i2c-algo-bit: Improve debugging
Improve the debugging features of the i2c-algo-bit driver: * Make it possible to compile the driver without debugging support at all, making it much smaller. * Use dev_dbg() for debugging messages where possible, and dev_err() for error messages. * Remove redundant debugging messages. These changes allowed for minor code cleanups, which are included as well. Signed-off-by: Jean Delvare <khali@linux-fr.org>
This commit is contained in:
Jean Delvare
Jean Delvare
parent
424ed67c7d
commit
494dbb64dc
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@ -33,19 +33,30 @@
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/* ----- global defines ----------------------------------------------- */
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#define DEB(x) if (i2c_debug>=1) x;
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#define DEB2(x) if (i2c_debug>=2) x;
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#define DEBSTAT(x) if (i2c_debug>=3) x; /* print several statistical values*/
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#define DEBPROTO(x) if (i2c_debug>=9) { x; }
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/* debug the protocol by showing transferred bits */
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#ifdef DEBUG
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#define bit_dbg(level, dev, format, args...) \
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do { \
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if (i2c_debug >= level) \
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dev_dbg(dev, format, ##args); \
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} while (0)
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#else
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#define bit_dbg(level, dev, format, args...) \
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do {} while (0)
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#endif /* DEBUG */
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/* ----- global variables --------------------------------------------- */
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/* module parameters:
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*/
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static int i2c_debug;
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static int bit_test; /* see if the line-setting functions work */
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module_param(bit_test, bool, 0);
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MODULE_PARM_DESC(bit_test, "Test the lines of the bus to see if it is stuck");
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#ifdef DEBUG
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static int i2c_debug = 1;
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module_param(i2c_debug, int, S_IRUGO | S_IWUSR);
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MODULE_PARM_DESC(i2c_debug,
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"debug level - 0 off; 1 normal; 2 verbose; 3 very verbose");
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#endif
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/* --- setting states on the bus with the right timing: --------------- */
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@ -98,7 +109,11 @@ static int sclhi(struct i2c_algo_bit_data *adap)
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}
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cond_resched();
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}
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DEBSTAT(printk(KERN_DEBUG "needed %ld jiffies\n", jiffies-start));
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#ifdef DEBUG
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if (jiffies != start && i2c_debug >= 3)
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pr_debug("i2c-algo-bit: needed %ld jiffies for SCL to go "
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"high\n", jiffies - start);
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#endif
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done:
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udelay(adap->udelay);
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@ -110,7 +125,6 @@ done:
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static void i2c_start(struct i2c_algo_bit_data *adap)
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{
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/* assert: scl, sda are high */
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DEBPROTO(printk("S "));
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setsda(adap, 0);
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udelay(adap->udelay);
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scllo(adap);
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@ -119,7 +133,6 @@ static void i2c_start(struct i2c_algo_bit_data *adap)
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static void i2c_repstart(struct i2c_algo_bit_data *adap)
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{
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/* assert: scl is low */
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DEBPROTO(printk(" Sr "));
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sdahi(adap);
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sclhi(adap);
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setsda(adap, 0);
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@ -130,7 +143,6 @@ static void i2c_repstart(struct i2c_algo_bit_data *adap)
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static void i2c_stop(struct i2c_algo_bit_data *adap)
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{
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DEBPROTO(printk("P\n"));
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/* assert: scl is low */
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sdalo(adap);
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sclhi(adap);
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@ -147,7 +159,7 @@ static void i2c_stop(struct i2c_algo_bit_data *adap)
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* 0 if the device did not ack
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* -ETIMEDOUT if an error occurred (while raising the scl line)
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*/
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static int i2c_outb(struct i2c_adapter *i2c_adap, char c)
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static int i2c_outb(struct i2c_adapter *i2c_adap, unsigned char c)
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{
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int i;
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int sb;
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@ -156,12 +168,12 @@ static int i2c_outb(struct i2c_adapter *i2c_adap, char c)
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/* assert: scl is low */
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for ( i=7 ; i>=0 ; i-- ) {
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sb = c & ( 1 << i );
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sb = (c >> i) & 1;
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setsda(adap,sb);
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udelay((adap->udelay + 1) / 2);
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DEBPROTO(printk(KERN_DEBUG "%d",sb!=0));
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if (sclhi(adap)<0) { /* timed out */
