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linux_dsm_epyc7002/drivers/i2c/busses/i2c-eg20t.c
Tomoya MORINAGA efbe0f27cc i2c-eg20t: Support new device ML7223 IOH 
Support new device OKI SEMICONDUCTOR ML7223 IOH(Input/Output Hub).
The ML7223 IOH is for MP(Media Phone) use.
The ML7223 is companion chip for Intel Atom E6xx series.
The ML7223 is completely compatible for Intel EG20T PCH.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
2011-05-11 06:50:02 +01:00

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/*
* Copyright (C) 2010 OKI SEMICONDUCTOR CO., LTD.
*
* 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; version 2 of the License.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/i2c.h>
#include <linux/fs.h>
#include <linux/io.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/jiffies.h>
#include <linux/pci.h>
#include <linux/mutex.h>
#include <linux/ktime.h>
#include <linux/slab.h>
#define PCH_EVENT_SET 0 /* I2C Interrupt Event Set Status */
#define PCH_EVENT_NONE 1 /* I2C Interrupt Event Clear Status */
#define PCH_MAX_CLK 100000 /* Maximum Clock speed in MHz */
#define PCH_BUFFER_MODE_ENABLE 0x0002 /* flag for Buffer mode enable */
#define PCH_EEPROM_SW_RST_MODE_ENABLE 0x0008 /* EEPROM SW RST enable flag */
#define PCH_I2CSADR 0x00 /* I2C slave address register */
#define PCH_I2CCTL 0x04 /* I2C control register */
#define PCH_I2CSR 0x08 /* I2C status register */
#define PCH_I2CDR 0x0C /* I2C data register */
#define PCH_I2CMON 0x10 /* I2C bus monitor register */
#define PCH_I2CBC 0x14 /* I2C bus transfer rate setup counter */
#define PCH_I2CMOD 0x18 /* I2C mode register */
#define PCH_I2CBUFSLV 0x1C /* I2C buffer mode slave address register */
#define PCH_I2CBUFSUB 0x20 /* I2C buffer mode subaddress register */
#define PCH_I2CBUFFOR 0x24 /* I2C buffer mode format register */
#define PCH_I2CBUFCTL 0x28 /* I2C buffer mode control register */
#define PCH_I2CBUFMSK 0x2C /* I2C buffer mode interrupt mask register */
#define PCH_I2CBUFSTA 0x30 /* I2C buffer mode status register */
#define PCH_I2CBUFLEV 0x34 /* I2C buffer mode level register */
#define PCH_I2CESRFOR 0x38 /* EEPROM software reset mode format register */
#define PCH_I2CESRCTL 0x3C /* EEPROM software reset mode ctrl register */
#define PCH_I2CESRMSK 0x40 /* EEPROM software reset mode */
#define PCH_I2CESRSTA 0x44 /* EEPROM software reset mode status register */
#define PCH_I2CTMR 0x48 /* I2C timer register */
#define PCH_I2CSRST 0xFC /* I2C reset register */
#define PCH_I2CNF 0xF8 /* I2C noise filter register */
#define BUS_IDLE_TIMEOUT 20
#define PCH_I2CCTL_I2CMEN 0x0080
#define TEN_BIT_ADDR_DEFAULT 0xF000
#define TEN_BIT_ADDR_MASK 0xF0
#define PCH_START 0x0020
#define PCH_ESR_START 0x0001
#define PCH_BUFF_START 0x1
#define PCH_REPSTART 0x0004
#define PCH_ACK 0x0008
#define PCH_GETACK 0x0001
#define CLR_REG 0x0
#define I2C_RD 0x1
#define I2CMCF_BIT 0x0080
