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Release 4.7 drivers/i2c/busses/i2c-mt65xx.c

/*
 * 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_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_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 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 i2c_adapter_quirks mt8173_i2c_quirks = {
	.max_num_msgs = 65535,
	.max_write_len = 65535,
	.max_read_len = 65535,
	.max_comb_1st_msg_len = 65535,
	.max_comb_2nd_msg_len = 65535,
};


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 = {
	.quirks = &mt8173_i2c_quirks,
	.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; }

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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); }

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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); }

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/* * 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_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk, unsigned int clock_div) { unsigned int clk_src; unsigned int step_cnt; unsigned int sample_cnt; unsigned int max_step_cnt; unsigned int target_speed; 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; clk_src = parent_clk / clock_div; target_speed = i2c->speed_hz; 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; } step_cnt--; sample_cnt--; if (target_speed > MAX_FS_MODE_SPEED) { /* Set the high speed mode register */ i2c->timing_reg = I2C_FS_TIME_INIT_VALUE; i2c->high_speed_reg = I2C_TIME_DEFAULT_VALUE | (sample_cnt << 12) | (step_cnt << 8); } else { i2c->timing_reg = (sample_cnt << 8) | (step_cnt << 0); /* Disable the high speed transaction */ i2c->high_speed_reg = I2C_TIME_CLR_VALUE; } return 0; }

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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; }

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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; }

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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; }

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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; }

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static u32 mtk_i2c_functionality(struct i2c_adapter *adap) { return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; }

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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, unsigned int *clk_src_div) { 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", clk_src_div); if (ret < 0) return ret; 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; }

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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; unsigned int clk_src_div; 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, &clk_src_div); 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), clk_src_div); 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) { dev_err(&pdev->dev, "Failed to add i2c bus to i2c core\n"); return ret; } platform_set_drvdata(pdev, i2c); return 0; }

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static int mtk_i2c_remove(struct platform_device *pdev) { struct mtk_i2c *i2c = platform_get_drvdata(pdev); i2c_del_adapter(&i2c->adap); return 0; }

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#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; }

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#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>");

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Total3871100.00%9100.00%
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