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i2c: rk3x: support fast-mode plus for rk3399

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Implement fast mode plus that allows bus speeds of up to 1MHz.

Signed-off-by: David Wu <david.wu@rock-chips.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Caesar Wang <wxt@rock-chips.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
David Wu 2016-05-16 22:06:29 +08:00 committed by Wolfram Sang
parent 7e086c3fc2
commit a02f3d081a
1 changed files with 17 additions and 4 deletions
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21
drivers/i2c/busses/i2c-rk3x.c
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@ -126,6 +126,17 @@ static const struct i2c_spec_values fast_mode_spec = {
.min_hold_buffer_ns = 1300,
};
static const struct i2c_spec_values fast_mode_plus_spec = {
.min_hold_start_ns = 260,
.min_low_ns = 500,
.min_high_ns = 260,
.min_setup_start_ns = 260,
.max_data_hold_ns = 400,
.min_data_setup_ns = 50,
.min_setup_stop_ns = 260,
.min_hold_buffer_ns = 500,
};
/**
* struct rk3x_i2c_calced_timings:
* @div_low: Divider output for low
@ -532,8 +543,10 @@ static const struct i2c_spec_values *rk3x_i2c_get_spec(unsigned int speed)
{
if (speed <= 100000)
return &standard_mode_spec;
else
else if (speed <= 400000)
return &fast_mode_spec;
else
return &fast_mode_plus_spec;
}
/**
@ -744,9 +757,9 @@ static int rk3x_i2c_v1_calc_timings(unsigned long clk_rate,
const struct i2c_spec_values *spec;
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 fast-mode plus */
if (WARN_ON(t->bus_freq_hz > 1000000))
t->bus_freq_hz = 1000000;
/* prevent scl_rate_khz from becoming 0 */
if (WARN_ON(t->bus_freq_hz < 1000))