diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-imx.c')
-rw-r--r-- | drivers/i2c/busses/i2c-imx.c | 532 |
1 files changed, 451 insertions, 81 deletions
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index 3842e527116b..de01dfecb16e 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -17,7 +17,7 @@ * Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt> * * Copyright 2013 Freescale Semiconductor, Inc. - * Copyright 2020 NXP + * Copyright 2020, 2024 NXP * */ @@ -84,6 +84,7 @@ #define IMX_I2C_REGSHIFT 2 #define VF610_I2C_REGSHIFT 0 +#define S32G_I2C_REGSHIFT 0 /* Bits of IMX I2C registers */ #define I2SR_RXAK 0x01 @@ -165,9 +166,34 @@ static struct imx_i2c_clk_pair vf610_i2c_clk_div[] = { { 3840, 0x3F }, { 4096, 0x7B }, { 5120, 0x7D }, { 6144, 0x7E }, }; +/* S32G2/S32G3 clock divider, register value pairs */ +static struct imx_i2c_clk_pair s32g2_i2c_clk_div[] = { + { 34, 0x00 }, { 36, 0x01 }, { 38, 0x02 }, { 40, 0x03 }, + { 42, 0x04 }, { 44, 0x05 }, { 46, 0x06 }, { 48, 0x09 }, + { 52, 0x0A }, { 54, 0x07 }, { 56, 0x0B }, { 60, 0x0C }, + { 64, 0x0D }, { 68, 0x40 }, { 72, 0x0E }, { 76, 0x42 }, + { 80, 0x12 }, { 84, 0x0F }, { 88, 0x13 }, { 96, 0x14 }, + { 104, 0x15 }, { 108, 0x47 }, { 112, 0x19 }, { 120, 0x16 }, + { 128, 0x1A }, { 136, 0x80 }, { 144, 0x17 }, { 152, 0x82 }, + { 160, 0x1C }, { 168, 0x84 }, { 176, 0x1D }, { 192, 0x21 }, + { 208, 0x1E }, { 216, 0x87 }, { 224, 0x22 }, { 240, 0x56 }, + { 256, 0x1F }, { 288, 0x24 }, { 320, 0x25 }, { 336, 0x8F }, + { 352, 0x93 }, { 356, 0x5D }, { 358, 0x98 }, { 384, 0x26 }, + { 416, 0x56 }, { 448, 0x2A }, { 480, 0x27 }, { 512, 0x2B }, + { 576, 0x2C }, { 640, 0x2D }, { 704, 0x9D }, { 768, 0x2E }, + { 832, 0x9D }, { 896, 0x32 }, { 960, 0x2F }, { 1024, 0x33 }, + { 1152, 0x34 }, { 1280, 0x35 }, { 1536, 0x36 }, { 1792, 0x3A }, + { 1920, 0x37 }, { 2048, 0x3B }, { 2304, 0x74 }, { 2560, 0x3D }, + { 3072, 0x3E }, { 3584, 0x7A }, { 3840, 0x3F }, { 4096, 0x7B }, + { 4608, 0x7C }, { 5120, 0x7D }, { 6144, 0x7E }, { 7168, 0xBA }, + { 7680, 0x7F }, { 8192, 0xBB }, { 9216, 0xBC }, { 10240, 0xBD }, + { 12288, 0xBE }, { 15360, 0xBF }, +}; + enum imx_i2c_type { IMX1_I2C, IMX21_I2C, + S32G_I2C, VF610_I2C, }; @@ -197,6 +223,17 @@ struct imx_i2c_dma { enum dma_data_direction dma_data_dir; }; +enum imx_i2c_state { + IMX_I2C_STATE_DONE, + IMX_I2C_STATE_FAILED, + IMX_I2C_STATE_WRITE, + IMX_I2C_STATE_DMA, + IMX_I2C_STATE_READ, + IMX_I2C_STATE_READ_CONTINUE, + IMX_I2C_STATE_READ_BLOCK_DATA, + IMX_I2C_STATE_READ_BLOCK_DATA_LEN, +}; + struct imx_i2c_struct { struct i2c_adapter adapter; struct clk *clk; @@ -216,6 +253,14 @@ struct imx_i2c_struct { struct i2c_client *slave; enum i2c_slave_event last_slave_event; + struct i2c_msg *msg; + unsigned int msg_buf_idx; + int isr_result; + bool is_lastmsg; + enum imx_i2c_state state; + + bool multi_master; + /* For checking slave events. */ spinlock_t slave_lock; struct hrtimer slave_timer; @@ -258,7 +303,15 @@ static struct imx_i2c_hwdata vf610_i2c_hwdata = { .ndivs = ARRAY_SIZE(vf610_i2c_clk_div), .i2sr_clr_opcode = I2SR_CLR_OPCODE_W1C, .i2cr_ien_opcode = I2CR_IEN_OPCODE_0, +}; +static const struct imx_i2c_hwdata s32g2_i2c_hwdata = { + .devtype = S32G_I2C, + .regshift = S32G_I2C_REGSHIFT, + .clk_div = s32g2_i2c_clk_div, + .ndivs = ARRAY_SIZE(s32g2_i2c_clk_div), + .i2sr_clr_opcode = I2SR_CLR_OPCODE_W1C, + .i2cr_ien_opcode = I2CR_IEN_OPCODE_0, }; static const struct platform_device_id imx_i2c_devtype[] = { @@ -282,12 +335,14 @@ static const struct of_device_id i2c_imx_dt_ids[] = { { .compatible = "fsl,imx6sll-i2c", .data = &imx6_i2c_hwdata, }, { .compatible = "fsl,imx6sx-i2c", .data = &imx6_i2c_hwdata, }, { .compatible = "fsl,imx6ul-i2c", .data = &imx6_i2c_hwdata, }, + { .compatible = "fsl,imx7d-i2c", .data = &imx6_i2c_hwdata, }, { .compatible = "fsl,imx7s-i2c", .data = &imx6_i2c_hwdata, }, { .compatible = "fsl,imx8mm-i2c", .data = &imx6_i2c_hwdata, }, { .compatible = "fsl,imx8mn-i2c", .data = &imx6_i2c_hwdata, }, { .compatible = "fsl,imx8mp-i2c", .data = &imx6_i2c_hwdata, }, { .compatible = "fsl,imx8mq-i2c", .data = &imx6_i2c_hwdata, }, { .compatible = "fsl,vf610-i2c", .data = &vf610_i2c_hwdata, }, + { .compatible = "nxp,s32g2-i2c", .data = &s32g2_i2c_hwdata, }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, i2c_imx_dt_ids); @@ -342,17 +397,16 @@ static void i2c_imx_reset_regs(struct imx_i2c_struct *i2c_imx) } /* Functions for DMA support */ -static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx, - dma_addr_t phy_addr) +static int i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx, dma_addr_t phy_addr) { struct imx_i2c_dma *dma; struct dma_slave_config dma_sconfig; - struct device *dev = &i2c_imx->adapter.dev; + struct device *dev = i2c_imx->adapter.dev.parent; int ret; dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL); if (!dma) - return; + return -ENOMEM; dma->chan_tx = dma_request_chan(dev, "tx"); if (IS_ERR(dma->chan_tx)) { @@ -397,7 +451,7 @@ static void i2c_imx_dma_request(struct imx_i2c_struct *i2c_imx, dev_info(dev, "using %s (tx) and %s (rx) for DMA transfers\n", dma_chan_name(dma->chan_tx), dma_chan_name(dma->chan_rx)); - return; + return 0; fail_rx: dma_release_channel(dma->chan_rx); @@ -405,6 +459,8 @@ fail_tx: dma_release_channel(dma->chan_tx); fail_al: devm_kfree(dev, dma); + + return ret; } static void i2c_imx_dma_callback(void *arg) @@ -478,6 +534,7 @@ static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx) static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool atomic) { + bool multi_master = i2c_imx->multi_master; unsigned long orig_jiffies = jiffies; unsigned int temp; @@ -485,12 +542,12 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool a temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); /* check for arbitration lost */ - if (temp & I2SR_IAL) { + if (multi_master && (temp & I2SR_IAL)) { i2c_imx_clear_irq(i2c_imx, I2SR_IAL); return -EAGAIN; } - if (for_busy && (temp & I2SR_IBB)) { + if (for_busy && (!multi_master || (temp & I2SR_IBB))) { i2c_imx->stopped = 0; break; } @@ -540,8 +597,8 @@ static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx, bool atomic) return -ETIMEDOUT; } - /* check for arbitration lost */ - if (i2c_imx->i2csr & I2SR_IAL) { + /* In multi-master mode check for arbitration lost */ + if (i2c_imx->multi_master && (i2c_imx->i2csr & I2SR_IAL)) { dev_dbg(&i2c_imx->adapter.dev, "<%s> Arbitration lost\n", __func__); i2c_imx_clear_irq(i2c_imx, I2SR_IAL); @@ -565,8 +622,8 @@ static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx) return 0; } -static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx, - unsigned int i2c_clk_rate) +static int i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx, + unsigned int i2c_clk_rate) { struct imx_i2c_clk_pair *i2c_clk_div = i2c_imx->hwdata->clk_div; unsigned int div; @@ -581,7 +638,11 @@ static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx, /* Divider value calculation */ if (i2c_imx->cur_clk == i2c_clk_rate) - return; + return 0; + + /* Keep the denominator of the following program always NOT equal to 0. */ + if (!