diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-intel-mid.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-intel-mid.c | 1135 |
1 files changed, 1135 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-intel-mid.c b/drivers/i2c/busses/i2c-intel-mid.c new file mode 100644 index 00000000..e828ac85 --- /dev/null +++ b/drivers/i2c/busses/i2c-intel-mid.c @@ -0,0 +1,1135 @@ +/* + * Support for Moorestown/Medfield I2C chip + * + * Copyright (c) 2009 Intel Corporation. + * Copyright (c) 2009 Synopsys. Inc. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, version + * 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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., 51 + * Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/err.h> +#include <linux/slab.h> +#include <linux/stat.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/pci.h> +#include <linux/interrupt.h> +#include <linux/pm_runtime.h> +#include <linux/io.h> + +#define DRIVER_NAME "i2c-intel-mid" +#define VERSION "Version 0.5ac2" +#define PLATFORM "Moorestown/Medfield" + +/* Tables use: 0 Moorestown, 1 Medfield */ +#define NUM_PLATFORMS 2 +enum platform_enum { + MOORESTOWN = 0, + MEDFIELD = 1, +}; + +enum mid_i2c_status { + STATUS_IDLE = 0, + STATUS_READ_START, + STATUS_READ_IN_PROGRESS, + STATUS_READ_SUCCESS, + STATUS_WRITE_START, + STATUS_WRITE_SUCCESS, + STATUS_XFER_ABORT, + STATUS_STANDBY +}; + +/** + * struct intel_mid_i2c_private - per device I²C context + * @adap: core i2c layer adapter information + * @dev: device reference for power management + * @base: register base + * @speed: speed mode for this port + * @complete: completion object for transaction wait + * @abort: reason for last abort + * @rx_buf: pointer into working receive buffer + * @rx_buf_len: receive buffer length + * @status: adapter state machine + * @msg: the message we are currently processing + * @platform: the MID device type we are part of + * @lock: transaction serialization + * + * We allocate one of these per device we discover, it holds the core + * i2c layer objects and the data we need to track privately. + */ +struct intel_mid_i2c_private { + struct i2c_adapter adap; + struct device *dev; + void __iomem *base; + int speed; + struct completion complete; + int abort; + u8 *rx_buf; + int rx_buf_len; + enum mid_i2c_status status; + struct i2c_msg *msg; + enum platform_enum platform; + struct mutex lock; +}; + +#define NUM_SPEEDS 3 + +#define ACTIVE 0 +#define STANDBY 1 + + +/* Control register */ +#define IC_CON 0x00 +#define SLV_DIS (1 << 6) /* Disable slave mode */ +#define RESTART (1 << 5) /* Send a Restart condition */ +#define ADDR_10BIT (1 << 4) /* 10-bit addressing */ +#define STANDARD_MODE (1 << 1) /* standard mode */ +#define FAST_MODE (2 << 1) /* fast mode */ +#define HIGH_MODE (3 << 1) /* high speed mode */ +#define MASTER_EN (1 << 0) /* Master mode */ + +/* Target address register */ +#define IC_TAR 0x04 +#define IC_TAR_10BIT_ADDR (1 << 12) /* 10-bit addressing */ +#define IC_TAR_SPECIAL (1 << 11) /* Perform special I2C cmd */ +#define IC_TAR_GC_OR_START (1 << 10) /* 0: Gerneral Call Address */ + /* 1: START BYTE */ +/* Slave Address Register */ +#define IC_SAR 0x08 /* Not used in Master mode */ + +/* High Speed Master Mode Code Address Register */ +#define IC_HS_MADDR 0x0c + +/* Rx/Tx Data Buffer and Command Register */ +#define IC_DATA_CMD 0x10 +#define IC_RD (1 << 8) /* 1: Read 0: Write */ + +/* Standard Speed Clock SCL High Count Register */ +#define IC_SS_SCL_HCNT 0x14 + +/* Standard Speed Clock SCL Low Count Register */ +#define IC_SS_SCL_LCNT 0x18 + +/* Fast Speed Clock SCL High Count Register */ +#define IC_FS_SCL_HCNT 0x1c + +/* Fast Spedd Clock SCL Low Count Register */ +#define IC_FS_SCL_LCNT 0x20 + +/* High Speed Clock SCL High Count Register */ +#define IC_HS_SCL_HCNT 0x24 + +/* High Speed Clock SCL Low Count Register */ +#define IC_HS_SCL_LCNT 0x28 + +/* Interrupt Status Register */ +#define IC_INTR_STAT 0x2c /* Read only */ +#define R_GEN_CALL (1 << 11) +#define R_START_DET (1 << 10) +#define R_STOP_DET (1 << 9) +#define R_ACTIVITY (1 << 8) +#define R_RX_DONE (1 << 7) +#define R_TX_ABRT (1 << 6) +#define R_RD_REQ (1 << 5) +#define R_TX_EMPTY (1 << 4) +#define R_TX_OVER (1 << 3) +#define R_RX_FULL (1 << 2) +#define R_RX_OVER (1 << 1) +#define R_RX_UNDER (1 << 0) + +/* Interrupt Mask Register */ +#define IC_INTR_MASK 0x30 /* Read and Write */ +#define M_GEN_CALL (1 << 11) +#define M_START_DET (1 << 10) +#define M_STOP_DET (1 << 9) +#define M_ACTIVITY (1 << 8) +#define M_RX_DONE (1 << 7) +#define M_TX_ABRT (1 << 6) +#define M_RD_REQ (1 << 5) +#define M_TX_EMPTY (1 << 4) +#define M_TX_OVER (1 << 3) +#define M_RX_FULL (1 << 2) +#define M_RX_OVER (1 << 1) +#define M_RX_UNDER (1 << 0) + +/* Raw Interrupt Status Register */ +#define IC_RAW_INTR_STAT 0x34 /* Read Only */ +#define GEN_CALL (1 << 11) /* General call */ +#define START_DET (1 << 10) /* (RE)START occurred */ +#define STOP_DET (1 << 9) /* STOP occurred */ +#define ACTIVITY (1 << 8) /* Bus busy */ +#define RX_DONE (1 << 7) /* Not used in Master mode */ +#define TX_ABRT (1 << 6) /* Transmit Abort */ +#define RD_REQ (1 << 5) /* Not used in Master mode */ +#define TX_EMPTY (1 << 4) /* TX FIFO <= threshold */ +#define TX_OVER (1 << 3) /* TX FIFO overflow */ +#define RX_FULL (1 << 2) /* RX FIFO >= threshold */ +#define RX_OVER (1 << 1) /* RX FIFO overflow */ +#define RX_UNDER (1 << 0) /* RX FIFO empty */ + +/* Receive FIFO Threshold Register */ +#define IC_RX_TL 0x38 + +/* Transmit FIFO Treshold Register */ +#define IC_TX_TL 0x3c + +/* Clear Combined and Individual Interrupt Register */ +#define IC_CLR_INTR 0x40 +#define CLR_INTR (1 << 0) + +/* Clear RX_UNDER Interrupt Register */ +#define IC_CLR_RX_UNDER 0x44 +#define CLR_RX_UNDER (1 << 0) + +/* Clear RX_OVER Interrupt Register */ +#define IC_CLR_RX_OVER 0x48 +#define CLR_RX_OVER (1 << 0) + +/* Clear TX_OVER Interrupt Register */ +#define IC_CLR_TX_OVER 0x4c +#define CLR_TX_OVER (1 << 0) + +#define IC_CLR_RD_REQ 0x50 + +/* Clear TX_ABRT Interrupt Register */ +#define IC_CLR_TX_ABRT 0x54 +#define CLR_TX_ABRT (1 << 0) +#define IC_CLR_RX_DONE 0x58 + +/* Clear ACTIVITY Interrupt Register */ +#define IC_CLR_ACTIVITY 0x5c +#define CLR_ACTIVITY (1 << 0) + +/* Clear STOP_DET Interrupt Register */ +#define IC_CLR_STOP_DET 0x60 +#define CLR_STOP_DET (1 << 0) + +/* Clear START_DET Interrupt Register */ +#define IC_CLR_START_DET 0x64 +#define CLR_START_DET (1 << 0) + +/* Clear GEN_CALL Interrupt Register */ +#define IC_CLR_GEN_CALL 0x68 +#define CLR_GEN_CALL (1 << 0) + +/* Enable Register */ +#define IC_ENABLE 0x6c +#define ENABLE (1 << 0) + +/* Status Register */ +#define IC_STATUS 0x70 /* Read Only */ +#define STAT_SLV_ACTIVITY (1 << 6) /* Slave not in idle */ +#define STAT_MST_ACTIVITY (1 << 5) /* Master not in idle */ +#define STAT_RFF (1 << 4) /* RX FIFO Full */ +#define STAT_RFNE (1 << 3) /* RX FIFO Not Empty */ +#define STAT_TFE (1 << 2) /* TX FIFO Empty */ +#define STAT_TFNF (1 << 1) /* TX FIFO Not Full */ +#define STAT_ACTIVITY (1 << 0) /* Activity Status */ + +/* Transmit FIFO Level Register */ +#define IC_TXFLR 0x74 /* Read Only */ +#define TXFLR (1 << 0) /* TX FIFO level */ + +/* Receive FIFO Level Register */ +#define IC_RXFLR 0x78 /* Read Only */ +#define RXFLR (1 << 0) /* RX FIFO level */ + +/* Transmit Abort Source Register */ +#define IC_TX_ABRT_SOURCE 0x80 +#define ABRT_SLVRD_INTX (1 << 15) +#define ABRT_SLV_ARBLOST (1 << 14) +#define ABRT_SLVFLUSH_TXFIFO (1 << 13) +#define ARB_LOST (1 << 12) +#define ABRT_MASTER_DIS (1 << 11) +#define ABRT_10B_RD_NORSTRT (1 << 10) +#define ABRT_SBYTE_NORSTRT (1 << 9) +#define ABRT_HS_NORSTRT (1 << 8) +#define ABRT_SBYTE_ACKDET (1 << 7) +#define ABRT_HS_ACKDET (1 << 6) +#define