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DEB2(printk(KERN_DEBUG " i2c_outb: 0x%02x, timeout at bit #%d\n", c&0xff, i));
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bit_dbg(1, &i2c_adap->dev, "i2c_outb: 0x%02x, "
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"timeout at bit #%d\n", (int)c, i);
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return -ETIMEDOUT;
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};
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/* do arbitration here:
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@ -171,17 +183,17 @@ static int i2c_outb(struct i2c_adapter *i2c_adap, char c)
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}
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sdahi(adap);
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if (sclhi(adap)<0){ /* timeout */
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DEB2(printk(KERN_DEBUG " i2c_outb: 0x%02x, timeout at ack\n", c&0xff));
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return -ETIMEDOUT;
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bit_dbg(1, &i2c_adap->dev, "i2c_outb: 0x%02x, "
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"timeout at ack\n", (int)c);
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return -ETIMEDOUT;
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};
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/* read ack: SDA should be pulled down by slave */
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ack=getsda(adap); /* ack: sda is pulled low ->success. */
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DEB2(printk(KERN_DEBUG " i2c_outb: 0x%02x , getsda() = %d\n", c & 0xff, ack));
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ack = !getsda(adap); /* ack: sda is pulled low -> success */
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bit_dbg(2, &i2c_adap->dev, "i2c_outb: 0x%02x %s\n", (int)c,
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ack ? "A" : "NA");
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DEBPROTO( printk(KERN_DEBUG "[%2.2x]",c&0xff) );
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DEBPROTO(if (0==ack){ printk(KERN_DEBUG " A ");} else printk(KERN_DEBUG " NA ") );
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scllo(adap);
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return 0==ack; /* return 1 if device acked */
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return ack;
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/* assert: scl is low (sda undef) */
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}
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@ -198,7 +210,8 @@ static int i2c_inb(struct i2c_adapter *i2c_adap)
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sdahi(adap);
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for (i=0;i<8;i++) {
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if (sclhi(adap)<0) { /* timeout */
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DEB2(printk(KERN_DEBUG " i2c_inb: timeout at bit #%d\n", 7-i));
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bit_dbg(1, &i2c_adap->dev, "i2c_inb: timeout at bit "
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"#%d\n", 7 - i);
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return -ETIMEDOUT;
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};
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indata *= 2;
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@ -208,10 +221,7 @@ static int i2c_inb(struct i2c_adapter *i2c_adap)
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udelay(i == 7 ? adap->udelay / 2 : adap->udelay);
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}
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/* assert: scl is low */
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DEB2(printk(KERN_DEBUG "i2c_inb: 0x%02x\n", indata & 0xff));
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DEBPROTO(printk(KERN_DEBUG " 0x%02x", indata & 0xff));
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return (int) (indata & 0xff);
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return indata;
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}
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/*
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@ -222,73 +232,67 @@ static int test_bus(struct i2c_algo_bit_data *adap, char* name) {
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int scl,sda;
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if (adap->getscl==NULL)
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printk(KERN_INFO "i2c-algo-bit.o: Testing SDA only, "
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"SCL is not readable.\n");
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pr_info("%s: Testing SDA only, SCL is not readable\n", name);
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sda=getsda(adap);
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scl=(adap->getscl==NULL?1:getscl(adap));
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printk(KERN_DEBUG "i2c-algo-bit.o: (0) scl=%d, sda=%d\n",scl,sda);
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if (!scl || !sda ) {
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printk(KERN_WARNING "i2c-algo-bit.o: %s seems to be busy.\n", name);
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printk(KERN_WARNING "%s: bus seems to be busy\n", name);
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goto bailout;
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}
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sdalo(adap);
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sda=getsda(adap);
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scl=(adap->getscl==NULL?1:getscl(adap));
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printk(KERN_DEBUG "i2c-algo-bit.o: (1) scl=%d, sda=%d\n",scl,sda);
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if ( 0 != sda ) {
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printk(KERN_WARNING "i2c-algo-bit.o: SDA stuck high!\n");
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printk(KERN_WARNING "%s: SDA stuck high!\n", name);
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goto bailout;
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}
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if ( 0 == scl ) {
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printk(KERN_WARNING "i2c-algo-bit.o: SCL unexpected low "
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"while pulling SDA low!\n");
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printk(KERN_WARNING "%s: SCL unexpected low "
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"while pulling SDA low!\n", name);
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goto bailout;
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}
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sdahi(adap);
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sda=getsda(adap);
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scl=(adap->getscl==NULL?1:getscl(adap));
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printk(KERN_DEBUG "i2c-algo-bit.o: (2) scl=%d, sda=%d\n",scl,sda);
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if ( 0 == sda ) {
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printk(KERN_WARNING "i2c-algo-bit.o: SDA stuck low!\n");
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printk(KERN_WARNING "%s: SDA stuck low!\n", name);
