android_kernel_xiaomi_sm8350/drivers/misc/ad525x_dpot.c
Michael Hennerich 6c536e4ce8 ad525x_dpot: add support for SPI parts
Split the bus logic out into separate files so that we can handle I2C and
SPI busses independently.  The new SPI bus logic brings in support for a
lot more parts:

	AD5160, AD5161, AD5162, AD5165, AD5200, AD5201, AD5203,
	AD5204, AD5206, AD5207, AD5231, AD5232, AD5233, AD5235,
	AD5260, AD5262, AD5263, AD5290, AD5291, AD5292, AD5293,
	AD7376, AD8400, AD8402, AD8403, ADN2850

[randy.dunlap@oracle.com: fix ad525X_dpot build]
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-25 08:07:04 -07:00

512 lines
13 KiB
C

/*
* ad525x_dpot: Driver for the Analog Devices digital potentiometers
* Copyright (c) 2009-2010 Analog Devices, Inc.
* Author: Michael Hennerich <hennerich@blackfin.uclinux.org>
*
* DEVID #Wipers #Positions Resistor Options (kOhm)
* AD5258 1 64 1, 10, 50, 100
* AD5259 1 256 5, 10, 50, 100
* AD5251 2 64 1, 10, 50, 100
* AD5252 2 256 1, 10, 50, 100
* AD5255 3 512 25, 250
* AD5253 4 64 1, 10, 50, 100
* AD5254 4 256 1, 10, 50, 100
* AD5160 1 256 5, 10, 50, 100
* AD5161 1 256 5, 10, 50, 100
* AD5162 2 256 2.5, 10, 50, 100
* AD5165 1 256 100
* AD5200 1 256 10, 50
* AD5201 1 33 10, 50
* AD5203 4 64 10, 100
* AD5204 4 256 10, 50, 100
* AD5206 6 256 10, 50, 100
* AD5207 2 256 10, 50, 100
* AD5231 1 1024 10, 50, 100
* AD5232 2 256 10, 50, 100
* AD5233 4 64 10, 50, 100
* AD5235 2 1024 25, 250
* AD5260 1 256 20, 50, 200
* AD5262 2 256 20, 50, 200
* AD5263 4 256 20, 50, 200
* AD5290 1 256 10, 50, 100
* AD5291 1 256 20
* AD5292 1 1024 20
* AD5293 1 1024 20
* AD7376 1 128 10, 50, 100, 1M
* AD8400 1 256 1, 10, 50, 100
* AD8402 2 256 1, 10, 50, 100
* AD8403 4 256 1, 10, 50, 100
* ADN2850 3 512 25, 250
*
* See Documentation/misc-devices/ad525x_dpot.txt for more info.
*
* derived from ad5258.c
* Copyright (c) 2009 Cyber Switching, Inc.
* Author: Chris Verges <chrisv@cyberswitching.com>
*
* derived from ad5252.c
* Copyright (c) 2006 Michael Hennerich <hennerich@blackfin.uclinux.org>
*
* Licensed under the GPL-2 or later.
*/
#include <linux/module.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/slab.h>
#define DRIVER_VERSION "0.2"
#include "ad525x_dpot.h"
/*
* Client data (each client gets its own)
*/
struct dpot_data {
struct ad_dpot_bus_data bdata;
struct mutex update_lock;
unsigned rdac_mask;
unsigned max_pos;
unsigned long devid;
unsigned uid;
unsigned feat;
unsigned wipers;
u16 rdac_cache[8];
};
static inline int dpot_read_d8(struct dpot_data *dpot)
{
return dpot->bdata.bops->read_d8(dpot->bdata.client);
}
static inline int dpot_read_r8d8(struct dpot_data *dpot, u8 reg)
{
return dpot->bdata.bops->read_r8d8(dpot->bdata.client, reg);
}
static inline int dpot_read_r8d16(struct dpot_data *dpot, u8 reg)
{
return dpot->bdata.bops->read_r8d16(dpot->bdata.client, reg);
}
static inline int dpot_write_d8(struct dpot_data *dpot, u8 val)
{
return dpot->bdata.bops->write_d8(dpot->bdata.client, val);
}
static inline int dpot_write_r8d8(struct dpot_data *dpot, u8 reg, u16 val)
{
return dpot->bdata.bops->write_r8d8(dpot->bdata.client, reg, val);
}
static inline int dpot_write_r8d16(struct dpot_data *dpot, u8 reg, u16 val)
