| /* |
| * Copyright (c) 2014 MediaTek Inc. |
| * Author: Xudong Chen <xudong.chen@mediatek.com> |
| * |
| * 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 <linux/clk.h> |
| #include <linux/completion.h> |
| #include <linux/delay.h> |
| #include <linux/device.h> |
| #include <linux/dma-mapping.h> |
| #include <linux/err.h> |
| #include <linux/errno.h> |
| #include <linux/i2c.h> |
| #include <linux/init.h> |
| #include <linux/interrupt.h> |
| #include <linux/io.h> |
| #include <linux/kernel.h> |
| #include <linux/mm.h> |
| #include <linux/module.h> |
| #include <linux/of_address.h> |
| #include <linux/of_irq.h> |
| #include <linux/platform_device.h> |
| #include <linux/scatterlist.h> |
| #include <linux/sched.h> |
| #include <linux/slab.h> |
| |
| #define I2C_RS_TRANSFER (1 << 4) |
| #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_RS_MUL_CNFG (1 << 15) |
| #define I2C_RS_MUL_TRIG (1 << 14) |
| #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_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_DMA_HARD_RST 0x0002 |
| #define I2C_DMA_4G_MODE 0x0001 |
| |
| #define I2C_DEFAULT_SPEED 100000 /* hz */ |
| #define MAX_FS_MODE_SPEED 400000 |
| #define MAX_HS_MODE_SPEED 3400000 |
| #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 I2C_DRV_NAME "i2c-mt65xx" |
| |
| enum DMA_REGS_OFFSET { |
| OFFSET_INT_FLAG = 0x0, |
| OFFSET_INT_EN = 0x04, |
| OFFSET_EN = 0x08, |
| OFFSET_RST = 0x0c, |
| OFFSET_CON = 0x18, |
| OFFSET_TX_MEM_ADDR = 0x1c, |
| OFFSET_RX_MEM_ADDR = 0x20, |
| OFFSET_TX_LEN = 0x24, |
| OFFSET_RX_LEN = 0x28, |
| OFFSET_TX_4G_MODE = 0x54, |
| OFFSET_RX_4G_MODE = 0x58, |
| }; |
| |
| enum i2c_trans_st_rs { |
| I2C_TRANS_STOP = 0, |
| I2C_TRANS_REPEATED_START, |
| }; |
| |
| 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_compatible { |
| const struct i2c_adapter_quirks *quirks; |
| unsigned char pmic_i2c: 1; |
| unsigned char dcm: 1; |
| unsigned char auto_restart: 1; |
| unsigned char aux_len_reg: 1; |
| unsigned char support_33bits: 1; |
| }; |
| |
| struct mtk_i2c { |
| struct i2c_adapter adap; /* i2c host adapter */ |
| struct device *dev; |
| struct completion msg_complete; |
| |
| /* set in i2c probe */ |
| void __iomem *base; /* i2c base addr */ |
| void __iomem *pdmabase; /* dma base address*/ |
| 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 */ |
| |
| u16 irq_stat; /* interrupt status */ |
| unsigned int clk_src_div; |
| unsigned int speed_hz; /* The speed in transfer */ |
| enum mtk_trans_op op; |
| u16 timing_reg; |
| u16 high_speed_reg; |
| unsigned char auto_restart; |
| bool ignore_restart_irq; |
| const struct mtk_i2c_compatible *dev_comp; |
| }; |
| |
| static const struct i2c_adapter_quirks mt6577_i2c_quirks = { |
| .flags = I2C_AQ_COMB_WRITE_THEN_READ, |
| .max_num_msgs = 1, |
| .max_write_len = 255, |
| .max_read_len = 255, |
| .max_comb_1st_msg_len = 255, |
| .max_comb_2nd_msg_len = 31, |
| }; |
| |
| static const struct mtk_i2c_compatible mt6577_compat = { |
| .quirks = &mt6577_i2c_quirks, |
| .pmic_i2c = 0, |
| .dcm = 1, |
| .auto_restart = 0, |
| .aux_len_reg = 0, |
| .support_33bits = 0, |
| }; |
| |
| static const struct mtk_i2c_compatible mt6589_compat = { |
| .quirks = &mt6577_i2c_quirks, |
| .pmic_i2c = 1, |
| .dcm = 0, |
| .auto_restart = 0, |
