i2c: pxa: add support for SCCB devices

Add support for SCCB by implementing I2C_M_IGNORE_NAK and I2C_M_STOP
flags and advertising functionality flag I2C_FUNC_PROTOCOL_MANGLING.

Also fixed missing functionality flag I2C_FUNC_NOSTART.

Signed-off-by: Petr Cvek <petr.cvek@tul.cz>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

1 files changed, 12 insertions, 7 deletions

diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
index be671f7a0e06..f80df8f84609 100644
--- a/drivers/i2c/busses/i2c-pxa.c
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -885,7 +885,9 @@ static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
                 return; /* ignore */
         }
 
-        if (isr & ISR_BED) {
+        if ((isr & ISR_BED) &&
+                (!((i2c->msg->flags & I2C_M_IGNORE_NAK) &&
+                        (isr & ISR_ACKNAK)))) {
                 int ret = BUS_ERROR;
 
                 /*
@@ -919,12 +921,14 @@ static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
                 icr |= ICR_ALDIE | ICR_TB;
 
                 /*
-                 * If this is the last byte of the last message, send
-                 * a STOP.
+                 * If this is the last byte of the last message or last byte
+                 * of any message with I2C_M_STOP (e.g. SCCB), send a STOP.
                  */
-                if (i2c->msg_ptr == i2c->msg->len &&
-                    i2c->msg_idx == i2c->msg_num - 1)
-                        icr |= ICR_STOP;
+                if ((i2c->msg_ptr == i2c->msg->len) &&
+                        ((i2c->msg->flags & I2C_M_STOP) ||
+                        (i2c->msg_idx == i2c->msg_num - 1)))
+                                icr |= ICR_STOP;
+
         } else if (i2c->msg_idx < i2c->msg_num - 1) {
                 /*
                  * Next segment of the message.
@@ -1071,7 +1075,8 @@ static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num
 
 static u32 i2c_pxa_functionality(struct i2c_adapter *adap)
 {
-        return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+        return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
+                I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART;
 }
 
 static const struct i2c_algorithm i2c_pxa_algorithm = {