[PATCH v2] fbdev/media: Use GPIO descriptors for VIA GPIO

* [PATCH v2] fbdev/media: Use GPIO descriptors for VIA GPIO
@ 2023-06-13  6:33 Linus Walleij
  2023-06-19  6:17 ` Helge Deller
  0 siblings, 1 reply; 2+ messages in thread
From: Linus Walleij @ 2023-06-13  6:33 UTC (permalink / raw)
  To: Jonathan Corbet, Florian Tobias Schandinat,
	Mauro Carvalho Chehab, Helge Deller
  Cc: linux-fbdev, dri-devel, linux-media

The VIA fbdev exposes a custom GPIO chip for its GPIOs, these
are in turn looked up the camera driver using a custom API.

Drop the custom API, provide a look-up table and convert to
GPIO descriptors. Note proper polarity on the RESET line.

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
---
ChangeLog v1->v2:
- Fix a missed include (I guess I had an old compiled
  object that just worked...)

I don't know about the merge path for this one, let's merge
it in the provider (fbdev) if possible.
This looks like OLPC stuff.
---
 drivers/media/platform/via/via-camera.c       | 51 ++++++++-----------
 drivers/video/fbdev/via/via-core.c            |  2 +-
 drivers/video/fbdev/via/via-gpio.c            | 28 +++++-----
 .../video/fbdev/via}/via-gpio.h               |  1 -
 4 files changed, 35 insertions(+), 47 deletions(-)
 rename {include/linux => drivers/video/fbdev/via}/via-gpio.h (84%)

diff --git a/drivers/media/platform/via/via-camera.c b/drivers/media/platform/via/via-camera.c
index 450254403fa8..4cb8f29e2f14 100644
--- a/drivers/media/platform/via/via-camera.c
+++ b/drivers/media/platform/via/via-camera.c
@@ -11,7 +11,7 @@
 #include <linux/device.h>
 #include <linux/list.h>
 #include <linux/pci.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/videodev2.h>
@@ -26,7 +26,6 @@
 #include <linux/dma-mapping.h>
 #include <linux/pm_qos.h>
 #include <linux/via-core.h>
-#include <linux/via-gpio.h>
 #include <linux/via_i2c.h>
 
 #ifdef CONFIG_X86
@@ -71,8 +70,8 @@ struct via_camera {
 	/*
 	 * GPIO info for power/reset management
 	 */
-	int power_gpio;
-	int reset_gpio;
+	struct gpio_desc *power_gpio;
+	struct gpio_desc *reset_gpio;
 	/*
 	 * I/O memory stuff.
 	 */
@@ -180,27 +179,19 @@ static struct via_format *via_find_format(u32 pixelformat)
  */
 static int via_sensor_power_setup(struct via_camera *cam)
 {
-	int ret;
+	struct device *dev = &cam->platdev->dev;
+
+	cam->power_gpio = devm_gpiod_get(dev, "VGPIO3", GPIOD_OUT_LOW);
+	if (IS_ERR(cam->power_gpio))
+		return dev_err_probe(dev, PTR_ERR(cam->power_gpio),
+				     "failed to get power GPIO");
+
+	/* Request the reset line asserted */
+	cam->reset_gpio = devm_gpiod_get(dev, "VGPIO2", GPIOD_OUT_HIGH);
+	if (IS_ERR(cam->reset_gpio))
+		return dev_err_probe(dev, PTR_ERR(cam->reset_gpio),
+				     "failed to get reset GPIO");
 
-	cam->power_gpio = viafb_gpio_lookup("VGPIO3");
-	cam->reset_gpio = viafb_gpio_lookup("VGPIO2");
-	if (!gpio_is_valid(cam->power_gpio) || !gpio_is_valid(cam->reset_gpio)) {
-		dev_err(&cam->platdev->dev, "Unable to find GPIO lines\n");
-		return -EINVAL;
-	}
-	ret = gpio_request(cam->power_gpio, "viafb-camera");
-	if (ret) {
-		dev_err(&cam->platdev->dev, "Unable to request power GPIO\n");
-		return ret;
-	}
-	ret = gpio_request(cam->reset_gpio, "viafb-camera");
-	if (ret) {
-		dev_err(&cam->platdev->dev, "Unable to request reset GPIO\n");
-		gpio_free(cam->power_gpio);
-		return ret;
-	}
-	gpio_direction_output(cam->power_gpio, 0);
-	gpio_direction_output(cam->reset_gpio, 0);
 	return 0;
 }
 
