1 files changed, 78 insertions, 90 deletions

diff --git a/drivers/i2c/busses/i2c-bfin-twi.c b/drivers/i2c/busses/i2c-bfin-twi.c
index f1e14dd590c9..fb26e5c67515 100644
--- a/drivers/i2c/busses/i2c-bfin-twi.c
+++ b/drivers/i2c/busses/i2c-bfin-twi.c
@@ -25,8 +25,6 @@
 #include <asm/portmux.h>
 #include <asm/irq.h>
 
-#define POLL_TIMEOUT       (2 * HZ)
-
 /* SMBus mode*/
 #define TWI_I2C_MODE_STANDARD           1
 #define TWI_I2C_MODE_STANDARDSUB        2
@@ -44,8 +42,6 @@ struct bfin_twi_iface {
         int                     cur_mode;
         int                     manual_stop;
         int                     result;
-        int                     timeout_count;
-        struct timer_list       timeout_timer;
         struct i2c_adapter      adap;
         struct completion       complete;
         struct i2c_msg          *pmsg;
@@ -85,14 +81,15 @@ static const u16 pin_req[2][3] = {
         {P_TWI1_SCL, P_TWI1_SDA, 0},
 };
 
-static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface)
+static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface,
+                                        unsigned short twi_int_status)
 {
-        unsigned short twi_int_status = read_INT_STAT(iface);
         unsigned short mast_stat = read_MASTER_STAT(iface);
 
         if (twi_int_status & XMTSERV) {
                 /* Transmit next data */
                 if (iface->writeNum > 0) {
+                        SSYNC();
                         write_XMT_DATA8(iface, *(iface->transPtr++));
                         iface->writeNum--;
                 }
@@ -114,10 +111,6 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface)
                                 write_MASTER_CTL(iface,
                                         (read_MASTER_CTL(iface) | RSTART) & ~MDIR);
                 }
-                SSYNC();
-                /* Clear status */
-                write_INT_STAT(iface, XMTSERV);
-                SSYNC();
         }
         if (twi_int_status & RCVSERV) {
                 if (iface->readNum > 0) {
@@ -139,7 +132,6 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface)
                 } else if (iface->manual_stop) {
                         write_MASTER_CTL(iface,
                                 read_MASTER_CTL(iface) | STOP);
-                        SSYNC();
                 } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
                            iface->cur_msg + 1 < iface->msg_num) {
                         if (iface->pmsg[iface->cur_msg + 1].flags & I2C_M_RD)
@@ -148,44 +140,37 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface)
                         else
                                 write_MASTER_CTL(iface,
                                         (read_MASTER_CTL(iface) | RSTART) & ~MDIR);
-                        SSYNC();
                 }
-                /* Clear interrupt source */
-                write_INT_STAT(iface, RCVSERV);
-                SSYNC();
         }
         if (twi_int_status & MERR) {
-                write_INT_STAT(iface, MERR);
                 write_INT_MASK(iface, 0);
                 write_MASTER_STAT(iface, 0x3e);
                 write_MASTER_CTL(iface, 0);
-                SSYNC();
                 iface->result = -EIO;
-                /* if both err and complete int stats are set, return proper
-                 * results.
+
+                if (mast_stat & LOSTARB)
+                        dev_dbg(&iface->adap.dev, "Lost Arbitration\n");
+                if (mast_stat & ANAK)
+                        dev_dbg(&iface->adap.dev, "Address Not Acknowledged\n");
+                if (mast_stat & DNAK)
+                        dev_dbg(&iface->adap.dev, "Data Not Acknowledged\n");
+                if (mast_stat & BUFRDERR)
+                        dev_dbg(&iface->adap.dev, "Buffer Read Error\n");
+                if (mast_stat & BUFWRERR)
+                        dev_dbg(&iface->adap.dev, "Buffer Write Error\n");
+
+                /* If it is a quick transfer, only address without data,
+                 * not an err, return 1.
                  */
-                if (twi_int_status & MCOMP) {
-                        write_INT_STAT(iface, MCOMP);
-                        write_INT_MASK(iface, 0);
-                        write_MASTER_CTL(iface, 0);
-                        SSYNC();
-                        /* If it is a quick transfer, only address bug no data,
-                         * not an err, return 1.
-                         */
-                        if (iface->writeNum == 0 && (mast_stat & BUFRDERR))
-                                iface->result = 1;
-                        /* If address not acknowledged return -1,
-                         * else return 0.
-                         */
-                        else if (!(mast_stat & ANAK))
-                                iface->result = 0;
-                }
+                if (iface->cur_mode == TWI_I2C_MODE_STANDARD &&
+                        iface->transPtr == NULL &&
+                        (twi_int_status & MCOMP) && (mast_stat & DNAK))
+                        iface->result = 1;
+
                 complete(&iface->complete);
                 return;
         }
         if (twi_int_status & MCOMP) {
-                write_INT_STAT(iface, MCOMP);
-                SSYNC();
                 if (iface->cur_mode == TWI_I2C_MODE_COMBINED) {
                         if (iface->readNum == 0) {
                                 /* set the read number to 1 and ask for manual
@@ -207,7 +192,6 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface)
                         /* remove restart bit and enable master receive */
                         write_MASTER_CTL(iface,
                                 read_MASTER_CTL(iface) & ~RSTART);
-                        SSYNC();
                 } else if (iface->cur_mode == TWI_I2C_MODE_REPEAT &&
                                 iface->cur_msg+1 < iface->msg_num) {
                         iface->cur_msg++;
@@ -226,7 +210,6 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface)
                                         write_XMT_DATA8(iface,
                                                 *(iface->transPtr++));
                                         iface->writeNum--;
-                                        SSYNC();
                                 }
                         }
 
