Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a02f3d08 authored by David Wu's avatar David Wu Committed by Wolfram Sang
Browse files

i2c: rk3x: support fast-mode plus for rk3399 



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

Signed-off-by: default avatarDavid Wu <david.wu@rock-chips.com>
Reviewed-by: default avatarDouglas Anderson <dianders@chromium.org>
Tested-by: default avatarCaesar Wang <wxt@rock-chips.com>
Reviewed-by: default avatarHeiko Stuebner <heiko@sntech.de>
Tested-by: default avatarHeiko Stuebner <heiko@sntech.de>
Signed-off-by: default avatarWolfram Sang <wsa@the-dreams.de>
parent 7e086c3f

drivers/i2c/busses/i2c-rk3x.c

+17 −4
Original line number Diff line number Diff line
@@ -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))