| .aux_len_reg = 0, |
| .support_33bits = 0, |
| }; |
| |
| static const struct mtk_i2c_compatible mt8173_compat = { |
| .pmic_i2c = 0, |
| .dcm = 1, |
| .auto_restart = 1, |
| .aux_len_reg = 1, |
| .support_33bits = 1, |
| }; |
| |
| static const struct of_device_id mtk_i2c_of_match[] = { |
| { .compatible = "mediatek,mt6577-i2c", .data = &mt6577_compat }, |
| { .compatible = "mediatek,mt6589-i2c", .data = &mt6589_compat }, |
| { .compatible = "mediatek,mt8173-i2c", .data = &mt8173_compat }, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(of, mtk_i2c_of_match); |
| |
| 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 mtk_i2c_init_hw(struct mtk_i2c *i2c) |
| { |
| u16 control_reg; |
| |
| writew(I2C_SOFT_RST, i2c->base + OFFSET_SOFTRESET); |
| |
| /* Set ioconfig */ |
| if (i2c->use_push_pull) |
| writew(I2C_IO_CONFIG_PUSH_PULL, i2c->base + OFFSET_IO_CONFIG); |
| else |
| writew(I2C_IO_CONFIG_OPEN_DRAIN, i2c->base + OFFSET_IO_CONFIG); |
| |
| if (i2c->dev_comp->dcm) |
| writew(I2C_DCM_DISABLE, i2c->base + OFFSET_DCM_EN); |
| |
| writew(i2c->timing_reg, i2c->base + OFFSET_TIMING); |
| writew(i2c->high_speed_reg, i2c->base + OFFSET_HS); |
| |
| /* If use i2c pin from PMIC mt6397 side, need set PATH_DIR first */ |
| if (i2c->have_pmic) |
| writew(I2C_CONTROL_WRAPPER, i2c->base + OFFSET_PATH_DIR); |
| |
| control_reg = I2C_CONTROL_ACKERR_DET_EN | |
| I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN; |
| writew(control_reg, i2c->base + OFFSET_CONTROL); |
| writew(I2C_DELAY_LEN, i2c->base + OFFSET_DELAY_LEN); |
| |
| writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST); |
| udelay(50); |
| writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST); |
| } |
| |
| /* |
| * Calculate i2c port speed |
| * |
| * Hardware design: |
| * i2c_bus_freq = parent_clk / (clock_div * 2 * sample_cnt * step_cnt) |
| * clock_div: fixed in hardware, but may be various in different SoCs |
| * |
| * The calculation want to pick the highest bus frequency that is still |
| * less than or equal to i2c->speed_hz. The calculation try to get |
| * sample_cnt and step_cn |
| */ |
| static int mtk_i2c_calculate_speed(struct mtk_i2c *i2c, unsigned int clk_src, |
| unsigned int target_speed, |
| unsigned int *timing_step_cnt, |
| unsigned int *timing_sample_cnt) |
| { |
| unsigned int step_cnt; |
| unsigned int sample_cnt; |
| unsigned int max_step_cnt; |
| unsigned int base_sample_cnt = MAX_SAMPLE_CNT_DIV; |
| unsigned int base_step_cnt; |
| unsigned int opt_div; |
| unsigned int best_mul; |
| unsigned int cnt_mul; |
| |
| if (target_speed > MAX_HS_MODE_SPEED) |
| target_speed = MAX_HS_MODE_SPEED; |
| |
| if (target_speed > MAX_FS_MODE_SPEED) |
| max_step_cnt = MAX_HS_STEP_CNT_DIV; |
| else |
| max_step_cnt = MAX_STEP_CNT_DIV; |
| |
| base_step_cnt = max_step_cnt; |
| /* Find the best combination */ |
| opt_div = DIV_ROUND_UP(clk_src >> 1, target_speed); |
| best_mul = MAX_SAMPLE_CNT_DIV * max_step_cnt; |
| |
| /* Search for the best pair (sample_cnt, step_cnt) with |
| * 0 < sample_cnt < MAX_SAMPLE_CNT_DIV |
| * 0 < step_cnt < max_step_cnt |
| * sample_cnt * step_cnt >= opt_div |
| * optimizing for sample_cnt * step_cnt being minimal |
| */ |
| for (sample_cnt = 1; sample_cnt <= MAX_SAMPLE_CNT_DIV; sample_cnt++) { |