(i2c_clk_rate / 2)) + return -EINVAL; i2c_imx->cur_clk = i2c_clk_rate; @@ -612,6 +673,8 @@ static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx, dev_dbg(&i2c_imx->adapter.dev, "IFDR[IC]=0x%x, REAL DIV=%d\n", i2c_clk_div[i].val, i2c_clk_div[i].div); #endif + + return 0; } static int i2c_imx_clk_notifier_call(struct notifier_block *nb, @@ -621,11 +684,12 @@ static int i2c_imx_clk_notifier_call(struct notifier_block *nb, struct imx_i2c_struct *i2c_imx = container_of(nb, struct imx_i2c_struct, clk_change_nb); + int ret = 0; if (action & POST_RATE_CHANGE) - i2c_imx_set_clk(i2c_imx, ndata->new_rate); + ret = i2c_imx_set_clk(i2c_imx, ndata->new_rate); - return NOTIFY_OK; + return notifier_from_errno(ret); } static int i2c_imx_start(struct imx_i2c_struct *i2c_imx, bool atomic) @@ -687,7 +751,7 @@ static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx, bool atomic) i2c_imx_bus_busy(i2c_imx, 0, atomic); /* Disable I2C controller */ - temp = i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN, + temp = i2c_imx->hwdata->i2cr_ien_opcode ^ I2CR_IEN; imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); } @@ -903,11 +967,156 @@ static int i2c_imx_unreg_slave(struct i2c_client *client) return ret; } +static inline int i2c_imx_isr_acked(struct imx_i2c_struct *i2c_imx) +{ + i2c_imx->isr_result = 0; + + if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) { + i2c_imx->state = IMX_I2C_STATE_FAILED; + i2c_imx->isr_result = -ENXIO; + wake_up(&i2c_imx->queue); + } + + return i2c_imx->isr_result; +} + +static inline int i2c_imx_isr_write(struct imx_i2c_struct *i2c_imx) +{ + int result; + + result = i2c_imx_isr_acked(i2c_imx); + if (result) + return result; + + if (i2c_imx->msg->len == i2c_imx->msg_buf_idx) + return 0; + + imx_i2c_write_reg(i2c_imx->msg->buf[i2c_imx->msg_buf_idx++], i2c_imx, IMX_I2C_I2DR); + + return 1; +} + +static inline int i2c_imx_isr_read(struct imx_i2c_struct *i2c_imx) +{ + int result; + unsigned int temp; + + result = i2c_imx_isr_acked(i2c_imx); + if (result) + return result; + + /* setup bus to read data */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp &= ~I2CR_MTX; + if (i2c_imx->msg->len - 1) + temp &= ~I2CR_TXAK; + + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */ + + return 0; +} + +static inline void i2c_imx_isr_read_continue(struct imx_i2c_struct *i2c_imx) +{ + unsigned int temp; + + if ((i2c_imx->msg->len - 1) == i2c_imx->msg_buf_idx) { + if (i2c_imx->is_lastmsg) { + /* + * It must generate STOP before read I2DR to prevent + * controller from generating another clock cycle + */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + if (!