freebsd-skq/sys/mips/rmi/xlr_i2c.c
jchandra d381cdd7a8 I2C drivers for XLR/XLS processors.
- Major update to xlr_i2c.c: do multi-byte ops correctly, remove unnecessary
  code, add mutex to protect bus operations, style(9) fixes.
- Drivers for I2C devices on XLR/XLS engineering boards, ds1374u RTC, max6657
  temparature sensor and at24co2n EEPROM.

Submitted by:	Sreekanth M. S. (kanthms at netlogicmicro com)
2010-12-12 06:00:26 +00:00

407 lines
10 KiB
C

/*-
* Copyright (c) 2003-2009 RMI Corporation
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of RMI Corporation, nor the names of its contributors,
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* RMI_BSD */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* I2C driver for the Palm-BK3220 I2C Host adapter on the RMI XLR.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/bus.h>
#include <sys/rman.h>
#include <dev/iicbus/iiconf.h>
#include <dev/iicbus/iicbus.h>
#include <mips/rmi/board.h>
#include <mips/rmi/iomap.h>
#include <mips/include/resource.h>
#include "iicbus_if.h"
/* XLR I2C REGISTERS */
#define XLR_I2C_CFG 0x00
#define XLR_I2C_CLKDIV 0x01
#define XLR_I2C_DEVADDR 0x02
#define XLR_I2C_ADDR 0x03
#define XLR_I2C_DATAOUT 0x04
#define XLR_I2C_DATAIN 0x05
#define XLR_I2C_STATUS 0x06
#define XLR_I2C_STARTXFR 0x07
#define XLR_I2C_BYTECNT 0x08
#define XLR_I2C_HDSTATIM 0x09
/* XLR I2C REGISTERS FLAGS */
#define XLR_I2C_BUS_BUSY 0x01
#define XLR_I2C_SDOEMPTY 0x02
#define XLR_I2C_RXRDY 0x04
#define XLR_I2C_ACK_ERR 0x08
#define XLR_I2C_ARB_STARTERR 0x30
/* Register Programming Values!! Change as required */
#define XLR_I2C_CFG_ADDR 0xF8 /* 8-Bit dev Addr + POR Values */
#define XLR_I2C_CFG_NOADDR 0xFA /* 8-Bit reg Addr + POR Values : No dev addr */
#define XLR_I2C_STARTXFR_ND 0x02 /* No data , only addr */
#define XLR_I2C_STARTXFR_RD 0x01 /* Read */
#define XLR_I2C_STARTXFR_WR 0x00 /* Write */
#define XLR_I2C_CLKDIV_DEF 0x14A /* 0x00000052 */
#define XLR_I2C_HDSTATIM_DEF 0x107 /* 0x00000000 */
#define MAXTIME 0x10000
#define ARIZONA_I2C_BUS 1
static devclass_t xlr_i2c_devclass;
/*
* Device methods
*/
static int xlr_i2c_probe(device_t);
static int xlr_i2c_attach(device_t);
static int xlr_i2c_detach(device_t);
static int xlr_i2c_start(device_t dev, u_char slave, int timeout);
static int xlr_i2c_stop(device_t dev);
static int xlr_i2c_read(device_t dev, char *buf, int len, int *read, int last, int delay);
static int xlr_i2c_write(device_t dev, const char *buf, int len, int *sent, int timeout);
static int xlr_i2c_callback(device_t dev, int index, caddr_t data);
static int xlr_i2c_repeated_start(device_t dev, u_char slave, int timeout);
static int xlr_i2c_transfer(device_t bus, struct iic_msg *msgs, uint32_t nmsgs);
struct xlr_i2c_softc {
device_t dev; /* Self */
struct resource *mem_res; /* Memory resource */
volatile int flags;
int sc_started;
uint8_t i2cdev_addr;
xlr_reg_t *iobase_i2c_regs;
device_t iicbus;
struct mtx sc_mtx;
};
static void
set_i2c_base(device_t dev)
{
struct xlr_i2c_softc *sc;
sc = device_get_softc(dev);
if (device_get_unit(dev) == 0)
sc->iobase_i2c_regs = xlr_io_mmio(XLR_IO_I2C_0_OFFSET);
else
sc->iobase_i2c_regs = xlr_io_mmio(XLR_IO_I2C_1_OFFSET);
}
static void
xlr_i2c_dev_write(device_t dev, int reg, int value)
{
struct xlr_i2c_softc *sc;
sc = device_get_softc(dev);
xlr_write_reg(sc->iobase_i2c_regs, reg, value);
return;
}
static int
xlr_i2c_dev_read(device_t dev, int reg)
{
uint32_t val;
struct xlr_i2c_softc *sc;
sc = device_get_softc(dev);
val = xlr_read_reg(sc->iobase_i2c_regs, reg);
return ((int)val);
}
static int
xlr_i2c_probe(device_t dev)
{
device_set_desc(dev, "XLR/XLS I2C bus controller");
return (0);
}
/*
* We add all the devices which we know about.