#define I2CMIF_BIT 0x0002
#define I2CMAL_BIT 0x0010
#define I2CBMFI_BIT 0x0001
#define I2CBMAL_BIT 0x0002
#define I2CBMNA_BIT 0x0004
#define I2CBMTO_BIT 0x0008
#define I2CBMIS_BIT 0x0010
#define I2CESRFI_BIT 0X0001
#define I2CESRTO_BIT 0x0002
#define I2CESRFIIE_BIT 0x1
#define I2CESRTOIE_BIT 0x2
#define I2CBMDZ_BIT 0x0040
#define I2CBMAG_BIT 0x0020
#define I2CMBB_BIT 0x0020
#define BUFFER_MODE_MASK (I2CBMFI_BIT | I2CBMAL_BIT | I2CBMNA_BIT | \
I2CBMTO_BIT | I2CBMIS_BIT)
#define I2C_ADDR_MSK 0xFF
#define I2C_MSB_2B_MSK 0x300
#define FAST_MODE_CLK 400
#define FAST_MODE_EN 0x0001
#define SUB_ADDR_LEN_MAX 4
#define BUF_LEN_MAX 32
#define PCH_BUFFER_MODE 0x1
#define EEPROM_SW_RST_MODE 0x0002
#define NORMAL_INTR_ENBL 0x0300
#define EEPROM_RST_INTR_ENBL (I2CESRFIIE_BIT | I2CESRTOIE_BIT)
#define EEPROM_RST_INTR_DISBL 0x0
#define BUFFER_MODE_INTR_ENBL 0x001F
#define BUFFER_MODE_INTR_DISBL 0x0
#define NORMAL_MODE 0x0
#define BUFFER_MODE 0x1
#define EEPROM_SR_MODE 0x2
#define I2C_TX_MODE 0x0010
#define PCH_BUF_TX 0xFFF7
#define PCH_BUF_RD 0x0008
#define I2C_ERROR_MASK (I2CESRTO_EVENT | I2CBMIS_EVENT | I2CBMTO_EVENT | \
I2CBMNA_EVENT | I2CBMAL_EVENT | I2CMAL_EVENT)
#define I2CMAL_EVENT 0x0001
#define I2CMCF_EVENT 0x0002
#define I2CBMFI_EVENT 0x0004
#define I2CBMAL_EVENT 0x0008
#define I2CBMNA_EVENT 0x0010
#define I2CBMTO_EVENT 0x0020
#define I2CBMIS_EVENT 0x0040
#define I2CESRFI_EVENT 0x0080
#define I2CESRTO_EVENT 0x0100
#define PCI_DEVICE_ID_PCH_I2C 0x8817
#define pch_dbg(adap, fmt, arg...) \
dev_dbg(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg)
#define pch_err(adap, fmt, arg...) \
dev_err(adap->pch_adapter.dev.parent, "%s :" fmt, __func__, ##arg)
#define pch_pci_err(pdev, fmt, arg...) \
dev_err(&pdev->dev, "%s :" fmt, __func__, ##arg)
#define pch_pci_dbg(pdev, fmt, arg...) \
dev_dbg(&pdev->dev, "%s :" fmt, __func__, ##arg)
/*
Set the number of I2C instance max
Intel EG20T PCH : 1ch
OKI SEMICONDUCTOR ML7213 IOH : 2ch
*/
#define PCH_I2C_MAX_DEV 2
/**
* struct i2c_algo_pch_data - for I2C driver functionalities
* @pch_adapter: stores the reference to i2c_adapter structure
* @p_adapter_info: stores the reference to adapter_info structure
* @pch_base_address: specifies the remapped base address
* @pch_buff_mode_en: specifies if buffer mode is enabled
* @pch_event_flag: specifies occurrence of interrupt events
* @pch_i2c_xfer_in_progress: specifies whether the transfer is completed
*/
struct i2c_algo_pch_data {
struct i2c_adapter pch_adapter;
struct adapter_info *p_adapter_info;
void __iomem *pch_base_address;
int pch_buff_mode_en;
u32 pch_event_flag;
bool pch_i2c_xfer_in_progress;
};
/**
* struct adapter_info - This structure holds the adapter information for the
PCH i2c controller
* @pch_data: stores a list of i2c_algo_pch_data
* @pch_i2c_suspended: specifies whether the system is suspended or not
* perhaps with more lines and words.
