Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  Silicon Labs C2 port core Linux support
 *
 *  Copyright (c) 2007 Rodolfo Giometti <giometti@linux.it>
 *  Copyright (c) 2007 Eurotech S.p.A. <info@eurotech.it>
 */
 
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/ctype.h>
#include <linux/delay.h>
#include <linux/idr.h>
#include <linux/sched.h>
#include <linux/slab.h>
 
#include <linux/c2port.h>
 
#define DRIVER_NAME             "c2port"
#define DRIVER_VERSION          "0.51.0"
 
static DEFINE_SPINLOCK(c2port_idr_lock);
static DEFINE_IDR(c2port_idr);
 
/*
 * Local variables
 */
 
static struct class *c2port_class;
 
/*
 * C2 registers & commands defines
 */
 
/* C2 registers */
#define C2PORT_DEVICEID		0x00
#define C2PORT_REVID		0x01
#define C2PORT_FPCTL		0x02
#define C2PORT_FPDAT		0xB4
 
/* C2 interface commands */
#define C2PORT_GET_VERSION	0x01
#define C2PORT_DEVICE_ERASE	0x03
#define C2PORT_BLOCK_READ	0x06
#define C2PORT_BLOCK_WRITE	0x07
#define C2PORT_PAGE_ERASE	0x08
 
/* C2 status return codes */
#define C2PORT_INVALID_COMMAND	0x00
#define C2PORT_COMMAND_FAILED	0x02
#define C2PORT_COMMAND_OK	0x0d
 
/*
 * C2 port low level signal managements
 */
 
static void c2port_reset(struct c2port_device *dev)
{
<------>struct c2port_ops *ops = dev->ops;
 
<------>/* To reset the device we have to keep clock line low for at least
<------> * 20us.
<------> */
<------>local_irq_disable();
<------>ops->c2ck_set(dev, 0);
<------>udelay(25);
<------>ops->c2ck_set(dev, 1);
<------>local_irq_enable();
 
<------>udelay(1);
}
 
static void c2port_strobe_ck(struct c2port_device *dev)
{
<------>struct c2port_ops *ops = dev->ops;
 
<------>/* During hi-low-hi transition we disable local IRQs to avoid
<------> * interructions since C2 port specification says that it must be
<------> * shorter than 5us, otherwise the microcontroller may consider
<------> * it as a reset signal!
<------> */
<------>local_irq_disable();
<------>ops->c2ck_set(dev, 0);
<------>udelay(1);
<------>ops->c2ck_set(dev, 1);
<------>local_irq_enable();
 
<------>udelay(1);
}
 
/*
 * C2 port basic functions
 */
 
static void c2port_write_ar(struct c2port_device *dev, u8 addr)
{
<------>struct c2port_ops *ops = dev->ops;
<------>int i;
 
<------>/* START field */
<------>c2port_strobe_ck(dev);
 
<------>/* INS field (11b, LSB first) */
<------>ops->c2d_dir(dev, 0);
<------>ops->c2d_set(dev, 1);
<------>c2port_strobe_ck(dev);
<------>ops->c2d_set(dev, 1);
<------>c2port_strobe_ck(dev);
 
<------>/* ADDRESS field */
<------>for (i = 0; i < 8; i++) {
<------><------>ops->c2d_set(dev, addr & 0x01);
<------><------>c2port_strobe_ck(dev);
 
<------><------>addr >>= 1;
<------>}
 
<------>/* STOP field */
<------>ops->c2d_dir(dev, 1);
<------>c2port_strobe_ck(dev);
}
 
static int c2port_read_ar(struct c2port_device *dev, u8 *addr)
{
<------>struct c2port_ops *ops = dev->ops;
<------>int i;
 
<------>/* START field */
<------>c2port_strobe_ck(dev);
 
<------>/* INS field (10b, LSB first) */
<------>ops->c2d_dir(dev, 0);
<------>ops->c2d_set(dev, 0);
<------>c2port_strobe_ck(dev);
<------>ops->c2d_set(dev, 1);
<------>c2port_strobe_ck(dev);
 
<------>/* ADDRESS field */
<------>ops->c2d_dir(dev, 1);
<------>*addr = 0;
<------>for (i = 0; i < 8; i++) {
<------><------>*addr >>= 1;	/* shift in 8-bit ADDRESS field LSB first */
 
