| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Wolfram Sang | 1965 | 47.22% | 50 | 61.73% |
| Magnus Damm | 1701 | 40.88% | 11 | 13.58% |
| Guennadi Liakhovetski | 234 | 5.62% | 4 | 4.94% |
| Shinya Kuribayashi | 167 | 4.01% | 4 | 4.94% |
| Simon Horman | 45 | 1.08% | 2 | 2.47% |
| Geert Uytterhoeven | 19 | 0.46% | 2 | 2.47% |
| Fabrizio Castro | 13 | 0.31% | 1 | 1.23% |
| Eugeniu Rosca | 5 | 0.12% | 1 | 1.23% |
| Jean Delvare | 4 | 0.10% | 1 | 1.23% |
| Andy Shevchenko | 3 | 0.07% | 1 | 1.23% |
| Tejun Heo | 2 | 0.05% | 1 | 1.23% |
| Yong Zhang | 1 | 0.02% | 1 | 1.23% |
| Bhumika Goyal | 1 | 0.02% | 1 | 1.23% |
| Peter Ujfalusi | 1 | 0.02% | 1 | 1.23% |
| Total | 4161 | 81 |
// SPDX-License-Identifier: GPL-2.0 /* * SuperH Mobile I2C Controller * * Copyright (C) 2014-19 Wolfram Sang <wsa@sang-engineering.com> * Copyright (C) 2008 Magnus Damm * * Portions of the code based on out-of-tree driver i2c-sh7343.c * Copyright (c) 2006 Carlos Munoz <carlos@kenati.com> */ #include <linux/clk.h> #include <linux/delay.h> #include <linux/dmaengine.h> #include <linux/dma-mapping.h> #include <linux/err.h> #include <linux/i2c.h> #include <linux/init.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <linux/slab.h> /* Transmit operation: */ /* */ /* 0 byte transmit */ /* BUS: S A8 ACK P(*) */ /* IRQ: DTE WAIT */ /* ICIC: */ /* ICCR: 0x94 0x90 */ /* ICDR: A8 */ /* */ /* 1 byte transmit */ /* BUS: S A8 ACK D8(1) ACK P(*) */ /* IRQ: DTE WAIT WAIT */ /* ICIC: -DTE */ /* ICCR: 0x94 0x90 */ /* ICDR: A8 D8(1) */ /* */ /* 2 byte transmit */ /* BUS: S A8 ACK D8(1) ACK D8(2) ACK P(*) */ /* IRQ: DTE WAIT WAIT WAIT */ /* ICIC: -DTE */ /* ICCR: 0x94 0x90 */ /* ICDR: A8 D8(1) D8(2) */ /* */ /* 3 bytes or more, +---------+ gets repeated */ /* */ /* */ /* Receive operation: */ /* */ /* 0 byte receive - not supported since slave may hold SDA low */ /* */ /* 1 byte receive [TX] | [RX] */ /* BUS: S A8 ACK | D8(1) ACK P(*) */ /* IRQ: DTE WAIT | WAIT DTE */ /* ICIC: -DTE | +DTE */ /* ICCR: 0x94 0x81 | 0xc0 */ /* ICDR: A8 | D8(1) */ /* */ /* 2 byte receive [TX]| [RX] */ /* BUS: S A8 ACK | D8(1) ACK D8(2) ACK P(*) */ /* IRQ: DTE WAIT | WAIT WAIT DTE */ /* ICIC: -DTE | +DTE */ /* ICCR: 0x94 0x81 | 0xc0 */ /* ICDR: A8 | D8(1) D8(2) */ /* */ /* 3 byte receive [TX] | [RX] (*) */ /* BUS: S A8 ACK | D8(1) ACK D8(2) ACK D8(3) ACK P */ /* IRQ: DTE WAIT | WAIT WAIT WAIT DTE */ /* ICIC: -DTE | +DTE */ /* ICCR: 0x94 0x81 | 0xc0 */ /* ICDR: A8 | D8(1) D8(2) D8(3) */ /* */ /* 4 bytes or more, this part is repeated +---------+ */ /* */ /* */ /* Interrupt order and BUSY flag */ /* ___ _ */ /* SDA ___\___XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXAAAAAAAAA___/ */ /* SCL \_/1\_/2\_/3\_/4\_/5\_/6\_/7\_/8\___/9\_____/ */ /* */ /* S D7 D6 D5 D4 D3 D2 D1 D0 P(*) */ /* ___ */ /* WAIT IRQ ________________________________/ \___________ */ /* TACK IRQ ____________________________________/ \_______ */ /* DTE