--- /dev/null
+/*
+ * Ingenic JZ4780 I2C bus driver
+ *
+ * Copyright (C) 2006 - 2009 Ingenic Semiconductor Inc.
+ * Copyright (C) 2015 Imagination Technologies
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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/bitops.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.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/module.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+
+#define JZ4780_I2C_CTRL 0x00
+#define JZ4780_I2C_TAR 0x04
+#define JZ4780_I2C_SAR 0x08
+#define JZ4780_I2C_DC 0x10
+#define JZ4780_I2C_SHCNT 0x14
+#define JZ4780_I2C_SLCNT 0x18
+#define JZ4780_I2C_FHCNT 0x1C
+#define JZ4780_I2C_FLCNT 0x20
+#define JZ4780_I2C_INTST 0x2C
+#define JZ4780_I2C_INTM 0x30
+#define JZ4780_I2C_RXTL 0x38
+#define JZ4780_I2C_TXTL 0x3C
+#define JZ4780_I2C_CINTR 0x40
+#define JZ4780_I2C_CRXUF 0x44
+#define JZ4780_I2C_CRXOF 0x48
+#define JZ4780_I2C_CTXOF 0x4C
+#define JZ4780_I2C_CRXREQ 0x50
+#define JZ4780_I2C_CTXABRT 0x54
+#define JZ4780_I2C_CRXDONE 0x58
+#define JZ4780_I2C_CACT 0x5C
+#define JZ4780_I2C_CSTP 0x60
+#define JZ4780_I2C_CSTT 0x64
+#define JZ4780_I2C_CGC 0x68
+#define JZ4780_I2C_ENB 0x6C
+#define JZ4780_I2C_STA 0x70
+#define JZ4780_I2C_TXABRT 0x80
+#define JZ4780_I2C_DMACR 0x88
+#define JZ4780_I2C_DMATDLR 0x8C
+#define JZ4780_I2C_DMARDLR 0x90
+#define JZ4780_I2C_SDASU 0x94
+#define JZ4780_I2C_ACKGC 0x98
+#define JZ4780_I2C_ENSTA 0x9C
+#define JZ4780_I2C_SDAHD 0xD0
+
+#define JZ4780_I2C_CTRL_STPHLD BIT(7)
+#define JZ4780_I2C_CTRL_SLVDIS BIT(6)
+#define JZ4780_I2C_CTRL_REST BIT(5)
+#define JZ4780_I2C_CTRL_MATP BIT(4)
+#define JZ4780_I2C_CTRL_SATP BIT(3)
+#define JZ4780_I2C_CTRL_SPDF BIT(2)
+#define JZ4780_I2C_CTRL_SPDS BIT(1)
+#define JZ4780_I2C_CTRL_MD BIT(0)
+
+#define JZ4780_I2C_STA_SLVACT BIT(6)
+#define JZ4780_I2C_STA_MSTACT BIT(5)
+#define JZ4780_I2C_STA_RFF BIT(4)
+#define JZ4780_I2C_STA_RFNE BIT(3)
+#define JZ4780_I2C_STA_TFE BIT(2)
+#define JZ4780_I2C_STA_TFNF BIT(1)
+#define JZ4780_I2C_STA_ACT BIT(0)
+
+static const char * const jz4780_i2c_abrt_src[] = {
+ "ABRT_7B_ADDR_NOACK",
+ "ABRT_10ADDR1_NOACK",
+ "ABRT_10ADDR2_NOACK",
+ "ABRT_XDATA_NOACK",
+ "ABRT_GCALL_NOACK",
+ "ABRT_GCALL_READ",
+ "ABRT_HS_ACKD",
+ "SBYTE_ACKDET",
+ "ABRT_HS_NORSTRT",
+ "SBYTE_NORSTRT",
+ "ABRT_10B_RD_NORSTRT",
+ "ABRT_MASTER_DIS",
+ "ARB_LOST",
+ "SLVFLUSH_TXFIFO",
+ "SLV_ARBLOST",
+ "SLVRD_INTX",
+};
+
+#define JZ4780_I2C_INTST_IGC BIT(11)
+#define JZ4780_I2C_INTST_ISTT BIT(10)
+#define JZ4780_I2C_INTST_ISTP BIT(9)
+#define JZ4780_I2C_INTST_IACT BIT(8)
+#define JZ4780_I2C_INTST_RXDN BIT(7)