(temp & I2CR_MSTA)) + i2c_imx->stopped = 1; + temp &= ~(I2CR_MSTA | I2CR_MTX); + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + } else { + /* + * For i2c master receiver repeat restart operation like: + * read -> repeat MSTA -> read/write + * The controller must set MTX before read the last byte in + * the first read operation, otherwise the first read cost + * one extra clock cycle. + */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_MTX; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + } + } else if (i2c_imx->msg_buf_idx == (i2c_imx->msg->len - 2)) { + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_TXAK; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + } + + i2c_imx->msg->buf[i2c_imx->msg_buf_idx++] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); +} + +static inline void i2c_imx_isr_read_block_data_len(struct imx_i2c_struct *i2c_imx) +{ + u8 len = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); + + if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) { + i2c_imx->isr_result = -EPROTO; + i2c_imx->state = IMX_I2C_STATE_FAILED; + wake_up(&i2c_imx->queue); + } + i2c_imx->msg->len += len; +} + static irqreturn_t i2c_imx_master_isr(struct imx_i2c_struct *i2c_imx, unsigned int status) { - /* save status register */ - i2c_imx->i2csr = status; - wake_up(&i2c_imx->queue); + /* + * This state machine handles I2C reception and transmission in non-DMA + * mode. We must process all the data in the ISR to reduce the delay + * between two consecutive messages. If the data is not processed in + * the ISR, SMBus devices may timeout, leading to a bus error. + */ + switch (i2c_imx->state) { + case IMX_I2C_STATE_DMA: + i2c_imx->i2csr = status; + wake_up(&i2c_imx->queue); + break; + + case IMX_I2C_STATE_READ: + if (i2c_imx_isr_read(i2c_imx)) + break; + i2c_imx->state = IMX_I2C_STATE_READ_CONTINUE; + break; + + case IMX_I2C_STATE_READ_CONTINUE: + i2c_imx_isr_read_continue(i2c_imx); + if (i2c_imx->msg_buf_idx == i2c_imx->msg->len) { + i2c_imx->state = IMX_I2C_STATE_DONE; + wake_up(&i2c_imx->queue); + } + break; + + case IMX_I2C_STATE_READ_BLOCK_DATA: + if (i2c_imx_isr_read(i2c_imx)) + break; + i2c_imx->state = IMX_I2C_STATE_READ_BLOCK_DATA_LEN; + break; + + case IMX_I2C_STATE_READ_BLOCK_DATA_LEN: + i2c_imx_isr_read_block_data_len(i2c_imx); + i2c_imx->state = IMX_I2C_STATE_READ_CONTINUE; + break; + + case IMX_I2C_STATE_WRITE: + if (i2c_imx_isr_write(i2c_imx)) + break; + i2c_imx->state = IMX_I2C_STATE_DONE; + wake_up(&i2c_imx->queue); + break; + + default: + i2c_imx->i2csr = status; + i2c_imx->state = IMX_I2C_STATE_FAILED; + i2c_imx->isr_result = -EINVAL; + wake_up(&i2c_imx->queue); + } return IRQ_HANDLED; } @@ -954,6 +1163,8 @@ static int i2c_imx_dma_write(struct imx_i2c_struct *i2c_imx, struct imx_i2c_dma *dma = i2c_imx->dma; struct device *dev = &i2c_imx->adapter.dev; + i2c_imx->state = IMX_I2C_STATE_DMA; + dma->chan_using = dma->chan_tx; dma->dma_transfer_dir = DMA_MEM_TO_DEV; dma->dma_data_dir = DMA_TO_DEVICE; @@ -1006,6 +1217,42 @@ static int i2c_imx_dma_write(struct imx_i2c_struct *i2c_imx, return i2c_imx_acked(i2c_imx); } +static int i2c_imx_prepare_read(struct imx_i2c_struct *i2c_imx, + struct i2c_msg *msgs, bool use_dma) +{ + int result; + unsigned int temp = 0; + + /* write slave address */ + imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR); + result = i2c_imx_trx_complete(i2c_imx, !use_dma); + if (result) + return result; + result = i2c_imx_acked(i2c_imx); + if (result) + return result; + + dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__); + + /* setup bus to read data */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp &= ~I2CR_MTX; + + /* + * Reset the I2CR_TXAK flag initially for SMBus block read since the + * length is unknown + */ + if (msgs->len - 1) + temp &= ~I2CR_TXAK; + if (use_dma) + temp |= I2CR_DMAEN; + + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */ + + return 0; +} + static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, bool is_lastmsg) { @@ -1016,6 +1263,13 @@ static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx, struct imx_i2c_dma *dma = i2c_imx->dma; struct device *dev = &i2c_imx->adapter.dev; + i2c_imx->state = IMX_I2C_STATE_DMA; + + result = i2c_imx_prepare_read(i2c_imx, msgs, true); + if (result) + return result; + + dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__); dma->chan_using = dma->chan_rx; dma->dma_transfer_dir = DMA_DEV_TO_MEM; @@ -1092,8 +1346,8 @@ static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx, return 0; } -static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, - bool atomic) +static int i2c_imx_atomic_write(struct imx_i2c_struct *i2c_imx, + struct i2c_msg *msgs) { int i, result; @@ -1102,7 +1356,7 @@ static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, /* write slave address */ imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR); - result = i2c_imx_trx_complete(i2c_imx, atomic); + result = i2c_imx_trx_complete(i2c_imx, true); if (result) return result; result = i2c_imx_acked(i2c_imx); @@ -1116,7 +1370,7 @@ static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, "<%s> write byte: B%d=0x%X\n", __func__, i, msgs->buf[i]); imx_i2c_write_reg(msgs->buf[i], i2c_imx, IMX_I2C_I2DR); - result = i2c_imx_trx_complete(i2c_imx, atomic); + result = i2c_imx_trx_complete(i2c_imx, true); if (result) return result; result = i2c_imx_acked(i2c_imx); @@ -1126,55 +1380,54 @@ static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, return 0; } -static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, - bool is_lastmsg, bool atomic) +static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs) +{ + dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n", + __func__, i2c_8bit_addr_from_msg(msgs)); + + i2c_imx->state = IMX_I2C_STATE_WRITE; + i2c_imx->msg = msgs; + i2c_imx->msg_buf_idx = 0; + + /* + * By writing the device address we start the state machine in the ISR. + * The ISR will report when it is done or when it fails. + */ + imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR); + wait_event_timeout(i2c_imx->queue, + i2c_imx->state == IMX_I2C_STATE_DONE || + i2c_imx->state == IMX_I2C_STATE_FAILED, + (msgs->len + 1) * HZ / 10); + if (i2c_imx->state == IMX_I2C_STATE_FAILED) { + dev_dbg(&i2c_imx->adapter.dev, "<%s> write failed with %d\n", + __func__, i2c_imx->isr_result); + return i2c_imx->isr_result; + } + if (i2c_imx->state != IMX_I2C_STATE_DONE) { + dev_err(&i2c_imx->adapter.dev, "<%s> write timedout\n", __func__); + return -ETIMEDOUT; + } + return 0; +} + +static int i2c_imx_atomic_read(struct imx_i2c_struct *i2c_imx, + struct i2c_msg *msgs, bool is_lastmsg) { int i, result; unsigned int temp; int block_data = msgs->flags & I2C_M_RECV_LEN; - int use_dma = i2c_imx->dma && msgs->flags & I2C_M_DMA_SAFE && - msgs->len >= DMA_THRESHOLD && !block_data; - dev_dbg(&i2c_imx->adapter.dev, - "<%s> write slave address: addr=0x%x\n", - __func__, i2c_8bit_addr_from_msg(msgs)); - - /* write slave