* The generic attach routine will attach them if they are alive.
*/
static int
xlr_i2c_attach(device_t dev)
{
int rid;
struct xlr_i2c_softc *sc;
device_t tmpd;
if(device_get_unit(dev)!=ARIZONA_I2C_BUS) {
device_printf(dev, "unused iicbus instance\n");
return 0;
}
sc = device_get_softc(dev);
set_i2c_base(dev);
mtx_init(&sc->sc_mtx, "xlr_i2c", "xlr_i2c", MTX_DEF);
sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid, RF_ACTIVE);
if (sc->mem_res == NULL) {
printf("not able to allocate the bus resource\n");
}
if ((sc->iicbus = device_add_child(dev, "iicbus", -1)) == NULL) {
printf("could not allocate iicbus instance\n");
return -1;
}
if(xlr_board_info.xlr_i2c_device[I2C_RTC].enabled == 1) {
tmpd = device_add_child(sc->iicbus, "ds1374u", 0);
device_set_ivars(tmpd, &xlr_board_info.xlr_i2c_device[I2C_RTC]);
}
if(xlr_board_info.xlr_i2c_device[I2C_THERMAL].enabled == 1) {
tmpd = device_add_child(sc->iicbus, "max6657", 0);
device_set_ivars(tmpd, &xlr_board_info.xlr_i2c_device[I2C_THERMAL]);
}
if(xlr_board_info.xlr_i2c_device[I2C_EEPROM].enabled == 1) {
tmpd = device_add_child(sc->iicbus, "at24co2n", 0);
device_set_ivars(tmpd, &xlr_board_info.xlr_i2c_device[I2C_EEPROM]);
}
bus_generic_attach(dev);
return (0);
}
static int
xlr_i2c_detach(device_t dev)
{
bus_generic_detach(dev);
return (0);
}
static int
xlr_i2c_start(device_t dev, u_char slave, int timeout)
{
int error = 0;
struct xlr_i2c_softc *sc;
sc = device_get_softc(dev);
mtx_lock(&sc->sc_mtx);
sc->sc_started = 1;
sc->i2cdev_addr = (slave >> 1);
return error;
}
static int
xlr_i2c_stop(device_t dev)
{
int error = 0;
struct xlr_i2c_softc *sc;
sc = device_get_softc(dev);
mtx_unlock(&sc->sc_mtx);
return error;
}
static int
xlr_i2c_read(device_t dev, char *buf, int len, int *read, int last,
int delay)
{
volatile uint32_t i2c_status = 0;
int pos=0;
int timeout = 0;
xlr_i2c_dev_write(dev, XLR_I2C_CFG, XLR_I2C_CFG_NOADDR);
xlr_i2c_dev_write(dev, XLR_I2C_BYTECNT, len);
retry:
xlr_i2c_dev_write(dev, XLR_I2C_STARTXFR, XLR_I2C_STARTXFR_RD);
timeout = 0;
while(1) {
if(timeout++ > MAXTIME)
return -1;
i2c_status = xlr_i2c_dev_read(dev, XLR_I2C_STATUS);
if (i2c_status & XLR_I2C_RXRDY)
buf[pos++] = (uint8_t) xlr_i2c_dev_read(dev, XLR_I2C_DATAIN);
/* ACKERR -- bail */
if (i2c_status & XLR_I2C_ACK_ERR)
return -1; /* ACK_ERROR */
/* LOST ARB or STARTERR -- repeat */
if (i2c_status & XLR_I2C_ARB_STARTERR)
goto retry;
/* Wait for busy bit to go away */
if (i2c_status & XLR_I2C_BUS_BUSY)
continue;
if (pos == len)
break;
}
*read = pos;
return 0;
}
static int
xlr_i2c_write(device_t dev, const char *buf, int len, int *sent, int timeout /* us */ )
{
volatile uint32_t i2c_status = 0x00;
uint8_t devaddr, addr;
struct xlr_i2c_softc *sc;
int pos;
