From patchwork Sat Jun 19 09:23:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kewei Xu X-Patchwork-Id: 1494613 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=linux-i2c-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4G6Vhc0ffJz9s5R for ; Sat, 19 Jun 2021 19:23:28 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232767AbhFSJZh (ORCPT ); Sat, 19 Jun 2021 05:25:37 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:48564 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S230318AbhFSJZh (ORCPT ); Sat, 19 Jun 2021 05:25:37 -0400 X-UUID: 29926a350148459a98c6dd5a3f9a8a75-20210619 X-UUID: 29926a350148459a98c6dd5a3f9a8a75-20210619 Received: from mtkcas11.mediatek.inc [(172.21.101.40)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1214831891; Sat, 19 Jun 2021 17:23:22 +0800 Received: from MTKCAS06.mediatek.inc (172.21.101.30) by mtkmbs07n1.mediatek.inc (172.21.101.16) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sat, 19 Jun 2021 17:23:20 +0800 Received: from localhost.localdomain (10.17.3.153) by MTKCAS06.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Sat, 19 Jun 2021 17:23:20 +0800 From: To: CC: , , , , , , , , Kewei Xu Subject: [PATCH] i2c: mediatek: Isolate speed setting via dts for special devices Date: Sat, 19 Jun 2021 17:23:17 +0800 Message-ID: <1624094597-23993-1-git-send-email-kewei.xu@mediatek.com> X-Mailer: git-send-email 1.9.1 MIME-Version: 1.0 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org From: Kewei Xu In the commit be5ce0e97cc7 ("i2c: mediatek: Add i2c ac-timing adjust support"), the I2C timing calculation has been revised to support ac-timing, revised to support ac-timing adjustment, however that will break on some I2C components. As a result we want to introduce a new setting "default-adjust-timing" so those components can choose to use the old (default) timing algorithm. Signed-off-by: Kewei Xu --- drivers/i2c/busses/i2c-mt65xx.c | 86 ++++++++++++++++++++++++++++++++++++++--- 1 file changed, 81 insertions(+), 5 deletions(-) diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index ded94f9..486076f 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -41,6 +41,8 @@ #define I2C_HANDSHAKE_RST 0x0020 #define I2C_FIFO_ADDR_CLR 0x0001 #define I2C_DELAY_LEN 0x0002 +#define I2C_ST_START_CON 0x8001 +#define I2C_FS_START_CON 0x1800 #define I2C_TIME_CLR_VALUE 0x0000 #define I2C_TIME_DEFAULT_VALUE 0x0003 #define I2C_WRRD_TRANAC_VALUE 0x0002 @@ -63,6 +65,7 @@ #define I2C_DMA_HARD_RST 0x0002 #define I2C_DMA_HANDSHAKE_RST 0x0004 +#define I2C_DEFAULT_CLK_DIV 5 #define MAX_SAMPLE_CNT_DIV 8 #define MAX_STEP_CNT_DIV 64 #define MAX_CLOCK_DIV 256 @@ -247,6 +250,7 @@ struct mtk_i2c { struct clk *clk_arb; /* Arbitrator clock for i2c */ bool have_pmic; /* can use i2c pins from PMIC */ bool use_push_pull; /* IO config push-pull mode */ + bool default_timing_adjust; /* no timing adjust mode */ u16 irq_stat; /* interrupt status */ unsigned int clk_src_div; @@ -484,6 +488,7 @@ static void mtk_i2c_clock_disable(struct mtk_i2c *i2c) static void mtk_i2c_init_hw(struct mtk_i2c *i2c) { u16 control_reg; + u16 ext_conf_val; if (i2c->dev_comp->apdma_sync) { writel(I2C_DMA_WARM_RST, i2c->pdmabase + OFFSET_RST); @@ -518,8 +523,17 @@ static void mtk_i2c_init_hw(struct mtk_i2c *i2c) if (i2c->dev_comp->ltiming_adjust) mtk_i2c_writew(i2c, i2c->ltiming_reg, OFFSET_LTIMING); - if (i2c->dev_comp->timing_adjust) { - mtk_i2c_writew(i2c, i2c->ac_timing.ext, OFFSET_EXT_CONF); + if (i2c->speed_hz <= I2C_MAX_STANDARD_MODE_FREQ) + ext_conf_val = I2C_ST_START_CON; + else + ext_conf_val = I2C_FS_START_CON; + + if (i2c->default_timing_adjust) { + if (i2c->dev_comp->timing_adjust) + mtk_i2c_writew(i2c, I2C_DEFAULT_CLK_DIV - 1, + OFFSET_CLOCK_DIV); + } else if (i2c->dev_comp->timing_adjust) { + ext_conf_val = i2c->ac_timing.ext; mtk_i2c_writew(i2c, i2c->ac_timing.inter_clk_div, OFFSET_CLOCK_DIV); mtk_i2c_writew(i2c, I2C_SCL_MIS_COMP_VALUE, @@ -544,6 +558,7 @@ static void mtk_i2c_init_hw(struct mtk_i2c *i2c) OFFSET_HS_STA_STO_AC_TIMING); } } + mtk_i2c_writew(i2c, ext_conf_val, OFFSET_EXT_CONF); /* If use i2c pin from PMIC mt6397 side, need set PATH_DIR first */ if (i2c->have_pmic) @@ -600,7 +615,7 @@ static int mtk_i2c_check_ac_timing(struct mtk_i2c *i2c, unsigned int sample_ns = div_u64(1000000000ULL * (sample_cnt + 1), clk_src); - if (!i2c->dev_comp->timing_adjust) + if (i2c->default_timing_adjust || !i2c->dev_comp->timing_adjust) return 0; if (i2c->dev_comp->ltiming_adjust) @@ -760,7 +775,63 @@ static int mtk_i2c_calculate_speed(struct mtk_i2c *i2c, unsigned int clk_src, return 0; } -static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk) +static int mtk_i2c_set_speed_default_timing(struct mtk_i2c *i2c, unsigned int parent_clk) +{ + unsigned int clk_src; + unsigned int step_cnt; + unsigned int sample_cnt; + unsigned int l_step_cnt; + unsigned int l_sample_cnt; + unsigned int target_speed; + int ret; + + if (i2c->dev_comp->timing_adjust) + i2c->clk_src_div *= I2C_DEFAULT_CLK_DIV; + + clk_src = parent_clk / i2c->clk_src_div; + target_speed = i2c->speed_hz; + + if (target_speed > I2C_MAX_FAST_MODE_PLUS_FREQ) { + /* Set master code speed register */ + ret = mtk_i2c_calculate_speed(i2c, clk_src, I2C_MAX_FAST_MODE_FREQ, + &l_step_cnt, &l_sample_cnt); + if (ret < 0) + return ret; + + i2c->timing_reg = (l_sample_cnt << 8) | l_step_cnt; + + /* Set the high speed mode register */ + ret = mtk_i2c_calculate_speed(i2c, clk_src, target_speed, + &step_cnt, &sample_cnt); + if (ret < 0) + return ret; + + i2c->high_speed_reg = I2C_TIME_DEFAULT_VALUE | + (sample_cnt << 12) | (step_cnt << 8); + + if (i2c->dev_comp->ltiming_adjust) + i2c->ltiming_reg = (l_sample_cnt << 6) | l_step_cnt | + (sample_cnt << 12) | (step_cnt << 9); + } else { + ret = mtk_i2c_calculate_speed(i2c, clk_src, target_speed, + &step_cnt, &sample_cnt); + if (ret < 0) + return ret; + + i2c->timing_reg = (sample_cnt << 8) | step_cnt; + + /* Disable the high speed transaction */ + i2c->high_speed_reg = I2C_TIME_CLR_VALUE; + + if (i2c->dev_comp->ltiming_adjust) + i2c->ltiming_reg = (sample_cnt << 6) | step_cnt; + } + + return 0; +} + +static int mtk_i2c_set_speed_adjust_timing(struct mtk_i2c *i2c, + unsigned int parent_clk) { unsigned int clk_src; unsigned int step_cnt; @@ -1284,6 +1355,8 @@ static int mtk_i2c_parse_dt(struct device_node *np, struct mtk_i2c *i2c) i2c->have_pmic = of_property_read_bool(np, "mediatek,have-pmic"); i2c->use_push_pull = of_property_read_bool(np, "mediatek,use-push-pull"); + i2c->default_timing_adjust = + of_property_read_bool(np, "mediatek,default-timing-adjust"); i2c_parse_fw_timings(i2c->dev, &i2c->timing_info, true); @@ -1363,7 +1436,10 @@ static int mtk_i2c_probe(struct platform_device *pdev) strlcpy(i2c->adap.name, I2C_DRV_NAME, sizeof(i2c->adap.name)); - ret = mtk_i2c_set_speed(i2c, clk_get_rate(clk)); + if (i2c->default_timing_adjust) + ret = mtk_i2c_set_speed_default_timing(i2c, clk_get_rate(clk)); + else + ret = mtk_i2c_set_speed_adjust_timing(i2c, clk_get_rate(clk)); if (ret) { dev_err(&pdev->dev, "Failed to set the speed.\n"); return -EINVAL;