drm/amdgpu: Use a single loop

In smu_v11_0_i2c_transmit() use a single loop to
transmit bytes, instead of two nested loops.

Cc: Alexander Deucher <Alexander.Deucher@amd.com>
Cc: Andrey Grodzovsky <Andrey.Grodzovsky@amd.com>
Signed-off-by: Luben Tuikov <luben.tuikov@amd.com>
Reviewed-by: Alexander Deucher <Alexander.Deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/smu_v11_0_i2c.c

@@ -243,18 +243,27 @@ static uint32_t smu_v11_0_i2c_transmit(struct i2c_adapter *control,
 	/* Clear status bits */
 	smu_v11_0_i2c_clear_status(control);
 
-
 	timeout_counter = jiffies + msecs_to_jiffies(20);
 
 	while (numbytes > 0) {
 		reg = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_STATUS);
-		if (REG_GET_FIELD(reg, CKSVII2C_IC_STATUS, TFNF)) {
-			do {
-				reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, DAT, data[bytes_sent]);
+		if (!REG_GET_FIELD(reg, CKSVII2C_IC_STATUS, TFNF)) {
+			/*
+			 * We waited for too long for the transmission
+			 * FIFO to become not-full.  Exit the loop
+			 * with error.
+			 */
+			if (time_after(jiffies, timeout_counter)) {
+				ret |= I2C_SW_TIMEOUT;
+				goto Err;
+			}
+		} else {
+			reg = REG_SET_FIELD(reg, CKSVII2C_IC_DATA_CMD, DAT,
+					    data[bytes_sent]);
 
-				/* Final message, final byte, must
-				 * generate a STOP, to release the
-				 * bus, i.e. don't hold SCL low.
+			/* Final message, final byte, must generate a
+			 * STOP to release the bus, i.e. don't hold
+			 * SCL low.
 			 */
 			if (numbytes == 1 && i2c_flag & I2C_M_STOP)
 				reg = REG_SET_FIELD(reg,
@@ -273,19 +282,6 @@ static uint32_t smu_v11_0_i2c_transmit(struct i2c_adapter *control,
 			/* Record that the bytes were transmitted */
 			bytes_sent++;
 			numbytes--;
-
-				reg = RREG32_SOC15(SMUIO, 0, mmCKSVII2C_IC_STATUS);
-
-			} while (numbytes &&  REG_GET_FIELD(reg, CKSVII2C_IC_STATUS, TFNF));
-		}
-
-		/*
-		 * We waited too long for the transmission FIFO to become not-full.
-		 * Exit the loop with error.
-		 */
-		if (time_after(jiffies, timeout_counter)) {
-			ret |= I2C_SW_TIMEOUT;
-			goto Err;
 		}
 	}