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incubator-nuttx/drivers/usbmisc/fusb303.c

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/****************************************************************************
* drivers/usbmisc/fusb303.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <assert.h>
#include <errno.h>
#include <poll.h>
#include <debug.h>
#include <nuttx/compiler.h>
#include <nuttx/fs/fs.h>
#include <nuttx/kmalloc.h>
#include <nuttx/mutex.h>
#include <nuttx/i2c/i2c_master.h>
#include <nuttx/usb/fusb303.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifdef CONFIG_DEBUG_FUSB303
# define fusb303_err(x, ...) _err(x, ##__VA_ARGS__)
# define fusb303_info(x, ...) _info(x, ##__VA_ARGS__)
#else
# define fusb303_err(x, ...) uerr(x, ##__VA_ARGS__)
# define fusb303_info(x, ...) uinfo(x, ##__VA_ARGS__)
#endif
#ifndef CONFIG_FUSB303_I2C_FREQUENCY
# define CONFIG_FUSB303_I2C_FREQUENCY 400000
#endif
/* Other macros */
#define FUSB303_I2C_RETRIES 10
#define FUSB303_ALL_INTR (INTERRUPT_ATTACH | INTERRUPT_DETACH | \
INTERRUPT_BC_LVL | INTERRUPT_AUTOSNK | \
INTERRUPT_VBUS_CHG | INTERRUPT_FAULT | \
INTERRUPT_ORIENT)
#define FUSB303_ALL_INTR1 (INTERRUPT1_REMEDY | INTERRUPT1_FRC_SUCC | \
INTERRUPT1_FRC_FAIL | INTERRUPT1_REM_FAIL | \
INTERRUPT1_REM_VBON | INTERRUPT1_REM_VBOFF)
/* Debug */
#ifdef CONFIG_DEBUG_FUSB303
# define DUMPREG(priv, x) \
do \
{ \
int ret = fusb303_getreg((priv), (x)); \
if (ret < 0) \
{ \
fusb303_err("ERROR: Failed to read %s(0x%02X)\n", #x, (x)); \
} \
else \
{ \
fusb303_info("%s(0x%02X): 0x%02X\n", #x, (x), ret); \
} \
} \
while(0)
#endif
/****************************************************************************
* Private Data Types
****************************************************************************/
struct fusb303_dev_s
{
FAR struct i2c_master_s *i2c; /* I2C interface */
uint8_t addr; /* I2C address */
volatile bool int_pending; /* Interrupt received but handled */
mutex_t devlock; /* Manages exclusive access */
FAR struct fusb303_config_s *config; /* Platform specific configuration */
FAR struct pollfd *fds[CONFIG_FUSB303_NPOLLWAITERS];
};
/****************************************************************************
* Private Function prototypes
****************************************************************************/
#ifdef CONFIG_DEBUG_FUSB303
static int fusb303_dumpregs(FAR const char *funcname,
FAR struct fusb303_dev_s *priv);
#endif
static int fusb303_open(FAR struct file *filep);
static int fusb303_close(FAR struct file *filep);
static ssize_t fusb303_read(FAR struct file *, FAR char *, size_t);
static ssize_t fusb303_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen);
static int fusb303_ioctl(FAR struct file *filep, int cmd, unsigned long arg);
static int fusb303_poll(FAR struct file *filep, FAR struct pollfd *fds,
bool setup);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct file_operations g_fusb303ops =
{
fusb303_open, /* open */
fusb303_close, /* close */
fusb303_read, /* read */
fusb303_write, /* write */
NULL, /* seek */
fusb303_ioctl, /* ioctl */
NULL, /* mmap */
NULL, /* truncate */
fusb303_poll /* poll */
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: fusb303_getreg
*
* Description:
* Read from an 8-bit FUSB303 register
*
* Input Parameters:
* priv - pointer to FUSB303 Private Structure
* reg - register to read
*
* Returned Value:
* Returns positive register value in case of success, otherwise ERROR
*
****************************************************************************/
static int fusb303_getreg(FAR struct fusb303_dev_s *priv, uint8_t reg)