IRQ __________________________________________/ \_ */ /* AL IRQ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX */ /* _______________________________________________ */ /* BUSY __/ \_ */ /* */ /* (*) The STOP condition is only sent by the master at the end of the last */ /* I2C message or if the I2C_M_STOP flag is set. Similarly, the BUSY bit is */ /* only cleared after the STOP condition, so, between messages we have to */ /* poll for the DTE bit. */ /* */ enum sh_mobile_i2c_op { OP_START = 0, OP_TX_FIRST, OP_TX, OP_TX_STOP, OP_TX_TO_RX, OP_RX, OP_RX_STOP, OP_RX_STOP_DATA, }; struct sh_mobile_i2c_data { struct device *dev; void __iomem *reg; struct i2c_adapter adap; unsigned long bus_speed; unsigned int clks_per_count; struct clk *clk; u_int8_t icic; u_int8_t flags; u_int16_t iccl; u_int16_t icch; spinlock_t lock; wait_queue_head_t wait; struct i2c_msg *msg; int pos; int sr; bool send_stop; bool stop_after_dma; struct resource *res; struct dma_chan *dma_tx; struct dma_chan *dma_rx; struct scatterlist sg; enum dma_data_direction dma_direction; u8 *dma_buf; }; struct sh_mobile_dt_config { int clks_per_count; int (*setup)(struct sh_mobile_i2c_data *pd); }; #define IIC_FLAG_HAS_ICIC67 (1 << 0) /* Register offsets */ #define ICDR 0x00 #define ICCR 0x04 #define ICSR 0x08 #define ICIC 0x0c #define ICCL 0x10 #define ICCH 0x14 #define ICSTART 0x70 /* Register bits */ #define ICCR_ICE 0x80 #define ICCR_RACK 0x40 #define ICCR_TRS 0x10 #define ICCR_BBSY 0x04 #define ICCR_SCP 0x01 #define ICSR_SCLM 0x80 #define ICSR_SDAM 0x40 #define SW_DONE 0x20 #define ICSR_BUSY 0x10 #define ICSR_AL 0x08 #define ICSR_TACK 0x04 #define ICSR_WAIT 0x02 #define ICSR_DTE 0x01 #define ICIC_ICCLB8 0x80 #define ICIC_ICCHB8 0x40 #define ICIC_TDMAE 0x20 #define ICIC_RDMAE 0x10 #define ICIC_ALE 0x08 #define ICIC_TACKE 0x04 #define ICIC_WAITE 0x02 #define ICIC_DTEE 0x01 #define ICSTART_ICSTART 0x10 static void iic_wr(struct sh_mobile_i2c_data *pd, int offs, unsigned char data) { if (offs == ICIC) data |= pd->icic; iowrite8(data, pd->reg + offs); } static unsigned char iic_rd(struct sh_mobile_i2c_data *pd, int offs) { return ioread8(pd->reg + offs); } static void iic_set_clr(struct sh_mobile_i2c_data *pd, int offs, unsigned char set, unsigned char clr) { iic_wr(pd, offs, (iic_rd(pd, offs) | set) & ~clr); } static u32 sh_mobile_i2c_iccl(unsigned long count_khz, u32 tLOW, u32 tf) { /* * Conditional expression: * ICCL >= COUNT_CLK * (tLOW + tf) * * SH-Mobile IIC hardware starts counting the LOW period of * the SCL signal (tLOW) as soon as it pulls the SCL line. * In order to meet the tLOW timing spec, we need to take into * account the fall time of SCL signal (tf). Default tf value * should be 0.3 us, for safety. */ return (((count_khz * (tLOW + tf)) + 5000) / 10000); } static u32 sh_mobile_i2c_icch(unsigned long count_khz, u32 tHIGH, u32 tf) { /* * Conditional expression: * ICCH >= COUNT_CLK * (tHIGH + tf) * * SH-Mobile IIC hardware is aware of SCL transition period 'tr', * and can ignore it. SH-Mobile IIC controller starts counting * the HIGH period of the SCL signal (tHIGH) after the SCL input * voltage increases at VIH. * * Afterward it turned out calculating ICCH using only tHIGH spec * will result in violation of the tHD;STA timing spec. We need * to take into account the fall time of SDA signal (tf) at START * condition, in order to meet both tHIGH and tHD;STA specs. */ return (((count_khz * (tHIGH + tf)) + 5000) / 10000); } static int sh_mobile_i2c_check_timing(struct sh_mobile_i2c_data *pd) { u16 max_val = pd->flags & IIC_FLAG_HAS_ICIC67 ? 0x1ff : 0xff; if (pd->iccl > max_val || pd->icch > max_val) { dev_err(pd->dev, "timing values out of range: L/H=0x%x/0x%x\n", pd->iccl, pd->icch); return -EINVAL; } /* one more bit of ICCL in ICIC */ if (pd->iccl & 0x100) pd->icic |= ICIC_ICCLB8; else pd->icic &= ~ICIC_ICCLB8; /* one more bit of ICCH in ICIC */ if (pd->icch & 0x100) pd->icic |= ICIC_ICCHB8; else pd->icic &= ~ICIC_ICCHB8; dev_dbg(pd->dev, "timing values: L/H=0x%x/0x%x\n", pd->iccl, pd->icch); return 0; } static int sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd) { unsigned long i2c_clk_khz; u32 tHIGH, tLOW, tf; i2c_clk_khz = clk_get_rate(pd->clk) / 1000 / pd->clks_per_count; if (pd->bus_speed == I2C_MAX_STANDARD_MODE_FREQ) { tLOW = 47; /* tLOW = 4.7 us */ tHIGH = 40; /* tHD;STA = tHIGH = 4.0 us */ tf = 3; /* tf = 0.3 us */ } else if (pd->bus_speed == I2C_MAX_FAST_MODE_FREQ) { tLOW = 13; /* tLOW = 1.3 us */ tHIGH = 6; /* tHD;STA = tHIGH = 0.6 us */ tf = 3; /* tf = 0.3 us */ } else { dev_err(pd->dev, "unrecognized bus speed %lu Hz\n", pd->bus_speed); return -EINVAL; } pd->iccl = sh_mobile_i2c_iccl(i2c_clk_khz, tLOW, tf); pd->icch = sh_mobile_i2c_icch(i2c_clk_khz, tHIGH, tf); return sh_mobile_i2c_check_timing(pd); } static int sh_mobile_i2c_v2_init(struct sh_mobile_i2c_data *pd) { unsigned long clks_per_cycle; /* L = 5, H = 4, L + H = 9 */ clks_per_cycle = clk_get_rate(pd->clk) / pd->bus_speed; pd->iccl = DIV_ROUND_UP(clks_per_cycle * 5 / 9 - 1, pd->clks_per_count); pd->icch = DIV_ROUND_UP(clks_per_cycle * 4 / 9 - 5, pd->clks_per_count); return sh_mobile_i2c_check_timing(pd); } static unsigned char i2c_op(struct sh_mobile_i2c_data *pd, enum sh_mobile_i2c_op op) { unsigned char ret = 0; unsigned long flags; dev_dbg(pd->dev, "op %d\n", op); spin_lock_irqsave(&pd->lock, flags); switch (op) { case OP_START: /* issue start and trigger DTE interrupt */ iic_wr(pd, ICCR, ICCR_ICE | ICCR_TRS | ICCR_BBSY); break; case OP_TX_FIRST: /* disable DTE interrupt and write client address */ iic_wr(pd, ICIC, ICIC_WAITE | ICIC_ALE | ICIC_TACKE); iic_wr(pd, ICDR, i2c_8bit_addr_from_msg(pd->msg)); break; case OP_TX: /* write data */ iic_wr(pd, ICDR, pd->msg->buf[pd->pos]); break; case OP_TX_STOP: /* issue a stop (or rep_start) */ iic_wr(pd, ICCR, pd->send_stop ? ICCR_ICE | ICCR_TRS : ICCR_ICE | ICCR_TRS | ICCR_BBSY); break; case OP_TX_TO_RX: /* select read mode */ iic_wr(pd, ICCR, ICCR_ICE | ICCR_SCP); break; case OP_RX: /* just read data */ ret = iic_rd(pd, ICDR); break; case OP_RX_STOP: /* enable DTE interrupt, issue stop */ iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); iic_wr(pd, ICCR, ICCR_ICE | ICCR_RACK); break; case OP_RX_STOP_DATA: /* enable DTE interrupt, read data, issue stop */ iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); ret = iic_rd(pd, ICDR); iic_wr(pd, ICCR, ICCR_ICE | ICCR_RACK); break; } spin_unlock_irqrestore(&pd->lock, flags); dev_dbg(pd->dev, "op %d, data out 0x%02x\n", op, ret); return ret; } static int sh_mobile_i2c_isr_tx(struct sh_mobile_i2c_data *pd) { if (pd->pos == pd->msg->len) { i2c_op(pd, OP_TX_STOP); return 1; } if (pd->pos == -1) i2c_op(pd, OP_TX_FIRST); else i2c_op(pd, OP_TX); pd->pos++; return 0; } static int sh_mobile_i2c_isr_rx(struct sh_mobile_i2c_data *pd) { unsigned char data; int real_pos; /* switch from TX (address) to RX (data) adds two interrupts */ real_pos = pd->pos - 2; if (pd->pos == -1) { i2c_op(pd, OP_TX_FIRST); } else if (pd->pos == 0) { i2c_op(pd, OP_TX_TO_RX); } else if (pd->pos == pd->msg->len) { if (pd->stop_after_dma) { /* Simulate PIO end condition after DMA transfer */ i2c_op(pd, OP_RX_STOP); pd->pos++; goto done; } if (real_pos < 0) i2c_op(pd, OP_RX_STOP); else data = i2c_op(pd, OP_RX_STOP_DATA); } else if (real_pos >= 0) { data = i2c_op(pd, OP_RX); } if (real_pos >= 0) pd->msg->buf[real_pos] = data; done: pd->pos++; return pd->pos == (pd->msg->len + 2); } static irqreturn_t sh_mobile_i2c_isr(int irq, void *dev_id) { struct sh_mobile_i2c_data *pd = dev_id; unsigned char sr; int wakeup = 0; sr = iic_rd(pd, ICSR); pd->sr |= sr; /* remember state */ dev_dbg(pd->dev, "i2c_isr 0x%02x 0x%02x %s %d %d!\n", sr, pd->sr, (pd->msg->flags & I2C_M_RD) ? "read" : "write", pd->pos, pd->msg->len); /* Kick off TxDMA after preface was done */ if (pd->dma_direction == DMA_TO_DEVICE && pd->pos == 0) iic_set_clr(pd, ICIC, ICIC_TDMAE, 0); else if (sr & (ICSR_AL | ICSR_TACK)) /* don't interrupt transaction - continue to issue stop */ iic_wr(pd, ICSR, sr & ~(ICSR_AL | ICSR_TACK)); else if (pd->msg->flags & I2C_M_RD) wakeup = sh_mobile_i2c_isr_rx(pd); else wakeup = sh_mobile_i2c_isr_tx(pd); /* Kick off RxDMA after preface was done */ if (pd->dma_direction == DMA_FROM_DEVICE && pd->pos == 1) iic_set_clr(pd, ICIC, ICIC_RDMAE, 0); if (sr & ICSR_WAIT) /* TODO: add delay here to support slow acks */ iic_wr(pd, ICSR, sr & ~ICSR_WAIT); if (wakeup) { pd->sr |= SW_DONE; wake_up(&pd->wait); } /* defeat write posting to avoid spurious WAIT interrupts */ iic_rd(pd, ICSR); return IRQ_HANDLED; } static void sh_mobile_i2c_dma_unmap(struct sh_mobile_i2c_data *pd) { struct dma_chan *chan = pd->dma_direction == DMA_FROM_DEVICE ? pd->dma_rx : pd->dma_tx; dma_unmap_single(chan->device->dev, sg_dma_address(&pd->sg), pd->msg->len, pd->dma_direction); pd->dma_direction = DMA_NONE; } static void sh_mobile_i2c_cleanup_dma(struct sh_mobile_i2c_data *pd) { if (pd->dma_direction == DMA_NONE) return; else if (pd->dma_direction == DMA_FROM_DEVICE) dmaengine_terminate_all(pd->dma_rx); else if (pd->dma_direction == DMA_TO_DEVICE) dmaengine_terminate_all(pd->dma_tx); sh_mobile_i2c_dma_unmap(pd); } static void sh_mobile_i2c_dma_callback(void *data) { struct sh_mobile_i2c_data *pd = data; sh_mobile_i2c_dma_unmap(pd); pd->pos = pd->msg->len; pd->stop_after_dma = true; iic_set_clr(pd, ICIC, 0, ICIC_TDMAE | ICIC_RDMAE); } static struct dma_chan *sh_mobile_i2c_request_dma_chan(struct device *dev, enum dma_transfer_direction dir, dma_addr_t port_addr) { struct dma_chan *chan; struct dma_slave_config cfg; char *chan_name = dir == DMA_MEM_TO_DEV ? "tx" : "rx"; int ret; chan = dma_request_chan(dev, chan_name); if (IS_ERR(chan)) { dev_dbg(dev, "request_channel failed for %s (%ld)\n", chan_name, PTR_ERR(chan)); return chan; } memset(&cfg, 0, sizeof(cfg)); cfg.direction = dir; if (dir == DMA_MEM_TO_DEV) { cfg.dst_addr = port_addr; cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; } else { cfg.src_addr = port_addr; cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE; } ret = dmaengine_slave_config(chan, &cfg); if (ret) { dev_dbg(dev, "slave_config failed for %s (%d)\n", chan_name, ret); dma_release_channel(chan); return ERR_PTR(ret); } dev_dbg(dev, "got DMA channel for %s\n", chan_name); return chan; } static void sh_mobile_i2c_xfer_dma(struct sh_mobile_i2c_data *pd) { bool read = pd->msg->flags & I2C_M_RD; enum dma_data_direction dir = read ? DMA_FROM_DEVICE : DMA_TO_DEVICE; struct dma_chan *chan = read ? pd->dma_rx : pd->dma_tx; struct dma_async_tx_descriptor *txdesc; dma_addr_t dma_addr; dma_cookie_t cookie; if (PTR_ERR(chan) == -EPROBE_DEFER) { if (read) chan = pd->dma_rx = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_DEV_TO_MEM, pd->res->start + ICDR); else chan = pd->dma_tx = sh_mobile_i2c_request_dma_chan(pd->dev, DMA_MEM_TO_DEV, pd->res->start + ICDR); } if (IS_ERR(chan)) return; dma_addr = dma_map_single(chan->device->dev, pd->dma_buf, pd->msg->len, dir); if (dma_mapping_error(chan->device->dev, dma_addr)) { dev_dbg(pd->dev, "dma map failed, using PIO\n"); return; } sg_dma_len(&pd->sg) = pd->msg->len; sg_dma_address(&pd->sg) = dma_addr; pd->dma_direction = dir; txdesc = dmaengine_prep_slave_sg(chan, &pd->sg, 1, read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!txdesc) { dev_dbg(pd->dev, "dma prep slave sg failed, using PIO\n"); sh_mobile_i2c_cleanup_dma(pd); return; } txdesc->callback = sh_mobile_i2c_dma_callback; txdesc->callback_param = pd; cookie = dmaengine_submit(txdesc); if (dma_submit_error(cookie)) { dev_dbg(pd->dev, "submitting dma failed, using PIO\n"); sh_mobile_i2c_cleanup_dma(pd); return; } dma_async_issue_pending(chan); } static