diff options
author | Sricharan R <sricharan@codeaurora.org> | 2016-01-19 10:02:42 (GMT) |
---|---|---|
committer | Wolfram Sang <wsa@the-dreams.de> | 2016-02-12 18:32:08 (GMT) |
commit | 191424bb6166f638aaf6f18387818e9e771e441b (patch) | |
tree | d2484e03f317b512a85692db886ab0cb818f8c61 /drivers/i2c | |
parent | c4f0c5fb383adb9e703d7de2bd45d3604e572528 (diff) | |
download | linux-191424bb6166f638aaf6f18387818e9e771e441b.tar.xz |
i2c: qup: Add V2 tags support
QUP from version 2.1.1 onwards, supports a new format of
i2c command tags. Tag codes instructs the controller to
perform a operation like read/write. This new tagging version
supports bam dma and transfers of more than 256 bytes without 'stop'
in between. Adding the support for the same.
For each block a data_write/read tag and data_len tag is added to
the output fifo. For the final block of data write_stop/read_stop
tag is used.
Signed-off-by: Andy Gross <andy.gross@linaro.org>
Signed-off-by: Sricharan R <sricharan@codeaurora.org>
Tested-by: Archit Taneja <architt@codeaurora.org>
Tested-by: Telkar Nagender <ntelkar@codeaurora.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
-rw-r--r-- | drivers/i2c/busses/i2c-qup.c | 415 |
1 files changed, 386 insertions, 29 deletions
diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c index 81ed120..715d4d7 100644 --- a/drivers/i2c/busses/i2c-qup.c +++ b/drivers/i2c/busses/i2c-qup.c @@ -42,6 +42,7 @@ #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 @@ -69,6 +70,8 @@ #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) @@ -79,6 +82,7 @@ #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) @@ -91,6 +95,13 @@ #define QUP_TAG_STOP (3 << 8) #define QUP_TAG_REC (4 << 8) +/* 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_STOP 0x87 + /* Status, Error flags */ #define I2C_STATUS_WR_BUFFER_FULL BIT(0) #define I2C_STATUS_BUS_ACTIVE BIT(8) @@ -102,6 +113,15 @@ #define RESET_BIT 0x0 #define ONE_BYTE 0x1 +struct qup_i2c_block { + int count; + int pos; + int tx_tag_len; + int rx_tag_len; + int data_len; + u8 tags[6]; +}; + struct qup_i2c_dev { struct device *dev; void __iomem *base; @@ -117,6 +137,7 @@ struct qup_i2c_dev { int in_blk_sz; unsigned long one_byte_t; + struct qup_i2c_block blk; struct i2c_msg *msg; /* Current posion in user message buffer */ @@ -263,6 +284,24 @@ static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val, } } +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; + + 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 void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) { /* Number of entries to shift out, including the start */ @@ -324,9 +363,189 @@ static int qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg *msg) return ret; } -static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) +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.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 = qup_i2c_wait_ready(qup, QUP_OUT_FULL, + RESET_BIT, 4 * ONE_BYTE); + if (ret) { + dev_err(qup->dev, "timeout for fifo out full"); + 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; + } + + return ret; +} + +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; + else + data_len = qup->blk.data_len; + + return data_len; +} + +static int qup_i2c_set_tags(u8 *tags, struct qup_i2c_dev *qup, + struct i2c_msg *msg) +{ + u16 addr = (msg->addr << 1) | ((msg->flags & I2C_M_RD) == I2C_M_RD); + int len = 0; + int data_len; + + 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 (qup->blk.pos == (qup->blk.count - 1)) { + 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_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 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 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, HZ); + if (!left) { + writel(1, qup->base + QUP_SW_RESET); + ret = -ETIMEDOUT; + } + + if (qup->bus_err || qup->qup_err) { + if (qup->bus_err & QUP_I2C_NACK_FLAG) { + dev_err(qup->dev, "NACK from %x\n", msg->addr); + ret = -EIO; + } + } + + 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 