| step_cnt = DIV_ROUND_UP(opt_div, sample_cnt); |
| cnt_mul = step_cnt * sample_cnt; |
| if (step_cnt > max_step_cnt) |
| continue; |
| |
| if (cnt_mul < best_mul) { |
| best_mul = cnt_mul; |
| base_sample_cnt = sample_cnt; |
| base_step_cnt = step_cnt; |
| if (best_mul == opt_div) |
| break; |
| } |
| } |
| |
| sample_cnt = base_sample_cnt; |
| step_cnt = base_step_cnt; |
| |
| if ((clk_src / (2 * sample_cnt * step_cnt)) > target_speed) { |
| /* In this case, hardware can't support such |
| * low i2c_bus_freq |
| */ |
| dev_dbg(i2c->dev, "Unsupported speed (%uhz)\n", target_speed); |
| return -EINVAL; |
| } |
| |
| *timing_step_cnt = step_cnt - 1; |
| *timing_sample_cnt = sample_cnt - 1; |
| |
| return 0; |
| } |
| |
| static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk) |
| { |
| unsigned int clk_src; |
| unsigned int step_cnt; |
| unsigned int sample_cnt; |
| unsigned int target_speed; |
| int ret; |
| |
| clk_src = parent_clk / i2c->clk_src_div; |
| target_speed = i2c->speed_hz; |
| |
| if (target_speed > MAX_FS_MODE_SPEED) { |
| /* Set master code speed register */ |
| ret = mtk_i2c_calculate_speed(i2c, clk_src, MAX_FS_MODE_SPEED, |
| &step_cnt, &sample_cnt); |
| if (ret < 0) |
| return ret; |
| |
| i2c->timing_reg = (sample_cnt << 8) | 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); |
| } 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; |
| } |
| |
| return 0; |
| } |
| |
| static inline u32 mtk_i2c_set_4g_mode(dma_addr_t addr) |
| { |
| return (addr & BIT_ULL(32)) ? I2C_DMA_4G_MODE : I2C_DMA_CLR_FLAG; |
| } |
| |
| static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, |
| int num, int left_num) |
| { |
| u16 addr_reg; |
| u16 start_reg; |
| u16 control_reg; |
| u16 restart_flag = 0; |
| u32 reg_4g_mode; |
| dma_addr_t rpaddr = 0; |
| dma_addr_t wpaddr = 0; |
| int ret; |
| |
| i2c->irq_stat = 0; |
| |
| if (i2c->auto_restart) |
| restart_flag = I2C_RS_TRANSFER; |
| |
| reinit_completion(&i2c->msg_complete); |
| |
| control_reg = readw(i2c->base + OFFSET_CONTROL) & |
| ~(I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS); |
| if ((i2c->speed_hz > 400000) || (left_num >= 1)) |
| control_reg |= I2C_CONTROL_RS; |
| |
| if (i2c->op == I2C_MASTER_WRRD) |
| control_reg |= I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS; |
| |
| writew(control_reg, i2c->base + OFFSET_CONTROL); |
| |
| /* set start condition */ |
| if (i2c->speed_hz <= 100000) |
| writew(I2C_ST_START_CON, i2c->base + OFFSET_EXT_CONF); |
| else |
| writew(I2C_FS_START_CON, i2c->base + OFFSET_EXT_CONF); |
| |
| addr_reg = i2c_8bit_addr_from_msg(msgs); |
| writew(addr_reg, i2c->base + OFFSET_SLAVE_ADDR); |
| |
| /* Clear interrupt status */ |
| writew(restart_flag | I2C_HS_NACKERR | I2C_ACKERR | |
| I2C_TRANSAC_COMP, i2c->base + OFFSET_INTR_STAT); |
| writew(I2C_FIFO_ADDR_CLR, i2c->base + OFFSET_FIFO_ADDR_CLR); |
| |
| /* Enable interrupt */ |
| writew(restart_flag | I2C_HS_NACKERR | I2C_ACKERR | |
| I2C_TRANSAC_COMP, i2c->base + OFFSET_INTR_MASK); |
| |
| /* Set transfer and transaction len */ |
| if (i2c->op == I2C_MASTER_WRRD) { |
| if (i2c->dev_comp->aux_len_reg) { |
| writew(msgs->len, i2c->base + OFFSET_TRANSFER_LEN); |
| writew((msgs + 1)->len, i2c->base + |