{
return dpot->bdata.bops->write_r8d16(dpot->bdata.client, reg, val);
}
static s32 dpot_read(struct dpot_data *dpot, u8 reg)
{
unsigned val = 0;
if (dpot->feat & F_SPI) {
if (!(reg & (DPOT_ADDR_EEPROM | DPOT_ADDR_CMD))) {
if (dpot->feat & F_RDACS_WONLY)
return dpot->rdac_cache[reg & DPOT_RDAC_MASK];
if (dpot->uid == DPOT_UID(AD5291_ID) ||
dpot->uid == DPOT_UID(AD5292_ID) ||
dpot->uid == DPOT_UID(AD5293_ID))
return dpot_read_r8d8(dpot,
DPOT_AD5291_READ_RDAC << 2);
val = DPOT_SPI_READ_RDAC;
} else if (reg & DPOT_ADDR_EEPROM) {
val = DPOT_SPI_READ_EEPROM;
}
if (dpot->feat & F_SPI_16BIT)
return dpot_read_r8d8(dpot, val);
else if (dpot->feat & F_SPI_24BIT)
return dpot_read_r8d16(dpot, val);
} else { /* I2C */
if ((reg & DPOT_REG_TOL) || (dpot->max_pos > 256))
return dpot_read_r8d16(dpot, (reg & 0xF8) |
((reg & 0x7) << 1));
else
return dpot_read_r8d8(dpot, reg);
}
return -EFAULT;
}
static s32 dpot_write(struct dpot_data *dpot, u8 reg, u16 value)
{
unsigned val = 0;
if (dpot->feat & F_SPI) {
if (!(reg & (DPOT_ADDR_EEPROM | DPOT_ADDR_CMD))) {
if (dpot->feat & F_RDACS_WONLY)
dpot->rdac_cache[reg & DPOT_RDAC_MASK] = value;
if (dpot->feat & F_AD_APPDATA) {
if (dpot->feat & F_SPI_8BIT) {
val = ((reg & DPOT_RDAC_MASK) <<
DPOT_MAX_POS(dpot->devid)) |
value;
return dpot_write_d8(dpot, val);
} else if (dpot->feat & F_SPI_16BIT) {
val = ((reg & DPOT_RDAC_MASK) <<
DPOT_MAX_POS(dpot->devid)) |
value;
return dpot_write_r8d8(dpot, val >> 8,
val & 0xFF);
} else
BUG();
} else {
if (dpot->uid == DPOT_UID(AD5291_ID) ||
dpot->uid == DPOT_UID(AD5292_ID) ||
dpot->uid == DPOT_UID(AD5293_ID))
return dpot_write_r8d8(dpot,
(DPOT_AD5291_RDAC << 2) |
(value >> 8), value & 0xFF);
val = DPOT_SPI_RDAC | (reg & DPOT_RDAC_MASK);
}
} else if (reg & DPOT_ADDR_EEPROM) {
val = DPOT_SPI_EEPROM | (reg & DPOT_RDAC_MASK);
} else if (reg & DPOT_ADDR_CMD) {
switch (reg) {
case DPOT_DEC_ALL_6DB:
val = DPOT_SPI_DEC_ALL_6DB;
break;
case DPOT_INC_ALL_6DB:
val = DPOT_SPI_INC_ALL_6DB;
break;
case DPOT_DEC_ALL:
val = DPOT_SPI_DEC_ALL;
break;
case DPOT_INC_ALL:
val = DPOT_SPI_INC_ALL;
break;
}
} else
BUG();
if (dpot->feat & F_SPI_16BIT)
return dpot_write_r8d8(dpot, val, value);
else if (dpot->feat & F_SPI_24BIT)
return dpot_write_r8d16(dpot, val, value);
} else {
/* Only write the instruction byte for certain commands */
if (reg & DPOT_ADDR_CMD)
return dpot_write_d8(dpot, reg);
if (dpot->max_pos > 256)
return dpot_write_r8d16(dpot, (reg & 0xF8) |
((reg & 0x7) << 1), value);
else
/* All other registers require instruction + data bytes */
return dpot_write_r8d8(dpot, reg, value);
}
return -EFAULT;
}
/* sysfs functions */
static ssize_t sysfs_show_reg(struct device *dev,
struct device_attribute *attr,
char *buf, u32 reg)
{
struct dpot_data *data = dev_get_drvdata(dev);
s32 value;
mutex_lock(&data->update_lock);
value = dpot_read(data, reg);
mutex_unlock(&data->update_lock);
if (value < 0)
return -EINVAL;
/*
* Let someone else deal with converting this ...
* the tolerance is a two-byte value where the MSB
* is a sign + integer value, and the LSB is a
* decimal value. See page 18 of the AD5258
* datasheet (Rev. A) for more details.