void start_ch(struct sh_mobile_i2c_data *pd, struct i2c_msg *usr_msg, bool do_init) { if (do_init) { /* Initialize channel registers */ iic_wr(pd, ICCR, ICCR_SCP); /* Enable channel and configure rx ack */ iic_wr(pd, ICCR, ICCR_ICE | ICCR_SCP); /* Set the clock */ iic_wr(pd, ICCL, pd->iccl & 0xff); iic_wr(pd, ICCH, pd->icch & 0xff); } pd->msg = usr_msg; pd->pos = -1; pd->sr = 0; pd->dma_buf = i2c_get_dma_safe_msg_buf(pd->msg, 8); if (pd->dma_buf) sh_mobile_i2c_xfer_dma(pd); /* Enable all interrupts to begin with */ iic_wr(pd, ICIC, ICIC_DTEE | ICIC_WAITE | ICIC_ALE | ICIC_TACKE); } static int poll_dte(struct sh_mobile_i2c_data *pd) { int i; for (i = 1000; i; i--) { u_int8_t val = iic_rd(pd, ICSR); if (val & ICSR_DTE) break; if (val & ICSR_TACK) return -ENXIO; udelay(10); } return i ? 0 : -ETIMEDOUT; } static int poll_busy(struct sh_mobile_i2c_data *pd) { int i; for (i = 1000; i; i--) { u_int8_t val = iic_rd(pd, ICSR); dev_dbg(pd->dev, "val 0x%02x pd->sr 0x%02x\n", val, pd->sr); /* the interrupt handler may wake us up before the * transfer is finished, so poll the hardware * until we're done. */ if (!(val & ICSR_BUSY)) { /* handle missing acknowledge and arbitration lost */ val |= pd->sr; if (val & ICSR_TACK) return -ENXIO; if (val & ICSR_AL) return -EAGAIN; break; } udelay(10); } return i ? 0 : -ETIMEDOUT; } static int sh_mobile_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) { struct sh_mobile_i2c_data *pd = i2c_get_adapdata(adapter); struct i2c_msg *msg; int err = 0; int i; long timeout; /* Wake up device and enable clock */ pm_runtime_get_sync(pd->dev); /* Process all messages */ for (i = 0; i < num; i++) { bool do_start = pd->send_stop || !i; msg = &msgs[i]; pd->send_stop = i == num - 1 || msg->flags & I2C_M_STOP; pd->stop_after_dma = false; start_ch(pd, msg, do_start); if (do_start) i2c_op(pd, OP_START); /* The interrupt handler takes care of the rest... */ timeout = wait_event_timeout(pd->wait, pd->sr & (ICSR_TACK | SW_DONE), adapter->timeout); /* 'stop_after_dma' tells if DMA transfer was complete */ i2c_put_dma_safe_msg_buf(pd->dma_buf, pd->msg, pd->stop_after_dma); if (!timeout) { dev_err(pd->dev, "Transfer request timed out\n"); if (pd->dma_direction != DMA_NONE) sh_mobile_i2c_cleanup_dma(pd); err = -ETIMEDOUT; break; } if (pd->send_stop) err = poll_busy(pd); else err = poll_dte(pd); if (err < 0) break; } /* Disable channel */ iic_wr(pd, ICCR, ICCR_SCP); /* Disable clock and mark device as idle */ pm_runtime_put_sync(pd->dev); return err ?: num; } static u32 sh_mobile_i2c_func(struct i2c_adapter *adapter) { return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_PROTOCOL_MANGLING; } static const struct i2c_algorithm sh_mobile_i2c_algorithm = { .functionality = sh_mobile_i2c_func, .master_xfer = sh_mobile_i2c_xfer, }; static const struct i2c_adapter_quirks sh_mobile_i2c_quirks = { .flags = I2C_AQ_NO_ZERO_LEN_READ, }; /* * r8a7740 has an errata