+#define JZ4780_I2C_INTST_TXABT BIT(6)
+#define JZ4780_I2C_INTST_RDREQ BIT(5)
+#define JZ4780_I2C_INTST_TXEMP BIT(4)
+#define JZ4780_I2C_INTST_TXOF BIT(3)
+#define JZ4780_I2C_INTST_RXFL BIT(2)
+#define JZ4780_I2C_INTST_RXOF BIT(1)
+#define JZ4780_I2C_INTST_RXUF BIT(0)
+
+#define JZ4780_I2C_INTM_MIGC BIT(11)
+#define JZ4780_I2C_INTM_MISTT BIT(10)
+#define JZ4780_I2C_INTM_MISTP BIT(9)
+#define JZ4780_I2C_INTM_MIACT BIT(8)
+#define JZ4780_I2C_INTM_MRXDN BIT(7)
+#define JZ4780_I2C_INTM_MTXABT BIT(6)
+#define JZ4780_I2C_INTM_MRDREQ BIT(5)
+#define JZ4780_I2C_INTM_MTXEMP BIT(4)
+#define JZ4780_I2C_INTM_MTXOF BIT(3)
+#define JZ4780_I2C_INTM_MRXFL BIT(2)
+#define JZ4780_I2C_INTM_MRXOF BIT(1)
+#define JZ4780_I2C_INTM_MRXUF BIT(0)
+
+#define JZ4780_I2C_DC_READ BIT(8)
+
+#define JZ4780_I2C_SDAHD_HDENB BIT(8)
+
+#define JZ4780_I2C_ENB_I2C BIT(0)
+
+#define JZ4780_I2CSHCNT_ADJUST(n) (((n) - 8) < 6 ? 6 : ((n) - 8))
+#define JZ4780_I2CSLCNT_ADJUST(n) (((n) - 1) < 8 ? 8 : ((n) - 1))
+#define JZ4780_I2CFHCNT_ADJUST(n) (((n) - 8) < 6 ? 6 : ((n) - 8))
+#define JZ4780_I2CFLCNT_ADJUST(n) (((n) - 1) < 8 ? 8 : ((n) - 1))
+
+#define JZ4780_I2C_FIFO_LEN 16
+#define TX_LEVEL 3
+#define RX_LEVEL (JZ4780_I2C_FIFO_LEN - TX_LEVEL - 1)
+
+#define JZ4780_I2C_TIMEOUT 300
+
+#define BUFSIZE 200
+
+struct jz4780_i2c {
+ void __iomem *iomem;
+ int irq;
+ struct clk *clk;
+ struct i2c_adapter adap;
+
+ /* lock to protect rbuf and wbuf between xfer_rd/wr and irq handler */
+ spinlock_t lock;
+
+ /* beginning of lock scope */
+ unsigned char *rbuf;
+ int rd_total_len;
+ int rd_data_xfered;
+ int rd_cmd_xfered;
+
+ unsigned char *wbuf;
+ int wt_len;
+
+ int is_write;
+ int stop_hold;
+ int speed;
+
+ int data_buf[BUFSIZE];
+ int cmd_buf[BUFSIZE];
+ int cmd;
+
+ /* end of lock scope */
+ struct completion trans_waitq;
+};
+
+static inline unsigned short jz4780_i2c_readw(struct jz4780_i2c *i2c,
+ unsigned long offset)
+{
+ return readw(i2c->iomem + offset);
+}
+
+static inline void jz4780_i2c_writew(struct jz4780_i2c *i2c,
+ unsigned long offset, unsigned short val)
+{
+ writew(val, i2c->iomem + offset);
+}
+
+static int jz4780_i2c_disable(struct jz4780_i2c *i2c)
+{
+ unsigned short regval;
+ unsigned long loops = 5;
+
+ jz4780_i2c_writew(i2c, JZ4780_I2C_ENB, 0);
+
+ do {
+ regval = jz4780_i2c_readw(i2c, JZ4780_I2C_ENSTA);
+ if (!(regval & JZ4780_I2C_ENB_I2C))
+ return 0;
+
+ usleep_range(5000, 15000);
+ } while (--loops);
+
+ dev_err(&i2c->adap.dev, "disable failed: ENSTA=0x%04x\n", regval);
+ return -ETIMEDOUT;
+}
+
+static int jz4780_i2c_enable(struct jz4780_i2c *i2c)
+{
+ unsigned short regval;
