[PATCH] locomo.c: fix missing spin_unlock_irqrestore

[H Hartley Sweeten]

The function locomo_m62332_senddata sends a three byte i2c message to
a M62332 DAC. This entire function is guarded with a spin_lock_irqsave
at the start of the function and a spin_unlock_irqrestore at the end.

As each byte is transferred, the ACK from the DAC is checked. Currently,
If the ACK is missing the function simply returns without the unlock.
It also leaves the i2c bus in an invalid state since the last byte
transferred did not have a "stop" condition and leave the bus idle.

Fix this by adding an exit path using goto.

Signed-off-by: H Hartley Sweeten <hsweeten at visionengravers.com>

---

diff --git a/arch/arm/common/locomo.c b/arch/arm/common/locomo.c
index bd36c77..2f693da 100644
--- a/arch/arm/common/locomo.c
+++ b/arch/arm/common/locomo.c
@@ -1007,7 +1007,7 @@ void locomo_m62332_senddata(struct locomo_dev *ldev, unsigned int dac_data, int
        udelay(DAC_SCL_HIGH_HOLD_TIME); /* 4.7 usec */
        if (locomo_readl(mapbase + LOCOMO_DAC) & LOCOMO_DAC_SDAOEB) {   /* High is error */
                printk(KERN_WARNING "locomo: m62332_senddata Error 1\n");
-               return;
+               goto out;
        }
 
        /* Send Sub address (LSB is channel select) */
@@ -1035,7 +1035,7 @@ void locomo_m62332_senddata(struct locomo_dev *ldev, unsigned int dac_data, int
        udelay(DAC_SCL_HIGH_HOLD_TIME); /* 4.7 usec */
        if (locomo_readl(mapbase + LOCOMO_DAC) & LOCOMO_DAC_SDAOEB) {   /* High is error */
                printk(KERN_WARNING "locomo: m62332_senddata Error 2\n");
-               return;
+               goto out;
        }
 
        /* Send DAC data */
@@ -1060,9 +1060,9 @@ void locomo_m62332_senddata(struct locomo_dev *ldev, unsigned int dac_data, int
        udelay(DAC_SCL_HIGH_HOLD_TIME); /* 4.7 usec */
        if (locomo_readl(mapbase + LOCOMO_DAC) & LOCOMO_DAC_SDAOEB) {   /* High is error */
                printk(KERN_WARNING "locomo: m62332_senddata Error 3\n");
-               return;
        }
 
+out:
        /* stop */
        r = locomo_readl(mapbase + LOCOMO_DAC);
        r &=  ~(LOCOMO_DAC_SCLOEB);