linux-kernel - [PATCH v7 20/34] i2c: tegra: Remove "dma" variable from tegra_i2c_xfer

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Date:   Wed,  9 Sep 2020 01:39:52 +0300
From:   Dmitry Osipenko <digetx@...il.com>
To:     Thierry Reding <thierry.reding@...il.com>,
        Jonathan Hunter <jonathanh@...dia.com>,
        Laxman Dewangan <ldewangan@...dia.com>,
        Wolfram Sang <wsa@...-dreams.de>,
        Michał Mirosław <mirq-linux@...e.qmqm.pl>,
        Andy Shevchenko <andy.shevchenko@...il.com>
Cc:     linux-i2c@...r.kernel.org, linux-tegra@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH v7 20/34] i2c: tegra: Remove "dma" variable from tegra_i2c_xfer_msg()

The "dma" variable of tegra_i2c_xfer_msg() function doesn't bring much in
regards to readability and generation of the code.

Besides readability, it's also not very nice that the is_curr_dma_xfer
is initialized in tegra_i2c_xfer_msg() and then could be overridden by
tegra_i2c_config_fifo_trig(). In a result, the "dma" variable creates
slight confusion since it's not instantly obvious why it's set after
tegra_i2c_config_fifo_trig().

Hence should be better to have the variable removed. This makes code
more consistent.

Signed-off-by: Dmitry Osipenko <digetx@...il.com>
---
 drivers/i2c/busses/i2c-tegra.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 18968302457f..76d3a05b10fc 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -1120,7 +1120,6 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
 	size_t xfer_size;
 	u32 *buffer = NULL;
 	int err = 0;
-	bool dma;
 	u16 xfer_time = 100;
 
 	err = tegra_i2c_flush_fifos(i2c_dev);
@@ -1143,7 +1142,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
 				    i2c_dev->dma_buf &&
 				    !i2c_dev->is_curr_atomic_xfer;
 	tegra_i2c_config_fifo_trig(i2c_dev, xfer_size);
-	dma = i2c_dev->is_curr_dma_xfer;
+
 	/*
 	 * Transfer time in mSec = Total bits / transfer rate
 	 * Total bits = 9 bits per byte (including ACK bit) + Start & stop bits
@@ -1153,7 +1152,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
 
 	int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST;
 	tegra_i2c_unmask_irq(i2c_dev, int_mask);
-	if (dma) {
+	if (i2c_dev->is_curr_dma_xfer) {
 		if (i2c_dev->msg_read) {
 			dma_sync_single_for_device(i2c_dev->dev,
 						   i2c_dev->dma_phys,
@@ -1181,13 +1180,13 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
 				   PACKET_HEADER0_PROTOCOL_I2C) |
 			FIELD_PREP(PACKET_HEADER0_CONT_ID, i2c_dev->cont_id) |
 			FIELD_PREP(PACKET_HEADER0_PACKET_ID, 1);
-	if (dma && !i2c_dev->msg_read)
+	if (i2c_dev->is_curr_dma_xfer && !i2c_dev->msg_read)
 		*buffer++ = packet_header;
 	else
 		i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
 
 	packet_header = msg->len - 1;
-	if (dma && !i2c_dev->msg_read)
+	if (i2c_dev->is_curr_dma_xfer && !i2c_dev->msg_read)
 		*buffer++ = packet_header;
 	else
 		i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
@@ -1207,13 +1206,13 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
 		packet_header |= I2C_HEADER_CONT_ON_NAK;
 	if (msg->flags & I2C_M_RD)
 		packet_header |= I2C_HEADER_READ;
-	if (dma && !i2c_dev->msg_read)
+	if (i2c_dev->is_curr_dma_xfer && !i2c_dev->msg_read)
 		*buffer++ = packet_header;
 	else
 		i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
 
 	if (!i2c_dev->msg_read) {
-		if (dma) {
+		if (i2c_dev->is_curr_dma_xfer) {
 			memcpy(buffer, msg->buf, msg->len);
 			dma_sync_single_for_device(i2c_dev->dev,
 						   i2c_dev->dma_phys,
@@ -1233,7 +1232,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
 
 	if (i2c_dev->hw->has_per_pkt_xfer_complete_irq)
 		int_mask |= I2C_INT_PACKET_XFER_COMPLETE;
-	if (!dma) {
+	if (!i2c_dev->is_curr_dma_xfer) {
 		if (msg->flags & I2C_M_RD)
 			int_mask |= I2C_INT_RX_FIFO_DATA_REQ;
 		else if (i2c_dev->msg_buf_remaining)
@@ -1244,7 +1243,7 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
 	dev_dbg(i2c_dev->dev, "unmasked irq: %02x\n",
 		i2c_readl(i2c_dev, I2C_INT_MASK));
 
-	if (dma) {
+	if (i2c_dev->is_curr_dma_xfer) {
 		time_left = tegra_i2c_wait_completion_timeout(
 				i2c_dev, &i2c_dev->dma_complete, xfer_time);
 
-- 
2.27.0