diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 15:20:36 -0700 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/i2c/algos |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/i2c/algos')
-rw-r--r-- | drivers/i2c/algos/Kconfig | 70 | ||||
-rw-r--r-- | drivers/i2c/algos/Makefile | 14 | ||||
-rw-r--r-- | drivers/i2c/algos/i2c-algo-bit.c | 573 | ||||
-rw-r--r-- | drivers/i2c/algos/i2c-algo-ite.c | 812 | ||||
-rw-r--r-- | drivers/i2c/algos/i2c-algo-ite.h | 117 | ||||
-rw-r--r-- | drivers/i2c/algos/i2c-algo-pca.c | 399 | ||||
-rw-r--r-- | drivers/i2c/algos/i2c-algo-pca.h | 26 | ||||
-rw-r--r-- | drivers/i2c/algos/i2c-algo-pcf.c | 507 | ||||
-rw-r--r-- | drivers/i2c/algos/i2c-algo-pcf.h | 76 | ||||
-rw-r--r-- | drivers/i2c/algos/i2c-algo-sgi.c | 189 | ||||
-rw-r--r-- | drivers/i2c/algos/i2c-algo-sibyte.c | 222 |
11 files changed, 3005 insertions, 0 deletions
diff --git a/drivers/i2c/algos/Kconfig b/drivers/i2c/algos/Kconfig new file mode 100644 index 00000000000..30408015d23 --- /dev/null +++ b/drivers/i2c/algos/Kconfig @@ -0,0 +1,70 @@ +# +# Character device configuration +# + +menu "I2C Algorithms" + depends on I2C + +config I2C_ALGOBIT + tristate "I2C bit-banging interfaces" + depends on I2C + help + This allows you to use a range of I2C adapters called bit-banging + adapters. Say Y if you own an I2C adapter belonging to this class + and then say Y to the specific driver for you adapter below. + + This support is also available as a module. If so, the module + will be called i2c-algo-bit. + +config I2C_ALGOPCF + tristate "I2C PCF 8584 interfaces" + depends on I2C + help + This allows you to use a range of I2C adapters called PCF adapters. + Say Y if you own an I2C adapter belonging to this class and then say + Y to the specific driver for you adapter below. + + This support is also available as a module. If so, the module + will be called i2c-algo-pcf. + +config I2C_ALGOPCA + tristate "I2C PCA 9564 interfaces" + depends on I2C + help + This allows you to use a range of I2C adapters called PCA adapters. + Say Y if you own an I2C adapter belonging to this class and then say + Y to the specific driver for you adapter below. + + This support is also available as a module. If so, the module + will be called i2c-algo-pca. + +config I2C_ALGOITE + tristate "ITE I2C Algorithm" + depends on MIPS_ITE8172 && I2C + help + This supports the use of the ITE8172 I2C interface found on some MIPS + systems. Say Y if you have one of these. You should also say Y for + the ITE I2C peripheral driver support below. + + This support is also available as a module. If so, the module + will be called i2c-algo-ite. + +config I2C_ALGO8XX + tristate "MPC8xx CPM I2C interface" + depends on 8xx && I2C + +config I2C_ALGO_SIBYTE + tristate "SiByte SMBus interface" + depends on SIBYTE_SB1xxx_SOC && I2C + help + Supports the SiByte SOC on-chip I2C interfaces (2 channels). + +config I2C_ALGO_SGI + tristate "I2C SGI interfaces" + depends on I2C && (SGI_IP22 || SGI_IP32 || X86_VISWS) + help + Supports the SGI interfaces like the ones found on SGI Indy VINO + or SGI O2 MACE. + +endmenu + diff --git a/drivers/i2c/algos/Makefile b/drivers/i2c/algos/Makefile new file mode 100644 index 00000000000..867fe1f6740 --- /dev/null +++ b/drivers/i2c/algos/Makefile @@ -0,0 +1,14 @@ +# +# Makefile for the i2c algorithms +# + +obj-$(CONFIG_I2C_ALGOBIT) += i2c-algo-bit.o +obj-$(CONFIG_I2C_ALGOPCF) += i2c-algo-pcf.o +obj-$(CONFIG_I2C_ALGOPCA) += i2c-algo-pca.o +obj-$(CONFIG_I2C_ALGOITE) += i2c-algo-ite.o +obj-$(CONFIG_I2C_ALGO_SIBYTE) += i2c-algo-sibyte.o +obj-$(CONFIG_I2C_ALGO_SGI) += i2c-algo-sgi.o + +ifeq ($(CONFIG_I2C_DEBUG_ALGO),y) +EXTRA_CFLAGS += -DDEBUG +endif diff --git a/drivers/i2c/algos/i2c-algo-bit.c b/drivers/i2c/algos/i2c-algo-bit.c new file mode 100644 index 00000000000..fb5b732238e --- /dev/null +++ b/drivers/i2c/algos/i2c-algo-bit.c @@ -0,0 +1,573 @@ +/* ------------------------------------------------------------------------- */ +/* i2c-algo-bit.c i2c driver algorithms for bit-shift adapters */ +/* ------------------------------------------------------------------------- */ +/* Copyright (C) 1995-2000 Simon G. Vogl + + 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. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ +/* ------------------------------------------------------------------------- */ + +/* With some changes from Frodo Looijaard <frodol@dds.nl>, Kyösti Mälkki + <kmalkki@cc.hut.fi> and Jean Delvare <khali@linux-fr.org> */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/i2c.h> +#include <linux/i2c-algo-bit.h> + + +/* ----- global defines ----------------------------------------------- */ +#define DEB(x) if (i2c_debug>=1) x; +#define DEB2(x) if (i2c_debug>=2) x; +#define DEBSTAT(x) if (i2c_debug>=3) x; /* print several statistical values*/ +#define DEBPROTO(x) if (i2c_debug>=9) { x; } + /* debug the protocol by showing transferred bits */ + + +/* ----- global variables --------------------------------------------- */ + +/* module parameters: + */ +static int i2c_debug; +static int bit_test; /* see if the line-setting functions work */ + +/* --- setting states on the bus with the right timing: --------------- */ + +#define setsda(adap,val) adap->setsda(adap->data, val) +#define setscl(adap,val) adap->setscl(adap->data, val) +#define getsda(adap) adap->getsda(adap->data) +#define getscl(adap) adap->getscl(adap->data) + +static inline void sdalo(struct i2c_algo_bit_data *adap) +{ + setsda(adap,0); + udelay(adap->udelay); +} + +static inline void sdahi(struct i2c_algo_bit_data *adap) +{ + setsda(adap,1); + udelay(adap->udelay); +} + +static inline void scllo(struct i2c_algo_bit_data *adap) +{ + setscl(adap,0); + udelay(adap->udelay); +} + +/* + * Raise scl line, and do checking for delays. This is necessary for slower + * devices. + */ +static inline int sclhi(struct i2c_algo_bit_data *adap) +{ + unsigned long start; + + setscl(adap,1); + + /* Not all adapters have scl sense line... */ + if (adap->getscl == NULL ) { + udelay(adap->udelay); + return 0; + } + + start=jiffies; + while (! getscl(adap) ) { + /* the hw knows how to read the clock line, + * so we wait until it actually gets high. + * This is safer as some chips may hold it low + * while they are processing data internally. + */ + if (time_after_eq(jiffies, start+adap->timeout)) { + return -ETIMEDOUT; + } + cond_resched(); + } + DEBSTAT(printk(KERN_DEBUG "needed %ld jiffies\n", jiffies-start)); + udelay(adap->udelay); + return 0; +} + + +/* --- other auxiliary functions -------------------------------------- */ +static void i2c_start(struct i2c_algo_bit_data *adap) +{ + /* assert: scl, sda are high */ + DEBPROTO(printk("S ")); + sdalo(adap); + scllo(adap); +} + +static void i2c_repstart(struct i2c_algo_bit_data *adap) +{ + /* scl, sda may not be high */ + DEBPROTO(printk(" Sr ")); + setsda(adap,1); + sclhi(adap); + udelay(adap->udelay); + + sdalo(adap); + scllo(adap); +} + + +static void i2c_stop(struct i2c_algo_bit_data *adap) +{ + DEBPROTO(printk("P\n")); + /* assert: scl is low */ + sdalo(adap); + sclhi(adap); + sdahi(adap); +} + + + +/* send