*/
if (reg & DPOT_REG_TOL)
return sprintf(buf, "0x%04x\n", value & 0xFFFF);
else
return sprintf(buf, "%u\n", value & data->rdac_mask);
}
static ssize_t sysfs_set_reg(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count, u32 reg)
{
struct dpot_data *data = dev_get_drvdata(dev);
unsigned long value;
int err;
err = strict_strtoul(buf, 10, &value);
if (err)
return err;
if (value > data->rdac_mask)
value = data->rdac_mask;
mutex_lock(&data->update_lock);
dpot_write(data, reg, value);
if (reg & DPOT_ADDR_EEPROM)
msleep(26); /* Sleep while the EEPROM updates */
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t sysfs_do_cmd(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count, u32 reg)
{
struct dpot_data *data = dev_get_drvdata(dev);
mutex_lock(&data->update_lock);
dpot_write(data, reg, 0);
mutex_unlock(&data->update_lock);
return count;
}
/* ------------------------------------------------------------------------- */
#define DPOT_DEVICE_SHOW(_name, _reg) static ssize_t \
show_##_name(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
return sysfs_show_reg(dev, attr, buf, _reg); \
}
#define DPOT_DEVICE_SET(_name, _reg) static ssize_t \
set_##_name(struct device *dev, \
struct device_attribute *attr, \
const char *buf, size_t count) \
{ \
return sysfs_set_reg(dev, attr, buf, count, _reg); \
}
#define DPOT_DEVICE_SHOW_SET(name, reg) \
DPOT_DEVICE_SHOW(name, reg) \
DPOT_DEVICE_SET(name, reg) \
static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, show_##name, set_##name);
#define DPOT_DEVICE_SHOW_ONLY(name, reg) \
DPOT_DEVICE_SHOW(name, reg) \
static DEVICE_ATTR(name, S_IWUSR | S_IRUGO, show_##name, NULL);
DPOT_DEVICE_SHOW_SET(rdac0, DPOT_ADDR_RDAC | DPOT_RDAC0);
DPOT_DEVICE_SHOW_SET(eeprom0, DPOT_ADDR_EEPROM | DPOT_RDAC0);
DPOT_DEVICE_SHOW_ONLY(tolerance0, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC0);
DPOT_DEVICE_SHOW_SET(rdac1, DPOT_ADDR_RDAC | DPOT_RDAC1);
DPOT_DEVICE_SHOW_SET(eeprom1, DPOT_ADDR_EEPROM | DPOT_RDAC1);
DPOT_DEVICE_SHOW_ONLY(tolerance1, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC1);
DPOT_DEVICE_SHOW_SET(rdac2, DPOT_ADDR_RDAC | DPOT_RDAC2);
DPOT_DEVICE_SHOW_SET(eeprom2, DPOT_ADDR_EEPROM | DPOT_RDAC2);
DPOT_DEVICE_SHOW_ONLY(tolerance2, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC2);
DPOT_DEVICE_SHOW_SET(rdac3, DPOT_ADDR_RDAC | DPOT_RDAC3);
DPOT_DEVICE_SHOW_SET(eeprom3, DPOT_ADDR_EEPROM | DPOT_RDAC3);
DPOT_DEVICE_SHOW_ONLY(tolerance3, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC3);
DPOT_DEVICE_SHOW_SET(rdac4, DPOT_ADDR_RDAC | DPOT_RDAC4);
DPOT_DEVICE_SHOW_SET(eeprom4, DPOT_ADDR_EEPROM | DPOT_RDAC4);
DPOT_DEVICE_SHOW_ONLY(tolerance4, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC4);
DPOT_DEVICE_SHOW_SET(rdac5, DPOT_ADDR_RDAC | DPOT_RDAC5);
DPOT_DEVICE_SHOW_SET(eeprom5, DPOT_ADDR_EEPROM | DPOT_RDAC5);
DPOT_DEVICE_SHOW_ONLY(tolerance5, DPOT_ADDR_EEPROM | DPOT_TOL_RDAC5);
static const struct attribute *dpot_attrib_wipers[] = {
&dev_attr_rdac0.attr,
&dev_attr_rdac1.attr,
&dev_attr_rdac2.attr,
&dev_attr_rdac3.attr,
&dev_attr_rdac4.attr,
&dev_attr_rdac5.attr,
NULL
};
static const struct attribute *dpot_attrib_eeprom[] = {
&dev_attr_eeprom0.attr,
&dev_attr_eeprom1.attr,
&dev_attr_eeprom2.attr,
&dev_attr_eeprom3.attr,
&dev_attr_eeprom4.attr,
&dev_attr_eeprom5.attr,
NULL
};
static const struct attribute *dpot_attrib_tolerance[] = {
&dev_attr_tolerance0.attr,
&dev_attr_tolerance1.attr,
&dev_attr_tolerance2.attr,
&dev_attr_tolerance3.attr,
&dev_attr_tolerance4.attr,
