i2c: mpc: report correct I2C error return codes

This patch enforces correct I2C error returned codes from Freescale's
MPC i2c bus driver, allowing for proper user-space/kernel error
handling.

Signed-off-by: Danielle Costantino <danielle.costantino@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c
index 0edf630b099a094f4a332a5ba4ce5c2fc973c2f6..4c5d7d92b9fe6c11b1f00a3e17dbf3f0b1168340 100644 (file)
--- a/drivers/i2c/busses/i2c-mpc.c
+++ b/drivers/i2c/busses/i2c-mpc.c
@@ -124,7 +124,7 @@ static void mpc_i2c_fixup(struct mpc_i2c *i2c)
 static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing)
 {
        unsigned long orig_jiffies = jiffies;
-       u32 x;
+       u32 cmd_err;
        int result = 0;
 
        if (!i2c->irq) {
@@ -133,11 +133,11 @@ static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing)
                        if (time_after(jiffies, orig_jiffies + timeout)) {
                                dev_dbg(i2c->dev, "timeout\n");
                                writeccr(i2c, 0);
-                               result = -EIO;
+                               result = -ETIMEDOUT;
                                break;
                        }
                }
-               x = readb(i2c->base + MPC_I2C_SR);
+               cmd_err = readb(i2c->base + MPC_I2C_SR);
                writeb(0, i2c->base + MPC_I2C_SR);
        } else {
                /* Interrupt mode */
@@ -150,28 +150,28 @@ static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing)
                        result = -ETIMEDOUT;
                }
 
-               x = i2c->interrupt;
+               cmd_err = i2c->interrupt;
                i2c->interrupt = 0;
        }
 
        if (result < 0)
                return result;
 
-       if (!(x & CSR_MCF)) {
+       if (!(cmd_err & CSR_MCF)) {
                dev_dbg(i2c->dev, "unfinished\n");
                return -EIO;
        }
 
-       if (x & CSR_MAL) {
+       if (cmd_err & CSR_MAL) {
                dev_dbg(i2c->dev, "MAL\n");
-               return -EIO;
+               return -EAGAIN;
        }
 
-       if (writing && (x & CSR_RXAK)) {
+       if (writing && (cmd_err & CSR_RXAK)) {
                dev_dbg(i2c->dev, "No RXAK\n");
                /* generate stop */
                writeccr(i2c, CCR_MEN);
-               return -EIO;
+               return -ENXIO;
        }
        return 0;
 }