1 // SPDX-License-Identifier: GPL-2.0-only
21 #include <linux/hwmon-sysfs.h>
66 	int gpios[3];  member
71  * sample all GPIO's as analog voltages, a round-robin sampling method is used.
74  * LOCKING: must hold data->update_lock
79 	struct i2c_client *client = data->client;  in ltc4245_update_gpios()
83 	/* no extra gpio support, we're basically done */  in ltc4245_update_gpios()
84 	if (!data->use_extra_gpios) {  in ltc4245_update_gpios()
85 		data->gpios[0] = data->vregs[LTC4245_GPIOADC - 0x10];  in ltc4245_update_gpios()
91 	 * readings as stale by setting them to -EAGAIN  in ltc4245_update_gpios()
93 	if (time_after(jiffies, data->last_updated + 5 * HZ)) {  in ltc4245_update_gpios()
94 		for (i = 0; i < ARRAY_SIZE(data->gpios); i++)  in ltc4245_update_gpios()
95 			data->gpios[i] = -EAGAIN;  in ltc4245_update_gpios()
101 	 * The datasheet calls these GPIO[1-3], but we'll calculate the zero  in ltc4245_update_gpios()
102 	 * based array index instead, and call them GPIO[0-2]. This is much  in ltc4245_update_gpios()
105 	gpio_curr = (data->cregs[LTC4245_GPIO] & 0xc0) >> 6;  in ltc4245_update_gpios()
107 		gpio_curr -= 1;  in ltc4245_update_gpios()
110 	data->gpios[gpio_curr] = data->vregs[LTC4245_GPIOADC - 0x10];  in ltc4245_update_gpios()
113 	gpio_next = (gpio_curr + 1) % ARRAY_SIZE(data->gpios);  in ltc4245_update_gpios()
119 	gpio_reg = (data->cregs[LTC4245_GPIO] & 0x3f) | ((gpio_next + 1) << 6);  in ltc4245_update_gpios()
125 	data->cregs[LTC4245_GPIO] = gpio_reg;  in ltc4245_update_gpios()
131 	struct i2c_client *client = data->client;  in ltc4245_update_device()
135 	mutex_lock(&data->update_lock);  in ltc4245_update_device()
137 	if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {  in ltc4245_update_device()
139 		/* Read control registers -- 0x00 to 0x07 */  in ltc4245_update_device()
140 		for (i = 0; i < ARRAY_SIZE(data->cregs); i++) {  in ltc4245_update_device()
143 				data->cregs[i] = 0;  in ltc4245_update_device()
145 				data->cregs[i] = val;  in ltc4245_update_device()
148 		/* Read voltage registers -- 0x10 to 0x1c */  in ltc4245_update_device()
149 		for (i = 0; i < ARRAY_SIZE(data->vregs); i++) {  in ltc4245_update_device()
152 				data->vregs[i] = 0;  in ltc4245_update_device()
154 				data->vregs[i] = val;  in ltc4245_update_device()
160 		data->last_updated = jiffies;  in ltc4245_update_device()
161 		data->valid = true;  in ltc4245_update_device()
164 	mutex_unlock(&data->update_lock);  in ltc4245_update_device()
173 	const u8 regval = data->vregs[reg - 0x10];  in ltc4245_get_voltage()
191 		voltage = regval * -55;  in ltc4245_get_voltage()
209 	const u8 regval = data->vregs[reg - 0x10];  in ltc4245_get_current()
214 	 * The strange looking conversions that follow are fixed-point  in ltc4245_get_current()
278 		*val = !!(data->cregs[LTC4245_FAULT1] & BIT(channel + 4));  in ltc4245_read_curr()
281 		return -EOPNOTSUPP;  in ltc4245_read_curr()
295 			int regval = data->gpios[channel - 8];  in ltc4245_read_in()
304 			*val = !!(data->cregs[LTC4245_FAULT1] & BIT(channel));  in ltc4245_read_in()
306 			*val = !!(data->cregs[LTC4245_FAULT2] &  in ltc4245_read_in()
307 				  BIT(channel - 4));  in ltc4245_read_in()
310 		return -EOPNOTSUPP;  in ltc4245_read_in()
328 		return -EOPNOTSUPP;  in ltc4245_read_power()
342 		return ltc4245_read_in(dev, attr, channel - 1, val);  in ltc4245_read()
344 		return -EOPNOTSUPP;  in ltc4245_read()
360 			if (channel > 9 && !data->use_extra_gpios)  in ltc4245_is_visible()
429 	struct ltc4245_platform_data *pdata = dev_get_platdata(&client->dev);  in ltc4245_use_extra_gpios()
430 	struct device_node *np = client->dev.of_node;  in ltc4245_use_extra_gpios()
434 		return pdata->use_extra_gpios;  in ltc4245_use_extra_gpios()
437 	if (of_property_read_bool(np, "ltc4245,use-extra-gpios"))  in ltc4245_use_extra_gpios()
445 	struct i2c_adapter *adapter = client->adapter;  in ltc4245_probe()
450 		return -ENODEV;  in ltc4245_probe()
452 	data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);  in ltc4245_probe()
454 		return -ENOMEM;  in ltc4245_probe()
456 	data->client = client;  in ltc4245_probe()
457 	mutex_init(&data->update_lock);  in ltc4245_probe()
458 	data->use_extra_gpios = ltc4245_use_extra_gpios(client);  in ltc4245_probe()
464 	hwmon_dev = devm_hwmon_device_register_with_info(&client->dev,  in ltc4245_probe()
465 							 client->name, data,  in ltc4245_probe()