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authorShubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>2020-01-09 17:07:58 +0530
committerWolfram Sang <wsa@the-dreams.de>2020-01-15 21:13:28 +0100
commitb4c119dbc300c7a6ee2da70d5c7ba14747b35142 (patch)
treed5f596270a709549b52c50814a080ff8e1558b17 /drivers/i2c
parent40b2ec1251c370bc5557568e259d4058c651d405 (diff)
downloadlinux-b4c119dbc300c7a6ee2da70d5c7ba14747b35142.tar.bz2
i2c: xiic: Add timeout to the rx fifo wait loop
Add timeout to the rx fifo empty wait loop. Also check for the return value for xiic_reinit and pass it to xiic_start_xfer. Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com> Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-xiic.c52
1 files changed, 42 insertions, 10 deletions
diff --git a/drivers/i2c/busses/i2c-xiic.c b/drivers/i2c/busses/i2c-xiic.c
index 61e081b186cc..3a403202bd28 100644
--- a/drivers/i2c/busses/i2c-xiic.c
+++ b/drivers/i2c/busses/i2c-xiic.c
@@ -156,6 +156,8 @@ struct xiic_i2c {
#define XIIC_RESET_MASK 0xAUL
#define XIIC_PM_TIMEOUT 1000 /* ms */
+/* timeout waiting for the controller to respond */
+#define XIIC_I2C_TIMEOUT (msecs_to_jiffies(1000))
/*
* The following constant is used for the device global interrupt enable
* register, to enable all interrupts for the device, this is the only bit
@@ -166,7 +168,7 @@ struct xiic_i2c {
#define xiic_tx_space(i2c) ((i2c)->tx_msg->len - (i2c)->tx_pos)
#define xiic_rx_space(i2c) ((i2c)->rx_msg->len - (i2c)->rx_pos)
-static void xiic_start_xfer(struct xiic_i2c *i2c);
+static int xiic_start_xfer(struct xiic_i2c *i2c);
static void __xiic_start_xfer(struct xiic_i2c *i2c);
/*
@@ -247,17 +249,29 @@ static inline void xiic_irq_clr_en(struct xiic_i2c *i2c, u32 mask)
xiic_irq_en(i2c, mask);
}
-static void xiic_clear_rx_fifo(struct xiic_i2c *i2c)
+static int xiic_clear_rx_fifo(struct xiic_i2c *i2c)
{
u8 sr;
+ unsigned long timeout;
+
+ timeout = jiffies + XIIC_I2C_TIMEOUT;
for (sr = xiic_getreg8(i2c, XIIC_SR_REG_OFFSET);
!(sr & XIIC_SR_RX_FIFO_EMPTY_MASK);
- sr = xiic_getreg8(i2c, XIIC_SR_REG_OFFSET))
+ sr = xiic_getreg8(i2c, XIIC_SR_REG_OFFSET)) {
xiic_getreg8(i2c, XIIC_DRR_REG_OFFSET);
+ if (time_after(jiffies, timeout)) {
+ dev_err(i2c->dev, "Failed to clear rx fifo\n");
+ return -ETIMEDOUT;
+ }
+ }
+
+ return 0;
}
-static void xiic_reinit(struct xiic_i2c *i2c)
+static int xiic_reinit(struct xiic_i2c *i2c)
{
+ int ret;
+
xiic_setreg32(i2c, XIIC_RESETR_OFFSET, XIIC_RESET_MASK);
/* Set receive Fifo depth to maximum (zero based). */
@@ -270,12 +284,16 @@ static void xiic_reinit(struct xiic_i2c *i2c)
xiic_setreg8(i2c, XIIC_CR_REG_OFFSET, XIIC_CR_ENABLE_DEVICE_MASK);
/* make sure RX fifo is empty */
- xiic_clear_rx_fifo(i2c);
+ ret = xiic_clear_rx_fifo(i2c);
+ if (ret)
+ return ret;
/* Enable interrupts */
xiic_setreg32(i2c, XIIC_DGIER_OFFSET, XIIC_GINTR_ENABLE_MASK);
xiic_irq_clr_en(i2c, XIIC_INTR_ARB_LOST_MASK);
+
+ return 0;
}
static void xiic_deinit(struct xiic_i2c *i2c)
@@ -655,12 +673,18 @@ static void __xiic_start_xfer(struct xiic_i2c *i2c)
}
-static void xiic_start_xfer(struct xiic_i2c *i2c)
+static int xiic_start_xfer(struct xiic_i2c *i2c)
{
+ int ret;
mutex_lock(&i2c->lock);
- xiic_reinit(i2c);
- __xiic_start_xfer(i2c);
+
+ ret = xiic_reinit(i2c);
+ if (!ret)
+ __xiic_start_xfer(i2c);
+
mutex_unlock(&i2c->lock);
+
+ return ret;
}
static int xiic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
@@ -682,7 +706,11 @@ static int xiic_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
i2c->tx_msg = msgs;
i2c->nmsgs = num;
- xiic_start_xfer(i2c);
+ err = xiic_start_xfer(i2c);
+ if (err < 0) {
+ dev_err(adap->dev.parent, "Error xiic_start_xfer\n");
+ goto out;
+ }
if (wait_event_timeout(i2c->wait, (i2c->state == STATE_ERROR) ||
(i2c->state == STATE_DONE), HZ)) {
@@ -794,7 +822,11 @@ static int xiic_i2c_probe(struct platform_device *pdev)
if (!(sr & XIIC_SR_TX_FIFO_EMPTY_MASK))
i2c->endianness = BIG;
- xiic_reinit(i2c);
+ ret = xiic_reinit(i2c);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Cannot xiic_reinit\n");
+ goto err_clk_dis;
+ }
/* add i2c adapter to i2c tree */
ret = i2c_add_adapter(&i2c->adap);