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linux-zen-desktop/drivers/i2c/busses/i2c-qup.c

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2023-08-30 17:31:07 +02:00
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2009-2013, 2016-2018, The Linux Foundation. All rights reserved.
* Copyright (c) 2014, Sony Mobile Communications AB.
*
*/
#include <linux/acpi.h>
#include <linux/atomic.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/dmaengine.h>
#include <linux/dmapool.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/scatterlist.h>
/* QUP Registers */
#define QUP_CONFIG 0x000
#define QUP_STATE 0x004
#define QUP_IO_MODE 0x008
#define QUP_SW_RESET 0x00c
#define QUP_OPERATIONAL 0x018
#define QUP_ERROR_FLAGS 0x01c
#define QUP_ERROR_FLAGS_EN 0x020
#define QUP_OPERATIONAL_MASK 0x028
#define QUP_HW_VERSION 0x030
#define QUP_MX_OUTPUT_CNT 0x100
#define QUP_OUT_FIFO_BASE 0x110
#define QUP_MX_WRITE_CNT 0x150
#define QUP_MX_INPUT_CNT 0x200
#define QUP_MX_READ_CNT 0x208
#define QUP_IN_FIFO_BASE 0x218
#define QUP_I2C_CLK_CTL 0x400
#define QUP_I2C_STATUS 0x404
#define QUP_I2C_MASTER_GEN 0x408
/* QUP States and reset values */
#define QUP_RESET_STATE 0
#define QUP_RUN_STATE 1
#define QUP_PAUSE_STATE 3
#define QUP_STATE_MASK 3
#define QUP_STATE_VALID BIT(2)
#define QUP_I2C_MAST_GEN BIT(4)
#define QUP_I2C_FLUSH BIT(6)
#define QUP_OPERATIONAL_RESET 0x000ff0
#define QUP_I2C_STATUS_RESET 0xfffffc
/* QUP OPERATIONAL FLAGS */
#define QUP_I2C_NACK_FLAG BIT(3)
#define QUP_OUT_NOT_EMPTY BIT(4)
#define QUP_IN_NOT_EMPTY BIT(5)
#define QUP_OUT_FULL BIT(6)
#define QUP_OUT_SVC_FLAG BIT(8)
#define QUP_IN_SVC_FLAG BIT(9)
#define QUP_MX_OUTPUT_DONE BIT(10)
#define QUP_MX_INPUT_DONE BIT(11)
#define OUT_BLOCK_WRITE_REQ BIT(12)
#define IN_BLOCK_READ_REQ BIT(13)
/* I2C mini core related values */
#define QUP_NO_INPUT BIT(7)
#define QUP_CLOCK_AUTO_GATE BIT(13)
#define I2C_MINI_CORE (2 << 8)
#define I2C_N_VAL 15
#define I2C_N_VAL_V2 7
/* Most significant word offset in FIFO port */
#define QUP_MSW_SHIFT (I2C_N_VAL + 1)
/* Packing/Unpacking words in FIFOs, and IO modes */
#define QUP_OUTPUT_BLK_MODE (1 << 10)
#define QUP_OUTPUT_BAM_MODE (3 << 10)
#define QUP_INPUT_BLK_MODE (1 << 12)
#define QUP_INPUT_BAM_MODE (3 << 12)
#define QUP_BAM_MODE (QUP_OUTPUT_BAM_MODE | QUP_INPUT_BAM_MODE)
#define QUP_UNPACK_EN BIT(14)
#define QUP_PACK_EN BIT(15)
#define QUP_REPACK_EN (QUP_UNPACK_EN | QUP_PACK_EN)
#define QUP_V2_TAGS_EN 1
#define QUP_OUTPUT_BLOCK_SIZE(x)(((x) >> 0) & 0x03)
#define QUP_OUTPUT_FIFO_SIZE(x) (((x) >> 2) & 0x07)
#define QUP_INPUT_BLOCK_SIZE(x) (((x) >> 5) & 0x03)
#define QUP_INPUT_FIFO_SIZE(x) (((x) >> 7) & 0x07)
/* QUP tags */
#define QUP_TAG_START (1 << 8)
#define QUP_TAG_DATA (2 << 8)
#define QUP_TAG_STOP (3 << 8)
#define QUP_TAG_REC (4 << 8)
#define QUP_BAM_INPUT_EOT 0x93
#define QUP_BAM_FLUSH_STOP 0x96
/* QUP v2 tags */
#define QUP_TAG_V2_START 0x81
#define QUP_TAG_V2_DATAWR 0x82
#define QUP_TAG_V2_DATAWR_STOP 0x83
#define QUP_TAG_V2_DATARD 0x85
#define QUP_TAG_V2_DATARD_NACK 0x86
#define QUP_TAG_V2_DATARD_STOP 0x87
/* Status, Error flags */
#define I2C_STATUS_WR_BUFFER_FULL BIT(0)
#define I2C_STATUS_BUS_ACTIVE BIT(8)
#define I2C_STATUS_ERROR_MASK 0x38000fc
#define QUP_STATUS_ERROR_FLAGS 0x7c
#define QUP_READ_LIMIT 256
#define SET_BIT 0x1
#define RESET_BIT 0x0
#define ONE_BYTE 0x1
#define QUP_I2C_MX_CONFIG_DURING_RUN BIT(31)
/* Maximum transfer length for single DMA descriptor */
#define MX_TX_RX_LEN SZ_64K
#define MX_BLOCKS (MX_TX_RX_LEN / QUP_READ_LIMIT)
/* Maximum transfer length for all DMA descriptors */
#define MX_DMA_TX_RX_LEN (2 * MX_TX_RX_LEN)
#define MX_DMA_BLOCKS (MX_DMA_TX_RX_LEN / QUP_READ_LIMIT)
/*
* Minimum transfer timeout for i2c transfers in seconds. It will be added on
* the top of maximum transfer time calculated from i2c bus speed to compensate
* the overheads.
*/
#define TOUT_MIN 2
/* Default values. Use these if FW query fails */
#define DEFAULT_CLK_FREQ I2C_MAX_STANDARD_MODE_FREQ
#define DEFAULT_SRC_CLK 20000000
/*
* Max tags length (start, stop and maximum 2 bytes address) for each QUP
* data transfer
*/
#define QUP_MAX_TAGS_LEN 4
/* Max data length for each DATARD tags */
#define RECV_MAX_DATA_LEN 254
/* TAG length for DATA READ in RX FIFO */
#define READ_RX_TAGS_LEN 2
static unsigned int scl_freq;
module_param_named(scl_freq, scl_freq, uint, 0444);
MODULE_PARM_DESC(scl_freq, "SCL frequency override");
/*
* count: no of blocks
* pos: current block number
* tx_tag_len: tx tag length for current block
* rx_tag_len: rx tag length for current block
* data_len: remaining data length for current message
* cur_blk_len: data length for current block
* total_tx_len: total tx length including tag bytes for current QUP transfer
* total_rx_len: total rx length including tag bytes for current QUP transfer
* tx_fifo_data_pos: current byte number in TX FIFO word
* tx_fifo_free: number of free bytes in current QUP block write.
* rx_fifo_data_pos: current byte number in RX FIFO word
* fifo_available: number of available bytes in RX FIFO for current
* QUP block read
* tx_fifo_data: QUP TX FIFO write works on word basis (4 bytes). New byte write
* to TX FIFO will be appended in this data and will be written to
* TX FIFO when all the 4 bytes are available.
* rx_fifo_data: QUP RX FIFO read works on word basis (4 bytes). This will
* contains the 4 bytes of RX data.
* cur_data: pointer to tell cur data position for current message
* cur_tx_tags: pointer to tell cur position in tags
* tx_tags_sent: all tx tag bytes have been written in FIFO word
* send_last_word: for tx FIFO, last word send is pending in current block
* rx_bytes_read: if all the bytes have been read from rx FIFO.