ABRT_GCALL_READ (1 << 5) +#define ABRT_GCALL_NOACK (1 << 4) +#define ABRT_TXDATA_NOACK (1 << 3) +#define ABRT_10ADDR2_NOACK (1 << 2) +#define ABRT_10ADDR1_NOACK (1 << 1) +#define ABRT_7B_ADDR_NOACK (1 << 0) + +/* Enable Status Register */ +#define IC_ENABLE_STATUS 0x9c +#define IC_EN (1 << 0) /* I2C in an enabled state */ + +/* Component Parameter Register 1*/ +#define IC_COMP_PARAM_1 0xf4 +#define APB_DATA_WIDTH (0x3 << 0) + +/* added by xiaolin --begin */ +#define SS_MIN_SCL_HIGH 4000 +#define SS_MIN_SCL_LOW 4700 +#define FS_MIN_SCL_HIGH 600 +#define FS_MIN_SCL_LOW 1300 +#define HS_MIN_SCL_HIGH_100PF 60 +#define HS_MIN_SCL_LOW_100PF 120 + +#define STANDARD 0 +#define FAST 1 +#define HIGH 2 + +#define NUM_SPEEDS 3 + +static int speed_mode[6] = { + FAST, + FAST, + FAST, + STANDARD, + FAST, + FAST +}; + +static int ctl_num = 6; +module_param_array(speed_mode, int, &ctl_num, S_IRUGO); +MODULE_PARM_DESC(speed_mode, "Set the speed of the i2c interface (0-2)"); + +/** + * intel_mid_i2c_disable - Disable I2C controller + * @adap: struct pointer to i2c_adapter + * + * Return Value: + * 0 success + * -EBUSY if device is busy + * -ETIMEDOUT if i2c cannot be disabled within the given time + * + * I2C bus state should be checked prior to disabling the hardware. If bus is + * not in idle state, an errno is returned. Write "0" to IC_ENABLE to disable + * I2C controller. + */ +static int intel_mid_i2c_disable(struct i2c_adapter *adap) +{ + struct intel_mid_i2c_private *i2c = i2c_get_adapdata(adap); + int err = 0; + int count = 0; + int ret1, ret2; + static const u16 delay[NUM_SPEEDS] = {100, 25, 3}; + + /* Set IC_ENABLE to 0 */ + writel(0, i2c->base + IC_ENABLE); + + /* Check if device is busy */ + dev_dbg(&adap->dev, "mrst i2c disable\n"); + while ((ret1 = readl(i2c->base + IC_ENABLE_STATUS) & 0x1) + || (ret2 = readl(i2c->base + IC_STATUS) & 0x1)) { + udelay(delay[i2c->speed]); + writel(0, i2c->base + IC_ENABLE); + dev_dbg(&adap->dev, "i2c is busy, count is %d speed %d\n", + count, i2c->speed); + if (count++ > 10) { + err = -ETIMEDOUT; + break; + } + } + + /* Clear all interrupts */ + readl(i2c->base + IC_CLR_INTR); + readl(i2c->base + IC_CLR_STOP_DET); + readl(i2c->base + IC_CLR_START_DET); + readl(i2c->base + IC_CLR_ACTIVITY); + readl(i2c->base + IC_CLR_TX_ABRT); + readl(i2c->base + IC_CLR_RX_OVER); + readl(i2c->base + IC_CLR_RX_UNDER); + readl(i2c->base + IC_CLR_TX_OVER); + readl(i2c->base + IC_CLR_RX_DONE); + readl(i2c->base + IC_CLR_GEN_CALL); + + /* Disable all interupts */ + writel(0x0000, i2c->base + IC_INTR_MASK); + + return err; +} + +/** + * intel_mid_i2c_hwinit - Initialize the I2C hardware registers + * @dev: pci device struct pointer + * + * This function will be called in intel_mid_i2c_probe() before device + * registration. + * + * Return Values: + * 0 success + * -EBUSY i2c cannot be disabled + * -ETIMEDOUT i2c cannot be disabled + * -EFAULT If APB data width is not 32-bit wide + * + * I2C should be disabled prior to other register operation. If failed, an + * errno is returned. Mask and Clear all interrpts, this should be done at + * first. Set common registers which will not be modified during normal + * transfers, including: control register, FIFO threshold and clock freq. + * Check APB data width at last. + */ +static int intel_mid_i2c_hwinit(struct intel_mid_i2c_private *i2c) +{ + int err; + + static const u16 hcnt[NUM_PLATFORMS][NUM_SPEEDS] = { + { 0x75, 0x15, 0x07 }, + { 0x04c, 0x10, 0x06 } + }; + static const u16 lcnt[NUM_PLATFORMS][NUM_SPEEDS] = { + { 0x7C, 0x21, 0x0E }, + { 0x053, 0x19, 0x0F } + }; + + /* Disable i2c first */ + err = intel_mid_i2c_disable(&i2c->adap); + if (err) + return err; + + /* + * Setup clock frequency and speed mode + * Enable restart condition, + * enable master FSM, disable slave FSM, + * use target address when initiating transfer + */ + + writel((i2c->speed + 1) << 