5  * This file is based on: drivers/i2c/soft-i2c.c,
6  * with added driver-model support and code cleanup.
29 	  * udelay - delay [us] between GPIO toggle operations,
32 	int udelay;
34 	struct gpio_desc gpios[PIN_COUNT];  member
37 static int i2c_gpio_sda_get(struct gpio_desc *sda)  in i2c_gpio_sda_get()
42 static void i2c_gpio_sda_set(struct gpio_desc *sda, int bit)  in i2c_gpio_sda_set()
50 static void i2c_gpio_scl_set(struct gpio_desc *scl, int bit)  in i2c_gpio_scl_set()
60 			       int delay, uchar bit)  in i2c_gpio_write_bit()
70 static int i2c_gpio_read_bit(struct gpio_desc *scl, struct gpio_desc *sda,  in i2c_gpio_read_bit()
71 			     int delay)  in i2c_gpio_read_bit()
73 	int value;  in i2c_gpio_read_bit()
85 /* START: High -> Low on SDA while SCL is High */
87 				int delay)  in i2c_gpio_send_start()
98 /* STOP: Low -> High on SDA while SCL is High */
100 			       int delay)  in i2c_gpio_send_stop()
114 			      int delay, int ack)  in i2c_gpio_send_ack()
127 				int delay)  in i2c_gpio_send_reset()
129 	int j;  in i2c_gpio_send_reset()
139 			      int delay)  in i2c_gpio_sda_high()
148 static int i2c_gpio_write_byte(struct gpio_desc *scl, struct gpio_desc *sda,  in i2c_gpio_write_byte()
149 			       int delay, uchar data)  in i2c_gpio_write_byte()
151 	int j;  in i2c_gpio_write_byte()
152 	int nack;  in i2c_gpio_write_byte()
173 				int delay, int ack)  in i2c_gpio_read_byte()
175 	int  data;  in i2c_gpio_read_byte()
176 	int  j;  in i2c_gpio_read_byte()
190 int i2c_send_slave_addr(struct gpio_desc *scl, struct gpio_desc *sda, int delay,  in i2c_send_slave_addr()
197 		return -EIO;  in i2c_send_slave_addr()
203 static int i2c_gpio_write_data(struct i2c_gpio_bus *bus, uchar chip,  in i2c_gpio_write_data()
204 			       uchar *buffer, int len,  in i2c_gpio_write_data()
207 	struct gpio_desc *scl = &bus->gpios[PIN_SCL];  in i2c_gpio_write_data()
208 	struct gpio_desc *sda = &bus->gpios[PIN_SDA];  in i2c_gpio_write_data()
209 	unsigned int delay = bus->udelay;  in i2c_gpio_write_data()
210 	int failures = 0;  in i2c_gpio_write_data()
216 		return -EIO;  in i2c_gpio_write_data()
219 	while (len-- > 0) {  in i2c_gpio_write_data()
231 		return -EIO;  in i2c_gpio_write_data()
237 static int i2c_gpio_read_data(struct i2c_gpio_bus *bus, uchar chip,  in i2c_gpio_read_data()
238 			      uchar *buffer, int len)  in i2c_gpio_read_data()
240 	struct gpio_desc *scl = &bus->gpios[PIN_SCL];  in i2c_gpio_read_data()
241 	struct gpio_desc *sda = &bus->gpios[PIN_SDA];  in i2c_gpio_read_data()
242 	unsigned int delay = bus->udelay;  in i2c_gpio_read_data()
246 	while (len-- > 0)  in i2c_gpio_read_data()
254 static int i2c_gpio_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs)  in i2c_gpio_xfer()
257 	int ret;  in i2c_gpio_xfer()
259 	for (; nmsgs > 0; nmsgs--, msg++) {  in i2c_gpio_xfer()
262 		if (msg->flags & I2C_M_RD) {  in i2c_gpio_xfer()
263 			ret = i2c_gpio_read_data(bus, msg->addr, msg->buf,  in i2c_gpio_xfer()
264 						 msg->len);  in i2c_gpio_xfer()
266 			ret = i2c_gpio_write_data(bus, msg->addr, msg->buf,  in i2c_gpio_xfer()
267 						  msg->len, next_is_read);  in i2c_gpio_xfer()
271 			return -EREMOTEIO;  in i2c_gpio_xfer()
277 static int i2c_gpio_probe(struct udevice *dev, uint chip, uint chip_flags)  in i2c_gpio_probe()
280 	struct gpio_desc *scl = &bus->gpios[PIN_SCL];  in i2c_gpio_probe()
281 	struct gpio_desc *sda = &bus->gpios[PIN_SDA];  in i2c_gpio_probe()
282 	unsigned int delay = bus->udelay;  in i2c_gpio_probe()
283 	int ret;  in i2c_gpio_probe()
290 	      __func__, dev->seq, dev->name, chip, chip_flags, ret);  in i2c_gpio_probe()
295 static int i2c_gpio_set_bus_speed(struct udevice *dev, unsigned int speed_hz)  in i2c_gpio_set_bus_speed()
298 	struct gpio_desc *scl = &bus->gpios[PIN_SCL];  in i2c_gpio_set_bus_speed()
299 	struct gpio_desc *sda = &bus->gpios[PIN_SDA];  in i2c_gpio_set_bus_speed()
301 	bus->udelay = 1000000 / (speed_hz << 2);  in i2c_gpio_set_bus_speed()
303 	i2c_gpio_send_reset(scl, sda, bus->udelay);  in i2c_gpio_set_bus_speed()
308 static int i2c_gpio_ofdata_to_platdata(struct udevice *dev)  in i2c_gpio_ofdata_to_platdata()
311 	const void *blob = gd->fdt_blob;  in i2c_gpio_ofdata_to_platdata()
312 	int node = dev_of_offset(dev);  in i2c_gpio_ofdata_to_platdata()
313 	int ret;  in i2c_gpio_ofdata_to_platdata()
315 	ret = gpio_request_list_by_name(dev, "gpios", bus->gpios,  in i2c_gpio_ofdata_to_platdata()
316 					ARRAY_SIZE(bus->gpios), 0);  in i2c_gpio_ofdata_to_platdata()
320 	bus->udelay = fdtdec_get_int(blob, node, "i2c-gpio,delay-us",  in i2c_gpio_ofdata_to_platdata()
325 	pr_err("Can't get %s gpios! Error: %d", dev->name, ret);  in i2c_gpio_ofdata_to_platdata()
336 	{ .compatible = "i2c-gpio" },
341 	.name	= "i2c-gpio",