[PATCH 2/4] Input: rotary_encoder - convert to use gpiod API

From: Dmitry Torokhov
Date: Mon Jan 18 2016 - 12:43:38 EST


Instead of using old GPIO API, let's switch to GPIOD API, which
automatically handles polarity.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
---
arch/arm/mach-pxa/raumfeld.c | 21 +++++++++--
drivers/input/misc/rotary_encoder.c | 73 +++++++++++++++++--------------------
include/linux/rotary_encoder.h | 4 --
3 files changed, 50 insertions(+), 48 deletions(-)

diff --git a/arch/arm/mach-pxa/raumfeld.c b/arch/arm/mach-pxa/raumfeld.c
index 36571a9..d156f79 100644
--- a/arch/arm/mach-pxa/raumfeld.c
+++ b/arch/arm/mach-pxa/raumfeld.c
@@ -21,6 +21,7 @@
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
+#include <linux/gpio/machine.h>
#include <linux/smsc911x.h>
#include <linux/input.h>
#include <linux/rotary_encoder.h>
@@ -366,14 +367,21 @@ static struct pxaohci_platform_data raumfeld_ohci_info = {
* Rotary encoder input device
*/

+static struct gpiod_lookup_table raumfeld_rotary_gpios_table = {
+ .dev_id = "rotary-encoder",
+ .table = {
+ GPIO_LOOKUP_IDX("gpio-0",
+ GPIO_VOLENC_A, NULL, 0, GPIO_ACTIVE_LOW),
+ GPIO_LOOKUP_IDX("gpio-0",
+ GPIO_VOLENC_B, NULL, 1, GPIO_ACTIVE_HIGH),
+ { },
+ },
+};
+
static struct rotary_encoder_platform_data raumfeld_rotary_encoder_info = {
.steps = 24,
.axis = REL_X,
.relative_axis = 1,
- .gpio_a = GPIO_VOLENC_A,
- .gpio_b = GPIO_VOLENC_B,
- .inverted_a = 1,
- .inverted_b = 0,
};

static struct platform_device rotary_encoder_device = {
@@ -1051,7 +1059,10 @@ static void __init raumfeld_controller_init(void)
int ret;

pxa3xx_mfp_config(ARRAY_AND_SIZE(raumfeld_controller_pin_config));
+
+ gpiod_add_lookup_table(&raumfeld_rotary_gpios_table);
platform_device_register(&rotary_encoder_device);
+
spi_register_board_info(ARRAY_AND_SIZE(controller_spi_devices));
i2c_register_board_info(0, &raumfeld_controller_i2c_board_info, 1);

@@ -1086,6 +1097,8 @@ static void __init raumfeld_speaker_init(void)
i2c_register_board_info(0, &raumfeld_connector_i2c_board_info, 1);

platform_device_register(&smc91x_device);
+
+ gpiod_add_lookup_table(&raumfeld_rotary_gpios_table);
platform_device_register(&rotary_encoder_device);

raumfeld_audio_init();
diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/rotary_encoder.c
index b9a86ca..e913bfb64 100644
--- a/drivers/input/misc/rotary_encoder.c
+++ b/drivers/input/misc/rotary_encoder.c
@@ -20,12 +20,11 @@
#include <linux/input.h>
#include <linux/device.h>
#include <linux/platform_device.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <linux/rotary_encoder.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_platform.h>
-#include <linux/of_gpio.h>
#include <linux/pm.h>

#define DRV_NAME "rotary-encoder"
@@ -38,6 +37,9 @@ struct rotary_encoder {
unsigned int axis;
unsigned int pos;

+ struct gpio_desc *gpio_a;
+ struct gpio_desc *gpio_b;
+
unsigned int irq_a;
unsigned int irq_b;

@@ -47,13 +49,10 @@ struct rotary_encoder {
char last_stable;
};

-static int rotary_encoder_get_state(const struct rotary_encoder_platform_data *pdata)
+static int rotary_encoder_get_state(struct rotary_encoder *encoder)
{
- int a = !!gpio_get_value_cansleep(pdata->gpio_a);
- int b = !!gpio_get_value_cansleep(pdata->gpio_b);
-
- a ^= pdata->inverted_a;
- b ^= pdata->inverted_b;
+ int a = !!gpiod_get_value_cansleep(encoder->gpio_a);
+ int b = !!gpiod_get_value_cansleep(encoder->gpio_b);

return ((a << 1) | b);
}
@@ -97,7 +96,7 @@ static irqreturn_t rotary_encoder_irq(int irq, void *dev_id)

mutex_lock(&encoder->access_mutex);

- state = rotary_encoder_get_state(encoder->pdata);
+ state = rotary_encoder_get_state(encoder);

switch (state) {
case 0x0:
@@ -130,7 +129,7 @@ static irqreturn_t rotary_encoder_half_period_irq(int irq, void *dev_id)

mutex_lock(&encoder->access_mutex);

