From patchwork Fri Jan 16 10:33:38 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?b?RWRkaWUgSHVhbmcgKOm7g+aZuuWCkSk=?= X-Patchwork-Id: 5646961 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id E2F2CC058D for ; Fri, 16 Jan 2015 10:38:00 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 22E2920172 for ; Fri, 16 Jan 2015 10:37:59 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 454CB201EC for ; Fri, 16 Jan 2015 10:37:57 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YC4Fk-0003AE-U3; Fri, 16 Jan 2015 10:35:44 +0000 Received: from [210.61.82.183] (helo=mailgw01.mediatek.com) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1YC4FF-0001mg-Qz for linux-arm-kernel@lists.infradead.org; Fri, 16 Jan 2015 10:35:17 +0000 X-Listener-Flag: 11101 Received: from mtkhts07.mediatek.inc [(172.21.101.69)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 582788605; Fri, 16 Jan 2015 18:34:44 +0800 Received: from mtkslt208.mediatek.inc (10.21.15.95) by mtkhts07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 14.3.181.6; Fri, 16 Jan 2015 18:34:43 +0800 From: Eddie Huang To: Wolfram Sang , Matthias Brugger Subject: [PATCH v4 2/2] I2C: mediatek: Add driver for MediaTek I2C controller Date: Fri, 16 Jan 2015 18:33:38 +0800 Message-ID: <1421404418-50718-3-git-send-email-eddie.huang@mediatek.com> X-Mailer: git-send-email 1.8.1.1.dirty In-Reply-To: <1421404418-50718-1-git-send-email-eddie.huang@mediatek.com> References: <1421404418-50718-1-git-send-email-eddie.huang@mediatek.com> MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150116_023514_609266_22E09FA7 X-CRM114-Status: GOOD ( 19.28 ) X-Spam-Score: 1.3 (+) Cc: Mark Rutland , Andrew Bresticker , linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, Lee Jones , Jean Delvare , Xudong Chen , Boris BREZILLON , Arnd Bergmann , yh.chen@mediatek.com, Wei Yan , Bjorn Andersson , Uwe Kleine-Konig , Neelesh Gupta , yingjoe.chen@mediatek.com, devicetree@vger.kernel.org, Pawel Moll , Ian Campbell , Beniamino Galvani , Grant Likely , Rob Herring , Eddie Huang , linux-arm-kernel@lists.infradead.org, srv_heupstream@mediatek.com, Anders Berg , Jim Cromie , Simon Glass , Max Schwarz , Doug Anderson , Sascha Hauer , Kumar Gala X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Xudong Chen The mediatek SoCs have I2C controller that handle I2C transfer. This patch include common I2C bus driver. This driver is compatible with I2C controller on mt65xx/mt81xx. Signed-off-by: Xudong Chen Signed-off-by: Eddie Huang --- drivers/i2c/busses/Kconfig | 9 + drivers/i2c/busses/Makefile | 1 + drivers/i2c/busses/i2c-mt65xx.c | 710 ++++++++++++++++++++++++++++++++++++++++ 3 files changed, 720 insertions(+) create mode 100644 drivers/i2c/busses/i2c-mt65xx.c diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index 