<------><------>c2port_strobe_ck(dev);
<------><------>if (ops->c2d_get(dev))
<------><------><------>*addr |= 0x80;
<------>}
 
<------>/* STOP field */
<------>c2port_strobe_ck(dev);
 
<------>return 0;
}
 
static int c2port_write_dr(struct c2port_device *dev, u8 data)
{
<------>struct c2port_ops *ops = dev->ops;
<------>int timeout, i;
 
<------>/* START field */
<------>c2port_strobe_ck(dev);
 
<------>/* INS field (01b, LSB first) */
<------>ops->c2d_dir(dev, 0);
<------>ops->c2d_set(dev, 1);
<------>c2port_strobe_ck(dev);
<------>ops->c2d_set(dev, 0);
<------>c2port_strobe_ck(dev);
 
<------>/* LENGTH field (00b, LSB first -> 1 byte) */
<------>ops->c2d_set(dev, 0);
<------>c2port_strobe_ck(dev);
<------>ops->c2d_set(dev, 0);
<------>c2port_strobe_ck(dev);
 
<------>/* DATA field */
<------>for (i = 0; i < 8; i++) {
<------><------>ops->c2d_set(dev, data & 0x01);
<------><------>c2port_strobe_ck(dev);
 
<------><------>data >>= 1;
<------>}
 
<------>/* WAIT field */
<------>ops->c2d_dir(dev, 1);
<------>timeout = 20;
<------>do {
<------><------>c2port_strobe_ck(dev);
<------><------>if (ops->c2d_get(dev))
<------><------><------>break;
 
<------><------>udelay(1);
<------>} while (--timeout > 0);
<------>if (timeout == 0)
<------><------>return -EIO;
 
<------>/* STOP field */
<------>c2port_strobe_ck(dev);
 
<------>return 0;
}
 
static int c2port_read_dr(struct c2port_device *dev, u8 *data)
{
<------>struct c2port_ops *ops = dev->ops;
<------>int timeout, i;
 
<------>/* START field */
<------>c2port_strobe_ck(dev);
 
<------>/* INS field (00b, LSB first) */
<------>ops->c2d_dir(dev, 0);
<------>ops->c2d_set(dev, 0);
<------>c2port_strobe_ck(dev);
<------>ops->c2d_set(dev, 0);
<------>c2port_strobe_ck(dev);
 
<------>/* LENGTH field (00b, LSB first -> 1 byte) */
<------>ops->c2d_set(dev, 0);
<------>c2port_strobe_ck(dev);
<------>ops->c2d_set(dev, 0);
<------>c2port_strobe_ck(dev);
 
<------>/* WAIT field */
<------>ops->c2d_dir(dev, 1);
<------>timeout = 20;
<------>do {
<------><------>c2port_strobe_ck(dev);
<------><------>if (ops->c2d_get(dev))
<------><------><------>break;
 
<------><------>udelay(1);
<------>} while (--timeout > 0);
<------>if (timeout == 0)
<------><------>return -EIO;
 
<------>/* DATA field */
<------>*data = 0;
<------>for (i = 0; i < 8; i++) {
<------><------>*data >>= 1;	/* shift in 8-bit DATA field LSB first */
 
<------><------>c2port_strobe_ck(dev);
<------><------>if (ops->c2d_get(dev))
<------><------><------>*data |= 0x80;
<------>}
 
<------>/* STOP field */
<------>c2port_strobe_ck(dev);
 
<------>return 0;
}
 
static int c2port_poll_in_busy(struct c2port_device *dev)
{
<------>u8 addr;
<------>int ret, timeout = 20;
 
<------>do {
<------><------>ret = (c2port_read_ar(dev, &addr));
<------><------>if (ret < 0)
<------><------><------>return -EIO;
 
<------><------>if (!(addr & 0x02))
<------><------><------>break;
 
<------><------>udelay(1);
<------>} while (--timeout > 0);
<------>if (timeout == 0)
<------><------>return -EIO;
 
<------>return 0;
}
 
static int c2port_poll_out_ready(struct c2port_device *dev)
{
<------>u8 addr;
<------>int ret, timeout = 10000; /* erase flash needs long time... */
 
<------>do {
<------><------>ret = (c2port_read_ar(dev, &addr));
<------><------>if (ret < 0)
<------><------><------>return -EIO;
 
<------><------>if (addr & 0x01)
<------><------><------>break;
 
