diff options
Diffstat (limited to 'drivers/w1/masters/w1-gpio.c')
| -rw-r--r-- | drivers/w1/masters/w1-gpio.c | 66 |
1 files changed, 64 insertions, 2 deletions
diff --git a/drivers/w1/masters/w1-gpio.c b/drivers/w1/masters/w1-gpio.c index df600d14974d..6012c4ea3206 100644 --- a/drivers/w1/masters/w1-gpio.c +++ b/drivers/w1/masters/w1-gpio.c @@ -14,6 +14,8 @@ #include <linux/slab.h> #include <linux/w1-gpio.h> #include <linux/gpio.h> +#include <linux/of_platform.h> +#include <linux/of_gpio.h> #include "../w1.h" #include "../w1_int.h" @@ -42,12 +44,55 @@ static u8 w1_gpio_read_bit(void *data) return gpio_get_value(pdata->pin) ? 1 : 0; } +#ifdef CONFIG_OF +static struct of_device_id w1_gpio_dt_ids[] = { + { .compatible = "w1-gpio" }, + {} +}; +MODULE_DEVICE_TABLE(of, w1_gpio_dt_ids); + +static int w1_gpio_probe_dt(struct platform_device *pdev) +{ + struct w1_gpio_platform_data *pdata = pdev->dev.platform_data; + 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; + + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + 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); + 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) { struct w1_bus_master *master; - struct w1_gpio_platform_data *pdata = pdev->dev.platform_data; + struct w1_gpio_platform_data *pdata; int err; + err = w1_gpio_probe_dt(pdev); + if (err < 0) + return err; + + pdata = pdev->dev.platform_data; + if (!pdata) return -ENXIO; @@ -59,6 +104,13 @@ static int __init w1_gpio_probe(struct platform_device *pdev) if (err) goto free_master; + 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; + } + master->data = pdata; master->read_bit = w1_gpio_read_bit; @@ -72,15 +124,21 @@ static int __init w1_gpio_probe(struct platform_device *pdev) err = w1_add_master_device(master); if (err) - goto free_gpio; + goto free_gpio_ext_pu; if (pdata->enable_external_pullup) pdata->enable_external_pullup(1); + if (gpio_is_valid(pdata->ext_pullup_enable_pin)) + gpio_set_value(pdata->ext_pullup_enable_pin, 1); + 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: @@ -97,6 +155,9 @@ static int __exit w1_gpio_remove(struct platform_device *pdev) if (pdata->enable_external_pullup) pdata->enable_external_pullup(0); + if (gpio_is_valid(pdata->ext_pullup_enable_pin)) + gpio_set_value(pdata->ext_pullup_enable_pin, 0); + w1_remove_master_device(master); gpio_free(pdata->pin); kfree(master); @@ -135,6 +196,7 @@ static struct platform_driver w1_gpio_driver = { .driver = { .name = "w1-gpio", .owner = THIS_MODULE, + .of_match_table = of_match_ptr(w1_gpio_dt_ids), }, .remove = __exit_p(w1_gpio_remove), .suspend = w1_gpio_suspend, |