- state = rotary_encoder_get_state(encoder->pdata);
+ state = rotary_encoder_get_state(encoder);

switch (state) {
case 0x00:
@@ -160,7 +159,7 @@ static irqreturn_t rotary_encoder_quarter_period_irq(int irq, void *dev_id)

mutex_lock(&encoder->access_mutex);

- state = rotary_encoder_get_state(encoder->pdata);
+ state = rotary_encoder_get_state(encoder);

/*
* We encode the previous and the current state using a byte.
@@ -232,12 +231,6 @@ static struct rotary_encoder_platform_data *rotary_encoder_parse_dt(struct devic
of_property_read_u32(np, "rotary-encoder,steps", &pdata->steps);
of_property_read_u32(np, "linux,axis", &pdata->axis);

- pdata->gpio_a = of_get_gpio_flags(np, 0, &flags);
- pdata->inverted_a = flags & OF_GPIO_ACTIVE_LOW;
-
- pdata->gpio_b = of_get_gpio_flags(np, 1, &flags);
- pdata->inverted_b = flags & OF_GPIO_ACTIVE_LOW;
-
pdata->relative_axis =
of_property_read_bool(np, "rotary-encoder,relative-axis");
pdata->rollover = of_property_read_bool(np, "rotary-encoder,rollover");
@@ -294,14 +287,32 @@ static int rotary_encoder_probe(struct platform_device *pdev)
if (!encoder)
return -ENOMEM;

+ mutex_init(&encoder->access_mutex);
+ encoder->pdata = pdata;
+
+ encoder->gpio_a = devm_gpiod_get_index(dev, NULL, 0, GPIOD_IN);
+ if (IS_ERR(encoder->gpio_a)) {
+ err = PTR_ERR(encoder->gpio_a);
+ dev_err(dev, "unable to get GPIO at index 0: %d\n", err);
+ return err;
+ }
+
+ encoder->irq_a = gpiod_to_irq(encoder->gpio_a);
+
+ encoder->gpio_b = devm_gpiod_get_index(dev, NULL, 1, GPIOD_IN);
+ if (IS_ERR(encoder->gpio_b)) {
+ err = PTR_ERR(encoder->gpio_b);
+ dev_err(dev, "unable to get GPIO at index 1: %d\n", err);
+ return err;
+ }
+
+ encoder->irq_b = gpiod_to_irq(encoder->gpio_b);
+
input = devm_input_allocate_device(dev);
if (!input)
return -ENOMEM;

- mutex_init(&encoder->access_mutex);
-
encoder->input = input;
- encoder->pdata = pdata;

input->name = pdev->name;
input->id.bustype = BUS_HOST;
@@ -316,32 +327,14 @@ static int rotary_encoder_probe(struct platform_device *pdev)
pdata->axis, 0, pdata->steps, 0, 1);
}

- /* request the GPIOs */
- err = devm_gpio_request_one(dev, pdata->gpio_a, GPIOF_IN,
- dev_name(dev));
- if (err) {
- dev_err(dev, "unable to request GPIO %d\n", pdata->gpio_a);
- return err;
- }
-
- err = devm_gpio_request_one(dev, pdata->gpio_b, GPIOF_IN,
- dev_name(dev));
- if (err) {
- dev_err(dev, "unable to request GPIO %d\n", pdata->gpio_b);
- return err;
- }
-
- encoder->irq_a = gpio_to_irq(pdata->gpio_a);
- encoder->irq_b = gpio_to_irq(pdata->gpio_b);
-
switch (pdata->steps_per_period) {
case 4:
handler = &rotary_encoder_quarter_period_irq;
- encoder->last_stable = rotary_encoder_get_state(pdata);
+ encoder->last_stable = rotary_encoder_get_state(encoder);
break;
case 2:
handler = &rotary_encoder_half_period_irq;
- encoder->last_stable = rotary_encoder_get_state(pdata);
+ encoder->last_stable = rotary_encoder_get_state(encoder);
break;
case 1:
handler = &rotary_encoder_irq;
diff --git a/include/linux/rotary_encoder.h b/include/linux/rotary_encoder.h
index fe3dc64..4536c81 100644
--- a/include/linux/rotary_encoder.h
+++ b/include/linux/rotary_encoder.h
@@ -4,10 +4,6 @@
struct rotary_encoder_platform_data {
unsigned int steps;
unsigned int axis;
- unsigned int gpio_a;
- unsigned int gpio_b;
- unsigned int inverted_a;
- unsigned int inverted_b;
unsigned int steps_per_period;
bool relative_axis;
bool rollover;
--
2.6.0.rc2.230.g3dd15c0