* rx_tags_fetched: all the rx tag bytes have been fetched from rx fifo word
* is_tx_blk_mode: whether tx uses block or FIFO mode in case of non BAM xfer.
* is_rx_blk_mode: whether rx uses block or FIFO mode in case of non BAM xfer.
* tags: contains tx tag bytes for current QUP transfer
*/
struct qup_i2c_block {
int count;
int pos;
int tx_tag_len;
int rx_tag_len;
int data_len;
int cur_blk_len;
int total_tx_len;
int total_rx_len;
int tx_fifo_data_pos;
int tx_fifo_free;
int rx_fifo_data_pos;
int fifo_available;
u32 tx_fifo_data;
u32 rx_fifo_data;
u8 *cur_data;
u8 *cur_tx_tags;
bool tx_tags_sent;
bool send_last_word;
bool rx_tags_fetched;
bool rx_bytes_read;
bool is_tx_blk_mode;
bool is_rx_blk_mode;
u8 tags[6];
};
struct qup_i2c_tag {
u8 *start;
dma_addr_t addr;
};
struct qup_i2c_bam {
struct qup_i2c_tag tag;
struct dma_chan *dma;
struct scatterlist *sg;
unsigned int sg_cnt;
};
struct qup_i2c_dev {
struct device *dev;
void __iomem *base;
int irq;
struct clk *clk;
struct clk *pclk;
struct i2c_adapter adap;
int clk_ctl;
int out_fifo_sz;
int in_fifo_sz;
int out_blk_sz;
int in_blk_sz;
int blk_xfer_limit;
unsigned long one_byte_t;
unsigned long xfer_timeout;
struct qup_i2c_block blk;
struct i2c_msg *msg;
/* Current posion in user message buffer */
int pos;
/* I2C protocol errors */
u32 bus_err;
/* QUP core errors */
u32 qup_err;
/* To check if this is the last msg */
bool is_last;
bool is_smbus_read;
/* To configure when bus is in run state */
u32 config_run;
/* dma parameters */
bool is_dma;
/* To check if the current transfer is using DMA */
bool use_dma;
unsigned int max_xfer_sg_len;
unsigned int tag_buf_pos;
/* The threshold length above which block mode will be used */
unsigned int blk_mode_threshold;
struct dma_pool *dpool;
struct qup_i2c_tag start_tag;
struct qup_i2c_bam brx;
struct qup_i2c_bam btx;
struct completion xfer;
/* function to write data in tx fifo */
void (*write_tx_fifo)(struct qup_i2c_dev *qup);
/* function to read data from rx fifo */
void (*read_rx_fifo)(struct qup_i2c_dev *qup);
/* function to write tags in tx fifo for i2c read transfer */
void (*write_rx_tags)(struct qup_i2c_dev *qup);
};
static irqreturn_t qup_i2c_interrupt(int irq, void *dev)
{
struct qup_i2c_dev *qup = dev;
struct qup_i2c_block *blk = &qup->blk;
u32 bus_err;
u32 qup_err;
u32 opflags;
bus_err = readl(qup->base + QUP_I2C_STATUS);
qup_err = readl(qup->base + QUP_ERROR_FLAGS);
opflags = readl(qup->base + QUP_OPERATIONAL);
if (!qup->msg) {
/* Clear Error interrupt */
writel(QUP_RESET_STATE, qup->base + QUP_STATE);
return IRQ_HANDLED;
}
bus_err &= I2C_STATUS_ERROR_MASK;
qup_err &= QUP_STATUS_ERROR_FLAGS;
/* Clear the error bits in QUP_ERROR_FLAGS */
if (qup_err)
writel(qup_err, qup->base + QUP_ERROR_FLAGS);
/* Clear the error bits in QUP_I2C_STATUS */
if (bus_err)
writel(bus_err, qup->base + QUP_I2C_STATUS);
/*
* Check for BAM mode and returns if already error has come for current
* transfer. In Error case, sometimes, QUP generates more than one
* interrupt.
*/
if (qup->use_dma && (qup->qup_err || qup->bus_err))
return IRQ_HANDLED;
/* Reset the QUP State in case of error */
if (qup_err || bus_err) {
/*
* Don’t reset the QUP state in case of BAM mode. The BAM
* flush operation needs to be scheduled in transfer function
* which will clear the remaining schedule descriptors in BAM
* HW FIFO and generates the BAM interrupt.
*/
if (!qup->use_dma)
writel(QUP_RESET_STATE, qup->base + QUP_STATE);
goto done;
}
if (opflags & QUP_OUT_SVC_FLAG) {
writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL);
if (opflags & OUT_BLOCK_WRITE_REQ) {
blk->tx_fifo_free += qup->out_blk_sz;
if (qup->msg->flags & I2C_M_RD)
qup->write_rx_tags(qup);
else
qup->write_tx_fifo(qup);
}
}
if (opflags & QUP_IN_SVC_FLAG) {
writel(QUP_IN_SVC_FLAG, qup->base + QUP_OPERATIONAL);
if (!blk->is_rx_blk_mode) {
blk->fifo_available += qup->in_fifo_sz;
qup->read_rx_fifo(qup);
} else if (opflags & IN_BLOCK_READ_REQ) {
blk->fifo_available += qup->in_blk_sz;
qup->read_rx_fifo(qup);
}
}
if (qup->msg->flags & I2C_M_RD) {
if (!blk->rx_bytes_read)
return IRQ_HANDLED;
} else {
/*
* Ideally, QUP_MAX_OUTPUT_DONE_FLAG should be checked
* for FIFO mode also. But, QUP_MAX_OUTPUT_DONE_FLAG lags
* behind QUP_OUTPUT_SERVICE_FLAG sometimes. The only reason
* of interrupt for write message in FIFO mode is
* QUP_MAX_OUTPUT_DONE_FLAG condition.
*/
if (blk->is_tx_blk_mode && !(opflags & QUP_MX_OUTPUT_DONE))
return IRQ_HANDLED;
}
done:
qup->qup_err = qup_err;
qup->bus_err = bus_err;
complete(&qup->xfer);
return IRQ_HANDLED;
}
static int qup_i2c_poll_state_mask(struct qup_i2c_dev *qup,
u32 req_state, u32 req_mask)
{
int retries = 1;
u32 state;
/*
* State transition takes 3 AHB clocks cycles + 3 I2C master clock
* cycles. So retry once after a 1uS delay.
