linux-samsung-soc.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v4] phy: samsung: Use readl_poll_timeout function
@ 2020-07-13  7:42 Anand Moon
  2020-07-16  5:50 ` Vinod Koul
  2020-07-20  7:50 ` Krzysztof Kozlowski
  0 siblings, 2 replies; 5+ messages in thread
From: Anand Moon @ 2020-07-13  7:42 UTC (permalink / raw)
  To: linux-arm-kernel, linux-usb, linux-samsung-soc, linux-kernel
  Cc: Kishon Vijay Abraham I, Vinod Koul, Kukjin Kim,
	Krzysztof Kozlowski, Marek Szyprowski

Instead of a busy waiting while loop using udelay
use readl_poll_timeout function to check the condition
is met or timeout occurs in crport_handshake function.
readl_poll_timeout is called in non atomic context so
it safe to sleep until the condition is met.

Fixes: d8c80bb3b55b ("phy: exynos5-usbdrd: Calibrate LOS levels for exynos5420/5800")
Signed-off-by: Anand Moon <linux.amoon@gmail.com>
---
Changes v4:
Rebased on to of patch [0] https://patchwork.kernel.org/patch/11651673/
--Fix the commit message.
--Fix the error timeout condition for -ETIMEDOUT
---
Changes v3:
--Fix the commit message.
--Drop the variable, used the value directly.
Changes v2:
--used the default timeout values.
--Added missing Fixed tags.
---
 drivers/phy/samsung/phy-exynos5-usbdrd.c | 39 ++++++++----------------
 1 file changed, 12 insertions(+), 27 deletions(-)

diff --git a/drivers/phy/samsung/phy-exynos5-usbdrd.c b/drivers/phy/samsung/phy-exynos5-usbdrd.c
index 7f6279fb4f8f..ad81aa65cdff 100644
--- a/drivers/phy/samsung/phy-exynos5-usbdrd.c
+++ b/drivers/phy/samsung/phy-exynos5-usbdrd.c
@@ -16,6 +16,7 @@
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_device.h>
+#include <linux/iopoll.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
 #include <linux/mutex.h>
@@ -556,41 +557,25 @@ static int exynos5_usbdrd_phy_power_off(struct phy *phy)
 static int crport_handshake(struct exynos5_usbdrd_phy *phy_drd,
 			    u32 val, u32 cmd)
 {
-	u32 usec = 100;
 	unsigned int result;
+	int err;
 
 	writel(val | cmd, phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
 
-	do {
-		result = readl(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1);
-		if (result & PHYREG1_CR_ACK)
-			break;
-
-		udelay(1);
-	} while (usec-- > 0);
-
-	if (!usec) {
-		dev_err(phy_drd->dev,
-			"CRPORT handshake timeout1 (0x%08x)\n", val);
-		return -ETIME;
+	err = readl_poll_timeout(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1,
+			result,	(result & PHYREG1_CR_ACK), 1, 100);
+	if (err == -ETIMEDOUT) {
+		dev_err(phy_drd->dev, "CRPORT handshake timeout1 (0x%08x)\n", val);
+		return err;
 	}
 
-	usec = 100;
-
 	writel(val, phy_drd->reg_phy + EXYNOS5_DRD_PHYREG0);
 
-	do {
-		result = readl(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1);
-		if (!(result & PHYREG1_CR_ACK))
-			break;
-
-		udelay(1);
-	} while (usec-- > 0);
-
-	if (!usec) {
-		dev_err(phy_drd->dev,
-			"CRPORT handshake timeout2 (0x%08x)\n", val);
-		return -ETIME;
+	err = readl_poll_timeout(phy_drd->reg_phy + EXYNOS5_DRD_PHYREG1,
+			result,	!(result & PHYREG1_CR_ACK), 1, 100);
+	if (err == -ETIMEDOUT) {
+		dev_err(phy_drd->dev, "CRPORT handshake timeout2 (0x%08x)\n", val);
+		return err;
 	}
 
 	return 0;
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2020-07-20  8:58 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-13  7:42 [PATCH v4] phy: samsung: Use readl_poll_timeout function Anand Moon
2020-07-16  5:50 ` Vinod Koul
2020-07-16  5:56   ` Anand Moon
2020-07-20  7:50 ` Krzysztof Kozlowski
2020-07-20  8:58   ` Anand Moon

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).