summaryrefslogtreecommitdiffstats
path: root/drivers/i2c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-qup.c900
1 files changed, 515 insertions, 385 deletions
diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c
index 3bf3c349dc70..904dfec7ab96 100644
--- a/drivers/i2c/busses/i2c-qup.c
+++ b/drivers/i2c/busses/i2c-qup.c
@@ -141,17 +141,40 @@
#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
+
+/*
* 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
@@ -162,10 +185,20 @@ struct qup_i2c_block {
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;
@@ -198,6 +231,7 @@ struct qup_i2c_dev {
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;
@@ -212,10 +246,10 @@ struct qup_i2c_dev {
/* To check if this is the last msg */
bool is_last;
- bool is_qup_v1;
+ bool is_smbus_read;
/* To configure when bus is in run state */
- int config_run;
+ u32 config_run;
/* dma parameters */
bool is_dma;
@@ -223,6 +257,8 @@ struct qup_i2c_dev {
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;
@@ -287,9 +323,6 @@ static irqreturn_t qup_i2c_interrupt(int irq, void *dev)
goto done;
}
- if (!qup->is_qup_v1)
- goto done;
-
if (opflags & QUP_OUT_SVC_FLAG) {
writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL);
@@ -416,108 +449,6 @@ static int qup_i2c_bus_active(struct qup_i2c_dev *qup, int len)
return ret;
}
-/**
- * qup_i2c_wait_ready - wait for a give number of bytes in tx/rx path
- * @qup: The qup_i2c_dev device
- * @op: The bit/event to wait on
- * @val: value of the bit to wait on, 0 or 1
- * @len: The length the bytes to be transferred
- */
-static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val,
- int len)
-{
- unsigned long timeout;
- u32 opflags;
- u32 status;
- u32 shift = __ffs(op);
- int ret = 0;
-
- len *= qup->one_byte_t;
- /* timeout after a wait of twice the max time */
- timeout = jiffies + len * 4;
-
- for (;;) {
- opflags = readl(qup->base + QUP_OPERATIONAL);
- status = readl(qup->base + QUP_I2C_STATUS);
-
- if (((opflags & op) >> shift) == val) {
- if ((op == QUP_OUT_NOT_EMPTY) && qup->is_last) {
- if (!(status & I2C_STATUS_BUS_ACTIVE)) {
- ret = 0;
- goto done;
- }
- } else {
- ret = 0;
- goto done;
- }
- }
-
- if (time_after(jiffies, timeout)) {
- ret = -ETIMEDOUT;
- goto done;
- }
- usleep_range(len, len * 2);
- }
-
-done:
- if (qup->bus_err || qup->qup_err)
- ret = (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO;
-
- return ret;
-}
-
-static void qup_i2c_set_write_mode_v2(struct qup_i2c_dev *qup,
- struct i2c_msg *msg)
-{
- /* Number of entries to shift out, including the tags */
- int total = msg->len + qup->blk.tx_tag_len;
-
- total |= qup->config_run;
-
- if (total < qup->out_fifo_sz) {
- /* FIFO mode */
- writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
- writel(total, qup->base + QUP_MX_WRITE_CNT);
- } else {
- /* BLOCK mode (transfer data on chunks) */
- writel(QUP_OUTPUT_BLK_MODE | QUP_REPACK_EN,
- qup->base + QUP_IO_MODE);
- writel(total, qup->base + QUP_MX_OUTPUT_CNT);
- }
-}
-
-static int check_for_fifo_space(struct qup_i2c_dev *qup)
-{
- int ret;
-
- ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
- if (ret)
- goto out;
-
- ret = qup_i2c_wait_ready(qup, QUP_OUT_FULL,
- RESET_BIT, 4 * ONE_BYTE);
- if (ret) {
- /* Fifo is full. Drain out the fifo */
- ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
- if (ret)
- goto out;
