spi/tegra: add clk_prepare/clk_unprepare

Use clk_prepare/clk_unprepare as required by the generic clk framework.

Cc: grant.likely@secretlab.ca
cc: spi-devel-general@lists.sourceforge.net
Signed-off-by: NPrashant Gaikwad <pgaikwad@nvidia.com>
Signed-off-by: NStephen Warren <swarren@nvidia.com>

drivers/spi/spi-tegra.c

@@ -261,7 +261,7 @@ static void spi_tegra_start_transfer(struct spi_device *spi,
 		clk_set_rate(tspi->clk, speed);
 
 	if (tspi->cur_speed == 0)
-		clk_enable(tspi->clk);
+		clk_prepare_enable(tspi->clk);
 
 	tspi->cur_speed = speed;
 
@@ -373,7 +373,7 @@ static void tegra_spi_rx_dma_complete(struct tegra_dma_req *req)
 			spi = m->state;
 			spi_tegra_start_message(spi, m);
 		} else {
-			clk_disable(tspi->clk);
+			clk_disable_unprepare(tspi->clk);
 			tspi->cur_speed = 0;
 		}
 	}