X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fi2c%2Fbusses%2Fi2c-ibm_iic.c;h=1898e9987021606c78af90c3b97869066355aa7d;hb=refs%2Fremotes%2Fvserver;hp=962184be1899c3bd5bbfb8a22d9b41c747cc92fd;hpb=9213980e6a70d8473e0ffd4b39ab5b6caaba9ff5;p=linux-2.6.git diff --git a/drivers/i2c/busses/i2c-ibm_iic.c b/drivers/i2c/busses/i2c-ibm_iic.c index 962184be1..1898e9987 100644 --- a/drivers/i2c/busses/i2c-ibm_iic.c +++ b/drivers/i2c/busses/i2c-ibm_iic.c @@ -1,5 +1,5 @@ /* - * drivers/i2c/i2c-ibm_iic.c + * drivers/i2c/busses/i2c-ibm_iic.c * * Support for the IIC peripheral on IBM PPC 4xx * @@ -28,7 +28,6 @@ * */ -#include #include #include #include @@ -45,17 +44,17 @@ #include "i2c-ibm_iic.h" -#define DRIVER_VERSION "2.01" +#define DRIVER_VERSION "2.1" MODULE_DESCRIPTION("IBM IIC driver v" DRIVER_VERSION); MODULE_LICENSE("GPL"); -static int iic_force_poll = 0; -MODULE_PARM(iic_force_poll, "i"); +static int iic_force_poll; +module_param(iic_force_poll, bool, 0); MODULE_PARM_DESC(iic_force_poll, "Force polling mode"); -static int iic_force_fast = 0; -MODULE_PARM(iic_force_fast, "i"); +static int iic_force_fast; +module_param(iic_force_fast, bool, 0); MODULE_PARM_DESC(iic_fast_poll, "Force fast mode (400 kHz)"); #define DBG_LEVEL 0 @@ -81,7 +80,7 @@ MODULE_PARM_DESC(iic_fast_poll, "Force fast mode (400 kHz)"); #if DBG_LEVEL > 2 static void dump_iic_regs(const char* header, struct ibm_iic_private* dev) { - volatile struct iic_regs *iic = dev->vaddr; + volatile struct iic_regs __iomem *iic = dev->vaddr; printk(KERN_DEBUG "ibm-iic%d: %s\n", dev->idx, header); printk(KERN_DEBUG " cntl = 0x%02x, mdcntl = 0x%02x\n" KERN_DEBUG " sts = 0x%02x, extsts = 0x%02x\n" @@ -96,6 +95,31 @@ static void dump_iic_regs(const char* header, struct ibm_iic_private* dev) # define DUMP_REGS(h,dev) ((void)0) #endif +/* Bus timings (in ns) for bit-banging */ +static struct i2c_timings { + unsigned int hd_sta; + unsigned int su_sto; + unsigned int low; + unsigned int high; + unsigned int buf; +} timings [] = { +/* Standard mode (100 KHz) */ +{ + .hd_sta = 4000, + .su_sto = 4000, + .low = 4700, + .high = 4000, + .buf = 4700, +}, +/* Fast mode (400 KHz) */ +{ + .hd_sta = 600, + .su_sto = 600, + .low = 1300, + .high = 600, + .buf = 1300, +}}; + /* Enable/disable interrupt generation */ static inline void iic_interrupt_mode(struct ibm_iic_private* dev, int enable) { @@ -107,7 +131,7 @@ static inline void iic_interrupt_mode(struct ibm_iic_private* dev, int enable) */ static void iic_dev_init(struct ibm_iic_private* dev) { - volatile struct iic_regs *iic = dev->vaddr; + volatile struct iic_regs __iomem *iic = dev->vaddr; DBG("%d: init\n", dev->idx); @@ -152,7 +176,7 @@ static void iic_dev_init(struct ibm_iic_private* dev) */ static void iic_dev_reset(struct ibm_iic_private* dev) { - volatile struct iic_regs *iic = dev->vaddr; + volatile struct iic_regs __iomem *iic = dev->vaddr; int i; u8 dc; @@ -195,13 +219,111 @@ static void iic_dev_reset(struct ibm_iic_private* dev) iic_dev_init(dev); } +/* + * Do 0-length transaction using bit-banging through IIC_DIRECTCNTL