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-rw-r--r--src/cpu/samsung/exynos5420/i2c.c55
1 files changed, 36 insertions, 19 deletions
diff --git a/src/cpu/samsung/exynos5420/i2c.c b/src/cpu/samsung/exynos5420/i2c.c
index b16d068c5c..acb5bcf7cc 100644
--- a/src/cpu/samsung/exynos5420/i2c.c
+++ b/src/cpu/samsung/exynos5420/i2c.c
@@ -357,23 +357,39 @@ void i2c_init(unsigned bus_num, int speed, int slaveadd)
/*
* Check whether the transfer is complete.
+ * Return values:
+ * 0 - transfer not done
+ * 1 - transfer finished successfully
+ * -1 - transfer failed
*/
static int hsi2c_check_transfer(struct exynos5_hsi2c *i2c)
{
uint32_t status = read32(&i2c->usi_trans_status);
- if (status & HSI2C_TRANS_ABORT)
- printk(BIOS_ERR, "%s: Transaction aborted.\n", __func__);
- if (status & HSI2C_NO_DEV_ACK)
- printk(BIOS_ERR, "%s: No ack from device.\n", __func__);
- if (status & HSI2C_NO_DEV)
- printk(BIOS_ERR, "%s: No response from device.\n", __func__);
- if (status & HSI2C_TIMEOUT_AUTO)
- printk(BIOS_ERR, "%s: Transaction time out.\n", __func__);
- return !!(status & HSI2C_MASTER_BUSY);
+ if (status & (HSI2C_TRANS_ABORT | HSI2C_NO_DEV_ACK |
+ HSI2C_NO_DEV | HSI2C_TIMEOUT_AUTO)) {
+ if (status & HSI2C_TRANS_ABORT)
+ printk(BIOS_ERR,
+ "%s: Transaction aborted.\n", __func__);
+ if (status & HSI2C_NO_DEV_ACK)
+ printk(BIOS_ERR,
+ "%s: No ack from device.\n", __func__);
+ if (status & HSI2C_NO_DEV)
+ printk(BIOS_ERR,
+ "%s: No response from device.\n", __func__);
+ if (status & HSI2C_TIMEOUT_AUTO)
+ printk(BIOS_ERR,
+ "%s: Transaction time out.\n", __func__);
+ return -1;
+ }
+ return !(status & HSI2C_MASTER_BUSY);
}
/*
* Wait for the transfer to finish.
+ * Return values:
+ * 0 - transfer not done
+ * 1 - transfer finished successfully
+ * -1 - transfer failed
*/
static int hsi2c_wait_for_transfer(struct exynos5_hsi2c *i2c)
{
@@ -383,17 +399,18 @@ static int hsi2c_wait_for_transfer(struct exynos5_hsi2c *i2c)
end = current;
mono_time_add_usecs(&end, HSI2C_TIMEOUT * 1000);
while (mono_time_before(&current, &end)) {
- if (!hsi2c_check_transfer(i2c))
- return 0;
+ int ret = hsi2c_check_transfer(i2c);
+ if (ret)
+ return ret;
udelay(5);
timer_monotonic_get(&current);
}
- return 1;
+ return 0;
}
static int hsi2c_senddata(struct exynos5_hsi2c *i2c, uint8_t *data, int len)
{
- while (hsi2c_check_transfer(i2c) && len) {
+ while (!hsi2c_check_transfer(i2c) && len) {
if (!(read32(&i2c->usi_fifo_stat) & HSI2C_TX_FIFO_FULL)) {
write32(*data++, &i2c->usi_txdata);
len--;
@@ -404,7 +421,7 @@ static int hsi2c_senddata(struct exynos5_hsi2c *i2c, uint8_t *data, int len)
static int hsi2c_recvdata(struct exynos5_hsi2c *i2c, uint8_t *data, int len)
{
- while (hsi2c_check_transfer(i2c) && len) {
+ while (!hsi2c_check_transfer(i2c) && len) {
if (!(read32(&i2c->usi_fifo_stat) & HSI2C_RX_FIFO_EMPTY)) {
*data++ = read32(&i2c->usi_rxdata);
len--;
@@ -422,7 +439,7 @@ static int hsi2c_write(struct exynos5_hsi2c *i2c,
{
uint32_t i2c_auto_conf;
- if (hsi2c_wait_for_transfer(i2c))
+ if (hsi2c_wait_for_transfer(i2c) != 1)
return -1;
/* chip address */
@@ -441,7 +458,7 @@ static int hsi2c_write(struct exynos5_hsi2c *i2c,
if (hsi2c_senddata(i2c, addr, alen) ||
hsi2c_senddata(i2c, data, len) ||
- hsi2c_wait_for_transfer(i2c)) {
+ hsi2c_wait_for_transfer(i2c) != 1) {
return -1;
}
@@ -460,7 +477,7 @@ static int hsi2c_read(struct exynos5_hsi2c *i2c,
uint32_t i2c_auto_conf;
/* start read */
- if (hsi2c_wait_for_transfer(i2c))
+ if (hsi2c_wait_for_transfer(i2c) != 1)
return -1;
/* chip address */
@@ -475,7 +492,7 @@ static int hsi2c_read(struct exynos5_hsi2c *i2c,
&i2c->usi_auto_conf);
if (hsi2c_senddata(i2c, addr, alen) ||
- hsi2c_wait_for_transfer(i2c)) {
+ hsi2c_wait_for_transfer(i2c) != 1) {
return -1;
}
@@ -490,7 +507,7 @@ static int hsi2c_read(struct exynos5_hsi2c *i2c,
write32(i2c_auto_conf, &i2c->usi_auto_conf);
if (hsi2c_recvdata(i2c, data, len) ||
- hsi2c_wait_for_transfer(i2c)) {
+ hsi2c_wait_for_transfer(i2c) != 1) {
return -1;
}