36 static int ds2404_gpio_map(struct ds2404 *chip, struct platform_device *pdev)  in ds2404_gpio_map()  argument
41 	chip->rst_gpiod = devm_gpiod_get(dev, "rst", GPIOD_OUT_LOW);  in ds2404_gpio_map()
42 	if (IS_ERR(chip->rst_gpiod))  in ds2404_gpio_map()
43 		return PTR_ERR(chip->rst_gpiod);  in ds2404_gpio_map()
45 	chip->clk_gpiod = devm_gpiod_get(dev, "clk", GPIOD_OUT_HIGH);  in ds2404_gpio_map()
46 	if (IS_ERR(chip->clk_gpiod))  in ds2404_gpio_map()
47 		return PTR_ERR(chip->clk_gpiod);  in ds2404_gpio_map()
49 	chip->dq_gpiod = devm_gpiod_get(dev, "dq", GPIOD_ASIS);  in ds2404_gpio_map()
50 	if (IS_ERR(chip->dq_gpiod))  in ds2404_gpio_map()
51 		return PTR_ERR(chip->dq_gpiod);  in ds2404_gpio_map()
56 static void ds2404_reset(struct ds2404 *chip)  in ds2404_reset()  argument
58 	gpiod_set_value(chip->rst_gpiod, 1);  in ds2404_reset()
60 	gpiod_set_value(chip->rst_gpiod, 0);  in ds2404_reset()
61 	gpiod_set_value(chip->clk_gpiod, 0);  in ds2404_reset()
62 	gpiod_direction_output(chip->dq_gpiod, 0);  in ds2404_reset()
66 static void ds2404_write_byte(struct ds2404 *chip, u8 byte)  in ds2404_write_byte()  argument
70 	gpiod_direction_output(chip->dq_gpiod, 1);  in ds2404_write_byte()
72 		gpiod_set_value(chip->dq_gpiod, byte & (1 << i));  in ds2404_write_byte()
74 		gpiod_set_value(chip->clk_gpiod, 1);  in ds2404_write_byte()
76 		gpiod_set_value(chip->clk_gpiod, 0);  in ds2404_write_byte()
81 static u8 ds2404_read_byte(struct ds2404 *chip)  in ds2404_read_byte()  argument
86 	gpiod_direction_input(chip->dq_gpiod);  in ds2404_read_byte()
89 		gpiod_set_value(chip->clk_gpiod, 0);  in ds2404_read_byte()
91 		if (gpiod_get_value(chip->dq_gpiod))  in ds2404_read_byte()
93 		gpiod_set_value(chip->clk_gpiod, 1);  in ds2404_read_byte()
99 static void ds2404_read_memory(struct ds2404 *chip, u16 offset,  in ds2404_read_memory()  argument
102 	ds2404_reset(chip);  in ds2404_read_memory()
103 	ds2404_write_byte(chip, DS2404_READ_MEMORY_CMD);  in ds2404_read_memory()
104 	ds2404_write_byte(chip, offset & 0xff);  in ds2404_read_memory()
105 	ds2404_write_byte(chip, (offset >> 8) & 0xff);  in ds2404_read_memory()
107 		*out++ = ds2404_read_byte(chip);  in ds2404_read_memory()
110 static void ds2404_write_memory(struct ds2404 *chip, u16 offset,  in ds2404_write_memory()  argument
116 	ds2404_reset(chip);  in ds2404_write_memory()
117 	ds2404_write_byte(chip, DS2404_WRITE_SCRATCHPAD_CMD);  in ds2404_write_memory()
118 	ds2404_write_byte(chip, offset & 0xff);  in ds2404_write_memory()
119 	ds2404_write_byte(chip, (offset >> 8) & 0xff);  in ds2404_write_memory()
122 		ds2404_write_byte(chip, out[i]);  in ds2404_write_memory()
124 	ds2404_reset(chip);  in ds2404_write_memory()
125 	ds2404_write_byte(chip, DS2404_READ_SCRATCHPAD_CMD);  in ds2404_write_memory()
127 	ta01 = ds2404_read_byte(chip);  in ds2404_write_memory()
128 	ta02 = ds2404_read_byte(chip);  in ds2404_write_memory()
129 	es = ds2404_read_byte(chip);  in ds2404_write_memory()
132 		if (out[i] != ds2404_read_byte(chip)) {  in ds2404_write_memory()
133 			dev_err(chip->dev, "read invalid data\n");  in ds2404_write_memory()
138 	ds2404_reset(chip);  in ds2404_write_memory()
139 	ds2404_write_byte(chip, DS2404_COPY_SCRATCHPAD_CMD);  in ds2404_write_memory()
140 	ds2404_write_byte(chip, ta01);  in ds2404_write_memory()
141 	ds2404_write_byte(chip, ta02);  in ds2404_write_memory()
142 	ds2404_write_byte(chip, es);  in ds2404_write_memory()
144 	while (gpiod_get_value(chip->dq_gpiod))  in ds2404_write_memory()
148 static void ds2404_enable_osc(struct ds2404 *chip)  in ds2404_enable_osc()  argument
152 	ds2404_write_memory(chip, 0x201, 1, in);  in ds2404_enable_osc()
157 	struct ds2404 *chip = dev_get_drvdata(dev);  in ds2404_read_time()  local
161 	ds2404_read_memory(chip, 0x203, 4, (u8 *)&hw_time);  in ds2404_read_time()
170 	struct ds2404 *chip = dev_get_drvdata(dev);  in ds2404_set_time()  local
172 	ds2404_write_memory(chip, 0x203, 4, (u8 *)&time);  in ds2404_set_time()
183 	struct ds2404 *chip;  in rtc_probe()  local
187 	chip = devm_kzalloc(&pdev->dev, sizeof(struct ds2404), GFP_KERNEL);  in rtc_probe()
188 	if (!chip)  in rtc_probe()
191 	chip->dev = &pdev->dev;  in rtc_probe()
197 	retval = ds2404_gpio_map(chip, pdev);  in rtc_probe()
201 	platform_set_drvdata(pdev, chip);  in rtc_probe()
210 	ds2404_enable_osc(chip);  in rtc_probe()