[PATCH AUTOSEL 4.14 049/170] i2c: sh_mobile: add support for r8a77990 (R-Car E3)

[PATCH AUTOSEL 4.14 049/170] i2c: sh_mobile: add support for r8a77990 (R-Car E3)

[Sasha Levin]

From: Simon Horman <horms+renesas@verge.net.au>

[ Upstream commit 5eb316e636eb298c204f5b368526d4480b63c0ba ]

Add support for the IIC code for the r8a77990 (R-Car E3).

It is not considered compatible with existing fallback bindings
due to the documented absence of automatic transmission registers.

These registers are currently not used by the driver and
thus the provides the same behaviour for "renesas,iic-r8a77990" and
"renesas,rcar-gen3-iic". The point of declaring incompatibility is
to allow for automatic transmission register support to be added to
"renesas,iic-r8a77990" and "renesas,rcar-gen3-iic" in future.

Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/i2c/busses/i2c-sh_mobile.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index 6f2aaeb7c4fa..338344e76e02 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -836,6 +836,7 @@ static const struct of_device_id sh_mobile_i2c_dt_ids[] = {
 	{ .compatible = "renesas,rcar-gen2-iic", .data = &fast_clock_dt_config },
 	{ .compatible = "renesas,iic-r8a7795", .data = &fast_clock_dt_config },
 	{ .compatible = "renesas,rcar-gen3-iic", .data = &fast_clock_dt_config },
+	{ .compatible = "renesas,iic-r8a77990", .data = &fast_clock_dt_config },
 	{ .compatible = "renesas,iic-sh73a0", .data = &fast_clock_dt_config },
 	{ .compatible = "renesas,rmobile-iic", .data = &default_dt_config },
 	{},
-- 
2.19.1

[PATCH AUTOSEL 4.14 090/170] i2c-axxia: check for error conditions first

[Sasha Levin]

From: "Adamski, Krzysztof (Nokia - PL/Wroclaw)" <krzysztof.adamski@nokia.com>

[ Upstream commit 4f5c85fe3a60ace555d09898166af372547f97fc ]

It was observed that when using seqentional mode contrary to the
documentation, the SS bit (which is supposed to only be set if
automatic/sequence command completed normally), is sometimes set
together with NA (NAK in address phase) causing transfer to falsely be
considered successful.

My assumption is that this does not happen during manual mode since the
controller is stopping its work the moment it sets NA/ND bit in status
register. This is not the case in Automatic/Sequentional mode where it
is still working to send STOP condition and the actual status we get
depends on the time when the ISR is run.

This patch changes the order of checking status bits in ISR - error
conditions are checked first and only if none of them occurred, the
transfer may be considered successful. This is required to introduce
using of sequentional mode in next patch.

Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/i2c/busses/i2c-axxia.c | 32 ++++++++++++++++----------------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/drivers/i2c/busses/i2c-axxia.c b/drivers/i2c/busses/i2c-axxia.c
index deea13838648..30d80ce0bde3 100644
--- a/drivers/i2c/busses/i2c-axxia.c
+++ b/drivers/i2c/busses/i2c-axxia.c
@@ -296,22 +296,7 @@ static irqreturn_t axxia_i2c_isr(int irq, void *_dev)
 			i2c_int_disable(idev, MST_STATUS_TFL);
 	}
 
-	if (status & MST_STATUS_SCC) {
-		/* Stop completed */
-		i2c_int_disable(idev, ~MST_STATUS_TSS);
-		complete(&idev->msg_complete);
-	} else if (status & MST_STATUS_SNS) {
-		/* Transfer done */
-		i2c_int_disable(idev, ~MST_STATUS_TSS);
-		if (i2c_m_rd(idev->msg) && idev->msg_xfrd < idev->msg->len)
-			axxia_i2c_empty_rx_fifo(idev);
-		complete(&idev->msg_complete);
-	} else if (status & MST_STATUS_TSS) {
-		/* Transfer timeout */
-		idev->msg_err = -ETIMEDOUT;
-		i2c_int_disable(idev, ~MST_STATUS_TSS);
-		complete(&idev->msg_complete);
-	} else if (unlikely(status & MST_STATUS_ERR)) {
+	if (unlikely(status & MST_STATUS_ERR)) {
 		/* Transfer error */
 		i2c_int_disable(idev, ~0);
 		if (status & MST_STATUS_AL)
@@ -328,6 +313,21 @@ static irqreturn_t axxia_i2c_isr(int irq, void *_dev)
 			readl(idev->base + MST_TX_BYTES_XFRD),
 			readl(idev->base + MST_TX_XFER));
 		complete(&idev->msg_complete);
+	} else if (status & MST_STATUS_SCC) {
+		/* Stop completed */
+		i2c_int_disable(idev, ~MST_STATUS_TSS);
+		complete(&idev->msg_complete);
+	} else if (status & MST_STATUS_SNS) {
+		/* Transfer done */
+		i2c_int_disable(idev, ~MST_STATUS_TSS);
+		if (i2c_m_rd(idev->msg) && idev->msg_xfrd < idev->msg->len)
+			axxia_i2c_empty_rx_fifo(idev);
+		complete(&idev->msg_complete);
+	} else if (status & MST_STATUS_TSS) {
+		/* Transfer timeout */
+		idev->msg_err = -ETIMEDOUT;
+		i2c_int_disable(idev, ~MST_STATUS_TSS);
+		complete(&idev->msg_complete);
 	}
 
 out:
-- 
2.19.1