address */ - imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR); - result = i2c_imx_trx_complete(i2c_imx, atomic); - if (result) - return result; - result = i2c_imx_acked(i2c_imx); + result = i2c_imx_prepare_read(i2c_imx, msgs, false); if (result) return result; - dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__); - - /* setup bus to read data */ - temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); - temp &= ~I2CR_MTX; - - /* - * Reset the I2CR_TXAK flag initially for SMBus block read since the - * length is unknown - */ - if ((msgs->len - 1) || block_data) - temp &= ~I2CR_TXAK; - if (use_dma) - temp |= I2CR_DMAEN; - imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); - imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */ - dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__); - if (use_dma) - return i2c_imx_dma_read(i2c_imx, msgs, is_lastmsg); - /* read data */ for (i = 0; i < msgs->len; i++) { u8 len = 0; - result = i2c_imx_trx_complete(i2c_imx, atomic); + result = i2c_imx_trx_complete(i2c_imx, true); if (result) return result; /* @@ -1205,7 +1458,7 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, temp &= ~(I2CR_MSTA | I2CR_MTX); imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); if (!i2c_imx->stopped) - i2c_imx_bus_busy(i2c_imx, 0, atomic); + i2c_imx_bus_busy(i2c_imx, 0, true); } else { /* * For i2c master receiver repeat restart operation like: @@ -1236,6 +1489,48 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, return 0; } +static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, + bool is_lastmsg) +{ + int block_data = msgs->flags & I2C_M_RECV_LEN; + + dev_dbg(&i2c_imx->adapter.dev, + "<%s> write slave address: addr=0x%x\n", + __func__, i2c_8bit_addr_from_msg(msgs)); + + i2c_imx->is_lastmsg = is_lastmsg; + + if (block_data) + i2c_imx->state = IMX_I2C_STATE_READ_BLOCK_DATA; + else + i2c_imx->state = IMX_I2C_STATE_READ; + i2c_imx->msg = msgs; + i2c_imx->msg_buf_idx = 0; + + /* + * By writing the device address we start the state machine in the ISR. + * The ISR will report when it is done or when it fails. + */ + imx_i2c_write_reg(i2c_8bit_addr_from_msg(msgs), i2c_imx, IMX_I2C_I2DR); + wait_event_timeout(i2c_imx->queue, + i2c_imx->state == IMX_I2C_STATE_DONE || + i2c_imx->state == IMX_I2C_STATE_FAILED, + (msgs->len + 1) * HZ / 10); + if (i2c_imx->state == IMX_I2C_STATE_FAILED) { + dev_dbg(&i2c_imx->adapter.dev, "<%s> read failed with %d\n", + __func__, i2c_imx->isr_result); + return i2c_imx->isr_result; + } + if (i2c_imx->state != IMX_I2C_STATE_DONE) { + dev_err(&i2c_imx->adapter.dev, "<%s> read timedout\n", __func__); + return -ETIMEDOUT; + } + if (!i2c_imx->stopped) + return i2c_imx_bus_busy(i2c_imx, 0, false); + + return 0; +} + static int i2c_imx_xfer_common(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num, bool atomic) { @@ -1243,6 +1538,7 @@ static int i2c_imx_xfer_common(struct i2c_adapter *adapter, int result; bool is_lastmsg = false; struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter); + int use_dma = 0; /* Start I2C transfer */ result = i2c_imx_start(i2c_imx, atomic); @@ -1295,15 +1591,25 @@ static int i2c_imx_xfer_common(struct i2c_adapter *adapter, (temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0), (temp & I2SR_RXAK ? 