[PATCH v4] video: fbdev: omapfb: lcd_ams_delta: use GPIO lookup table

Janusz Krzysztofik
2018-10-03T13:02:31Z

Now as Amstrad Delta board - the only user of this driver - provides
GPIO lookup tables, switch from GPIO numbers to GPIO descriptors and
use the table to locate required GPIO pins.

Declare static variables for storing GPIO descriptors and replace
gpio_ function calls with their gpiod_ equivalents. Move GPIO lookup
to the driver probe function so device initialization can be deferred
instead of aborted if a GPIO pin is not yet available.

Pin naming used by the driver should be followed while respective GPIO
lookup table is initialized by a board init code.

Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
---
Changelog:
v4:
- added Reviewed-by: Linus Walleij
- resubmitted as a standalone patch for inclusion via fbdev tree again

v3:
- rebased on top of v4.19-rc1 with all dependencies mentioned in v2
changelog satisfied

v2/v2:
- resubmitted in a series as [PATCH v2 1/3 v2] for inclusion via omap
tree

v2:
- removed problematic error code conversion no longer needed if used on
top of commit d08605a64e67 ("ARM: OMAP1: ams-delta: move late devices
back to init_machine") and commit 8853daf3b4ac ("gpiolib: Defer on
non-DT find_chip_by_name() failure") already in linux-next
- resubmitted as a standalone patch for inclusion via fbdev tree

Ininally submitted in a series as [PATCH 4/6]

drivers/video/fbdev/omap/lcd_ams_delta.c | 55 +++++++++++++-------------------
1 file changed, 22 insertions(+), 33 deletions(-)

diff --git a/drivers/video/fbdev/omap/lcd_ams_delta.c b/drivers/video/fbdev/omap/lcd_ams_delta.c
index e8c748a0dfe2..cddbd00cbf9f 100644
--- a/drivers/video/fbdev/omap/lcd_ams_delta.c
+++ b/drivers/video/fbdev/omap/lcd_ams_delta.c
@@ -24,11 +24,10 @@
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
#include <linux/lcd.h>
-#include <linux/gpio.h>

#include <mach/hardware.h>
-#include <mach/board-ams-delta.h>

#include "omapfb.h"

@@ -41,6 +40,8 @@
/* LCD class device section */

static int ams_delta_lcd;
+static struct gpio_desc *gpiod_vblen;
+static struct gpio_desc *gpiod_ndisp;

static int ams_delta_lcd_set_power(struct lcd_device *dev, int power)
{
@@ -99,41 +100,17 @@ static struct lcd_ops ams_delta_lcd_ops = {

/* omapfb panel section */

-static const struct gpio _gpios[] = {
- {
- .gpio = AMS_DELTA_GPIO_PIN_LCD_VBLEN,
- .flags = GPIOF_OUT_INIT_LOW,
- .label = "lcd_vblen",
- },
- {
- .gpio = AMS_DELTA_GPIO_PIN_LCD_NDISP,
- .flags = GPIOF_OUT_INIT_LOW,
- .label = "lcd_ndisp",
- },
-};
-
-static int ams_delta_panel_init(struct lcd_panel *panel,
- struct omapfb_device *fbdev)
-{
- return gpio_request_array(_gpios, ARRAY_SIZE(_gpios));
-}
-
-static void ams_delta_panel_cleanup(struct lcd_panel *panel)
-{
- gpio_free_array(_gpios, ARRAY_SIZE(_gpios));
-}
-
static int ams_delta_panel_enable(struct lcd_panel *panel)
{
- gpio_set_value(AMS_DELTA_GPIO_PIN_LCD_NDISP, 1);
- gpio_set_value(AMS_DELTA_GPIO_PIN_LCD_VBLEN, 1);
+ gpiod_set_value(gpiod_ndisp, 1);
+ gpiod_set_value(gpiod_vblen, 1);
return 0;
}

static void ams_delta_panel_disable(struct lcd_panel *panel)
{
- gpio_set_value(AMS_DELTA_GPIO_PIN_LCD_VBLEN, 0);
- gpio_set_value(AMS_DELTA_GPIO_PIN_LCD_NDISP, 0);
+ gpiod_set_value(gpiod_vblen, 0);
+ gpiod_set_value(gpiod_ndisp, 0);
}

static struct lcd_panel ams_delta_panel = {
@@ -154,8 +131,6 @@ static struct lcd_panel ams_delta_panel = {
.pcd = 0,
.acb = 37,

- .init = ams_delta_panel_init,
- .cleanup = ams_delta_panel_cleanup,
.enable = ams_delta_panel_enable,
.disable = ams_delta_panel_disable,
};
@@ -166,9 +141,23 @@ static struct lcd_panel ams_delta_panel = {
static int ams_delta_panel_probe(struct platform_device *pdev)
{
struct lcd_device *lcd_device = NULL;
-#ifdef CONFIG_LCD_CLASS_DEVICE
int ret;

+ gpiod_vblen = devm_gpiod_get(&pdev->dev, "vblen", GPIOD_OUT_LOW);
+ if (IS_ERR(gpiod_vblen)) {
+ ret = PTR_ERR(gpiod_vblen);
+ dev_err(&pdev->dev, "VBLEN GPIO request failed (%d)\n", ret);
+ return ret;
+ }
+
+ gpiod_ndisp = devm_gpiod_get(&pdev->dev, "ndisp", GPIOD_OUT_LOW);
+ if (IS_ERR(gpiod_ndisp)) {
+ ret = PTR_ERR(gpiod_ndisp);
+ dev_err(&pdev->dev, "NDISP GPIO request failed (%d)\n", ret);
+ return ret;
+ }
+
+#ifdef CONFIG_LCD_CLASS_DEVICE
lcd_device = lcd_device_register("omapfb", &pdev->dev, NULL,
&ams_delta_lcd_ops);

--
2.16.4