1 | SLV_DIS | RESTART | MASTER_EN, + i2c->base + IC_CON); + writel(hcnt[i2c->platform][i2c->speed], + i2c->base + (IC_SS_SCL_HCNT + (i2c->speed << 3))); + writel(lcnt[i2c->platform][i2c->speed], + i2c->base + (IC_SS_SCL_LCNT + (i2c->speed << 3))); + + /* Set tranmit & receive FIFO threshold to zero */ + writel(0x0, i2c->base + IC_RX_TL); + writel(0x0, i2c->base + IC_TX_TL); + + return 0; +} + +/** + * intel_mid_i2c_func - Return the supported three I2C operations. + * @adapter: i2c_adapter struct pointer + */ +static u32 intel_mid_i2c_func(struct i2c_adapter *adapter) +{ + return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SMBUS_EMUL; +} + +/** + * intel_mid_i2c_address_neq - To check if the addresses for different i2c messages + * are equal. + * @p1: first i2c_msg + * @p2: second i2c_msg + * + * Return Values: + * 0 if addresses are equal + * 1 if not equal + * + * Within a single transfer, the I2C client may need to send its address more + * than once. So a check if the addresses match is needed. + */ +static inline bool intel_mid_i2c_address_neq(const struct i2c_msg *p1, + const struct i2c_msg *p2) +{ + if (p1->addr != p2->addr) + return 1; + if ((p1->flags ^ p2->flags) & I2C_M_TEN) + return 1; + return 0; +} + +/** + * intel_mid_i2c_abort - To handle transfer abortions and print error messages. + * @adap: i2c_adapter struct pointer + * + * By reading register IC_TX_ABRT_SOURCE, various transfer errors can be + * distingushed. At present, no circumstances have been found out that + * multiple errors would be occurred simutaneously, so we simply use the + * register value directly. + * + * At last the error bits are cleared. (Note clear ABRT_SBYTE_NORSTRT bit need + * a few extra steps) + */ +static void intel_mid_i2c_abort(struct intel_mid_i2c_private *i2c) +{ + /* Read about source register */ + int abort = i2c->abort; + struct i2c_adapter *adap = &i2c->adap; + + /* Single transfer error check: + * According to databook, TX/RX FIFOs would be flushed when + * the abort interrupt occurred. + */ + if (abort & ABRT_MASTER_DIS) + dev_err(&adap->dev, + "initiate master operation with master mode disabled.\n"); + if (abort & ABRT_10B_RD_NORSTRT) + dev_err(&adap->dev, + "RESTART disabled and master sent READ cmd in 10-bit addressing.\n"); + + if (abort & ABRT_SBYTE_NORSTRT) { + dev_err(&adap->dev, + "RESTART disabled and user is trying to send START byte.\n"); + writel(~ABRT_SBYTE_NORSTRT, i2c->base + IC_TX_ABRT_SOURCE); + writel(RESTART, i2c->base + IC_CON); + writel(~IC_TAR_SPECIAL, i2c->base + IC_TAR); + } + + if (abort & ABRT_SBYTE_ACKDET) + dev_err(&adap->dev, + "START byte was not acknowledged.\n"); + if (abort & ABRT_TXDATA_NOACK) + dev_dbg(&adap->dev, + "No acknowledgement received from slave.\n"); + if (abort & ABRT_10ADDR2_NOACK) + dev_dbg(&adap->dev, + "The 2nd address byte of the 10-bit address was not acknowledged.\n"); + if (abort & ABRT_10ADDR1_NOACK) + dev_dbg(&adap->dev, + "The 1st address byte of 10-bit address was not acknowledged.\n"); + if (abort & ABRT_7B_ADDR_NOACK) + dev_dbg(&adap->dev, + "I2C slave device not acknowledged.\n"); + + /* Clear TX_ABRT bit */ + readl(i2c->base + IC_CLR_TX_ABRT); + i2c->status = STATUS_XFER_ABORT; +} + +/** + * xfer_read - Internal function to implement master read transfer. + * @adap: i2c_adapter struct pointer + * @buf: buffer in i2c_msg + * @length: number of bytes to be read + * + * Return Values: + * 0 if the read transfer succeeds + * -ETIMEDOUT if cannot read the "raw" interrupt register + * -EINVAL if a transfer abort occurred + * + * For every byte, a "READ" command will be loaded into IC_DATA_CMD prior to + * data transfer. The actual "read" operation will be performed if an RX_FULL + * interrupt occurred. + * + * Note there may be two interrupt signals captured, one should read + * IC_RAW_INTR_STAT to separate between errors and actual