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-rw-r--r--drivers/i2c/busses/i2c-img-scb.c30
1 files changed, 17 insertions, 13 deletions
diff --git a/drivers/i2c/busses/i2c-img-scb.c b/drivers/i2c/busses/i2c-img-scb.c
index b4f59e1a5cac..e4daebcdf824 100644
--- a/drivers/i2c/busses/i2c-img-scb.c
+++ b/drivers/i2c/busses/i2c-img-scb.c
@@ -1178,25 +1178,29 @@ static int img_i2c_init(struct img_i2c *i2c)
((bitrate_khz * clk_period) / 2))
int_bitrate++;
- /* Setup TCKH value */
- tckh = DIV_ROUND_UP(timing.tckh, clk_period);
+ /*
+ * Setup clock duty cycle, start with 50% and adjust TCKH and TCKL
+ * values from there if they don't meet minimum timing requirements
+ */
+ tckh = int_bitrate / 2;
+ tckl = int_bitrate - tckh;
- if (tckh > 0)
- data = tckh - 1;
- else
- data = 0;
+ /* Adjust TCKH and TCKL values */
+ data = DIV_ROUND_UP(timing.tckl, clk_period);
- img_i2c_writel(i2c, SCB_TIME_TCKH_REG, data);
+ if (tckl < data) {
+ tckl = data;
+ tckh = int_bitrate - tckl;
+ }
- /* Setup TCKL value */
- tckl = int_bitrate - tckh;
+ if (tckh > 0)
+ --tckh;
if (tckl > 0)
- data = tckl - 1;
- else
- data = 0;
+ --tckl;
- img_i2c_writel(i2c, SCB_TIME_TCKL_REG, data);
+ img_i2c_writel(i2c, SCB_TIME_TCKH_REG, tckh);
+ img_i2c_writel(i2c, SCB_TIME_TCKL_REG, tckl);
/* Setup TSDH value */
tsdh = DIV_ROUND_UP(timing.tsdh, clk_period);