From: David Wu <david.wu@xxxxxxxxxxxxxx>
The i2c controller of new version1 supports highspeed mode,
1.7M and 3.4M rate. It could be calculated clocks by the rules.
Note: The final divs would be effected a lot by hardware elements like
scl_rise_ns, scl_fall_ns and sda_rise_ns.
Signed-off-by: David Wu <david.wu@xxxxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-rk3x.c | 24 +++++++++++++++++++++---
1 file changed, 21 insertions(+), 3 deletions(-)
diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c
index c82c2f9..f1ea801 100644
--- a/drivers/i2c/busses/i2c-rk3x.c
+++ b/drivers/i2c/busses/i2c-rk3x.c
@@ -704,9 +704,9 @@ static int rk3x_i2c_v1_calc_timings(unsigned long clk_rate,
int ret = 0;
- /* Support standard-mode and fast-mode */
- if (WARN_ON(t->bus_freq_hz > 400000))
- t->bus_freq_hz = 400000;
+ /* Support standard-mode, fast-mode and highspeed-mode */
+ if (WARN_ON(t->bus_freq_hz > 3400000))
+ t->bus_freq_hz = 3400000;
/* prevent scl_rate_khz from becoming 0 */
if (WARN_ON(t->bus_freq_hz < 1000))
@@ -736,6 +736,24 @@ static int rk3x_i2c_v1_calc_timings(unsigned long clk_rate,
spec_min_data_setup_ns = 100;
spec_max_data_hold_ns = 900;
+ } else if (t->bus_freq_hz <= 1700000) {
+ spec_min_low_ns = 320;
+ spec_min_high_ns = 120;
+
+ spec_min_setup_start_ns = 160;
+ spec_min_stop_setup_ns = 160;
+
+ spec_min_data_setup_ns = 10;
+ spec_max_data_hold_ns = 150;
+ } else {
+ spec_min_low_ns = 160;
+ spec_min_high_ns = 60;
+
+ spec_min_setup_start_ns = 160;
+ spec_min_stop_setup_ns = 160;
+
+ spec_min_data_setup_ns = 10;
+ spec_max_data_hold_ns = 70;
}
/* caculate min-divh and min-divl */
--
1.9.1
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