data. + */ +static int xfer_read(struct i2c_adapter *adap, unsigned char *buf, int length) +{ + struct intel_mid_i2c_private *i2c = i2c_get_adapdata(adap); + int i = length; + int err; + + if (length >= 256) { + dev_err(&adap->dev, + "I2C FIFO cannot support larger than 256 bytes\n"); + return -EMSGSIZE; + } + + INIT_COMPLETION(i2c->complete); + + readl(i2c->base + IC_CLR_INTR); + writel(0x0044, i2c->base + IC_INTR_MASK); + + i2c->status = STATUS_READ_START; + + while (i--) + writel(IC_RD, i2c->base + IC_DATA_CMD); + + i2c->status = STATUS_READ_START; + err = wait_for_completion_interruptible_timeout(&i2c->complete, HZ); + if (!err) { + dev_err(&adap->dev, "Timeout for ACK from I2C slave device\n"); + intel_mid_i2c_hwinit(i2c); + return -ETIMEDOUT; + } + if (i2c->status == STATUS_READ_SUCCESS) + return 0; + else + return -EIO; +} + +/** + * xfer_write - Internal function to implement master write transfer. + * @adap: i2c_adapter struct pointer + * @buf: buffer in i2c_msg + * @length: number of bytes to be read + * + * Return Values: + * 0 if the read transfer succeeds + * -ETIMEDOUT if we cannot read the "raw" interrupt register + * -EINVAL if a transfer abort occurred + * + * For every byte, a "WRITE" command will be loaded into IC_DATA_CMD prior to + * data transfer. The actual "write" operation will be performed when the + * RX_FULL interrupt signal occurs. + * + * Note there may be two interrupt signals captured, one should read + * IC_RAW_INTR_STAT to separate between errors and actual data. + */ +static int xfer_write(struct i2c_adapter *adap, + unsigned char *buf, int length) +{ + struct intel_mid_i2c_private *i2c = i2c_get_adapdata(adap); + int i, err; + + if (length >= 256) { + dev_err(&adap->dev, + "I2C FIFO cannot support larger than 256 bytes\n"); + return -EMSGSIZE; + } + + INIT_COMPLETION(i2c->complete); + + readl(i2c->base + IC_CLR_INTR); + writel(0x0050, i2c->base + IC_INTR_MASK); + + i2c->status = STATUS_WRITE_START; + for (i = 0; i < length; i++) + writel((u16)(*(buf + i)), i2c->base + IC_DATA_CMD); + + i2c->status = STATUS_WRITE_START; + err = wait_for_completion_interruptible_timeout(&i2c->complete, HZ); + if (!err) { + dev_err(&adap->dev, "Timeout for ACK from I2C slave device\n"); + intel_mid_i2c_hwinit(i2c); + return -ETIMEDOUT; + } else { + if (i2c->status == STATUS_WRITE_SUCCESS) + return 0; + else + return -EIO; + } +} + +static int intel_mid_i2c_setup(struct i2c_adapter *adap, struct i2c_msg *pmsg) +{ + struct intel_mid_i2c_private *i2c = i2c_get_adapdata(adap); + int err; + u32 reg; + u32 bit_mask; + u32 mode; + + /* Disable device first */ + err = intel_mid_i2c_disable(adap); + if (err) { + dev_err(&adap->dev, + "Cannot disable i2c controller, timeout\n"); + return err; + } + + mode = (1 + i2c->speed) << 1; + /* set the speed mode */ + reg = readl(i2c->base + IC_CON); + if ((reg & 0x06) != mode) { + dev_dbg(&adap->dev, "set mode %d\n", i2c->speed); + writel((reg & ~0x6) | mode, i2c->base + IC_CON); + } + + reg = readl(i2c->base + IC_CON); + /* use 7-bit addressing */ + if (pmsg->flags & I2C_M_TEN) { + if ((reg & ADDR_10BIT) != ADDR_10BIT) { + dev_dbg(&adap->dev, "set i2c 10 bit address mode\n"); + writel(reg | ADDR_10BIT, i2c->base + IC_CON); + } + } else { + if ((reg & ADDR_10BIT) != 0x0) { + dev_dbg(&adap->dev, "set i2c 7 bit address mode\n"); + writel(reg & ~ADDR_10BIT, i2c->base + IC_CON); + } + } + /* enable restart conditions */ + reg = readl(i2c->base + IC_CON); + if ((reg & RESTART) != RESTART) { + dev_dbg(&adap->dev, "enable restart conditions\n"); + writel(reg | RESTART, i2c->base + IC_CON); + } + + /* enable master FSM */ + reg = readl(i2c->base + IC_CON); + dev_dbg(&adap->dev, "ic_con reg is 0x%x\n", reg); + writel(reg | MASTER_EN, i2c->base + IC_CON); + if ((reg & SLV_DIS) != SLV_DIS) { + dev_dbg(&adap->dev, "enable master FSM\n"); + writel(reg | SLV_DIS, i2c->base + IC_CON); + dev_dbg(&adap->dev, "ic_con reg is 0x%x\n", reg); + } + + /* use target address when initiating transfer */ + reg = readl(i2c->base + IC_TAR); + bit_mask = IC_TAR_SPECIAL | IC_TAR_GC_OR_START; + + if ((reg & bit_mask) != 0x0) { + dev_dbg(&adap->dev, + "WR: use target address when intiating transfer, i2c_tx_target\n"); + writel(reg & ~bit_mask, i2c->base + IC_TAR); + } + + /* set target address to the I2C slave address */ + dev_dbg(&adap->dev, + "set target address to the I2C slave address, addr is %x\n", + pmsg->addr); + writel(pmsg->addr | (pmsg->flags & I2C_M_TEN ? IC_TAR_10BIT_ADDR : 0), + i2c->base + IC_TAR); + + /* Enable I2C controller */ + writel(ENABLE, i2c->base + IC_ENABLE); + + return 0; +} + +/** + * intel_mid_i2c_xfer - Main master transfer routine. + * @adap: i2c_adapter struct pointer + * @pmsg: i2c_msg struct pointer + * @num: number of i2c_msg + * + * Return Values: + * + number of messages transferred + * -ETIMEDOUT If cannot disable I2C controller or read IC_STATUS + * -EINVAL If the address in i2c_msg is invalid + * + * This function will be registered in i2c-core and exposed to external + * I2C clients. + * 1. Disable I2C controller + * 2. Unmask three interrupts: RX_FULL, TX_EMPTY, TX_ABRT + * 3. Check if address in i2c_msg is valid + * 4. Enable I2C controller + * 5. Perform real transfer (call xfer_read or xfer_write) + * 6. Wait until the current transfer is finished (check bus state) + * 7. Mask and clear all interrupts + */ +static int intel_mid_i2c_xfer(struct i2c_adapter *adap, + struct i2c_msg *pmsg, + int num) +{ + struct intel_mid_i2c_private *i2c = i2c_get_adapdata(adap); + int i, err = 0; + + /* if number of messages equal 0*/ + if (num == 0) + return 0; + + pm_runtime_get(i2c->dev); + + mutex_lock(&i2c->lock); + dev_dbg(&adap->dev, "intel_mid_i2c_xfer, process %d msg(s)\n", num); + dev_dbg(&adap->dev, "slave address is %x\n", pmsg->addr); + + + if (i2c->status != STATUS_IDLE) { + dev_err(&adap->dev, "Adapter %d in transfer/standby\n", + adap->nr); + mutex_unlock(&i2c->lock); + pm_runtime_put(i2c->dev); + return -1; + } + + + for (i = 1; i < num; i++) { + /* Message address equal? */ + if (unlikely(intel_mid_i2c_address_neq(&pmsg[0], &pmsg[i]))) { + dev_err(&adap->dev, "Invalid address in msg[%d]\n", i); + mutex_unlock(&i2c->lock); + pm_runtime_put(i2c->dev); + return -EINVAL; + } + } + + if (intel_mid_i2c_setup(adap, pmsg)) { + mutex_unlock(&i2c->lock); + pm_runtime_put(i2c->dev); + return -EINVAL; + } + + for (i = 0; i < num; i++) { + i2c->msg = pmsg; + i2c->status = STATUS_IDLE; + /* Read or Write */ + if (pmsg->flags & I2C_M_RD) { + dev_dbg(&adap->dev, "I2C_M_RD\n"); + err = xfer_read(adap, pmsg->buf, pmsg->len); + } else { + dev_dbg(&adap->dev, "I2C_M_WR\n"); + err = xfer_write(adap, pmsg->buf, pmsg->len); + } + if (err < 0) + break; + dev_dbg(&adap->dev, "msg[%d] transfer complete\n", i); + pmsg++; /* next message */ + } + + /* Mask interrupts */ + writel(0x0000, i2c->base + IC_INTR_MASK); + /* Clear all interrupts */ + readl(i2c->base + IC_CLR_INTR); + + i2c->status = STATUS_IDLE; + mutex_unlock(&i2c->lock); + pm_runtime_put(i2c->dev); + + return err; +} + +static int intel_mid_i2c_runtime_suspend(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct intel_mid_i2c_private *i2c = pci_get_drvdata(pdev); + struct i2c_adapter *adap = to_i2c_adapter(dev); + int err; + + if (i2c->status != STATUS_IDLE) + return -1; + + intel_mid_i2c_disable(adap); + + err = pci_save_state(pdev); + if (err) { + dev_err(dev, "pci_save_state failed\n"); + return err; + } + + err = pci_set_power_state(pdev, PCI_D3hot); + if (err) { + dev_err(dev, "pci_set_power_state failed\n"); + return err; + } + i2c->status = STATUS_STANDBY; + + return 0; +} + +static int intel_mid_i2c_runtime_resume(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct intel_mid_i2c_private *i2c = pci_get_drvdata(pdev); + int err; + + if (i2c->status != STATUS_STANDBY) + return 0; + + pci_set_power_state(pdev, PCI_D0); + pci_restore_state(pdev); + err = pci_enable_device(pdev); + if (err) { + dev_err(dev, "pci_enable_device failed\n"); + return err; + } + + i2c->status = STATUS_IDLE; + + intel_mid_i2c_hwinit(i2c); + return err; +} + +static void i2c_isr_read(struct intel_mid_i2c_private *i2c) +{ + struct i2c_msg *msg = i2c->msg; + int rx_num; + u32 len; + u8 *buf; + + if (!