- 根目录:
- drivers
- iio
- accel
- mma9551_core.c
/*
* Common code for Freescale MMA955x Intelligent Sensor Platform drivers
* Copyright (c) 2014, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/delay.h>
#include <linux/iio/iio.h>
#include <linux/pm_runtime.h>
#include "mma9551_core.h"
/* Command masks for mailbox write command */
#define MMA9551_CMD_READ_VERSION_INFO 0x00
#define MMA9551_CMD_READ_CONFIG 0x10
#define MMA9551_CMD_WRITE_CONFIG 0x20
#define MMA9551_CMD_READ_STATUS 0x30
/* Mailbox read command */
#define MMA9551_RESPONSE_COCO BIT(7)
/* Error-Status codes returned in mailbox read command */
#define MMA9551_MCI_ERROR_NONE 0x00
#define MMA9551_MCI_ERROR_PARAM 0x04
#define MMA9551_MCI_INVALID_COUNT 0x19
#define MMA9551_MCI_ERROR_COMMAND 0x1C
#define MMA9551_MCI_ERROR_INVALID_LENGTH 0x21
#define MMA9551_MCI_ERROR_FIFO_BUSY 0x22
#define MMA9551_MCI_ERROR_FIFO_ALLOCATED 0x23
#define MMA9551_MCI_ERROR_FIFO_OVERSIZE 0x24
/* GPIO Application */
#define MMA9551_GPIO_POL_MSB 0x08
#define MMA9551_GPIO_POL_LSB 0x09
/* Sleep/Wake application */
#define MMA9551_SLEEP_CFG 0x06
#define MMA9551_SLEEP_CFG_SNCEN BIT(0)
#define MMA9551_SLEEP_CFG_FLEEN BIT(1)
#define MMA9551_SLEEP_CFG_SCHEN BIT(2)
/* AFE application */
#define MMA9551_AFE_X_ACCEL_REG 0x00
#define MMA9551_AFE_Y_ACCEL_REG 0x02
#define MMA9551_AFE_Z_ACCEL_REG 0x04
/* Reset/Suspend/Clear application */
#define MMA9551_RSC_RESET 0x00
#define MMA9551_RSC_OFFSET(mask) (3 - (ffs(mask) - 1) / 8)
#define MMA9551_RSC_VAL(mask) (mask >> (((ffs(mask) - 1) / 8) * 8))
/*
* A response is composed of:
* - control registers: MB0-3
* - data registers: MB4-31
*
* A request is composed of:
* - mbox to write to (always 0)
* - control registers: MB1-4
* - data registers: MB5-31
*/
#define MMA9551_MAILBOX_CTRL_REGS 4
#define MMA9551_MAX_MAILBOX_DATA_REGS 28
#define MMA9551_MAILBOX_REGS 32
#define MMA9551_I2C_READ_RETRIES 5
#define MMA9551_I2C_READ_DELAY 50 /* us */
struct mma9551_mbox_request {
u8 start_mbox; /* Always 0. */
u8 app_id;
/*
* See Section 5.3.1 of the MMA955xL Software Reference Manual.
*
* Bit 7: reserved, always 0
* Bits 6-4: command
* Bits 3-0: upper bits of register offset
*/
u8 cmd_off;
u8 lower_off;
u8 nbytes;
u8 buf[MMA9551_MAX_MAILBOX_DATA_REGS - 1];
} __packed;
struct mma9551_mbox_response {
u8 app_id;
/*
* See Section 5.3.3 of the MMA955xL Software Reference Manual.
*
* Bit 7: COCO
* Bits 6-0: Error code.
