1 // SPDX-License-Identifier: GPL-2.0-only
3  * Linear Technology LTC4306 and LTC4305 I2C multiplexer/switch
7  * Based on: i2c-mux-pca954x.c
14 #include <linux/i2c-mux.h>
15 #include <linux/i2c.h>
81 	ret = regmap_read(data->regmap, LTC_REG_CONFIG, &val);  in ltc4306_gpio_get()
85 	return !!(val & BIT(1 - offset));  in ltc4306_gpio_get()
93 	return regmap_update_bits(data->regmap, LTC_REG_CONFIG,  in ltc4306_gpio_set()
94 				  BIT(5 - offset), value ? BIT(5 - offset) : 0);  in ltc4306_gpio_set()
104 	ret = regmap_read(data->regmap, LTC_REG_MODE, &val);  in ltc4306_gpio_get_direction()
108 	return !!(val & BIT(7 - offset));  in ltc4306_gpio_get_direction()
116 	return regmap_update_bits(data->regmap, LTC_REG_MODE,  in ltc4306_gpio_direction_input()
117 				  BIT(7 - offset), BIT(7 - offset));  in ltc4306_gpio_direction_input()
126 	return regmap_update_bits(data->regmap, LTC_REG_MODE,  in ltc4306_gpio_direction_output()
127 				  BIT(7 - offset), 0);  in ltc4306_gpio_direction_output()
141 		val = BIT(4 - offset);  in ltc4306_gpio_set_config()
144 		return -ENOTSUPP;  in ltc4306_gpio_set_config()
147 	return regmap_update_bits(data->regmap, LTC_REG_MODE,  in ltc4306_gpio_set_config()
148 				  BIT(4 - offset), val);  in ltc4306_gpio_set_config()
153 	struct device *dev = regmap_get_device(data->regmap);  in ltc4306_gpio_init()
155 	if (!data->chip->num_gpios)  in ltc4306_gpio_init()
158 	data->gpiochip.label = dev_name(dev);  in ltc4306_gpio_init()
159 	data->gpiochip.base = -1;  in ltc4306_gpio_init()
160 	data->gpiochip.ngpio = data->chip->num_gpios;  in ltc4306_gpio_init()
161 	data->gpiochip.parent = dev;  in ltc4306_gpio_init()
162 	data->gpiochip.can_sleep = true;  in ltc4306_gpio_init()
163 	data->gpiochip.get_direction = ltc4306_gpio_get_direction;  in ltc4306_gpio_init()
164 	data->gpiochip.direction_input = ltc4306_gpio_direction_input;  in ltc4306_gpio_init()
165 	data->gpiochip.direction_output = ltc4306_gpio_direction_output;  in ltc4306_gpio_init()
166 	data->gpiochip.get = ltc4306_gpio_get;  in ltc4306_gpio_init()
167 	data->gpiochip.set = ltc4306_gpio_set;  in ltc4306_gpio_init()
168 	data->gpiochip.set_config = ltc4306_gpio_set_config;  in ltc4306_gpio_init()
169 	data->gpiochip.owner = THIS_MODULE;  in ltc4306_gpio_init()
172 	regmap_write(data->regmap, LTC_REG_MODE, LTC_GPIO_ALL_INPUT);  in ltc4306_gpio_init()
174 	return devm_gpiochip_add_data(dev, &data->gpiochip, data);  in ltc4306_gpio_init()
181 	return regmap_update_bits(data->regmap, LTC_REG_SWITCH,  in ltc4306_select_mux()
182 				  LTC_SWITCH_MASK, BIT(7 - chan));  in ltc4306_select_mux()
189 	return regmap_update_bits(data->regmap, LTC_REG_SWITCH,  in ltc4306_deselect_mux()
198 MODULE_DEVICE_TABLE(i2c, ltc4306_id);
209 	struct i2c_adapter *adap = client->adapter;  in ltc4306_probe()
218 	chip = of_device_get_match_data(&client->dev);  in ltc4306_probe()
221 		chip = &chips[i2c_match_id(ltc4306_id, client)->driver_data];  in ltc4306_probe()
223 	idle_disc = device_property_read_bool(&client->dev,  in ltc4306_probe()
224 					      "i2c-mux-idle-disconnect");  in ltc4306_probe()
226 	muxc = i2c_mux_alloc(adap, &client->dev,  in ltc4306_probe()
227 			     chip->nchans, sizeof(*data),  in ltc4306_probe()
231 		return -ENOMEM;  in ltc4306_probe()
233 	data->chip = chip;  in ltc4306_probe()
237 	data->regmap = devm_regmap_init_i2c(client, &ltc4306_regmap_config);  in ltc4306_probe()
238 	if (IS_ERR(data->regmap)) {  in ltc4306_probe()
239 		ret = PTR_ERR(data->regmap);  in ltc4306_probe()
240 		dev_err(&client->dev, "Failed to allocate register map: %d\n",  in ltc4306_probe()
245 	/* Reset and enable the mux if an enable GPIO is specified. */  in ltc4306_probe()
246 	gpio = devm_gpiod_get_optional(&client->dev, "enable", GPIOD_OUT_LOW);  in ltc4306_probe()
256 	 * Write the mux register at addr to verify  in ltc4306_probe()
257 	 * that the mux is in fact present. This also  in ltc4306_probe()
258 	 * initializes the mux to disconnected state.  in ltc4306_probe()
260 	if (regmap_write(data->regmap, LTC_REG_SWITCH, 0) < 0) {  in ltc4306_probe()
261 		dev_warn(&client->dev, "probe failed\n");  in ltc4306_probe()
262 		return -ENODEV;  in ltc4306_probe()
265 	if (device_property_read_bool(&client->dev,  in ltc4306_probe()
266 				      "ltc,downstream-accelerators-enable"))  in ltc4306_probe()
269 	if (device_property_read_bool(&client->dev,  in ltc4306_probe()
270 				      "ltc,upstream-accelerators-enable"))  in ltc4306_probe()
273 	if (regmap_write(data->regmap, LTC_REG_CONFIG, val) < 0)  in ltc4306_probe()
274 		return -ENODEV;  in ltc4306_probe()
281 	for (num = 0; num < chip->nchans; num++) {  in ltc4306_probe()
289 	dev_info(&client->dev,  in ltc4306_probe()
290 		 "registered %d multiplexed busses for I2C switch %s\n",  in ltc4306_probe()
291 		 num, client->name);  in ltc4306_probe()
316 MODULE_DESCRIPTION("Linear Technology LTC4306, LTC4305 I2C mux/switch driver");