(msg->flags & I2C_M_RD)) + return; + + if (i2c->status != STATUS_READ_IN_PROGRESS) { + len = msg->len; + buf = msg->buf; + } else { + len = i2c->rx_buf_len; + buf = i2c->rx_buf; + } + + rx_num = readl(i2c->base + IC_RXFLR); + + for (; len > 0 && rx_num > 0; len--, rx_num--) + *buf++ = readl(i2c->base + IC_DATA_CMD); + + if (len > 0) { + i2c->status = STATUS_READ_IN_PROGRESS; + i2c->rx_buf_len = len; + i2c->rx_buf = buf; + } else + i2c->status = STATUS_READ_SUCCESS; + + return; +} + +static irqreturn_t intel_mid_i2c_isr(int this_irq, void *dev) +{ + struct intel_mid_i2c_private *i2c = dev; + u32 stat = readl(i2c->base + IC_INTR_STAT); + + if (!stat) + return IRQ_NONE; + + dev_dbg(&i2c->adap.dev, "%s, stat = 0x%x\n", __func__, stat); + stat &= 0x54; + + if (i2c->status != STATUS_WRITE_START && + i2c->status != STATUS_READ_START && + i2c->status != STATUS_READ_IN_PROGRESS) + goto err; + + if (stat & TX_ABRT) + i2c->abort = readl(i2c->base + IC_TX_ABRT_SOURCE); + + readl(i2c->base + IC_CLR_INTR); + + if (stat & TX_ABRT) { + intel_mid_i2c_abort(i2c); + goto exit; + } + + if (stat & RX_FULL) { + i2c_isr_read(i2c); + goto exit; + } + + if (stat & TX_EMPTY) { + if (readl(i2c->base + IC_STATUS) & 0x4) + i2c->status = STATUS_WRITE_SUCCESS; + } + +exit: + if (i2c->status == STATUS_READ_SUCCESS || + i2c->status == STATUS_WRITE_SUCCESS || + i2c->status == STATUS_XFER_ABORT) { + /* Clear all interrupts */ + readl(i2c->base + IC_CLR_INTR); + /* Mask interrupts */ + writel(0, i2c->base + IC_INTR_MASK); + complete(&i2c->complete); + } +err: + return IRQ_HANDLED; +} + +static struct i2c_algorithm intel_mid_i2c_algorithm = { + .master_xfer = intel_mid_i2c_xfer, + .functionality = intel_mid_i2c_func, +}; + + +static const struct dev_pm_ops intel_mid_i2c_pm_ops = { + .runtime_suspend = intel_mid_i2c_runtime_suspend, + .runtime_resume = intel_mid_i2c_runtime_resume, +}; + +/** + * intel_mid_i2c_probe - I2C controller initialization routine + * @dev: pci device + * @id: device id + * + * Return Values: + * 0 success + * -ENODEV If cannot allocate pci resource + * -ENOMEM If the register base remapping failed, or + * if kzalloc failed + * + * Initialization steps: + * 1. Request for PCI resource + * 2. Remap the start address of PCI resource to register base + * 3. Request for device memory region + * 4. Fill in the struct members of intel_mid_i2c_private + * 5. Call intel_mid_i2c_hwinit() for hardware initialization + * 6. Register I2C adapter in i2c-core + */ +static int __devinit intel_mid_i2c_probe(struct pci_dev *dev, + const struct pci_device_id *id) +{ + struct intel_mid_i2c_private *mrst; + unsigned long start, len; + int err, busnum; + void __iomem *base = NULL; + + dev_dbg(&dev->dev, "Get into probe function for I2C\n"); + err = pci_enable_device(dev); + if (err) { + dev_err(&dev->dev, "Failed to enable I2C PCI device (%d)\n", + err); + goto exit; + } + + /* Determine the address of the I2C area */ + start = pci_resource_start(dev, 0); + len = pci_resource_len(dev, 0); + if (!start || len == 0) { + dev_err(&dev->dev, "base address not set\n"); + err = -ENODEV; + goto exit; + } + dev_dbg(&dev->dev, "%s i2c resource start 0x%lx, len=%ld\n", + PLATFORM, start, len); + + err = pci_request_region(dev, 0, DRIVER_NAME); + if (err) { + dev_err(&dev->dev, "failed to request I2C region " + "0x%lx-0x%lx\n", start, + (unsigned long)pci_resource_end(dev, 