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path: root/drivers/w1/masters/w1-gpio.c
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Diffstat (limited to 'drivers/w1/masters/w1-gpio.c')
-rw-r--r--drivers/w1/masters/w1-gpio.c145
1 files changed, 84 insertions, 61 deletions
diff --git a/drivers/w1/masters/w1-gpio.c b/drivers/w1/masters/w1-gpio.c
index 6012c4ea320..1d111e56c8c 100644
--- a/drivers/w1/masters/w1-gpio.c
+++ b/drivers/w1/masters/w1-gpio.c
@@ -16,10 +16,33 @@
#include <linux/gpio.h>
#include <linux/of_platform.h>
#include <linux/of_gpio.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/delay.h>
#include "../w1.h"
#include "../w1_int.h"
+static u8 w1_gpio_set_pullup(void *data, int delay)
+{
+ struct w1_gpio_platform_data *pdata = data;
+
+ if (delay) {
+ pdata->pullup_duration = delay;
+ } else {
+ if (pdata->pullup_duration) {
+ gpio_direction_output(pdata->pin, 1);
+
+ msleep(pdata->pullup_duration);
+
+ gpio_direction_input(pdata->pin);
+ }
+ pdata->pullup_duration = 0;
+ }
+
+ return 0;
+}
+
static void w1_gpio_write_bit_dir(void *data, u8 bit)
{
struct w1_gpio_platform_data *pdata = data;
@@ -44,22 +67,19 @@ static u8 w1_gpio_read_bit(void *data)
return gpio_get_value(pdata->pin) ? 1 : 0;
}
-#ifdef CONFIG_OF
+#if defined(CONFIG_OF)
static struct of_device_id w1_gpio_dt_ids[] = {
{ .compatible = "w1-gpio" },
{}
};
MODULE_DEVICE_TABLE(of, w1_gpio_dt_ids);
+#endif
static int w1_gpio_probe_dt(struct platform_device *pdev)
{
- struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
+ struct w1_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
struct device_node *np = pdev->dev.of_node;
- const struct of_device_id *of_id =
- of_match_device(w1_gpio_dt_ids, &pdev->dev);
-
- if (!of_id)
- return 0;
+ int gpio;
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
@@ -68,47 +88,69 @@ static int w1_gpio_probe_dt(struct platform_device *pdev)
if (of_get_property(np, "linux,open-drain", NULL))
pdata->is_open_drain = 1;
- pdata->pin = of_get_gpio(np, 0);
- pdata->ext_pullup_enable_pin = of_get_gpio(np, 1);
+ gpio = of_get_gpio(np, 0);
+ if (gpio < 0) {
+ if (gpio != -EPROBE_DEFER)
+ dev_err(&pdev->dev,
+ "Failed to parse gpio property for data pin (%d)\n",
+ gpio);
+
+ return gpio;
+ }
+ pdata->pin = gpio;
+
+ gpio = of_get_gpio(np, 1);
+ if (gpio == -EPROBE_DEFER)
+ return gpio;
+ /* ignore other errors as the pullup gpio is optional */
+ pdata->ext_pullup_enable_pin = gpio;
+
pdev->dev.platform_data = pdata;
return 0;
}
-#else
-static int w1_gpio_probe_dt(struct platform_device *pdev)
-{
- return 0;
-}
-#endif
-static int __init w1_gpio_probe(struct platform_device *pdev)
+static int w1_gpio_probe(struct platform_device *pdev)
{
struct w1_bus_master *master;
struct w1_gpio_platform_data *pdata;
int err;
- err = w1_gpio_probe_dt(pdev);
- if (err < 0)
- return err;
+ if (of_have_populated_dt()) {
+ err = w1_gpio_probe_dt(pdev);
+ if (err < 0)
+ return err;
+ }
- pdata = pdev->dev.platform_data;
+ pdata = dev_get_platdata(&pdev->dev);
- if (!pdata)
+ if (!pdata) {
+ dev_err(&pdev->dev, "No configuration data\n");
return -ENXIO;
+ }
- master = kzalloc(sizeof(struct w1_bus_master), GFP_KERNEL);
- if (!master)
+ master = devm_kzalloc(&pdev->dev, sizeof(struct w1_bus_master),
+ GFP_KERNEL);
+ if (!master) {
+ dev_err(&pdev->dev, "Out of memory\n");
return -ENOMEM;
+ }
- err = gpio_request(pdata->pin, "w1");
- if (err)
- goto free_master;