<------><------>udelay(1);
<------>} while (--timeout > 0);
<------>if (timeout == 0)
<------><------>return -EIO;
 
<------>return 0;
}
 
/*
 * sysfs methods
 */
 
static ssize_t c2port_show_name(struct device *dev,
<------><------><------><------>struct device_attribute *attr, char *buf)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
 
<------>return sprintf(buf, "%s\n", c2dev->name);
}
static DEVICE_ATTR(name, 0444, c2port_show_name, NULL);
 
static ssize_t c2port_show_flash_blocks_num(struct device *dev,
<------><------><------><------>struct device_attribute *attr, char *buf)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
<------>struct c2port_ops *ops = c2dev->ops;
 
<------>return sprintf(buf, "%d\n", ops->blocks_num);
}
static DEVICE_ATTR(flash_blocks_num, 0444, c2port_show_flash_blocks_num, NULL);
 
static ssize_t c2port_show_flash_block_size(struct device *dev,
<------><------><------><------>struct device_attribute *attr, char *buf)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
<------>struct c2port_ops *ops = c2dev->ops;
 
<------>return sprintf(buf, "%d\n", ops->block_size);
}
static DEVICE_ATTR(flash_block_size, 0444, c2port_show_flash_block_size, NULL);
 
static ssize_t c2port_show_flash_size(struct device *dev,
<------><------><------><------>struct device_attribute *attr, char *buf)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
<------>struct c2port_ops *ops = c2dev->ops;
 
<------>return sprintf(buf, "%d\n", ops->blocks_num * ops->block_size);
}
static DEVICE_ATTR(flash_size, 0444, c2port_show_flash_size, NULL);
 
static ssize_t access_show(struct device *dev, struct device_attribute *attr,
<------><------><------>   char *buf)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
 
<------>return sprintf(buf, "%d\n", c2dev->access);
}
 
static ssize_t access_store(struct device *dev, struct device_attribute *attr,
<------><------><------>    const char *buf, size_t count)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
<------>struct c2port_ops *ops = c2dev->ops;
<------>int status, ret;
 
<------>ret = sscanf(buf, "%d", &status);
<------>if (ret != 1)
<------><------>return -EINVAL;
 
<------>mutex_lock(&c2dev->mutex);
 
<------>c2dev->access = !!status;
 
<------>/* If access is "on" clock should be HIGH _before_ setting the line
<------> * as output and data line should be set as INPUT anyway */
<------>if (c2dev->access)
<------><------>ops->c2ck_set(c2dev, 1);
<------>ops->access(c2dev, c2dev->access);
<------>if (c2dev->access)
<------><------>ops->c2d_dir(c2dev, 1);
 
<------>mutex_unlock(&c2dev->mutex);
 
<------>return count;
}
static DEVICE_ATTR_RW(access);
 
static ssize_t c2port_store_reset(struct device *dev,
<------><------><------><------>struct device_attribute *attr,
<------><------><------><------>const char *buf, size_t count)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
 
<------>/* Check the device access status */
<------>if (!c2dev->access)
<------><------>return -EBUSY;
 
<------>mutex_lock(&c2dev->mutex);
 
<------>c2port_reset(c2dev);
<------>c2dev->flash_access = 0;
 
<------>mutex_unlock(&c2dev->mutex);
 
<------>return count;
}
static DEVICE_ATTR(reset, 0200, NULL, c2port_store_reset);
 
static ssize_t __c2port_show_dev_id(struct c2port_device *dev, char *buf)
{
<------>u8 data;
<------>int ret;
 
<------>/* Select DEVICEID register for C2 data register accesses */
<------>c2port_write_ar(dev, C2PORT_DEVICEID);
 
<------>/* Read and return the device ID register */
<------>ret = c2port_read_dr(dev, &data);
<------>if (ret < 0)
<------><------>return ret;
 
<------>return sprintf(buf, "%d\n", data);
}
 
static ssize_t c2port_show_dev_id(struct device *dev,
<------><------><------><------>struct device_attribute *attr, char *buf)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
<------>ssize_t ret;
 
<------>/* Check the device access status */
<------>if (!c2dev->access)
<------><------>return -EBUSY;
 
<------>mutex_lock(&c2dev->mutex);
<------>ret = __c2port_show_dev_id(c2dev, buf);
<------>mutex_unlock(&c2dev->mutex);
 
<------>if (ret < 0)
<------><------>dev_err(dev, "cannot read from %s\n", c2dev->name);
 