+ unsigned long loops = 5;
+
+ jz4780_i2c_writew(i2c, JZ4780_I2C_ENB, 1);
+
+ do {
+ regval = jz4780_i2c_readw(i2c, JZ4780_I2C_ENSTA);
+ if (regval & JZ4780_I2C_ENB_I2C)
+ return 0;
+
+ usleep_range(5000, 15000);
+ } while (--loops);
+
+ dev_err(&i2c->adap.dev, "enable failed: ENSTA=0x%04x\n", regval);
+ return -ETIMEDOUT;
+}
+
+static int jz4780_i2c_set_target(struct jz4780_i2c *i2c, unsigned char address)
+{
+ unsigned short regval;
+ unsigned long loops = 5;
+
+ do {
+ regval = jz4780_i2c_readw(i2c, JZ4780_I2C_STA);
+ if ((regval & JZ4780_I2C_STA_TFE) &&
+ !(regval & JZ4780_I2C_STA_MSTACT))
+ break;
+
+ usleep_range(5000, 15000);
+ } while (--loops);
+
+ if (loops) {
+ jz4780_i2c_writew(i2c, JZ4780_I2C_TAR, address);
+ return 0;
+ }
+
+ dev_err(&i2c->adap.dev,
+ "set device to address 0x%02x failed, STA=0x%04x\n",
+ address, regval);
+
+ return -ENXIO;
+}
+
+static int jz4780_i2c_set_speed(struct jz4780_i2c *i2c)
+{
+ int dev_clk_khz = clk_get_rate(i2c->clk) / 1000;
+ int cnt_high = 0; /* HIGH period count of the SCL clock */
+ int cnt_low = 0; /* LOW period count of the SCL clock */
+ int cnt_period = 0; /* period count of the SCL clock */
+ int setup_time = 0;
+ int hold_time = 0;
+ unsigned short tmp = 0;
+ int i2c_clk = i2c->speed;
+
+ if (jz4780_i2c_disable(i2c))
+ dev_dbg(&i2c->adap.dev, "i2c not disabled\n");
+
+ /*
+ * 1 JZ4780_I2C cycle equals to cnt_period PCLK(i2c_clk)
+ * standard mode, min LOW and HIGH period are 4700 ns and 4000 ns
+ * fast mode, min LOW and HIGH period are 1300 ns and 600 ns
+ */
+ cnt_period = dev_clk_khz / i2c_clk;
+
+ if (i2c_clk <= 100)
+ cnt_high = (cnt_period * 4000) / (4700 + 4000);
+ else
+ cnt_high = (cnt_period * 600) / (1300 + 600);
+
+ cnt_low = cnt_period - cnt_high;
+
+ /*
+ * NOTE: JZ4780_I2C_CTRL_REST can't set when i2c enabled, because
+ * normal read are 2 messages, we cannot disable i2c controller
+ * between these two messages, this means that we must always set
+ * JZ4780_I2C_CTRL_REST when init JZ4780_I2C_CTRL
+ *
+ */
+ if (i2c_clk <= 100) {
+ tmp = JZ4780_I2C_CTRL_SPDS | JZ4780_I2C_CTRL_REST
+ | JZ4780_I2C_CTRL_SLVDIS | JZ4780_I2C_CTRL_MD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+
+ jz4780_i2c_writew(i2c, JZ4780_I2C_SHCNT,
+ JZ4780_I2CSHCNT_ADJUST(cnt_high));
+ jz4780_i2c_writew(i2c, JZ4780_I2C_SLCNT,
+ JZ4780_I2CSLCNT_ADJUST(cnt_low));
+ } else {
+ tmp = JZ4780_I2C_CTRL_SPDF | JZ4780_I2C_CTRL_REST
+ | JZ4780_I2C_CTRL_SLVDIS | JZ4780_I2C_CTRL_MD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+
+ jz4780_i2c_writew(i2c, JZ4780_I2C_FHCNT,
+ JZ4780_I2CFHCNT_ADJUST(cnt_high));