| OFFSET_TRANSFER_LEN_AUX); |
| } else { |
| writew(msgs->len | ((msgs + 1)->len) << 8, |
| i2c->base + OFFSET_TRANSFER_LEN); |
| } |
| writew(I2C_WRRD_TRANAC_VALUE, i2c->base + OFFSET_TRANSAC_LEN); |
| } else { |
| writew(msgs->len, i2c->base + OFFSET_TRANSFER_LEN); |
| writew(num, i2c->base + OFFSET_TRANSAC_LEN); |
| } |
| |
| /* Prepare buffer data to start transfer */ |
| if (i2c->op == I2C_MASTER_RD) { |
| writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG); |
| writel(I2C_DMA_CON_RX, i2c->pdmabase + OFFSET_CON); |
| rpaddr = dma_map_single(i2c->dev, msgs->buf, |
| msgs->len, DMA_FROM_DEVICE); |
| if (dma_mapping_error(i2c->dev, rpaddr)) |
| return -ENOMEM; |
| |
| if (i2c->dev_comp->support_33bits) { |
| reg_4g_mode = mtk_i2c_set_4g_mode(rpaddr); |
| writel(reg_4g_mode, i2c->pdmabase + OFFSET_RX_4G_MODE); |
| } |
| |
| writel((u32)rpaddr, i2c->pdmabase + OFFSET_RX_MEM_ADDR); |
| writel(msgs->len, i2c->pdmabase + OFFSET_RX_LEN); |
| } else if (i2c->op == I2C_MASTER_WR) { |
| writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG); |
| writel(I2C_DMA_CON_TX, i2c->pdmabase + OFFSET_CON); |
| wpaddr = dma_map_single(i2c->dev, msgs->buf, |
| msgs->len, DMA_TO_DEVICE); |
| if (dma_mapping_error(i2c->dev, wpaddr)) |
| return -ENOMEM; |
| |
| if (i2c->dev_comp->support_33bits) { |
| reg_4g_mode = mtk_i2c_set_4g_mode(wpaddr); |
| writel(reg_4g_mode, i2c->pdmabase + OFFSET_TX_4G_MODE); |
| } |
| |
| writel((u32)wpaddr, i2c->pdmabase + OFFSET_TX_MEM_ADDR); |
| writel(msgs->len, i2c->pdmabase + OFFSET_TX_LEN); |
| } else { |
| writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_INT_FLAG); |
| writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_CON); |
| wpaddr = dma_map_single(i2c->dev, msgs->buf, |
| msgs->len, DMA_TO_DEVICE); |
| if (dma_mapping_error(i2c->dev, wpaddr)) |
| return -ENOMEM; |
| rpaddr = dma_map_single(i2c->dev, (msgs + 1)->buf, |
| (msgs + 1)->len, |
| DMA_FROM_DEVICE); |
| if (dma_mapping_error(i2c->dev, rpaddr)) { |
| dma_unmap_single(i2c->dev, wpaddr, |
| msgs->len, DMA_TO_DEVICE); |
| return -ENOMEM; |
| } |
| |
| if (i2c->dev_comp->support_33bits) { |
| reg_4g_mode = mtk_i2c_set_4g_mode(wpaddr); |
| writel(reg_4g_mode, i2c->pdmabase + OFFSET_TX_4G_MODE); |
| |
| reg_4g_mode = mtk_i2c_set_4g_mode(rpaddr); |
| writel(reg_4g_mode, i2c->pdmabase + OFFSET_RX_4G_MODE); |
| } |
| |
| writel((u32)wpaddr, i2c->pdmabase + OFFSET_TX_MEM_ADDR); |
| writel((u32)rpaddr, i2c->pdmabase + OFFSET_RX_MEM_ADDR); |
| writel(msgs->len, i2c->pdmabase + OFFSET_TX_LEN); |
| writel((msgs + 1)->len, i2c->pdmabase + OFFSET_RX_LEN); |
| } |
| |
| writel(I2C_DMA_START_EN, i2c->pdmabase + OFFSET_EN); |
| |
| if (!i2c->auto_restart) { |
| start_reg = I2C_TRANSAC_START; |
| } else { |
| start_reg = I2C_TRANSAC_START | I2C_RS_MUL_TRIG; |
| if (left_num >= 1) |
| start_reg |= I2C_RS_MUL_CNFG; |
| } |
| writew(start_reg, i2c->base + OFFSET_START); |
| |
| ret = wait_for_completion_timeout(&i2c->msg_complete, |
| i2c->adap.timeout); |
| |
| /* Clear interrupt mask */ |
| writew(~(restart_flag | I2C_HS_NACKERR | I2C_ACKERR | |
| I2C_TRANSAC_COMP), i2c->base + OFFSET_INTR_MASK); |
| |
| if (i2c->op == I2C_MASTER_WR) { |
| dma_unmap_single(i2c->dev, wpaddr, |
| msgs->len, DMA_TO_DEVICE); |