*/
u8 coco_err;
u8 nbytes;
u8 req_bytes;
u8 buf[MMA9551_MAX_MAILBOX_DATA_REGS];
} __packed;
struct mma9551_version_info {
__be32 device_id;
u8 rom_version[2];
u8 fw_version[2];
u8 hw_version[2];
u8 fw_build[2];
};
static int mma9551_transfer(struct i2c_client *client,
u8 app_id, u8 command, u16 offset,
u8 *inbytes, int num_inbytes,
u8 *outbytes, int num_outbytes)
{
struct mma9551_mbox_request req;
struct mma9551_mbox_response rsp;
struct i2c_msg in, out;
u8 req_len, err_code;
int ret, retries;
if (offset >= 1 << 12) {
dev_err(&client->dev, "register offset too large\n");
return -EINVAL;
}
req_len = 1 + MMA9551_MAILBOX_CTRL_REGS + num_inbytes;
req.start_mbox = 0;
req.app_id = app_id;
req.cmd_off = command | (offset >> 8);
req.lower_off = offset;
if (command == MMA9551_CMD_WRITE_CONFIG)
req.nbytes = num_inbytes;
else
req.nbytes = num_outbytes;
if (num_inbytes)
memcpy(req.buf, inbytes, num_inbytes);
out.addr = client->addr;
out.flags = 0;
out.len = req_len;
out.buf = (u8 *)&req;
ret = i2c_transfer(client->adapter, &out, 1);
if (ret < 0) {
dev_err(&client->dev, "i2c write failed\n");
return ret;
}
retries = MMA9551_I2C_READ_RETRIES;
do {
udelay(MMA9551_I2C_READ_DELAY);
in.addr = client->addr;
in.flags = I2C_M_RD;
in.len = sizeof(rsp);
in.buf = (u8 *)&rsp;
ret = i2c_transfer(client->adapter, &in, 1);
if (ret < 0) {
dev_err(&client->dev, "i2c read failed\n");
return ret;
}
if (rsp.coco_err & MMA9551_RESPONSE_COCO)
break;
} while (--retries > 0);
if (retries == 0) {
dev_err(&client->dev,
"timed out while waiting for command response\n");
return -ETIMEDOUT;
}
if (rsp.app_id != app_id) {
dev_err(&client->dev,
"app_id mismatch in response got %02x expected %02x\n",
rsp.app_id, app_id);
return -EINVAL;
}
err_code = rsp.coco_err & ~MMA9551_RESPONSE_COCO;
if (err_code != MMA9551_MCI_ERROR_NONE) {
dev_err(&client->dev, "read returned error %x\n", err_code);
return -EINVAL;
}
if (rsp.nbytes != rsp.req_bytes) {
dev_err(&client->dev,
"output length mismatch got %d expected %d\n",
rsp.nbytes, rsp.req_bytes);
return -EINVAL;
}
if (num_outbytes)
memcpy(outbytes, rsp.buf, num_outbytes);
return 0;
}
/**
* mma9551_read_config_byte() - read 1 configuration byte
* @client: I2C client
* @app_id: Application ID
* @reg: Application register
* @val: Pointer to store value read
*
* Read one configuration byte from the device using MMA955xL command format.
* Commands to the MMA955xL platform consist of a write followed
* by one or more reads.
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_read_config_byte(struct i2c_client *client, u8 app_id,
u16 reg, u8 *val)
{
return mma9551_transfer(client, app_id, MMA9551_CMD_READ_CONFIG,
reg, NULL, 0, val, 1);
}
EXPORT_SYMBOL(mma9551_read_config_byte);
/**
* mma9551_write_config_byte() - write 1 configuration byte
* @client: I2C client
* @app_id: Application ID
* @reg: Application register
* @val: Value to write
*
* Write one configuration byte from the device using MMA955xL command format.
* Commands to the MMA955xL platform consist of a write followed by one or
* more reads.
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_write_config_byte(struct i2c_client *client, u8 app_id,
u16 reg, u8 val)
{
return mma9551_transfer(client, app_id, MMA9551_CMD_WRITE_CONFIG, reg,
&val, 1, NULL, 0);
}
EXPORT_SYMBOL(mma9551_write_config_byte);
/**
* mma9551_read_status_byte() - read 1 status byte
* @client: I2C client
* @app_id: Application ID
* @reg: Application register
* @val: Pointer to store value read
*
* Read one status byte from the device using MMA955xL command format.
* Commands to the MMA955xL platform consist of a write followed by one or
* more reads.
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_read_status_byte(struct i2c_client *client, u8 app_id,
u16 reg, u8 *val)
{
return mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS,
reg, NULL, 0, val, 1);
}
EXPORT_SYMBOL(mma9551_read_status_byte);
/**
* mma9551_read_config_word() - read 1 config word
* @client: I2C client
* @app_id: Application ID
* @reg: Application register
* @val: Pointer to store value read
*
* Read one configuration word from the device using MMA955xL command format.
* Commands to the MMA955xL platform consist of a write followed by one or
* more reads.