0)); + goto exit; + } + + base = ioremap_nocache(start, len); + if (!base) { + dev_err(&dev->dev, "I/O memory remapping failed\n"); + err = -ENOMEM; + goto fail0; + } + + /* Allocate the per-device data structure, intel_mid_i2c_private */ + mrst = kzalloc(sizeof(struct intel_mid_i2c_private), GFP_KERNEL); + if (mrst == NULL) { + dev_err(&dev->dev, "can't allocate interface\n"); + err = -ENOMEM; + goto fail1; + } + + /* Initialize struct members */ + snprintf(mrst->adap.name, sizeof(mrst->adap.name), + "Intel MID I2C at %lx", start); + mrst->adap.owner = THIS_MODULE; + mrst->adap.algo = &intel_mid_i2c_algorithm; + mrst->adap.dev.parent = &dev->dev; + mrst->dev = &dev->dev; + mrst->base = base; + mrst->speed = STANDARD; + mrst->abort = 0; + mrst->rx_buf_len = 0; + mrst->status = STATUS_IDLE; + + pci_set_drvdata(dev, mrst); + i2c_set_adapdata(&mrst->adap, mrst); + + mrst->adap.nr = busnum = id->driver_data; + if (dev->device <= 0x0804) + mrst->platform = MOORESTOWN; + else + mrst->platform = MEDFIELD; + + dev_dbg(&dev->dev, "I2C%d\n", busnum); + + if (ctl_num > busnum) { + if (speed_mode[busnum] < 0 || speed_mode[busnum] >= NUM_SPEEDS) + dev_warn(&dev->dev, "invalid speed %d ignored.\n", + speed_mode[busnum]); + else + mrst->speed = speed_mode[busnum]; + } + + /* Initialize i2c controller */ + err = intel_mid_i2c_hwinit(mrst); + if (err < 0) { + dev_err(&dev->dev, "I2C interface initialization failed\n"); + goto fail2; + } + + mutex_init(&mrst->lock); + init_completion(&mrst->complete); + + /* Clear all interrupts */ + readl(mrst->base + IC_CLR_INTR); + writel(0x0000, mrst->base + IC_INTR_MASK); + + err = request_irq(dev->irq, intel_mid_i2c_isr, IRQF_SHARED, + mrst->adap.name, mrst); + if (err) { + dev_err(&dev->dev, "Failed to request IRQ for I2C controller: " + "%s", mrst->adap.name); + goto fail2; + } + + /* Adapter registration */ + err = i2c_add_numbered_adapter(&mrst->adap); + if (err) { + dev_err(&dev->dev, "Adapter %s registration failed\n", + mrst->adap.name); + goto fail3; + } + + dev_dbg(&dev->dev, "%s I2C bus %d driver bind success.\n", + (mrst->platform == MOORESTOWN) ? "Moorestown" : "Medfield", + busnum); + + pm_runtime_enable(&dev->dev); + return 0; + +fail3: + free_irq(dev->irq, mrst); +fail2: + pci_set_drvdata(dev, NULL); + kfree(mrst); +fail1: + iounmap(base); +fail0: + pci_release_region(dev, 0); +exit: + return err; +} + +static void __devexit intel_mid_i2c_remove(struct pci_dev *dev) +{ + struct intel_mid_i2c_private *mrst = pci_get_drvdata(dev); + intel_mid_i2c_disable(&mrst->adap); + if (i2c_del_adapter(&mrst->adap)) + dev_err(&dev->dev, "Failed to delete i2c adapter"); + + free_irq(dev->irq, mrst); + pci_set_drvdata(dev, NULL); + iounmap(mrst->base); + kfree(mrst); + pci_release_region(dev, 0); +} + +static struct pci_device_id intel_mid_i2c_ids[] = { + /* Moorestown */ + { PCI_VDEVICE(INTEL, 0x0802), 0 }, + { PCI_VDEVICE(INTEL, 0x0803), 1 }, + { PCI_VDEVICE(INTEL, 0x0804), 2 }, + /* Medfield */ + { PCI_VDEVICE(INTEL, 0x0817), 3,}, + { PCI_VDEVICE(INTEL, 0x0818), 4 }, + { PCI_VDEVICE(INTEL, 0x0819), 5 }, + { PCI_VDEVICE(INTEL, 0x082C), 0 }, + { PCI_VDEVICE(INTEL, 0x082D), 1 }, + { PCI_VDEVICE(INTEL, 0x082E), 2 }, + { 0,} +}; +MODULE_DEVICE_TABLE(pci, intel_mid_i2c_ids); + +static struct pci_driver intel_mid_i2c_driver = { + .name = DRIVER_NAME, + .id_table = intel_mid_i2c_ids, + .probe = intel_mid_i2c_probe, + .remove = __devexit_p(intel_mid_i2c_remove), +}; + +static int __init intel_mid_i2c_init(void) +{ + return pci_register_driver(&intel_mid_i2c_driver); +} + +static void __exit intel_mid_i2c_exit(void) +{ + pci_unregister_driver(&intel_mid_i2c_driver); +} + +module_init(intel_mid_i2c_init); +module_exit(intel_mid_i2c_exit); + +MODULE_AUTHOR("Ba Zheng <zheng.ba@intel.com>"); +MODULE_DESCRIPTION("I2C driver for Moorestown Platform"); +MODULE_LICENSE("GPL"); +MODULE_VERSION(VERSION); |