sc = device_get_softc(dev);
/* the first byte of write is addr (of register in device) */
addr = buf[0];
devaddr = sc->i2cdev_addr;
xlr_i2c_dev_write(dev, XLR_I2C_ADDR, addr);
xlr_i2c_dev_write(dev, XLR_I2C_DEVADDR, devaddr);
xlr_i2c_dev_write(dev, XLR_I2C_CFG, XLR_I2C_CFG_ADDR);
xlr_i2c_dev_write(dev, XLR_I2C_BYTECNT, len - 1);
retry:
pos = 1;
if (len == 1) /* there is no data only address */
xlr_i2c_dev_write(dev, XLR_I2C_STARTXFR, XLR_I2C_STARTXFR_ND);
else {
xlr_i2c_dev_write(dev, XLR_I2C_STARTXFR, XLR_I2C_STARTXFR_WR);
xlr_i2c_dev_write(dev, XLR_I2C_DATAOUT, buf[pos]);
}
while (1) {
i2c_status = xlr_i2c_dev_read(dev, XLR_I2C_STATUS);
/* sdo empty send next byte */
if (i2c_status & XLR_I2C_SDOEMPTY) {
pos++;
xlr_i2c_dev_write(dev, XLR_I2C_DATAOUT, buf[pos]);
}
/* LOST ARB or STARTERR -- repeat */
if (i2c_status & XLR_I2C_ARB_STARTERR)
goto retry;
/* ACKERR -- bail */
if (i2c_status & XLR_I2C_ACK_ERR) {
printf("ACK ERR : exiting\n ");
return -1;
}
/* busy try again */
if (i2c_status & XLR_I2C_BUS_BUSY)
continue;
if (pos >= len)
break;;
}
*sent = len - 1;
return 0;
}
static int
xlr_i2c_callback(device_t dev, int index, caddr_t data)
{
return 0;
}
static int
xlr_i2c_repeated_start(device_t dev, u_char slave, int timeout)
{
return 0;
}
/*
* I2C bus transfer for RMI boards and devices.
* Generic version of iicbus_transfer that calls the appropriate
* routines to accomplish this. See note above about acceptable
* buffer addresses.
*/
int
xlr_i2c_transfer(device_t bus, struct iic_msg *msgs, uint32_t nmsgs)
{
int i, error, lenread, lenwrote;
u_char addr;
addr = msgs[0].slave | LSB;
error = xlr_i2c_start(bus, addr, 0);
for (i = 0, error = 0; i < nmsgs && error == 0; i++) {
if (msgs[i].flags & IIC_M_RD) {
error = xlr_i2c_read((bus), msgs[i].buf, msgs[i].len, &lenread, IIC_LAST_READ, 0);
}
else {
error = xlr_i2c_write((bus), msgs[i].buf, msgs[i].len, &lenwrote, 0);
}
}
error = xlr_i2c_stop(bus);
return (error);
}
static device_method_t xlr_i2c_methods[] = {
/* device interface */
DEVMETHOD(device_probe, xlr_i2c_probe),
DEVMETHOD(device_attach, xlr_i2c_attach),
DEVMETHOD(device_detach, xlr_i2c_detach),
/* iicbus interface */
DEVMETHOD(iicbus_callback, xlr_i2c_callback),
DEVMETHOD(iicbus_repeated_start, xlr_i2c_repeated_start),
DEVMETHOD(iicbus_start, xlr_i2c_start),
DEVMETHOD(iicbus_stop, xlr_i2c_stop),
DEVMETHOD(iicbus_write, xlr_i2c_write),
DEVMETHOD(iicbus_read, xlr_i2c_read),
DEVMETHOD(iicbus_transfer, xlr_i2c_transfer),
{0, 0}
};
static driver_t xlr_i2c_driver = {
"xlr_i2c",
xlr_i2c_methods,
sizeof(struct xlr_i2c_softc),
};
DRIVER_MODULE(xlr_i2c, iodi, xlr_i2c_driver, xlr_i2c_devclass, 0, 0);
DRIVER_MODULE(iicbus, xlr_i2c, iicbus_driver, iicbus_devclass, 0, 0);