[PATCH v4 1/2] gpio: pca953x: Drop unneeded ACPI_PTR()

[PATCH v4 1/2] gpio: pca953x: Drop unneeded ACPI_PTR()

[Andy Shevchenko]

ACPI_PTR() becomes a no-op when !CONFIG_ACPI. This is not needed since
we always have ID table enabled. Moreover, in the mentioned case compiler
will complain about defined but not used variable.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v4: reincluded to the series since had not been applied yet
 drivers/gpio/gpio-pca953x.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index 4bb3d3524bc7..1fca8dd7824f 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -1176,7 +1176,7 @@ static struct i2c_driver pca953x_driver = {
 		.name	= "pca953x",
 		.pm	= &pca953x_pm_ops,
 		.of_match_table = pca953x_dt_ids,
-		.acpi_match_table = ACPI_PTR(pca953x_acpi_ids),
+		.acpi_match_table = pca953x_acpi_ids,
 	},
 	.probe		= pca953x_probe,
 	.remove		= pca953x_remove,
-- 
2.26.2

[PATCH v4 2/2] gpio: pca953x: Override IRQ for one of the expanders on Galileo Gen 2

[Andy Shevchenko]

ACPI table on Intel Galileo Gen 2 has wrong pin number for IRQ resource
of one of the I²C GPIO expanders. Since we know what that number is and
luckily have GPIO bases fixed for SoC's controllers, we may use a simple
DMI quirk to match the platform and retrieve GpioInt() pin on it for
the expander in question.

Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v4: addressed some concerns, made code compact (Mika)
 drivers/gpio/gpio-pca953x.c | 79 +++++++++++++++++++++++++++++++++++++
 1 file changed, 79 insertions(+)

diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index 1fca8dd7824f..e2f637dbc61a 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -107,6 +107,79 @@ static const struct i2c_device_id pca953x_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, pca953x_id);
 
+#ifdef CONFIG_GPIO_PCA953X_IRQ
+
+#include <linux/dmi.h>
+#include <linux/gpio.h>
+#include <linux/list.h>
+
+static const struct dmi_system_id pca953x_dmi_acpi_irq_info[] = {
+	{
+		/*
+		 * On Intel Galileo Gen 2 board the IRQ pin of one of
+		 * the I²C GPIO expanders, which has GpioInt() resource,
+		 * is provided as an absolute number instead of being
+		 * relative. Since first controller (gpio-sch.c) and
+		 * second (gpio-dwapb.c) are at the fixed bases, we may
+		 * safely refer to the number in the global space to get
+		 * an IRQ out of it.
+		 */
+		.matches = {
+			DMI_EXACT_MATCH(DMI_BOARD_NAME, "GalileoGen2"),
+		},
+	},
+	{}
+};
+
+#ifdef CONFIG_ACPI
+static int pca953x_acpi_get_pin(struct acpi_resource *ares, void *data)
+{
+	struct acpi_resource_gpio *agpio;
+	int *pin = data;
+
+	if (acpi_gpio_get_irq_resource(ares, &agpio))
+		*pin = agpio->pin_table[0];
+	return 1;
+}
+
+static int pca953x_acpi_find_pin(struct device *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+	int pin = -ENOENT, ret;
+	LIST_HEAD(r);
+
+	ret = acpi_dev_get_resources(adev, &r, pca953x_acpi_get_pin, &pin);
+	acpi_dev_free_resource_list(&r);
+	if (ret < 0)
+		return ret;
+
+	return pin;
+}
+#else
+static inline int pca953x_acpi_find_pin(struct device *dev) { return -ENXIO; }
+#endif
+
+static int pca953x_acpi_get_irq(struct device *dev)
+{
+	int pin, ret;
+
+	pin = pca953x_acpi_find_pin(dev);
+	if (pin < 0)
+		return pin;
+
+	dev_info(dev, "Applying ACPI interrupt quirk (GPIO %d)\n", pin);
+
+	if (!gpio_is_valid(pin))
+		return -EINVAL;
+
+	ret = gpio_request(pin, "pca953x interrupt");
+	if (ret)
+		return ret;
+
+	return gpio_to_irq(pin);
+}
+#endif
+
 static const struct acpi_device_id pca953x_acpi_ids[] = {
 	{ "INT3491", 16 | PCA953X_TYPE | PCA_LATCH_INT, },
 	{ }
@@ -752,6 +825,12 @@ static int pca953x_irq_setup(struct pca953x_chip *chip, int irq_base)
 	DECLARE_BITMAP(irq_stat, MAX_LINE);
 	int ret;
 
+	if (dmi_first_match(pca953x_dmi_acpi_irq_info)) {
+		ret = pca953x_acpi_get_irq(&client->dev);
+		if (ret > 0)
+			client->irq = ret;
+	}
+
 	if (!client->irq)
 		return 0;
 
-- 
2.26.2

Re: [PATCH v4 2/2] gpio: pca953x: Override IRQ for one of the expanders on Galileo Gen 2

[Mika Westerberg]

On Fri, May 29, 2020 at 04:30:54PM +0300, Andy Shevchenko wrote:
> ACPI table on Intel Galileo Gen 2 has wrong pin number for IRQ resource
> of one of the I²C GPIO expanders. Since we know what that number is and
> luckily have GPIO bases fixed for SoC's controllers, we may use a simple
> DMI quirk to match the platform and retrieve GpioInt() pin on it for
> the expander in question.
> 
> Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com>

I don't think this is needed since I did not suggest you to write this
patch. I only gave a couple of review comments.

> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Re: [PATCH v4 2/2] gpio: pca953x: Override IRQ for one of the expanders on Galileo Gen 2

[Andy Shevchenko]

On Mon, Jun 01, 2020 at 11:40:23AM +0300, Mika Westerberg wrote:
> On Fri, May 29, 2020 at 04:30:54PM +0300, Andy Shevchenko wrote:
> > ACPI table on Intel Galileo Gen 2 has wrong pin number for IRQ resource
> > of one of the I²C GPIO expanders. Since we know what that number is and
> > luckily have GPIO bases fixed for SoC's controllers, we may use a simple
> > DMI quirk to match the platform and retrieve GpioInt() pin on it for
> > the expander in question.
> > 
> > Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
> 
> I don't think this is needed since I did not suggest you to write this
> patch. I only gave a couple of review comments.

You suggested the way to avoid a quirk which brings us to almost rewritten
version of this. I think it's appropriate to put your tag, but if you insist,
I'll remove it.

> > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> 
> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Thank you!

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v4 2/2] gpio: pca953x: Override IRQ for one of the expanders on Galileo Gen 2

[Andy Shevchenko]

On Fri, May 29, 2020 at 04:30:54PM +0300, Andy Shevchenko wrote:
> ACPI table on Intel Galileo Gen 2 has wrong pin number for IRQ resource
> of one of the I²C GPIO expanders. Since we know what that number is and
> luckily have GPIO bases fixed for SoC's controllers, we may use a simple
> DMI quirk to match the platform and retrieve GpioInt() pin on it for
> the expander in question.

Since patch 1 from this series has been applied and I fixed few more bugs
I sent recently the series of four fixes with this one included as v1.

So, please, consider that one instead. I also applied Mika's tag.

-- 
With Best Regards,
Andy Shevchenko