a byte without start cond., look for arbitration, + check ackn. from slave */ +/* returns: + * 1 if the device acknowledged + * 0 if the device did not ack + * -ETIMEDOUT if an error occurred (while raising the scl line) + */ +static int i2c_outb(struct i2c_adapter *i2c_adap, char c) +{ + int i; + int sb; + int ack; + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + + /* assert: scl is low */ + for ( i=7 ; i>=0 ; i-- ) { + sb = c & ( 1 << i ); + setsda(adap,sb); + udelay(adap->udelay); + DEBPROTO(printk(KERN_DEBUG "%d",sb!=0)); + if (sclhi(adap)<0) { /* timed out */ + sdahi(adap); /* we don't want to block the net */ + DEB2(printk(KERN_DEBUG " i2c_outb: 0x%02x, timeout at bit #%d\n", c&0xff, i)); + return -ETIMEDOUT; + }; + /* do arbitration here: + * if ( sb && ! getsda(adap) ) -> ouch! Get out of here. + */ + setscl(adap, 0 ); + udelay(adap->udelay); + } + sdahi(adap); + if (sclhi(adap)<0){ /* timeout */ + DEB2(printk(KERN_DEBUG " i2c_outb: 0x%02x, timeout at ack\n", c&0xff)); + return -ETIMEDOUT; + }; + /* read ack: SDA should be pulled down by slave */ + ack=getsda(adap); /* ack: sda is pulled low ->success. */ + DEB2(printk(KERN_DEBUG " i2c_outb: 0x%02x , getsda() = %d\n", c & 0xff, ack)); + + DEBPROTO( printk(KERN_DEBUG "[%2.2x]",c&0xff) ); + DEBPROTO(if (0==ack){ printk(KERN_DEBUG " A ");} else printk(KERN_DEBUG " NA ") ); + scllo(adap); + return 0==ack; /* return 1 if device acked */ + /* assert: scl is low (sda undef) */ +} + + +static int i2c_inb(struct i2c_adapter *i2c_adap) +{ + /* read byte via i2c port, without start/stop sequence */ + /* acknowledge is sent in i2c_read. */ + int i; + unsigned char indata=0; + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + + /* assert: scl is low */ + sdahi(adap); + for (i=0;i<8;i++) { + if (sclhi(adap)<0) { /* timeout */ + DEB2(printk(KERN_DEBUG " i2c_inb: timeout at bit #%d\n", 7-i)); + return -ETIMEDOUT; + }; + indata *= 2; + if ( getsda(adap) ) + indata |= 0x01; + scllo(adap); + } + /* assert: scl is low */ + DEB2(printk(KERN_DEBUG "i2c_inb: 0x%02x\n", indata & 0xff)); + + DEBPROTO(printk(KERN_DEBUG " 0x%02x", indata & 0xff)); + return (int) (indata & 0xff); +} + +/* + * Sanity check for the adapter hardware - check the reaction of + * the bus lines only if it seems to be idle. + */ +static int test_bus(struct i2c_algo_bit_data *adap, char* name) { + int scl,sda; + + if (adap->getscl==NULL) + printk(KERN_INFO "i2c-algo-bit.o: Testing SDA only, " + "SCL is not readable.\n"); + + sda=getsda(adap); + scl=(adap->getscl==NULL?1:getscl(adap)); + printk(KERN_DEBUG "i2c-algo-bit.o: (0) scl=%d, sda=%d\n",scl,sda); + if (!scl || !sda ) { + printk(KERN_WARNING "i2c-algo-bit.o: %s seems to be busy.\n", name); + goto bailout; + } + + sdalo(adap); + sda=getsda(adap); + scl=(adap->getscl==NULL?1:getscl(adap)); + printk(KERN_DEBUG "i2c-algo-bit.o: (1) scl=%d, sda=%d\n",scl,sda); + if ( 0 != sda ) { + printk(KERN_WARNING "i2c-algo-bit.o: SDA stuck high!\n"); + goto bailout; + } + if ( 0 == scl ) { + printk(KERN_WARNING "i2c-algo-bit.o: SCL unexpected low " + "while pulling SDA low!\n"); + goto bailout; + } + + sdahi(adap); + sda=getsda(adap); + scl=(adap->getscl==NULL?1:getscl(adap)); + printk(KERN_DEBUG "i2c-algo-bit.o: (2) scl=%d, sda=%d\n",scl,sda); + if ( 0 == sda ) { + printk(KERN_WARNING "i2c-algo-bit.o: SDA stuck low!\n"); + goto bailout; + } + if ( 0 == scl ) { + printk(KERN_WARNING "i2c-algo-bit.o: SCL unexpected low " + "while pulling SDA high!