31e8308..7c76693 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -582,6 +582,15 @@ config I2C_MPC This driver can also be built as a module. If so, the module will be called i2c-mpc. +config I2C_MT65XX + tristate "MediaTek I2C adapter" + depends on ARCH_MEDIATEK + help + This selects the MediaTek(R) Integrated Inter Circuit bus driver + for MT65xx and MT81xx. + If you want to use MediaTek(R) I2C interface, say Y or M here. + If unsure, say N. + config I2C_MV64XXX tristate "Marvell mv64xxx I2C Controller" depends on MV64X60 || PLAT_ORION || ARCH_SUNXI diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 56388f6..59cbb4b 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -56,6 +56,7 @@ obj-$(CONFIG_I2C_IOP3XX) += i2c-iop3xx.o obj-$(CONFIG_I2C_KEMPLD) += i2c-kempld.o obj-$(CONFIG_I2C_MESON) += i2c-meson.o obj-$(CONFIG_I2C_MPC) += i2c-mpc.o +obj-$(CONFIG_I2C_MT65XX) += i2c-mt65xx.o obj-$(CONFIG_I2C_MV64XXX) += i2c-mv64xxx.o obj-$(CONFIG_I2C_MXS) += i2c-mxs.o obj-$(CONFIG_I2C_NOMADIK) += i2c-nomadik.o diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c new file mode 100644 index 0000000..21bbe3b --- /dev/null +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -0,0 +1,710 @@ +/* + * Copyright (c) 2014 MediaTek Inc. + * Author: Xudong.chen + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define I2C_HS_NACKERR (1 << 2) +#define I2C_ACKERR (1 << 1) +#define I2C_TRANSAC_COMP (1 << 0) +#define I2C_TRANSAC_START (1 << 0) +#define I2C_TIMING_STEP_DIV_MASK (0x3f << 0) +#define I2C_TIMING_SAMPLE_COUNT_MASK (0x7 << 0) +#define I2C_TIMING_SAMPLE_DIV_MASK (0x7 << 8) +#define I2C_TIMING_DATA_READ_MASK (0x7 << 12) +#define I2C_DCM_DISABLE 0x0000 +#define I2C_IO_CONFIG_OPEN_DRAIN 0x0003 +#define I2C_IO_CONFIG_PUSH_PULL 0x0000 +#define I2C_SOFT_RST 0x0001 +#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_FS_TIME_INIT_VALUE 0x1303 +#define I2C_WRRD_TRANAC_VALUE 0x0002 +#define I2C_RD_TRANAC_VALUE 0x0001 + +#define I2C_DMA_CON_TX 0x0000 +#define I2C_DMA_CON_RX 0x0001 +#define I2C_DMA_START_EN 0x0001 +#define I2C_DMA_INT_FLAG_NONE 0x0000 +#define I2C_DMA_CLR_FLAG 0x0000 + +#define I2C_DEFAUT_SPEED 100000 /* hz */ +#define MAX_FS_MODE_SPEED 400000 +#define MAX_HS_MODE_SPEED 3400000 +#define MAX_DMA_TRANS_SIZE 255 +#define MAX_WRRD_TRANS_SIZE 31 +#define MAX_SAMPLE_CNT_DIV 8 +#define MAX_STEP_CNT_DIV 64 +#define MAX_HS_STEP_CNT_DIV 8 + +#define I2C_CONTROL_RS (0x1 << 1) +#define I2C_CONTROL_DMA_EN (0x1 << 2) +#define I2C_CONTROL_CLK_EXT_EN (0x1 << 3) +#define I2C_CONTROL_DIR_CHANGE (0x1 << 4) +#define I2C_CONTROL_ACKERR_DET_EN (0x1 << 5) +#define I2C_CONTROL_TRANSFER_LEN_CHANGE (0x1 << 6) +#define I2C_CONTROL_WRAPPER (0x1 << 0) + +#define COMPAT_MT6577 (0x1 << 0) +#define COMPAT_MT6589 (0x1 << 1) + +#define