+ jz4780_i2c_writew(i2c, JZ4780_I2C_FLCNT,
+ JZ4780_I2CFLCNT_ADJUST(cnt_low));
+ }
+
+ /*
+ * a i2c device must internally provide a hold time at least 300ns
+ * tHD:DAT
+ * Standard Mode: min=300ns, max=3450ns
+ * Fast Mode: min=0ns, max=900ns
+ * tSU:DAT
+ * Standard Mode: min=250ns, max=infinite
+ * Fast Mode: min=100(250ns is recommended), max=infinite
+ *
+ * 1i2c_clk = 10^6 / dev_clk_khz
+ * on FPGA, dev_clk_khz = 12000, so 1i2c_clk = 1000/12 = 83ns
+ * on Pisces(1008M), dev_clk_khz=126000, so 1i2c_clk = 1000 / 126 = 8ns
+ *
+ * The actual hold time is (SDAHD + 1) * (i2c_clk period).
+ *
+ * Length of setup time calculated using (SDASU - 1) * (ic_clk_period)
+ *
+ */
+ if (i2c_clk <= 100) { /* standard mode */
+ setup_time = 300;
+ hold_time = 400;
+ } else {
+ setup_time = 450;
+ hold_time = 450;
+ }
+
+ hold_time = ((hold_time * dev_clk_khz) / 1000000) - 1;
+ setup_time = ((setup_time * dev_clk_khz) / 1000000) + 1;
+
+ if (setup_time > 255)
+ setup_time = 255;
+
+ if (setup_time <= 0)
+ setup_time = 1;
+
+ jz4780_i2c_writew(i2c, JZ4780_I2C_SDASU, setup_time);
+
+ if (hold_time > 255)
+ hold_time = 255;
+
+ if (hold_time >= 0) {
+ /*i2c hold time enable */
+ hold_time |= JZ4780_I2C_SDAHD_HDENB;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_SDAHD, hold_time);
+ } else {
+ /* disable hold time */
+ jz4780_i2c_writew(i2c, JZ4780_I2C_SDAHD, 0);
+ }
+
+ return 0;
+}
+
+static int jz4780_i2c_cleanup(struct jz4780_i2c *i2c)
+{
+ int ret;
+ unsigned long flags;
+ unsigned short tmp;
+
+ spin_lock_irqsave(&i2c->lock, flags);
+
+ /* can send stop now if need */
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
+ tmp &= ~JZ4780_I2C_CTRL_STPHLD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+
+ /* disable all interrupts first */
+ jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, 0);
+
+ /* then clear all interrupts */
+ jz4780_i2c_readw(i2c, JZ4780_I2C_CTXABRT);
+ jz4780_i2c_readw(i2c, JZ4780_I2C_CINTR);
+
+ /* then disable the controller */
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
+ tmp &= ~JZ4780_I2C_ENB_I2C;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+ udelay(10);
+ tmp |= JZ4780_I2C_ENB_I2C;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+
+ spin_unlock_irqrestore(&i2c->lock, flags);
+
+ ret = jz4780_i2c_disable(i2c);
+ if (ret)
+ dev_err(&i2c->adap.dev,
+ "unable to disable device during cleanup!\n");
+
+ if (unlikely(jz4780_i2c_readw(i2c, JZ4780_I2C_INTM)
+ & jz4780_i2c_readw(i2c, JZ4780_I2C_INTST)))
+ dev_err(&i2c->adap.dev,
+ "device has interrupts after a complete cleanup!\n");
+
+ return ret;
