alistair23-linux/drivers/mfd/aat2870-core.c
Greg Kroah-Hartman dc607f6bba mfd: aat2870: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20190706164722.18766-3-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-08-01 08:06:59 +02:00

466 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* linux/drivers/mfd/aat2870-core.c
*
* Copyright (c) 2011, NVIDIA Corporation.
* Author: Jin Park <jinyoungp@nvidia.com>
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/mfd/core.h>
#include <linux/mfd/aat2870.h>
#include <linux/regulator/machine.h>
static struct aat2870_register aat2870_regs[AAT2870_REG_NUM] = {
/* readable, writeable, value */
{ 0, 1, 0x00 }, /* 0x00 AAT2870_BL_CH_EN */
{ 0, 1, 0x16 }, /* 0x01 AAT2870_BLM */
{ 0, 1, 0x16 }, /* 0x02 AAT2870_BLS */
{ 0, 1, 0x56 }, /* 0x03 AAT2870_BL1 */
{ 0, 1, 0x56 }, /* 0x04 AAT2870_BL2 */
{ 0, 1, 0x56 }, /* 0x05 AAT2870_BL3 */
{ 0, 1, 0x56 }, /* 0x06 AAT2870_BL4 */
{ 0, 1, 0x56 }, /* 0x07 AAT2870_BL5 */
{ 0, 1, 0x56 }, /* 0x08 AAT2870_BL6 */
{ 0, 1, 0x56 }, /* 0x09 AAT2870_BL7 */
{ 0, 1, 0x56 }, /* 0x0A AAT2870_BL8 */
{ 0, 1, 0x00 }, /* 0x0B AAT2870_FLR */
{ 0, 1, 0x03 }, /* 0x0C AAT2870_FM */
{ 0, 1, 0x03 }, /* 0x0D AAT2870_FS */
{ 0, 1, 0x10 }, /* 0x0E AAT2870_ALS_CFG0 */
{ 0, 1, 0x06 }, /* 0x0F AAT2870_ALS_CFG1 */
{ 0, 1, 0x00 }, /* 0x10 AAT2870_ALS_CFG2 */
{ 1, 0, 0x00 }, /* 0x11 AAT2870_AMB */
{ 0, 1, 0x00 }, /* 0x12 AAT2870_ALS0 */
{ 0, 1, 0x00 }, /* 0x13 AAT2870_ALS1 */
{ 0, 1, 0x00 }, /* 0x14 AAT2870_ALS2 */
{ 0, 1, 0x00 }, /* 0x15 AAT2870_ALS3 */
{ 0, 1, 0x00 }, /* 0x16 AAT2870_ALS4 */
{ 0, 1, 0x00 }, /* 0x17 AAT2870_ALS5 */
{ 0, 1, 0x00 }, /* 0x18 AAT2870_ALS6 */
{ 0, 1, 0x00 }, /* 0x19 AAT2870_ALS7 */
{ 0, 1, 0x00 }, /* 0x1A AAT2870_ALS8 */
{ 0, 1, 0x00 }, /* 0x1B AAT2870_ALS9 */
{ 0, 1, 0x00 }, /* 0x1C AAT2870_ALSA */
{ 0, 1, 0x00 }, /* 0x1D AAT2870_ALSB */
{ 0, 1, 0x00 }, /* 0x1E AAT2870_ALSC */
{ 0, 1, 0x00 }, /* 0x1F AAT2870_ALSD */
{ 0, 1, 0x00 }, /* 0x20 AAT2870_ALSE */
{ 0, 1, 0x00 }, /* 0x21 AAT2870_ALSF */
{ 0, 1, 0x00 }, /* 0x22 AAT2870_SUB_SET */
{ 0, 1, 0x00 }, /* 0x23 AAT2870_SUB_CTRL */
{ 0, 1, 0x00 }, /* 0x24 AAT2870_LDO_AB */
{ 0, 1, 0x00 }, /* 0x25 AAT2870_LDO_CD */
{ 0, 1, 0x00 }, /* 0x26 AAT2870_LDO_EN */
};
static struct mfd_cell aat2870_devs[] = {
{
.name = "aat2870-backlight",
.id = AAT2870_ID_BL,
.pdata_size = sizeof(struct aat2870_bl_platform_data),
},
{
.name = "aat2870-regulator",
.id = AAT2870_ID_LDOA,
.pdata_size = sizeof(struct regulator_init_data),
},
{
.name = "aat2870-regulator",
.id = AAT2870_ID_LDOB,
.pdata_size = sizeof(struct regulator_init_data),
},
{
.name = "aat2870-regulator",
.id = AAT2870_ID_LDOC,
.pdata_size = sizeof(struct regulator_init_data),
},
{
.name = "aat2870-regulator",
.id = AAT2870_ID_LDOD,
.pdata_size = sizeof(struct regulator_init_data),
},
};
static int __aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
{
int ret;
if (addr >= AAT2870_REG_NUM) {
dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
return -EINVAL;
}
if (!aat2870->reg_cache[addr].readable) {
*val = aat2870->reg_cache[addr].value;
goto out;
}
ret = i2c_master_send(aat2870->client, &addr, 1);
if (ret < 0)
return ret;
if (ret != 1)
return -EIO;
ret = i2c_master_recv(aat2870->client, val, 1);
if (ret < 0)
return ret;
if (ret != 1)
return -EIO;
out:
dev_dbg(aat2870->dev, "read: addr=0x%02x, val=0x%02x\n", addr, *val);
return 0;
}