@@ -244,15 +227,13 @@ static void bfin_twi_handle_interrupt(struct bfin_twi_iface *iface)
                         /* remove restart bit and enable master receive */
                         write_MASTER_CTL(iface,
                                 read_MASTER_CTL(iface) & ~RSTART);
-                        SSYNC();
                 } else {
                         iface->result = 1;
                         write_INT_MASK(iface, 0);
                         write_MASTER_CTL(iface, 0);
-                        SSYNC();
-                        complete(&iface->complete);
                 }
         }
+        complete(&iface->complete);
 }
 
 /* Interrupt handler */
@@ -260,38 +241,26 @@ static irqreturn_t bfin_twi_interrupt_entry(int irq, void *dev_id)
 {
         struct bfin_twi_iface *iface = dev_id;
         unsigned long flags;
+        unsigned short twi_int_status;
 
         spin_lock_irqsave(&iface->lock, flags);
-        del_timer(&iface->timeout_timer);
-        bfin_twi_handle_interrupt(iface);
-        spin_unlock_irqrestore(&iface->lock, flags);
-        return IRQ_HANDLED;
-}
-
-static void bfin_twi_timeout(unsigned long data)
-{
-        struct bfin_twi_iface *iface = (struct bfin_twi_iface *)data;
-        unsigned long flags;
-
-        spin_lock_irqsave(&iface->lock, flags);
-        bfin_twi_handle_interrupt(iface);
-        if (iface->result == 0) {
-                iface->timeout_count--;
-                if (iface->timeout_count > 0) {
-                        iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
-                        add_timer(&iface->timeout_timer);
-                } else {
-                        iface->result = -1;
-                        complete(&iface->complete);
-                }
+        while (1) {
+                twi_int_status = read_INT_STAT(iface);
+                if (!twi_int_status)
+                        break;
+                /* Clear interrupt status */
+                write_INT_STAT(iface, twi_int_status);
+                bfin_twi_handle_interrupt(iface, twi_int_status);
+                SSYNC();
         }
         spin_unlock_irqrestore(&iface->lock, flags);
+        return IRQ_HANDLED;
 }
 
 /*
- * Generic i2c master transfer entrypoint
+ * One i2c master transfer
  */
-static int bfin_twi_master_xfer(struct i2c_adapter *adap,
+static int bfin_twi_do_master_xfer(struct i2c_adapter *adap,
                                 struct i2c_msg *msgs, int num)
 {
         struct bfin_twi_iface *iface = adap->algo_data;
@@ -319,7 +288,6 @@ static int bfin_twi_master_xfer(struct i2c_adapter *adap,
         iface->transPtr = pmsg->buf;
         iface->writeNum = iface->readNum = pmsg->len;
         iface->result = 0;
-        iface->timeout_count = 10;
         init_completion(&(iface->complete));
         /* Set Transmit device address */
         write_MASTER_ADDR(iface, pmsg->addr);
@@ -358,30 +326,41 @@ static int bfin_twi_master_xfer(struct i2c_adapter *adap,
                 iface->manual_stop = 1;
         }
 
