/* * Copyright (c) 2009-2013, 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 <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) /* I2C mini core related values */ #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_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) #define MX_TX_RX_LEN SZ_64K #define MX_BLOCKS (MX_TX_RX_LEN / QUP_READ_LIMIT) /* Max timeout in ms for 32k bytes */ #define TOUT_MAX 300 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_tag { u8 *start; dma_addr_t addr; }; struct qup_i2c_bam { struct qup_i2c_tag tag; struct dma_chan *dma; struct scatterlist *sg; }; 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; unsigned long one_byte_t; 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; /* To configure when bus is in run state */ int config_run; /* dma parameters */ bool is_dma; struct dma_pool *dpool; struct qup_i2c_tag start_tag; struct qup_i2c_bam brx; struct qup_i2c_bam btx; struct completion xfer; }; static irqreturn_t qup_i2c_interrupt(int irq, void *dev) { struct qup_i2c_dev *qup = dev; 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); /* Reset the QUP State in case of error */ if (qup_err || bus_err) { writel(QUP_RESET_STATE, qup->base + QUP_STATE); goto done; } if (opflags & QUP_IN_SVC_FLAG) writel(QUP_IN_SVC_FLAG, qup->base + QUP_OPERATIONAL); if (opflags & QUP_OUT_SVC_FLAG) writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL); 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; } /** * 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 void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg) { /* Number of entries to shift out, including the start */ int total = msg->len + 1; 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 int qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg *msg) { u32 addr = msg->addr << 1; u32 qup_tag; int idx; u32 val; int ret = 0; if (qup->pos == 0) { val = QUP_TAG_START | addr; idx = 1; } else { val = 0; idx = 0; } while (qup->pos < msg->len) { /* Check that there's space in the FIFO for our pair */ ret = check_for_fifo_space(qup); if (ret) return ret; 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++; } ret = qup_i2c_change_state(qup, QUP_RUN_STATE); return ret; } 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 = 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; } 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, int is_dma) { 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); 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_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; if ((msg->flags & I2C_M_RD) && last && is_dma) { tags[len++] = QUP_BAM_INPUT_EOT; tags[len++] = QUP_BAM_FLUSH_STOP; } 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, 0); 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) { 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_do_xfer(struct qup_i2c_dev *qup, struct i2c_msg *msg, int num) { struct dma_async_tx_descriptor *txd, *rxd = NULL; int ret = 0, idx = 0, limit = QUP_READ_LIMIT; dma_cookie_t cookie_rx, cookie_tx; u32 rx_nents = 0, tx_nents = 0, len, blocks, rem; u32 i, tlen, tx_len, tx_buf = 0, rx_buf = 0, off = 0; u8 *tags; while (idx < num) { tx_len = 0, len = 0, i = 0; qup->is_last = (idx == (num - 1)); qup_i2c_set_blk_data(qup, msg); blocks = qup->blk.count; rem = msg->len - (blocks - 1) * limit; if (msg->flags & I2C_M_RD) { rx_nents += (blocks * 2) + 1; tx_nents += 1; while (qup->blk.pos < blocks) { tlen = (i == (blocks - 1)) ? rem : limit; tags = &qup->start_tag.start[off + len]; len += qup_i2c_set_tags(tags, qup, msg, 1); qup->blk.data_len -= tlen; /* scratch buf to read the start and len tags */ ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++], &qup->brx.tag.start[0], 2, qup, DMA_FROM_DEVICE); if (ret) return ret; ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++], &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[tx_buf++], &qup->start_tag.start[off], len, qup, DMA_TO_DEVICE); if (ret) return ret; off += len; /* scratch buf to read the BAM EOT and FLUSH tags */ ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++], &qup->brx.tag.start[0], 2, qup, DMA_FROM_DEVICE); if (ret) return ret; } else { tx_nents += (blocks * 2); while (qup->blk.pos < blocks) { tlen = (i == (blocks - 1)) ? rem : limit; tags = &qup->start_tag.start[off + tx_len]; len = qup_i2c_set_tags(tags, qup, msg, 1); qup->blk.data_len -= tlen; ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++], tags, len, qup, DMA_TO_DEVICE); if (ret) return ret; tx_len += len; ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++], &msg->buf[limit * i], tlen, qup, DMA_TO_DEVICE); if (ret) return ret; i++; qup->blk.pos = i; } off += tx_len; if (idx == (num - 1)) { len = 1; if (rx_nents) { qup->btx.tag.start[0] = QUP_BAM_INPUT_EOT; len++; } 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; tx_nents += 1; } } idx++; msg++; } txd = dmaengine_prep_slave_sg(qup->btx.dma, qup->btx.sg, tx_nents, 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_nents) { 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_nents) { rxd = dmaengine_prep_slave_sg(qup->brx.dma, qup->brx.sg, rx_nents, 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, TOUT_MAX * HZ)) { dev_err(qup->dev, "normal trans timed out\n"); ret = -ETIMEDOUT; } if (ret || qup->bus_err || qup->qup_err) { if (qup_i2c_change_state(qup, QUP_RUN_STATE)) { dev_err(qup->dev, "change to run state timed out"); goto desc_err; } if (rx_nents) writel(QUP_BAM_INPUT_EOT, qup->base + QUP_OUT_FIFO_BASE); writel(QUP_BAM_FLUSH_STOP, qup->base + QUP_OUT_FIFO_BASE); 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"); qup_i2c_rel_dma(qup); ret = (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO; } desc_err: dma_unmap_sg(qup->dev, qup->btx.sg, tx_nents, DMA_TO_DEVICE); if (rx_nents) dma_unmap_sg(qup->dev, qup->brx.sg, rx_nents, DMA_FROM_DEVICE); return ret; } 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; 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->msg = msg; ret = qup_i2c_bam_do_xfer(qup, qup->msg, num); 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, HZ); 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 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; qup->pos = 0; enable_irq(qup->irq); qup_i2c_set_write_mode(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_change_state(qup, QUP_PAUSE_STATE); if (ret) goto err; ret = qup_i2c_issue_write(qup, msg); if (ret) goto err; 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; } while (qup->pos < msg->len); /* Wait for the outstanding data in the fifo to drain */ 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(struct qup_i2c_dev *qup, int 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); } 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); } } 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_issue_read(struct qup_i2c_dev *qup, struct i2c_msg *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 int qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg) { u32 val = 0; int idx; int ret = 0; for (idx = 0; qup->pos < msg->len; idx++) { if ((idx & 1) == 0) { /* Check that FIFO have data */ ret = qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY, SET_BIT, 4 * ONE_BYTE); if (ret) return ret; /* 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; } } 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) { 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); if (ret) goto err; writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL); ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE); if (ret) goto err; qup_i2c_issue_read(qup, msg); ret = qup_i2c_change_state(qup, QUP_RUN_STATE); if (ret) goto err; do { ret = qup_i2c_wait_for_complete(qup, msg); if (ret) goto err; ret = qup_i2c_read_fifo(qup, msg); if (ret) goto err; } while (qup->pos < msg->len); err: disable_irq(qup->irq); qup->msg = NULL; return ret; } 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; } if (msgs[idx].flags & I2C_M_RD) ret = qup_i2c_read_one(qup, &msgs[idx]); else ret = qup_i2c_write_one(qup, &msgs[idx]); 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; } 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, len, idx = 0, use_dma = 0; qup->bus_err = 0; qup->qup_err = 0; 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); 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; } len = (msgs[idx].len > qup->out_fifo_sz) || (msgs[idx].len > qup->in_fifo_sz); if ((!is_vmalloc_addr(msgs[idx].buf)) && len) { use_dma = 1; } else { use_dma = 0; break; } } } idx = 0; do { if (msgs[idx].len == 0) { ret = -EINVAL; goto out; } if (qup_i2c_poll_state_i2c_master(qup)) { ret = -EIO; goto out; } 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 (use_dma) { ret = qup_i2c_bam_xfer(adap, &msgs[idx], num); } 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)) && !use_dma && !ret); if (!ret) 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; int blocks; 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; } else { qup->adap.algo = &qup_i2c_algo_v2; ret = qup_i2c_req_dma(qup); if (ret == -EPROBE_DEFER) goto fail_dma; else if (ret != 0) goto nodma; blocks = (MX_BLOCKS << 1) + 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); } 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] / 2; 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; 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); 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; 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");