\n"); + goto bailout; + } + + scllo(adap); + sda=getsda(adap); + scl=(adap->getscl==NULL?0:getscl(adap)); + printk(KERN_DEBUG "i2c-algo-bit.o: (3) scl=%d, sda=%d\n",scl,sda); + if ( 0 != scl ) { + printk(KERN_WARNING "i2c-algo-bit.o: SCL stuck high!\n"); + goto bailout; + } + if ( 0 == sda ) { + printk(KERN_WARNING "i2c-algo-bit.o: SDA unexpected low " + "while pulling SCL low!\n"); + goto bailout; + } + + sclhi(adap); + sda=getsda(adap); + scl=(adap->getscl==NULL?1:getscl(adap)); + printk(KERN_DEBUG "i2c-algo-bit.o: (4) scl=%d, sda=%d\n",scl,sda); + if ( 0 == scl ) { + printk(KERN_WARNING "i2c-algo-bit.o: SCL stuck low!\n"); + goto bailout; + } + if ( 0 == sda ) { + printk(KERN_WARNING "i2c-algo-bit.o: SDA unexpected low " + "while pulling SCL high!\n"); + goto bailout; + } + printk(KERN_INFO "i2c-algo-bit.o: %s passed test.\n",name); + return 0; +bailout: + sdahi(adap); + sclhi(adap); + return -ENODEV; +} + +/* ----- Utility functions + */ + +/* try_address tries to contact a chip for a number of + * times before it gives up. + * return values: + * 1 chip answered + * 0 chip did not answer + * -x transmission error + */ +static inline int try_address(struct i2c_adapter *i2c_adap, + unsigned char addr, int retries) +{ + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + int i,ret = -1; + for (i=0;i<=retries;i++) { + ret = i2c_outb(i2c_adap,addr); + if (ret==1) + break; /* success! */ + i2c_stop(adap); + udelay(5/*adap->udelay*/); + if (i==retries) /* no success */ + break; + i2c_start(adap); + udelay(adap->udelay); + } + DEB2(if (i) + printk(KERN_DEBUG "i2c-algo-bit.o: Used %d tries to %s client at 0x%02x : %s\n", + i+1, addr & 1 ? "read" : "write", addr>>1, + ret==1 ? "success" : ret==0 ? "no ack" : "failed, timeout?" ) + ); + return ret; +} + +static int sendbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg) +{ + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + char c; + const char *temp = msg->buf; + int count = msg->len; + unsigned short nak_ok = msg->flags & I2C_M_IGNORE_NAK; + int retval; + int wrcount=0; + + while (count > 0) { + c = *temp; + DEB2(dev_dbg(&i2c_adap->dev, "sendbytes: writing %2.2X\n", c&0xff)); + retval = i2c_outb(i2c_adap,c); + if ((retval>0) || (nak_ok && (retval==0))) { /* ok or ignored NAK */ + count--; + temp++; + wrcount++; + } else { /* arbitration or no acknowledge */ + dev_err(&i2c_adap->dev, "sendbytes: error - bailout.\n"); + i2c_stop(adap); + return (retval<0)? retval : -EFAULT; + /* got a better one ?? */ + } +#if 0 + /* from asm/delay.h */ + __delay(adap->mdelay * (loops_per_sec / 1000) ); +#endif + } + return wrcount; +} + +static inline int readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg) +{ + int inval; + int rdcount=0; /* counts bytes read */ + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + char *temp = msg->buf; + int count = msg->len; + + while (count > 0) { + inval = i2c_inb(i2c_adap); +/*printk("%#02x ",inval); if ( ! (count % 16) ) printk("\n"); */ + if (inval>=0) { + *temp = inval; + rdcount++; + } else { /* read timed out */ + printk(KERN_ERR "i2c-algo-bit.o: readbytes: i2c_inb timed out.