int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) +{ int ret; qup->msg = msg; @@ -355,19 +574,9 @@ static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) if (ret) goto err; - left = wait_for_completion_timeout(&qup->xfer, HZ); - if (!left) { - writel(1, qup->base + QUP_SW_RESET); - ret = -ETIMEDOUT; - goto err; - } - - if (qup->bus_err || qup->qup_err) { - if (qup->bus_err & QUP_I2C_NACK_FLAG) - dev_err(qup->dev, "NACK from %x\n", msg->addr); - ret = -EIO; + ret = qup_i2c_wait_for_complete(qup, msg); + if (ret) goto err; - } } while (qup->pos < msg->len); /* Wait for the outstanding data in the fifo to drain */ @@ -394,6 +603,26 @@ static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len) } } +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; + + if (len < qup->in_fifo_sz) { + /* FIFO mode */ + writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE); + writel(len, qup->base + QUP_MX_READ_CNT); + writel(tx_len, qup->base + QUP_MX_WRITE_CNT); + } else { + /* BLOCK mode (transfer data on chunks) */ + writel(QUP_INPUT_BLK_MODE | QUP_REPACK_EN, + qup->base + QUP_IO_MODE); + writel(len, qup->base + QUP_MX_INPUT_CNT); + writel(tx_len, qup->base + QUP_MX_OUTPUT_CNT); + } +} + static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg *msg) { u32 addr, len, val; @@ -434,16 +663,90 @@ static int qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg) return ret; } +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; + + total = qup_i2c_get_data_len(qup); + + /* 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++] = val & 0xff; + } + } + +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++; + } while (qup->blk.pos < qup->blk.count); + +err: + disable_irq(qup->irq); + qup->msg = NULL; + + return ret; +} + static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) { - unsigned long left; int ret; qup->msg = msg; qup->pos = 0; enable_irq(qup->irq); - qup_i2c_set_read_mode(qup, msg->len); ret = qup_i2c_change_state(qup, QUP_RUN_STATE); @@ -463,19 +766,9 @@ static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg) goto err; do { - left = wait_for_completion_timeout(&qup->xfer, HZ); - if (!left) { - writel(1, qup->base + QUP_SW_RESET); - ret = -ETIMEDOUT; + ret = qup_i2c_wait_for_complete(qup, msg); + if (ret) goto err; - } - - if (qup->bus_err || qup->qup_err) { - if (qup->bus_err & QUP_I2C_NACK_FLAG) - dev_err(qup->dev, "NACK from %x\n", msg->addr); - ret = -EIO; - goto err; - } ret = qup_i2c_read_fifo(qup, msg); if (ret) @@ -542,6 +835,60 @@ out: return ret; } +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; + + ret = pm_runtime_get_sync(qup->dev); + if (ret < 0) + 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); + + for (idx = 0; idx < num; idx++) { + if (msgs[idx].len == 0) { + ret = -EINVAL; + goto out; + } + + if (qup_i2c_poll_state_i2c_master(qup)) { + ret = -EIO; + goto out; + } + + reinit_completion(&qup->xfer); + + 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]); + + if (!ret) + 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; +} + static u32 qup_i2c_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); @@ -552,6 +899,11 @@ static const struct i2c_algorithm qup_i2c_algo = { .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 @@ -601,6 +953,13 @@ static int qup_i2c_probe(struct platform_device *pdev) of_property_read_u32(node, "clock-frequency", &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; + } else { + qup->adap.algo = &qup_i2c_algo_v2; + } + /* We support frequencies up to FAST Mode (400KHz) */ if (!clk_freq || clk_freq > 400000) { dev_err(qup->dev, "clock frequency not supported %d\n", @@ -696,8 +1055,6 @@ static int qup_i2c_probe(struct platform_device *pdev) qup->out_blk_sz, qup->out_fifo_sz); i2c_set_adapdata(&qup->adap, qup); - qup->adap.algo = &qup_i2c_algo; - qup->adap.quirks = &qup_i2c_quirks; qup->adap.dev.parent = qup->dev; qup->adap.dev.of_node = pdev->dev.of_node; strlcpy(qup->adap.name, "QUP I2C adapter", sizeof(qup->adap.name)); |