-
- ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY,
- RESET_BIT, 256 * ONE_BYTE);
- if (ret) {
- dev_err(qup->dev, "timeout for fifo out full");
- goto out;
- }
-
- ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
- if (ret)
- goto out;
- }
-
-out:
- return ret;
-}
-
static void qup_i2c_write_tx_fifo_v1(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
@@ -560,60 +491,17 @@ static void qup_i2c_write_tx_fifo_v1(struct qup_i2c_dev *qup)
static void qup_i2c_set_blk_data(struct qup_i2c_dev *qup,
struct i2c_msg *msg)
{
- memset(&qup->blk, 0, sizeof(qup->blk));
-
+ qup->blk.pos = 0;
qup->blk.data_len = msg->len;
- qup->blk.count = (msg->len + QUP_READ_LIMIT - 1) / QUP_READ_LIMIT;
-
- /* 4 bytes for first block and 2 writes for rest */
- qup->blk.tx_tag_len = 4 + (qup->blk.count - 1) * 2;
-
- /* There are 2 tag bytes that are read in to fifo for every block */
- if (msg->flags & I2C_M_RD)
- qup->blk.rx_tag_len = qup->blk.count * 2;
-}
-
-static int qup_i2c_send_data(struct qup_i2c_dev *qup, int tlen, u8 *tbuf,
- int dlen, u8 *dbuf)
-{
- u32 val = 0, idx = 0, pos = 0, i = 0, t;
- int len = tlen + dlen;
- u8 *buf = tbuf;
- int ret = 0;
-
- while (len > 0) {
- ret = check_for_fifo_space(qup);
- if (ret)
- return ret;
-
- t = (len >= 4) ? 4 : len;
-
- while (idx < t) {
- if (!i && (pos >= tlen)) {
- buf = dbuf;
- pos = 0;
- i = 1;
- }
- val |= buf[pos++] << (idx++ * 8);
- }
-
- writel(val, qup->base + QUP_OUT_FIFO_BASE);
- idx = 0;
- val = 0;
- len -= 4;
- }
-
- ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
-
- return ret;
+ 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_READ_LIMIT)
- data_len = QUP_READ_LIMIT;
+ if (qup->blk.data_len > qup->blk_xfer_limit)
+ data_len = qup->blk_xfer_limit;
else
data_len = qup->blk.data_len;
@@ -630,9 +518,9 @@ static int qup_i2c_set_tags_smb(u16 addr, u8 *tags, struct qup_i2c_dev *qup,
{
int len = 0;
- if (msg->len > 1) {
+ if (qup->is_smbus_read) {
tags[len++] = QUP_TAG_V2_DATARD_STOP;
- tags[len++] = qup_i2c_get_data_len(qup) - 1;
+ tags[len++] = qup_i2c_get_data_len(qup);
} else {
tags[len++] = QUP_TAG_V2_START;
tags[len++] = addr & 0xff;
@@ -694,24 +582,6 @@ static int qup_i2c_set_tags(u8 *tags, struct qup_i2c_dev *qup,
return len;
}
-static int qup_i2c_issue_xfer_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg)
-{
- int data_len = 0, tag_len, index;
- int ret;
-
- tag_len = qup_i2c_set_tags(qup->blk.tags, qup, msg);
- index = msg->len - qup->blk.data_len;
-
- /* only tags are written for read */
- if (!(msg->flags & I2C_M_RD))
- data_len = qup_i2c_get_data_len(qup);
-
- ret = qup_i2c_send_data(qup, tag_len, qup->blk.tags,
- data_len, &msg->buf[index]);
- qup->blk.data_len -= data_len;
-
- return ret;
-}
static void qup_i2c_bam_cb(void *data)
{
@@ -778,6 +648,7 @@ static int qup_i2c_bam_make_desc(struct qup_i2c_dev *qup, struct i2c_msg *msg)
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;
@@ -1026,7 +897,7 @@ static int qup_i2c_wait_for_complete(struct qup_i2c_dev *qup,
unsigned long left;
int ret = 0;
- left = wait_for_completion_timeout(&qup->xfer, HZ);
+ left = wait_for_completion_timeout(&qup->xfer, qup->xfer_timeout);
if (!left) {
writel(1, qup->base + QUP_SW_RESET);
ret = -ETIMEDOUT;
@@ -1038,65 +909,6 @@ static int qup_i2c_wait_for_complete(struct qup_i2c_dev *qup,
return ret;
}
