linux/drivers/media/pci/solo6x10/solo6x10-eeprom.c

151 lines
3.8 KiB
C

/*
* Copyright (C) 2010-2013 Bluecherry, LLC <http://www.bluecherrydvr.com>
*
* Original author:
* Ben Collins <bcollins@ubuntu.com>
*
* Additional work by:
* John Brooks <john.brooks@bluecherry.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that 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/kernel.h>
#include <linux/delay.h>
#include "solo6x10.h"
/* Control */
#define EE_SHIFT_CLK 0x04
#define EE_CS 0x08
#define EE_DATA_WRITE 0x02
#define EE_DATA_READ 0x01
#define EE_ENB (0x80 | EE_CS)
#define eeprom_delay() udelay(100)
#if 0
#define eeprom_delay() solo_reg_read(solo_dev, SOLO_EEPROM_CTRL)
#define eeprom_delay() ({ \
int i, ret; \
udelay(100); \
for (i = ret = 0; i < 1000 && !ret; i++) \
ret = solo_eeprom_reg_read(solo_dev); \
})
#endif
#define ADDR_LEN 6
/* Commands */
#define EE_EWEN_CMD 4
#define EE_EWDS_CMD 4
#define EE_WRITE_CMD 5
#define EE_READ_CMD 6
#define EE_ERASE_CMD 7
static unsigned int solo_eeprom_reg_read(struct solo_dev *solo_dev)
{
return solo_reg_read(solo_dev, SOLO_EEPROM_CTRL) & EE_DATA_READ;
}
static void solo_eeprom_reg_write(struct solo_dev *solo_dev, u32 data)
{
solo_reg_write(solo_dev, SOLO_EEPROM_CTRL, data);
eeprom_delay();
}
static void solo_eeprom_cmd(struct solo_dev *solo_dev, int cmd)
{
int i;
solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ACCESS_EN);
solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE);
for (i = 4 + ADDR_LEN; i >= 0; i--) {
int dataval = (cmd & (1 << i)) ? EE_DATA_WRITE : 0;
solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE | dataval);
solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE |
EE_SHIFT_CLK | dataval);
}
solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE);
}
unsigned int solo_eeprom_ewen(struct solo_dev *solo_dev, int w_en)
{
int ewen_cmd = (w_en ? 0x3f : 0) | (EE_EWEN_CMD << ADDR_LEN);
unsigned int retval = 0;
int i;
solo_eeprom_cmd(solo_dev, ewen_cmd);
for (i = 0; i < 16; i++) {
solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE |
EE_SHIFT_CLK);
retval = (retval << 1) | solo_eeprom_reg_read(solo_dev);
solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE);
retval = (retval << 1) | solo_eeprom_reg_read(solo_dev);
}
solo_eeprom_reg_write(solo_dev, ~EE_CS);
retval = (retval << 1) | solo_eeprom_reg_read(solo_dev);
return retval;
}
__be16 solo_eeprom_read(struct solo_dev *solo_dev, int loc)
{
int read_cmd = loc | (EE_READ_CMD << ADDR_LEN);
u16 retval = 0;
int i;
solo_eeprom_cmd(solo_dev, read_cmd);
for (i = 0; i < 16; i++) {
solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE |
EE_SHIFT_CLK);
retval = (retval << 1) | solo_eeprom_reg_read(solo_dev);
solo_eeprom_reg_write(solo_dev, SOLO_EEPROM_ENABLE);
}
solo_eeprom_reg_write(solo_dev, ~EE_CS);
return (__force __be16)retval;
}
int solo_eeprom_write(struct solo_dev *solo_dev, int loc,
__be16 data)
{
int write_cmd = loc | (EE_WRITE_CMD << ADDR_LEN);
unsigned int retval;
int i;
solo_eeprom_cmd(solo_dev, write_cmd);
for (i = 15; i >= 0; i--) {
unsigned int dataval = ((__force unsigned)data >> i) & 1;
solo_eeprom_reg_write(solo_dev, EE_ENB);
solo_eeprom_reg_write(solo_dev,
EE_ENB | (dataval << 1) | EE_SHIFT_CLK);
}
solo_eeprom_reg_write(solo_dev, EE_ENB);
solo_eeprom_reg_write(solo_dev, ~EE_CS);
solo_eeprom_reg_write(solo_dev, EE_ENB);
for (i = retval = 0; i < 10000 && !retval; i++)
retval = solo_eeprom_reg_read(solo_dev);
solo_eeprom_reg_write(solo_dev, ~EE_CS);
return !retval;
}