[ARM] 3237/1: PXA I2C driver updates

Patch from Richard Purdie

This patch adds a check to see if the pxa i2c interface is enabled
before allowing it to be used and resets it if found to be disabled.
This automatically restores the interface if the device has been
suspended and resumed without causing any suspend/resume call ordering
issues.

The patch also fixes a build warning and adds an appropriate module
licence (the module is gpl according to the header).

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index 70f7ab829d36..86e2234faf80 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -899,6 +899,12 @@ static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num
         struct pxa_i2c *i2c = adap->algo_data;
         int ret, i;
 
+        /* If the I2C controller is disabled we need to reset it (probably due
+           to a suspend/resume destroying state). We do this here as we can then
+           avoid worrying about resuming the controller before its users. */
+        if (!(ICR & ICR_IUE))
+                i2c_pxa_reset(i2c);
+
         for (i = adap->retries; i >= 0; i--) {
                 ret = i2c_pxa_do_xfer(i2c, msgs, num);
                 if (ret != I2C_RETRY)
@@ -939,7 +945,9 @@ static struct pxa_i2c i2c_pxa = {
 static int i2c_pxa_probe(struct platform_device *dev)
 {
         struct pxa_i2c *i2c = &i2c_pxa;
+#ifdef CONFIG_I2C_PXA_SLAVE
         struct i2c_pxa_platform_data *plat = dev->dev.platform_data;
+#endif
         int ret;
 
 #ifdef CONFIG_PXA27x
@@ -1024,5 +1032,7 @@ static void i2c_adap_pxa_exit(void)
         return platform_driver_unregister(&i2c_pxa_driver);
 }
 
+MODULE_LICENSE("GPL");
+
 module_init(i2c_adap_pxa_init);
 module_exit(i2c_adap_pxa_exit);