<------>return ret;
}
static DEVICE_ATTR(dev_id, 0444, c2port_show_dev_id, NULL);
 
static ssize_t __c2port_show_rev_id(struct c2port_device *dev, char *buf)
{
<------>u8 data;
<------>int ret;
 
<------>/* Select REVID register for C2 data register accesses */
<------>c2port_write_ar(dev, C2PORT_REVID);
 
<------>/* Read and return the revision ID register */
<------>ret = c2port_read_dr(dev, &data);
<------>if (ret < 0)
<------><------>return ret;
 
<------>return sprintf(buf, "%d\n", data);
}
 
static ssize_t c2port_show_rev_id(struct device *dev,
<------><------><------><------>struct device_attribute *attr, char *buf)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
<------>ssize_t ret;
 
<------>/* Check the device access status */
<------>if (!c2dev->access)
<------><------>return -EBUSY;
 
<------>mutex_lock(&c2dev->mutex);
<------>ret = __c2port_show_rev_id(c2dev, buf);
<------>mutex_unlock(&c2dev->mutex);
 
<------>if (ret < 0)
<------><------>dev_err(c2dev->dev, "cannot read from %s\n", c2dev->name);
 
<------>return ret;
}
static DEVICE_ATTR(rev_id, 0444, c2port_show_rev_id, NULL);
 
static ssize_t c2port_show_flash_access(struct device *dev,
<------><------><------><------>struct device_attribute *attr, char *buf)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
 
<------>return sprintf(buf, "%d\n", c2dev->flash_access);
}
 
static ssize_t __c2port_store_flash_access(struct c2port_device *dev,
<------><------><------><------><------><------>int status)
{
<------>int ret;
 
<------>/* Check the device access status */
<------>if (!dev->access)
<------><------>return -EBUSY;
 
<------>dev->flash_access = !!status;
 
<------>/* If flash_access is off we have nothing to do... */
<------>if (dev->flash_access == 0)
<------><------>return 0;
 
<------>/* Target the C2 flash programming control register for C2 data
<------> * register access */
<------>c2port_write_ar(dev, C2PORT_FPCTL);
 
<------>/* Write the first keycode to enable C2 Flash programming */
<------>ret = c2port_write_dr(dev, 0x02);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Write the second keycode to enable C2 Flash programming */
<------>ret = c2port_write_dr(dev, 0x01);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Delay for at least 20ms to ensure the target is ready for
<------> * C2 flash programming */
<------>mdelay(25);
 
<------>return 0;
}
 
static ssize_t c2port_store_flash_access(struct device *dev,
<------><------><------><------>struct device_attribute *attr,
<------><------><------><------>const char *buf, size_t count)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
<------>int status;
<------>ssize_t ret;
 
<------>ret = sscanf(buf, "%d", &status);
<------>if (ret != 1)
<------><------>return -EINVAL;
 
<------>mutex_lock(&c2dev->mutex);
<------>ret = __c2port_store_flash_access(c2dev, status);
<------>mutex_unlock(&c2dev->mutex);
 
<------>if (ret < 0) {
<------><------>dev_err(c2dev->dev, "cannot enable %s flash programming\n",
<------><------><------>c2dev->name);
<------><------>return ret;
<------>}
 
<------>return count;
}
static DEVICE_ATTR(flash_access, 0644, c2port_show_flash_access,
<------><------>   c2port_store_flash_access);
 
static ssize_t __c2port_write_flash_erase(struct c2port_device *dev)
{
<------>u8 status;
<------>int ret;
 
<------>/* Target the C2 flash programming data register for C2 data register
<------> * access.
<------> */
<------>c2port_write_ar(dev, C2PORT_FPDAT);
 
<------>/* Send device erase command */
<------>c2port_write_dr(dev, C2PORT_DEVICE_ERASE);
 
<------>/* Wait for input acknowledge */
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Should check status before starting FLASH access sequence */
 
<------>/* Wait for status information */
<------>ret = c2port_poll_out_ready(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Read flash programming interface status */
<------>ret = c2port_read_dr(dev, &status);
<------>if (ret < 0)
<------><------>return ret;
<------>if (status != C2PORT_COMMAND_OK)
<------><------>return -EBUSY;
 
