/* * Copyright (c) 2009-2013, 2016-2018, The Linux Foundation. All rights reserved. * Copyright (c) 2014, Sony Mobile Communications AB. * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 and * only version 2 as published by the Free Software Foundation. * * This program is distributed in the hope that 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. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* 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 #define QUP_TAG_V2_NOOP_PAD 0x97 /* 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) #define MX_TX_RX_LEN SZ_64K #define MX_BLOCKS (MX_TX_RX_LEN / QUP_READ_LIMIT) /* Min timeout for i2c transfers */ #define TOUT_MIN 2 /* 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 /* MAX_OUTPUT_DONE_FLAG has been received */ #define QUP_BLK_EVENT_TX_IRQ_DONE BIT(0) /* MAX_INPUT_DONE_FLAG has been received */ #define QUP_BLK_EVENT_RX_IRQ_DONE BIT(1) /* All the TX bytes have been written in TX FIFO */ #define QUP_BLK_EVENT_TX_DATA_DONE BIT(2) /* All the RX bytes have been read from RX FIFO */ #define QUP_BLK_EVENT_RX_DATA_DONE BIT(3) /* All the required events to mark a QUP I2C TX transfer completed */ #define QUP_BLK_EVENT_TX_DONE (QUP_BLK_EVENT_TX_IRQ_DONE | \ QUP_BLK_EVENT_TX_DATA_DONE) /* All the required events to mark a QUP I2C RX transfer completed */ #define QUP_BLK_EVENT_RX_DONE (QUP_BLK_EVENT_TX_DONE | \ QUP_BLK_EVENT_RX_IRQ_DONE | \ QUP_BLK_EVENT_RX_DATA_DONE) /* * 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_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 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 rd_limit; unsigned long one_byte_t; unsigned long xfer_timeout; struct qup_i2c_block blk; /* Current index in msg array */ int msg_id; 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; /* 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; /* Required events to mark QUP transfer as completed */ u32 blk_events; /* Already completed events in QUP transfer */ u32 cur_blk_events; /* The threshold length above which DMA will be used */ unsigned long dma_threshold; unsigned int max_xfer_sg_len; unsigned int tag_buf_pos; 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); /* * Ideally, would like to check QUP_MAX_OUTPUT_DONE_FLAG. * However, QUP_MAX_OUTPUT_DONE_FLAG is lagging behind * QUP_OUTPUT_SERVICE_FLAG. The only reason for * QUP_OUTPUT_SERVICE_FLAG to be set in FIFO mode is * QUP_MAX_OUTPUT_DONE_FLAG condition. The code checking * here QUP_OUTPUT_SERVICE_FLAG and assumes that * QUP_MAX_OUTPUT_DONE_FLAG. */ if (!blk->is_tx_blk_mode) qup->cur_blk_events |= QUP_BLK_EVENT_TX_IRQ_DONE; 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 (opflags & QUP_MX_OUTPUT_DONE) qup->cur_blk_events |= QUP_BLK_EVENT_TX_IRQ_DONE; if (opflags & QUP_MX_INPUT_DONE) qup->cur_blk_events |= QUP_BLK_EVENT_RX_IRQ_DONE; if (qup->cur_blk_events != qup->blk_events) 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; } static int qup_i2c_bus_active(struct qup_i2c_dev *qup, int len) { unsigned long timeout; u32 status; int ret = 0; if (qup->is_last) { 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_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->rd_limit); } static int qup_i2c_get_data_len(struct qup_i2c_dev *qup) { int data_len; if (qup->blk.data_len > qup->rd_limit) data_len = qup->rd_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; int last = (qup->blk.pos == (qup->blk.count - 1)) && (qup->is_last); 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_slave_channel_reason(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_slave_channel_reason(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->rd_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_buf = qup->btx.sg_cnt, rx_buf = qup->brx.sg_cnt; /* schedule the EOT and FLUSH I2C tags */ len = 1; if (rx_buf) { 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_buf++], &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_buf++], &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_buf, 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_buf) { 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_buf) { rxd = dmaengine_prep_slave_sg(qup->brx.dma, qup->brx.sg, rx_buf, 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_all(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); if (qup_i2c_change_state(qup, QUP_RUN_STATE)) { 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_buf, DMA_TO_DEVICE); if (rx_buf) dma_unmap_sg(qup->dev, qup->brx.sg, rx_buf, 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 transfer * lengths 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) { 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; } void