+}
+
+static int jz4780_i2c_prepare(struct jz4780_i2c *i2c)
+{
+ jz4780_i2c_set_speed(i2c);
+ return jz4780_i2c_enable(i2c);
+}
+
+static void jz4780_i2c_send_rcmd(struct jz4780_i2c *i2c, int cmd_count)
+{
+ int i;
+
+ for (i = 0; i < cmd_count; i++)
+ jz4780_i2c_writew(i2c, JZ4780_I2C_DC, JZ4780_I2C_DC_READ);
+}
+
+static void jz4780_i2c_trans_done(struct jz4780_i2c *i2c)
+{
+ jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, 0);
+ complete(&i2c->trans_waitq);
+}
+
+static irqreturn_t jz4780_i2c_irq(int irqno, void *dev_id)
+{
+ unsigned short tmp;
+ unsigned short intst;
+ unsigned short intmsk;
+ struct jz4780_i2c *i2c = dev_id;
+ unsigned long flags;
+
+ spin_lock_irqsave(&i2c->lock, flags);
+ intmsk = jz4780_i2c_readw(i2c, JZ4780_I2C_INTM);
+ intst = jz4780_i2c_readw(i2c, JZ4780_I2C_INTST);
+
+ intst &= intmsk;
+
+ if (intst & JZ4780_I2C_INTST_TXABT) {
+ jz4780_i2c_trans_done(i2c);
+ goto done;
+ }
+
+ if (intst & JZ4780_I2C_INTST_RXOF) {
+ dev_dbg(&i2c->adap.dev, "received fifo overflow!\n");
+ jz4780_i2c_trans_done(i2c);
+ goto done;
+ }
+
+ /*
+ * When reading, always drain RX FIFO before we send more Read
+ * Commands to avoid fifo overrun
+ */
+ if (i2c->is_write == 0) {
+ int rd_left;
+
+ while ((jz4780_i2c_readw(i2c, JZ4780_I2C_STA)
+ & JZ4780_I2C_STA_RFNE)) {
+ *(i2c->rbuf++) = jz4780_i2c_readw(i2c, JZ4780_I2C_DC)
+ & 0xff;
+ i2c->rd_data_xfered++;
+ if (i2c->rd_data_xfered == i2c->rd_total_len) {
+ jz4780_i2c_trans_done(i2c);
+ goto done;
+ }
+ }
+
+ rd_left = i2c->rd_total_len - i2c->rd_data_xfered;
+
+ if (rd_left <= JZ4780_I2C_FIFO_LEN)
+ jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, rd_left - 1);
+ }
+
+ if (intst & JZ4780_I2C_INTST_TXEMP) {
+ if (i2c->is_write == 0) {
+ int cmd_left = i2c->rd_total_len - i2c->rd_cmd_xfered;
+ int max_send = (JZ4780_I2C_FIFO_LEN - 1)
+ - (i2c->rd_cmd_xfered
+ - i2c->rd_data_xfered);
+ int cmd_to_send = min(cmd_left, max_send);
+
+ if (i2c->rd_cmd_xfered != 0)
+ cmd_to_send = min(cmd_to_send,
+ JZ4780_I2C_FIFO_LEN
+ - TX_LEVEL - 1);
+
+ if (cmd_to_send) {
+ jz4780_i2c_send_rcmd(i2c, cmd_to_send);
+ i2c->rd_cmd_xfered += cmd_to_send;
+ }
+
+ cmd_left = i2c->rd_total_len - i2c->rd_cmd_xfered;
+ if (cmd_left == 0) {
+ intmsk = jz4780_i2c_readw(i2c, JZ4780_I2C_INTM);
+ intmsk &= ~JZ4780_I2C_INTM_MTXEMP;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, intmsk);
+
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
+ tmp &= ~JZ4780_I2C_CTRL_STPHLD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+ }
+ } else {
+ unsigned short data;
+ unsigned short i2c_sta;
+