<------>/* Send a three-byte arming sequence to enable the device erase.
<------> * If the sequence is not received correctly, the command will be
<------> * ignored.
<------> * Sequence is: 0xde, 0xad, 0xa5.
<------> */
<------>c2port_write_dr(dev, 0xde);
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
<------>c2port_write_dr(dev, 0xad);
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
<------>c2port_write_dr(dev, 0xa5);
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>ret = c2port_poll_out_ready(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>return 0;
}
 
static ssize_t c2port_store_flash_erase(struct device *dev,
<------><------><------><------>struct device_attribute *attr,
<------><------><------><------>const char *buf, size_t count)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(dev);
<------>int ret;
 
<------>/* Check the device and flash access status */
<------>if (!c2dev->access || !c2dev->flash_access)
<------><------>return -EBUSY;
 
<------>mutex_lock(&c2dev->mutex);
<------>ret = __c2port_write_flash_erase(c2dev);
<------>mutex_unlock(&c2dev->mutex);
 
<------>if (ret < 0) {
<------><------>dev_err(c2dev->dev, "cannot erase %s flash\n", c2dev->name);
<------><------>return ret;
<------>}
 
<------>return count;
}
static DEVICE_ATTR(flash_erase, 0200, NULL, c2port_store_flash_erase);
 
static ssize_t __c2port_read_flash_data(struct c2port_device *dev,
<------><------><------><------>char *buffer, loff_t offset, size_t count)
{
<------>struct c2port_ops *ops = dev->ops;
<------>u8 status, nread = 128;
<------>int i, ret;
 
<------>/* Check for flash end */
<------>if (offset >= ops->block_size * ops->blocks_num)
<------><------>return 0;
 
<------>if (ops->block_size * ops->blocks_num - offset < nread)
<------><------>nread = ops->block_size * ops->blocks_num - offset;
<------>if (count < nread)
<------><------>nread = count;
<------>if (nread == 0)
<------><------>return nread;
 
<------>/* Target the C2 flash programming data register for C2 data register
<------> * access */
<------>c2port_write_ar(dev, C2PORT_FPDAT);
 
<------>/* Send flash block read command */
<------>c2port_write_dr(dev, C2PORT_BLOCK_READ);
 
<------>/* Wait for input acknowledge */
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Should check status before starting FLASH access sequence */
 
<------>/* Wait for status information */
<------>ret = c2port_poll_out_ready(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Read flash programming interface status */
<------>ret = c2port_read_dr(dev, &status);
<------>if (ret < 0)
<------><------>return ret;
<------>if (status != C2PORT_COMMAND_OK)
<------><------>return -EBUSY;
 
<------>/* Send address high byte */
<------>c2port_write_dr(dev, offset >> 8);
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Send address low byte */
<------>c2port_write_dr(dev, offset & 0x00ff);
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Send address block size */
<------>c2port_write_dr(dev, nread);
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Should check status before reading FLASH block */
 
<------>/* Wait for status information */
<------>ret = c2port_poll_out_ready(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Read flash programming interface status */
<------>ret = c2port_read_dr(dev, &status);
<------>if (ret < 0)
<------><------>return ret;
<------>if (status != C2PORT_COMMAND_OK)
<------><------>return -EBUSY;
 
<------>/* Read flash block */
<------>for (i = 0; i < nread; i++) {
<------><------>ret = c2port_poll_out_ready(dev);
<------><------>if (ret < 0)
<------><------><------>return ret;
 
<------><------>ret = c2port_read_dr(dev, buffer+i);
<------><------>if (ret < 0)
<------><------><------>return ret;
<------>}
 
<------>return nread;
}
 
static ssize_t c2port_read_flash_data(struct file *filp, struct kobject *kobj,
<------><------><------><------>struct bin_attribute *attr,
<------><------><------><------>char *buffer, loff_t offset, size_t count)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(kobj_to_dev(kobj));
<------>ssize_t ret;
 
<------>/* Check the device and flash access status */
<------>if (!c2dev->access || !c2dev->flash_access)
<------><------>return -EBUSY;
 
<------>mutex_lock(&c2dev->mutex);
<------>ret = __c2port_read_flash_data(c2dev, buffer, offset, count);
<------>mutex_unlock(&c2dev->mutex);
 
<------>if (ret < 0)
<------><------>dev_err(c2dev->dev, "cannot read %s flash\n", c2dev->name);
 