&dev_attr_tolerance5.attr,
NULL
};
/* ------------------------------------------------------------------------- */
#define DPOT_DEVICE_DO_CMD(_name, _cmd) static ssize_t \
set_##_name(struct device *dev, \
struct device_attribute *attr, \
const char *buf, size_t count) \
{ \
return sysfs_do_cmd(dev, attr, buf, count, _cmd); \
} \
static DEVICE_ATTR(_name, S_IWUSR | S_IRUGO, NULL, set_##_name);
DPOT_DEVICE_DO_CMD(inc_all, DPOT_INC_ALL);
DPOT_DEVICE_DO_CMD(dec_all, DPOT_DEC_ALL);
DPOT_DEVICE_DO_CMD(inc_all_6db, DPOT_INC_ALL_6DB);
DPOT_DEVICE_DO_CMD(dec_all_6db, DPOT_DEC_ALL_6DB);
static struct attribute *ad525x_attributes_commands[] = {
&dev_attr_inc_all.attr,
&dev_attr_dec_all.attr,
&dev_attr_inc_all_6db.attr,
&dev_attr_dec_all_6db.attr,
NULL
};
static const struct attribute_group ad525x_group_commands = {
.attrs = ad525x_attributes_commands,
};
__devinit int ad_dpot_add_files(struct device *dev,
unsigned features, unsigned rdac)
{
int err = sysfs_create_file(&dev->kobj,
dpot_attrib_wipers[rdac]);
if (features & F_CMD_EEP)
err |= sysfs_create_file(&dev->kobj,
dpot_attrib_eeprom[rdac]);
if (features & F_CMD_TOL)
err |= sysfs_create_file(&dev->kobj,
dpot_attrib_tolerance[rdac]);
if (err)
dev_err(dev, "failed to register sysfs hooks for RDAC%d\n",
rdac);
return err;
}
inline void ad_dpot_remove_files(struct device *dev,
unsigned features, unsigned rdac)
{
sysfs_remove_file(&dev->kobj,
dpot_attrib_wipers[rdac]);
if (features & F_CMD_EEP)
sysfs_remove_file(&dev->kobj,
dpot_attrib_eeprom[rdac]);
if (features & F_CMD_TOL)
sysfs_remove_file(&dev->kobj,
dpot_attrib_tolerance[rdac]);
}
__devinit int ad_dpot_probe(struct device *dev,
struct ad_dpot_bus_data *bdata, const struct ad_dpot_id *id)
{
struct dpot_data *data;
int i, err = 0;
data = kzalloc(sizeof(struct dpot_data), GFP_KERNEL);
if (!data) {
err = -ENOMEM;
goto exit;
}
dev_set_drvdata(dev, data);
mutex_init(&data->update_lock);
data->bdata = *bdata;
data->devid = id->devid;
data->max_pos = 1 << DPOT_MAX_POS(data->devid);
data->rdac_mask = data->max_pos - 1;
data->feat = DPOT_FEAT(data->devid);
data->uid = DPOT_UID(data->devid);
data->wipers = DPOT_WIPERS(data->devid);
for (i = DPOT_RDAC0; i <= DPOT_RDAC5; i++)
if (data->wipers & (1 << i)) {
err = ad_dpot_add_files(dev, data->feat, i);
if (err)
goto exit_remove_files;
/* power-up midscale */
if (data->feat & F_RDACS_WONLY)
data->rdac_cache[i] = data->max_pos / 2;
}
if (data->feat & F_CMD_INC)
err = sysfs_create_group(&dev->kobj, &ad525x_group_commands);
if (err) {
dev_err(dev, "failed to register sysfs hooks\n");
goto exit_free;
}
dev_info(dev, "%s %d-Position Digital Potentiometer registered\n",
id->name, data->max_pos);
return 0;
exit_remove_files:
for (i = DPOT_RDAC0; i <= DPOT_RDAC5; i++)
if (data->wipers & (1 << i))
ad_dpot_remove_files(dev, data->feat, i);
exit_free:
kfree(data);
dev_set_drvdata(dev, NULL);
exit:
dev_err(dev, "failed to create client for %s ID 0x%lX\n",
id->name, id->devid);
return err;
}
EXPORT_SYMBOL(ad_dpot_probe);
__devexit int ad_dpot_remove(struct device *dev)
{
struct dpot_data *data = dev_get_drvdata(dev);
int i;
for (i = DPOT_RDAC0; i <= DPOT_RDAC5; i++)
if (data->wipers & (1 << i))
ad_dpot_remove_files(dev, data->feat, i);
kfree(data);
return 0;
}
EXPORT_SYMBOL(ad_dpot_remove);
MODULE_AUTHOR("Chris Verges <chrisv@cyberswitching.com>, "
"Michael Hennerich <hennerich@blackfin.uclinux.org>");
MODULE_DESCRIPTION("Digital potentiometer driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRIVER_VERSION);