[PATCH] Input: ads7846 - use managed allocated resources

From: Andi Shyti
Date: Thu Nov 09 2017 - 10:33:50 EST


Use managed allocated resources to simplify error handling during
probing.

Fix goto labels and remove function accordingly.

Signed-off-by: Andi Shyti <andi@xxxxxxxxxxx>
---
drivers/input/touchscreen/ads7846.c | 103 ++++++++++--------------------------
1 file changed, 28 insertions(+), 75 deletions(-)

diff --git a/drivers/input/touchscreen/ads7846.c b/drivers/input/touchscreen/ads7846.c
index a2f45aefce08..2bd7bfd0dc9f 100644
--- a/drivers/input/touchscreen/ads7846.c
+++ b/drivers/input/touchscreen/ads7846.c
@@ -527,19 +527,13 @@ static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts)
break;
}

- ts->hwmon = hwmon_device_register_with_groups(&spi->dev, spi->modalias,
- ts, ads7846_attr_groups);
+ ts->hwmon = devm_hwmon_device_register_with_groups(&spi->dev,
+ spi->modalias, ts,
+ ads7846_attr_groups);

return PTR_ERR_OR_ZERO(ts->hwmon);
}

-static void ads784x_hwmon_unregister(struct spi_device *spi,
- struct ads7846 *ts)
-{
- if (ts->hwmon)
- hwmon_device_unregister(ts->hwmon);
-}
-
#else
static inline int ads784x_hwmon_register(struct spi_device *spi,
struct ads7846 *ts)
@@ -547,10 +541,6 @@ static inline int ads784x_hwmon_register(struct spi_device *spi,
return 0;
}

-static inline void ads784x_hwmon_unregister(struct spi_device *spi,
- struct ads7846 *ts)
-{
-}
#endif

static ssize_t ads7846_pen_down_show(struct device *dev,
@@ -947,8 +937,8 @@ static int ads7846_setup_pendown(struct spi_device *spi,
ts->get_pendown_state = pdata->get_pendown_state;
} else if (gpio_is_valid(pdata->gpio_pendown)) {

- err = gpio_request_one(pdata->gpio_pendown, GPIOF_IN,
- "ads7846_pendown");
+ err = devm_gpio_request_one(&spi->dev, pdata->gpio_pendown,
+ GPIOF_IN, "ads7846_pendown");
if (err) {
dev_err(&spi->dev,
"failed to request/setup pendown GPIO%d: %d\n",
@@ -1283,13 +1273,13 @@ static int ads7846_probe(struct spi_device *spi)
if (err < 0)
return err;

- ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL);
- packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL);
- input_dev = input_allocate_device();
- if (!ts || !packet || !input_dev) {
- err = -ENOMEM;
- goto err_free_mem;
- }
+ ts = devm_kzalloc(&spi->dev, sizeof(struct ads7846), GFP_KERNEL);
+ packet = devm_kzalloc(&spi->dev,
+ sizeof(struct ads7846_packet),
+ GFP_KERNEL);
+ input_dev = devm_input_allocate_device(&spi->dev);
+ if (!ts || !packet || !input_dev)
+ return -ENOMEM;

spi_set_drvdata(spi, ts);

@@ -1303,10 +1293,8 @@ static int ads7846_probe(struct spi_device *spi)
pdata = dev_get_platdata(&spi->dev);
if (!pdata) {
pdata = ads7846_probe_dt(&spi->dev);
- if (IS_ERR(pdata)) {
- err = PTR_ERR(pdata);
- goto err_free_mem;
- }
+ if (IS_ERR(pdata))
+ return PTR_ERR(pdata);
}

ts->model = pdata->model ? : 7846;
@@ -1321,7 +1309,7 @@ static int ads7846_probe(struct spi_device *spi)
if (pdata->filter_init != NULL) {
err = pdata->filter_init(pdata, &ts->filter_data);
if (err < 0)
- goto err_free_mem;
+ return err;
}
ts->filter = pdata->filter;
ts->filter_cleanup = pdata->filter_cleanup;
@@ -1369,41 +1357,42 @@ static int ads7846_probe(struct spi_device *spi)

ads7846_setup_spi_msg(ts, pdata);