qup_i2c_set_blk_event(struct qup_i2c_dev *qup, bool is_rx) { qup->cur_blk_events = 0; qup->blk_events = is_rx ? QUP_BLK_EVENT_RX_DONE : QUP_BLK_EVENT_TX_DONE; } 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 ? true : false; blk->is_rx_blk_mode = blk->total_rx_len > qup->in_fifo_sz ? true : false; 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); } void qup_i2c_clear_blk_v1(struct qup_i2c_block *blk) { blk->tx_fifo_free = 0; blk->fifo_available = 0; } 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 = msg->addr << 1; 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--; } if (qup->pos == msg->len) qup->cur_blk_events |= QUP_BLK_EVENT_TX_DATA_DONE; } 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) qup->cur_blk_events |= QUP_BLK_EVENT_RX_DATA_DONE; } static void qup_i2c_write_rx_tags_v1(struct qup_i2c_dev *qup) { struct i2c_msg *msg = qup->msg; u32 addr, len, val; addr = (msg->addr << 1) | 1; /* 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); qup->cur_blk_events |= QUP_BLK_EVENT_TX_DATA_DONE; } 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; qup_i2c_set_blk_event(qup, is_rx); 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); 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 (msgs[idx].len == 0) { ret = -EINVAL; goto out; } if (qup_i2c_poll_state_i2c_master(qup)) { ret = -EIO; 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; } /* * Function to configure registers related with reconfiguration during run * and will be done before each I2C sub transfer. */ 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); } /* * Function to configure registers related with transfer mode (FIFO/Block) * before starting of i2c transfer and will be done only once in QUP RESET * state. */ 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); } /* * Function to clear required variables before starting of any QUP v2 * sub transfer */ 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_fifo_data = 0; blk->rx_fifo_data_pos = 0; blk->fifo_available = 0; } /* * Function to receive data from RX FIFO for read message in QUP v2 * i2c transfer. */ 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; } /* Function to receive tags for read message in QUP v2 i2c transfer. */ 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; } /* * This function reads the data and tags from RX FIFO. Since in read case, the * tags will be preceded by received data bytes need to be written 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 * mark the QUP_BLK_EVENT_RX_DATA_DONE in current block event and return. */ 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) qup->cur_blk_events |= QUP_BLK_EVENT_RX_DATA_DONE; } /* * Function to write bytes in TX FIFO for write message in QUP v2 i2c * transfer. QUP TX FIFO write works on word basis (4 bytes). New byte write to * TX FIFO will be appended in this data tx_fifo_data and will be written to TX * FIFO when all the 4 bytes are available. */ 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; } /* Function to 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); qup->cur_blk_events |= QUP_BLK_EVENT_TX_DATA_DONE; } /* * This function writes 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 it follows simple internal state machine to manage it. * 1. Check if tx_tags_sent is false i.e. the start of QUP block so write the * tags to TX FIFO. * 2. Check if send_last_word is true. This 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 and mark the tx done. * 3. Write the data to TX FIFO and check for cur_blk_len. If this is non zero * then more data is pending otherwise following 3 cases can be possible * a. if tx_fifo_data_pos is zero that means all the data bytes in this block * have been written in TX FIFO so mark the tx done. * b. 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. * c. tx_fifo_free is non zero i.e tx FIFO is free so copy the remaining data * from tx_fifo_data to tx FIFO and mark the tx done. 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. */ 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) goto tx_data_done; 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); tx_data_done: qup->cur_blk_events |= QUP_BLK_EVENT_TX_DATA_DONE; } /* * Main transfer function which will be used for reading or writing 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; int ret; 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; } qup_i2c_set_blk_event(qup, is_rx); 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); 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; } /* * Function to transfer one read/write message in i2c transfer. It splits the * message into multiple of rd_limit data