@@ -209,25 +200,23 @@ static int via_sensor_power_setup(struct via_camera *cam)
  */
 static void via_sensor_power_up(struct via_camera *cam)
 {
-	gpio_set_value(cam->power_gpio, 1);
-	gpio_set_value(cam->reset_gpio, 0);
+	gpiod_set_value(cam->power_gpio, 1);
+	gpiod_set_value(cam->reset_gpio, 1);
 	msleep(20);  /* Probably excessive */
-	gpio_set_value(cam->reset_gpio, 1);
+	gpiod_set_value(cam->reset_gpio, 0);
 	msleep(20);
 }
 
 static void via_sensor_power_down(struct via_camera *cam)
 {
-	gpio_set_value(cam->power_gpio, 0);
-	gpio_set_value(cam->reset_gpio, 0);
+	gpiod_set_value(cam->power_gpio, 0);
+	gpiod_set_value(cam->reset_gpio, 1);
 }
 
 
 static void via_sensor_power_release(struct via_camera *cam)
 {
 	via_sensor_power_down(cam);
-	gpio_free(cam->power_gpio);
-	gpio_free(cam->reset_gpio);
 }
 
 /* --------------------------------------------------------------------------*/
diff --git a/drivers/video/fbdev/via/via-core.c b/drivers/video/fbdev/via/via-core.c
index 2c1803eb196f..908524a74a38 100644
--- a/drivers/video/fbdev/via/via-core.c
+++ b/drivers/video/fbdev/via/via-core.c
@@ -11,7 +11,7 @@
 #include <linux/aperture.h>
 #include <linux/via-core.h>
 #include <linux/via_i2c.h>
-#include <linux/via-gpio.h>
+#include "via-gpio.h"
 #include "global.h"
 
 #include <linux/module.h>
diff --git a/drivers/video/fbdev/via/via-gpio.c b/drivers/video/fbdev/via/via-gpio.c
index f1b670397c02..2719943c06f4 100644
--- a/drivers/video/fbdev/via/via-gpio.c
+++ b/drivers/video/fbdev/via/via-gpio.c
@@ -7,10 +7,11 @@
 
 #include <linux/spinlock.h>
 #include <linux/gpio/driver.h>
+#include <linux/gpio/machine.h>
 #include <linux/platform_device.h>
 #include <linux/via-core.h>
-#include <linux/via-gpio.h>
 #include <linux/export.h>
+#include "via-gpio.h"
 
 /*
  * The ports we know about.  Note that the port-25 gpios are not
@@ -189,19 +190,14 @@ static struct viafb_pm_hooks viafb_gpio_pm_hooks = {
 };
 #endif /* CONFIG_PM */
 
-/*
- * Look up a specific gpio and return the number it was assigned.
- */
-int viafb_gpio_lookup(const char *name)
-{
-	int i;
-
-	for (i = 0; i < viafb_gpio_config.gpio_chip.ngpio; i++)
-		if (!strcmp(name, viafb_gpio_config.active_gpios[i]->vg_name))
-			return viafb_gpio_config.gpio_chip.base + i;
-	return -1;
-}
-EXPORT_SYMBOL_GPL(viafb_gpio_lookup);
+static struct gpiod_lookup_table viafb_gpio_table = {
+	.dev_id = "viafb-camera",
+	.table = {
+		GPIO_LOOKUP("via-gpio", 2, "VGPIO2", GPIO_ACTIVE_LOW),
+		GPIO_LOOKUP("via-gpio", 3, "VGPIO3", GPIO_ACTIVE_HIGH),
+		{ }
+	},
+};
 
 /*
  * Platform device stuff.
@@ -249,12 +245,16 @@ static int viafb_gpio_probe(struct platform_device *platdev)
 	 * Get registered.
 	 */
 	viafb_gpio_config.gpio_chip.base = -1;  /* Dynamic */
+	viafb_gpio_config.gpio_chip.label = "via-gpio";
 	ret = gpiochip_add_data(&viafb_gpio_config.gpio_chip,
 				&viafb_gpio_config);
 	if (ret) {
 		printk(KERN_ERR "viafb: failed to add gpios (%d)\n", ret);
 		viafb_gpio_config.gpio_chip.ngpio = 0;
 	}
+
+	gpiod_add_lookup_table(&viafb_gpio_table);
+
 #ifdef CONFIG_PM
 	viafb_pm_register(&viafb_gpio_pm_hooks);
 #endif
diff --git a/include/linux/via-gpio.h b/drivers/video/fbdev/via/via-gpio.h
similarity index 84%
rename from include/linux/via-gpio.h
rename to drivers/video/fbdev/via/via-gpio.h
index ac34668fd442..2ffedf282f7e 100644
--- a/include/linux/via-gpio.h
+++ b/drivers/video/fbdev/via/via-gpio.h
@@ -8,7 +8,6 @@
 #ifndef __VIA_GPIO_H__
 #define __VIA_GPIO_H__
 
-extern int viafb_gpio_lookup(const char *name);
 extern int viafb_gpio_init(void);
 extern void viafb_gpio_exit(void);
 #endif
-- 
2.34.1


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