From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934571AbcCOOrF (ORCPT ); Tue, 15 Mar 2016 10:47:05 -0400 Received: from lucky1.263xmail.com ([211.157.147.133]:53296 "EHLO lucky1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933299AbcCOOrB (ORCPT ); Tue, 15 Mar 2016 10:47:01 -0400 X-263anti-spam: KSV:0; X-MAIL-GRAY: 1 X-MAIL-DELIVERY: 0 X-KSVirus-check: 0 X-ABS-CHECKED: 4 X-ADDR-CHECKED: 0 X-RL-SENDER: david.wu@rock-chips.com X-SENDER-IP: 58.22.7.114 X-LOGIN-NAME: david.wu@rock-chips.com X-UNIQUE-TAG: <9ffc011b79b405d8f4b152dd21a9470f> X-ATTACHMENT-NUM: 0 X-DNS-TYPE: 0 From: David Wu To: heiko@sntech.de, wsa@the-dreams.de Cc: dianders@chromium.org, andy.shevchenko@gmail.com, huangtao@rock-chips.com, hl@rock-chips.com, xjq@rock-chips.com, zyw@rock-chips.com, cf@rock-chips.com, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, david.wu@rock-chips.com Subject: [PATCH v4 3/3] i2c: rk3x: support I2C Highspeed Mode for rk3399 Date: Tue, 15 Mar 2016 06:52:30 +0800 Message-Id: <1457995950-46710-4-git-send-email-wdc@rock-chips.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1457995950-46710-1-git-send-email-wdc@rock-chips.com> References: <1457995950-46710-1-git-send-email-wdc@rock-chips.com> Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: David Wu 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 --- 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