regarding I2C I/O pad reset needing this workaround. */ static int sh_mobile_i2c_r8a7740_workaround(struct sh_mobile_i2c_data *pd) { iic_set_clr(pd, ICCR, ICCR_ICE, 0); iic_rd(pd, ICCR); /* dummy read */ iic_set_clr(pd, ICSTART, ICSTART_ICSTART, 0); iic_rd(pd, ICSTART); /* dummy read */ udelay(10); iic_wr(pd, ICCR, ICCR_SCP); iic_wr(pd, ICSTART, 0); udelay(10); iic_wr(pd, ICCR, ICCR_TRS); udelay(10); iic_wr(pd, ICCR, 0); udelay(10); iic_wr(pd, ICCR, ICCR_TRS); udelay(10); return sh_mobile_i2c_init(pd); } static const struct sh_mobile_dt_config default_dt_config = { .clks_per_count = 1, .setup = sh_mobile_i2c_init, }; static const struct sh_mobile_dt_config fast_clock_dt_config = { .clks_per_count = 2, .setup = sh_mobile_i2c_init, }; static const struct sh_mobile_dt_config v2_freq_calc_dt_config = { .clks_per_count = 2, .setup = sh_mobile_i2c_v2_init, }; static const struct sh_mobile_dt_config r8a7740_dt_config = { .clks_per_count = 1, .setup = sh_mobile_i2c_r8a7740_workaround, }; static const struct of_device_id sh_mobile_i2c_dt_ids[] = { { .compatible = "renesas,iic-r8a73a4", .data = &fast_clock_dt_config }, { .compatible = "renesas,iic-r8a7740", .data = &r8a7740_dt_config }, { .compatible = "renesas,iic-r8a774c0", .data = &fast_clock_dt_config }, { .compatible = "renesas,iic-r8a7790", .data = &v2_freq_calc_dt_config }, { .compatible = "renesas,iic-r8a7791", .data = &v2_freq_calc_dt_config }, { .compatible = "renesas,iic-r8a7792", .data = &v2_freq_calc_dt_config }, { .compatible = "renesas,iic-r8a7793", .data = &v2_freq_calc_dt_config }, { .compatible = "renesas,iic-r8a7794", .data = &v2_freq_calc_dt_config }, { .compatible = "renesas,iic-r8a7795", .data = &v2_freq_calc_dt_config }, { .compatible = "renesas,iic-r8a77990", .data = &v2_freq_calc_dt_config }, { .compatible = "renesas,iic-sh73a0", .data = &fast_clock_dt_config }, { .compatible = "renesas,rcar-gen2-iic", .data = &v2_freq_calc_dt_config }, { .compatible = "renesas,rcar-gen3-iic", .data = &v2_freq_calc_dt_config }, { .compatible = "renesas,rmobile-iic", .data = &default_dt_config }, {}, }; MODULE_DEVICE_TABLE(of, sh_mobile_i2c_dt_ids); static void sh_mobile_i2c_release_dma(struct sh_mobile_i2c_data *pd) { if (!IS_ERR(pd->dma_tx)) { dma_release_channel(pd->dma_tx); pd->dma_tx = ERR_PTR(-EPROBE_DEFER); } if (!IS_ERR(pd->dma_rx)) { dma_release_channel(pd->dma_rx); pd->dma_rx = ERR_PTR(-EPROBE_DEFER); } } static int sh_mobile_i2c_hook_irqs(struct platform_device *dev, struct sh_mobile_i2c_data *pd) { struct resource *res; resource_size_t n; int k = 0, ret; while ((res = platform_get_resource(dev, IORESOURCE_IRQ, k))) { for (n = res->start; n <= res->end; n++) { ret = devm_request_irq(&dev->dev, n, sh_mobile_i2c_isr, 0, dev_name(&dev->dev), pd); if (ret) { dev_err(&dev->dev, "cannot request IRQ %pa\n", &n); return ret; } } k++; } return k > 0 ? 