static int __aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
{
u8 msg[2];
int ret;
if (addr >= AAT2870_REG_NUM) {
dev_err(aat2870->dev, "Invalid address, 0x%02x\n", addr);
return -EINVAL;
}
if (!aat2870->reg_cache[addr].writeable) {
dev_err(aat2870->dev, "Address 0x%02x is not writeable\n",
addr);
return -EINVAL;
}
msg[0] = addr;
msg[1] = val;
ret = i2c_master_send(aat2870->client, msg, 2);
if (ret < 0)
return ret;
if (ret != 2)
return -EIO;
aat2870->reg_cache[addr].value = val;
dev_dbg(aat2870->dev, "write: addr=0x%02x, val=0x%02x\n", addr, val);
return 0;
}
static int aat2870_read(struct aat2870_data *aat2870, u8 addr, u8 *val)
{
int ret;
mutex_lock(&aat2870->io_lock);
ret = __aat2870_read(aat2870, addr, val);
mutex_unlock(&aat2870->io_lock);
return ret;
}
static int aat2870_write(struct aat2870_data *aat2870, u8 addr, u8 val)
{
int ret;
mutex_lock(&aat2870->io_lock);
ret = __aat2870_write(aat2870, addr, val);
mutex_unlock(&aat2870->io_lock);
return ret;
}
static int aat2870_update(struct aat2870_data *aat2870, u8 addr, u8 mask,
u8 val)
{
int change;
u8 old_val, new_val;
int ret;
mutex_lock(&aat2870->io_lock);
ret = __aat2870_read(aat2870, addr, &old_val);
if (ret)
goto out_unlock;
new_val = (old_val & ~mask) | (val & mask);
change = old_val != new_val;
if (change)
ret = __aat2870_write(aat2870, addr, new_val);
out_unlock:
mutex_unlock(&aat2870->io_lock);
return ret;
}
static inline void aat2870_enable(struct aat2870_data *aat2870)
{
if (aat2870->en_pin >= 0)
gpio_set_value(aat2870->en_pin, 1);
aat2870->is_enable = 1;
}
static inline void aat2870_disable(struct aat2870_data *aat2870)
{
if (aat2870->en_pin >= 0)
gpio_set_value(aat2870->en_pin, 0);
aat2870->is_enable = 0;
}
#ifdef CONFIG_DEBUG_FS
static ssize_t aat2870_dump_reg(struct aat2870_data *aat2870, char *buf)
{
u8 addr, val;
ssize_t count = 0;
int ret;
count += sprintf(buf, "aat2870 registers\n");
for (addr = 0; addr < AAT2870_REG_NUM; addr++) {
count += sprintf(buf + count, "0x%02x: ", addr);
if (count >= PAGE_SIZE - 1)
break;
ret = aat2870->read(aat2870, addr, &val);
if (ret == 0)
count += snprintf(buf + count, PAGE_SIZE - count,
"0x%02x", val);
else
count += snprintf(buf + count, PAGE_SIZE - count,
"<read fail: %d>", ret);
if (count >= PAGE_SIZE - 1)
break;
count += snprintf(buf + count, PAGE_SIZE - count, "\n");
if (count >= PAGE_SIZE - 1)
break;
}
/* Truncate count; min() would cause a warning */
if (count >= PAGE_SIZE)
count = PAGE_SIZE - 1;
return count;
}
static ssize_t aat2870_reg_read_file(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
struct aat2870_data *aat2870 = file->private_data;
char *buf;
ssize_t ret;
buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
if (!buf)
return -ENOMEM;
ret = aat2870_dump_reg(aat2870, buf);
if (ret >= 0)
ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
kfree(buf);
return ret;
}
static ssize_t aat2870_reg_write_file(struct file *file,
const char __user *user_buf, size_t count,
loff_t *ppos)
{
struct aat2870_data *aat2870 = file->private_data;
char buf[32];
ssize_t buf_size;
char *start = buf;
unsigned long addr, val;
int ret;
buf_size = min(count, (size_t)(sizeof(buf)-1));
if (copy_from_user(buf, user_buf, buf_size)) {
dev_err(aat2870->dev, "Failed to copy from user\n");
return -EFAULT;
}
buf[buf_size] = 0;
while (*start == ' ')
start++;
ret = kstrtoul(start, 16, &addr);
if (ret)
return ret;
if (addr >= AAT2870_REG_NUM) {
