1 // SPDX-License-Identifier: GPL-2.0
39 	struct device *dev = &pdev->dev;  in ds2404_gpio_map()
41 	/* This will de-assert RESET, declare this GPIO as GPIOD_ACTIVE_LOW */  in ds2404_gpio_map()
42 	chip->rst_gpiod = devm_gpiod_get(dev, "rst", GPIOD_OUT_LOW);  in ds2404_gpio_map()
43 	if (IS_ERR(chip->rst_gpiod))  in ds2404_gpio_map()
44 		return PTR_ERR(chip->rst_gpiod);  in ds2404_gpio_map()
46 	chip->clk_gpiod = devm_gpiod_get(dev, "clk", GPIOD_OUT_HIGH);  in ds2404_gpio_map()
47 	if (IS_ERR(chip->clk_gpiod))  in ds2404_gpio_map()
48 		return PTR_ERR(chip->clk_gpiod);  in ds2404_gpio_map()
50 	chip->dq_gpiod = devm_gpiod_get(dev, "dq", GPIOD_ASIS);  in ds2404_gpio_map()
51 	if (IS_ERR(chip->dq_gpiod))  in ds2404_gpio_map()
52 		return PTR_ERR(chip->dq_gpiod);  in ds2404_gpio_map()
59 	gpiod_set_value(chip->rst_gpiod, 1);  in ds2404_reset()
61 	gpiod_set_value(chip->rst_gpiod, 0);  in ds2404_reset()
62 	gpiod_set_value(chip->clk_gpiod, 0);  in ds2404_reset()
63 	gpiod_direction_output(chip->dq_gpiod, 0);  in ds2404_reset()
71 	gpiod_direction_output(chip->dq_gpiod, 1);  in ds2404_write_byte()
73 		gpiod_set_value(chip->dq_gpiod, byte & (1 << i));  in ds2404_write_byte()
75 		gpiod_set_value(chip->clk_gpiod, 1);  in ds2404_write_byte()
77 		gpiod_set_value(chip->clk_gpiod, 0);  in ds2404_write_byte()
87 	gpiod_direction_input(chip->dq_gpiod);  in ds2404_read_byte()
90 		gpiod_set_value(chip->clk_gpiod, 0);  in ds2404_read_byte()
92 		if (gpiod_get_value(chip->dq_gpiod))  in ds2404_read_byte()
94 		gpiod_set_value(chip->clk_gpiod, 1);  in ds2404_read_byte()
107 	while (length--)  in ds2404_read_memory()
115 	u8 ta01, ta02, es;  in ds2404_write_memory()  local
130 	es = ds2404_read_byte(chip);  in ds2404_write_memory()
134 			dev_err(chip->dev, "read invalid data\n");  in ds2404_write_memory()
143 	ds2404_write_byte(chip, es);  in ds2404_write_memory()
145 	while (gpiod_get_value(chip->dq_gpiod))  in ds2404_write_memory()
151 	u8 in[1] = { 0x10 }; /* enable oscillator */  in ds2404_enable_osc()
185 	int retval = -EBUSY;  in rtc_probe()
187 	chip = devm_kzalloc(&pdev->dev, sizeof(struct ds2404), GFP_KERNEL);  in rtc_probe()
189 		return -ENOMEM;  in rtc_probe()
191 	chip->dev = &pdev->dev;  in rtc_probe()
193 	chip->rtc = devm_rtc_allocate_device(&pdev->dev);  in rtc_probe()
194 	if (IS_ERR(chip->rtc))  in rtc_probe()
195 		return PTR_ERR(chip->rtc);  in rtc_probe()
203 	chip->rtc->ops = &ds2404_rtc_ops;  in rtc_probe()
204 	chip->rtc->range_max = U32_MAX;  in rtc_probe()
206 	retval = devm_rtc_register_device(chip->rtc);  in rtc_probe()