*/
do {
state = readl(qup->base + QUP_STATE);
if (state & QUP_STATE_VALID &&
(state & req_mask) == req_state)
return 0;
udelay(1);
} while (retries--);
return -ETIMEDOUT;
}
static int qup_i2c_poll_state(struct qup_i2c_dev *qup, u32 req_state)
{
return qup_i2c_poll_state_mask(qup, req_state, QUP_STATE_MASK);
}
static void qup_i2c_flush(struct qup_i2c_dev *qup)
{
u32 val = readl(qup->base + QUP_STATE);
val |= QUP_I2C_FLUSH;
writel(val, qup->base + QUP_STATE);
}
static int qup_i2c_poll_state_valid(struct qup_i2c_dev *qup)
{
return qup_i2c_poll_state_mask(qup, 0, 0);
}
static int qup_i2c_poll_state_i2c_master(struct qup_i2c_dev *qup)
{
return qup_i2c_poll_state_mask(qup, QUP_I2C_MAST_GEN, QUP_I2C_MAST_GEN);
}
static int qup_i2c_change_state(struct qup_i2c_dev *qup, u32 state)
{
if (qup_i2c_poll_state_valid(qup) != 0)
return -EIO;
writel(state, qup->base + QUP_STATE);
if (qup_i2c_poll_state(qup, state) != 0)
return -EIO;
return 0;
}
/* Check if I2C bus returns to IDLE state */
static int qup_i2c_bus_active(struct qup_i2c_dev *qup, int len)
{
unsigned long timeout;
u32 status;
int ret = 0;
timeout = jiffies + len * 4;
for (;;) {
status = readl(qup->base + QUP_I2C_STATUS);
if (!(status & I2C_STATUS_BUS_ACTIVE))
break;
if (time_after(jiffies, timeout))
ret = -ETIMEDOUT;
usleep_range(len, len * 2);
}
return ret;
}
static void qup_i2c_write_tx_fifo_v1(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
struct i2c_msg *msg = qup->msg;
u32 addr = i2c_8bit_addr_from_msg(msg);
u32 qup_tag;
int idx;
u32 val;
if (qup->pos == 0) {
val = QUP_TAG_START | addr;
idx = 1;
blk->tx_fifo_free--;
} else {
val = 0;
idx = 0;
}
while (blk->tx_fifo_free && qup->pos < msg->len) {
if (qup->pos == msg->len - 1)
qup_tag = QUP_TAG_STOP;
else
qup_tag = QUP_TAG_DATA;
if (idx & 1)
val |= (qup_tag | msg->buf[qup->pos]) << QUP_MSW_SHIFT;
else
val = qup_tag | msg->buf[qup->pos];
/* Write out the pair and the last odd value */
if (idx & 1 || qup->pos == msg->len - 1)
writel(val, qup->base + QUP_OUT_FIFO_BASE);
qup->pos++;
idx++;
blk->tx_fifo_free--;
}
}
static void qup_i2c_set_blk_data(struct qup_i2c_dev *qup,
struct i2c_msg *msg)
{
qup->blk.pos = 0;
qup->blk.data_len = msg->len;
qup->blk.count = DIV_ROUND_UP(msg->len, qup->blk_xfer_limit);
}
static int qup_i2c_get_data_len(struct qup_i2c_dev *qup)
{
int data_len;
if (qup->blk.data_len > qup->blk_xfer_limit)
data_len = qup->blk_xfer_limit;
else
data_len = qup->blk.data_len;
return data_len;
}
static bool qup_i2c_check_msg_len(struct i2c_msg *msg)
{
return ((msg->flags & I2C_M_RD) && (msg->flags & I2C_M_RECV_LEN));
}
static int qup_i2c_set_tags_smb(u16 addr, u8 *tags, struct qup_i2c_dev *qup,
struct i2c_msg *msg)
{
int len = 0;
if (qup->is_smbus_read) {
tags[len++] = QUP_TAG_V2_DATARD_STOP;
tags[len++] = qup_i2c_get_data_len(qup);
} else {
tags[len++] = QUP_TAG_V2_START;
tags[len++] = addr & 0xff;
if (msg->flags & I2C_M_TEN)
tags[len++] = addr >> 8;
tags[len++] = QUP_TAG_V2_DATARD;
/* Read 1 byte indicating the length of the SMBus message */
tags[len++] = 1;
}
return len;
}
static int qup_i2c_set_tags(u8 *tags, struct qup_i2c_dev *qup,
struct i2c_msg *msg)
{
u16 addr = i2c_8bit_addr_from_msg(msg);
int len = 0;
int data_len;
int last = (qup->blk.pos == (qup->blk.count - 1)) && (qup->is_last);
/* Handle tags for SMBus block read */
if (qup_i2c_check_msg_len(msg))
return qup_i2c_set_tags_smb(addr, tags, qup, msg);
if (qup->blk.pos == 0) {
tags[len++] = QUP_TAG_V2_START;
tags[len++] = addr & 0xff;
if (msg->flags & I2C_M_TEN)
tags[len++] = addr >> 8;
}
/* Send _STOP commands for the last block */
if (last) {
if (msg->flags & I2C_M_RD)
tags[len++] = QUP_TAG_V2_DATARD_STOP;
else
tags[len++] = QUP_TAG_V2_DATAWR_STOP;
} else {
if (msg->flags & I2C_M_RD)
tags[len++] = qup->blk.pos == (qup->blk.count - 1) ?
QUP_TAG_V2_DATARD_NACK :
QUP_TAG_V2_DATARD;
else
tags[len++] = QUP_TAG_V2_DATAWR;
}
data_len = qup_i2c_get_data_len(qup);
/* 0 implies 256 bytes */
if (data_len == QUP_READ_LIMIT)
tags[len++] = 0;
else
tags[len++] = data_len;
return len;
}
static void qup_i2c_bam_cb(void *data)
{
struct qup_i2c_dev *qup = data;
complete(&qup->xfer);
}
static int qup_sg_set_buf(struct scatterlist *sg, void *buf,
unsigned int buflen, struct qup_i2c_dev *qup,
int dir)
{
int ret;
sg_set_buf(sg, buf, buflen);
ret = dma_map_sg(qup->dev, sg, 1, dir);
if (!ret)
return -EINVAL;
return 0;
}
static void qup_i2c_rel_dma(struct qup_i2c_dev *qup)
{
if (qup->btx.dma)
dma_release_channel(qup->btx.dma);
if (qup->brx.dma)
dma_release_channel(qup->brx.dma);
qup->btx.dma = NULL;
qup->brx.dma = NULL;
}
static int qup_i2c_req_dma(struct qup_i2c_dev *qup)
{
int err;
if (!qup->btx.dma) {
qup->btx.dma = dma_request_chan(qup->dev, "tx");
if (IS_ERR(qup->btx.dma)) {
err = PTR_ERR(qup->btx.dma);
qup->btx.dma = NULL;
dev_err(qup->dev, "\n tx channel not available");
return err;
}
}
if (!qup->brx.dma) {
qup->brx.dma = dma_request_chan(qup->dev, "rx");
if (IS_ERR(qup->brx.dma)) {
dev_err(qup->dev, "\n rx channel not available");
err = PTR_ERR(qup->brx.dma);
qup->brx.dma = NULL;
qup_i2c_rel_dma(qup);
return err;
}
}
return 0;
}
static int qup_i2c_bam_make_desc(struct qup_i2c_dev *qup, struct i2c_msg *msg)
{
int ret = 0, limit = QUP_READ_LIMIT;
u32 len = 0, blocks, rem;
u32 i = 0, tlen, tx_len = 0;
u8 *tags;
qup->blk_xfer_limit = QUP_READ_LIMIT;
qup_i2c_set_blk_data(qup, msg);
blocks = qup->blk.count;
rem = msg->len - (blocks - 1) * limit;
if (msg->flags & I2C_M_RD) {
while (qup->blk.pos < blocks) {
tlen = (i == (blocks - 1)) ? rem : limit;
tags = &qup->start_tag.start[qup->tag_buf_pos + len];
len += qup_i2c_set_tags(tags, qup, msg);
qup->blk.data_len -= tlen;
/* scratch buf to read the start and len tags */
ret = qup_sg_set_buf(&qup->brx.sg[qup->brx.sg_cnt++],
&qup->brx.tag.start[0],
2, qup, DMA_FROM_DEVICE);
if (ret)
return ret;
ret = qup_sg_set_buf(&qup->brx.sg[qup->brx.sg_cnt++],
&msg->buf[limit * i],
tlen, qup,
DMA_FROM_DEVICE);
if (ret)
return ret;
i++;
qup->blk.pos = i;
}
ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++],
&qup->start_tag.start[qup->tag_buf_pos],
len, qup, DMA_TO_DEVICE);
