
 
@@ -1682,6 +1694,8 @@ static void at91_gpio_probe_fixup(void)
 
 	for (i = 0; i < gpio_banks; i++) {
 		at91_gpio = gpio_chips[i];
+		if (!at91_gpio)
+			continue;
 
 		/*
 		 * GPIO controller are grouped on some SoC:
-- 
2.2.0

[PATCH 2/3] ARM: at91/dt: sama5d4: add pioD controller

[Ludovic Desroches]

PioD controller was not described in the device tree since we don't use
it. As pinctrl-at91 allows disabled gpio controllers in the device
tree, we can add it to complete the device description.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
---
 arch/arm/boot/dts/sama5d4.dtsi | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/arm/boot/dts/sama5d4.dtsi b/arch/arm/boot/dts/sama5d4.dtsi
index 1b0f30c..368973e 100644
--- a/arch/arm/boot/dts/sama5d4.dtsi
+++ b/arch/arm/boot/dts/sama5d4.dtsi
@@ -62,6 +62,7 @@
 		gpio0 = &pioA;
 		gpio1 = &pioB;
 		gpio2 = &pioC;
+		gpio3 = &pioD;
 		gpio4 = &pioE;
 		tcb0 = &tcb0;
 		tcb1 = &tcb1;
@@ -1111,6 +1112,18 @@
 					clocks = <&pioC_clk>;
 				};
 
+				pioD: gpio at fc068000 {
+					compatible = "atmel,at91sam9x5-gpio", "atmel,at91rm9200-gpio";
+					reg = <0xfc068000 0x100>;
+					interrupts = <5 IRQ_TYPE_LEVEL_HIGH 1>;
+					#gpio-cells = <2>;
+					gpio-controller;
+					interrupt-controller;
+					#interrupt-cells = <2>;
+					clocks = <&pioD_clk>;
+					status = "disabled";
+				};
+
 				pioE: gpio at fc06d000 {
 					compatible = "atmel,at91sam9x5-gpio", "atmel,at91rm9200-gpio";
 					reg = <0xfc06d000 0x100>;
-- 
2.2.0

[PATCH 3/3] MAINTAINERS: add maintainer for pinctrl-at91

[Ludovic Desroches]

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
---
 MAINTAINERS | 1 +
 1 file changed, 1 insertion(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index ddb9ac8..dfa702c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7405,6 +7405,7 @@ F:	include/linux/pinctrl/
 
 PIN CONTROLLER - ATMEL AT91
 M:	Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
+M:	Ludovic Desroches <ludovic.desroches@atmel.com>
 L:	linux-arm-kernel at lists.infradead.org (moderated for non-subscribers)
 S:	Maintained
 F:	drivers/pinctrl/pinctrl-at91.*
-- 
2.2.0

[PATCH 3/3] MAINTAINERS: add maintainer for pinctrl-at91

[Linus Walleij]

On Wed, Jan 14, 2015 at 11:08 AM, Ludovic Desroches
<ludovic.desroches@atmel.com> wrote:

> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>

The more maintainers the better.
Nicolas & J-C: can you ACK this?

Yours,
Linus Walleij

[PATCH 3/3] MAINTAINERS: add maintainer for pinctrl-at91

[Nicolas Ferre]

Le 19/01/2015 11:02, Linus Walleij a ?crit :
> On Wed, Jan 14, 2015 at 11:08 AM, Ludovic Desroches
> <ludovic.desroches@atmel.com> wrote:
> 
>> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
> 
> The more maintainers the better.
> Nicolas & J-C: can you ACK this?

Absolutely:
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

Bye,
-- 
Nicolas Ferre

[PATCH 3/3] MAINTAINERS: add maintainer for pinctrl-at91

[Jean-Christophe PLAGNIOL-VILLARD]

> On Jan 19, 2015, at 6:29 PM, Nicolas Ferre <nicolas.ferre@atmel.com> wrote:
> 
> Le 19/01/2015 11:02, Linus Walleij a ?crit :
>> On Wed, Jan 14, 2015 at 11:08 AM, Ludovic Desroches
>> <ludovic.desroches@atmel.com> wrote:
>> 
>>> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
>> 
>> The more maintainers the better.
>> Nicolas & J-C: can you ACK this?
> 
> Absolutely:
> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

I still maintain it does not see the need for 2 maintainers for a simple drivers

Nack for me

Best Regards,
J.
> 
> Bye,
> -- 
> Nicolas Ferre

[PATCH 3/3] MAINTAINERS: add maintainer for pinctrl-at91

[Linus Walleij]

On Mon, Jan 19, 2015 at 12:20 PM, Jean-Christophe PLAGNIOL-VILLARD
<plagnioj@jcrosoft.com> wrote:
>> On Jan 19, 2015, at 6:29 PM, Nicolas Ferre <nicolas.ferre@atmel.com> wrote:
>> Le 19/01/2015 11:02, Linus Walleij a ?crit :
>>> On Wed, Jan 14, 2015 at 11:08 AM, Ludovic Desroches
>>> <ludovic.desroches@atmel.com> wrote:
>>>
>>>> Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
>>>
>>> The more maintainers the better.
>>> Nicolas & J-C: can you ACK this?
>>
>> Absolutely:
>> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
>
> I still maintain it does not see the need for 2 maintainers for a simple drivers
>
> Nack for me

Cool, as subsystem maintainer had some delays in getting
reviews on patches for the AT91 drivers sometimes, but if you're
gonna be as quick in response as on this patch set then I can live
without a comaintainer I guess.

Yours,
Linus Walleij