\n"); + break; + } + + temp++; + count--; + + if (msg->flags & I2C_M_NO_RD_ACK) + continue; + + if ( count > 0 ) { /* send ack */ + sdalo(adap); + DEBPROTO(printk(" Am ")); + } else { + sdahi(adap); /* neg. ack on last byte */ + DEBPROTO(printk(" NAm ")); + } + if (sclhi(adap)<0) { /* timeout */ + sdahi(adap); + printk(KERN_ERR "i2c-algo-bit.o: readbytes: Timeout at ack\n"); + return -ETIMEDOUT; + }; + scllo(adap); + sdahi(adap); + } + return rdcount; +} + +/* doAddress initiates the transfer by generating the start condition (in + * try_address) and transmits the address in the necessary format to handle + * reads, writes as well as 10bit-addresses. + * returns: + * 0 everything went okay, the chip ack'ed, or IGNORE_NAK flag was set + * -x an error occurred (like: -EREMOTEIO if the device did not answer, or + * -ETIMEDOUT, for example if the lines are stuck...) + */ +static inline int bit_doAddress(struct i2c_adapter *i2c_adap, struct i2c_msg *msg) +{ + unsigned short flags = msg->flags; + unsigned short nak_ok = msg->flags & I2C_M_IGNORE_NAK; + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + + unsigned char addr; + int ret, retries; + + retries = nak_ok ? 0 : i2c_adap->retries; + + if ( (flags & I2C_M_TEN) ) { + /* a ten bit address */ + addr = 0xf0 | (( msg->addr >> 7) & 0x03); + DEB2(printk(KERN_DEBUG "addr0: %d\n",addr)); + /* try extended address code...*/ + ret = try_address(i2c_adap, addr, retries); + if ((ret != 1) && !nak_ok) { + printk(KERN_ERR "died at extended address code.\n"); + return -EREMOTEIO; + } + /* the remaining 8 bit address */ + ret = i2c_outb(i2c_adap,msg->addr & 0x7f); + if ((ret != 1) && !nak_ok) { + /* the chip did not ack / xmission error occurred */ + printk(KERN_ERR "died at 2nd address code.\n"); + return -EREMOTEIO; + } + if ( flags & I2C_M_RD ) { + i2c_repstart(adap); + /* okay, now switch into reading mode */ + addr |= 0x01; + ret = try_address(i2c_adap, addr, retries); + if ((ret!=1) && !nak_ok) { + printk(KERN_ERR "died at extended address code.\n"); + return -EREMOTEIO; + } + } + } else { /* normal 7bit address */ + addr = ( msg->addr << 1 ); + if (flags & I2C_M_RD ) + addr |= 1; + if (flags & I2C_M_REV_DIR_ADDR ) + addr ^= 1; + ret = try_address(i2c_adap, addr, retries); + if ((ret!=1) && !nak_ok) + return -EREMOTEIO; + } + + return 0; +} + +static int bit_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg msgs[], int num) +{ + struct i2c_msg *pmsg; + struct i2c_algo_bit_data *adap = i2c_adap->algo_data; + + int i,ret; + unsigned short nak_ok; + + i2c_start(adap); + for (i=0;i<num;i++) { + pmsg = &msgs[i]; + nak_ok = pmsg->flags & I2C_M_IGNORE_NAK; + if (!(pmsg->flags & I2C_M_NOSTART)) { + if (i) { + i2c_repstart(adap); + } + ret = bit_doAddress(i2c_adap, pmsg); + if ((ret != 0) && !nak_ok) { + DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: NAK from device addr %2.2x msg #%d\n" + ,msgs[i].addr,i)); + return (ret<0) ? ret : -EREMOTEIO; + } + } + if (pmsg->flags & I2C_M_RD ) { + /* read bytes into buffer*/ + ret = readbytes(i2c_adap, pmsg); + DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: read %d bytes.\n",ret)); + if (ret < pmsg->len ) { + return (ret<0)? ret : -EREMOTEIO; + } + } else { + /* write bytes from buffer */ + ret = sendbytes(i2c_adap, pmsg); + DEB2(printk(KERN_DEBUG "i2c-algo-bit.o: wrote %d bytes.\n",ret)); + if (ret < pmsg->len ) { + return (ret<0) ? ret : -EREMOTEIO; + } + } + } + i2c_stop(adap); + return num; +} + +static u32 bit_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING; +} + + +/* -----exported algorithm data: ------------------------------------- */ + +static struct i2c_algorithm i2c_bit_algo = { + .name = "Bit-shift algorithm", + .id = I2C_ALGO_BIT, + .master_xfer = bit_xfer, + .functionality = bit_func, +}; + +/* + * registering functions to load algorithms at runtime + */ +int i2c_bit_add_bus(struct i2c_adapter *adap) +{ + struct i2c_algo_bit_data *bit_adap = adap->algo_data; + + if (bit_test) { + int ret = test_bus(bit_adap, adap->name); + if (ret<0) + return -ENODEV; + } + + DEB2(dev_dbg(&adap->dev, "hw routines registered.