* [PATCH 1/2] gpio: wm831x: use the new open drain callback
@ 2016-04-10 13:12 Linus Walleij
2016-04-11 10:59 ` Mark Brown
0 siblings, 1 reply; 4+ messages in thread
From: Linus Walleij @ 2016-04-10 13:12 UTC (permalink / raw)
To: linux-gpio, Alexandre Courbot
Cc: Linus Walleij, patches, Mark Brown, Charles Keepax
The WM831x GPIOs clearly have a dedicated open drain control
register. Implement support for controlling this from GPIO
descriptor tables or other hardware descriptions such as
device tree by implementing the .set_single_ended() callback.
Before this patch, lines requesting open drain will just be
switched to input mode by the framework, thus emulating open
drain. But the hardware can do the real thing, so let's
support that.
As part of this, rename the debugfs string for output mode
from "CMOS" to "push-pull" because it is the term used in
the framework to signify a tomem-pole CMOS output.
Cc: patches@opensource.wolfsonmicro.com
Cc: Mark Brown <broonie@kernel.org>
Cc: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
drivers/gpio/gpio-wm831x.c | 22 +++++++++++++++++++++-
1 file changed, 21 insertions(+), 1 deletion(-)
diff --git a/drivers/gpio/gpio-wm831x.c b/drivers/gpio/gpio-wm831x.c
index 18cb0f534b91..c16c6fc3683c 100644
--- a/drivers/gpio/gpio-wm831x.c
+++ b/drivers/gpio/gpio-wm831x.c
@@ -132,6 +132,25 @@ static int wm831x_gpio_set_debounce(struct gpio_chip *chip, unsigned offset,
return wm831x_set_bits(wm831x, reg, WM831X_GPN_FN_MASK, fn);
}
+static int wm831x_set_single_ended(struct gpio_chip *chip,
+ unsigned int offset,
+ enum single_ended_mode mode)
+{
+ struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
+ struct wm831x *wm831x = wm831x_gpio->wm831x;
+ int reg = WM831X_GPIO1_CONTROL + offset;
+
+ if (mode == LINE_MODE_OPEN_DRAIN)
+ return wm831x_set_bits(wm831x, reg,
+ WM831X_GPN_OD_MASK, WM831X_GPN_OD);
+
+ if (mode == LINE_MODE_PUSH_PULL)
+ return wm831x_set_bits(wm831x, reg,
+ WM831X_GPN_OD_MASK, 0);
+
+ return -ENOTSUPP;
+}
+
#ifdef CONFIG_DEBUG_FS
static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
@@ -216,7 +235,7 @@ static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
pull,
powerdomain,
reg & WM831X_GPN_POL ? "" : " inverted",
- reg & WM831X_GPN_OD ? "open-drain" : "CMOS",
+ reg & WM831X_GPN_OD ? "open-drain" : "push-pull",
tristated ? " tristated" : "",
reg);
}
@@ -234,6 +253,7 @@ static struct gpio_chip template_chip = {
.set = wm831x_gpio_set,
.to_irq = wm831x_gpio_to_irq,
.set_debounce = wm831x_gpio_set_debounce,
+ .set_single_ended = wm831x_set_single_ended,
.dbg_show = wm831x_gpio_dbg_show,
.can_sleep = true,
};
--
2.4.3
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 1/2] gpio: wm831x: use the new open drain callback
2016-04-10 13:12 Linus Walleij
@ 2016-04-11 10:59 ` Mark Brown
0 siblings, 0 replies; 4+ messages in thread
From: Mark Brown @ 2016-04-11 10:59 UTC (permalink / raw)
To: Linus Walleij; +Cc: linux-gpio, Alexandre Courbot, patches, Charles Keepax
[-- Attachment #1: Type: text/plain, Size: 492 bytes --]
On Sun, Apr 10, 2016 at 03:12:19PM +0200, Linus Walleij wrote:
> + int reg = WM831X_GPIO1_CONTROL + offset;
> +
> + if (mode == LINE_MODE_OPEN_DRAIN)
> + return wm831x_set_bits(wm831x, reg,
> + WM831X_GPN_OD_MASK, WM831X_GPN_OD);
> +
> + if (mode == LINE_MODE_PUSH_PULL)
> + return wm831x_set_bits(wm831x, reg,
> + WM831X_GPN_OD_MASK, 0);
> +
> + return -ENOTSUPP;
This looks like it'd be better written as a switch statement (it's more
natural and less error prone).