+ i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA);
+
+ while ((i2c_sta & JZ4780_I2C_STA_TFNF) &&
+ (i2c->wt_len > 0)) {
+ i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA);
+ data = *i2c->wbuf;
+ data &= ~JZ4780_I2C_DC_READ;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_DC,
+ data);
+ i2c->wbuf++;
+ i2c->wt_len--;
+ }
+
+ if (i2c->wt_len == 0) {
+ if (!i2c->stop_hold) {
+ tmp = jz4780_i2c_readw(i2c,
+ JZ4780_I2C_CTRL);
+ tmp &= ~JZ4780_I2C_CTRL_STPHLD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL,
+ tmp);
+ }
+
+ jz4780_i2c_trans_done(i2c);
+ goto done;
+ }
+ }
+ }
+
+done:
+ spin_unlock_irqrestore(&i2c->lock, flags);
+ return IRQ_HANDLED;
+}
+
+static void jz4780_i2c_txabrt(struct jz4780_i2c *i2c, int src)
+{
+ int i;
+
+ dev_err(&i2c->adap.dev, "txabrt: 0x%08x\n", src);
+ dev_err(&i2c->adap.dev, "device addr=%x\n",
+ jz4780_i2c_readw(i2c, JZ4780_I2C_TAR));
+ dev_err(&i2c->adap.dev, "send cmd count:%d %d\n",
+ i2c->cmd, i2c->cmd_buf[i2c->cmd]);
+ dev_err(&i2c->adap.dev, "receive data count:%d %d\n",
+ i2c->cmd, i2c->data_buf[i2c->cmd]);
+
+ for (i = 0; i < 16; i++) {
+ if (src & BIT(i))
+ dev_dbg(&i2c->adap.dev, "I2C TXABRT[%d]=%s\n",
+ i, jz4780_i2c_abrt_src[i]);
+ }
+}
+
+static inline int jz4780_i2c_xfer_read(struct jz4780_i2c *i2c,
+ unsigned char *buf, int len, int cnt,
+ int idx)
+{
+ int ret = 0;
+ long timeout;
+ int wait_time = JZ4780_I2C_TIMEOUT * (len + 5);
+ unsigned short tmp;
+ unsigned long flags;
+
+ memset(buf, 0, len);
+
+ spin_lock_irqsave(&i2c->lock, flags);
+
+ i2c->stop_hold = 0;
+ i2c->is_write = 0;
+ i2c->rbuf = buf;
+ i2c->rd_total_len = len;
+ i2c->rd_data_xfered = 0;
+ i2c->rd_cmd_xfered = 0;
+
+ if (len <= JZ4780_I2C_FIFO_LEN)
+ jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, len - 1);
+ else
+ jz4780_i2c_writew(i2c, JZ4780_I2C_RXTL, RX_LEVEL);
+
+ jz4780_i2c_writew(i2c, JZ4780_I2C_TXTL, TX_LEVEL);
+
+ jz4780_i2c_writew(i2c, JZ4780_I2C_INTM,
+ JZ4780_I2C_INTM_MRXFL | JZ4780_I2C_INTM_MTXEMP
+ | JZ4780_I2C_INTM_MTXABT | JZ4780_I2C_INTM_MRXOF);
+
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
+ tmp |= JZ4780_I2C_CTRL_STPHLD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+
+ spin_unlock_irqrestore(&i2c->lock, flags);
+
+ timeout = wait_for_completion_timeout(&i2c->trans_waitq,
+ msecs_to_jiffies(wait_time));
+
+ if (!timeout) {
+ dev_err(&i2c->adap.dev, "irq read timeout\n");
+ dev_dbg(&i2c->adap.dev, "send cmd count:%d %d\n",
+ i2c->cmd, i2c->cmd_buf[i2c->cmd]);
+ dev_dbg(&i2c->adap.dev, "receive data count:%d %d\n",
+ i2c->cmd, i2c->data_buf[i2c->cmd]);
+ ret = -EIO;
+ }
+