if (ret)
return ret;
qup->tag_buf_pos += len;
} else {
while (qup->blk.pos < blocks) {
tlen = (i == (blocks - 1)) ? rem : limit;
tags = &qup->start_tag.start[qup->tag_buf_pos + tx_len];
len = qup_i2c_set_tags(tags, qup, msg);
qup->blk.data_len -= tlen;
ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++],
tags, len,
qup, DMA_TO_DEVICE);
if (ret)
return ret;
tx_len += len;
ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++],
&msg->buf[limit * i],
tlen, qup, DMA_TO_DEVICE);
if (ret)
return ret;
i++;
qup->blk.pos = i;
}
qup->tag_buf_pos += tx_len;
}
return 0;
}
static int qup_i2c_bam_schedule_desc(struct qup_i2c_dev *qup)
{
struct dma_async_tx_descriptor *txd, *rxd = NULL;
int ret = 0;
dma_cookie_t cookie_rx, cookie_tx;
u32 len = 0;
u32 tx_cnt = qup->btx.sg_cnt, rx_cnt = qup->brx.sg_cnt;
/* schedule the EOT and FLUSH I2C tags */
len = 1;
if (rx_cnt) {
qup->btx.tag.start[0] = QUP_BAM_INPUT_EOT;
len++;
/* scratch buf to read the BAM EOT FLUSH tags */
ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++],
&qup->brx.tag.start[0],
1, qup, DMA_FROM_DEVICE);
if (ret)
return ret;
}
qup->btx.tag.start[len - 1] = QUP_BAM_FLUSH_STOP;
ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++], &qup->btx.tag.start[0],
len, qup, DMA_TO_DEVICE);
if (ret)
return ret;
txd = dmaengine_prep_slave_sg(qup->btx.dma, qup->btx.sg, tx_cnt,
DMA_MEM_TO_DEV,
DMA_PREP_INTERRUPT | DMA_PREP_FENCE);
if (!txd) {
dev_err(qup->dev, "failed to get tx desc\n");
ret = -EINVAL;
goto desc_err;
}
if (!rx_cnt) {
txd->callback = qup_i2c_bam_cb;
txd->callback_param = qup;
}
cookie_tx = dmaengine_submit(txd);
if (dma_submit_error(cookie_tx)) {
ret = -EINVAL;
goto desc_err;
}
dma_async_issue_pending(qup->btx.dma);
if (rx_cnt) {
rxd = dmaengine_prep_slave_sg(qup->brx.dma, qup->brx.sg,
rx_cnt, DMA_DEV_TO_MEM,
DMA_PREP_INTERRUPT);
if (!rxd) {
dev_err(qup->dev, "failed to get rx desc\n");
ret = -EINVAL;
/* abort TX descriptors */
dmaengine_terminate_sync(qup->btx.dma);
goto desc_err;
}
rxd->callback = qup_i2c_bam_cb;
rxd->callback_param = qup;
cookie_rx = dmaengine_submit(rxd);
if (dma_submit_error(cookie_rx)) {
ret = -EINVAL;
goto desc_err;
}
dma_async_issue_pending(qup->brx.dma);
}
if (!wait_for_completion_timeout(&qup->xfer, qup->xfer_timeout)) {
dev_err(qup->dev, "normal trans timed out\n");
ret = -ETIMEDOUT;
}
if (ret || qup->bus_err || qup->qup_err) {
reinit_completion(&qup->xfer);
ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
if (ret) {
dev_err(qup->dev, "change to run state timed out");
goto desc_err;
}
qup_i2c_flush(qup);
/* wait for remaining interrupts to occur */
if (!wait_for_completion_timeout(&qup->xfer, HZ))
dev_err(qup->dev, "flush timed out\n");
ret = (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO;
}
desc_err:
dma_unmap_sg(qup->dev, qup->btx.sg, tx_cnt, DMA_TO_DEVICE);
if (rx_cnt)
dma_unmap_sg(qup->dev, qup->brx.sg, rx_cnt,
DMA_FROM_DEVICE);
return ret;
}
static void qup_i2c_bam_clear_tag_buffers(struct qup_i2c_dev *qup)
{
qup->btx.sg_cnt = 0;
qup->brx.sg_cnt = 0;
qup->tag_buf_pos = 0;
}
static int qup_i2c_bam_xfer(struct i2c_adapter *adap, struct i2c_msg *msg,
int num)
{
struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
int ret = 0;
int idx = 0;
enable_irq(qup->irq);
ret = qup_i2c_req_dma(qup);
if (ret)
goto out;
writel(0, qup->base + QUP_MX_INPUT_CNT);
writel(0, qup->base + QUP_MX_OUTPUT_CNT);
/* set BAM mode */
writel(QUP_REPACK_EN | QUP_BAM_MODE, qup->base + QUP_IO_MODE);
/* mask fifo irqs */
writel((0x3 << 8), qup->base + QUP_OPERATIONAL_MASK);
/* set RUN STATE */
ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
if (ret)
goto out;
writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
qup_i2c_bam_clear_tag_buffers(qup);
for (idx = 0; idx < num; idx++) {
qup->msg = msg + idx;
qup->is_last = idx == (num - 1);
ret = qup_i2c_bam_make_desc(qup, qup->msg);
if (ret)
break;
/*
* Make DMA descriptor and schedule the BAM transfer if its
* already crossed the maximum length. Since the memory for all
* tags buffers have been taken for 2 maximum possible
* transfers length so it will never cross the buffer actual
* length.
*/
if (qup->btx.sg_cnt > qup->max_xfer_sg_len ||
qup->brx.sg_cnt > qup->max_xfer_sg_len ||
qup->is_last) {
ret = qup_i2c_bam_schedule_desc(qup);
if (ret)
break;
qup_i2c_bam_clear_tag_buffers(qup);
}
}
out:
disable_irq(qup->irq);
qup->msg = NULL;
return ret;
}
static int qup_i2c_wait_for_complete(struct qup_i2c_dev *qup,
struct i2c_msg *msg)
{
unsigned long left;
int ret = 0;
left = wait_for_completion_timeout(&qup->xfer, qup->xfer_timeout);
if (!left) {
writel(1, qup->base + QUP_SW_RESET);
ret = -ETIMEDOUT;
}
if (qup->bus_err || qup->qup_err)
ret = (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO;
return ret;
}
static void qup_i2c_read_rx_fifo_v1(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
struct i2c_msg *msg = qup->msg;
u32 val = 0;
int idx = 0;
while (blk->fifo_available && qup->pos < msg->len) {
if ((idx & 1) == 0) {
/* Reading 2 words at time */
val = readl(qup->base + QUP_IN_FIFO_BASE);
msg->buf[qup->pos++] = val & 0xFF;
} else {
msg->buf[qup->pos++] = val >> QUP_MSW_SHIFT;
}
idx++;
blk->fifo_available--;
}
if (qup->pos == msg->len)
blk->rx_bytes_read = true;
}
static void qup_i2c_write_rx_tags_v1(struct qup_i2c_dev *qup)
{
struct i2c_msg *msg = qup->msg;
u32 addr, len, val;
addr = i2c_8bit_addr_from_msg(msg);
/* 0 is used to specify a length 256 (QUP_READ_LIMIT) */
len = (msg->len == QUP_READ_LIMIT) ? 0 : msg->len;
val = ((QUP_TAG_REC | len) << QUP_MSW_SHIFT) | QUP_TAG_START | addr;
writel(val, qup->base + QUP_OUT_FIFO_BASE);
}
static void qup_i2c_conf_v1(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
u32 qup_config = I2C_MINI_CORE | I2C_N_VAL;
u32 io_mode = QUP_REPACK_EN;
blk->is_tx_blk_mode = blk->total_tx_len > qup->out_fifo_sz;
blk->is_rx_blk_mode = blk->total_rx_len > qup->in_fifo_sz;
if (blk->is_tx_blk_mode) {
io_mode |= QUP_OUTPUT_BLK_MODE;
writel(0, qup->base + QUP_MX_WRITE_CNT);
writel(blk->total_tx_len, qup->base + QUP_MX_OUTPUT_CNT);
} else {
writel(0, qup->base + QUP_MX_OUTPUT_CNT);