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_read_config_word(struct i2c_client *client, u8 app_id,
u16 reg, u16 *val)
{
int ret;
__be16 v;
ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_CONFIG,
reg, NULL, 0, (u8 *)&v, 2);
*val = be16_to_cpu(v);
return ret;
}
EXPORT_SYMBOL(mma9551_read_config_word);
/**
* mma9551_write_config_word() - write 1 config word
* @client: I2C client
* @app_id: Application ID
* @reg: Application register
* @val: Value to write
*
* Write one configuration word from the device using MMA955xL command format.
* Commands to the MMA955xL platform consist of a write followed by one or
* more reads.
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_write_config_word(struct i2c_client *client, u8 app_id,
u16 reg, u16 val)
{
__be16 v = cpu_to_be16(val);
return mma9551_transfer(client, app_id, MMA9551_CMD_WRITE_CONFIG, reg,
(u8 *)&v, 2, NULL, 0);
}
EXPORT_SYMBOL(mma9551_write_config_word);
/**
* mma9551_read_status_word() - read 1 status word
* @client: I2C client
* @app_id: Application ID
* @reg: Application register
* @val: Pointer to store value read
*
* Read one status word from the device using MMA955xL command format.
* Commands to the MMA955xL platform consist of a write followed by one or
* more reads.
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_read_status_word(struct i2c_client *client, u8 app_id,
u16 reg, u16 *val)
{
int ret;
__be16 v;
ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS,
reg, NULL, 0, (u8 *)&v, 2);
*val = be16_to_cpu(v);
return ret;
}
EXPORT_SYMBOL(mma9551_read_status_word);
/**
* mma9551_read_config_words() - read multiple config words
* @client: I2C client
* @app_id: Application ID
* @reg: Application register
* @len: Length of array to read (in words)
* @buf: Array of words to read
*
* Read multiple configuration registers (word-sized registers).
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_read_config_words(struct i2c_client *client, u8 app_id,
u16 reg, u8 len, u16 *buf)
{
int ret, i;
__be16 be_buf[MMA9551_MAX_MAILBOX_DATA_REGS / 2];
if (len > ARRAY_SIZE(be_buf)) {
dev_err(&client->dev, "Invalid buffer size %d\n", len);
return -EINVAL;
}
ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_CONFIG,
reg, NULL, 0, (u8 *)be_buf, len * sizeof(u16));
if (ret < 0)
return ret;
for (i = 0; i < len; i++)
buf[i] = be16_to_cpu(be_buf[i]);
return 0;
}
EXPORT_SYMBOL(mma9551_read_config_words);
/**
* mma9551_read_status_words() - read multiple status words
* @client: I2C client
* @app_id: Application ID
* @reg: Application register
* @len: Length of array to read (in words)
* @buf: Array of words to read
*
* Read multiple status registers (word-sized registers).
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_read_status_words(struct i2c_client *client, u8 app_id,
u16 reg, u8 len, u16 *buf)
{
int ret, i;
__be16 be_buf[MMA9551_MAX_MAILBOX_DATA_REGS / 2];
if (len > ARRAY_SIZE(be_buf)) {
dev_err(&client->dev, "Invalid buffer size %d\n", len);
return -EINVAL;
}
ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS,
reg, NULL, 0, (u8 *)be_buf, len * sizeof(u16));
if (ret < 0)
return ret;
for (i = 0; i < len; i++)
buf[i] = be16_to_cpu(be_buf[i]);
return 0;
}
EXPORT_SYMBOL(mma9551_read_status_words);
/**
* mma9551_write_config_words() - write multiple config words
* @client: I2C client
* @app_id: Application ID
* @reg: Application register
* @len: Length of array to write (in words)
* @buf: Array of words to write
*
* Write multiple configuration registers (word-sized registers).
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_write_config_words(struct i2c_client *client, u8 app_id,
u16 reg, u8 len, u16 *buf)
{
int i;
__be16 be_buf[(MMA9551_MAX_MAILBOX_DATA_REGS - 1) / 2];
if (len > ARRAY_SIZE(be_buf)) {
dev_err(&client->dev, "Invalid buffer size %d\n", len);
return -EINVAL;
}
for (i = 0; i < len; i++)
be_buf[i] = cpu_to_be16(buf[i]);
return mma9551_transfer(client, app_id, MMA9551_CMD_WRITE_CONFIG,
reg, (u8 *)be_buf, len * sizeof(u16), NULL, 0);
}
EXPORT_SYMBOL(mma9551_write_config_words);
/**
* mma9551_update_config_bits() - update bits in register
* @client: I2C client
* @app_id: Application ID
* @reg: Application register
* @mask: Mask for the bits to update
* @val: Value of the bits to update
*
* Update bits in the given register using a bit mask.