+ err = devm_gpio_request(&pdev->dev, pdata->pin, "w1");
+ if (err) {
+ dev_err(&pdev->dev, "gpio_request (pin) failed\n");
+ return err;
+ }
if (gpio_is_valid(pdata->ext_pullup_enable_pin)) {
- err = gpio_request_one(pdata->ext_pullup_enable_pin,
- GPIOF_INIT_LOW, "w1 pullup");
- if (err < 0)
- goto free_gpio;
+ err = devm_gpio_request_one(&pdev->dev,
+ pdata->ext_pullup_enable_pin, GPIOF_INIT_LOW,
+ "w1 pullup");
+ if (err < 0) {
+ dev_err(&pdev->dev, "gpio_request_one "
+ "(ext_pullup_enable_pin) failed\n");
+ return err;
+ }
}
master->data = pdata;
@@ -120,11 +162,14 @@ static int __init w1_gpio_probe(struct platform_device *pdev)
} else {
gpio_direction_input(pdata->pin);
master->write_bit = w1_gpio_write_bit_dir;
+ master->set_pullup = w1_gpio_set_pullup;
}
err = w1_add_master_device(master);
- if (err)
- goto free_gpio_ext_pu;
+ if (err) {
+ dev_err(&pdev->dev, "w1_add_master device failed\n");
+ return err;
+ }
if (pdata->enable_external_pullup)
pdata->enable_external_pullup(1);
@@ -135,22 +180,12 @@ static int __init w1_gpio_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, master);
return 0;
-
- free_gpio_ext_pu:
- if (gpio_is_valid(pdata->ext_pullup_enable_pin))
- gpio_free(pdata->ext_pullup_enable_pin);
- free_gpio:
- gpio_free(pdata->pin);
- free_master:
- kfree(master);
-
- return err;
}
-static int __exit w1_gpio_remove(struct platform_device *pdev)
+static int w1_gpio_remove(struct platform_device *pdev)
{
struct w1_bus_master *master = platform_get_drvdata(pdev);
- struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
+ struct w1_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
if (pdata->enable_external_pullup)
pdata->enable_external_pullup(0);
@@ -159,8 +194,6 @@ static int __exit w1_gpio_remove(struct platform_device *pdev)
gpio_set_value(pdata->ext_pullup_enable_pin, 0);
w1_remove_master_device(master);
- gpio_free(pdata->pin);
- kfree(master);
return 0;
}
@@ -169,7 +202,7 @@ static int __exit w1_gpio_remove(struct platform_device *pdev)
static int w1_gpio_suspend(struct platform_device *pdev, pm_message_t state)
{
- struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
+ struct w1_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
if (pdata->enable_external_pullup)
pdata->enable_external_pullup(0);
@@ -179,7 +212,7 @@ static int w1_gpio_suspend(struct platform_device *pdev, pm_message_t state)
static int w1_gpio_resume(struct platform_device *pdev)
{
- struct w1_gpio_platform_data *pdata = pdev->dev.platform_data;
+ struct w1_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
if (pdata->enable_external_pullup)
pdata->enable_external_pullup(1);
@@ -198,23 +231,13 @@ static struct platform_driver w1_gpio_driver = {
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(w1_gpio_dt_ids),
},
- .remove = __exit_p(w1_gpio_remove),
+ .probe = w1_gpio_probe,
+ .remove = w1_gpio_remove,
.suspend = w1_gpio_suspend,
.resume = w1_gpio_resume,
};
-static int __init w1_gpio_init(void)
-{
- return platform_driver_probe(&w1_gpio_driver, w1_gpio_probe);
-}
-
-static void __exit w1_gpio_exit(void)
-{
- platform_driver_unregister(&w1_gpio_driver);
-}
-
-module_init(w1_gpio_init);
-module_exit(w1_gpio_exit);
+module_platform_driver(w1_gpio_driver);
MODULE_DESCRIPTION("GPIO w1 bus master driver");
MODULE_AUTHOR("Ville Syrjala <syrjala@sci.fi>");
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-11-09 18:20:00 +0000