* @ch_num: specifies the number of i2c instance
*
* pch_data has as many elements as maximum I2C channels
*/
struct adapter_info {
struct i2c_algo_pch_data pch_data[PCH_I2C_MAX_DEV];
bool pch_i2c_suspended;
int ch_num;
};
static int pch_i2c_speed = 100; /* I2C bus speed in Kbps */
static int pch_clk = 50000; /* specifies I2C clock speed in KHz */
static wait_queue_head_t pch_event;
static DEFINE_MUTEX(pch_mutex);
/* Definition for ML7213 by OKI SEMICONDUCTOR */
#define PCI_VENDOR_ID_ROHM 0x10DB
#define PCI_DEVICE_ID_ML7213_I2C 0x802D
#define PCI_DEVICE_ID_ML7223_I2C 0x8010
static struct pci_device_id __devinitdata pch_pcidev_id[] = {
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_PCH_I2C), 1, },
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7213_I2C), 2, },
{ PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7223_I2C), 1, },
{0,}
};
static irqreturn_t pch_i2c_handler(int irq, void *pData);
static inline void pch_setbit(void __iomem *addr, u32 offset, u32 bitmask)
{
u32 val;
val = ioread32(addr + offset);
val |= bitmask;
iowrite32(val, addr + offset);
}
static inline void pch_clrbit(void __iomem *addr, u32 offset, u32 bitmask)
{
u32 val;
val = ioread32(addr + offset);
val &= (~bitmask);
iowrite32(val, addr + offset);
}
/**
* pch_i2c_init() - hardware initialization of I2C module
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static void pch_i2c_init(struct i2c_algo_pch_data *adap)
{
void __iomem *p = adap->pch_base_address;
u32 pch_i2cbc;
u32 pch_i2ctmr;
u32 reg_value;
/* reset I2C controller */
iowrite32(0x01, p + PCH_I2CSRST);
msleep(20);
iowrite32(0x0, p + PCH_I2CSRST);
/* Initialize I2C registers */
iowrite32(0x21, p + PCH_I2CNF);
pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_I2CCTL_I2CMEN);
if (pch_i2c_speed != 400)
pch_i2c_speed = 100;
reg_value = PCH_I2CCTL_I2CMEN;
if (pch_i2c_speed == FAST_MODE_CLK) {
reg_value |= FAST_MODE_EN;
pch_dbg(adap, "Fast mode enabled\n");
}
if (pch_clk > PCH_MAX_CLK)
pch_clk = 62500;
pch_i2cbc = (pch_clk + (pch_i2c_speed * 4)) / pch_i2c_speed * 8;
/* Set transfer speed in I2CBC */
iowrite32(pch_i2cbc, p + PCH_I2CBC);
pch_i2ctmr = (pch_clk) / 8;
iowrite32(pch_i2ctmr, p + PCH_I2CTMR);
reg_value |= NORMAL_INTR_ENBL; /* Enable interrupts in normal mode */
iowrite32(reg_value, p + PCH_I2CCTL);
pch_dbg(adap,
"I2CCTL=%x pch_i2cbc=%x pch_i2ctmr=%x Enable interrupts\n",
ioread32(p + PCH_I2CCTL), pch_i2cbc, pch_i2ctmr);
init_waitqueue_head(&pch_event);
}
static inline bool ktime_lt(const ktime_t cmp1, const ktime_t cmp2)
{
return cmp1.tv64 < cmp2.tv64;
}
/**
* pch_i2c_wait_for_bus_idle() - check the status of bus.
* @adap: Pointer to struct i2c_algo_pch_data.
* @timeout: waiting time counter (us).