<------>return ret;
}
 
static ssize_t __c2port_write_flash_data(struct c2port_device *dev,
<------><------><------><------>char *buffer, loff_t offset, size_t count)
{
<------>struct c2port_ops *ops = dev->ops;
<------>u8 status, nwrite = 128;
<------>int i, ret;
 
<------>if (nwrite > count)
<------><------>nwrite = count;
<------>if (ops->block_size * ops->blocks_num - offset < nwrite)
<------><------>nwrite = ops->block_size * ops->blocks_num - offset;
 
<------>/* Check for flash end */
<------>if (offset >= ops->block_size * ops->blocks_num)
<------><------>return -EINVAL;
 
<------>/* Target the C2 flash programming data register for C2 data register
<------> * access */
<------>c2port_write_ar(dev, C2PORT_FPDAT);
 
<------>/* Send flash block write command */
<------>c2port_write_dr(dev, C2PORT_BLOCK_WRITE);
 
<------>/* Wait for input acknowledge */
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Should check status before starting FLASH access sequence */
 
<------>/* Wait for status information */
<------>ret = c2port_poll_out_ready(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Read flash programming interface status */
<------>ret = c2port_read_dr(dev, &status);
<------>if (ret < 0)
<------><------>return ret;
<------>if (status != C2PORT_COMMAND_OK)
<------><------>return -EBUSY;
 
<------>/* Send address high byte */
<------>c2port_write_dr(dev, offset >> 8);
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Send address low byte */
<------>c2port_write_dr(dev, offset & 0x00ff);
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Send address block size */
<------>c2port_write_dr(dev, nwrite);
<------>ret = c2port_poll_in_busy(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Should check status before writing FLASH block */
 
<------>/* Wait for status information */
<------>ret = c2port_poll_out_ready(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>/* Read flash programming interface status */
<------>ret = c2port_read_dr(dev, &status);
<------>if (ret < 0)
<------><------>return ret;
<------>if (status != C2PORT_COMMAND_OK)
<------><------>return -EBUSY;
 
<------>/* Write flash block */
<------>for (i = 0; i < nwrite; i++) {
<------><------>ret = c2port_write_dr(dev, *(buffer+i));
<------><------>if (ret < 0)
<------><------><------>return ret;
 
<------><------>ret = c2port_poll_in_busy(dev);
<------><------>if (ret < 0)
<------><------><------>return ret;
 
<------>}
 
<------>/* Wait for last flash write to complete */
<------>ret = c2port_poll_out_ready(dev);
<------>if (ret < 0)
<------><------>return ret;
 
<------>return nwrite;
}
 
static ssize_t c2port_write_flash_data(struct file *filp, struct kobject *kobj,
<------><------><------><------>struct bin_attribute *attr,
<------><------><------><------>char *buffer, loff_t offset, size_t count)
{
<------>struct c2port_device *c2dev = dev_get_drvdata(kobj_to_dev(kobj));
<------>int ret;
 
<------>/* Check the device access status */
<------>if (!c2dev->access || !c2dev->flash_access)
<------><------>return -EBUSY;
 
<------>mutex_lock(&c2dev->mutex);
<------>ret = __c2port_write_flash_data(c2dev, buffer, offset, count);
<------>mutex_unlock(&c2dev->mutex);
 
<------>if (ret < 0)
<------><------>dev_err(c2dev->dev, "cannot write %s flash\n", c2dev->name);
 
<------>return ret;
}
/* size is computed at run-time */
static BIN_ATTR(flash_data, 0644, c2port_read_flash_data,
<------><------>c2port_write_flash_data, 0);
 
/*
 * Class attributes
 */
static struct attribute *c2port_attrs[] = {
<------>&dev_attr_name.attr,
<------>&dev_attr_flash_blocks_num.attr,
<------>&dev_attr_flash_block_size.attr,
<------>&dev_attr_flash_size.attr,
<------>&dev_attr_access.attr,
<------>&dev_attr_reset.attr,
<------>&dev_attr_dev_id.attr,
<------>&dev_attr_rev_id.attr,
<------>&dev_attr_flash_access.attr,
<------>&dev_attr_flash_erase.attr,
<------>NULL,
};
 
static struct bin_attribute *c2port_bin_attrs[] = {
<------>&bin_attr_flash_data,
<------>NULL,
};
 
static const struct attribute_group c2port_group = {
<------>.attrs = c2port_attrs,
<------>.bin_attrs = c2port_bin_attrs,
};
 
static const struct attribute_group *c2port_groups[] = {
<------>&c2port_group,
<------>NULL,
};
 