-static int qup_i2c_write_one_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg)
-{
- int ret = 0;
-
- qup->msg = msg;
- qup->pos = 0;
- enable_irq(qup->irq);
- qup_i2c_set_blk_data(qup, msg);
- qup_i2c_set_write_mode_v2(qup, msg);
-
- ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
- if (ret)
- goto err;
-
- writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
-
- do {
- ret = qup_i2c_issue_xfer_v2(qup, msg);
- if (ret)
- goto err;
-
- ret = qup_i2c_wait_for_complete(qup, msg);
- if (ret)
- goto err;
-
- qup->blk.pos++;
- } while (qup->blk.pos < qup->blk.count);
-
- ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, ONE_BYTE);
-
-err:
- disable_irq(qup->irq);
- qup->msg = NULL;
-
- return ret;
-}
-
-static void qup_i2c_set_read_mode_v2(struct qup_i2c_dev *qup, int len)
-{
- int tx_len = qup->blk.tx_tag_len;
-
- len += qup->blk.rx_tag_len;
- len |= qup->config_run;
- tx_len |= qup->config_run;
-
- if (len < qup->in_fifo_sz) {
- /* FIFO mode */
- writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
- writel(tx_len, qup->base + QUP_MX_WRITE_CNT);
- writel(len, qup->base + QUP_MX_READ_CNT);
- } else {
- /* BLOCK mode (transfer data on chunks) */
- writel(QUP_INPUT_BLK_MODE | QUP_REPACK_EN,
- qup->base + QUP_IO_MODE);
- writel(tx_len, qup->base + QUP_MX_OUTPUT_CNT);
- writel(len, qup->base + QUP_MX_INPUT_CNT);
- }
-}
-
static void qup_i2c_read_rx_fifo_v1(struct qup_i2c_dev *qup)
{
struct qup_i2c_block *blk = &qup->blk;
@@ -1120,104 +932,6 @@ static void qup_i2c_read_rx_fifo_v1(struct qup_i2c_dev *qup)
blk->rx_bytes_read = true;
}
-static int qup_i2c_read_fifo_v2(struct qup_i2c_dev *qup,
- struct i2c_msg *msg)
-{
- u32 val;
- int idx, pos = 0, ret = 0, total, msg_offset = 0;
-
- /*
- * If the message length is already read in
- * the first byte of the buffer, account for
- * that by setting the offset
- */
- if (qup_i2c_check_msg_len(msg) && (msg->len > 1))
- msg_offset = 1;
- total = qup_i2c_get_data_len(qup);
- total -= msg_offset;
-
- /* 2 extra bytes for read tags */
- while (pos < (total + 2)) {
- /* Check that FIFO have data */
- ret = qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY,
- SET_BIT, 4 * ONE_BYTE);
- if (ret) {
- dev_err(qup->dev, "timeout for fifo not empty");
- return ret;
- }
- val = readl(qup->base + QUP_IN_FIFO_BASE);
-
- for (idx = 0; idx < 4; idx++, val >>= 8, pos++) {
- /* first 2 bytes are tag bytes */
- if (pos < 2)
- continue;
-
- if (pos >= (total + 2))
- goto out;
- msg->buf[qup->pos + msg_offset] = val & 0xff;
- qup->pos++;
- }
- }
-
-out:
- qup->blk.data_len -= total;
-
- return ret;
-}
-
-static int qup_i2c_read_one_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg)
-{
- int ret = 0;
-
- qup->msg = msg;
- qup->pos = 0;
- enable_irq(qup->irq);
- qup_i2c_set_blk_data(qup, msg);
- qup_i2c_set_read_mode_v2(qup, msg->len);
-
- ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
- if (ret)
- goto err;
-
- writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
-
- do {
- ret = qup_i2c_issue_xfer_v2(qup, msg);
- if (ret)
- goto err;
-
- ret = qup_i2c_wait_for_complete(qup, msg);
- if (ret)
- goto err;
-
- ret = qup_i2c_read_fifo_v2(qup, msg);
- if (ret)
- goto err;
-
- qup->blk.pos++;
-
- /* Handle SMBus block read length */
- if (qup_i2c_check_msg_len(msg) && (msg->len == 1)) {
- if (msg->buf[0] > I2C_SMBUS_BLOCK_MAX) {
- ret = -EPROTO;
- goto err;
- }