*/
static s32 pch_i2c_wait_for_bus_idle(struct i2c_algo_pch_data *adap,
s32 timeout)
{
void __iomem *p = adap->pch_base_address;
/* MAX timeout value is timeout*1000*1000nsec */
ktime_t ns_val = ktime_add_ns(ktime_get(), timeout*1000*1000);
do {
if ((ioread32(p + PCH_I2CSR) & I2CMBB_BIT) == 0)
break;
msleep(20);
} while (ktime_lt(ktime_get(), ns_val));
pch_dbg(adap, "I2CSR = %x\n", ioread32(p + PCH_I2CSR));
if (timeout == 0) {
pch_err(adap, "%s: Timeout Error.return%d\n", __func__, -ETIME);
return -ETIME;
}
return 0;
}
/**
* pch_i2c_start() - Generate I2C start condition in normal mode.
* @adap: Pointer to struct i2c_algo_pch_data.
*
* Generate I2C start condition in normal mode by setting I2CCTL.I2CMSTA to 1.
*/
static void pch_i2c_start(struct i2c_algo_pch_data *adap)
{
void __iomem *p = adap->pch_base_address;
pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_START);
}
/**
* pch_i2c_wait_for_xfer_complete() - initiates a wait for the tx complete event
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static s32 pch_i2c_wait_for_xfer_complete(struct i2c_algo_pch_data *adap)
{
s32 ret;
ret = wait_event_timeout(pch_event,
(adap->pch_event_flag != 0), msecs_to_jiffies(50));
if (ret < 0) {
pch_err(adap, "timeout: %x\n", adap->pch_event_flag);
return ret;
}
if (ret == 0) {
pch_err(adap, "timeout: %x\n", adap->pch_event_flag);
return -ETIMEDOUT;
}
if (adap->pch_event_flag & I2C_ERROR_MASK) {
pch_err(adap, "error bits set: %x\n", adap->pch_event_flag);
return -EIO;
}
adap->pch_event_flag = 0;
return 0;
}
/**
* pch_i2c_getack() - to confirm ACK/NACK
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static s32 pch_i2c_getack(struct i2c_algo_pch_data *adap)
{
u32 reg_val;
void __iomem *p = adap->pch_base_address;
reg_val = ioread32(p + PCH_I2CSR) & PCH_GETACK;
if (reg_val != 0) {
pch_err(adap, "return%d\n", -EPROTO);
return -EPROTO;
}
return 0;
}
/**
* pch_i2c_stop() - generate stop condition in normal mode.
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static void pch_i2c_stop(struct i2c_algo_pch_data *adap)
{
void __iomem *p = adap->pch_base_address;
pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
/* clear the start bit */
pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_START);
}
/**
* pch_i2c_repstart() - generate repeated start condition in normal mode
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static void pch_i2c_repstart(struct i2c_algo_pch_data *adap)
{
void __iomem *p = adap->pch_base_address;
pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_REPSTART);
}
/**
* pch_i2c_writebytes() - write data to I2C bus in normal mode
* @i2c_adap: Pointer to the struct i2c_adapter.
* @last: specifies whether last message or not.
* In the case of compound mode it will be 1 for last message,
* otherwise 0.
* @first: specifies whether first message or not.
* 1 for first message otherwise 0.