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^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH 1/2] gpio: wm831x: use the new open drain callback
@ 2016-04-12 7:29 Linus Walleij
2016-04-12 7:59 ` Charles Keepax
0 siblings, 1 reply; 4+ messages in thread
From: Linus Walleij @ 2016-04-12 7:29 UTC (permalink / raw)
To: linux-gpio, Alexandre Courbot
Cc: Linus Walleij, patches, Mark Brown, Charles Keepax
The WM831x GPIOs clearly have a dedicated open drain control
register. Implement support for controlling this from GPIO
descriptor tables or other hardware descriptions such as
device tree by implementing the .set_single_ended() callback.
Before this patch, lines requesting open drain will just be
switched to input mode by the framework, thus emulating open
drain. But the hardware can do the real thing, so let's
support that.
As part of this, rename the debugfs string for output mode
from "CMOS" to "push-pull" because it is the term used in
the framework to signify a tomem-pole CMOS output.
Cc: patches@opensource.wolfsonmicro.com
Cc: Mark Brown <broonie@kernel.org>
Cc: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
ChangeLog v1->v2:
- Use a switch() statement rather than if-constructions
---
drivers/gpio/gpio-wm831x.c | 25 ++++++++++++++++++++++++-
1 file changed, 24 insertions(+), 1 deletion(-)
diff --git a/drivers/gpio/gpio-wm831x.c b/drivers/gpio/gpio-wm831x.c
index 18cb0f534b91..41ec7834059a 100644
--- a/drivers/gpio/gpio-wm831x.c
+++ b/drivers/gpio/gpio-wm831x.c
@@ -132,6 +132,28 @@ static int wm831x_gpio_set_debounce(struct gpio_chip *chip, unsigned offset,
return wm831x_set_bits(wm831x, reg, WM831X_GPN_FN_MASK, fn);
}
+static int wm831x_set_single_ended(struct gpio_chip *chip,
+ unsigned int offset,
+ enum single_ended_mode mode)
+{
+ struct wm831x_gpio *wm831x_gpio = gpiochip_get_data(chip);
+ struct wm831x *wm831x = wm831x_gpio->wm831x;
+ int reg = WM831X_GPIO1_CONTROL + offset;
+
+ switch (mode) {
+ case LINE_MODE_OPEN_DRAIN:
+ return wm831x_set_bits(wm831x, reg,
+ WM831X_GPN_OD_MASK, WM831X_GPN_OD);
+ case LINE_MODE_PUSH_PULL:
+ return wm831x_set_bits(wm831x, reg,
+ WM831X_GPN_OD_MASK, 0);
+ default:
+ break;
+ }
+
+ return -ENOTSUPP;
+}
+
#ifdef CONFIG_DEBUG_FS
static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
@@ -216,7 +238,7 @@ static void wm831x_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
pull,
powerdomain,
reg & WM831X_GPN_POL ? "" : " inverted",
- reg & WM831X_GPN_OD ? "open-drain" : "CMOS",
+ reg & WM831X_GPN_OD ? "open-drain" : "push-pull",
tristated ? " tristated" : "",
reg);
}
@@ -234,6 +256,7 @@ static struct gpio_chip template_chip = {
.set = wm831x_gpio_set,
.to_irq = wm831x_gpio_to_irq,
.set_debounce = wm831x_gpio_set_debounce,
+ .set_single_ended = wm831x_set_single_ended,
.dbg_show = wm831x_gpio_dbg_show,
.can_sleep = true,
};
--
2.4.3
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH 1/2] gpio: wm831x: use the new open drain callback
2016-04-12 7:29 [PATCH 1/2] gpio: wm831x: use the new open drain callback Linus Walleij
@ 2016-04-12 7:59 ` Charles Keepax
0 siblings, 0 replies; 4+ messages in thread
From: Charles Keepax @ 2016-04-12 7:59 UTC (permalink / raw)
To: Linus Walleij; +Cc: linux-gpio, Alexandre Courbot, patches, Mark Brown
On Tue, Apr 12, 2016 at 09:29:40AM +0200, Linus Walleij wrote:
> The WM831x GPIOs clearly have a dedicated open drain control
> register. Implement support for controlling this from GPIO
> descriptor tables or other hardware descriptions such as
> device tree by implementing the .set_single_ended() callback.
>
> Before this patch, lines requesting open drain will just be
> switched to input mode by the framework, thus emulating open
> drain. But the hardware can do the real thing, so let's
> support that.
>
> As part of this, rename the debugfs string for output mode
> from "CMOS" to "push-pull" because it is the term used in
> the framework to signify a tomem-pole CMOS output.
>
> Cc: patches@opensource.wolfsonmicro.com
> Cc: Mark Brown <broonie@kernel.org>
> Cc: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Thanks,
Charles
^ permalink raw reply [flat|nested] 4+ messages in thread
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