-        iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
-        add_timer(&iface->timeout_timer);
-
         /* Master enable */
         write_MASTER_CTL(iface, read_MASTER_CTL(iface) | MEN |
                 ((iface->read_write == I2C_SMBUS_READ) ? MDIR : 0) |
                 ((CONFIG_I2C_BLACKFIN_TWI_CLK_KHZ > 100) ? FAST : 0));
         SSYNC();
 
-        wait_for_completion(&iface->complete);
-
-        rc = iface->result;
+        while (!iface->result) {
+                if (!wait_for_completion_timeout(&iface->complete,
+                        adap->timeout)) {
+                        iface->result = -1;
+                        dev_err(&adap->dev, "master transfer timeout\n");
+                }
+        }
 
-        if (rc == 1)
-                return num;
+        if (iface->result == 1)
+                rc = iface->cur_msg + 1;
         else
-                return rc;
+                rc = iface->result;
+
+        return rc;
 }
 
 /*
- * SMBus type transfer entrypoint
+ * Generic i2c master transfer entrypoint
  */
+static int bfin_twi_master_xfer(struct i2c_adapter *adap,
+                                struct i2c_msg *msgs, int num)
+{
+        return bfin_twi_do_master_xfer(adap, msgs, num);
+}
 
-int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
+/*
+ * One I2C SMBus transfer
+ */
+int bfin_twi_do_smbus_xfer(struct i2c_adapter *adap, u16 addr,
                         unsigned short flags, char read_write,
                         u8 command, int size, union i2c_smbus_data *data)
 {
@@ -469,7 +448,6 @@ int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
         iface->manual_stop = 0;
         iface->read_write = read_write;
         iface->command = command;
-        iface->timeout_count = 10;
         init_completion(&(iface->complete));
 
         /* FIFO Initiation. Data in FIFO should be discarded before
@@ -486,9 +464,6 @@ int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
         write_MASTER_ADDR(iface, addr);
         SSYNC();
 
-        iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
-        add_timer(&iface->timeout_timer);
-
         switch (iface->cur_mode) {
         case TWI_I2C_MODE_STANDARDSUB:
                 write_XMT_DATA8(iface, iface->command);
@@ -550,10 +525,8 @@ int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
                                 else if (iface->readNum > 255) {
                                         write_MASTER_CTL(iface, 0xff << 6);
                                         iface->manual_stop = 1;
-                                } else {
-                                        del_timer(&iface->timeout_timer);
+                                } else
                                         break;
-                                }
                         }
                 }
                 write_INT_MASK(iface, MCOMP | MERR |
@@ -569,7 +542,13 @@ int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
         }
         SSYNC();
 
-        wait_for_completion(&iface->complete);
+        while (!iface->result) {
+                if (!wait_for_completion_timeout(&iface->complete,
+                        adap->timeout)) {
+                        iface->result = -1;
+                        dev_err(&adap->dev, "smbus transfer timeout\n");
+                }
+        }
 
         rc = (iface->result >= 0) ? 0 : -1;
 
@@ -577,6 +556,17 @@ int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
 }
 
 /*
+ * Generic I2C SMBus transfer entrypoint
+ */
+int bfin_twi_smbus_xfer(struct i2c_adapter *adap, u16 addr,
+                        unsigned short flags, char read_write,
+                        u8 command, int size, union i2c_smbus_data *data)
+{
+        return bfin_twi_do_smbus_xfer(adap, addr, flags,
+                        read_write, command, size, data);
+}
+
+/*
  * Return what the adapter supports
  */
 static u32 bfin_twi_functionality(struct i2c_adapter *adap)
@@ -667,10 +657,6 @@ static int i2c_bfin_twi_probe(struct platform_device *pdev)
                 goto out_error_no_irq;
         }
 
-        init_timer(&(iface->timeout_timer));
-        iface->timeout_timer.function = bfin_twi_timeout;
-        iface->timeout_timer.data = (unsigned long)iface;
-
         p_adap = &iface->adap;
         p_adap->nr = pdev->id;
         strlcpy(p_adap->name, pdev->name, sizeof(p_adap->name));
@@ -678,6 +664,8 @@ static int i2c_bfin_twi_probe(struct platform_device *pdev)
         p_adap->algo_data = iface;
         p_adap->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
         p_adap->dev.parent = &pdev->dev;
+        p_adap->timeout = 5 * HZ;
+        p_adap->retries = 3;
 
         rc = peripheral_request_list(pin_req[pdev->id], "i2c-bfin-twi");
         if (rc) {