register. + */ + +/* Wait for SCL and/or SDA to be high */ +static int iic_dc_wait(volatile struct iic_regs __iomem *iic, u8 mask) +{ + unsigned long x = jiffies + HZ / 28 + 2; + while ((in_8(&iic->directcntl) & mask) != mask){ + if (unlikely(time_after(jiffies, x))) + return -1; + cond_resched(); + } + return 0; +} + +static int iic_smbus_quick(struct ibm_iic_private* dev, const struct i2c_msg* p) +{ + volatile struct iic_regs __iomem *iic = dev->vaddr; + const struct i2c_timings* t = &timings[dev->fast_mode ? 1 : 0]; + u8 mask, v, sda; + int i, res; + + /* Only 7-bit addresses are supported */ + if (unlikely(p->flags & I2C_M_TEN)){ + DBG("%d: smbus_quick - 10 bit addresses are not supported\n", + dev->idx); + return -EINVAL; + } + + DBG("%d: smbus_quick(0x%02x)\n", dev->idx, p->addr); + + /* Reset IIC interface */ + out_8(&iic->xtcntlss, XTCNTLSS_SRST); + + /* Wait for bus to become free */ + out_8(&iic->directcntl, DIRCNTL_SDAC | DIRCNTL_SCC); + if (unlikely(iic_dc_wait(iic, DIRCNTL_MSDA | DIRCNTL_MSC))) + goto err; + ndelay(t->buf); + + /* START */ + out_8(&iic->directcntl, DIRCNTL_SCC); + sda = 0; + ndelay(t->hd_sta); + + /* Send address */ + v = (u8)((p->addr << 1) | ((p->flags & I2C_M_RD) ? 1 : 0)); + for (i = 0, mask = 0x80; i < 8; ++i, mask >>= 1){ + out_8(&iic->directcntl, sda); + ndelay(t->low / 2); + sda = (v & mask) ? DIRCNTL_SDAC : 0; + out_8(&iic->directcntl, sda); + ndelay(t->low / 2); + + out_8(&iic->directcntl, DIRCNTL_SCC | sda); + if (unlikely(iic_dc_wait(iic, DIRCNTL_MSC))) + goto err; + ndelay(t->high); + } + + /* ACK */ + out_8(&iic->directcntl, sda); + ndelay(t->low / 2); + out_8(&iic->directcntl, DIRCNTL_SDAC); + ndelay(t->low / 2); + out_8(&iic->directcntl, DIRCNTL_SDAC | DIRCNTL_SCC); + if (unlikely(iic_dc_wait(iic, DIRCNTL_MSC))) + goto err; + res = (in_8(&iic->directcntl) & DIRCNTL_MSDA) ? -EREMOTEIO : 1; + ndelay(t->high); + + /* STOP */ + out_8(&iic->directcntl, 0); + ndelay(t->low); + out_8(&iic->directcntl, DIRCNTL_SCC); + if (unlikely(iic_dc_wait(iic, DIRCNTL_MSC))) + goto err; + ndelay(t->su_sto); + out_8(&iic->directcntl, DIRCNTL_SDAC | DIRCNTL_SCC); + + ndelay(t->buf); + + DBG("%d: smbus_quick -> %s\n", dev->idx, res ? "NACK" : "ACK"); +out: + /* Remove reset */ + out_8(&iic->xtcntlss, 0); + + /* Reinitialize interface */ + iic_dev_init(dev); + + return res; +err: + DBG("%d: smbus_quick - bus is stuck\n", dev->idx); + res = -EREMOTEIO; + goto out; +} + /* * IIC interrupt handler */ -static irqreturn_t iic_handler(int irq, void *dev_id, struct pt_regs *regs) +static irqreturn_t iic_handler(int irq, void *dev_id) { struct ibm_iic_private* dev = (struct ibm_iic_private*)dev_id; - volatile struct iic_regs* iic = dev->vaddr; + volatile struct iic_regs __iomem *iic = dev->vaddr; DBG2("%d: irq handler, STS = 0x%02x, EXTSTS = 0x%02x\n", dev->idx, in_8(&iic->sts), in_8(&iic->extsts)); @@ -219,7 +341,7 @@ static irqreturn_t iic_handler(int irq, void *dev_id, struct pt_regs *regs) */ static int iic_xfer_result(struct ibm_iic_private* dev) { - volatile struct iic_regs *iic = dev->vaddr; + volatile