\n")); + + /* register new adapter to i2c module... */ + + adap->id |= i2c_bit_algo.id; + adap->algo = &i2c_bit_algo; + + adap->timeout = 100; /* default values, should */ + adap->retries = 3; /* be replaced by defines */ + + i2c_add_adapter(adap); + return 0; +} + + +int i2c_bit_del_bus(struct i2c_adapter *adap) +{ + return i2c_del_adapter(adap); +} + +EXPORT_SYMBOL(i2c_bit_add_bus); +EXPORT_SYMBOL(i2c_bit_del_bus); + +MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); +MODULE_DESCRIPTION("I2C-Bus bit-banging algorithm"); +MODULE_LICENSE("GPL"); + +module_param(bit_test, bool, 0); +module_param(i2c_debug, int, S_IRUGO | S_IWUSR); + +MODULE_PARM_DESC(bit_test, "Test the lines of the bus to see if it is stuck"); +MODULE_PARM_DESC(i2c_debug, + "debug level - 0 off; 1 normal; 2,3 more verbose; 9 bit-protocol"); diff --git a/drivers/i2c/algos/i2c-algo-ite.c b/drivers/i2c/algos/i2c-algo-ite.c new file mode 100644 index 00000000000..68e9e6832ca --- /dev/null +++ b/drivers/i2c/algos/i2c-algo-ite.c @@ -0,0 +1,812 @@ +/* + ------------------------------------------------------------------------- + i2c-algo-ite.c i2c driver algorithms for ITE adapters + + Hai-Pao Fan, MontaVista Software, Inc. + hpfan@mvista.com or source@mvista.com + + Copyright 2000 MontaVista Software Inc. + + --------------------------------------------------------------------------- + This file was highly leveraged from i2c-algo-pcf.c, which was created + by Simon G. Vogl and Hans Berglund: + + + Copyright (C) 1995-1997 Simon G. Vogl + 1998-2000 Hans Berglund + + 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. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ +/* ------------------------------------------------------------------------- */ + +/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and + Frodo Looijaard <frodol@dds.nl> ,and also from Martin Bailey + <mbailey@littlefeet-inc.com> */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include <linux/init.h> +#include <asm/uaccess.h> +#include <linux/ioport.h> +#include <linux/errno.h> +#include <linux/sched.h> + +#include <linux/i2c.h> +#include <linux/i2c-algo-ite.h> +#include "i2c-algo-ite.h" + +#define PM_DSR IT8172_PCI_IO_BASE + IT_PM_DSR +#define PM_IBSR IT8172_PCI_IO_BASE + IT_PM_DSR + 0x04 +#define GPIO_CCR IT8172_PCI_IO_BASE + IT_GPCCR + +#define DEB2(x) if (i2c_debug>=2) x +#define DEB3(x) if (i2c_debug>=3) x /* print several statistical values*/ +#define DEF_TIMEOUT 16 + + +/* module parameters: + */ +static int i2c_debug; +static int iic_test; /* see if the line-setting functions work */ + +/* --- setting states on the bus with the right timing: --------------- */ + +#define get_clock(adap) adap->getclock(adap->data) +#define iic_outw(adap, reg, val) adap->setiic(adap->data, reg, val) +#define iic_inw(adap, reg) adap->getiic(adap->data, reg) + + +/* --- other auxiliary functions -------------------------------------- */ + +static void iic_start(struct i2c_algo_iic_data *adap) +{ + iic_outw(adap,ITE_I2CHCR,ITE_CMD); +} + +static void iic_stop(struct i2c_algo_iic_data *adap) +{ + iic_outw(adap,ITE_I2CHCR,0); + iic_outw(adap,ITE_I2CHSR,ITE_I2CHSR_TDI); +} + +static void iic_reset(struct i2c_algo_iic_data *adap) +{ + iic_outw(adap, PM_IBSR, iic_inw(adap, PM_IBSR) | 0x80); +} + + +static int wait_for_bb(struct i2c_algo_iic_data *adap) +{ + int timeout = DEF_TIMEOUT; + short status; + + status = iic_inw(adap, ITE_I2CHSR); +#ifndef STUB_I2C + while (timeout-- && (status & ITE_I2CHSR_HB)) { + udelay(1000); /* How much is this? */ + status = iic_inw(adap, ITE_I2CHSR); + } +#endif + if (timeout<=0) { + printk(KERN_ERR "Timeout, host is busy\n"); + iic_reset(adap); + } + return(timeout<=0); +} + +/* After we issue a transaction on the IIC bus, this function + * is called. It puts this process to sleep until we get an interrupt from + * from the controller telling us that the transaction we requested in complete. + */ +static int wait_for_pin(struct i2c_algo_iic_data *adap, short *status) { + + int timeout = DEF_TIMEOUT; + + timeout = wait_for_bb(adap); + if (timeout) { + DEB2(printk("Timeout waiting for host not busy\n");) + return -EIO; + } + timeout = DEF_TIMEOUT; + + *status = iic_inw(adap, ITE_I2CHSR); +#ifndef STUB_I2C + while (timeout-- && !(*status & ITE_I2CHSR_TDI)) { + adap->waitforpin(); + *status = iic_inw(adap, ITE_I2CHSR); + } +#endif + if (timeout <= 0) + return(-1); + else + return(0); +} + +static int wait_for_fe(struct i2c_algo_iic_data *adap, short *status) +{ + int timeout = DEF_TIMEOUT; + + *status = iic_inw(adap, ITE_I2CFSR); +#ifndef STUB_I2C + while (timeout-- && (*status & ITE_I2CFSR_FE)) { + udelay(1000); + iic_inw(adap, ITE_I2CFSR); + } +#endif + if (timeout <= 0) + return(-1); + else + return(0); +} + +static int iic_init (struct i2c_algo_iic_data *adap) +{ + short i; + + /* Clear bit 7 to set I2C to normal operation mode */ + i=iic_inw(adap, PM_DSR)& 0xff7f; + iic_outw(adap, PM_DSR, i); + + /* set IT_GPCCR port C bit 2&3 as function 2 */ + i = iic_inw(adap, GPIO_CCR) & 0xfc0f; + iic_outw(adap,GPIO_CCR,i); + + /* Clear slave address/sub-address */ + iic_outw(adap,ITE_I2CSAR, 0); + iic_outw(adap,ITE_I2CSSAR, 0); + + /* Set clock counter register */ + iic_outw(adap,ITE_I2CCKCNT, get_clock(adap)); + + /* Set START/reSTART/STOP time registers */ + iic_outw(adap,ITE_I2CSHDR, 0x0a); + iic_outw(adap,ITE_I2CRSUR, 0x0a); + iic_outw(adap,ITE_I2CPSUR, 0x0a); + + /* Enable interrupts on completing the current transaction */ + iic_outw(adap,ITE_I2CHCR, ITE_I2CHCR_IE | ITE_I2CHCR_HCE); + + /* Clear transfer count */ + iic_outw(adap,ITE_I2CFBCR, 0x0); + + DEB2(printk("iic_init: Initialized IIC on ITE 0x%x\n", + iic_inw(adap, ITE_I2CHSR))); + return 0; +} + + +/* + * Sanity check for the adapter hardware - check the reaction of + * the bus lines only if it seems to be idle. + */ +static int test_bus(struct i2c_algo_iic_data *adap, char *name) { +#if 0 + int scl,sda; + sda=getsda(adap); + if (adap->getscl==NULL) { + printk("test_bus: Warning: Adapter can't read from clock line - skipping test.\n"); + return 0; + } + scl=getscl(adap); + printk("test_bus: Adapter: %s scl: %d sda: %d -- testing...\n", + name,getscl(adap),getsda(adap)); + if (!scl || !sda ) { + printk("test_bus: %s seems to be busy.\n",adap->name); + goto bailout; + } + sdalo(adap); + printk("test_bus:1 scl: %d sda: %d \n",getscl(adap), + getsda(adap)); + if ( 0 != getsda(adap) ) { + printk("test_bus: %s SDA stuck high!\n",name); + sdahi(adap); + goto bailout; + } + if ( 0 == getscl(adap) ) { + printk("test_bus: %s SCL unexpected low while pulling SDA low!\n", + name); + goto bailout; + } + sdahi(adap); + printk("test_bus:2 scl: %d sda: %d \n",getscl(adap), + getsda(adap)); + if ( 0 == getsda(adap) ) { + printk("test_bus: %s SDA stuck low!\n",name); + sdahi(adap); + goto bailout; + } + if ( 0 == getscl(adap) ) { + printk("test_bus: %s SCL unexpected low while SDA high!\n", + adap->name); + goto bailout; + } + scllo(adap); + printk("test_bus:3 scl: %d sda: %d \n",getscl(adap), + getsda(adap)); + if ( 0 != getscl(adap) ) { + + sclhi(adap); + goto bailout; + } + if ( 0 == getsda(adap) ) { + printk("test_bus: %s SDA unexpected low while pulling SCL low!