- msg->len += msg->buf[0];
- qup->pos = 0;
- qup_i2c_set_blk_data(qup, msg);
- /* set tag length for block read */
- qup->blk.tx_tag_len = 2;
- qup_i2c_set_read_mode_v2(qup, msg->buf[0]);
- }
- } while (qup->blk.pos < qup->blk.count);
-
-err:
- disable_irq(qup->irq);
- qup->msg = NULL;
-
- return ret;
-}
-
static void qup_i2c_write_rx_tags_v1(struct qup_i2c_dev *qup)
{
struct i2c_msg *msg = qup->msg;
@@ -1404,13 +1118,434 @@ out:
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 reamining 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].len == 0)
+ return -EINVAL;
+
+ 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 ? true : false;
+ qup->blk.is_rx_blk_mode = max_rx_len > qup->in_fifo_sz -
+ READ_RX_TAGS_LEN ? true : false;
+ }
+
+ 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;
- unsigned int total_len = 0;
qup->bus_err = 0;
qup->qup_err = 0;
@@ -1419,6 +1554,10 @@ static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
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)
@@ -1428,60 +1567,35 @@ static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
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->is_dma)) {
- /* All i2c_msgs should be transferred using either dma or cpu */
- for (idx = 0; idx < num; idx++) {
- if (msgs[idx].len == 0) {
- ret = -EINVAL;
- goto out;
- }
-
- if (is_vmalloc_addr(msgs[idx].buf))
- break;
-
- total_len += msgs[idx].len;
- }
-
- if (idx == num && (total_len > qup->out_fifo_sz ||
- total_len > qup->in_fifo_sz))
- qup->use_dma = true;
+ if (qup_i2c_poll_state_i2c_master(qup)) {
+ ret = -EIO;
+ goto out;
}
- idx = 0;
+ 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);
- do {
- if (msgs[idx].len == 0) {
- ret = -EINVAL;
- goto out;
- }
+ for (idx = 0; idx < num; idx++) {
+ qup->msg = &msgs[idx];
+ qup->is_last = idx == (num - 1);
- if (qup_i2c_poll_state_i2c_master(qup)) {
- ret = -EIO;
- goto out;
+ ret = qup_i2c_xfer_v2_msg(qup, idx,
+ !!(msgs[idx].flags & I2C_M_RD));
+ if (ret)
+ break;
}
+ qup->msg = NULL;
+ }
- qup->is_last = (idx == (num - 1));
- if (idx)
- qup->config_run = QUP_I2C_MX_CONFIG_DURING_RUN;
- else
- qup->config_run = 0;
-
- reinit_completion(&qup->xfer);
-
- if (qup->use_dma) {
- ret = qup_i2c_bam_xfer(adap, &msgs[idx], num);
- qup->use_dma = false;
- break;
- } else {
- if (msgs[idx].flags & I2C_M_RD)
- ret = qup_i2c_read_one_v2(qup, &msgs[idx]);
- else
- ret = qup_i2c_write_one_v2(qup, &msgs[idx]);
- }
- } while ((idx++ < (num - 1)) && !ret);
+ if (!ret)
+ ret = qup_i2c_bus_active(qup, ONE_BYTE);
if (!ret)
- ret = qup_i2c_change_state(qup, QUP_RESET_STATE);
+ qup_i2c_change_state(qup, QUP_RESET_STATE);
if (ret == 0)
ret = num;
@@ -1545,6 +1659,7 @@ static int qup_i2c_probe(struct platform_device *pdev)
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)
@@ -1563,12 +1678,10 @@ static int qup_i2c_probe(struct platform_device *pdev)
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;
- qup->is_qup_v1 = true;
- 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;
+ is_qup_v1 = true;
} else {
qup->adap.algo = &qup_i2c_algo_v2;
+ is_qup_v1 = false;
ret = qup_i2c_req_dma(qup);
if (ret == -EPROBE_DEFER)
@@ -1694,14 +1807,31 @@ nodma:
ret = -EIO;
goto fail;
}
- qup->out_blk_sz = blk_sizes[size] / 2;
+ 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] / 2;
+ 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);