[PATCH 3/4] input: keyboard: gpio_keys_polled: use gpio lookup table

Enrico Weigelt, metux IT consult
2019-04-16T19:57:24Z

Support the recently introduced gpio lookup tables for
attaching to gpio lines. So, harcoded gpio numbers aren't
needed anymore.

Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: linux-input@vger.kernel.org
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
---
drivers/input/keyboard/gpio_keys_polled.c | 167 +++++++++++++++++++++---------
1 file changed, 119 insertions(+), 48 deletions(-)

diff --git a/drivers/input/keyboard/gpio_keys_polled.c b/drivers/input/keyboard/gpio_keys_polled.c
index 3312186..3f773b2 100644
--- a/drivers/input/keyboard/gpio_keys_polled.c
+++ b/drivers/input/keyboard/gpio_keys_polled.c
@@ -24,6 +24,7 @@
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
+#include <linux/gpio/machine.h>
#include <linux/gpio_keys.h>
#include <linux/property.h>

@@ -227,6 +228,119 @@ static void gpio_keys_polled_set_abs_params(struct input_dev *input,
};
MODULE_DEVICE_TABLE(of, gpio_keys_polled_of_match);

+static struct gpio_desc *gpio_keys_polled_get_gpiod_fwnode(
+ struct device *dev,
+ int idx,
+ const char *desc)
+{
+ struct gpio_desc *gpiod;
+ struct fwnode_handle *child;
+ int x;
+
+ /* get the idx'th child node */
+ child = device_get_next_child_node(dev, NULL);
+ while (child && x) {
+ child = device_get_next_child_node(dev, child);
+ x--;
+ }
+
+ if (!child) {
+ dev_err(dev, "missing oftree child node #%d\n", idx);
+ return ERR_PTR(-EINVAL);
+ }
+
+ gpiod = devm_fwnode_get_gpiod_from_child(dev,
+ NULL,
+ child,
+ GPIOD_IN,
+ desc);
+ if (IS_ERR(gpiod)) {
+ if (PTR_ERR(gpiod) != -EPROBE_DEFER)
+ dev_err(dev,
+ "failed to get gpio: %ld\n",
+ PTR_ERR(gpiod));
+ fwnode_handle_put(child);
+ return gpiod;
+ }
+
+ return gpiod;
+}
+
+static struct gpio_desc *gpio_keys_polled_get_gpiod_legacy(
+ struct device *dev,
+ int idx,
+ const struct gpio_keys_button *button)
+{
+ /*
+ * Legacy GPIO number so request the GPIO here and
+ * convert it to descriptor.
+ */
+ unsigned int flags = GPIOF_IN;
+ struct gpio_desc *gpiod;
+ int error;
+
+ dev_info(dev, "hardcoded gpio IDs are deprecated.\n");
+
+ if (button->active_low)
+ flags |= GPIOF_ACTIVE_LOW;
+
+ error = devm_gpio_request_one(dev, button->gpio,
+ flags, button->desc ? : DRV_NAME);
+ if (error) {
+ dev_err(dev,
+ "unable to claim gpio %u, err=%d\n",
+ button->gpio, error);
+ return ERR_PTR(error);
+ }
+
+ gpiod = gpio_to_desc(button->gpio);
+ if (!gpiod) {
+ dev_err(dev,
+ "unable to convert gpio %u to descriptor\n",
+ button->gpio);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return gpiod;
+}
+
+static struct gpio_desc *gpio_keys_polled_get_gpiod(
+ struct device *dev,
+ int idx,
+ const struct gpio_keys_button *button)
+{
+ struct gpio_desc *gpiod = NULL;
+ int error;
+
+ /* No legacy static platform data - use oftree */
+ if (!dev_get_platdata(dev)) {
+ return gpio_keys_polled_get_gpiod_fwnode(
+ dev, idx, button->desc);
+ }
+
+ gpiod = devm_gpiod_get_index(dev, NULL, idx, GPIOF_IN);
+
+ if (!IS_ERR(gpiod)) {
+ dev_info(dev, "picked gpiod idx %d from gpio table\n", idx);
+ gpiod_set_consumer_name(gpiod, button->desc ? : DRV_NAME);
+ return gpiod;
+ }
+
+ if (PTR_ERR(gpiod) != -ENOENT) {
+ dev_err(dev, "failed fetching gpiod #%d: %d\n",
+ idx, PTR_ERR(gpiod));
+ return gpiod;
+ }
+
+ /* Use legacy gpio id, if defined */
+ if (gpio_is_valid(button->gpio)) {
+ return gpio_keys_polled_get_gpiod_legacy(
+ dev, idx, button);
+ }
+
+ return ERR_PTR(-ENOENT);
+}
+
static int gpio_keys_polled_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -291,57 +405,14 @@ static int gpio_keys_polled_probe(struct platform_device *pdev)

if (button->wakeup) {
dev_err(dev, DRV_NAME " does not support wakeup\n");
- fwnode_handle_put(child);
return -EINVAL;
}

- if (!dev_get_platdata(dev)) {
- /* No legacy static platform data */
- child = device_get_next_child_node(dev, child);
- if (!child) {
- dev_err(dev, "missing child device node\n");
- return -EINVAL;
- }
-
- bdata->gpiod = devm_fwnode_get_gpiod_from_child(dev,
- NULL, child,
- GPIOD_IN,
- button->desc);
- if (IS_ERR(bdata->gpiod)) {
- error = PTR_ERR(bdata->gpiod);
- if (error != -EPROBE_DEFER)
- dev_err(dev,
- "failed to get gpio: %d\n",
- error);
- fwnode_handle_put(child);
- return error;
- }
- } else if (gpio_is_valid(button->gpio)) {
- /*
- * Legacy GPIO number so request the GPIO here and
- * convert it to descriptor.
- */
- unsigned flags = GPIOF_IN;
-
- if (button->active_low)
- flags |= GPIOF_ACTIVE_LOW;
-
- error = devm_gpio_request_one(dev, button->gpio,
- flags, button->desc ? : DRV_NAME);
- if (error) {
- dev_err(dev,
- "unable to claim gpio %u, err=%d\n",
- button->gpio, error);
- return error;
- }
-
- bdata->gpiod = gpio_to_desc(button->gpio);
- if (!bdata->gpiod) {
- dev_err(dev,
- "unable to convert gpio %u to descriptor\n",
- button->gpio);
- return -EINVAL;
- }
+ bdata->gpiod = gpio_keys_polled_get_gpiod(dev, i, button);
+
+ if (IS_ERR(bdata->gpiod)) {
+ dev_err(dev, "failed to fetch gpiod #%d\n", i);
+ return PTR_ERR(bdata->gpiod);
}

bdata->last_state = -1;
--
1.9.1