1 // SPDX-License-Identifier: GPL-2.0
3 * MAX1600 PCMCIA power switch library
5 * Copyright (C) 2016 Russell King
7 #include <linux/device.h>
8 #include <linux/module.h>
9 #include <linux/gpio/consumer.h>
10 #include <linux/slab.h>
13 static const char *max1600_gpio_name[2][MAX1600_GPIO_MAX] = {
14 { "a0vcc", "a1vcc", "a0vpp", "a1vpp" },
15 { "b0vcc", "b1vcc", "b0vpp", "b1vpp" },
18 int max1600_init(struct device *dev, struct max1600 **ptr,
19 unsigned int channel, unsigned int code)
36 if (code != MAX1600_CODE_LOW && code != MAX1600_CODE_HIGH)
39 m = devm_kzalloc(dev, sizeof(*m), GFP_KERNEL);
46 for (i = 0; i < MAX1600_GPIO_MAX; i++) {
49 name = max1600_gpio_name[chan][i];
50 if (i != MAX1600_GPIO_0VPP) {
51 m->gpio[i] = devm_gpiod_get(dev, name, GPIOD_OUT_LOW);
53 m->gpio[i] = devm_gpiod_get_optional(dev, name,
58 if (IS_ERR(m->gpio[i]))
59 return PTR_ERR(m->gpio[i]);
66 EXPORT_SYMBOL_GPL(max1600_init);
68 int max1600_configure(struct max1600 *m, unsigned int vcc, unsigned int vpp)
70 DECLARE_BITMAP(values, MAX1600_GPIO_MAX) = { 0, };
71 int n = MAX1600_GPIO_0VPP;
73 if (m->gpio[MAX1600_GPIO_0VPP]) {
75 __assign_bit(MAX1600_GPIO_0VPP, values, 0);
76 __assign_bit(MAX1600_GPIO_1VPP, values, 0);
77 } else if (vpp == 120) {
78 __assign_bit(MAX1600_GPIO_0VPP, values, 0);
79 __assign_bit(MAX1600_GPIO_1VPP, values, 1);
80 } else if (vpp == vcc) {
81 __assign_bit(MAX1600_GPIO_0VPP, values, 1);
82 __assign_bit(MAX1600_GPIO_1VPP, values, 0);
84 dev_err(m->dev, "unrecognised Vpp %u.%uV\n",
89 } else if (vpp != vcc && vpp != 0) {
90 dev_err(m->dev, "no VPP control\n");
95 __assign_bit(MAX1600_GPIO_0VCC, values, 0);
96 __assign_bit(MAX1600_GPIO_1VCC, values, 0);
97 } else if (vcc == 33) { /* VY */
98 __assign_bit(MAX1600_GPIO_0VCC, values, 1);
99 __assign_bit(MAX1600_GPIO_1VCC, values, 0);
100 } else if (vcc == 50) { /* VX */
101 __assign_bit(MAX1600_GPIO_0VCC, values, 0);
102 __assign_bit(MAX1600_GPIO_1VCC, values, 1);
104 dev_err(m->dev, "unrecognised Vcc %u.%uV\n",
109 if (m->code == MAX1600_CODE_HIGH) {
111 * Cirrus mode appears to be the same as Intel mode,
112 * except the VCC pins are inverted.
114 __change_bit(MAX1600_GPIO_0VCC, values);
115 __change_bit(MAX1600_GPIO_1VCC, values);
118 return gpiod_set_array_value_cansleep(n, m->gpio, NULL, values);
120 EXPORT_SYMBOL_GPL(max1600_configure);
122 MODULE_LICENSE("GPL v2");