- ts->reg = regulator_get(&spi->dev, "vcc");
+ ts->reg = devm_regulator_get(&spi->dev, "vcc");
if (IS_ERR(ts->reg)) {
err = PTR_ERR(ts->reg);
dev_err(&spi->dev, "unable to get regulator: %d\n", err);
- goto err_free_gpio;
+ goto err_cleanup_filter;
}

err = regulator_enable(ts->reg);
if (err) {
dev_err(&spi->dev, "unable to enable regulator: %d\n", err);
- goto err_put_regulator;
+ goto err_cleanup_filter;
}

irq_flags = pdata->irq_flags ? : IRQF_TRIGGER_FALLING;
irq_flags |= IRQF_ONESHOT;

- err = request_threaded_irq(spi->irq, ads7846_hard_irq, ads7846_irq,
- irq_flags, spi->dev.driver->name, ts);
+ err = devm_request_threaded_irq(&spi->dev, spi->irq,
+ ads7846_hard_irq, ads7846_irq,
+ irq_flags, spi->dev.driver->name, ts);
if (err && !pdata->irq_flags) {
dev_info(&spi->dev,
"trying pin change workaround on irq %d\n", spi->irq);
irq_flags |= IRQF_TRIGGER_RISING;
- err = request_threaded_irq(spi->irq,
+ err = devm_request_threaded_irq(&spi->dev, spi->irq,
ads7846_hard_irq, ads7846_irq,
irq_flags, spi->dev.driver->name, ts);
}

if (err) {
dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
- goto err_disable_regulator;
+ goto err_cleanup_filter;
}

err = ads784x_hwmon_register(spi, ts);
if (err)
- goto err_free_irq;
+ goto err_cleanup_filter;

dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq);

@@ -1416,13 +1405,13 @@ static int ads7846_probe(struct spi_device *spi)
else
(void) ads7846_read12_ser(&spi->dev, READ_12BIT_SER(vaux));

- err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group);
+ err = devm_device_add_group(&spi->dev, &ads784x_attr_group);
if (err)
- goto err_remove_hwmon;
+ goto err_cleanup_filter;

err = input_register_device(input_dev);
if (err)
- goto err_remove_attr_group;
+ goto err_cleanup_filter;

device_init_wakeup(&spi->dev, pdata->wakeup);

@@ -1435,26 +1424,10 @@ static int ads7846_probe(struct spi_device *spi)

return 0;

- err_remove_attr_group:
- sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group);
- err_remove_hwmon:
- ads784x_hwmon_unregister(spi, ts);
- err_free_irq:
- free_irq(spi->irq, ts);
- err_disable_regulator:
- regulator_disable(ts->reg);
- err_put_regulator:
- regulator_put(ts->reg);
- err_free_gpio:
- if (!ts->get_pendown_state)
- gpio_free(ts->gpio_pendown);
err_cleanup_filter:
if (ts->filter_cleanup)
ts->filter_cleanup(ts->filter_data);
- err_free_mem:
- input_free_device(input_dev);
- kfree(packet);
- kfree(ts);
+
return err;
}

@@ -1462,31 +1435,11 @@ static int ads7846_remove(struct spi_device *spi)
{
struct ads7846 *ts = spi_get_drvdata(spi);

- sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group);
-
ads7846_disable(ts);
- free_irq(ts->spi->irq, ts);
-
- input_unregister_device(ts->input);
-
- ads784x_hwmon_unregister(spi, ts);
-
- regulator_put(ts->reg);
-
- if (!ts->get_pendown_state) {
- /*
- * If we are not using specialized pendown method we must
- * have been relying on gpio we set up ourselves.
- */
- gpio_free(ts->gpio_pendown);
- }

if (ts->filter_cleanup)
ts->filter_cleanup(ts->filter_data);

- kfree(ts->packet);
- kfree(ts);
-
dev_dbg(&spi->dev, "unregistered touchscreen\n");

return 0;
--
2.15.0