writel(blk->total_tx_len, qup->base + QUP_MX_WRITE_CNT);
}
if (blk->total_rx_len) {
if (blk->is_rx_blk_mode) {
io_mode |= QUP_INPUT_BLK_MODE;
writel(0, qup->base + QUP_MX_READ_CNT);
writel(blk->total_rx_len, qup->base + QUP_MX_INPUT_CNT);
} else {
writel(0, qup->base + QUP_MX_INPUT_CNT);
writel(blk->total_rx_len, qup->base + QUP_MX_READ_CNT);
}
} else {
qup_config |= QUP_NO_INPUT;
}
writel(qup_config, qup->base + QUP_CONFIG);
writel(io_mode, qup->base + QUP_IO_MODE);
}
static void qup_i2c_clear_blk_v1(struct qup_i2c_block *blk)
{
blk->tx_fifo_free = 0;
blk->fifo_available = 0;
blk->rx_bytes_read = false;
}
static int qup_i2c_conf_xfer_v1(struct qup_i2c_dev *qup, bool is_rx)
{
struct qup_i2c_block *blk = &qup->blk;
int ret;
qup_i2c_clear_blk_v1(blk);
qup_i2c_conf_v1(qup);
ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
if (ret)
return ret;
writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
if (ret)
return ret;
reinit_completion(&qup->xfer);
enable_irq(qup->irq);
if (!blk->is_tx_blk_mode) {
blk->tx_fifo_free = qup->out_fifo_sz;
if (is_rx)
qup_i2c_write_rx_tags_v1(qup);
else
qup_i2c_write_tx_fifo_v1(qup);
}
ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
if (ret)
goto err;
ret = qup_i2c_wait_for_complete(qup, qup->msg);
if (ret)
goto err;
ret = qup_i2c_bus_active(qup, ONE_BYTE);
err:
disable_irq(qup->irq);
return ret;
}
static int qup_i2c_write_one(struct qup_i2c_dev *qup)
{
struct i2c_msg *msg = qup->msg;
struct qup_i2c_block *blk = &qup->blk;
qup->pos = 0;
blk->total_tx_len = msg->len + 1;
blk->total_rx_len = 0;
return qup_i2c_conf_xfer_v1(qup, false);
}
static int qup_i2c_read_one(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
qup->pos = 0;
blk->total_tx_len = 2;
blk->total_rx_len = qup->msg->len;
return qup_i2c_conf_xfer_v1(qup, true);
}
static int qup_i2c_xfer(struct i2c_adapter *adap,
struct i2c_msg msgs[],
int num)
{
struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
int ret, idx;
ret = pm_runtime_get_sync(qup->dev);
if (ret < 0)
goto out;
qup->bus_err = 0;
qup->qup_err = 0;
writel(1, qup->base + QUP_SW_RESET);
ret = qup_i2c_poll_state(qup, QUP_RESET_STATE);
if (ret)
goto out;
/* Configure QUP as I2C mini core */
writel(I2C_MINI_CORE | I2C_N_VAL, qup->base + QUP_CONFIG);
for (idx = 0; idx < num; idx++) {
if (qup_i2c_poll_state_i2c_master(qup)) {
ret = -EIO;
goto out;
}
if (qup_i2c_check_msg_len(&msgs[idx])) {
ret = -EINVAL;
goto out;
}
qup->msg = &msgs[idx];
if (msgs[idx].flags & I2C_M_RD)
ret = qup_i2c_read_one(qup);
else
ret = qup_i2c_write_one(qup);
if (ret)
break;
ret = qup_i2c_change_state(qup, QUP_RESET_STATE);
if (ret)
break;
}
if (ret == 0)
ret = num;
out:
pm_runtime_mark_last_busy(qup->dev);
pm_runtime_put_autosuspend(qup->dev);
return ret;
}
/*
* Configure registers related with reconfiguration during run and call it
* before each i2c sub transfer.
*/
static void qup_i2c_conf_count_v2(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
u32 qup_config = I2C_MINI_CORE | I2C_N_VAL_V2;
if (blk->is_tx_blk_mode)
writel(qup->config_run | blk->total_tx_len,
qup->base + QUP_MX_OUTPUT_CNT);
else
writel(qup->config_run | blk->total_tx_len,
qup->base + QUP_MX_WRITE_CNT);
if (blk->total_rx_len) {
if (blk->is_rx_blk_mode)
writel(qup->config_run | blk->total_rx_len,
qup->base + QUP_MX_INPUT_CNT);
else
writel(qup->config_run | blk->total_rx_len,
qup->base + QUP_MX_READ_CNT);
} else {
qup_config |= QUP_NO_INPUT;
}
writel(qup_config, qup->base + QUP_CONFIG);
}
/*
* Configure registers related with transfer mode (FIFO/Block)
* before starting of i2c transfer. It will be called only once in
* QUP RESET state.
*/
static void qup_i2c_conf_mode_v2(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
u32 io_mode = QUP_REPACK_EN;
if (blk->is_tx_blk_mode) {
io_mode |= QUP_OUTPUT_BLK_MODE;
writel(0, qup->base + QUP_MX_WRITE_CNT);
} else {
writel(0, qup->base + QUP_MX_OUTPUT_CNT);
}
if (blk->is_rx_blk_mode) {
io_mode |= QUP_INPUT_BLK_MODE;
writel(0, qup->base + QUP_MX_READ_CNT);
} else {
writel(0, qup->base + QUP_MX_INPUT_CNT);
}
writel(io_mode, qup->base + QUP_IO_MODE);
}
/* Clear required variables before starting of any QUP v2 sub transfer. */
static void qup_i2c_clear_blk_v2(struct qup_i2c_block *blk)
{
blk->send_last_word = false;
blk->tx_tags_sent = false;
blk->tx_fifo_data = 0;
blk->tx_fifo_data_pos = 0;
blk->tx_fifo_free = 0;
blk->rx_tags_fetched = false;
blk->rx_bytes_read = false;
blk->rx_fifo_data = 0;
blk->rx_fifo_data_pos = 0;
blk->fifo_available = 0;
}
/* Receive data from RX FIFO for read message in QUP v2 i2c transfer. */
static void qup_i2c_recv_data(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
int j;
for (j = blk->rx_fifo_data_pos;
blk->cur_blk_len && blk->fifo_available;
blk->cur_blk_len--, blk->fifo_available--) {
if (j == 0)
blk->rx_fifo_data = readl(qup->base + QUP_IN_FIFO_BASE);
*(blk->cur_data++) = blk->rx_fifo_data;
blk->rx_fifo_data >>= 8;
if (j == 3)
j = 0;
else
j++;
}
blk->rx_fifo_data_pos = j;
}
/* Receive tags for read message in QUP v2 i2c transfer. */
static void qup_i2c_recv_tags(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
blk->rx_fifo_data = readl(qup->base + QUP_IN_FIFO_BASE);
blk->rx_fifo_data >>= blk->rx_tag_len * 8;
blk->rx_fifo_data_pos = blk->rx_tag_len;
blk->fifo_available -= blk->rx_tag_len;
}
/*
* Read the data and tags from RX FIFO. Since in read case, the tags will be
* preceded by received data bytes so
* 1. Check if rx_tags_fetched is false i.e. the start of QUP block so receive
* all tag bytes and discard that.
* 2. Read the data from RX FIFO. When all the data bytes have been read then
* set rx_bytes_read to true.
*/
static void qup_i2c_read_rx_fifo_v2(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
if (!blk->rx_tags_fetched) {
qup_i2c_recv_tags(qup);
blk->rx_tags_fetched = true;
}
qup_i2c_recv_data(qup);
if (!blk->cur_blk_len)
blk->rx_bytes_read = true;
}
/*
* Write bytes in TX FIFO for write message in QUP v2 i2c transfer. QUP TX FIFO
* write works on word basis (4 bytes). Append new data byte write for TX FIFO
* in tx_fifo_data and write to TX FIFO when all the 4 bytes are present.