*/
static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap,
struct i2c_msg *msgs, u32 last, u32 first)
{
struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
u8 *buf;
u32 length;
u32 addr;
u32 addr_2_msb;
u32 addr_8_lsb;
s32 wrcount;
void __iomem *p = adap->pch_base_address;
length = msgs->len;
buf = msgs->buf;
addr = msgs->addr;
/* enable master tx */
pch_setbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE);
pch_dbg(adap, "I2CCTL = %x msgs->len = %d\n", ioread32(p + PCH_I2CCTL),
length);
if (first) {
if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME)
return -ETIME;
}
if (msgs->flags & I2C_M_TEN) {
addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7);
iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
if (first)
pch_i2c_start(adap);
if (pch_i2c_wait_for_xfer_complete(adap) == 0 &&
pch_i2c_getack(adap) == 0) {
addr_8_lsb = (addr & I2C_ADDR_MSK);
iowrite32(addr_8_lsb, p + PCH_I2CDR);
} else {
pch_i2c_stop(adap);
return -ETIME;
}
} else {
/* set 7 bit slave address and R/W bit as 0 */
iowrite32(addr << 1, p + PCH_I2CDR);
if (first)
pch_i2c_start(adap);
}
if ((pch_i2c_wait_for_xfer_complete(adap) == 0) &&
(pch_i2c_getack(adap) == 0)) {
for (wrcount = 0; wrcount < length; ++wrcount) {
/* write buffer value to I2C data register */
iowrite32(buf[wrcount], p + PCH_I2CDR);
pch_dbg(adap, "writing %x to Data register\n",
buf[wrcount]);
if (pch_i2c_wait_for_xfer_complete(adap) != 0)
return -ETIME;
if (pch_i2c_getack(adap))
return -EIO;
}
/* check if this is the last message */
if (last)
pch_i2c_stop(adap);
else
pch_i2c_repstart(adap);
} else {
pch_i2c_stop(adap);
return -EIO;
}
pch_dbg(adap, "return=%d\n", wrcount);
return wrcount;
}
/**
* pch_i2c_sendack() - send ACK
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static void pch_i2c_sendack(struct i2c_algo_pch_data *adap)
{
void __iomem *p = adap->pch_base_address;
pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
pch_clrbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK);
}
/**
* pch_i2c_sendnack() - send NACK
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static void pch_i2c_sendnack(struct i2c_algo_pch_data *adap)
{
void __iomem *p = adap->pch_base_address;
pch_dbg(adap, "I2CCTL = %x\n", ioread32(p + PCH_I2CCTL));
pch_setbit(adap->pch_base_address, PCH_I2CCTL, PCH_ACK);
}
/**
* pch_i2c_readbytes() - read data from I2C bus in normal mode.
* @i2c_adap: Pointer to the struct i2c_adapter.
* @msgs: Pointer to i2c_msg structure.
* @last: specifies whether last message or not.
* @first: specifies whether first message or not.
*/
static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs,
u32 last, u32 first)
{
struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
u8 *buf;
u32 count;
u32 length;
u32 addr;
u32 addr_2_msb;
void __iomem *p = adap->pch_base_address;
length = msgs->len;
buf = msgs->buf;
addr = msgs->addr;
/* enable master reception */
pch_clrbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE);
if (first) {
if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME)
return -ETIME;
}
if (msgs->flags & I2C_M_TEN) {
addr_2_msb = (((addr & I2C_MSB_2B_MSK) >> 7) | (I2C_RD));
iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
} else {
/* 7 address bits + R/W bit */
addr = (((addr) << 1) | (I2C_RD));
iowrite32(addr, p + PCH_I2CDR);
}
/* check if it is the first message */
if (first)
pch_i2c_start(adap);
if ((pch_i2c_wait_for_xfer_complete(adap) == 0) &&
(pch_i2c_getack(adap) == 0)) {
pch_dbg(adap, "return %d\n", 0);
if (length == 0) {
pch_i2c_stop(adap);
ioread32(p + PCH_I2CDR); /* Dummy read needs */
count = length;
} else {
int read_index;
int loop;
pch_i2c_sendack(adap);
/* Dummy read */
for (loop = 1, read_index = 0; loop < length; loop++) {
buf[read_index] = ioread32(p + PCH_I2CDR);
if (loop != 1)
read_index++;
if (pch_i2c_wait_for_xfer_complete(adap) != 0) {
pch_i2c_stop(adap);
return -ETIME;
}
} /* end for */
pch_i2c_sendnack(adap);
buf[read_index] = ioread32(p + PCH_I2CDR);
if (length != 1)
read_index++;
if (pch_i2c_wait_for_xfer_complete(adap) == 0) {
if (last)
pch_i2c_stop(adap);
else
pch_i2c_repstart(adap);
buf[read_index++] = ioread32(p + PCH_I2CDR);
count = read_index;
} else {
count = -ETIME;
}
}
} else {
count = -ETIME;
pch_i2c_stop(adap);
}
return count;
}
/**
* pch_i2c_cb() - Interrupt handler Call back function
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static void pch_i2c_cb(struct i2c_algo_pch_data *adap)
{
u32 sts;
void __iomem *p = adap->pch_base_address;
sts = ioread32(p + PCH_I2CSR);
sts &= (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT);
if (sts & I2CMAL_BIT)
adap->pch_event_flag |= I2CMAL_EVENT;
if (sts & I2CMCF_BIT)
adap->pch_event_flag |= I2CMCF_EVENT;
/* clear the applicable bits */
pch_clrbit(adap->pch_base_address, PCH_I2CSR, sts);
pch_dbg(adap, "PCH_I2CSR = %x\n", ioread32(p + PCH_I2CSR));
wake_up(&pch_event);
}
/**
* pch_i2c_handler() - interrupt handler for the PCH I2C controller
* @irq: irq number.
* @pData: cookie passed back to the handler function.
*/
static irqreturn_t pch_i2c_handler(int irq, void *pData)
{
u32 reg_val;
int flag;
int i;
struct adapter_info *adap_info = pData;
void __iomem *p;
u32 mode;
for (i = 0, flag = 0; i < adap_info->ch_num; i++) {
p = adap_info->pch_data[i].pch_base_address;
mode = ioread32(p + PCH_I2CMOD);
mode &= BUFFER_MODE | EEPROM_SR_MODE;
if (mode != NORMAL_MODE) {
pch_err(adap_info->pch_data,
"I2C-%d mode(%d) is not supported\n", mode, i);
continue;
}
reg_val = ioread32(p + PCH_I2CSR);
if (reg_val & (I2CMAL_BIT | I2CMCF_BIT | I2CMIF_BIT)) {
pch_i2c_cb(&adap_info->pch_data[i]);
flag = 1;
}
}
return flag ? IRQ_HANDLED : IRQ_NONE;
}
/**
* pch_i2c_xfer() - Reading adnd writing data through I2C bus
* @i2c_adap: Pointer to the struct i2c_adapter.
* @msgs: Pointer to i2c_msg structure.
* @num: number of messages.
*/
static s32 pch_i2c_xfer(struct i2c_adapter *i2c_adap,
struct i2c_msg *msgs, s32 num)
{
struct i2c_msg *pmsg;
u32 i = 0;
u32 status;
u32 msglen;
u32 subaddrlen;
s32 ret;
struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
ret = mutex_lock_interruptible(&pch_mutex);
if (ret)
return -ERESTARTSYS;
if (adap->p_adapter_info->pch_i2c_suspended) {
mutex_unlock(&pch_mutex);
return -EBUSY;
}
pch_dbg(adap, "adap->p_adapter_info->pch_i2c_suspended is %d\n",
adap->p_adapter_info->pch_i2c_suspended);
/* transfer not completed */
adap->pch_i2c_xfer_in_progress = true;
pmsg = &msgs[0];
pmsg->flags |= adap->pch_buff_mode_en;
status = pmsg->flags;
pch_dbg(adap,
"After invoking I2C_MODE_SEL :flag= 0x%x\n", status);
/* calculate sub address length and message length */
/* these are applicable only for buffer mode */
subaddrlen = pmsg->buf[0];
/* calculate actual message length excluding
* the sub address fields */
msglen = (pmsg->len) - (subaddrlen + 1);
if (status & (I2C_M_RD)) {
pch_dbg(adap, "invoking pch_i2c_readbytes\n");
ret = pch_i2c_readbytes(i2c_adap, pmsg, (i + 1 == num),
(i == 0));
} else {
pch_dbg(adap, "invoking pch_i2c_writebytes\n");
ret = pch_i2c_writebytes(i2c_adap, pmsg, (i + 1 == num),
(i == 0));
}
adap->pch_i2c_xfer_in_progress = false; /* transfer completed */
mutex_unlock(&pch_mutex);
return ret;
}
/**
* pch_i2c_func() - return the functionality of the I2C driver
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static u32 pch_i2c_func(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR;
}
static struct i2c_algorithm pch_algorithm = {
.master_xfer = pch_i2c_xfer,
.functionality = pch_i2c_func
};
/**
* pch_i2c_disbl_int() - Disable PCH I2C interrupts
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static void pch_i2c_disbl_int(struct i2c_algo_pch_data *adap)
{
void __iomem *p = adap->pch_base_address;
pch_clrbit(adap->pch_base_address, PCH_I2CCTL, NORMAL_INTR_ENBL);
iowrite32(EEPROM_RST_INTR_DISBL, p + PCH_I2CESRMSK);
iowrite32(BUFFER_MODE_INTR_DISBL, p + PCH_I2CBUFMSK);
}
static int __devinit pch_i2c_probe(struct pci_dev *pdev,
const struct pci_device_id *id)
{
void __iomem *base_addr;
int ret;
int i, j;
struct adapter_info *adap_info;
struct i2c_adapter *pch_adap;
pch_pci_dbg(pdev, "Entered.\n");
adap_info = kzalloc((sizeof(struct adapter_info)), GFP_KERNEL);
if (adap_info == NULL) {
pch_pci_err(pdev, "Memory allocation FAILED\n");
return -ENOMEM;
}
ret = pci_enable_device(pdev);
if (ret) {
pch_pci_err(pdev, "pci_enable_device FAILED\n");
goto err_pci_enable;
}
ret = pci_request_regions(pdev, KBUILD_MODNAME);
if (ret) {
pch_pci_err(pdev, "pci_request_regions FAILED\n");
goto err_pci_req;
}
base_addr = pci_iomap(pdev, 1, 0);
if (base_addr == NULL) {
pch_pci_err(pdev, "pci_iomap FAILED\n");
ret = -ENOMEM;
goto err_pci_iomap;
}
/* Set the number of I2C channel instance */
adap_info->ch_num = id->driver_data;
for (i = 0; i < adap_info->ch_num; i++) {
pch_adap = &adap_info->pch_data[i].pch_adapter;
adap_info->pch_i2c_suspended = false;
adap_info->pch_data[i].p_adapter_info = adap_info;
pch_adap->owner = THIS_MODULE;
pch_adap->class = I2C_CLASS_HWMON;
strcpy(pch_adap->name, KBUILD_MODNAME);
pch_adap->algo = &pch_algorithm;
pch_adap->algo_data = &adap_info->pch_data[i];
/* base_addr + offset; */
adap_info->pch_data[i].pch_base_address = base_addr + 0x100 * i;
pch_adap->dev.parent = &pdev->dev;
ret = i2c_add_adapter(pch_adap);
if (ret) {
pch_pci_err(pdev, "i2c_add_adapter[ch:%d] FAILED\n", i);
goto err_i2c_add_adapter;
}
pch_i2c_init(&adap_info->pch_data[i]);
}
ret = request_irq(pdev->irq, pch_i2c_handler, IRQF_SHARED,
KBUILD_MODNAME, adap_info);
if (ret) {
pch_pci_err(pdev, "request_irq FAILED\n");
goto err_i2c_add_adapter;
}
pci_set_drvdata(pdev, adap_info);
pch_pci_dbg(pdev, "returns %d.\n", ret);
return 0;
err_i2c_add_adapter:
for (j = 0; j < i; j++)
i2c_del_adapter(&adap_info->pch_data[j].pch_adapter);
pci_iounmap(pdev, base_addr);
err_pci_iomap:
pci_release_regions(pdev);
err_pci_req:
pci_disable_device(pdev);
err_pci_enable:
kfree(adap_info);
return ret;
}
static void __devexit pch_i2c_remove(struct pci_dev *pdev)
{
int i;
struct adapter_info *adap_info = pci_get_drvdata(pdev);
free_irq(pdev->irq, adap_info);
for (i = 0; i < adap_info->ch_num; i++) {
pch_i2c_disbl_int(&adap_info->pch_data[i]);