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_update_config_bits(struct i2c_client *client, u8 app_id,
u16 reg, u8 mask, u8 val)
{
int ret;
u8 tmp, orig;
ret = mma9551_read_config_byte(client, app_id, reg, &orig);
if (ret < 0)
return ret;
tmp = orig & ~mask;
tmp |= val & mask;
if (tmp == orig)
return 0;
return mma9551_write_config_byte(client, app_id, reg, tmp);
}
EXPORT_SYMBOL(mma9551_update_config_bits);
/**
* mma9551_gpio_config() - configure gpio
* @client: I2C client
* @pin: GPIO pin to configure
* @app_id: Application ID
* @bitnum: Bit number of status register being assigned to the GPIO pin.
* @polarity: The polarity parameter is described in section 6.2.2, page 66,
* of the Software Reference Manual. Basically, polarity=0 means
* the interrupt line has the same value as the selected bit,
* while polarity=1 means the line is inverted.
*
* Assign a bit from an application’s status register to a specific GPIO pin.
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_gpio_config(struct i2c_client *client, enum mma9551_gpio_pin pin,
u8 app_id, u8 bitnum, int polarity)
{
u8 reg, pol_mask, pol_val;
int ret;
if (pin > mma9551_gpio_max) {
dev_err(&client->dev, "bad GPIO pin\n");
return -EINVAL;
}
/*
* Pin 6 is configured by regs 0x00 and 0x01, pin 7 by 0x02 and
* 0x03, and so on.
*/
reg = pin * 2;
ret = mma9551_write_config_byte(client, MMA9551_APPID_GPIO,
reg, app_id);
if (ret < 0) {
dev_err(&client->dev, "error setting GPIO app_id\n");
return ret;
}
ret = mma9551_write_config_byte(client, MMA9551_APPID_GPIO,
reg + 1, bitnum);
if (ret < 0) {
dev_err(&client->dev, "error setting GPIO bit number\n");
return ret;
}
switch (pin) {
case mma9551_gpio6:
reg = MMA9551_GPIO_POL_LSB;
pol_mask = 1 << 6;
break;
case mma9551_gpio7:
reg = MMA9551_GPIO_POL_LSB;
pol_mask = 1 << 7;
break;
case mma9551_gpio8:
reg = MMA9551_GPIO_POL_MSB;
pol_mask = 1 << 0;
break;
case mma9551_gpio9:
reg = MMA9551_GPIO_POL_MSB;
pol_mask = 1 << 1;
break;
}
pol_val = polarity ? pol_mask : 0;
ret = mma9551_update_config_bits(client, MMA9551_APPID_GPIO, reg,
pol_mask, pol_val);
if (ret < 0)
dev_err(&client->dev, "error setting GPIO polarity\n");
return ret;
}
EXPORT_SYMBOL(mma9551_gpio_config);
/**
* mma9551_read_version() - read device version information
* @client: I2C client
*
* Read version information and print device id and firmware version.
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_read_version(struct i2c_client *client)
{
struct mma9551_version_info info;
int ret;
ret = mma9551_transfer(client, MMA9551_APPID_VERSION, 0x00, 0x00,
NULL, 0, (u8 *)&info, sizeof(info));
if (ret < 0)
return ret;
dev_info(&client->dev, "device ID 0x%x, firmware version %02x.%02x\n",
be32_to_cpu(info.device_id), info.fw_version[0],
info.fw_version[1]);
return 0;
}
EXPORT_SYMBOL(mma9551_read_version);
/**
* mma9551_set_device_state() - sets HW power mode
* @client: I2C client
* @enable: Use true to power on device, false to cause the device
* to enter sleep.
*
* Set power on/off for device using the Sleep/Wake Application.
* When enable is true, power on chip and enable doze mode.
* When enable is false, enter sleep mode (device remains in the
* lowest-power mode).