*/
static void
qup_i2c_write_blk_data(struct qup_i2c_dev *qup, u8 **data, unsigned int *len)
{
struct qup_i2c_block *blk = &qup->blk;
unsigned int j;
for (j = blk->tx_fifo_data_pos; *len && blk->tx_fifo_free;
(*len)--, blk->tx_fifo_free--) {
blk->tx_fifo_data |= *(*data)++ << (j * 8);
if (j == 3) {
writel(blk->tx_fifo_data,
qup->base + QUP_OUT_FIFO_BASE);
blk->tx_fifo_data = 0x0;
j = 0;
} else {
j++;
}
}
blk->tx_fifo_data_pos = j;
}
/* Transfer tags for read message in QUP v2 i2c transfer. */
static void qup_i2c_write_rx_tags_v2(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
qup_i2c_write_blk_data(qup, &blk->cur_tx_tags, &blk->tx_tag_len);
if (blk->tx_fifo_data_pos)
writel(blk->tx_fifo_data, qup->base + QUP_OUT_FIFO_BASE);
}
/*
* Write the data and tags in TX FIFO. Since in write case, both tags and data
* need to be written and QUP write tags can have maximum 256 data length, so
*
* 1. Check if tx_tags_sent is false i.e. the start of QUP block so write the
* tags to TX FIFO and set tx_tags_sent to true.
* 2. Check if send_last_word is true. It will be set when last few data bytes
* (less than 4 bytes) are remaining to be written in FIFO because of no FIFO
* space. All this data bytes are available in tx_fifo_data so write this
* in FIFO.
* 3. Write the data to TX FIFO and check for cur_blk_len. If it is non zero
* then more data is pending otherwise following 3 cases can be possible
* a. if tx_fifo_data_pos is zero i.e. all the data bytes in this block
* have been written in TX FIFO so nothing else is required.
* b. tx_fifo_free is non zero i.e tx FIFO is free so copy the remaining data
* from tx_fifo_data to tx FIFO. Since, qup_i2c_write_blk_data do write
* in 4 bytes and FIFO space is in multiple of 4 bytes so tx_fifo_free
* will be always greater than or equal to 4 bytes.
* c. tx_fifo_free is zero. In this case, last few bytes (less than 4
* bytes) are copied to tx_fifo_data but couldn't be sent because of
* FIFO full so make send_last_word true.
*/
static void qup_i2c_write_tx_fifo_v2(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
if (!blk->tx_tags_sent) {
qup_i2c_write_blk_data(qup, &blk->cur_tx_tags,
&blk->tx_tag_len);
blk->tx_tags_sent = true;
}
if (blk->send_last_word)
goto send_last_word;
qup_i2c_write_blk_data(qup, &blk->cur_data, &blk->cur_blk_len);
if (!blk->cur_blk_len) {
if (!blk->tx_fifo_data_pos)
return;
if (blk->tx_fifo_free)
goto send_last_word;
blk->send_last_word = true;
}
return;
send_last_word:
writel(blk->tx_fifo_data, qup->base + QUP_OUT_FIFO_BASE);
}
/*
* Main transfer function which read or write i2c data.
* The QUP v2 supports reconfiguration during run in which multiple i2c sub
* transfers can be scheduled.
*/
static int
qup_i2c_conf_xfer_v2(struct qup_i2c_dev *qup, bool is_rx, bool is_first,
bool change_pause_state)
{
struct qup_i2c_block *blk = &qup->blk;
struct i2c_msg *msg = qup->msg;
int ret;
/*
* Check if its SMBus Block read for which the top level read will be
* done into 2 QUP reads. One with message length 1 while other one is
* with actual length.
*/
if (qup_i2c_check_msg_len(msg)) {
if (qup->is_smbus_read) {
/*
* If the message length is already read in
* the first byte of the buffer, account for
* that by setting the offset
*/
blk->cur_data += 1;
is_first = false;
} else {
change_pause_state = false;
}
}
qup->config_run = is_first ? 0 : QUP_I2C_MX_CONFIG_DURING_RUN;
qup_i2c_clear_blk_v2(blk);
qup_i2c_conf_count_v2(qup);
/* If it is first sub transfer, then configure i2c bus clocks */
if (is_first) {
ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
if (ret)
return ret;
writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
if (ret)
return ret;
}
reinit_completion(&qup->xfer);
enable_irq(qup->irq);
/*
* In FIFO mode, tx FIFO can be written directly while in block mode the
* it will be written after getting OUT_BLOCK_WRITE_REQ interrupt
*/
if (!blk->is_tx_blk_mode) {
blk->tx_fifo_free = qup->out_fifo_sz;
if (is_rx)
qup_i2c_write_rx_tags_v2(qup);
else
qup_i2c_write_tx_fifo_v2(qup);
}
ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
if (ret)
goto err;
ret = qup_i2c_wait_for_complete(qup, msg);
if (ret)
goto err;
/* Move to pause state for all the transfers, except last one */
if (change_pause_state) {
ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
if (ret)
goto err;
}
err:
disable_irq(qup->irq);
return ret;
}
/*
* Transfer one read/write message in i2c transfer. It splits the message into
* multiple of blk_xfer_limit data length blocks and schedule each
* QUP block individually.
*/
static int qup_i2c_xfer_v2_msg(struct qup_i2c_dev *qup, int msg_id, bool is_rx)
{
int ret = 0;
unsigned int data_len, i;
struct i2c_msg *msg = qup->msg;
struct qup_i2c_block *blk = &qup->blk;
u8 *msg_buf = msg->buf;
qup->blk_xfer_limit = is_rx ? RECV_MAX_DATA_LEN : QUP_READ_LIMIT;
qup_i2c_set_blk_data(qup, msg);
for (i = 0; i < blk->count; i++) {
data_len = qup_i2c_get_data_len(qup);
blk->pos = i;
blk->cur_tx_tags = blk->tags;
blk->cur_blk_len = data_len;
blk->tx_tag_len =
qup_i2c_set_tags(blk->cur_tx_tags, qup, qup->msg);
blk->cur_data = msg_buf;
if (is_rx) {
blk->total_tx_len = blk->tx_tag_len;
blk->rx_tag_len = 2;
blk->total_rx_len = blk->rx_tag_len + data_len;
} else {
blk->total_tx_len = blk->tx_tag_len + data_len;
blk->total_rx_len = 0;
}
ret = qup_i2c_conf_xfer_v2(qup, is_rx, !msg_id && !i,
!qup->is_last || i < blk->count - 1);
if (ret)
return ret;
/* Handle SMBus block read length */
if (qup_i2c_check_msg_len(msg) && msg->len == 1 &&
!qup->is_smbus_read) {
if (msg->buf[0] > I2C_SMBUS_BLOCK_MAX)
return -EPROTO;
msg->len = msg->buf[0];
qup->is_smbus_read = true;
ret = qup_i2c_xfer_v2_msg(qup, msg_id, true);
qup->is_smbus_read = false;
if (ret)
return ret;
msg->len += 1;
}
msg_buf += data_len;
blk->data_len -= qup->blk_xfer_limit;
}
return ret;
}
/*
* QUP v2 supports 3 modes
* Programmed IO using FIFO mode : Less than FIFO size
* Programmed IO using Block mode : Greater than FIFO size
* DMA using BAM : Appropriate for any transaction size but the address should
* be DMA applicable
*
* This function determines the mode which will be used for this transfer. An
* i2c transfer contains multiple message. Following are the rules to determine
* the mode used.
* 1. Determine complete length, maximum tx and rx length for complete transfer.
* 2. If complete transfer length is greater than fifo size then use the DMA
* mode.
* 3. In FIFO or block mode, tx and rx can operate in different mode so check
* for maximum tx and rx length to determine mode.