0 : -ENOENT; } static int sh_mobile_i2c_probe(struct platform_device *dev) { struct sh_mobile_i2c_data *pd; struct i2c_adapter *adap; struct resource *res; const struct sh_mobile_dt_config *config; int ret; u32 bus_speed; pd = devm_kzalloc(&dev->dev, sizeof(struct sh_mobile_i2c_data), GFP_KERNEL); if (!pd) return -ENOMEM; pd->clk = devm_clk_get(&dev->dev, NULL); if (IS_ERR(pd->clk)) { dev_err(&dev->dev, "cannot get clock\n"); return PTR_ERR(pd->clk); } ret = sh_mobile_i2c_hook_irqs(dev, pd); if (ret) return ret; pd->dev = &dev->dev; platform_set_drvdata(dev, pd); res = platform_get_resource(dev, IORESOURCE_MEM, 0); pd->res = res; pd->reg = devm_ioremap_resource(&dev->dev, res); if (IS_ERR(pd->reg)) return PTR_ERR(pd->reg); ret = of_property_read_u32(dev->dev.of_node, "clock-frequency", &bus_speed); pd->bus_speed = (ret || !bus_speed) ? I2C_MAX_STANDARD_MODE_FREQ : bus_speed; pd->clks_per_count = 1; /* Newer variants come with two new bits in ICIC */ if (resource_size(res) > 0x17) pd->flags |= IIC_FLAG_HAS_ICIC67; pm_runtime_enable(&dev->dev); pm_runtime_get_sync(&dev->dev); config = of_device_get_match_data(&dev->dev); if (config) { pd->clks_per_count = config->clks_per_count; ret = config->setup(pd); } else { ret = sh_mobile_i2c_init(pd); } pm_runtime_put_sync(&dev->dev); if (ret) return ret; /* Init DMA */ sg_init_table(&pd->sg, 1); pd->dma_direction = DMA_NONE; pd->dma_rx = pd->dma_tx = ERR_PTR(-EPROBE_DEFER); /* setup the private data */ adap = &pd->adap; i2c_set_adapdata(adap, pd); adap->owner = THIS_MODULE; adap->algo = &sh_mobile_i2c_algorithm; adap->quirks = &sh_mobile_i2c_quirks; adap->dev.parent = &dev->dev; adap->retries = 5; adap->nr = dev->id; adap->dev.of_node = dev->dev.of_node; strlcpy(adap->name, dev->name, sizeof(adap->name)); spin_lock_init(&pd->lock); init_waitqueue_head(&pd->wait); ret = i2c_add_numbered_adapter(adap); if (ret < 0) { sh_mobile_i2c_release_dma(pd); return ret; } dev_info(&dev->dev, "I2C adapter %d, bus speed %lu Hz\n", adap->nr, pd->bus_speed); return 0; } static int sh_mobile_i2c_remove(struct platform_device *dev) { struct sh_mobile_i2c_data *pd = platform_get_drvdata(dev); i2c_del_adapter(&pd->adap); sh_mobile_i2c_release_dma(pd); pm_runtime_disable(&dev->dev); return 0; } static struct platform_driver sh_mobile_i2c_driver = { .driver = { .name = "i2c-sh_mobile", .of_match_table = sh_mobile_i2c_dt_ids, }, .probe = sh_mobile_i2c_probe, .remove = sh_mobile_i2c_remove, }; static int __init sh_mobile_i2c_adap_init(void) { return platform_driver_register(&sh_mobile_i2c_driver); } subsys_initcall(sh_mobile_i2c_adap_init); static void __exit sh_mobile_i2c_adap_exit(void) { platform_driver_unregister(&sh_mobile_i2c_driver); } module_exit(sh_mobile_i2c_adap_exit); MODULE_DESCRIPTION("SuperH Mobile I2C Bus Controller driver"); MODULE_AUTHOR("Magnus Damm and Wolfram Sang"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("platform:i2c-sh_mobile");
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