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goto bailout;
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}
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if ( 0 == scl ) {
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printk(KERN_WARNING "i2c-algo-bit.o: SCL unexpected low "
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"while pulling SDA high!\n");
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printk(KERN_WARNING "%s: SCL unexpected low "
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"while pulling SDA high!\n", name);
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goto bailout;
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}
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scllo(adap);
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sda=getsda(adap);
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scl=(adap->getscl==NULL?0:getscl(adap));
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printk(KERN_DEBUG "i2c-algo-bit.o: (3) scl=%d, sda=%d\n",scl,sda);
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if ( 0 != scl ) {
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printk(KERN_WARNING "i2c-algo-bit.o: SCL stuck high!\n");
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printk(KERN_WARNING "%s: SCL stuck high!\n", name);
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goto bailout;
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}
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if ( 0 == sda ) {
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printk(KERN_WARNING "i2c-algo-bit.o: SDA unexpected low "
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"while pulling SCL low!\n");
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printk(KERN_WARNING "%s: SDA unexpected low "
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"while pulling SCL low!\n", name);
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goto bailout;
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}
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sclhi(adap);
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sda=getsda(adap);
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scl=(adap->getscl==NULL?1:getscl(adap));
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printk(KERN_DEBUG "i2c-algo-bit.o: (4) scl=%d, sda=%d\n",scl,sda);
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if ( 0 == scl ) {
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printk(KERN_WARNING "i2c-algo-bit.o: SCL stuck low!\n");
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printk(KERN_WARNING "%s: SCL stuck low!\n", name);
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goto bailout;
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}
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if ( 0 == sda ) {
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printk(KERN_WARNING "i2c-algo-bit.o: SDA unexpected low "
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"while pulling SCL high!\n");
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printk(KERN_WARNING "%s: SDA unexpected low "
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"while pulling SCL high!\n", name);
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goto bailout;
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}
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printk(KERN_INFO "i2c-algo-bit.o: %s passed test.\n",name);
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pr_info("%s: Test OK\n", name);
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return 0;
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bailout:
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sdahi(adap);
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@ -315,32 +319,31 @@ static int try_address(struct i2c_adapter *i2c_adap,
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ret = i2c_outb(i2c_adap,addr);
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if (ret == 1 || i == retries)
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break;
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bit_dbg(3, &i2c_adap->dev, "emitting stop condition\n");
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i2c_stop(adap);
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udelay(adap->udelay);
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yield();
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bit_dbg(3, &i2c_adap->dev, "emitting start condition\n");
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i2c_start(adap);
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}
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DEB2(if (i)
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printk(KERN_DEBUG "i2c-algo-bit.o: Used %d tries to %s client at 0x%02x : %s\n",
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i+1, addr & 1 ? "read" : "write", addr>>1,
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ret==1 ? "success" : ret==0 ? "no ack" : "failed, timeout?" )
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);
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if (i && ret)
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bit_dbg(1, &i2c_adap->dev, "Used %d tries to %s client at "
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"0x%02x: %s\n", i + 1,
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addr & 1 ? "read from" : "write to", addr >> 1,
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ret == 1 ? "success" : "failed, timeout?");
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return ret;
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}
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static int sendbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
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{
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char c;
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const char *temp = msg->buf;
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const unsigned char *temp = msg->buf;
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int count = msg->len;
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unsigned short nak_ok = msg->flags & I2C_M_IGNORE_NAK;
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int retval;
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int wrcount=0;
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while (count > 0) {
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c = *temp;
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DEB2(dev_dbg(&i2c_adap->dev, "sendbytes: writing %2.2X\n", c&0xff));
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retval = i2c_outb(i2c_adap,c);
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retval = i2c_outb(i2c_adap, *temp);
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if ((retval>0) || (nak_ok && (retval==0))) { /* ok or ignored NAK */
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count--;
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temp++;
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@ -359,7 +362,7 @@ static int readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
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int inval;
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int rdcount=0; /* counts bytes read */
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struct i2c_algo_bit_data *adap = i2c_adap->algo_data;
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char *temp = msg->buf;
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unsigned char *temp = msg->buf;
