123 lines
2.8 KiB
C
123 lines
2.8 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* MAX1600 PCMCIA power switch library
|
|
*
|
|
* Copyright (C) 2016 Russell King
|
|
*/
|
|
#include <linux/device.h>
|
|
#include <linux/module.h>
|
|
#include <linux/gpio/consumer.h>
|
|
#include <linux/slab.h>
|
|
#include "max1600.h"
|
|
|
|
static const char *max1600_gpio_name[2][MAX1600_GPIO_MAX] = {
|
|
{ "a0vcc", "a1vcc", "a0vpp", "a1vpp" },
|
|
{ "b0vcc", "b1vcc", "b0vpp", "b1vpp" },
|
|
};
|
|
|
|
int max1600_init(struct device *dev, struct max1600 **ptr,
|
|
unsigned int channel, unsigned int code)
|
|
{
|
|
struct max1600 *m;
|
|
int chan;
|
|
int i;
|
|
|
|
switch (channel) {
|
|
case MAX1600_CHAN_A:
|
|
chan = 0;
|
|
break;
|
|
case MAX1600_CHAN_B:
|
|
chan = 1;
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (code != MAX1600_CODE_LOW && code != MAX1600_CODE_HIGH)
|
|
return -EINVAL;
|
|
|
|
m = devm_kzalloc(dev, sizeof(*m), GFP_KERNEL);
|
|
if (!m)
|
|
return -ENOMEM;
|
|
|
|
m->dev = dev;
|
|
m->code = code;
|
|
|
|
for (i = 0; i < MAX1600_GPIO_MAX; i++) {
|
|
const char *name;
|
|
|
|
name = max1600_gpio_name[chan][i];
|
|
if (i != MAX1600_GPIO_0VPP) {
|
|
m->gpio[i] = devm_gpiod_get(dev, name, GPIOD_OUT_LOW);
|
|
} else {
|
|
m->gpio[i] = devm_gpiod_get_optional(dev, name,
|
|
GPIOD_OUT_LOW);
|
|
if (!m->gpio[i])
|
|
break;
|
|
}
|
|
if (IS_ERR(m->gpio[i]))
|
|
return PTR_ERR(m->gpio[i]);
|
|
}
|
|
|
|
*ptr = m;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(max1600_init);
|
|
|
|
int max1600_configure(struct max1600 *m, unsigned int vcc, unsigned int vpp)
|
|
{
|
|
DECLARE_BITMAP(values, MAX1600_GPIO_MAX) = { 0, };
|
|
int n = MAX1600_GPIO_0VPP;
|
|
|
|
if (m->gpio[MAX1600_GPIO_0VPP]) {
|
|
if (vpp == 0) {
|
|
__assign_bit(MAX1600_GPIO_0VPP, values, 0);
|
|
__assign_bit(MAX1600_GPIO_1VPP, values, 0);
|
|
} else if (vpp == 120) {
|
|
__assign_bit(MAX1600_GPIO_0VPP, values, 0);
|
|
__assign_bit(MAX1600_GPIO_1VPP, values, 1);
|
|
} else if (vpp == vcc) {
|
|
__assign_bit(MAX1600_GPIO_0VPP, values, 1);
|
|
__assign_bit(MAX1600_GPIO_1VPP, values, 0);
|
|
} else {
|
|
dev_err(m->dev, "unrecognised Vpp %u.%uV\n",
|
|
vpp / 10, vpp % 10);
|
|
return -EINVAL;
|
|
}
|
|
n = MAX1600_GPIO_MAX;
|
|
} else if (vpp != vcc && vpp != 0) {
|
|
dev_err(m->dev, "no VPP control\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (vcc == 0) {
|
|
__assign_bit(MAX1600_GPIO_0VCC, values, 0);
|
|
__assign_bit(MAX1600_GPIO_1VCC, values, 0);
|
|
} else if (vcc == 33) { /* VY */
|
|
__assign_bit(MAX1600_GPIO_0VCC, values, 1);
|
|
__assign_bit(MAX1600_GPIO_1VCC, values, 0);
|
|
} else if (vcc == 50) { /* VX */
|
|
__assign_bit(MAX1600_GPIO_0VCC, values, 0);
|
|
__assign_bit(MAX1600_GPIO_1VCC, values, 1);
|
|
} else {
|
|
dev_err(m->dev, "unrecognised Vcc %u.%uV\n",
|
|
vcc / 10, vcc % 10);
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (m->code == MAX1600_CODE_HIGH) {
|
|
/*
|
|
* Cirrus mode appears to be the same as Intel mode,
|
|
* except the VCC pins are inverted.
|
|
*/
|
|
__change_bit(MAX1600_GPIO_0VCC, values);
|
|
__change_bit(MAX1600_GPIO_1VCC, values);
|
|
}
|
|
|
|
return gpiod_set_array_value_cansleep(n, m->gpio, NULL, values);
|
|
}
|
|
EXPORT_SYMBOL_GPL(max1600_configure);
|
|
|
|
MODULE_LICENSE("GPL v2");
|