{
int ret = -EIO;
int retries;
uint8_t regval;
struct i2c_msg_s msg[2];
DEBUGASSERT(priv);
msg[0].frequency = CONFIG_FUSB303_I2C_FREQUENCY;
msg[0].addr = priv->addr;
msg[0].flags = 0;
msg[0].buffer = &reg;
msg[0].length = 1;
msg[1].frequency = CONFIG_FUSB303_I2C_FREQUENCY;
msg[1].addr = priv->addr;
msg[1].flags = I2C_M_READ;
msg[1].buffer = &regval;
msg[1].length = 1;
/* Perform the transfer */
for (retries = 0; retries < FUSB303_I2C_RETRIES; retries++)
{
ret = I2C_TRANSFER(priv->i2c, msg, 2);
if (ret >= 0)
{
fusb303_info("reg:%02X, value:%02X\n", reg, regval);
return regval;
}
else
{
/* Some error. Try to reset I2C bus and keep trying. */
#ifdef CONFIG_I2C_RESET
if (retries == FUSB303_I2C_RETRIES - 1)
{
break;
}
ret = I2C_RESET(priv->i2c);
if (ret < 0)
{
fusb303_err("ERROR: I2C_RESET failed: %d\n", ret);
return ret;
}
#endif
}
}
fusb303_info("reg:%02X, error:%d\n", reg, ret);
return ret;
}
/****************************************************************************
* Name: fusb303_putreg
*
* Description:
* Write a value to an 8-bit FUSB303 register
*
* Input Parameters:
* priv - pointer to FUSB303 Private Structure
* regaddr - register to read
* regval - value to be written
*
* Returned Value:
* None
*
****************************************************************************/
static int fusb303_putreg(FAR struct fusb303_dev_s *priv, uint8_t regaddr,
uint8_t regval)
{
int ret = -EIO;
int retries;
struct i2c_msg_s msg;
uint8_t txbuffer[2];
/* Setup to the data to be transferred (register address and data). */
txbuffer[0] = regaddr;
txbuffer[1] = regval;
/* Setup 8-bit FUSB303 address write message */
msg.frequency = CONFIG_FUSB303_I2C_FREQUENCY;
msg.addr = priv->addr;
msg.flags = 0;
msg.buffer = txbuffer;
msg.length = 2;
/* Perform the transfer */
for (retries = 0; retries < FUSB303_I2C_RETRIES; retries++)
{
ret = I2C_TRANSFER(priv->i2c, &msg, 1);
if (ret == OK)
{
fusb303_info("reg:%02X, value:%02X\n", regaddr, regval);
return OK;
}
else
{
/* Some error. Try to reset I2C bus and keep trying. */
#ifdef CONFIG_I2C_RESET
if (retries == FUSB303_I2C_RETRIES - 1)
{
break;
}
ret = I2C_RESET(priv->i2c);
if (ret < 0)
{
fusb303_err("ERROR: I2C_RESET failed: %d\n", ret);
return ret;
}
#endif
}
}
fusb303_err("ERROR: failed reg:%02X, value:%02X, error:%d\n",
regaddr, regval, ret);
return ret;
}
/****************************************************************************
* Name: fusb303_dumpregs
*
* Description:
* Dump FUSB303 registers
*
* Input Parameters:
* priv - pointer to FUSB303 Private Structure
*
* Returned Value:
* None
*
****************************************************************************/
#ifdef CONFIG_DEBUG_FUSB303
static int noinline_function fusb303_dumpregs(FAR const char *funcname,
FAR struct fusb303_dev_s *priv)
{
fusb303_info("'%s':\n", funcname);
DUMPREG(priv, FUSB303_DEV_ID_REG);
DUMPREG(priv, FUSB303_DEV_TYPE_REG);
DUMPREG(priv, FUSB303_PORTROLE_REG);
DUMPREG(priv, FUSB303_CONTROL_REG);
DUMPREG(priv, FUSB303_CONTROL1_REG);
DUMPREG(priv, FUSB303_MANUAL_REG);
DUMPREG(priv, FUSB303_RESET_REG);
DUMPREG(priv, FUSB303_MASK_REG);
DUMPREG(priv, FUSB303_MASK1_REG);
DUMPREG(priv, FUSB303_STATUS_REG);
DUMPREG(priv, FUSB303_STATUS1_REG);
DUMPREG(priv, FUSB303_TYPE_REG);
DUMPREG(priv, FUSB303_INTERRUPT_REG);
DUMPREG(priv, FUSB303_INTERRUPT1_REG);
return OK;
}
#endif /* CONFIG_DEBUG_FUSB303 */
/****************************************************************************
* Name: fusb303_read_device_id
*
* Description:
* Read device version, revision ID and type.