dev_err(aat2870->dev, "Invalid address, 0x%lx\n", addr);
return -EINVAL;
}
while (*start == ' ')
start++;
ret = kstrtoul(start, 16, &val);
if (ret)
return ret;
ret = aat2870->write(aat2870, (u8)addr, (u8)val);
if (ret)
return ret;
return buf_size;
}
static const struct file_operations aat2870_reg_fops = {
.open = simple_open,
.read = aat2870_reg_read_file,
.write = aat2870_reg_write_file,
};
static void aat2870_init_debugfs(struct aat2870_data *aat2870)
{
aat2870->dentry_root = debugfs_create_dir("aat2870", NULL);
debugfs_create_file("regs", 0644, aat2870->dentry_root, aat2870,
&aat2870_reg_fops);
}
#else
static inline void aat2870_init_debugfs(struct aat2870_data *aat2870)
{
}
#endif /* CONFIG_DEBUG_FS */
static int aat2870_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct aat2870_platform_data *pdata = dev_get_platdata(&client->dev);
struct aat2870_data *aat2870;
int i, j;
int ret = 0;
aat2870 = devm_kzalloc(&client->dev, sizeof(struct aat2870_data),
GFP_KERNEL);
if (!aat2870)
return -ENOMEM;
aat2870->dev = &client->dev;
dev_set_drvdata(aat2870->dev, aat2870);
aat2870->client = client;
i2c_set_clientdata(client, aat2870);
aat2870->reg_cache = aat2870_regs;
if (pdata->en_pin < 0)
aat2870->en_pin = -1;
else
aat2870->en_pin = pdata->en_pin;
aat2870->init = pdata->init;
aat2870->uninit = pdata->uninit;
aat2870->read = aat2870_read;
aat2870->write = aat2870_write;
aat2870->update = aat2870_update;
mutex_init(&aat2870->io_lock);
if (aat2870->init)
aat2870->init(aat2870);
if (aat2870->en_pin >= 0) {
ret = devm_gpio_request_one(&client->dev, aat2870->en_pin,
GPIOF_OUT_INIT_HIGH, "aat2870-en");
if (ret < 0) {
dev_err(&client->dev,
"Failed to request GPIO %d\n", aat2870->en_pin);
return ret;
}
}
aat2870_enable(aat2870);
for (i = 0; i < pdata->num_subdevs; i++) {
for (j = 0; j < ARRAY_SIZE(aat2870_devs); j++) {
if ((pdata->subdevs[i].id == aat2870_devs[j].id) &&
!strcmp(pdata->subdevs[i].name,
aat2870_devs[j].name)) {
aat2870_devs[j].platform_data =
pdata->subdevs[i].platform_data;
break;
}
}
}
ret = mfd_add_devices(aat2870->dev, 0, aat2870_devs,
ARRAY_SIZE(aat2870_devs), NULL, 0, NULL);
if (ret != 0) {
dev_err(aat2870->dev, "Failed to add subdev: %d\n", ret);
goto out_disable;
}
aat2870_init_debugfs(aat2870);
return 0;
out_disable:
aat2870_disable(aat2870);
return ret;
}
#ifdef CONFIG_PM_SLEEP
static int aat2870_i2c_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct aat2870_data *aat2870 = i2c_get_clientdata(client);
aat2870_disable(aat2870);
return 0;
}
static int aat2870_i2c_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct aat2870_data *aat2870 = i2c_get_clientdata(client);
struct aat2870_register *reg = NULL;
int i;
aat2870_enable(aat2870);
/* restore registers */
for (i = 0; i < AAT2870_REG_NUM; i++) {
reg = &aat2870->reg_cache[i];
if (reg->writeable)
aat2870->write(aat2870, i, reg->value);
}
return 0;
}
#endif /* CONFIG_PM_SLEEP */
static SIMPLE_DEV_PM_OPS(aat2870_pm_ops, aat2870_i2c_suspend,
aat2870_i2c_resume);
static const struct i2c_device_id aat2870_i2c_id_table[] = {
{ "aat2870", 0 },
{ }
};
static struct i2c_driver aat2870_i2c_driver = {
.driver = {
.name = "aat2870",
.pm = &aat2870_pm_ops,
.suppress_bind_attrs = true,
},
.probe = aat2870_i2c_probe,
.id_table = aat2870_i2c_id_table,
};
static int __init aat2870_init(void)
{
return i2c_add_driver(&aat2870_i2c_driver);
}
subsys_initcall(aat2870_init);