I2C_DRV_NAME "mt-i2c" + +enum DMA_REGS_OFFSET { + OFFSET_INT_FLAG = 0x0, + OFFSET_INT_EN = 0x04, + OFFSET_EN = 0x08, + OFFSET_CON = 0x18, + OFFSET_TX_MEM_ADDR = 0x1c, + OFFSET_RX_MEM_ADDR = 0x20, + OFFSET_TX_LEN = 0x24, + OFFSET_RX_LEN = 0x28, +}; + +enum i2c_trans_st_rs { + I2C_TRANS_STOP = 0, + I2C_TRANS_REPEATED_START, +}; + +enum { + FS_MODE, + HS_MODE, +}; + +enum mtk_trans_op { + I2C_MASTER_WR = 1, + I2C_MASTER_RD, + I2C_MASTER_WRRD, +}; + +enum I2C_REGS_OFFSET { + OFFSET_DATA_PORT = 0x0, + OFFSET_SLAVE_ADDR = 0x04, + OFFSET_INTR_MASK = 0x08, + OFFSET_INTR_STAT = 0x0c, + OFFSET_CONTROL = 0x10, + OFFSET_TRANSFER_LEN = 0x14, + OFFSET_TRANSAC_LEN = 0x18, + OFFSET_DELAY_LEN = 0x1c, + OFFSET_TIMING = 0x20, + OFFSET_START = 0x24, + OFFSET_EXT_CONF = 0x28, + OFFSET_FIFO_STAT = 0x30, + OFFSET_FIFO_THRESH = 0x34, + OFFSET_FIFO_ADDR_CLR = 0x38, + OFFSET_IO_CONFIG = 0x40, + OFFSET_RSV_DEBUG = 0x44, + OFFSET_HS = 0x48, + OFFSET_SOFTRESET = 0x50, + OFFSET_DCM_EN = 0x54, + OFFSET_PATH_DIR = 0x60, + OFFSET_DEBUGSTAT = 0x64, + OFFSET_DEBUGCTRL = 0x68, + OFFSET_TRANSFER_LEN_AUX = 0x6c, +}; + +struct mtk_i2c_data { + unsigned int clk_frequency; /* bus speed in Hz */ + unsigned int flags; + unsigned int clk_src_div; +}; + +struct i2c_dma_buf { + u8 *vaddr; + dma_addr_t paddr; +}; + +struct mtk_i2c { + struct i2c_adapter adap; /* i2c host adapter */ + struct device *dev; + wait_queue_head_t wait; /* i2c transfer wait queue */ + /* set in i2c probe */ + void __iomem *base; /* i2c base addr */ + void __iomem *pdmabase; /* dma base address*/ + int irqnr; /* i2c interrupt number */ + struct i2c_dma_buf dma_buf; /* memory alloc for DMA mode */ + struct clk *clk_main; /* main clock for i2c bus */ + struct clk *clk_dma; /* DMA clock for i2c via DMA */ + struct clk *clk_pmic; /* PMIC clock for i2c from PMIC */ + bool have_pmic; /* can use i2c pins from PMIC */ + bool use_push_pull; /* IO config push-pull mode */ + u32 platform_compat; /* platform compatible data */ + /* set when doing the transfer */ + u16 irq_stat; /* interrupt status */ + unsigned int speed_hz; /* The speed in transfer */ + bool trans_stop; /* i2c transfer stop */ + enum mtk_trans_op op; + u16 msg_len; + u8 *msg_buf; /* pointer to msg data */ + u16 msg_aux_len; /* WRRD mode to set AUX_LEN register*/ + u16 addr; /* 7bit slave address, without read/write bit */ + u16 timing_reg; + u16 high_speed_reg; +}; + +static const struct of_device_id mtk_i2c_of_match[] = { + { .compatible = "mediatek,mt6577-i2c", .data = (void *)COMPAT_MT6577 }, + { .compatible = "mediatek,mt6589-i2c", .data = (void *)COMPAT_MT6589 }, + {}, +}; +MODULE_DEVICE_TABLE(of, mtk_i2c_match); + +static inline void i2c_writew(u16 value, struct mtk_i2c *i2c, u8 offset) +{ + writew(value, i2c->base + offset); +} + +static