/*
 * Exported functions
 */
 
struct c2port_device *c2port_device_register(char *name,
<------><------><------><------><------>struct c2port_ops *ops, void *devdata)
{
<------>struct c2port_device *c2dev;
<------>int ret;
 
<------>if (unlikely(!ops) || unlikely(!ops->access) || \
<------><------>unlikely(!ops->c2d_dir) || unlikely(!ops->c2ck_set) || \
<------><------>unlikely(!ops->c2d_get) || unlikely(!ops->c2d_set))
<------><------>return ERR_PTR(-EINVAL);
 
<------>c2dev = kmalloc(sizeof(struct c2port_device), GFP_KERNEL);
<------>if (unlikely(!c2dev))
<------><------>return ERR_PTR(-ENOMEM);
 
<------>idr_preload(GFP_KERNEL);
<------>spin_lock_irq(&c2port_idr_lock);
<------>ret = idr_alloc(&c2port_idr, c2dev, 0, 0, GFP_NOWAIT);
<------>spin_unlock_irq(&c2port_idr_lock);
<------>idr_preload_end();
 
<------>if (ret < 0)
<------><------>goto error_idr_alloc;
<------>c2dev->id = ret;
 
<------>bin_attr_flash_data.size = ops->blocks_num * ops->block_size;
 
<------>c2dev->dev = device_create(c2port_class, NULL, 0, c2dev,
<------><------><------><------>   "c2port%d", c2dev->id);
<------>if (IS_ERR(c2dev->dev)) {
<------><------>ret = PTR_ERR(c2dev->dev);
<------><------>goto error_device_create;
<------>}
<------>dev_set_drvdata(c2dev->dev, c2dev);
 
<------>strncpy(c2dev->name, name, C2PORT_NAME_LEN - 1);
<------>c2dev->ops = ops;
<------>mutex_init(&c2dev->mutex);
 
<------>/* By default C2 port access is off */
<------>c2dev->access = c2dev->flash_access = 0;
<------>ops->access(c2dev, 0);
 
<------>dev_info(c2dev->dev, "C2 port %s added\n", name);
<------>dev_info(c2dev->dev, "%s flash has %d blocks x %d bytes "
<------><------><------><------>"(%d bytes total)\n",
<------><------><------><------>name, ops->blocks_num, ops->block_size,
<------><------><------><------>ops->blocks_num * ops->block_size);
 
<------>return c2dev;
 
error_device_create:
<------>spin_lock_irq(&c2port_idr_lock);
<------>idr_remove(&c2port_idr, c2dev->id);
<------>spin_unlock_irq(&c2port_idr_lock);
 
error_idr_alloc:
<------>kfree(c2dev);
 
<------>return ERR_PTR(ret);
}
EXPORT_SYMBOL(c2port_device_register);
 
void c2port_device_unregister(struct c2port_device *c2dev)
{
<------>if (!c2dev)
<------><------>return;
 
<------>dev_info(c2dev->dev, "C2 port %s removed\n", c2dev->name);
 
<------>spin_lock_irq(&c2port_idr_lock);
<------>idr_remove(&c2port_idr, c2dev->id);
<------>spin_unlock_irq(&c2port_idr_lock);
 
<------>device_destroy(c2port_class, c2dev->id);
 
<------>kfree(c2dev);
}
EXPORT_SYMBOL(c2port_device_unregister);
 
/*
 * Module stuff
 */
 
static int __init c2port_init(void)
{
<------>printk(KERN_INFO "Silicon Labs C2 port support v. " DRIVER_VERSION
<------><------>" - (C) 2007 Rodolfo Giometti\n");
 
<------>c2port_class = class_create(THIS_MODULE, "c2port");
<------>if (IS_ERR(c2port_class)) {
<------><------>printk(KERN_ERR "c2port: failed to allocate class\n");
<------><------>return PTR_ERR(c2port_class);
<------>}
<------>c2port_class->dev_groups = c2port_groups;
 
<------>return 0;
}
 
static void __exit c2port_exit(void)
{
<------>class_destroy(c2port_class);
}
 
module_init(c2port_init);
module_exit(c2port_exit);
 
MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
MODULE_DESCRIPTION("Silicon Labs C2 port support v. " DRIVER_VERSION);
MODULE_LICENSE("GPL");