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-rw-r--r--drivers/i2c/mxs_i2c.c39
1 files changed, 32 insertions, 7 deletions
diff --git a/drivers/i2c/mxs_i2c.c b/drivers/i2c/mxs_i2c.c
index a298c95..de3b194 100644
--- a/drivers/i2c/mxs_i2c.c
+++ b/drivers/i2c/mxs_i2c.c
@@ -64,16 +64,17 @@ static void mxs_i2c_setup_read(uint8_t chip, int len)
writel(I2C_QUEUECTRL_QUEUE_RUN, &i2c_regs->hw_i2c_queuectrl_set);
}
-static void mxs_i2c_write(uchar chip, uint addr, int alen,
+static int mxs_i2c_write(uchar chip, uint addr, int alen,
uchar *buf, int blen, int stop)
{
struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
- uint32_t data;
+ uint32_t data, tmp;
int i, remain, off;
+ int timeout = MXS_I2C_MAX_TIMEOUT;
if ((alen > 4) || (alen == 0)) {
debug("MXS I2C: Invalid address length\n");
- return;
+ return -EINVAL;
}
if (stop)
@@ -106,6 +107,19 @@ static void mxs_i2c_write(uchar chip, uint addr, int alen,
writel(data >> remain, &i2c_regs->hw_i2c_data);
writel(I2C_QUEUECTRL_QUEUE_RUN, &i2c_regs->hw_i2c_queuectrl_set);
+
+ while (--timeout) {
+ tmp = readl(&i2c_regs->hw_i2c_queuestat);
+ if (tmp & I2C_QUEUESTAT_WR_QUEUE_EMPTY)
+ break;
+ }
+
+ if (!timeout) {
+ debug("MXS I2C: Failed transmitting data!\n");
+ return -EINVAL;
+ }
+
+ return 0;
}
static int mxs_i2c_wait_for_ack(void)
@@ -154,7 +168,12 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
int ret;
int i;
- mxs_i2c_write(chip, addr, alen, NULL, 0, 0);
+ ret = mxs_i2c_write(chip, addr, alen, NULL, 0, 0);
+ if (ret) {
+ debug("MXS I2C: Failed writing address\n");
+ return ret;
+ }
+
ret = mxs_i2c_wait_for_ack();
if (ret) {
debug("MXS I2C: Failed writing address\n");
@@ -193,7 +212,12 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
{
int ret;
- mxs_i2c_write(chip, addr, alen, buffer, len, 1);
+ ret = mxs_i2c_write(chip, addr, alen, buffer, len, 1);
+ if (ret) {
+ debug("MXS I2C: Failed writing address\n");
+ return ret;
+ }
+
ret = mxs_i2c_wait_for_ack();
if (ret)
debug("MXS I2C: Failed writing address\n");
@@ -204,8 +228,9 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len)
int i2c_probe(uchar chip)
{
int ret;
- mxs_i2c_write(chip, 0, 1, NULL, 0, 1);
- ret = mxs_i2c_wait_for_ack();
+ ret = mxs_i2c_write(chip, 0, 1, NULL, 0, 1);
+ if (!ret)
+ ret = mxs_i2c_wait_for_ack();
mxs_i2c_reset();
return ret;
}