diff options
Diffstat (limited to 'drivers/w1/masters/w1-gpio.c')
| -rw-r--r-- | drivers/w1/masters/w1-gpio.c | 158 |
1 files changed, 121 insertions, 37 deletions
diff --git a/drivers/w1/masters/w1-gpio.c b/drivers/w1/masters/w1-gpio.c index fcbe742188a..1d111e56c8c 100644 --- a/drivers/w1/masters/w1-gpio.c +++ b/drivers/w1/masters/w1-gpio.c @@ -13,11 +13,35 @@ #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/w1-gpio.h> +#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" -#include <asm/gpio.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) { @@ -43,22 +67,91 @@ static u8 w1_gpio_read_bit(void *data) return gpio_get_value(pdata->pin) ? 1 : 0; } -static int __init w1_gpio_probe(struct platform_device *pdev) +#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 = dev_get_platdata(&pdev->dev); + struct device_node *np = pdev->dev.of_node; + int gpio; + + 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; + + 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; +} + +static int 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; - if (!pdata) + if (of_have_populated_dt()) { + err = w1_gpio_probe_dt(pdev); + if (err < 0) + return err; + } + + pdata = dev_get_platdata(&pdev->dev); + + 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 = 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; master->read_bit = w1_gpio_read_bit; @@ -69,38 +162,38 @@ 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; + if (err) { + dev_err(&pdev->dev, "w1_add_master device failed\n"); + return err; + } 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: - 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); + 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); return 0; } @@ -109,7 +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); @@ -119,7 +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); @@ -136,24 +229,15 @@ 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), + .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>"); |