*
****************************************************************************/
static int fusb303_read_device_id(FAR struct fusb303_dev_s *priv,
FAR uint8_t *dev_id, FAR uint8_t *dev_type)
{
int ret;
ret = fusb303_getreg(priv, FUSB303_DEV_ID_REG);
if (ret < 0)
{
fusb303_err("ERROR: Failed to read device ID\n");
return -EIO;
}
if (dev_id != NULL)
{
*dev_id = ret;
}
ret = fusb303_getreg(priv, FUSB303_DEV_TYPE_REG);
if (ret < 0)
{
fusb303_err("ERROR: Failed to read device type\n");
return -EIO;
}
if (dev_type != NULL)
{
*dev_type = ret;
}
return ret;
}
/****************************************************************************
* Name: fusb303_clear_interrupts
*
* Description:
* Clear interrupts from FUSB303 chip
*
****************************************************************************/
static int fusb303_clear_interrupts(FAR struct fusb303_dev_s *priv)
{
int ret;
ret = fusb303_putreg(priv, FUSB303_INTERRUPT_REG, FUSB303_ALL_INTR);
if (ret < 0)
{
fusb303_err("ERROR: Failed to clear interrupts\n");
return -EIO;
}
ret = fusb303_putreg(priv, FUSB303_INTERRUPT1_REG, FUSB303_ALL_INTR1);
if (ret < 0)
{
fusb303_err("ERROR: Failed to clear interrupts\n");
return -EIO;
}
return ret;
}
/****************************************************************************
* Name: fusb303_setup
*
* Description:
* Setup FUSB303 chip
*
****************************************************************************/
static int fusb303_setup(FAR struct fusb303_dev_s *priv,
struct fusb303_setup_s *setup)
{
int ret = OK;
uint8_t regval;
fusb303_info("drp_tgl:%02X, host_curr:%02X\n"
"dcable_en: %d, remedy_en: %d, auto_snk_en: %d\n"
"global_int: %d, mask: %02X, mask1: %02X\n",
setup->drp_toggle_timing, setup->host_current,
(int)setup->dcable_en, (int)setup->remedy_en,
(int)setup->auto_snk_en, (int)setup->global_int_mask,
setup->int_mask, setup->int_mask1);
/* Enable chip in I2C mode. */
ret = fusb303_getreg(priv, FUSB303_CONTROL1_REG);
if (ret < 0)
{
fusb303_err("ERROR: Failed to enable chip\n");
goto err_out;
}
/* TODO: no way to change AUTO_SNK_TH or TCCDEB at the moment. */
regval = (uint8_t)ret | CONTROL1_ENABLE;
if (setup->auto_snk_en)
{
regval |= CONTROL1_AUTO_SNK_EN;
}
else
{
regval &= ~CONTROL1_AUTO_SNK_EN;
}
if (setup->remedy_en)
{
regval |= CONTROL1_REMEDY_EN;
}
else
{
regval &= ~CONTROL1_REMEDY_EN;
}
ret = fusb303_putreg(priv, FUSB303_CONTROL1_REG, regval);
if (ret < 0)
{
fusb303_err("ERROR: Failed to enable chip\n");
goto err_out;
}
/* Setup the interrupt masks and remaining settings. */
ret = fusb303_putreg(priv, FUSB303_MASK_REG, setup->int_mask);
if (ret < 0)
{
fusb303_err("ERROR: Failed to write mask register\n");
goto err_out;
}
ret = fusb303_putreg(priv, FUSB303_MASK1_REG, setup->int_mask1);
if (ret < 0)
{
fusb303_err("ERROR: Failed to write mask register\n");
goto err_out;
}
/* Interrupts can happen only after unmasking global_int_mask */
regval = setup->drp_toggle_timing | setup->host_current |
setup->global_int_mask;
if (setup->dcable_en)
