1 // SPDX-License-Identifier: GPL-2.0-only
8  * 28 GPIOs. 8 of them can trigger an interrupt. See datasheet for more
11  * - DIN must be stable at the rising edge of clock.
12  * - when writing:
13  *   - always clock in 16 clocks at once
14  *   - at DIN: D15 first, D0 last
15  *   - D0..D7 = databyte, D8..D14 = commandbyte
16  *   - D15 = low -> write command
17  * - when reading
18  *   - always clock in 16 clocks at once
19  *   - at DIN: D15 first, D0 last
20  *   - D0..D7 = dummy, D8..D14 = register address
21  *   - D15 = high -> read command
22  *   - raise CS and assert it again
23  *   - always clock in 16 clocks at once
24  *   - at DOUT: D15 first, D0 last
25  *   - D0..D7 contains the data from the first cycle
59 	config = &ts->port_config[offset >> 2];  in max7301_direction_input()
61 	if (ts->input_pullup_active & BIT(offset))  in max7301_direction_input()
66 	mutex_lock(&ts->lock);  in max7301_direction_input()
71 	ret = ts->write(ts->dev, 0x08 + (offset >> 2), *config);  in max7301_direction_input()
73 	mutex_unlock(&ts->lock);  in max7301_direction_input()
81 		ts->out_level |= 1 << offset;  in __max7301_set()
82 		return ts->write(ts->dev, 0x20 + offset, 0x01);  in __max7301_set()
84 		ts->out_level &= ~(1 << offset);  in __max7301_set()
85 		return ts->write(ts->dev, 0x20 + offset, 0x00);  in __max7301_set()
101 	config = &ts->port_config[offset >> 2];  in max7301_direction_output()
103 	mutex_lock(&ts->lock);  in max7301_direction_output()
111 		ret = ts->write(ts->dev, 0x08 + (offset >> 2), *config);  in max7301_direction_output()
113 	mutex_unlock(&ts->lock);  in max7301_direction_output()
121 	int config, level = -EINVAL;  in max7301_get()
126 	mutex_lock(&ts->lock);  in max7301_get()
128 	config = (ts->port_config[offset >> 2] >> ((offset & 3) << 1))  in max7301_get()
134 		level =  !!(ts->out_level & (1 << offset));  in max7301_get()
139 		level = ts->read(ts->dev, 0x20 + offset) & 0x01;  in max7301_get()
141 	mutex_unlock(&ts->lock);  in max7301_get()
153 	mutex_lock(&ts->lock);  in max7301_set()
157 	mutex_unlock(&ts->lock);  in max7301_set()
162 	struct device *dev = ts->dev;  in __max730x_probe()
168 	mutex_init(&ts->lock);  in __max730x_probe()
172 	ts->write(dev, 0x04, 0x01);  in __max730x_probe()
175 		ts->input_pullup_active = pdata->input_pullup_active;  in __max730x_probe()
176 		ts->chip.base = pdata->base;  in __max730x_probe()
178 		ts->chip.base = -1;  in __max730x_probe()
180 	ts->chip.label = dev->driver->name;  in __max730x_probe()
182 	ts->chip.direction_input = max7301_direction_input;  in __max730x_probe()
183 	ts->chip.get = max7301_get;  in __max730x_probe()
184 	ts->chip.direction_output = max7301_direction_output;  in __max730x_probe()
185 	ts->chip.set = max7301_set;  in __max730x_probe()
187 	ts->chip.ngpio = PIN_NUMBER;  in __max730x_probe()
188 	ts->chip.can_sleep = true;  in __max730x_probe()
189 	ts->chip.parent = dev;  in __max730x_probe()
190 	ts->chip.owner = THIS_MODULE;  in __max730x_probe()
204 		ts->port_config[i] = 0xAA;  in __max730x_probe()
206 			int offset = (i - 1) * 4 + j;  in __max730x_probe()
207 			ret = max7301_direction_input(&ts->chip, offset);  in __max730x_probe()
213 	ret = gpiochip_add_data(&ts->chip, ts);  in __max730x_probe()
218 	mutex_destroy(&ts->lock);  in __max730x_probe()
228 	ts->write(dev, 0x04, 0x00);  in __max730x_remove()
229 	gpiochip_remove(&ts->chip);  in __max730x_remove()
230 	mutex_destroy(&ts->lock);  in __max730x_remove()
236 MODULE_DESCRIPTION("MAX730x GPIO-Expanders, generic parts");