*/
static int
qup_i2c_determine_mode_v2(struct qup_i2c_dev *qup,
struct i2c_msg msgs[], int num)
{
int idx;
bool no_dma = false;
unsigned int max_tx_len = 0, max_rx_len = 0, total_len = 0;
/* All i2c_msgs should be transferred using either dma or cpu */
for (idx = 0; idx < num; idx++) {
if (msgs[idx].flags & I2C_M_RD)
max_rx_len = max_t(unsigned int, max_rx_len,
msgs[idx].len);
else
max_tx_len = max_t(unsigned int, max_tx_len,
msgs[idx].len);
if (is_vmalloc_addr(msgs[idx].buf))
no_dma = true;
total_len += msgs[idx].len;
}
if (!no_dma && qup->is_dma &&
(total_len > qup->out_fifo_sz || total_len > qup->in_fifo_sz)) {
qup->use_dma = true;
} else {
qup->blk.is_tx_blk_mode = max_tx_len > qup->out_fifo_sz -
QUP_MAX_TAGS_LEN;
qup->blk.is_rx_blk_mode = max_rx_len > qup->in_fifo_sz -
READ_RX_TAGS_LEN;
}
return 0;
}
static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
struct i2c_msg msgs[],
int num)
{
struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
int ret, idx = 0;
qup->bus_err = 0;
qup->qup_err = 0;
ret = pm_runtime_get_sync(qup->dev);
if (ret < 0)
goto out;
ret = qup_i2c_determine_mode_v2(qup, msgs, num);
if (ret)
goto out;
writel(1, qup->base + QUP_SW_RESET);
ret = qup_i2c_poll_state(qup, QUP_RESET_STATE);
if (ret)
goto out;
/* Configure QUP as I2C mini core */
writel(I2C_MINI_CORE | I2C_N_VAL_V2, qup->base + QUP_CONFIG);
writel(QUP_V2_TAGS_EN, qup->base + QUP_I2C_MASTER_GEN);
if (qup_i2c_poll_state_i2c_master(qup)) {
ret = -EIO;
goto out;
}
if (qup->use_dma) {
reinit_completion(&qup->xfer);
ret = qup_i2c_bam_xfer(adap, &msgs[0], num);
qup->use_dma = false;
} else {
qup_i2c_conf_mode_v2(qup);
for (idx = 0; idx < num; idx++) {
qup->msg = &msgs[idx];
qup->is_last = idx == (num - 1);
ret = qup_i2c_xfer_v2_msg(qup, idx,
!!(msgs[idx].flags & I2C_M_RD));
if (ret)
break;
}
qup->msg = NULL;
}
if (!ret)
ret = qup_i2c_bus_active(qup, ONE_BYTE);
if (!ret)
qup_i2c_change_state(qup, QUP_RESET_STATE);
if (ret == 0)
ret = num;
out:
pm_runtime_mark_last_busy(qup->dev);
pm_runtime_put_autosuspend(qup->dev);
return ret;
}
static u32 qup_i2c_func(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL_ALL & ~I2C_FUNC_SMBUS_QUICK);
}
static const struct i2c_algorithm qup_i2c_algo = {
.master_xfer = qup_i2c_xfer,
.functionality = qup_i2c_func,
};
static const struct i2c_algorithm qup_i2c_algo_v2 = {
.master_xfer = qup_i2c_xfer_v2,
.functionality = qup_i2c_func,
};
/*
* The QUP block will issue a NACK and STOP on the bus when reaching
* the end of the read, the length of the read is specified as one byte
* which limits the possible read to 256 (QUP_READ_LIMIT) bytes.
*/
static const struct i2c_adapter_quirks qup_i2c_quirks = {
.flags = I2C_AQ_NO_ZERO_LEN,
.max_read_len = QUP_READ_LIMIT,
};
static const struct i2c_adapter_quirks qup_i2c_quirks_v2 = {
.flags = I2C_AQ_NO_ZERO_LEN,
};
static void qup_i2c_enable_clocks(struct qup_i2c_dev *qup)
{
clk_prepare_enable(qup->clk);
clk_prepare_enable(qup->pclk);
}
static void qup_i2c_disable_clocks(struct qup_i2c_dev *qup)
{
u32 config;
qup_i2c_change_state(qup, QUP_RESET_STATE);
clk_disable_unprepare(qup->clk);
config = readl(qup->base + QUP_CONFIG);
config |= QUP_CLOCK_AUTO_GATE;
writel(config, qup->base + QUP_CONFIG);
clk_disable_unprepare(qup->pclk);
}
static const struct acpi_device_id qup_i2c_acpi_match[] = {
{ "QCOM8010"},
{ },
};
MODULE_DEVICE_TABLE(acpi, qup_i2c_acpi_match);
static int qup_i2c_probe(struct platform_device *pdev)
{
static const int blk_sizes[] = {4, 16, 32};
struct qup_i2c_dev *qup;
unsigned long one_bit_t;
u32 io_mode, hw_ver, size;
int ret, fs_div, hs_div;
u32 src_clk_freq = DEFAULT_SRC_CLK;
u32 clk_freq = DEFAULT_CLK_FREQ;
int blocks;
bool is_qup_v1;
qup = devm_kzalloc(&pdev->dev, sizeof(*qup), GFP_KERNEL);
if (!qup)
return -ENOMEM;
qup->dev = &pdev->dev;
init_completion(&qup->xfer);
platform_set_drvdata(pdev, qup);
if (scl_freq) {
dev_notice(qup->dev, "Using override frequency of %u\n", scl_freq);
clk_freq = scl_freq;
} else {
ret = device_property_read_u32(qup->dev, "clock-frequency", &clk_freq);
if (ret) {
dev_notice(qup->dev, "using default clock-frequency %d",
DEFAULT_CLK_FREQ);
}
}
if (of_device_is_compatible(pdev->dev.of_node, "qcom,i2c-qup-v1.1.1")) {
qup->adap.algo = &qup_i2c_algo;
qup->adap.quirks = &qup_i2c_quirks;
is_qup_v1 = true;
} else {
qup->adap.algo = &qup_i2c_algo_v2;
qup->adap.quirks = &qup_i2c_quirks_v2;
is_qup_v1 = false;
if (acpi_match_device(qup_i2c_acpi_match, qup->dev))
goto nodma;
else
ret = qup_i2c_req_dma(qup);
if (ret == -EPROBE_DEFER)
goto fail_dma;
else if (ret != 0)
goto nodma;
qup->max_xfer_sg_len = (MX_BLOCKS << 1);
blocks = (MX_DMA_BLOCKS << 1) + 1;
qup->btx.sg = devm_kcalloc(&pdev->dev,
blocks, sizeof(*qup->btx.sg),
GFP_KERNEL);
if (!qup->btx.sg) {
ret = -ENOMEM;
goto fail_dma;
}
sg_init_table(qup->btx.sg, blocks);
qup->brx.sg = devm_kcalloc(&pdev->dev,
blocks, sizeof(*qup->brx.sg),
GFP_KERNEL);
if (!qup->brx.sg) {
ret = -ENOMEM;
goto fail_dma;
}
sg_init_table(qup->brx.sg, blocks);
/* 2 tag bytes for each block + 5 for start, stop tags */
size = blocks * 2 + 5;
qup->start_tag.start = devm_kzalloc(&pdev->dev,
size, GFP_KERNEL);
if (!qup->start_tag.start) {
ret = -ENOMEM;
goto fail_dma;
}
qup->brx.tag.start = devm_kzalloc(&pdev->dev, 2, GFP_KERNEL);
if (!qup->brx.tag.start) {
ret = -ENOMEM;
goto fail_dma;
}
qup->btx.tag.start = devm_kzalloc(&pdev->dev, 2, GFP_KERNEL);
if (!qup->btx.tag.start) {
ret = -ENOMEM;
goto fail_dma;
}
qup->is_dma = true;
}
nodma:
/* We support frequencies up to FAST Mode Plus (1MHz) */
if (!clk_freq || clk_freq > I2C_MAX_FAST_MODE_PLUS_FREQ) {
dev_err(qup->dev, "clock frequency not supported %d\n",
clk_freq);
return -EINVAL;
}
qup->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(qup->base))
return PTR_ERR(qup->base);
qup->irq = platform_get_irq(pdev, 0);
if (qup->irq < 0)
return qup->irq;
if (has_acpi_companion(qup->dev)) {
ret = device_property_read_u32(qup->dev,
"src-clock-hz", &src_clk_freq);
if (ret) {
dev_notice(qup->dev, "using default src-clock-hz %d",
DEFAULT_SRC_CLK);
}
ACPI_COMPANION_SET(&qup->adap.dev, ACPI_COMPANION(qup->dev));
} else {
qup->clk = devm_clk_get(qup->dev, "core");
if (IS_ERR(qup->clk)) {
dev_err(qup->dev, "Could not get core clock\n");
return PTR_ERR(qup->clk);
}
qup->pclk = devm_clk_get(qup->dev, "iface");
if (IS_ERR(qup->pclk)) {
dev_err(qup->dev, "Could not get iface clock\n");
return PTR_ERR(qup->pclk);
}
qup_i2c_enable_clocks(qup);
src_clk_freq = clk_get_rate(qup->clk);
}
/*
* Bootloaders might leave a pending interrupt on certain QUP's,
* so we reset the core before registering for interrupts.