{
regval |= CONTROL_DCABLE_EN;
}
ret = fusb303_putreg(priv, FUSB303_CONTROL_REG, regval);
if (ret < 0)
{
fusb303_err("ERROR: Failed to write control register\n");
goto err_out;
}
err_out:
#ifdef CONFIG_DEBUG_FUSB303
fusb303_dumpregs("fusb303_setup", priv);
#endif
return ret;
}
/****************************************************************************
* Name: fusb303_set_mode
*
* Description:
* Configure supported device modes (sink, source, DRP, accessory)
*
****************************************************************************/
static int fusb303_set_mode(FAR struct fusb303_dev_s *priv,
enum fusb303_mode_e mode)
{
int ret;
if (mode > MODE_ORIENTDEB)
{
return -EINVAL;
}
ret = fusb303_putreg(priv, FUSB303_PORTROLE_REG, mode);
if (ret < 0)
{
fusb303_err("ERROR: Failed to set portrole\n");
ret = -EIO;
}
return ret;
}
/****************************************************************************
* Name: fusb303_set_state
*
* Description:
* Force device in specified state
*
****************************************************************************/
static int fusb303_set_state(FAR struct fusb303_dev_s *priv,
enum fusb303_manual_e state)
{
int ret;
if (state > MANUAL_FORCE_SRC)
{
return -EINVAL;
}
ret = fusb303_putreg(priv, FUSB303_MANUAL_REG, state);
if (ret < 0)
{
fusb303_err("ERROR: Failed to set state\n");
ret = -EIO;
}
return ret;
}
/****************************************************************************
* Name: fusb303_read_status
*
* Description:
* Read status register
*
****************************************************************************/
static int fusb303_read_status(FAR struct fusb303_dev_s *priv,
FAR uint8_t *arg)
{
int ret;
ret = fusb303_getreg(priv, FUSB303_STATUS_REG);
if (ret < 0)
{
fusb303_err("ERROR: Failed to read status\n");
return -EIO;
}
*arg = ret;
return OK;
}
/****************************************************************************
* Name: fusb303_read_devtype
*
* Description:
* Read type of attached device
*
****************************************************************************/
static int fusb303_read_devtype(FAR struct fusb303_dev_s *priv,
FAR uint8_t *arg)
{
int ret;
ret = fusb303_getreg(priv, FUSB303_TYPE_REG);
if (ret < 0)
{
fusb303_err("ERROR: Failed to read type\n");
return -EIO;
}
*arg = ret;
return OK;
}
/****************************************************************************
* Name: fusb303_reset
*
* Description:
* Reset FUSB303 HW and clear I2C registers
*
****************************************************************************/
static int fusb303_reset(FAR struct fusb303_dev_s *priv)
{
int ret;
ret = fusb303_putreg(priv, FUSB303_RESET_REG, RESET_SW_RES);
if (ret < 0)
{
fusb303_err("ERROR: Failed to reset chip\n");
ret = -EIO;
}
/* tRESET max 100 ms. */
up_mdelay(100);
return ret;
}
/****************************************************************************
* Name: fusb303_open
*
* Description:
* This function is called whenever the FUSB303 device is opened.