inline u16 i2c_readw(struct mtk_i2c *i2c, u8 offset) +{ + return readw(i2c->base + offset); +} + +static inline void i2c_writel_dma(u32 value, struct mtk_i2c *i2c, u8 offset) +{ + writel(value, i2c->pdmabase + offset); +} + +static int mtk_i2c_clock_enable(struct mtk_i2c *i2c) +{ + int ret; + + ret = clk_prepare_enable(i2c->clk_dma); + if (ret) + return ret; + + ret = clk_prepare_enable(i2c->clk_main); + if (ret) + goto err_main; + + if (i2c->have_pmic) { + ret = clk_prepare_enable(i2c->clk_pmic); + if (ret) + goto err_pmic; + } + return 0; + +err_pmic: + clk_disable_unprepare(i2c->clk_main); +err_main: + clk_disable_unprepare(i2c->clk_dma); + + return ret; +} + +static void mtk_i2c_clock_disable(struct mtk_i2c *i2c) +{ + if (i2c->have_pmic) + clk_disable_unprepare(i2c->clk_pmic); + + clk_disable_unprepare(i2c->clk_main); + clk_disable_unprepare(i2c->clk_dma); +} + +static void free_i2c_dma_bufs(struct mtk_i2c *i2c) +{ + dma_free_coherent(i2c->adap.dev.parent, PAGE_SIZE, + i2c->dma_buf.vaddr, i2c->dma_buf.paddr); +} + +static inline void mtk_i2c_init_hw(struct mtk_i2c *i2c) +{ + i2c_writew(I2C_SOFT_RST, i2c, OFFSET_SOFTRESET); + /* Set ioconfig */ + if (i2c->use_push_pull) + i2c_writew(I2C_IO_CONFIG_PUSH_PULL, i2c, OFFSET_IO_CONFIG); + else + i2c_writew(I2C_IO_CONFIG_OPEN_DRAIN, i2c, OFFSET_IO_CONFIG); + + if (i2c->platform_compat & COMPAT_MT6577) + i2c_writew(I2C_DCM_DISABLE, i2c, OFFSET_DCM_EN); + + i2c_writew(i2c->timing_reg, i2c, OFFSET_TIMING); + i2c_writew(i2c->high_speed_reg, i2c, OFFSET_HS); +} + +/* calculate i2c port speed */ +static int i2c_set_speed(struct mtk_i2c *i2c, unsigned int clk_src_in_hz) +{ + int mode; + unsigned int khz; + unsigned int step_cnt; + unsigned int sample_cnt; + unsigned int sclk; + unsigned int hclk; + unsigned int max_step_cnt; + unsigned int sample_div = MAX_SAMPLE_CNT_DIV; + unsigned int step_div; + unsigned int min_div; + unsigned int best_mul; + unsigned int cnt_mul; + + if (i2c->speed_hz > MAX_HS_MODE_SPEED) { + return -EINVAL; + } else if (i2c->speed_hz > MAX_FS_MODE_SPEED) { + mode = HS_MODE; + max_step_cnt = MAX_HS_STEP_CNT_DIV; + } else { + mode = FS_MODE; + max_step_cnt = MAX_STEP_CNT_DIV; + } + + step_div = max_step_cnt; + /* Find the best combination */ + khz = i2c->speed_hz / 1000; + hclk = clk_src_in_hz / 1000; + min_div = ((hclk >> 1) + khz - 1) / khz; + best_mul = MAX_SAMPLE_CNT_DIV * max_step_cnt; + + for (sample_cnt = 1; sample_cnt <= MAX_SAMPLE_CNT_DIV; sample_cnt++) { + step_cnt = (min_div + sample_cnt - 1) / sample_cnt; + cnt_mul = step_cnt * sample_cnt; + if (step_cnt > max_step_cnt) + continue; + + if (cnt_mul < best_mul) { + best_mul = cnt_mul; + sample_div = sample_cnt; + step_div = step_cnt; + if (best_mul == min_div) + break; + } + } + + sample_cnt = sample_div; + step_cnt = step_div; + sclk = hclk / (2 * sample_cnt * step_cnt); + if (sclk > khz) { + dev_dbg(i2c->dev, "%s mode: unsupported speed (%ldkhz)\n", + (mode == HS_MODE) ? "HS" : "ST/FT", (long int)khz); + return -ENOTSUPP; + } + + step_cnt--; + sample_cnt--; + + if (mode == HS_MODE) { + /* Set the hign speed mode register */ + i2c->timing_reg = I2C_FS_TIME_INIT_VALUE; + i2c->high_speed_reg = I2C_TIME_DEFAULT_VALUE | + (sample_cnt & I2C_TIMING_SAMPLE_COUNT_MASK) << 12 | + (step_cnt & I2C_TIMING_SAMPLE_COUNT_MASK) << 8; + } else { + i2c->timing_reg = + (sample_cnt & I2C_TIMING_SAMPLE_COUNT_MASK) << 8 | + (step_cnt & I2C_TIMING_STEP_DIV_MASK) << 0; + /* Disable the high speed transaction */ + i2c->high_speed_reg = I2C_TIME_CLR_VALUE; + } + + return 0; +} + +static int mtk_i2c_do_transfer(struct mtk_i2c *i2c) +{ + u16 addr_reg; + u16 control_reg; + int tmo = i2c->adap.timeout; + + i2c->trans_stop = false; + i2c->irq_stat = 0; + + /* If use i2c pin from PMIC mt6397 side, need set PATH_DIR first */ + if (i2c->have_pmic) + i2c_writew(I2C_CONTROL_WRAPPER, i2c, OFFSET_PATH_DIR); + + control_reg = I2C_CONTROL_ACKERR_DET_EN | + I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN; + if (i2c->speed_hz > 400000) + control_reg |= I2C_CONTROL_RS; + if (i2c->op == I2C_MASTER_WRRD) + control_reg |= I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS; + i2c_writew(control_reg, i2c, OFFSET_CONTROL); + + /* set start condition */ + if (i2c->speed_hz <= 100000) + i2c_writew(I2C_ST_START_CON, i2c, OFFSET_EXT_CONF); + else + i2c_writew(I2C_FS_START_CON, i2c, OFFSET_EXT_CONF); + + if (~control_reg & I2C_CONTROL_RS) + i2c_writew(I2C_DELAY_LEN, i2c, OFFSET_DELAY_LEN); + + addr_reg = i2c->addr << 1; + if (i2c->op == I2C_MASTER_RD) + addr_reg |= 0x1; + i2c_writew(addr_reg, i2c, OFFSET_SLAVE_ADDR); + + /* Clear interrupt status */ + i2c_writew(I2C_HS_NACKERR | I2C_ACKERR | I2C_TRANSAC_COMP, + i2c, OFFSET_INTR_STAT); + i2c_writew(I2C_FIFO_ADDR_CLR, i2c, OFFSET_FIFO_ADDR_CLR); + + /* Enable interrupt */ + i2c_writew(I2C_HS_NACKERR | I2C_ACKERR | I2C_TRANSAC_COMP, + i2c, OFFSET_INTR_MASK); + + /* Set transfer and transaction len */ + if (i2c->op == I2C_MASTER_WRRD) { + i2c_writew(i2c->msg_len | (i2c->msg_aux_len) << 8, + i2c, OFFSET_TRANSFER_LEN); + i2c_writew(I2C_WRRD_TRANAC_VALUE, i2c, OFFSET_TRANSAC_LEN); + } else { + i2c_writew(i2c->msg_len, i2c, OFFSET_TRANSFER_LEN); + i2c_writew(I2C_RD_TRANAC_VALUE, i2c, OFFSET_TRANSAC_LEN); + } + + /* Prepare buffer data to start transfer */ + if (i2c->op == I2C_MASTER_RD) { + i2c_writel_dma(I2C_DMA_INT_FLAG_NONE, i2c, OFFSET_INT_FLAG); + i2c_writel_dma(I2C_DMA_CON_RX, i2c, OFFSET_CON); + i2c_writel_dma((u32)i2c->msg_buf, i2c, OFFSET_RX_MEM_ADDR); + i2c_writel_dma(i2c->msg_len, i2c, OFFSET_RX_LEN); + } else if (i2c->op == I2C_MASTER_WR) { + i2c_writel_dma(I2C_DMA_INT_FLAG_NONE, i2c, OFFSET_INT_FLAG); + i2c_writel_dma(I2C_DMA_CON_TX, i2c, OFFSET_CON); + i2c_writel_dma((u32)i2c->msg_buf, i2c, OFFSET_TX_MEM_ADDR); + i2c_writel_dma(i2c->msg_len, i2c, OFFSET_TX_LEN); + } else { + i2c_writel_dma(I2C_DMA_CLR_FLAG, i2c, OFFSET_INT_FLAG); + i2c_writel_dma(I2C_DMA_CLR_FLAG, i2c, OFFSET_CON); + i2c_writel_dma((u32)i2c->msg_buf, i2c, OFFSET_TX_MEM_ADDR); + i2c_writel_dma((u32)i2c->dma_buf.paddr, i2c, + OFFSET_RX_MEM_ADDR); + i2c_writel_dma(i2c->msg_len, i2c, OFFSET_TX_LEN); + i2c_writel_dma(i2c->msg_aux_len, i2c, OFFSET_RX_LEN); + } + + /* flush before sending start */ + mb(); + i2c_writel_dma(I2C_DMA_START_EN, i2c, OFFSET_EN); + i2c_writew(I2C_TRANSAC_START, i2c, OFFSET_START); + + tmo = wait_event_timeout(i2c->wait, i2c->trans_stop, tmo); + if (tmo == 0) { + dev_dbg(i2c->dev, "addr: %x, transfer timeout\n", i2c->addr); + mtk_i2c_init_hw(i2c); + return -ETIMEDOUT; + } + + if (i2c->irq_stat & (I2C_HS_NACKERR | I2C_ACKERR)) { + dev_dbg(i2c->dev, "addr: %x, transfer ACK error\n", i2c->addr); + mtk_i2c_init_hw(i2c); + return -EREMOTEIO; + } + + dev_dbg(i2c->dev, "i2c transfer done.\n"); + + return 0; +} + +static inline void mtk_i2c_copy_to_dma(struct mtk_i2c *i2c, struct i2c_msg *msg) +{ + /* if the operate is write, need to copy the data to DMA memory */ + if (!(msg->flags & I2C_M_RD)) + memcpy(i2c->dma_buf.vaddr, msg->buf, msg->len); +} + +static inline void mtk_i2c_copy_from_dma(struct mtk_i2c *i2c, + struct i2c_msg *msg) +{ + /* if the operate is read, need to copy the data from DMA memory */ + if (msg->flags & I2C_M_RD) + memcpy(msg->buf, i2c->dma_buf.vaddr, msg->len); +} + +static int mtk_i2c_transfer(struct i2c_adapter *adap, + struct i2c_msg msgs[], int num) +{ + int ret; + struct mtk_i2c *i2c = i2c_get_adapdata(adap); + + ret = mtk_i2c_clock_enable(i2c); + if (ret) + return ret; + + if (msgs->addr == 0) { + dev_dbg(i2c->dev, " addr is invalid.\n"); + ret = -EINVAL; + goto err_exit; + } + + if (msgs->buf == NULL) { + dev_dbg(i2c->dev, " data buffer is NULL.\n"); + ret = -EINVAL; + goto err_exit; + } + + i2c->addr = msgs->addr; + i2c->msg_len = msgs->len; + i2c->msg_buf = msgs->buf; + + if (msgs->flags & I2C_M_RD) + i2c->op = I2C_MASTER_RD; + else + i2c->op = I2C_MASTER_WR; + + /* combined two messages into one transaction */ + if (num > 1) { + i2c->msg_aux_len = (msgs + 1)->len; + i2c->op = I2C_MASTER_WRRD; + } + + /* + * always use DMA mode. + * 1st when write need copy the data of message to dma memory + * 2nd when read need copy the DMA data to the message buffer. + */ + mtk_i2c_copy_to_dma(i2c, msgs); + i2c->msg_buf = (u8 *)i2c->dma_buf.paddr; + ret = mtk_i2c_do_transfer(i2c); + if (ret < 0) + goto err_exit; + + if (i2c->op == I2C_MASTER_WRRD) + mtk_i2c_copy_from_dma(i2c, msgs + 1); + else + mtk_i2c_copy_from_dma(i2c, msgs); + + /* the return value is number of executed messages */ + ret = num; + +err_exit: + mtk_i2c_clock_disable(i2c); + return ret; +} + +static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id) +{ + struct mtk_i2c *i2c = dev_id; + + /* Clear interrupt mask */ + i2c_writew(~(I2C_HS_NACKERR | I2C_ACKERR | I2C_TRANSAC_COMP), + i2c, OFFSET_INTR_MASK); + + i2c->irq_stat = i2c_readw(i2c, OFFSET_INTR_STAT); + i2c_writew(I2C_HS_NACKERR | I2C_ACKERR | I2C_TRANSAC_COMP, + i2c, OFFSET_INTR_STAT); + i2c->trans_stop = true; + wake_up(&i2c->wait); + + return IRQ_HANDLED; +} + +static u32 mtk_i2c_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SMBUS_EMUL; +} + +static const struct i2c_algorithm mtk_i2c_algorithm = { + .master_xfer = mtk_i2c_transfer, + .functionality = mtk_i2c_functionality, +}; + +static inline u32 mtk_get_device_prop(struct platform_device *pdev) +{ + const struct of_device_id *match; + + match = of_match_node(mtk_i2c_of_match, pdev->dev.of_node); + return (u32)match->data; +} + +static int mtk_i2c_parse_dt(struct device_node *np, struct mtk_i2c *i2c, + unsigned int *clk_src_div) +{ + i2c->speed_hz = I2C_DEFAUT_SPEED; + of_property_read_u32(np, "clock-frequency", &i2c->speed_hz); + of_property_read_u32(np, "clock-div", clk_src_div); + if (*clk_src_div == 0) + return -EINVAL; + + i2c->have_pmic = of_property_read_bool(np, "mediatek,have-pmic"); + i2c->use_push_pull = + of_property_read_bool(np, "mediatek,use-push-pull"); + + return 0; +} + +static const struct i2c_adapter_quirks mt6577_i2c_quirks = { + .flags = I2C_ADAPTER_QUIRK_COMB_WRITE_THEN_READ, + .max_num_msgs = 1, + .max_write_len = MAX_DMA_TRANS_SIZE, + .max_read_len = MAX_DMA_TRANS_SIZE, + .max_comb_write_len = MAX_DMA_TRANS_SIZE, + .max_comb_read_len = MAX_WRRD_TRANS_SIZE, +}; + +static int mtk_i2c_probe(struct platform_device *pdev) +{ + int ret = 0; + struct mtk_i2c *i2c; + unsigned int clk_src_in_hz; + unsigned int clk_src_div; + struct resource *res; + + i2c = devm_kzalloc(&pdev->dev, sizeof(struct mtk_i2c), GFP_KERNEL); + if (i2c == NULL) + return -ENOMEM; + + ret = mtk_i2c_parse_dt(pdev->dev.of_node, i2c, &clk_src_div); + if (ret) + return -EINVAL; + + i2c->platform_compat = mtk_get_device_prop(pdev); + if (i2c->have_pmic && (i2c->platform_compat & COMPAT_MT6577)) + return -EINVAL; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + + i2c->base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(i2c->base)) + return PTR_ERR(i2c->base); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + + i2c->pdmabase = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(i2c->pdmabase)) + return PTR_ERR(i2c->pdmabase); + + i2c->irqnr = platform_get_irq(pdev, 0); + if (i2c->irqnr <= 0) + return -EINVAL; + + ret = devm_request_irq(&pdev->dev, i2c->irqnr, mtk_i2c_irq, + IRQF_TRIGGER_NONE, I2C_DRV_NAME, i2c); + if (ret < 0) { + dev_err(&pdev->dev, + "Request I2C IRQ %d fail\n", i2c->irqnr); + return ret; + } + + i2c->adap.dev.of_node = pdev->dev.of_node; + i2c->dev = &i2c->adap.dev; + i2c->adap.dev.parent = &pdev->dev; + i2c->adap.owner = THIS_MODULE; + i2c->adap.algo = &mtk_i2c_algorithm; + i2c->adap.quirks = &mt6577_i2c_quirks; + i2c->adap.algo_data = NULL; + i2c->adap.timeout = 2 * HZ; + i2c->adap.retries = 1; + + i2c->clk_main = devm_clk_get(&pdev->dev, "main"); + if (IS_ERR(i2c->clk_main)) { + dev_err(&pdev->dev, "cannot get main clock\n"); + return PTR_ERR(i2c->clk_main); + } + + i2c->clk_dma = devm_clk_get(&pdev->dev, "dma"); + if (IS_ERR(i2c->clk_dma)) { + dev_err(&pdev->dev, "cannot get dma clock\n"); + return PTR_ERR(i2c->clk_dma); + } + + if (i2c->have_pmic) { + i2c->clk_pmic = devm_clk_get(&pdev->dev, "pmic"); + if (IS_ERR(i2c->clk_pmic)) { + dev_err(&pdev->dev, "cannot get pmic clock\n"); + return PTR_ERR(i2c->clk_pmic); + } + clk_src_in_hz = clk_get_rate(i2c->clk_pmic) / clk_src_div; + } else { + clk_src_in_hz = clk_get_rate(i2c->clk_main) / clk_src_div; + } + + dev_dbg(&pdev->dev, "clock source %p,clock src frequency %d\n", + i2c->clk_main, clk_src_in_hz); + strlcpy(i2c->adap.name, I2C_DRV_NAME, sizeof(i2c->adap.name)); + init_waitqueue_head(&i2c->wait); + + ret = i2c_set_speed(i2c, clk_src_in_hz); + if (ret) { + dev_err(&pdev->dev, "Failed to set the speed.\n"); + return -EINVAL; + } + + ret = mtk_i2c_clock_enable(i2c); + if (ret) { + dev_err(&pdev->dev, "clock enable failed!\n"); + return ret; + } + mtk_i2c_init_hw(i2c); + mtk_i2c_clock_disable(i2c); + + i2c->dma_buf.vaddr = dma_alloc_coherent(&pdev->dev, + PAGE_SIZE, &i2c->dma_buf.paddr, GFP_KERNEL); + if (i2c->dma_buf.vaddr == NULL) { + dev_err(&pdev->dev, "dma_alloc_coherent fail\n"); + return -ENOMEM; + } + + i2c_set_adapdata(&i2c->adap, i2c); + ret = i2c_add_adapter(&i2c->adap); + if (ret) { + dev_err(&pdev->dev, "Failed to add i2c bus to i2c core\n"); + free_i2c_dma_bufs(i2c); + return ret; + } + + platform_set_drvdata(pdev, i2c); + + return 0; +} + +static int mtk_i2c_remove(struct platform_device *pdev) +{ + struct mtk_i2c *i2c = platform_get_drvdata(pdev); + + i2c_del_adapter(&i2c->adap); + free_i2c_dma_bufs(i2c); + platform_set_drvdata(pdev, NULL); + + return 0; +} + +static struct platform_driver mtk_i2c_driver = { + .probe = mtk_i2c_probe, + .remove = mtk_i2c_remove, + .driver = { + .name = I2C_DRV_NAME, + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(mtk_i2c_of_match), + }, +}; + +module_platform_driver(mtk_i2c_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("MediaTek I2C Bus Driver"); +MODULE_AUTHOR("Xudong Chen ");