Merge branch 'i2c/for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:
 "Features:

   - new drivers: Renesas EMEV2, register based MUX, NXP LPC2xxx
   - core: scans DT and assigns wakeup interrupts.  no driver changes needed.
   - core: some refcouting issues fixed and better API for that
   - core: new helper function for best effort block read emulation
   - slave framework: proper DT bindings and userspace instantiation
   - some bigger work for xiic, pxa, omap drivers

  .. and quite a number of smaller driver fixes, cleanups, improvements"

* 'i2c/for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (65 commits)
  i2c: mux: reg Change ioread endianness for readback
  i2c: mux: reg: fix compilation warnings
  i2c: mux: reg: simplify register size checking
  i2c: muxes: fix leaked i2c adapter device node references
  i2c: allow specifying separate wakeup interrupt in device tree
  of/irq: export of_get_irq_byname()
  i2c: xgene-slimpro: dma_mapping_error() doesn't return an error code
  i2c: Replace I2C_CROS_EC_TUNNEL dependency
  eeprom: at24: use i2c_smbus_read_i2c_block_data_or_emulated
  i2c: core: Add support for best effort block read emulation
  i2c: lpc2k: add driver
  i2c: mux: Add register-based mux i2c-mux-reg
  i2c: dt: describe generic bindings
  i2c: slave: print warning if slave flag not set
  i2c: support 10 bit and slave addresses in sysfs 'new_device'
  i2c: take address space into account when checking for used addresses
  i2c: apply DT flags when probing
  i2c: make address check indpendent from client struct
  i2c: rename address check functions
  i2c: apply address offset for slaves, too
  ...

1 files changed, 17 insertions, 4 deletions

diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index 9920eef74672..c02e6c018c39 100644
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -59,6 +59,7 @@
 #define I2C_DMA_START_EN		0x0001
 #define I2C_DMA_INT_FLAG_NONE		0x0000
 #define I2C_DMA_CLR_FLAG		0x0000
+#define I2C_DMA_HARD_RST		0x0002
 
 #define I2C_DEFAULT_SPEED		100000	/* hz */
 #define MAX_FS_MODE_SPEED		400000
@@ -81,6 +82,7 @@ enum DMA_REGS_OFFSET {
 	OFFSET_INT_FLAG = 0x0,
 	OFFSET_INT_EN = 0x04,
 	OFFSET_EN = 0x08,
+	OFFSET_RST = 0x0c,
 	OFFSET_CON = 0x18,
 	OFFSET_TX_MEM_ADDR = 0x1c,
 	OFFSET_RX_MEM_ADDR = 0x20,
@@ -262,6 +264,10 @@ static void mtk_i2c_init_hw(struct mtk_i2c *i2c)
 		      I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN;
 	writew(control_reg, i2c->base + OFFSET_CONTROL);
 	writew(I2C_DELAY_LEN, i2c->base + OFFSET_DELAY_LEN);
+
+	writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST);
+	udelay(50);
+	writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
 }
 
 /*
@@ -551,15 +557,22 @@ static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id)
 {
 	struct mtk_i2c *i2c = dev_id;
 	u16 restart_flag = 0;
+	u16 intr_stat;
 
 	if (i2c->dev_comp->auto_restart)
 		restart_flag = I2C_RS_TRANSFER;
 
-	i2c->irq_stat = readw(i2c->base + OFFSET_INTR_STAT);
-	writew(restart_flag | I2C_HS_NACKERR | I2C_ACKERR
-		| I2C_TRANSAC_COMP, i2c->base + OFFSET_INTR_STAT);
+	intr_stat = readw(i2c->base + OFFSET_INTR_STAT);
+	writew(intr_stat, i2c->base + OFFSET_INTR_STAT);
 
-	complete(&i2c->msg_complete);
+	/*
+	 * when occurs ack error, i2c controller generate two interrupts
+	 * first is the ack error interrupt, then the complete interrupt
+	 * i2c->irq_stat need keep the two interrupt value.
+	 */
+	i2c->irq_stat |= intr_stat;
+	if (i2c->irq_stat & (I2C_TRANSAC_COMP | restart_flag))
+		complete(&i2c->msg_complete);
 
 	return IRQ_HANDLED;
 }