*
****************************************************************************/
static int fusb303_open(FAR struct file *filep)
{
FAR struct inode *inode = filep->f_inode;
FAR struct fusb303_dev_s *priv = inode->i_private;
uint8_t dev_id;
uint8_t dev_type;
int ret;
ret = nxmutex_lock(&priv->devlock);
if (ret < 0)
{
return ret;
}
/* Probe device */
ret = fusb303_read_device_id(priv, &dev_id, &dev_type);
if (ret < 0)
{
fusb303_err("ERROR: No response at given address 0x%02X\n",
priv->addr);
ret = -EFAULT;
}
else
{
fusb303_info("device id: 0x%02X type: 0x%02X\n", dev_id, dev_type);
fusb303_clear_interrupts(priv);
priv->config->irq_enable(priv->config, true);
}
nxmutex_unlock(&priv->devlock);
return ret;
}
/****************************************************************************
* Name: fusb303_close
*
* Description:
* This routine is called when the FUSB303 device is closed.
*
****************************************************************************/
static int fusb303_close(FAR struct file *filep)
{
FAR struct inode *inode = filep->f_inode;
FAR struct fusb303_dev_s *priv = inode->i_private;
int ret;
ret = nxmutex_lock(&priv->devlock);
if (ret < 0)
{
return ret;
}
priv->config->irq_enable(priv->config, false);
nxmutex_unlock(&priv->devlock);
return OK;
}
/****************************************************************************
* Name: fusb303_read
*
* Description:
* This routine is called when the FUSB303 device is read.
*
****************************************************************************/
static ssize_t fusb303_read(FAR struct file *filep, FAR char *buffer,
size_t buflen)
{
FAR struct inode *inode = filep->f_inode;
FAR struct fusb303_dev_s *priv = inode->i_private;
FAR struct fusb303_result_s *ptr;
irqstate_t flags;
int ret;
if (buflen < sizeof(struct fusb303_result_s))
{
return 0;
}
ptr = (struct fusb303_result_s *)buffer;
ret = nxmutex_lock(&priv->devlock);
if (ret < 0)
{
return ret;
}
flags = enter_critical_section();
priv->int_pending = false;
leave_critical_section(flags);
ptr->status = fusb303_getreg(priv, FUSB303_STATUS_REG);
ptr->status1 = fusb303_getreg(priv, FUSB303_STATUS1_REG);
ptr->dev_type = fusb303_getreg(priv, FUSB303_TYPE_REG);
#ifdef CONFIG_DEBUG_FUSB303
fusb303_dumpregs("fusb303_read", priv);
#endif
fusb303_clear_interrupts(priv);
nxmutex_unlock(&priv->devlock);
return sizeof(struct fusb303_result_s);
}
/****************************************************************************
* Name: fusb303_write
*
* Description:
* This routine is called when the FUSB303 device is written to.
*
****************************************************************************/
static ssize_t fusb303_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen)
{
ssize_t length = 0;
return length;
}
/****************************************************************************
* Name: fusb303_ioctl
*
* Description:
* This routine is called when ioctl function call is performed for
* the FUSB303 device.
*
****************************************************************************/
static int fusb303_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
{
FAR struct inode *inode = filep->f_inode;
FAR struct fusb303_dev_s *priv = inode->i_private;
int ret;
ret = nxmutex_lock(&priv->devlock);
if (ret < 0)
{
return ret;
}
fusb303_info("cmd: 0x%02X, arg:%lu\n", cmd, arg);
switch (cmd)
{
case USBCIOC_READ_DEVID:
{
ret = fusb303_read_device_id(priv, (FAR uint8_t *)arg, NULL);
}
break;
case USBCIOC_SETUP:
{
ret = fusb303_setup(priv, (struct fusb303_setup_s *)arg);
}
break;
case USBCIOC_SET_MODE:
{
ret = fusb303_set_mode(priv, (uint8_t)arg);
}
break;
case USBCIOC_SET_STATE:
{
ret = fusb303_set_state(priv, (uint8_t)arg);
}
break;
case USBCIOC_READ_STATUS:
{
ret = fusb303_read_status(priv, (FAR uint8_t *)arg);
}
break;
case USBCIOC_READ_DEVTYPE:
{
ret = fusb303_read_devtype(priv, (FAR uint8_t *)arg);
}
break;
case USBCIOC_RESET:
{
ret = fusb303_reset(priv);
}
break;
default:
{
fusb303_err("ERROR: Unrecognized cmd: %d\n", cmd);
ret = -ENOTTY;
}
break;
}
nxmutex_unlock(&priv->devlock);
return ret;
}
/****************************************************************************
* Name: fusb303_poll
*
* Description:
* This routine is called during FUSB303 device poll
*
****************************************************************************/
static int fusb303_poll(FAR struct file *filep, FAR struct pollfd *fds,
bool setup)
{
FAR struct inode *inode;
FAR struct fusb303_dev_s *priv;
irqstate_t flags;
int ret = OK;
int i;
DEBUGASSERT(fds);
inode = filep->f_inode;
DEBUGASSERT(inode->i_private);
priv = inode->i_private;
ret = nxmutex_lock(&priv->devlock);
if (ret < 0)
{
return ret;
}
if (setup)
{
/* Ignore waits that do not include POLLIN */
if ((fds->events & POLLIN) == 0)
{
ret = -EDEADLK;
goto out;
}
/* This is a request to set up the poll. Find an available
* slot for the poll structure reference.