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_set_device_state(struct i2c_client *client, bool enable)
{
return mma9551_update_config_bits(client, MMA9551_APPID_SLEEP_WAKE,
MMA9551_SLEEP_CFG,
MMA9551_SLEEP_CFG_SNCEN |
MMA9551_SLEEP_CFG_FLEEN |
MMA9551_SLEEP_CFG_SCHEN,
enable ? MMA9551_SLEEP_CFG_SCHEN |
MMA9551_SLEEP_CFG_FLEEN :
MMA9551_SLEEP_CFG_SNCEN);
}
EXPORT_SYMBOL(mma9551_set_device_state);
/**
* mma9551_set_power_state() - sets runtime PM state
* @client: I2C client
* @on: Use true to power on device, false to power off
*
* Resume or suspend the device using Runtime PM.
* The device will suspend after the autosuspend delay.
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_set_power_state(struct i2c_client *client, bool on)
{
#ifdef CONFIG_PM
int ret;
if (on)
ret = pm_runtime_get_sync(&client->dev);
else {
pm_runtime_mark_last_busy(&client->dev);
ret = pm_runtime_put_autosuspend(&client->dev);
}
if (ret < 0) {
dev_err(&client->dev,
"failed to change power state to %d\n", on);
if (on)
pm_runtime_put_noidle(&client->dev);
return ret;
}
#endif
return 0;
}
EXPORT_SYMBOL(mma9551_set_power_state);
/**
* mma9551_sleep() - sleep
* @freq: Application frequency
*
* Firmware applications run at a certain frequency on the
* device. Sleep for one application cycle to make sure the
* application had time to run once and initialize set values.
*/
void mma9551_sleep(int freq)
{
int sleep_val = 1000 / freq;
if (sleep_val < 20)
usleep_range(sleep_val * 1000, 20000);
else
msleep_interruptible(sleep_val);
}
EXPORT_SYMBOL(mma9551_sleep);
/**
* mma9551_read_accel_chan() - read accelerometer channel
* @client: I2C client
* @chan: IIO channel
* @val: Pointer to the accelerometer value read
* @val2: Unused
*
* Read accelerometer value for the specified channel.
*
* Locking note: This function must be called with the device lock held.
* Locking is not handled inside the function. Callers should ensure they
* serialize access to the HW.
*
* Returns: IIO_VAL_INT on success, negative value on failure.
*/
int mma9551_read_accel_chan(struct i2c_client *client,
const struct iio_chan_spec *chan,
int *val, int *val2)
{
u16 reg_addr;
s16 raw_accel;
int ret;
switch (chan->channel2) {
case IIO_MOD_X:
reg_addr = MMA9551_AFE_X_ACCEL_REG;
break;
case IIO_MOD_Y:
reg_addr = MMA9551_AFE_Y_ACCEL_REG;
break;
case IIO_MOD_Z:
reg_addr = MMA9551_AFE_Z_ACCEL_REG;
break;
default:
return -EINVAL;
}
ret = mma9551_set_power_state(client, true);
if (ret < 0)
return ret;
ret = mma9551_read_status_word(client, MMA9551_APPID_AFE,
reg_addr, &raw_accel);
if (ret < 0)
goto out_poweroff;
*val = raw_accel;
ret = IIO_VAL_INT;
out_poweroff:
mma9551_set_power_state(client, false);
return ret;
}
EXPORT_SYMBOL(mma9551_read_accel_chan);
/**
* mma9551_read_accel_scale() - read accelerometer scale
* @val: Pointer to the accelerometer scale (int value)
* @val2: Pointer to the accelerometer scale (micro value)
*
* Read accelerometer scale.
*
* Returns: IIO_VAL_INT_PLUS_MICRO.
*/
int mma9551_read_accel_scale(int *val, int *val2)
{
*val = 0;
*val2 = 2440;
return IIO_VAL_INT_PLUS_MICRO;
}
EXPORT_SYMBOL(mma9551_read_accel_scale);
/**
* mma9551_app_reset() - reset application
* @client: I2C client
* @app_mask: Application to reset
*
* Reset the given application (using the Reset/Suspend/Clear
* Control Application)
*
* Returns: 0 on success, negative value on failure.
*/
int mma9551_app_reset(struct i2c_client *client, u32 app_mask)
{
return mma9551_write_config_byte(client, MMA9551_APPID_RSC,
MMA9551_RSC_RESET +
MMA9551_RSC_OFFSET(app_mask),
MMA9551_RSC_VAL(app_mask));
}
EXPORT_SYMBOL(mma9551_app_reset);
MODULE_AUTHOR("Irina Tirdea <irina.tirdea@intel.com>");
MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("MMA955xL sensors core");