length blocks and schedule each QUP * block individually. */ static int qup_i2c_xfer_v2_msg(struct qup_i2c_dev *qup, 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->rd_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, !qup->msg_id && !i, !qup->is_last || i < blk->count - 1); if (ret) return ret; msg_buf += data_len; blk->data_len -= qup->rd_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 transactio 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 the tx and rx length including tags for each message and * maximum tx and rx length for complete transfer * 2. If tx or rx length is greater than DMA threshold than 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(struct qup_i2c_dev *qup, struct i2c_msg msgs[], int num) { unsigned long no_of_blk; bool no_dma = false; int idx = 0; unsigned long max_tx_len = 0, max_rx_len = 0; unsigned long cur_tx_len, cur_rx_len; unsigned long total_rx_len = 0, total_tx_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; cur_tx_len = 0; cur_rx_len = 0; /* for start and addr */ cur_tx_len += 2; if (msgs[idx].flags & I2C_M_TEN) cur_tx_len += 1; if (msgs[idx].flags & I2C_M_RD) { no_of_blk = DIV_ROUND_UP(msgs[idx].len, RECV_MAX_DATA_LEN); cur_rx_len += READ_RX_TAGS_LEN * no_of_blk; cur_rx_len += msgs[idx].len; } else { no_of_blk = DIV_ROUND_UP(msgs[idx].len, QUP_READ_LIMIT); cur_tx_len += msgs[idx].len; } cur_tx_len += 2 * no_of_blk; if (is_vmalloc_addr(msgs[idx].buf)) no_dma = true; max_tx_len = max(max_tx_len, cur_tx_len); max_rx_len = max(max_rx_len, cur_rx_len); total_rx_len += cur_rx_len; total_tx_len += cur_tx_len; } if (!no_dma && qup->is_dma && (total_tx_len > qup->dma_threshold || total_rx_len > qup->dma_threshold)) { qup->use_dma = true; } else { qup->blk.is_tx_blk_mode = max_tx_len > qup->out_fifo_sz ? true : false; qup->blk.is_rx_blk_mode = max_rx_len > qup->in_fifo_sz ? 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; 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(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_id = idx; qup->msg = &msgs[idx]; qup->is_last = idx == (num - 1); ret = qup_i2c_xfer_v2_msg(qup, !!(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 & ~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 struct i2c_adapter_quirks qup_i2c_quirks = { .max_read_len = QUP_READ_LIMIT, }; 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 int qup_i2c_probe(struct platform_device *pdev) { static const int blk_sizes[] = {4, 16, 32}; struct device_node *node = pdev->dev.of_node; struct qup_i2c_dev *qup; unsigned long one_bit_t; struct resource *res; u32 io_mode, hw_ver, size; int ret, fs_div, hs_div; int src_clk_freq; u32 clk_freq = 100000; u32 qup_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); 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; 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) goto fail_dma; else if (ret != 0) goto nodma; qup->max_xfer_sg_len = (MX_BLOCKS << 1); blocks = 2 * qup->max_xfer_sg_len + 1; qup->btx.sg = devm_kzalloc(&pdev->dev, sizeof(*qup->btx.sg) * blocks, GFP_KERNEL); if (!qup->btx.sg) { ret = -ENOMEM; goto fail_dma; } sg_init_table(qup->btx.sg, blocks); qup->brx.sg = devm_kzalloc(&pdev->dev, sizeof(*qup->brx.sg) * blocks, 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 (400KHz) */ if (!clk_freq || clk_freq > 400000) { dev_err(qup->dev, "clock frequency not supported %d\n", clk_freq); return -EINVAL; } res = platform_get_resource(pdev, IORESOURCE_MEM, 0); qup->base = devm_ioremap_resource(qup->dev, res); if (IS_ERR(qup->base)) return PTR_ERR(qup->base); qup->irq = platform_get_irq(pdev, 0); if (qup->irq < 0) { dev_err(qup->dev, "No IRQ defined\n"); return qup->irq; } 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); } if (!of_property_read_u32(node, "qup-clock-frequency", &qup_clk_freq)) { ret = clk_set_rate(qup->clk, qup_clk_freq); if (ret) { dev_err(qup->dev, "Set qup clock frequency failed\n"); goto fail; } } qup_i2c_enable_clocks(qup); /* * 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, "i2c_qup", qup); if (ret) { dev_err(qup->dev, "Request %d IRQ failed\n", qup->irq); goto fail; } disable_irq(qup->irq); 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); qup->dma_threshold = min_t(unsigned long, qup->out_fifo_sz, qup->in_fifo_sz); src_clk_freq = clk_get_rate(qup->clk); fs_div = ((src_clk_freq / clk_freq) / 2) - 3; hs_div = 3; qup->clk_ctl = (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(2 * MX_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; strlcpy(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, }, }; module_platform_driver(qup_i2c_driver); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("platform:i2c_qup");