Merge branch 'i2c/for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:

 - the core has now a lockless variant of i2c_smbus_xfer. Some open
   coded versions of this got removed in drivers. This also enables
   proper SCCB support in regmap.

 - locking got a more precise naming. i2c_{un}lock_adapter() had to go,
   and we know use i2c_lock_bus() consistently with flags like
   I2C_LOCK_ROOT_ADAPTER and I2C_LOCK_SEGMENT to avoid ambiguity.

 - the gpio fault injector got a new delicate testcase

 - the bus recovery procedure got fixed to handle the new testcase
   correctly

 - a new quirk flag for controllers not able to handle zero length
   messages together with driver updates to use it

 - new drivers: FSI bus attached I2C masters, GENI I2C controller, Owl
   family S900

 - and a good set of driver improvements and bugfixes

* 'i2c/for-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (77 commits)
  i2c: rcar: implement STOP and REP_START according to docs
  i2c: rcar: refactor private flags
  i2c: core: ACPI: Make acpi_gsb_i2c_read_bytes() check i2c_transfer return value
  i2c: core: ACPI: Properly set status byte to 0 for multi-byte writes
  dt-bindings: i2c: rcar: Add r8a774a1 support
  dt-bindings: i2c: sh_mobile: Add r8a774a1 support
  i2c: imx: Simplify stopped state tracking
  i2c: imx: Fix race condition in dma read
  i2c: pasemi: remove hardcoded bus numbers on smbus
  i2c: designware: Add SPDX license tag
  i2c: designware: Convert to use struct i2c_timings
  i2c: core: Parse SDA hold time from firmware
  i2c: designware-pcidrv: Mark expected switch fall-through
  i2c: amd8111: Mark expected switch fall-through
  i2c: sh_mobile: use core to detect 'no zero length read' quirk
  i2c: xlr: use core to detect 'no zero length' quirk
  i2c: rcar: use core to detect 'no zero length' quirk
  i2c: stu300: use core to detect 'no zero length' quirk
  i2c: pmcmsp: use core to detect 'no zero length' quirk
  i2c: mxs: use core to detect 'no zero length' quirk
  ...

1 files changed, 11 insertions, 12 deletions

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 498c5e891649..c406700789e1 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -421,10 +421,14 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
 			return -EAGAIN;
 		}
 
-		if (for_busy && (temp & I2SR_IBB))
+		if (for_busy && (temp & I2SR_IBB)) {
+			i2c_imx->stopped = 0;
 			break;
-		if (!for_busy && !(temp & I2SR_IBB))
+		}
+		if (!for_busy && !(temp & I2SR_IBB)) {
+			i2c_imx->stopped = 1;
 			break;
+		}
 		if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
 			dev_dbg(&i2c_imx->adapter.dev,
 				"<%s> I2C bus is busy\n", __func__);
@@ -538,7 +542,6 @@ static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
 	result = i2c_imx_bus_busy(i2c_imx, 1);
 	if (result)
 		return result;
-	i2c_imx->stopped = 0;
 
 	temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
 	temp &= ~I2CR_DMAEN;
@@ -567,10 +570,8 @@ static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
 		udelay(i2c_imx->disable_delay);
 	}
 
-	if (!i2c_imx->stopped) {
+	if (!i2c_imx->stopped)
 		i2c_imx_bus_busy(i2c_imx, 0);
-		i2c_imx->stopped = 1;
-	}
 
 	/* Disable I2C controller */
 	temp = i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN,
@@ -668,9 +669,6 @@ static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx,
 	struct imx_i2c_dma *dma = i2c_imx->dma;
 	struct device *dev = &i2c_imx->adapter.dev;
 
-	temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
-	temp |= I2CR_DMAEN;
-	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 
 	dma->chan_using = dma->chan_rx;
 	dma->dma_transfer_dir = DMA_DEV_TO_MEM;
@@ -727,7 +725,6 @@ static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx,
 		temp &= ~(I2CR_MSTA | I2CR_MTX);
 		imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 		i2c_imx_bus_busy(i2c_imx, 0);
-		i2c_imx->stopped = 1;
 	} else {
 		/*
 		 * For i2c master receiver repeat restart operation like:
@@ -783,6 +780,7 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, bo
 	int i, result;
 	unsigned int temp;
 	int block_data = msgs->flags & I2C_M_RECV_LEN;
+	int use_dma = i2c_imx->dma && msgs->len >= DMA_THRESHOLD && !block_data;
 
 	dev_dbg(&i2c_imx->adapter.dev,
 		"<%s> write slave address: addr=0x%x\n",
@@ -809,12 +807,14 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, bo
 	 */
 	if ((msgs->len - 1) || block_data)
 		temp &= ~I2CR_TXAK;
+	if (use_dma)
+		temp |= I2CR_DMAEN;
 	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 	imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */
 
 	dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
 
-	if (i2c_imx->dma && msgs->len >= DMA_THRESHOLD && !block_data)
+	if (use_dma)
 		return i2c_imx_dma_read(i2c_imx, msgs, is_lastmsg);
 
 	/* read data */
@@ -850,7 +850,6 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, bo
 				temp &= ~(I2CR_MSTA | I2CR_MTX);
 				imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 				i2c_imx_bus_busy(i2c_imx, 0);
-				i2c_imx->stopped = 1;
 			} else {
 				/*
 				 * For i2c master receiver repeat restart operation like: