summaryrefslogtreecommitdiffstats
path: root/drivers/i2c/busses/i2c-eg20t.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/i2c/busses/i2c-eg20t.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/i2c/busses/i2c-eg20t.c')
-rw-r--r--drivers/i2c/busses/i2c-eg20t.c907
1 files changed, 907 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c
new file mode 100644
index 000000000..4914bfbee
--- /dev/null
+++ b/drivers/i2c/busses/i2c-eg20t.c
@@ -0,0 +1,907 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2011 LAPIS Semiconductor Co., Ltd.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/delay.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_RESTART 0x0004
+#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
+LAPIS Semiconductor ML7213 IOH : 2ch
+LAPIS Semiconductor ML7831 IOH : 1ch
+*/
+#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 LAPIS Semiconductor */
+#define PCI_DEVICE_ID_ML7213_I2C 0x802D
+#define PCI_DEVICE_ID_ML7223_I2C 0x8010
+#define PCI_DEVICE_ID_ML7831_I2C 0x8817
+
+static const struct pci_device_id 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, },
+ { PCI_VDEVICE(ROHM, PCI_DEVICE_ID_ML7831_I2C), 1, },
+ {0,}
+};
+MODULE_DEVICE_TABLE(pci, pch_pcidev_id);
+
+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);
+}
+
+/**
+ * pch_i2c_wait_for_bus_idle() - check the status of bus.
+ * @adap: Pointer to struct i2c_algo_pch_data.
+ * @timeout: waiting time counter (ms).
+ */
+static s32 pch_i2c_wait_for_bus_idle(struct i2c_algo_pch_data *adap,
+ s32 timeout)
+{
+ void __iomem *p = adap->pch_base_address;
+ int schedule = 0;
+ unsigned long end = jiffies + msecs_to_jiffies(timeout);
+
+ while (ioread32(p + PCH_I2CSR) & I2CMBB_BIT) {
+ if (time_after(jiffies, end)) {
+ pch_dbg(adap, "I2CSR = %x\n", ioread32(p + PCH_I2CSR));
+ pch_err(adap, "%s: Timeout Error.return%d\n",
+ __func__, -ETIME);
+ pch_i2c_init(adap);
+
+ return -ETIME;
+ }
+
+ if (!schedule)
+ /* Retry after some usecs */
+ udelay(5);
+ else
+ /* Wait a bit more without consuming CPU */
+ usleep_range(20, 1000);
+
+ schedule = 1;
+ }
+
+ 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_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);
+}
+
+static int pch_i2c_wait_for_check_xfer(struct i2c_algo_pch_data *adap)
+{
+ long ret;
+ void __iomem *p = adap->pch_base_address;
+
+ ret = wait_event_timeout(pch_event,
+ (adap->pch_event_flag != 0), msecs_to_jiffies(1000));
+ if (!ret) {
+ pch_err(adap, "%s:wait-event timeout\n", __func__);
+ adap->pch_event_flag = 0;
+ pch_i2c_stop(adap);
+ pch_i2c_init(adap);
+ return -ETIMEDOUT;
+ }
+
+ if (adap->pch_event_flag & I2C_ERROR_MASK) {
+ pch_err(adap, "Lost Arbitration\n");
+ adap->pch_event_flag = 0;
+ pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMAL_BIT);
+ pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT);
+ pch_i2c_init(adap);
+ return -EAGAIN;
+ }
+
+ adap->pch_event_flag = 0;
+
+ if (ioread32(p + PCH_I2CSR) & PCH_GETACK) {
+ pch_dbg(adap, "Receive NACK for slave address setting\n");
+ return -ENXIO;
+ }
+
+ return 0;
+}
+
+/**
+ * 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.
+ * @msgs: Pointer to the i2c message structure.
+ * @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;
+ s32 rtn;
+ 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) & 0x06;
+ iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
+ if (first)
+ pch_i2c_start(adap);
+
+ rtn = pch_i2c_wait_for_check_xfer(adap);
+ if (rtn)
+ return rtn;
+
+ addr_8_lsb = (addr & I2C_ADDR_MSK);
+ iowrite32(addr_8_lsb, p + PCH_I2CDR);
+ } else {
+ /* set 7 bit slave address and R/W bit as 0 */
+ iowrite32(i2c_8bit_addr_from_msg(msgs), p + PCH_I2CDR);
+ if (first)
+ pch_i2c_start(adap);
+ }
+
+ rtn = pch_i2c_wait_for_check_xfer(adap);
+ if (rtn)
+ return rtn;
+
+ 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]);
+
+ rtn = pch_i2c_wait_for_check_xfer(adap);
+ if (rtn)
+ return rtn;
+
+ pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMCF_BIT);
+ pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT);
+ }
+
+ /* check if this is the last message */
+ if (last)
+ pch_i2c_stop(adap);
+ else
+ pch_i2c_repstart(adap);
+
+ 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_restart() - Generate I2C restart condition in normal mode.
+ * @adap: Pointer to struct i2c_algo_pch_data.
+ *
+ * Generate I2C restart condition in normal mode by setting I2CCTL.I2CRSTA.
+ */
+static void pch_i2c_restart(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_RESTART);
+}
+
+/**
+ * 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;
+ u32 addr_8_lsb;
+ void __iomem *p = adap->pch_base_address;
+ s32 rtn;
+
+ 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);
+ iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
+ if (first)
+ pch_i2c_start(adap);
+
+ rtn = pch_i2c_wait_for_check_xfer(adap);
+ if (rtn)
+ return rtn;
+
+ addr_8_lsb = (addr & I2C_ADDR_MSK);
+ iowrite32(addr_8_lsb, p + PCH_I2CDR);
+
+ pch_i2c_restart(adap);
+
+ rtn = pch_i2c_wait_for_check_xfer(adap);
+ if (rtn)
+ return rtn;
+
+ addr_2_msb |= I2C_RD;
+ iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
+ } else {
+ /* 7 address bits + R/W bit */
+ iowrite32(i2c_8bit_addr_from_msg(msgs), p + PCH_I2CDR);
+ }
+
+ /* check if it is the first message */
+ if (first)
+ pch_i2c_start(adap);
+
+ rtn = pch_i2c_wait_for_check_xfer(adap);
+ if (rtn)
+ return rtn;
+
+ 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++;
+
+ rtn = pch_i2c_wait_for_check_xfer(adap);
+ if (rtn)
+ return rtn;
+ } /* end for */
+
+ pch_i2c_sendnack(adap);
+
+ buf[read_index] = ioread32(p + PCH_I2CDR); /* Read final - 1 */
+
+ if (length != 1)
+ read_index++;
+
+ rtn = pch_i2c_wait_for_check_xfer(adap);
+ if (rtn)
+ return rtn;
+
+ if (last)
+ pch_i2c_stop(adap);
+ else
+ pch_i2c_repstart(adap);
+
+ buf[read_index++] = ioread32(p + PCH_I2CDR); /* Read Final */
+ count = read_index;
+ }
+
+ 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;
+ s32 ret;
+
+ struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
+
+ ret = mutex_lock_interruptible(&pch_mutex);
+ if (ret)
+ return ret;
+
+ 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;
+
+ for (i = 0; i < num && ret >= 0; i++) {
+ pmsg = &msgs[i];
+ pmsg->flags |= adap->pch_buff_mode_en;
+ status = pmsg->flags;
+ pch_dbg(adap,
+ "After invoking I2C_MODE_SEL :flag= 0x%x\n", status);
+
+ if ((status & (I2C_M_RD)) != false) {
+ ret = pch_i2c_readbytes(i2c_adap, pmsg, (i + 1 == num),
+ (i == 0));
+ } else {
+ 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 < 0) ? ret : num;
+}
+
+/**
+ * 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 const 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 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)
+ 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;
+ strscpy(pch_adap->name, KBUILD_MODNAME, sizeof(pch_adap->name));
+ 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.of_node = pdev->dev.of_node;
+ pch_adap->dev.parent = &pdev->dev;
+ }
+
+ 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_request_irq;
+ }
+
+ for (i = 0; i < adap_info->ch_num; i++) {
+ pch_adap = &adap_info->pch_data[i].pch_adapter;
+
+ pch_i2c_init(&adap_info->pch_data[i]);
+
+ pch_adap->nr = i;
+ ret = i2c_add_numbered_adapter(pch_adap);
+ if (ret) {
+ pch_pci_err(pdev, "i2c_add_adapter[ch:%d] FAILED\n", i);
+ goto err_add_adapter;
+ }
+ }
+
+ pci_set_drvdata(pdev, adap_info);
+ pch_pci_dbg(pdev, "returns %d.\n", ret);
+ return 0;
+
+err_add_adapter:
+ for (j = 0; j < i; j++)
+ i2c_del_adapter(&adap_info->pch_data[j].pch_adapter);
+ free_irq(pdev->irq, adap_info);
+err_request_irq:
+ 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 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 = NULL;
+
+ pci_release_regions(pdev);
+
+ pci_disable_device(pdev);
+ kfree(adap_info);
+}
+
+static int __maybe_unused pch_i2c_suspend(struct device *dev)
+{
+ int i;
+ struct pci_dev *pdev = to_pci_dev(dev);
+ 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));
+
+ return 0;
+}
+
+static int __maybe_unused pch_i2c_resume(struct device *dev)
+{
+ int i;
+ struct adapter_info *adap_info = dev_get_drvdata(dev);
+
+ 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;
+}
+
+static SIMPLE_DEV_PM_OPS(pch_i2c_pm_ops, pch_i2c_suspend, pch_i2c_resume);
+
+static struct pci_driver pch_pcidriver = {
+ .name = KBUILD_MODNAME,
+ .id_table = pch_pcidev_id,
+ .probe = pch_i2c_probe,
+ .remove = pch_i2c_remove,
+ .driver.pm = &pch_i2c_pm_ops,
+};
+
+module_pci_driver(pch_pcidriver);
+
+MODULE_DESCRIPTION("Intel EG20T PCH/LAPIS Semico ML7213/ML7223/ML7831 IOH I2C");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Tomoya MORINAGA. <tomoya.rohm@gmail.com>");
+module_param(pch_i2c_speed, int, (S_IRUSR | S_IWUSR));
+module_param(pch_clk, int, (S_IRUSR | S_IWUSR));