1 : 0)); #endif + + use_dma = i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD && + msgs[i].flags & I2C_M_DMA_SAFE; if (msgs[i].flags & I2C_M_RD) { - result = i2c_imx_read(i2c_imx, &msgs[i], is_lastmsg, atomic); + int block_data = msgs->flags & I2C_M_RECV_LEN; + + if (atomic) + result = i2c_imx_atomic_read(i2c_imx, &msgs[i], is_lastmsg); + else if (use_dma && !block_data) + result = i2c_imx_dma_read(i2c_imx, &msgs[i], is_lastmsg); + else + result = i2c_imx_read(i2c_imx, &msgs[i], is_lastmsg); } else { - if (!atomic && - i2c_imx->dma && msgs[i].len >= DMA_THRESHOLD && - msgs[i].flags & I2C_M_DMA_SAFE) + if (atomic) + result = i2c_imx_atomic_write(i2c_imx, &msgs[i]); + else if (use_dma) result = i2c_imx_dma_write(i2c_imx, &msgs[i]); else - result = i2c_imx_write(i2c_imx, &msgs[i], atomic); + result = i2c_imx_write(i2c_imx, &msgs[i]); } if (result) goto fail0; @@ -1405,11 +1711,11 @@ static int i2c_imx_probe(struct platform_device *pdev) irq = platform_get_irq(pdev, 0); if (irq < 0) - return irq; + return dev_err_probe(&pdev->dev, irq, "can't get IRQ\n"); base = devm_platform_get_and_ioremap_resource(pdev, 0, &res); if (IS_ERR(base)) - return PTR_ERR(base); + return dev_err_probe(&pdev->dev, PTR_ERR(base), "can't get IO memory\n"); phy_addr = (dma_addr_t)res->start; i2c_imx = devm_kzalloc(&pdev->dev, sizeof(*i2c_imx), GFP_KERNEL); @@ -1417,8 +1723,8 @@ static int i2c_imx_probe(struct platform_device *pdev) return -ENOMEM; spin_lock_init(&i2c_imx->slave_lock); - hrtimer_init(&i2c_imx->slave_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); - i2c_imx->slave_timer.function = i2c_imx_slave_timeout; + hrtimer_setup(&i2c_imx->slave_timer, i2c_imx_slave_timeout, CLOCK_MONOTONIC, + HRTIMER_MODE_ABS); match = device_get_match_data(&pdev->dev); if (match) @@ -1462,12 +1768,19 @@ static int i2c_imx_probe(struct platform_device *pdev) goto rpm_disable; /* Request IRQ */ - ret = request_irq(irq, i2c_imx_isr, IRQF_SHARED, pdev->name, i2c_imx); + ret = request_irq(irq, i2c_imx_isr, IRQF_SHARED | IRQF_NO_SUSPEND, + pdev->name, i2c_imx); if (ret) { dev_err(&pdev->dev, "can't claim irq %d\n", irq); goto rpm_disable; } + /* + * We use the single-master property for backward compatibility. + * By default multi master mode is enabled. + */ + i2c_imx->multi_master = !of_property_read_bool(pdev->dev.of_node, "single-master"); + /* Set up clock divider */ i2c_imx->bitrate = I2C_MAX_STANDARD_MODE_FREQ; ret = of_property_read_u32(pdev->dev.of_node, @@ -1476,7 +1789,11 @@ static int i2c_imx_probe(struct platform_device *pdev) i2c_imx->bitrate = pdata->bitrate; i2c_imx->clk_change_nb.notifier_call = i2c_imx_clk_notifier_call; clk_notifier_register(i2c_imx->clk, &i2c_imx->clk_change_nb); - i2c_imx_set_clk(i2c_imx, clk_get_rate(i2c_imx->clk)); + ret = i2c_imx_set_clk(i2c_imx, clk_get_rate(i2c_imx->clk)); + if (ret < 0) { + dev_err(&pdev->dev, "can't get I2C clock\n"); + goto clk_notifier_unregister; + } i2c_imx_reset_regs(i2c_imx); @@ -1486,6 +1803,24 @@ static int i2c_imx_probe(struct platform_device *pdev) if (ret == -EPROBE_DEFER) goto clk_notifier_unregister; + /* + * DMA mode should be optional for I2C, when encountering DMA errors, + * no need to exit I2C probe. Only print warning to show DMA error and + * use PIO mode directly to ensure I2C bus available as much as possible. + */ + ret = i2c_imx_dma_request(i2c_imx, phy_addr); + if (ret) { + if (ret == -EPROBE_DEFER) { + dev_err_probe(&pdev->dev, ret, "can't get DMA channels\n"); + goto clk_notifier_unregister; + } else if (ret == -ENODEV) { + dev_dbg(&pdev->dev, "Only use PIO mode\n"); + } else { + dev_warn(&pdev->dev, "Failed to setup DMA (%pe), only use PIO mode\n", + ERR_PTR(ret)); + } + } + /* Add I2C adapter */ ret = i2c_add_numbered_adapter(&i2c_imx->adapter); if (ret < 0) @@ -1500,9 +1835,6 @@ static int i2c_imx_probe(struct platform_device *pdev) i2c_imx->adapter.name); dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n"); - /* Init DMA config if supported */ - i2c_imx_dma_request(i2c_imx, phy_addr); - return 0; /* Return OK */ clk_notifier_unregister: @@ -1549,20 +1881,23 @@ static void i2c_imx_remove(struct platform_device *pdev) pm_runtime_disable(&pdev->dev); } -static int __maybe_unused i2c_imx_runtime_suspend(struct device *dev) +static int i2c_imx_runtime_suspend(struct device *dev) { struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev); clk_disable(i2c_imx->clk); - - return 0; + return pinctrl_pm_select_sleep_state(dev); } -static int __maybe_unused i2c_imx_runtime_resume(struct device *dev) +static int i2c_imx_runtime_resume(struct device *dev) { struct imx_i2c_struct *i2c_imx = dev_get_drvdata(dev); int ret; + ret = pinctrl_pm_select_default_state(dev); + if (ret) + return ret; + ret = clk_enable(i2c_imx->clk); if (ret) dev_err(dev, "can't enable I2C clock, ret=%d\n", ret); @@ -1570,17 +1905,52 @@ static int __maybe_unused i2c_imx_runtime_resume(struct device *dev) return ret; } +static int i2c_imx_suspend(struct device *dev) +{ + /* + * Some I2C devices may need the I2C controller to remain active + * during resume_noirq() or suspend_noirq(). If the controller is + * autosuspended, there is no way to wake it up once runtime PM is + * disabled (in suspend_late()). + * + * During system resume, the I2C controller will be available only + * after runtime PM is re-enabled (in resume_early()). However, this + * may be too late for some devices. + * + * Wake up the controller in the suspend() callback while runtime PM + * is still enabled. The I2C controller will remain available until + * the suspend_noirq() callback (pm_runtime_force_suspend()) is + * called. During resume, the I2C controller can be restored by the + * resume_noirq() callback (pm_runtime_force_resume()). + * + * Finally, the resume() callback re-enables autosuspend, ensuring + * the I2C controller remains available until the system enters + * suspend_noirq() and from resume_noirq(). + */ + return pm_runtime_resume_and_get(dev); +} + +static int i2c_imx_resume(struct device *dev) +{ + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + + return 0; +} + static const struct dev_pm_ops i2c_imx_pm_ops = { - SET_RUNTIME_PM_OPS(i2c_imx_runtime_suspend, - i2c_imx_runtime_resume, NULL) + NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) + SYSTEM_SLEEP_PM_OPS(i2c_imx_suspend, i2c_imx_resume) + RUNTIME_PM_OPS(i2c_imx_runtime_suspend, i2c_imx_runtime_resume, NULL) }; static struct platform_driver i2c_imx_driver = { .probe = i2c_imx_probe, - .remove_new = i2c_imx_remove, + .remove = i2c_imx_remove, .driver = { .name = DRIVER_NAME, - .pm = &i2c_imx_pm_ops, + .pm = pm_ptr(&i2c_imx_pm_ops), .of_match_table = i2c_imx_dt_ids, .acpi_match_table = i2c_imx_acpi_ids, }, |