diff mbox series

[v2] pinctrl: bcm63268: add gpio function

Message ID 20241224103645.1709996-1-noltari@gmail.com
State New
Headers show
Series [v2] pinctrl: bcm63268: add gpio function | expand

Commit Message

Álvaro Fernández Rojas Dec. 24, 2024, 10:36 a.m. UTC 
From: Kyle Hendry <kylehendrydev@gmail.com>

There is no guarantee that the bootloader will leave the pin configuration
in a known default state, so pinctrl needs to be explicitly set in some
cases. This patch adds a gpio function for drivers that need it, i.e.
gpio-leds.

Signed-off-by: Kyle Hendry <kylehendrydev@gmail.com>
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
---
 drivers/pinctrl/bcm/pinctrl-bcm63268.c | 71 +++++++++++++++++++++++++-
 1 file changed, 70 insertions(+), 1 deletion(-)

Comments

Jonas Gorski Dec. 30, 2024, 4:42 p.m. UTC | #1 
Hi,

On Tue, Dec 24, 2024 at 11:41 AM Álvaro Fernández Rojas
<noltari@gmail.com> wrote:
>
> From: Kyle Hendry <kylehendrydev@gmail.com>
>
> There is no guarantee that the bootloader will leave the pin configuration
> in a known default state, so pinctrl needs to be explicitly set in some
> cases. This patch adds a gpio function for drivers that need it, i.e.
> gpio-leds.
>
> Signed-off-by: Kyle Hendry <kylehendrydev@gmail.com>
> Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>


bcm63268-pinctrl implements pinmux_ops::gpio_request_enable(), which
should automatically set any requested GPIO pin to the GPIO function,
so explicitly requesting the gpio function for a pin should not be
needed. Is this not enough?

Best Regards,
Jonas
Kyle Hendry Jan. 3, 2025, 3:04 a.m. UTC | #2 
On 2024-12-30 08:42, Jonas Gorski wrote:
> Hi,
>
> On Tue, Dec 24, 2024 at 11:41 AM Álvaro Fernández Rojas
> <noltari@gmail.com> wrote:
>> From: Kyle Hendry <kylehendrydev@gmail.com>
>>
>> There is no guarantee that the bootloader will leave the pin configuration
>> in a known default state, so pinctrl needs to be explicitly set in some
>> cases. This patch adds a gpio function for drivers that need it, i.e.
>> gpio-leds.
>>
>> Signed-off-by: Kyle Hendry <kylehendrydev@gmail.com>
>> Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
>
> bcm63268-pinctrl implements pinmux_ops::gpio_request_enable(), which
> should automatically set any requested GPIO pin to the GPIO function,
> so explicitly requesting the gpio function for a pin should not be
> needed. Is this not enough?
>
> Best Regards,
> Jonas
>
>
I assumed that as well, but nothing I tried worked with gpio-leds.
gpiochip_generic_request() does call gpio_request_enable(), but gpio-leds
uses devm_fwnode_gpiod_get() which looks like a different code path. The
only place it seems to be configuring the gpio is in create_gpio_led()
where it needs a pinctl node in the device tree. That's just my reading
of the code, though. I haven't set up a ftrace to verify it.

Best Regards,
Kyle
diff mbox series

Patch

diff --git a/drivers/pinctrl/bcm/pinctrl-bcm63268.c b/drivers/pinctrl/bcm/pinctrl-bcm63268.c
index 80c2fc55ffa2..a98f57e64d1e 100644
--- a/drivers/pinctrl/bcm/pinctrl-bcm63268.c
+++ b/drivers/pinctrl/bcm/pinctrl-bcm63268.c
@@ -34,6 +34,7 @@ 
 #define  BCM63268_BASEMODE_VDSL_PHY_3	BIT(9) /* GPIOs 26/27 */
 
 enum bcm63268_pinctrl_reg {
+	BCM63268_NONE,
 	BCM63268_LEDCTRL,
 	BCM63268_MODE,
 	BCM63268_CTRL,
@@ -242,6 +243,61 @@  static struct pingroup bcm63268_groups[] = {
 	BCM_PIN_GROUP(vdsl_phy3_grp),
 };
 
+static const char * const gpio_groups[] = {
+	"gpio0",
+	"gpio1",
+	"gpio2",
+	"gpio3",
+	"gpio4",
+	"gpio5",
+	"gpio6",
+	"gpio7",
+	"gpio8",
+	"gpio9",
+	"gpio10",
+	"gpio11",
+	"gpio12",
+	"gpio13",
+	"gpio14",
+	"gpio15",
+	"gpio16",
+	"gpio17",
+	"gpio18",
+	"gpio19",
+	"gpio20",
+	"gpio21",
+	"gpio22",
+	"gpio23",
+	"gpio24",
+	"gpio25",
+	"gpio26",
+	"gpio27",
+	"gpio28",
+	"gpio29",
+	"gpio30",
+	"gpio31",
+	"gpio32",
+	"gpio33",
+	"gpio34",
+	"gpio35",
+	"gpio36",
+	"gpio37",
+	"gpio38",
+	"gpio39",
+	"gpio40",
+	"gpio41",
+	"gpio42",
+	"gpio43",
+	"gpio44",
+	"gpio45",
+	"gpio46",
+	"gpio47",
+	"gpio48",
+	"gpio49",
+	"gpio50",
+	"gpio51",
+};
+
 static const char * const led_groups[] = {
 	"gpio0",
 	"gpio1",
@@ -394,6 +450,14 @@  static const char * const vdsl_phy_override_3_groups[] = {
 	"vdsl_phy_override_3_grp",
 };
 
+#define BCM63268_GPIO_FUN(n)				\
+	{						\
+		.name = #n,				\
+		.groups = n##_groups,			\
+		.num_groups = ARRAY_SIZE(n##_groups),	\
+		.reg = BCM63268_NONE,			\
+	}
+
 #define BCM63268_LED_FUN(n)				\
 	{						\
 		.name = #n,				\
@@ -428,6 +492,7 @@  static const char * const vdsl_phy_override_3_groups[] = {
 	}
 
 static const struct bcm63268_function bcm63268_funcs[] = {
+	BCM63268_GPIO_FUN(gpio),
 	BCM63268_LED_FUN(led),
 	BCM63268_MODE_FUN(serial_led_clk),
 	BCM63268_MODE_FUN(serial_led_data),
@@ -542,6 +607,9 @@  static int bcm63268_pinctrl_set_mux(struct pinctrl_dev *pctldev,
 		bcm63268_set_gpio(pc, pg->pins[i]);
 
 	switch (f->reg) {
+	case BCM63268_NONE:
+		reg = 0;
+		break;
 	case BCM63268_LEDCTRL:
 		reg = BCM63268_LED_REG;
 		mask = BIT(pg->pins[0]);
@@ -567,7 +635,8 @@  static int bcm63268_pinctrl_set_mux(struct pinctrl_dev *pctldev,
 		return -EINVAL;
 	}
 
-	regmap_update_bits(pc->regs, reg, mask, val);
+	if (reg)
+		regmap_update_bits(pc->regs, reg, mask, val);
 
 	return 0;
 }