*/
for (i = 0; i < CONFIG_FUSB303_NPOLLWAITERS; i++)
{
/* Find an available slot */
if (!priv->fds[i])
{
/* Bind the poll structure and this slot */
priv->fds[i] = fds;
fds->priv = &priv->fds[i];
break;
}
}
if (i >= CONFIG_FUSB303_NPOLLWAITERS)
{
fds->priv = NULL;
ret = -EBUSY;
goto out;
}
flags = enter_critical_section();
if (priv->int_pending)
{
poll_notify(&fds, 1, POLLIN);
}
leave_critical_section(flags);
}
else if (fds->priv)
{
/* This is a request to tear down the poll. */
FAR struct pollfd **slot = (FAR struct pollfd **)fds->priv;
DEBUGASSERT(slot != NULL);
/* Remove all memory of the poll setup */
*slot = NULL;
fds->priv = NULL;
}
out:
nxmutex_unlock(&priv->devlock);
return ret;
}
/****************************************************************************
* Name: fusb303_callback
*
* Description:
* FUSB303 interrupt handler
*
****************************************************************************/
static int fusb303_int_handler(int irq, FAR void *context, FAR void *arg)
{
FAR struct fusb303_dev_s *priv = (FAR struct fusb303_dev_s *)arg;
irqstate_t flags;
DEBUGASSERT(priv != NULL);
flags = enter_critical_section();
priv->int_pending = true;
poll_notify(priv->fds, CONFIG_FUSB303_NPOLLWAITERS, POLLIN);
leave_critical_section(flags);
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
int fusb303_register(FAR const char *devpath, FAR struct i2c_master_s *i2c,
uint8_t addr, FAR struct fusb303_config_s *config)
{
FAR struct fusb303_dev_s *priv;
int ret;
DEBUGASSERT(devpath != NULL && i2c != NULL && config != NULL);
/* Initialize the FUSB303 device structure */
priv = (FAR struct fusb303_dev_s *)
kmm_zalloc(sizeof(struct fusb303_dev_s));
if (!priv)
{
fusb303_err("ERROR: Failed to allocate instance\n");
return -ENOMEM;
}
/* Initialize device structure mutex */
nxmutex_init(&priv->devlock);
priv->int_pending = false;
priv->i2c = i2c;
priv->addr = addr;
priv->config = config;
/* Register the character driver */
ret = register_driver(devpath, &g_fusb303ops, 0666, priv);
if (ret < 0)
{
fusb303_err("ERROR: Failed to register driver: %d\n", ret);
goto errout_with_priv;
}
/* Prepare interrupt line and handler. */
if (priv->config->irq_clear)
{
priv->config->irq_clear(config);
}
priv->config->irq_attach(config, fusb303_int_handler, priv);
priv->config->irq_enable(config, false);
return OK;
errout_with_priv:
nxmutex_destroy(&priv->devlock);
kmm_free(priv);
return ret;
}
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