4  * Copyright (C) 2004-2010 Nokia Corporation
40 	struct gpio_desc *clk;  member
42 	struct gpio_desc *sel;  member
46  * cbus_send_bit - sends one bit over the bus
52 	gpiod_set_value(host->dat, bit ? 1 : 0);  in cbus_send_bit()
53 	gpiod_set_value(host->clk, 1);  in cbus_send_bit()
54 	gpiod_set_value(host->clk, 0);  in cbus_send_bit()
58  * cbus_send_data - sends @len amount of data over the bus
67 	for (i = len; i > 0; i--)  in cbus_send_data()
68 		cbus_send_bit(host, data & (1 << (i - 1)));  in cbus_send_data()
72  * cbus_receive_bit - receives one bit from the bus
79 	gpiod_set_value(host->clk, 1);  in cbus_receive_bit()
80 	ret = gpiod_get_value(host->dat);  in cbus_receive_bit()
81 	gpiod_set_value(host->clk, 0);  in cbus_receive_bit()
86  * cbus_receive_word - receives 16-bit word from the bus
94 	for (i = 16; i > 0; i--) {  in cbus_receive_word()
101 			ret |= 1 << (i - 1);  in cbus_receive_word()
107  * cbus_transfer - transfers data over the bus
121 	spin_lock_irqsave(&host->lock, flags);  in cbus_transfer()
123 	/* Reset state and start of transfer, SEL stays down during transfer */  in cbus_transfer()
124 	gpiod_set_value(host->sel, 0);  in cbus_transfer()
127 	gpiod_direction_output(host->dat, 1);  in cbus_transfer()
142 		ret = gpiod_direction_input(host->dat);  in cbus_transfer()
144 			dev_dbg(host->dev, "failed setting direction\n");  in cbus_transfer()
147 		gpiod_set_value(host->clk, 1);  in cbus_transfer()
151 			dev_dbg(host->dev, "failed receiving data\n");  in cbus_transfer()
156 	/* Indicate end of transfer, SEL goes up until next transfer */  in cbus_transfer()
157 	gpiod_set_value(host->sel, 1);  in cbus_transfer()
158 	gpiod_set_value(host->clk, 1);  in cbus_transfer()
159 	gpiod_set_value(host->clk, 0);  in cbus_transfer()
162 	spin_unlock_irqrestore(&host->lock, flags);  in cbus_transfer()
179 		return -EINVAL;  in cbus_i2c_smbus_xfer()
182 			    command, data->word);  in cbus_i2c_smbus_xfer()
187 		data->word = ret;  in cbus_i2c_smbus_xfer()
215 	adapter = devm_kzalloc(&pdev->dev, sizeof(struct i2c_adapter),  in cbus_i2c_probe()
218 		return -ENOMEM;  in cbus_i2c_probe()
220 	chost = devm_kzalloc(&pdev->dev, sizeof(*chost), GFP_KERNEL);  in cbus_i2c_probe()
222 		return -ENOMEM;  in cbus_i2c_probe()
224 	if (gpiod_count(&pdev->dev, NULL) != 3)  in cbus_i2c_probe()
225 		return -ENODEV;  in cbus_i2c_probe()
226 	chost->clk = devm_gpiod_get_index(&pdev->dev, NULL, 0, GPIOD_OUT_LOW);  in cbus_i2c_probe()
227 	if (IS_ERR(chost->clk))  in cbus_i2c_probe()
228 		return PTR_ERR(chost->clk);  in cbus_i2c_probe()
229 	chost->dat = devm_gpiod_get_index(&pdev->dev, NULL, 1, GPIOD_IN);  in cbus_i2c_probe()
230 	if (IS_ERR(chost->dat))  in cbus_i2c_probe()
231 		return PTR_ERR(chost->dat);  in cbus_i2c_probe()
232 	chost->sel = devm_gpiod_get_index(&pdev->dev, NULL, 2, GPIOD_OUT_HIGH);  in cbus_i2c_probe()
233 	if (IS_ERR(chost->sel))  in cbus_i2c_probe()
234 		return PTR_ERR(chost->sel);  in cbus_i2c_probe()
235 	gpiod_set_consumer_name(chost->clk, "CBUS clk");  in cbus_i2c_probe()
236 	gpiod_set_consumer_name(chost->dat, "CBUS dat");  in cbus_i2c_probe()
237 	gpiod_set_consumer_name(chost->sel, "CBUS sel");  in cbus_i2c_probe()
239 	adapter->owner		= THIS_MODULE;  in cbus_i2c_probe()
240 	adapter->class		= I2C_CLASS_HWMON;  in cbus_i2c_probe()
241 	adapter->dev.parent	= &pdev->dev;  in cbus_i2c_probe()
242 	adapter->dev.of_node	= pdev->dev.of_node;  in cbus_i2c_probe()
243 	adapter->nr		= pdev->id;  in cbus_i2c_probe()
244 	adapter->timeout	= HZ;  in cbus_i2c_probe()
245 	adapter->algo		= &cbus_i2c_algo;  in cbus_i2c_probe()
246 	strscpy(adapter->name, "CBUS I2C adapter", sizeof(adapter->name));  in cbus_i2c_probe()
248 	spin_lock_init(&chost->lock);  in cbus_i2c_probe()
249 	chost->dev = &pdev->dev;  in cbus_i2c_probe()
259 	{ .compatible = "i2c-cbus-gpio", },
269 		.name	= "i2c-cbus-gpio",
275 MODULE_ALIAS("platform:i2c-cbus-gpio");