| } else if (i2c->op == I2C_MASTER_RD) { |
| dma_unmap_single(i2c->dev, rpaddr, |
| msgs->len, DMA_FROM_DEVICE); |
| } else { |
| dma_unmap_single(i2c->dev, wpaddr, msgs->len, |
| DMA_TO_DEVICE); |
| dma_unmap_single(i2c->dev, rpaddr, (msgs + 1)->len, |
| DMA_FROM_DEVICE); |
| } |
| |
| if (ret == 0) { |
| dev_dbg(i2c->dev, "addr: %x, transfer timeout\n", msgs->addr); |
| mtk_i2c_init_hw(i2c); |
| return -ETIMEDOUT; |
| } |
| |
| completion_done(&i2c->msg_complete); |
| |
| if (i2c->irq_stat & (I2C_HS_NACKERR | I2C_ACKERR)) { |
| dev_dbg(i2c->dev, "addr: %x, transfer ACK error\n", msgs->addr); |
| mtk_i2c_init_hw(i2c); |
| return -ENXIO; |
| } |
| |
| return 0; |
| } |
| |
| static int mtk_i2c_transfer(struct i2c_adapter *adap, |
| struct i2c_msg msgs[], int num) |
| { |
| int ret; |
| int left_num = num; |
| struct mtk_i2c *i2c = i2c_get_adapdata(adap); |
| |
| ret = mtk_i2c_clock_enable(i2c); |
| if (ret) |
| return ret; |
| |
| i2c->auto_restart = i2c->dev_comp->auto_restart; |
| |
| /* checking if we can skip restart and optimize using WRRD mode */ |
| if (i2c->auto_restart && num == 2) { |
| if (!(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD) && |
| msgs[0].addr == msgs[1].addr) { |
| i2c->auto_restart = 0; |
| } |
| } |
| |
| if (i2c->auto_restart && num >= 2 && i2c->speed_hz > MAX_FS_MODE_SPEED) |
| /* ignore the first restart irq after the master code, |
| * otherwise the first transfer will be discarded. |
| */ |
| i2c->ignore_restart_irq = true; |
| else |
| i2c->ignore_restart_irq = false; |
| |
| while (left_num--) { |
| if (!msgs->buf) { |
| dev_dbg(i2c->dev, "data buffer is NULL.\n"); |
| ret = -EINVAL; |
| goto err_exit; |
| } |
| |
| if (msgs->flags & I2C_M_RD) |
| i2c->op = I2C_MASTER_RD; |
| else |
| i2c->op = I2C_MASTER_WR; |
| |
| if (!i2c->auto_restart) { |
| if (num > 1) { |
| /* combined two messages into one transaction */ |
| i2c->op = I2C_MASTER_WRRD; |
| left_num--; |
| } |
| } |
| |
| /* always use DMA mode. */ |
| ret = mtk_i2c_do_transfer(i2c, msgs, num, left_num); |
| if (ret < 0) |
| goto err_exit; |
| |
| 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; |
| u16 restart_flag = 0; |
| u16 intr_stat; |
| |
| if (i2c->auto_restart) |
| restart_flag = I2C_RS_TRANSFER; |
| |
| intr_stat = readw(i2c->base + OFFSET_INTR_STAT); |
| writew(intr_stat, i2c->base + OFFSET_INTR_STAT); |
| |
| /* |
| * when occurs ack error, i2c controller generate two interrupts |
| * first is the ack error interrupt, then the complete interrupt |
| * i2c->irq_stat need keep the two interrupt value. |
| */ |
| i2c->irq_stat |= intr_stat; |
| |
| if (i2c->ignore_restart_irq && (i2c->irq_stat & restart_flag)) { |
| i2c->ignore_restart_irq = false; |
| i2c->irq_stat = 0; |
| writew(I2C_RS_MUL_CNFG | I2C_RS_MUL_TRIG | I2C_TRANSAC_START, |
| i2c->base + OFFSET_START); |
| } else { |
| if (i2c->irq_stat & (I2C_TRANSAC_COMP | restart_flag)) |
| complete(&i2c->msg_complete); |
| } |
| |
| return IRQ_HANDLED; |
| } |
| |
| static u32 mtk_i2c_functionality(struct i2c_adapter *adap) |
| { |
| return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; |
| } |
| |
| static const struct i2c_algorithm mtk_i2c_algorithm = { |
| .master_xfer = mtk_i2c_transfer, |
| .functionality = mtk_i2c_functionality, |
| }; |
| |