struct iic_regs __iomem *iic = dev->vaddr; if (unlikely(in_8(&iic->sts) & STS_ERR)){ DBG("%d: xfer error, EXTSTS = 0x%02x\n", dev->idx, @@ -252,7 +374,7 @@ static int iic_xfer_result(struct ibm_iic_private* dev) */ static void iic_abort_xfer(struct ibm_iic_private* dev) { - volatile struct iic_regs *iic = dev->vaddr; + volatile struct iic_regs __iomem *iic = dev->vaddr; unsigned long x; DBG("%d: iic_abort_xfer\n", dev->idx); @@ -284,25 +406,17 @@ static void iic_abort_xfer(struct ibm_iic_private* dev) */ static int iic_wait_for_tc(struct ibm_iic_private* dev){ - volatile struct iic_regs *iic = dev->vaddr; + volatile struct iic_regs __iomem *iic = dev->vaddr; int ret = 0; if (dev->irq >= 0){ /* Interrupt mode */ - wait_queue_t wait; - init_waitqueue_entry(&wait, current); - - add_wait_queue(&dev->wq, &wait); - set_current_state(TASK_INTERRUPTIBLE); - if (in_8(&iic->sts) & STS_PT) - schedule_timeout(dev->adap.timeout * HZ); - set_current_state(TASK_RUNNING); - remove_wait_queue(&dev->wq, &wait); - - if (unlikely(signal_pending(current))){ + ret = wait_event_interruptible_timeout(dev->wq, + !(in_8(&iic->sts) & STS_PT), dev->adap.timeout * HZ); + + if (unlikely(ret < 0)) DBG("%d: wait interrupted\n", dev->idx); - ret = -ERESTARTSYS; - } else if (unlikely(in_8(&iic->sts) & STS_PT)){ + else if (unlikely(in_8(&iic->sts) & STS_PT)){ DBG("%d: wait timeout\n", dev->idx); ret = -ETIMEDOUT; } @@ -343,7 +457,7 @@ static int iic_wait_for_tc(struct ibm_iic_private* dev){ static int iic_xfer_bytes(struct ibm_iic_private* dev, struct i2c_msg* pm, int combined_xfer) { - volatile struct iic_regs *iic = dev->vaddr; + volatile struct iic_regs __iomem *iic = dev->vaddr; char* buf = pm->buf; int i, j, loops, ret = 0; int len = pm->len; @@ -359,7 +473,7 @@ static int iic_xfer_bytes(struct ibm_iic_private* dev, struct i2c_msg* pm, if (!(cntl & CNTL_RW)) for (j = 0; j < count; ++j) - out_8((volatile u8*)&iic->mdbuf, *buf++); + out_8((void __iomem *)&iic->mdbuf, *buf++); if (i < loops - 1) cmd |= CNTL_CHT; @@ -390,7 +504,7 @@ static int iic_xfer_bytes(struct ibm_iic_private* dev, struct i2c_msg* pm, if (cntl & CNTL_RW) for (j = 0; j < count; ++j) - *buf++ = in_8((volatile u8*)&iic->mdbuf); + *buf++ = in_8((void __iomem *)&iic->mdbuf); } return ret > 0 ? 0 : ret; @@ -401,7 +515,7 @@ static int iic_xfer_bytes(struct ibm_iic_private* dev, struct i2c_msg* pm, */ static inline void iic_address(struct ibm_iic_private* dev, struct i2c_msg* msg) { - volatile struct iic_regs *iic = dev->vaddr; + volatile struct iic_regs __iomem *iic = dev->vaddr; u16 addr = msg->addr; DBG2("%d: iic_address, 0x%03x (%d-bit)\n", dev->idx, @@ -434,10 +548,10 @@ static inline int iic_address_neq(const struct i2c_msg* p1, * Generic master transfer entrypoint. * Returns the number of processed messages or error (<0) */ -static int iic_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +static int iic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) { struct ibm_iic_private* dev = (struct ibm_iic_private*)(i2c_get_adapdata(adap)); - volatile struct iic_regs *iic = dev->vaddr; + volatile struct iic_regs __iomem *iic = dev->vaddr; int i, ret = 0; DBG2("%d: iic_xfer, %d msg(s)\n", dev->idx, num); @@ -457,13 +571,10 @@ static int iic_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) if (unlikely(msgs[i].len <= 0)){ if (num == 1 && !msgs[0].len){ /* Special case for I2C_SMBUS_QUICK emulation. - * Although this logic is FAR FROM PERFECT, this - * is what previous driver version did. * IBM IIC doesn't support 0-length transactions - * (except bit-banging through IICx_DIRECTCNTL). + * so we have to emulate them using bit-banging. */ - DBG("%d: zero-length msg kludge\n", dev->idx); - return 0; + return iic_smbus_quick(dev, &msgs[0]); } DBG("%d: invalid len %d in msg[%d]\n", dev->idx, msgs[i].len, i); @@ -514,14 +625,8 @@ static u32 iic_func(struct i2c_adapter *adap) return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR; } -static struct i2c_algorithm iic_algo = { - .name = "IBM IIC algorithm", - .id = I2C_ALGO_OCP, +static const struct i2c_algorithm iic_algo = { .master_xfer = iic_xfer, - .smbus_xfer = NULL, - .slave_send = NULL, - .slave_recv = NULL, - .algo_control = NULL, .functionality = iic_func }; @@ -566,16 +671,21 @@ static int __devinit iic_probe(struct ocp_device *ocp){ printk(KERN_WARNING"ibm-iic%d: missing additional data!\n", ocp->def->index); - if (!(dev = kmalloc(sizeof(*dev), GFP_KERNEL))){ + if (!(dev = kzalloc(sizeof(*dev), GFP_KERNEL))) { printk(KERN_CRIT "ibm-iic%d: failed to allocate device data\n", ocp->def->index); return -ENOMEM; } - memset(dev, 0, sizeof(*dev)); dev->idx = ocp->def->index; ocp_set_drvdata(ocp, dev); + if (!request_mem_region(ocp->def->paddr, sizeof(struct iic_regs), + "ibm_iic")) { + ret = -EBUSY; + goto fail1; + } + if (!(dev->vaddr = ioremap(ocp->def->paddr, sizeof(struct iic_regs)))){ printk(KERN_CRIT "ibm-iic%d: failed to ioremap device registers\n", dev->idx); @@ -587,7 +697,7 @@ static int __devinit iic_probe(struct ocp_device *ocp){ dev->irq = iic_force_poll ? -1 : ocp->def->irq; if (dev->irq >= 0){ - /* Disable interrupts until we finish intialization, + /* Disable interrupts until we finish initialization, assumes level-sensitive IRQ setup... */ iic_interrupt_mode(dev, 0); @@ -619,7 +729,8 @@ static int __devinit iic_probe(struct ocp_device *ocp){ adap = &dev->adap; strcpy(adap->name, "IBM IIC"); i2c_set_adapdata(adap, dev); - adap->id = I2C_HW_OCP | iic_algo.id; + adap->id = I2C_HW_OCP; + adap->class = I2C_CLASS_HWMON; adap->algo = &iic_algo; adap->client_register = NULL; adap->client_unregister = NULL; @@ -643,9 +754,11 @@ fail: free_irq(dev->irq, dev); } - iounmap((void*)dev->vaddr); + iounmap(dev->vaddr); fail2: - ocp_set_drvdata(ocp, 0); + release_mem_region(ocp->def->paddr, sizeof(struct iic_regs)); +fail1: + ocp_set_drvdata(ocp, NULL); kfree(dev); return ret; } @@ -671,7 +784,8 @@ static void __devexit iic_remove(struct ocp_device *ocp) iic_interrupt_mode(dev, 0); free_irq(dev->irq, dev); } - iounmap((void*)dev->vaddr); + iounmap(dev->vaddr); + release_mem_region(ocp->def->paddr, sizeof(struct iic_regs)); kfree(dev); } }