/* * This should perform the 'PCF8584 initialization sequence' as described * in the Philips IC12 data book (1995, Aug 29). * There should be a 30 clock cycle wait after reset, I assume this * has been fulfilled. * There should be a delay at the end equal to the longest I2C message * to synchronize the BB-bit (in multimaster systems). How long is * this? I assume 1 second is always long enough. * * vdovikin: added detect code for PCF8584 */ static int pcf_init_8584 (struct i2c_algo_pcf_data *adap) { unsigned char temp; // DEB3(printk(KERN_DEBUG "i2c-algo-pcf.o: PCF state 0x%02x\n", ; /* S1=0x80: S0 selected, serial interface off */ set_pcf(adap, 1, I2C_PCF_PIN); /* * check to see S1 now used as R/W ctrl - * PCF8584 does that when ESO is zero */ if (((temp = get_pcf(adap, 1)) & 0x7f) != (0)) { ; return -ENXIO; /* definitely not PCF8584 */ } /* load own address in S0, effective address is (own << 1) */ i2c_outb(adap, get_own(adap)); /* check it's really written */ if ((temp = i2c_inb(adap)) != get_own(adap)) { ; return -ENXIO; } /* S1=0xA0, next byte in S2 */ set_pcf(adap, 1, I2C_PCF_PIN | I2C_PCF_ES1); /* check to see S2 now selected */ if (((temp = get_pcf(adap, 1)) & 0x7f) != I2C_PCF_ES1) { ; return -ENXIO; } /* load clock register S2 */ i2c_outb(adap, get_clock(adap)); /* check it's really written, the only 5 lowest bits does matter */ if (((temp = i2c_inb(adap)) & 0x1f) != get_clock(adap)) { ; return -ENXIO; } /* Enable serial interface, idle, S0 selected */ set_pcf(adap, 1, I2C_PCF_IDLE); /* check to see PCF is really idled and we can access status register */ if ((temp = get_pcf(adap, 1)) != (I2C_PCF_PIN | I2C_PCF_BB)) { ; return -ENXIO; } ; return 0; }
static int pcf_init_8584 (struct i2c_algo_pcf_data *adap) { unsigned char temp; DEB3(printk(KERN_DEBUG "i2c-algo-pcf.o: PCF state 0x%02x\n", get_pcf(adap, 1))); /* */ set_pcf(adap, 1, I2C_PCF_PIN); /* */ if (((temp = get_pcf(adap, 1)) & 0x7f) != (0)) { DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S0 (0x%02x).\n", temp)); return -ENXIO; /* */ } /* */ i2c_outb(adap, get_own(adap)); /* */ if ((temp = i2c_inb(adap)) != get_own(adap)) { DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't set S0 (0x%02x).\n", temp)); return -ENXIO; } /* */ set_pcf(adap, 1, I2C_PCF_PIN | I2C_PCF_ES1); /* */ if (((temp = get_pcf(adap, 1)) & 0x7f) != I2C_PCF_ES1) { DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S2 (0x%02x).\n", temp)); return -ENXIO; } /* */ i2c_outb(adap, get_clock(adap)); /* */ if (((temp = i2c_inb(adap)) & 0x1f) != get_clock(adap)) { DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't set S2 (0x%02x).\n", temp)); return -ENXIO; } /* */ set_pcf(adap, 1, I2C_PCF_IDLE); /* */ if ((temp = get_pcf(adap, 1)) != (I2C_PCF_PIN | I2C_PCF_BB)) { DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S1` (0x%02x).\n", temp)); return -ENXIO; } printk(KERN_DEBUG "i2c-algo-pcf.o: detected and initialized PCF8584.\n"); return 0; }