| static int mtk_i2c_parse_dt(struct device_node *np, struct mtk_i2c *i2c) |
| { |
| int ret; |
| |
| ret = of_property_read_u32(np, "clock-frequency", &i2c->speed_hz); |
| if (ret < 0) |
| i2c->speed_hz = I2C_DEFAULT_SPEED; |
| |
| ret = of_property_read_u32(np, "clock-div", &i2c->clk_src_div); |
| if (ret < 0) |
| return ret; |
| |
| if (i2c->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 int mtk_i2c_probe(struct platform_device *pdev) |
| { |
| const struct of_device_id *of_id; |
| int ret = 0; |
| struct mtk_i2c *i2c; |
| struct clk *clk; |
| struct resource *res; |
| int irq; |
| |
| i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL); |
| if (!i2c) |
| return -ENOMEM; |
| |
| ret = mtk_i2c_parse_dt(pdev->dev.of_node, i2c); |
| if (ret) |
| 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); |
| |
| irq = platform_get_irq(pdev, 0); |
| if (irq <= 0) |
| return irq; |
| |
| init_completion(&i2c->msg_complete); |
| |
| of_id = of_match_node(mtk_i2c_of_match, pdev->dev.of_node); |
| if (!of_id) |
| return -EINVAL; |
| |
| i2c->dev_comp = of_id->data; |
| i2c->adap.dev.of_node = pdev->dev.of_node; |
| i2c->dev = &pdev->dev; |
| i2c->adap.dev.parent = &pdev->dev; |
| i2c->adap.owner = THIS_MODULE; |
| i2c->adap.algo = &mtk_i2c_algorithm; |
| i2c->adap.quirks = i2c->dev_comp->quirks; |
| i2c->adap.timeout = 2 * HZ; |
| i2c->adap.retries = 1; |
| |
| if (i2c->have_pmic && !i2c->dev_comp->pmic_i2c) |
| return -EINVAL; |
| |
| 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); |
| } |
| |
| clk = i2c->clk_main; |
| 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 = i2c->clk_pmic; |
| } |
| |
| strlcpy(i2c->adap.name, I2C_DRV_NAME, sizeof(i2c->adap.name)); |
| |
| ret = mtk_i2c_set_speed(i2c, clk_get_rate(clk)); |
| if (ret) { |
| dev_err(&pdev->dev, "Failed to set the speed.\n"); |
| return -EINVAL; |
| } |
| |
| if (i2c->dev_comp->support_33bits) { |
| ret = dma_set_mask(&pdev->dev, DMA_BIT_MASK(33)); |
| if (ret) { |
| dev_err(&pdev->dev, "dma_set_mask return error.\n"); |
| return ret; |
| } |
| } |
| |
| 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); |
| |
| ret = devm_request_irq(&pdev->dev, irq, mtk_i2c_irq, |
| IRQF_TRIGGER_NONE, I2C_DRV_NAME, i2c); |
| if (ret < 0) { |
| dev_err(&pdev->dev, |
| "Request I2C IRQ %d fail\n", irq); |
| return ret; |
| } |
| |
| i2c_set_adapdata(&i2c->adap, i2c); |
| ret = i2c_add_adapter(&i2c->adap); |
| if (ret) |
| 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); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| static int mtk_i2c_resume(struct device *dev) |
| { |
| struct mtk_i2c *i2c = dev_get_drvdata(dev); |
| |
| mtk_i2c_init_hw(i2c); |
| |
| return 0; |
| } |
| #endif |
| |
| static const struct dev_pm_ops mtk_i2c_pm = { |
| SET_SYSTEM_SLEEP_PM_OPS(NULL, mtk_i2c_resume) |
| }; |
| |
| static struct platform_driver mtk_i2c_driver = { |
| .probe = mtk_i2c_probe, |
| .remove = mtk_i2c_remove, |
| .driver = { |
| .name = I2C_DRV_NAME, |
| .pm = &mtk_i2c_pm, |
| .of_match_table = of_match_ptr(mtk_i2c_of_match), |
| }, |
| }; |
| |
| module_platform_driver(mtk_i2c_driver); |
| |
| MODULE_LICENSE("GPL v2"); |
| MODULE_DESCRIPTION("MediaTek I2C Bus Driver"); |
| MODULE_AUTHOR("Xudong Chen <xudong.chen@mediatek.com>"); |