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_TXABRT);
+ if (tmp) {
+ jz4780_i2c_txabrt(i2c, tmp);
+ ret = -EIO;
+ }
+
+ return ret;
+}
+
+static inline int jz4780_i2c_xfer_write(struct jz4780_i2c *i2c,
+ unsigned char *buf, int len,
+ int cnt, int idx)
+{
+ int ret = 0;
+ int wait_time = JZ4780_I2C_TIMEOUT * (len + 5);
+ long timeout;
+ unsigned short tmp;
+ unsigned long flags;
+
+ spin_lock_irqsave(&i2c->lock, flags);
+
+ if (idx < (cnt - 1))
+ i2c->stop_hold = 1;
+ else
+ i2c->stop_hold = 0;
+
+ i2c->is_write = 1;
+ i2c->wbuf = buf;
+ i2c->wt_len = len;
+
+ jz4780_i2c_writew(i2c, JZ4780_I2C_TXTL, TX_LEVEL);
+
+ jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, JZ4780_I2C_INTM_MTXEMP
+ | JZ4780_I2C_INTM_MTXABT);
+
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
+ tmp |= JZ4780_I2C_CTRL_STPHLD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+
+ spin_unlock_irqrestore(&i2c->lock, flags);
+
+ timeout = wait_for_completion_timeout(&i2c->trans_waitq,
+ msecs_to_jiffies(wait_time));
+ if (timeout && !i2c->stop_hold) {
+ unsigned short i2c_sta;
+ int write_in_process;
+
+ timeout = JZ4780_I2C_TIMEOUT * 100;
+ for (; timeout > 0; timeout--) {
+ i2c_sta = jz4780_i2c_readw(i2c, JZ4780_I2C_STA);
+
+ write_in_process = (i2c_sta & JZ4780_I2C_STA_MSTACT) ||
+ !(i2c_sta & JZ4780_I2C_STA_TFE);
+ if (!write_in_process)
+ break;
+ udelay(10);
+ }
+ }
+
+ if (!timeout) {
+ dev_err(&i2c->adap.dev, "write wait timeout\n");
+ ret = -EIO;
+ }
+
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_TXABRT);
+ if (tmp) {
+ jz4780_i2c_txabrt(i2c, tmp);
+ ret = -EIO;
+ }
+
+ return ret;
+}
+
+static int jz4780_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msg,
+ int count)
+{
+ int i = -EIO;
+ int ret = 0;
+ struct jz4780_i2c *i2c = adap->algo_data;
+
+ ret = jz4780_i2c_prepare(i2c);
+ if (ret) {
+ dev_err(&i2c->adap.dev, "I2C prepare failed\n");
+ goto out;
+ }
+
+ if (msg->addr != jz4780_i2c_readw(i2c, JZ4780_I2C_TAR)) {
+ ret = jz4780_i2c_set_target(i2c, msg->addr);
+ if (ret)
+ goto out;
+ }
+ for (i = 0; i < count; i++, msg++) {
+ if (msg->flags & I2C_M_RD)
+ ret = jz4780_i2c_xfer_read(i2c, msg->buf, msg->len,
+ count, i);
+ else
+ ret = jz4780_i2c_xfer_write(i2c, msg->buf, msg->len,
+ count, i);
+
+ if (ret)
+ goto out;
+ }
+
+ ret = i;
+
+out:
+ jz4780_i2c_cleanup(i2c);
+ return ret;
+}
+
+static u32 jz4780_i2c_functionality(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm jz4780_i2c_algorithm = {
+ .master_xfer = jz4780_i2c_xfer,
+ .functionality = jz4780_i2c_functionality,
+};
+
+static const struct of_device_id jz4780_i2c_of_matches[] = {
