diff options
| -rw-r--r-- | drivers/i2c/algos/i2c-algo-bit.c | 185 |
1 files changed, 95 insertions, 90 deletions
diff --git a/drivers/i2c/algos/i2c-algo-bit.c b/drivers/i2c/algos/i2c-algo-bit.c index d9d0ec49e60..8a5f5825bb7 100644 --- a/drivers/i2c/algos/i2c-algo-bit.c +++ b/drivers/i2c/algos/i2c-algo-bit.c @@ -33,19 +33,30 @@ /* ----- 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 */ +#ifdef DEBUG +#define bit_dbg(level, dev, format, args...) \ + do { \ + if (i2c_debug >= level) \ + dev_dbg(dev, format, ##args); \ + } while (0) +#else +#define bit_dbg(level, dev, format, args...) \ + do {} while (0) +#endif /* DEBUG */ /* ----- global variables --------------------------------------------- */ -/* module parameters: - */ -static int i2c_debug; static int bit_test; /* see if the line-setting functions work */ +module_param(bit_test, bool, 0); +MODULE_PARM_DESC(bit_test, "Test the lines of the bus to see if it is stuck"); + +#ifdef DEBUG +static int i2c_debug = 1; +module_param(i2c_debug, int, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(i2c_debug, + "debug level - 0 off; 1 normal; 2 verbose; 3 very verbose"); +#endif /* --- setting states on the bus with the right timing: --------------- */ @@ -98,7 +109,11 @@ static int sclhi(struct i2c_algo_bit_data *adap) } cond_resched(); } - DEBSTAT(printk(KERN_DEBUG "needed %ld jiffies\n", jiffies-start)); +#ifdef DEBUG + if (jiffies != start && i2c_debug >= 3) + pr_debug("i2c-algo-bit: needed %ld jiffies for SCL to go " + "high\n", jiffies - start); +#endif done: udelay(adap->udelay); @@ -110,7 +125,6 @@ done: static void i2c_start(struct i2c_algo_bit_data *adap) { /* assert: scl, sda are high */ - DEBPROTO(printk("S ")); setsda(adap, 0); udelay(adap->udelay); scllo(adap); @@ -119,7 +133,6 @@ static void i2c_start(struct i2c_algo_bit_data *adap) static void i2c_repstart(struct i2c_algo_bit_data *adap) { /* assert: scl is low */ - DEBPROTO(printk(" Sr ")); sdahi(adap); sclhi(adap); setsda(adap, 0); @@ -130,7 +143,6 @@ static void i2c_repstart(struct i2c_algo_bit_data *adap) static void i2c_stop(struct i2c_algo_bit_data *adap) { - DEBPROTO(printk("P\n")); /* assert: scl is low */ sdalo(adap); sclhi(adap); @@ -147,7 +159,7 @@ static void i2c_stop(struct i2c_algo_bit_data *adap) * 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) +static int i2c_outb(struct i2c_adapter *i2c_adap, unsigned char c) { int i; int sb; @@ -156,12 +168,12 @@ static int i2c_outb(struct i2c_adapter *i2c_adap, char c) /* assert: scl is low */ for ( i=7 ; i>=0 ; i-- ) { - sb = c & ( 1 << i ); + sb = (c >> i) & 1; setsda(adap,sb); udelay((adap->udelay + 1) / 2); - DEBPROTO(printk(KERN_DEBUG "%d",sb!=0)); if (sclhi(adap)<0) { /* timed out */ - DEB2(printk(KERN_DEBUG " i2c_outb: 0x%02x, timeout at bit #%d\n", c&0xff, i)); + bit_dbg(1, &i2c_adap->dev, "i2c_outb: 0x%02x, " + "timeout at bit #%d\n", (int)c, i); return -ETIMEDOUT; }; /* do arbitration here: @@ -171,17 +183,17 @@ static int i2c_outb(struct i2c_adapter *i2c_adap, char c) } sdahi(adap); if (sclhi(adap)<0){ /* timeout */ - DEB2(printk(KERN_DEBUG " i2c_outb: 0x%02x, timeout at ack\n", c&0xff)); - return -ETIMEDOUT; + bit_dbg(1, &i2c_adap->dev, "i2c_outb: 0x%02x, " + "timeout at ack\n", (int)c); + 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)); + ack = !getsda(adap); /* ack: sda is pulled low -> success */ + bit_dbg(2, &i2c_adap->dev, "i2c_outb: 0x%02x %s\n", (int)c, + ack ? "A" : "NA"); - 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 */ + return ack; /* assert: scl is low (sda undef) */ } @@ -198,7 +210,8 @@ static int i2c_inb(struct i2c_adapter *i2c_adap) 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)); + bit_dbg(1, &i2c_adap->dev, "i2c_inb: timeout at bit " + "#%d\n", 7 - i); return -ETIMEDOUT; }; indata *= 2; @@ -208,10 +221,7 @@ static int i2c_inb(struct i2c_adapter *i2c_adap) udelay(i == 7 ? adap->udelay / 2 : adap->udelay); } /* 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); + return indata; } /* @@ -222,73 +232,67 @@ 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"); + pr_info("%s: Testing SDA only, SCL is not readable\n", name); 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); + printk(KERN_WARNING "%s: bus 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"); + printk(KERN_WARNING "%s: SDA stuck high!\n", name); goto bailout; } if ( 0 == scl ) { - printk(KERN_WARNING "i2c-algo-bit.o: SCL unexpected low " - "while pulling SDA low!\n"); + printk(KERN_WARNING "%s: SCL unexpected low " + "while pulling SDA low!\n", name); 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"); + printk(KERN_WARNING "%s: SDA stuck low!\n", name); goto bailout; } if ( 0 == scl ) { - printk(KERN_WARNING "i2c-algo-bit.o: SCL unexpected low " - "while pulling SDA high!\n"); + printk(KERN_WARNING "%s: SCL unexpected low " + "while pulling SDA high!\n", name); 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"); + printk(KERN_WARNING "%s: SCL stuck high!\n", name); goto bailout; } if ( 0 == sda ) { - printk(KERN_WARNING "i2c-algo-bit.o: SDA unexpected low " - "while pulling SCL low!\n"); + printk(KERN_WARNING "%s: SDA unexpected low " + "while pulling SCL low!\n", name); 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"); + printk(KERN_WARNING "%s: SCL stuck low!\n", name); goto bailout; } if ( 0 == sda ) { - printk(KERN_WARNING "i2c-algo-bit.o: SDA unexpected low " - "while pulling SCL high!\n"); + printk(KERN_WARNING "%s: SDA unexpected low " + "while pulling SCL high!\n", name); goto bailout; } - printk(KERN_INFO "i2c-algo-bit.o: %s passed test.\n",name); + pr_info("%s: Test OK\n", name); return 0; bailout: sdahi(adap); @@ -315,32 +319,31 @@ static int try_address(struct i2c_adapter *i2c_adap, ret = i2c_outb(i2c_adap,addr); if (ret == 1 || i == retries) break; + bit_dbg(3, &i2c_adap->dev, "emitting stop condition\n"); i2c_stop(adap); udelay(adap->udelay); yield(); + bit_dbg(3, &i2c_adap->dev, "emitting start condition\n"); i2c_start(adap); } - 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?" ) - ); + if (i && ret) + bit_dbg(1, &i2c_adap->dev, "Used %d tries to %s client at " + "0x%02x: %s\n", i + 1, + addr & 1 ? "read from" : "write to", addr >> 1, + ret == 1 ? "success" : "failed, timeout?"); return ret; } static int sendbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg) { - char c; - const char *temp = msg->buf; + const unsigned 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); + retval = i2c_outb(i2c_adap, *temp); if ((retval>0) || (nak_ok && (retval==0))) { /* ok or ignored NAK */ count--; temp++; @@ -359,7 +362,7 @@ static 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; + unsigned char *temp = msg->buf; int count = msg->len; while (count > 0) { @@ -368,28 +371,26 @@ static int readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg) *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) + if (msg->flags & I2C_M_NO_RD_ACK) { + bit_dbg(2, &i2c_adap->dev, "i2c_inb: 0x%02x\n", + inval); continue; + } /* assert: sda is high */ - if ( count > 0 ) { /* send ack */ + if (count) /* send ack */ setsda(adap, 0); - udelay((adap->udelay + 1) / 2); - DEBPROTO(printk(" Am ")); - } else { - /* neg. ack on last byte */ - udelay((adap->udelay + 1) / 2); - DEBPROTO(printk(" NAm ")); - } + udelay((adap->udelay + 1) / 2); + bit_dbg(2, &i2c_adap->dev, "i2c_inb: 0x%02x %s\n", inval, + count ? "A" : "NA"); if (sclhi(adap)<0) { /* timeout */ - printk(KERN_ERR "i2c-algo-bit.o: readbytes: Timeout at ack\n"); + dev_err(&i2c_adap->dev, "readbytes: timeout at ack\n"); return -ETIMEDOUT; }; scllo(adap); @@ -398,8 +399,8 @@ static int readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg) transaction length as the first read byte. */ if (rdcount == 1 && (msg->flags & I2C_M_RECV_LEN)) { if (inval <= 0 || inval > I2C_SMBUS_BLOCK_MAX) { - printk(KERN_ERR "i2c-algo-bit: readbytes: " - "invalid block length (%d)\n", inval); + dev_err(&i2c_adap->dev, "readbytes: invalid " + "block length (%d)\n", inval); return -EREMOTEIO; } /* The original count value accounts for the extra @@ -434,27 +435,31 @@ static int bit_doAddress(struct i2c_adapter *i2c_adap, struct i2c_msg *msg) if ( (flags & I2C_M_TEN) ) { /* a ten bit address */ addr = 0xf0 | (( msg->addr >> 7) & 0x03); - DEB2(printk(KERN_DEBUG "addr0: %d\n",addr)); + bit_dbg(2, &i2c_adap->dev, "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"); + dev_err(&i2c_adap->dev, + "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"); + dev_err(&i2c_adap->dev, "died at 2nd address code\n"); return -EREMOTEIO; } if ( flags & I2C_M_RD ) { + bit_dbg(3, &i2c_adap->dev, "emitting repeated " + "start condition\n"); 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"); + dev_err(&i2c_adap->dev, + "died at repeated address code\n"); return -EREMOTEIO; } } @@ -481,25 +486,31 @@ static int bit_xfer(struct i2c_adapter *i2c_adap, int i,ret; unsigned short nak_ok; + bit_dbg(3, &i2c_adap->dev, "emitting start condition\n"); 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) { + bit_dbg(3, &i2c_adap->dev, "emitting " + "repeated start condition\n"); 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)); + bit_dbg(1, &i2c_adap->dev, "NAK from " + "device addr 0x%02x msg #%d\n", + msgs[i].addr, i); goto bailout; } } 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 >= 1) + bit_dbg(2, &i2c_adap->dev, "read %d byte%s\n", + ret, ret == 1 ? "" : "s"); if (ret < pmsg->len) { if (ret >= 0) ret = -EREMOTEIO; @@ -508,7 +519,9 @@ static int bit_xfer(struct i2c_adapter *i2c_adap, } 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 >= 1) + bit_dbg(2, &i2c_adap->dev, "wrote %d byte%s\n", + ret, ret == 1 ? "" : "s"); if (ret < pmsg->len) { if (ret >= 0) ret = -EREMOTEIO; @@ -519,6 +532,7 @@ static int bit_xfer(struct i2c_adapter *i2c_adap, ret = i; bailout: + bit_dbg(3, &i2c_adap->dev, "emitting stop condition\n"); i2c_stop(adap); return ret; } @@ -552,8 +566,6 @@ static int i2c_bit_prepare_bus(struct i2c_adapter *adap) return -ENODEV; } - DEB2(dev_dbg(&adap->dev, "hw routines registered.\n")); - /* register new adapter to i2c module... */ adap->algo = &i2c_bit_algo; @@ -590,10 +602,3 @@ EXPORT_SYMBOL(i2c_bit_add_numbered_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"); |