From: Marek Szyprowski <m.szyprowski@samsung.com>
Date: Tue, 11 Sep 2018 06:49:39 +0000 (+0200)
Subject: serial: samsung: Enable baud clock for UART reset procedure in resume
X-Git-Tag: submit/tizen/20190329.020226~141
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=e2faacf9e53376b72a10118d886224ab06dd3f54;p=platform%2Fkernel%2Flinux-exynos.git

serial: samsung: Enable baud clock for UART reset procedure in resume

Ensure that baud clock is also enabled for UART reset in driver resume.
On Exynos5433 SoC this is needed to avoid external abort in UART register
writes.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Change-Id: I2987842ea1b38582bdbceb9ffab3ed1a3b1cbfd2
---

diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
index 1b454cb9864b..a4c3e275380d 100644
--- a/drivers/tty/serial/samsung.c
+++ b/drivers/tty/serial/samsung.c
@@ -1922,7 +1922,11 @@ static int s3c24xx_serial_resume(struct device *dev)
 
 	if (port) {
 		clk_prepare_enable(ourport->clk);
+		if (!IS_ERR(ourport->baudclk))
+			clk_prepare_enable(ourport->baudclk);
 		s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));
+		if (!IS_ERR(ourport->baudclk))
+			clk_disable_unprepare(ourport->baudclk);
 		clk_disable_unprepare(ourport->clk);
 
 		uart_resume_port(&s3c24xx_uart_drv, port);
@@ -1945,7 +1949,11 @@ static int s3c24xx_serial_resume_noirq(struct device *dev)
 			if (rx_enabled(port))
 				uintm &= ~S3C64XX_UINTM_RXD_MSK;
 			clk_prepare_enable(ourport->clk);
+			if (!IS_ERR(ourport->baudclk))
+				clk_prepare_enable(ourport->baudclk);
 			wr_regl(port, S3C64XX_UINTM, uintm);
+			if (!IS_ERR(ourport->baudclk))
+				clk_disable_unprepare(ourport->baudclk);
 			clk_disable_unprepare(ourport->clk);
 		}
 	}