48 lines
1.1 KiB
ReStructuredText
48 lines
1.1 KiB
ReStructuredText
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=====================
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Kernel driver w1-gpio
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=====================
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Author: Ville Syrjala <syrjala@sci.fi>
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Description
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-----------
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GPIO 1-wire bus master driver. The driver uses the GPIO API to control the
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wire and the GPIO pin can be specified using GPIO machine descriptor tables.
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It is also possible to define the master using device tree, see
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Documentation/devicetree/bindings/w1/w1-gpio.yaml
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Example (mach-at91)
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-------------------
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::
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#include <linux/gpio/machine.h>
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#include <linux/w1-gpio.h>
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static struct gpiod_lookup_table foo_w1_gpiod_table = {
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.dev_id = "w1-gpio",
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.table = {
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GPIO_LOOKUP_IDX("at91-gpio", AT91_PIN_PB20, NULL, 0,
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GPIO_ACTIVE_HIGH|GPIO_OPEN_DRAIN),
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},
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};
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static struct w1_gpio_platform_data foo_w1_gpio_pdata = {
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.ext_pullup_enable_pin = -EINVAL,
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};
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static struct platform_device foo_w1_device = {
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.name = "w1-gpio",
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.id = -1,
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.dev.platform_data = &foo_w1_gpio_pdata,
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};
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...
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at91_set_GPIO_periph(foo_w1_gpio_pdata.pin, 1);
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at91_set_multi_drive(foo_w1_gpio_pdata.pin, 1);
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gpiod_add_lookup_table(&foo_w1_gpiod_table);
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platform_device_register(&foo_w1_device);
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