*/
writel(1, qup->base + QUP_SW_RESET);
ret = qup_i2c_poll_state_valid(qup);
if (ret)
goto fail;
ret = devm_request_irq(qup->dev, qup->irq, qup_i2c_interrupt,
IRQF_TRIGGER_HIGH | IRQF_NO_AUTOEN,
"i2c_qup", qup);
if (ret) {
dev_err(qup->dev, "Request %d IRQ failed\n", qup->irq);
goto fail;
}
hw_ver = readl(qup->base + QUP_HW_VERSION);
dev_dbg(qup->dev, "Revision %x\n", hw_ver);
io_mode = readl(qup->base + QUP_IO_MODE);
/*
* The block/fifo size w.r.t. 'actual data' is 1/2 due to 'tag'
* associated with each byte written/received
*/
size = QUP_OUTPUT_BLOCK_SIZE(io_mode);
if (size >= ARRAY_SIZE(blk_sizes)) {
ret = -EIO;
goto fail;
}
qup->out_blk_sz = blk_sizes[size];
size = QUP_INPUT_BLOCK_SIZE(io_mode);
if (size >= ARRAY_SIZE(blk_sizes)) {
ret = -EIO;
goto fail;
}
qup->in_blk_sz = blk_sizes[size];
if (is_qup_v1) {
/*
* in QUP v1, QUP_CONFIG uses N as 15 i.e 16 bits constitutes a
* single transfer but the block size is in bytes so divide the
* in_blk_sz and out_blk_sz by 2
*/
qup->in_blk_sz /= 2;
qup->out_blk_sz /= 2;
qup->write_tx_fifo = qup_i2c_write_tx_fifo_v1;
qup->read_rx_fifo = qup_i2c_read_rx_fifo_v1;
qup->write_rx_tags = qup_i2c_write_rx_tags_v1;
} else {
qup->write_tx_fifo = qup_i2c_write_tx_fifo_v2;
qup->read_rx_fifo = qup_i2c_read_rx_fifo_v2;
qup->write_rx_tags = qup_i2c_write_rx_tags_v2;
}
size = QUP_OUTPUT_FIFO_SIZE(io_mode);
qup->out_fifo_sz = qup->out_blk_sz * (2 << size);
size = QUP_INPUT_FIFO_SIZE(io_mode);
qup->in_fifo_sz = qup->in_blk_sz * (2 << size);
hs_div = 3;
if (clk_freq <= I2C_MAX_STANDARD_MODE_FREQ) {
fs_div = ((src_clk_freq / clk_freq) / 2) - 3;
qup->clk_ctl = (hs_div << 8) | (fs_div & 0xff);
} else {
/* 33%/66% duty cycle */
fs_div = ((src_clk_freq / clk_freq) - 6) * 2 / 3;
qup->clk_ctl = ((fs_div / 2) << 16) | (hs_div << 8) | (fs_div & 0xff);
}
/*
* Time it takes for a byte to be clocked out on the bus.
* Each byte takes 9 clock cycles (8 bits + 1 ack).
*/
one_bit_t = (USEC_PER_SEC / clk_freq) + 1;
qup->one_byte_t = one_bit_t * 9;
qup->xfer_timeout = TOUT_MIN * HZ +
usecs_to_jiffies(MX_DMA_TX_RX_LEN * qup->one_byte_t);
dev_dbg(qup->dev, "IN:block:%d, fifo:%d, OUT:block:%d, fifo:%d\n",
qup->in_blk_sz, qup->in_fifo_sz,
qup->out_blk_sz, qup->out_fifo_sz);
i2c_set_adapdata(&qup->adap, qup);
qup->adap.dev.parent = qup->dev;
qup->adap.dev.of_node = pdev->dev.of_node;
qup->is_last = true;
strscpy(qup->adap.name, "QUP I2C adapter", sizeof(qup->adap.name));
pm_runtime_set_autosuspend_delay(qup->dev, MSEC_PER_SEC);
pm_runtime_use_autosuspend(qup->dev);
pm_runtime_set_active(qup->dev);
pm_runtime_enable(qup->dev);
ret = i2c_add_adapter(&qup->adap);
if (ret)
goto fail_runtime;
return 0;
fail_runtime:
pm_runtime_disable(qup->dev);
pm_runtime_set_suspended(qup->dev);
fail:
qup_i2c_disable_clocks(qup);
fail_dma:
if (qup->btx.dma)
dma_release_channel(qup->btx.dma);
if (qup->brx.dma)
dma_release_channel(qup->brx.dma);
return ret;
}
static int qup_i2c_remove(struct platform_device *pdev)
{
struct qup_i2c_dev *qup = platform_get_drvdata(pdev);
if (qup->is_dma) {
dma_release_channel(qup->btx.dma);
dma_release_channel(qup->brx.dma);
}
disable_irq(qup->irq);
qup_i2c_disable_clocks(qup);
i2c_del_adapter(&qup->adap);
pm_runtime_disable(qup->dev);
pm_runtime_set_suspended(qup->dev);
return 0;
}
#ifdef CONFIG_PM
static int qup_i2c_pm_suspend_runtime(struct device *device)
{
struct qup_i2c_dev *qup = dev_get_drvdata(device);
dev_dbg(device, "pm_runtime: suspending...\n");
qup_i2c_disable_clocks(qup);
return 0;
}
static int qup_i2c_pm_resume_runtime(struct device *device)
{
struct qup_i2c_dev *qup = dev_get_drvdata(device);
dev_dbg(device, "pm_runtime: resuming...\n");
qup_i2c_enable_clocks(qup);
return 0;
}
#endif
#ifdef CONFIG_PM_SLEEP
static int qup_i2c_suspend(struct device *device)
{
if (!pm_runtime_suspended(device))
return qup_i2c_pm_suspend_runtime(device);
return 0;
}
static int qup_i2c_resume(struct device *device)
{
qup_i2c_pm_resume_runtime(device);
pm_runtime_mark_last_busy(device);
pm_request_autosuspend(device);
return 0;
}
#endif
static const struct dev_pm_ops qup_i2c_qup_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(
qup_i2c_suspend,
qup_i2c_resume)
SET_RUNTIME_PM_OPS(
qup_i2c_pm_suspend_runtime,
qup_i2c_pm_resume_runtime,
NULL)
};
static const struct of_device_id qup_i2c_dt_match[] = {
{ .compatible = "qcom,i2c-qup-v1.1.1" },
{ .compatible = "qcom,i2c-qup-v2.1.1" },
{ .compatible = "qcom,i2c-qup-v2.2.1" },
{}
};
MODULE_DEVICE_TABLE(of, qup_i2c_dt_match);
static struct platform_driver qup_i2c_driver = {
.probe = qup_i2c_probe,
.remove = qup_i2c_remove,
.driver = {
.name = "i2c_qup",
.pm = &qup_i2c_qup_pm_ops,
.of_match_table = qup_i2c_dt_match,
.acpi_match_table = ACPI_PTR(qup_i2c_acpi_match),
},
};
module_platform_driver(qup_i2c_driver);
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:i2c_qup");