i2c_del_adapter(&adap_info->pch_data[i].pch_adapter);
}
if (adap_info->pch_data[0].pch_base_address)
pci_iounmap(pdev, adap_info->pch_data[0].pch_base_address);
for (i = 0; i < adap_info->ch_num; i++)
adap_info->pch_data[i].pch_base_address = 0;
pci_set_drvdata(pdev, NULL);
pci_release_regions(pdev);
pci_disable_device(pdev);
kfree(adap_info);
}
#ifdef CONFIG_PM
static int pch_i2c_suspend(struct pci_dev *pdev, pm_message_t state)
{
int ret;
int i;
struct adapter_info *adap_info = pci_get_drvdata(pdev);
void __iomem *p = adap_info->pch_data[0].pch_base_address;
adap_info->pch_i2c_suspended = true;
for (i = 0; i < adap_info->ch_num; i++) {
while ((adap_info->pch_data[i].pch_i2c_xfer_in_progress)) {
/* Wait until all channel transfers are completed */
msleep(20);
}
}
/* Disable the i2c interrupts */
for (i = 0; i < adap_info->ch_num; i++)
pch_i2c_disbl_int(&adap_info->pch_data[i]);
pch_pci_dbg(pdev, "I2CSR = %x I2CBUFSTA = %x I2CESRSTA = %x "
"invoked function pch_i2c_disbl_int successfully\n",
ioread32(p + PCH_I2CSR), ioread32(p + PCH_I2CBUFSTA),
ioread32(p + PCH_I2CESRSTA));
ret = pci_save_state(pdev);
if (ret) {
pch_pci_err(pdev, "pci_save_state\n");
return ret;
}
pci_enable_wake(pdev, PCI_D3hot, 0);
pci_disable_device(pdev);
pci_set_power_state(pdev, pci_choose_state(pdev, state));
return 0;
}
static int pch_i2c_resume(struct pci_dev *pdev)
{
int i;
struct adapter_info *adap_info = pci_get_drvdata(pdev);
pci_set_power_state(pdev, PCI_D0);
pci_restore_state(pdev);
if (pci_enable_device(pdev) < 0) {
pch_pci_err(pdev, "pch_i2c_resume:pci_enable_device FAILED\n");
return -EIO;
}
pci_enable_wake(pdev, PCI_D3hot, 0);
for (i = 0; i < adap_info->ch_num; i++)
pch_i2c_init(&adap_info->pch_data[i]);
adap_info->pch_i2c_suspended = false;
return 0;
}
#else
#define pch_i2c_suspend NULL
#define pch_i2c_resume NULL
#endif
static struct pci_driver pch_pcidriver = {
.name = KBUILD_MODNAME,
.id_table = pch_pcidev_id,
.probe = pch_i2c_probe,
.remove = __devexit_p(pch_i2c_remove),
.suspend = pch_i2c_suspend,
.resume = pch_i2c_resume
};
static int __init pch_pci_init(void)
{
return pci_register_driver(&pch_pcidriver);
}
module_init(pch_pci_init);
static void __exit pch_pci_exit(void)
{
pci_unregister_driver(&pch_pcidriver);
}
module_exit(pch_pci_exit);
MODULE_DESCRIPTION("Intel EG20T PCH/OKI SEMICONDUCTOR ML7213 IOH I2C Driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Tomoya MORINAGA. <tomoya-linux@dsn.okisemi.com>");
module_param(pch_i2c_speed, int, (S_IRUSR | S_IWUSR));
module_param(pch_clk, int, (S_IRUSR | S_IWUSR));
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