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int count = msg->len;
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while (count > 0) {
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@ -368,28 +371,26 @@ static int readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
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*temp = inval;
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rdcount++;
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} else { /* read timed out */
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printk(KERN_ERR "i2c-algo-bit.o: readbytes: i2c_inb timed out.\n");
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break;
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}
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temp++;
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count--;
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if (msg->flags & I2C_M_NO_RD_ACK)
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if (msg->flags & I2C_M_NO_RD_ACK) {
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bit_dbg(2, &i2c_adap->dev, "i2c_inb: 0x%02x\n",
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inval);
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continue;
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}
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/* assert: sda is high */
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if ( count > 0 ) { /* send ack */
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if (count) /* send ack */
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setsda(adap, 0);
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udelay((adap->udelay + 1) / 2);
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DEBPROTO(printk(" Am "));
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} else {
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/* neg. ack on last byte */
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udelay((adap->udelay + 1) / 2);
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DEBPROTO(printk(" NAm "));
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}
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udelay((adap->udelay + 1) / 2);
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bit_dbg(2, &i2c_adap->dev, "i2c_inb: 0x%02x %s\n", inval,
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count ? "A" : "NA");
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if (sclhi(adap)<0) { /* timeout */
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printk(KERN_ERR "i2c-algo-bit.o: readbytes: Timeout at ack\n");
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dev_err(&i2c_adap->dev, "readbytes: timeout at ack\n");
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return -ETIMEDOUT;
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};
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scllo(adap);
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@ -398,8 +399,8 @@ static int readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
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transaction length as the first read byte. */
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if (rdcount == 1 && (msg->flags & I2C_M_RECV_LEN)) {
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if (inval <= 0 || inval > I2C_SMBUS_BLOCK_MAX) {
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printk(KERN_ERR "i2c-algo-bit: readbytes: "
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"invalid block length (%d)\n", inval);
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dev_err(&i2c_adap->dev, "readbytes: invalid "
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"block length (%d)\n", inval);
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return -EREMOTEIO;
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}
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/* The original count value accounts for the extra
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@ -434,27 +435,31 @@ static int bit_doAddress(struct i2c_adapter *i2c_adap, struct i2c_msg *msg)
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if ( (flags & I2C_M_TEN) ) {
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/* a ten bit address */
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addr = 0xf0 | (( msg->addr >> 7) & 0x03);
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DEB2(printk(KERN_DEBUG "addr0: %d\n",addr));
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bit_dbg(2, &i2c_adap->dev, "addr0: %d\n", addr);
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/* try extended address code...*/
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ret = try_address(i2c_adap, addr, retries);
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if ((ret != 1) && !nak_ok) {
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printk(KERN_ERR "died at extended address code.\n");
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dev_err(&i2c_adap->dev,
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"died at extended address code\n");
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return -EREMOTEIO;
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}
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/* the remaining 8 bit address */
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ret = i2c_outb(i2c_adap,msg->addr & 0x7f);
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if ((ret != 1) && !nak_ok) {
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/* the chip did not ack / xmission error occurred */
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printk(KERN_ERR "died at 2nd address code.\n");
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dev_err(&i2c_adap->dev, "died at 2nd address code\n");
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return -EREMOTEIO;
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}
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if ( flags & I2C_M_RD ) {
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bit_dbg(3, &i2c_adap->dev, "emitting repeated "
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"start condition\n");
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i2c_repstart(adap);
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/* okay, now switch into reading mode */
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addr |= 0x01;
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ret = try_address(i2c_adap, addr, retries);
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if ((ret!=1) && !nak_ok) {
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printk(KERN_ERR "died at extended address code.\n");
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dev_err(&i2c_adap->dev,
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"died at repeated address code\n");
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return -EREMOTEIO;
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}
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}
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@ -481,25 +486,31 @@ static int bit_xfer(struct i2c_adapter *i2c_adap,
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int i,ret;
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unsigned short nak_ok;
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bit_dbg(3, &i2c_adap->dev, "emitting start condition\n");
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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");
|
||||
|
|
|
|||
Loading…
Reference in New Issue