*
* Support for the IIC peripheral on IBM PPC 4xx
*
- * Copyright (c) 2003 Zultys Technologies.
+ * Copyright (c) 2003, 2004 Zultys Technologies.
* Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
*
* Based on original work by
#include "i2c-ibm_iic.h"
-#define DRIVER_VERSION "2.0"
+#define DRIVER_VERSION "2.1"
MODULE_DESCRIPTION("IBM IIC driver v" DRIVER_VERSION);
MODULE_LICENSE("GPL");
#endif
#if DBG_LEVEL > 0
-# define DBG(x...) printk(KERN_DEBUG "ibm-iic" ##x)
+# define DBG(f,x...) printk(KERN_DEBUG "ibm-iic" f, ##x)
#else
-# define DBG(x...) ((void)0)
+# define DBG(f,x...) ((void)0)
#endif
#if DBG_LEVEL > 1
-# define DBG2(x...) DBG( ##x )
+# define DBG2(f,x...) DBG(f, ##x)
#else
-# define DBG2(x...) ((void)0)
+# define DBG2(f,x...) ((void)0)
#endif
#if DBG_LEVEL > 2
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)
{
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 *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* 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
*/
}
for (i = 0; i < num; ++i){
if (unlikely(msgs[i].len <= 0)){
+ if (num == 1 && !msgs[0].len){
+ /* Special case for I2C_SMBUS_QUICK emulation.
+ * IBM IIC doesn't support 0-length transactions
+ * so we have to emulate them using bit-banging.
+ */
+ return iic_smbus_quick(dev, &msgs[0]);
+ }
DBG("%d: invalid len %d in msg[%d]\n", dev->idx,
msgs[i].len, i);
return -EINVAL;
struct ibm_iic_private* dev;
struct i2c_adapter* adap;
+ struct ocp_func_iic_data* iic_data = ocp->def->additions;
int ret;
- bd_t* bd = (bd_t*)&__res;
+ if (!iic_data)
+ printk(KERN_WARNING"ibm-iic%d: missing additional data!\n",
+ ocp->def->index);
+
if (!(dev = kmalloc(sizeof(*dev), GFP_KERNEL))){
- printk(KERN_CRIT "ibm-iic: failed to allocate device data\n");
+ 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->num;
+ dev->idx = ocp->def->index;
ocp_set_drvdata(ocp, dev);
- if (!(dev->vaddr = ioremap(ocp->paddr, sizeof(struct iic_regs)))){
+ 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);
ret = -ENXIO;
init_waitqueue_head(&dev->wq);
- dev->irq = iic_force_poll ? -1 : ocp->irq;
+ dev->irq = iic_force_poll ? -1 : ocp->def->irq;
if (dev->irq >= 0){
/* Disable interrupts until we finish intialization,
assumes level-sensitive IRQ setup...
dev->idx);
/* Board specific settings */
- BUG_ON(dev->idx >= sizeof(bd->bi_iic_fast) / sizeof(bd->bi_iic_fast[0]));
- dev->fast_mode = iic_force_fast ? 1 : bd->bi_iic_fast[dev->idx];
+ dev->fast_mode = iic_force_fast ? 1 : (iic_data ? iic_data->fast_mode : 0);
/* clckdiv is the same for *all* IIC interfaces,
* but I'd rather make a copy than introduce another global. --ebs
*/
- dev->clckdiv = iic_clckdiv(bd->bi_opb_busfreq);
+ dev->clckdiv = iic_clckdiv(ocp_sys_info.opb_bus_freq);
DBG("%d: clckdiv = %d\n", dev->idx, dev->clckdiv);
/* Initialize IIC interface */
static struct ocp_device_id ibm_iic_ids[] __devinitdata =
{
- { .vendor = OCP_VENDOR_IBM, .device = OCP_FUNC_IIC },
+ { .vendor = OCP_VENDOR_IBM, .function = OCP_FUNC_IIC },
{ .vendor = OCP_VENDOR_INVALID }
};
static struct ocp_driver ibm_iic_driver =
{
- .name = "ocp_iic",
+ .name = "iic",
.id_table = ibm_iic_ids,
.probe = iic_probe,
.remove = __devexit_p(iic_remove),
static int __init iic_init(void)
{
printk(KERN_INFO "IBM IIC driver v" DRIVER_VERSION "\n");
- return ocp_module_init(&ibm_iic_driver);
+ return ocp_register_driver(&ibm_iic_driver);
}
static void __exit iic_exit(void)
git://git.onelab.eu / linux-2.6.git / blobdiff