\n", + name); + goto bailout; + } + sclhi(adap); + printk("test_bus:4 scl: %d sda: %d \n",getscl(adap), + getsda(adap)); + if ( 0 == getscl(adap) ) { + printk("test_bus: %s SCL stuck low!\n",name); + sclhi(adap); + goto bailout; + } + if ( 0 == getsda(adap) ) { + printk("test_bus: %s SDA unexpected low while SCL high!\n", + name); + goto bailout; + } + printk("test_bus: %s passed test.\n",name); + return 0; +bailout: + sdahi(adap); + sclhi(adap); + return -ENODEV; +#endif + return (0); +} + +/* ----- Utility functions + */ + + +/* Verify the device we want to talk to on the IIC bus really exists. */ +static inline int try_address(struct i2c_algo_iic_data *adap, + unsigned int addr, int retries) +{ + int i, ret = -1; + short status; + + for (i=0;i<retries;i++) { + iic_outw(adap, ITE_I2CSAR, addr); + iic_start(adap); + if (wait_for_pin(adap, &status) == 0) { + if ((status & ITE_I2CHSR_DNE) == 0) { + iic_stop(adap); + iic_outw(adap, ITE_I2CFCR, ITE_I2CFCR_FLUSH); + ret=1; + break; /* success! */ + } + } + iic_stop(adap); + udelay(adap->udelay); + } + DEB2(if (i) printk("try_address: needed %d retries for 0x%x\n",i, + addr)); + return ret; +} + + +static int iic_sendbytes(struct i2c_adapter *i2c_adap,const char *buf, + int count) +{ + struct i2c_algo_iic_data *adap = i2c_adap->algo_data; + int wrcount=0, timeout; + short status; + int loops, remainder, i, j; + union { + char byte[2]; + unsigned short word; + } tmp; + + iic_outw(adap, ITE_I2CSSAR, (unsigned short)buf[wrcount++]); + count--; + if (count == 0) + return -EIO; + + loops = count / 32; /* 32-byte FIFO */ + remainder = count % 32; + + if(loops) { + for(i=0; i<loops; i++) { + + iic_outw(adap, ITE_I2CFBCR, 32); + for(j=0; j<32/2; j++) { + tmp.byte[1] = buf[wrcount++]; + tmp.byte[0] = buf[wrcount++]; + iic_outw(adap, ITE_I2CFDR, tmp.word); + } + + /* status FIFO overrun */ + iic_inw(adap, ITE_I2CFSR); + iic_inw(adap, ITE_I2CFBCR); + + iic_outw(adap, ITE_I2CHCR, ITE_WRITE); /* Issue WRITE command */ + + /* Wait for transmission to complete */ + timeout = wait_for_pin(adap, &status); + if(timeout) { + iic_stop(adap); + printk("iic_sendbytes: %s write timeout.\n", i2c_adap->name); + return -EREMOTEIO; /* got a better one ?? */ + } + if (status & ITE_I2CHSR_DB) { + iic_stop(adap); + printk("iic_sendbytes: %s write error - no ack.\n", i2c_adap->name); + return -EREMOTEIO; /* got a better one ?? */ + } + } + } + if(remainder) { + iic_outw(adap, ITE_I2CFBCR, remainder); + for(i=0; i<remainder/2; i++) { + tmp.byte[1] = buf[wrcount++]; + tmp.byte[0] = buf[wrcount++]; + iic_outw(adap, ITE_I2CFDR, tmp.word); + } + + /* status FIFO overrun */ + iic_inw(adap, ITE_I2CFSR); + iic_inw(adap, ITE_I2CFBCR); + + iic_outw(adap, ITE_I2CHCR, ITE_WRITE); /* Issue WRITE command */ + + timeout = wait_for_pin(adap, &status); + if(timeout) { + iic_stop(adap); + printk("iic_sendbytes: %s write timeout.\n", i2c_adap->name); + return -EREMOTEIO; /* got a better one ?? */ + } +#ifndef STUB_I2C + if (status & ITE_I2CHSR_DB) { + iic_stop(adap); + printk("iic_sendbytes: %s write error - no ack.\n", i2c_adap->name); + return -EREMOTEIO; /* got a better one ?? */ + } +#endif + } + iic_stop(adap); + return wrcount; +} + + +static int iic_readbytes(struct i2c_adapter *i2c_adap, char *buf, int count, + int sread) +{ + int rdcount=0, i, timeout; + short status; + struct i2c_algo_iic_data *adap = i2c_adap->algo_data; + int loops, remainder, j; + union { + char byte[2]; + unsigned short word; + } tmp; |