+ { .compatible = "ingenic,jz4780-i2c", },
+ { /* sentinel */ }
+};
+
+static int jz4780_i2c_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+ unsigned int clk_freq = 0;
+ unsigned short tmp;
+ struct resource *r;
+ struct jz4780_i2c *i2c;
+
+ i2c = devm_kzalloc(&pdev->dev, sizeof(struct jz4780_i2c), GFP_KERNEL);
+ if (!i2c)
+ return -ENOMEM;
+
+ i2c->adap.owner = THIS_MODULE;
+ i2c->adap.algo = &jz4780_i2c_algorithm;
+ i2c->adap.algo_data = i2c;
+ i2c->adap.retries = 5;
+ i2c->adap.dev.parent = &pdev->dev;
+ i2c->adap.dev.of_node = pdev->dev.of_node;
+ sprintf(i2c->adap.name, "%s", pdev->name);
+
+ init_completion(&i2c->trans_waitq);
+ spin_lock_init(&i2c->lock);
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ i2c->iomem = devm_ioremap_resource(&pdev->dev, r);
+ if (IS_ERR(i2c->iomem))
+ return PTR_ERR(i2c->iomem);
+
+ platform_set_drvdata(pdev, i2c);
+
+ i2c->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(i2c->clk))
+ return PTR_ERR(i2c->clk);
+
+ clk_prepare_enable(i2c->clk);
+
+ if (of_property_read_u32(pdev->dev.of_node, "clock-frequency",
+ &clk_freq)) {
+ dev_err(&pdev->dev, "clock-frequency not specified in DT");
+ return clk_freq;
+ }
+
+ i2c->speed = clk_freq / 1000;
+ jz4780_i2c_set_speed(i2c);
+
+ dev_info(&pdev->dev, "Bus frequency is %d KHz\n", i2c->speed);
+
+ tmp = jz4780_i2c_readw(i2c, JZ4780_I2C_CTRL);
+ tmp &= ~JZ4780_I2C_CTRL_STPHLD;
+ jz4780_i2c_writew(i2c, JZ4780_I2C_CTRL, tmp);
+
+ jz4780_i2c_writew(i2c, JZ4780_I2C_INTM, 0x0);
+
+ i2c->cmd = 0;
+ memset(i2c->cmd_buf, 0, BUFSIZE);
+ memset(i2c->data_buf, 0, BUFSIZE);
+
+ i2c->irq = platform_get_irq(pdev, 0);
+ ret = devm_request_irq(&pdev->dev, i2c->irq, jz4780_i2c_irq, 0,
+ dev_name(&pdev->dev), i2c);
+ if (ret) {
+ ret = -ENODEV;
+ goto err;
+ }
+
+ ret = i2c_add_adapter(&i2c->adap);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Failed to add bus\n");
+ goto err;
+ }
+
+ return 0;
+
+err:
+ clk_disable_unprepare(i2c->clk);
+ return ret;
+}
+
+static int jz4780_i2c_remove(struct platform_device *pdev)
+{
+ struct jz4780_i2c *i2c = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(i2c->clk);
+ i2c_del_adapter(&i2c->adap);
+ return 0;
+}
+
+static struct platform_driver jz4780_i2c_driver = {
+ .probe = jz4780_i2c_probe,
+ .remove = jz4780_i2c_remove,
+ .driver = {
+ .name = "jz4780-i2c",
+ .of_match_table = of_match_ptr(jz4780_i2c_of_matches),
+ },
+};
+
+module_platform_driver(jz4780_i2c_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("ztyan<ztyan@ingenic.cn>");
+MODULE_DESCRIPTION("i2c driver for JZ4780 SoCs");
Code Review / kvmfornfv.git / blobdiff