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

Pull i2c fixes from Wolfram Sang:

 - two driver fixes

 - better parameter check for the core

 - Documentation updates

 - part of a tree-wide HAS_DMA cleanup

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: sprd: Fix the i2c count issue
  i2c: sprd: Prevent i2c accesses after suspend is called
  i2c: dev: prevent ZERO_SIZE_PTR deref in i2cdev_ioctl_rdwr()
  Documentation/i2c: adopt kernel commenting style in examples
  Documentation/i2c: sync docs with current state of i2c-tools
  Documentation/i2c: whitespace cleanup
  i2c: Remove depends on HAS_DMA in case of platform dependency

3 files changed, 19 insertions, 8 deletions

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index c4865b08d7fb..8d21b9825d71 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -707,7 +707,6 @@ config I2C_MPC
 config I2C_MT65XX
 	tristate "MediaTek I2C adapter"
 	depends on ARCH_MEDIATEK || COMPILE_TEST
-	depends on HAS_DMA
 	help
 	  This selects the MediaTek(R) Integrated Inter Circuit bus driver
 	  for MT65xx and MT81xx.
@@ -885,7 +884,6 @@ config I2C_SH7760
 
 config I2C_SH_MOBILE
 	tristate "SuperH Mobile I2C Controller"
-	depends on HAS_DMA
 	depends on ARCH_SHMOBILE || ARCH_RENESAS || COMPILE_TEST
 	help
 	  If you say yes to this option, support will be included for the
@@ -1098,7 +1096,6 @@ config I2C_XLP9XX
 
 config I2C_RCAR
 	tristate "Renesas R-Car I2C Controller"
-	depends on HAS_DMA
 	depends on ARCH_RENESAS || COMPILE_TEST
 	select I2C_SLAVE
 	help
diff --git a/drivers/i2c/busses/i2c-sprd.c b/drivers/i2c/busses/i2c-sprd.c
index 25fcc3c1e32b..4053259bccb8 100644
--- a/drivers/i2c/busses/i2c-sprd.c
+++ b/drivers/i2c/busses/i2c-sprd.c
@@ -86,6 +86,7 @@ struct sprd_i2c {
 	u32 count;
 	int irq;
 	int err;
+	bool is_suspended;
 };
 
 static void sprd_i2c_set_count(struct sprd_i2c *i2c_dev, u32 count)
@@ -283,6 +284,9 @@ static int sprd_i2c_master_xfer(struct i2c_adapter *i2c_adap,
 	struct sprd_i2c *i2c_dev = i2c_adap->algo_data;
 	int im, ret;
 
+	if (i2c_dev->is_suspended)
+		return -EBUSY;
+
 	ret = pm_runtime_get_sync(i2c_dev->dev);
 	if (ret < 0)
 		return ret;
@@ -364,13 +368,12 @@ static irqreturn_t sprd_i2c_isr_thread(int irq, void *dev_id)
 	struct sprd_i2c *i2c_dev = dev_id;
 	struct i2c_msg *msg = i2c_dev->msg;
 	bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK);
-	u32 i2c_count = readl(i2c_dev->base + I2C_COUNT);
 	u32 i2c_tran;
 
 	if (msg->flags & I2C_M_RD)
 		i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD;
 	else
-		i2c_tran = i2c_count;
+		i2c_tran = i2c_dev->count;
 
 	/*
 	 * If we got one ACK from slave when writing data, and we did not
@@ -408,14 +411,13 @@ static irqreturn_t sprd_i2c_isr(int irq, void *dev_id)
 {
 	struct sprd_i2c *i2c_dev = dev_id;
 	struct i2c_msg *msg = i2c_dev->msg;
-	u32 i2c_count = readl(i2c_dev->base + I2C_COUNT);
 	bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK);
 	u32 i2c_tran;
 
 	if (msg->flags & I2C_M_RD)
 		i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD;
 	else
-		i2c_tran = i2c_count;
+		i2c_tran = i2c_dev->count;
 
 	/*
 	 * If we did not get one ACK from slave when writing data, then we
@@ -586,11 +588,23 @@ static int sprd_i2c_remove(struct platform_device *pdev)
 
 static int __maybe_unused sprd_i2c_suspend_noirq(struct device *pdev)
 {
+	struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev);
+
+	i2c_lock_adapter(&i2c_dev->adap);
+	i2c_dev->is_suspended = true;
+	i2c_unlock_adapter(&i2c_dev->adap);
+
 	return pm_runtime_force_suspend(pdev);
 }
 
 static int __maybe_unused sprd_i2c_resume_noirq(struct device *pdev)
 {
+	struct sprd_i2c *i2c_dev = dev_get_drvdata(pdev);
+
+	i2c_lock_adapter(&i2c_dev->adap);
+	i2c_dev->is_suspended = false;
+	i2c_unlock_adapter(&i2c_dev->adap);
+
 	return pm_runtime_force_resume(pdev);
 }
 
diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index 036a03f0d0a6..1667b6e7674f 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -280,7 +280,7 @@ static noinline int i2cdev_ioctl_rdwr(struct i2c_client *client,
 		 */
 		if (msgs[i].flags & I2C_M_RECV_LEN) {
 			if (!(msgs[i].flags & I2C_M_RD) ||
-			    msgs[i].buf[0] < 1 ||
+			    msgs[i].len < 1 || msgs[i].buf[0] < 1 ||
 			    msgs[i].len < msgs[i].buf[0] +
 					     I2C_SMBUS_BLOCK_MAX) {
 				res = -EINVAL;