| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Paul Mundt | 2031 | 98.98% | 1 | 8.33% |
| Wolfram Sang | 6 | 0.29% | 2 | 16.67% |
| Linus Walleij | 3 | 0.15% | 1 | 8.33% |
| Tejun Heo | 3 | 0.15% | 1 | 8.33% |
| Axel Lin | 2 | 0.10% | 1 | 8.33% |
| Harvey Harrison | 2 | 0.10% | 1 | 8.33% |
| Christoph Hellwig | 1 | 0.05% | 1 | 8.33% |
| Joe Perches | 1 | 0.05% | 1 | 8.33% |
| Krzysztof Kozlowski | 1 | 0.05% | 1 | 8.33% |
| Rusty Russell | 1 | 0.05% | 1 | 8.33% |
| Yong Zhang | 1 | 0.05% | 1 | 8.33% |
| Total | 2052 | 12 |
// SPDX-License-Identifier: GPL-2.0 /* * Renesas Solutions Highlander FPGA I2C/SMBus support. * * Supported devices: R0P7780LC0011RL, R0P7785LC0011RL * * Copyright (C) 2008 Paul Mundt * Copyright (C) 2008 Renesas Solutions Corp. * Copyright (C) 2008 Atom Create Engineering Co., Ltd. */ #include <linux/module.h> #include <linux/interrupt.h> #include <linux/i2c.h> #include <linux/platform_device.h> #include <linux/completion.h> #include <linux/io.h> #include <linux/delay.h> #include <linux/slab.h> #define SMCR 0x00 #define SMCR_START (1 << 0) #define SMCR_IRIC (1 << 1) #define SMCR_BBSY (1 << 2) #define SMCR_ACKE (1 << 3) #define SMCR_RST (1 << 4) #define SMCR_IEIC (1 << 6) #define SMSMADR 0x02 #define SMMR 0x04 #define SMMR_MODE0 (1 << 0) #define SMMR_MODE1 (1 << 1) #define SMMR_CAP (1 << 3) #define SMMR_TMMD (1 << 4) #define SMMR_SP (1 << 7) #define SMSADR 0x06 #define SMTRDR 0x46 struct highlander_i2c_dev { struct device *dev; void __iomem *base; struct i2c_adapter adapter; struct completion cmd_complete; unsigned long last_read_time; int irq; u8 *buf; size_t buf_len; }; static bool iic_force_poll, iic_force_normal; static int iic_timeout = 1000, iic_read_delay; static inline void highlander_i2c_irq_enable(struct highlander_i2c_dev *dev) { iowrite16(ioread16(dev->base + SMCR) | SMCR_IEIC, dev->base + SMCR); } static inline void highlander_i2c_irq_disable(struct highlander_i2c_dev *dev) { iowrite16(ioread16(dev->base + SMCR) & ~SMCR_IEIC, dev->base + SMCR); } static inline void highlander_i2c_start(struct highlander_i2c_dev *dev) { iowrite16(ioread16(dev->base + SMCR) | SMCR_START, dev->base + SMCR); } static inline void highlander_i2c_done(struct highlander_i2c_dev *dev) { iowrite16(ioread16(dev->base + SMCR) | SMCR_IRIC, dev->base + SMCR); } static void highlander_i2c_setup(struct highlander_i2c_dev *dev) { u16 smmr; smmr = ioread16(dev->base + SMMR); smmr |= SMMR_TMMD; if (iic_force_normal) smmr &= ~SMMR_SP; else smmr |= SMMR_SP; iowrite16(smmr, dev->base + SMMR); } static void smbus_write_data(u8 *src, u16 *dst, int len) { for (; len > 1; len -= 2) { *dst++ = be16_to_cpup((__be16 *)src); src += 2; } if (len) *dst = *src << 8; } static void smbus_read_data(u16 *src, u8 *dst, int len) { for (; len > 1; len -= 2) { *(__be16 *)dst = cpu_to_be16p(src++); dst += 2; } if (len) *dst = *src >> 8; } static void highlander_i2c_command(struct highlander_i2c_dev *dev, u8 command, int len) { unsigned int i; u16 cmd = (command << 8) | command; for (i = 0; i < len; i += 2) { if (len - i == 1) cmd = command << 8; iowrite16(cmd, dev->base + SMSADR + i); dev_dbg(dev->dev, "command data[%x] 0x%04x\n", i/2, cmd); } } static int highlander_i2c_wait_for_bbsy(struct highlander_i2c_dev *dev) { unsigned long timeout; timeout = jiffies + msecs_to_jiffies(iic_timeout); while (ioread16(dev->base + SMCR) & SMCR_BBSY) { if (time_after(jiffies, timeout)) { dev_warn(dev->dev, "timeout waiting for bus ready\n"); return -ETIMEDOUT; } msleep(1); } return 0; } static int highlander_i2c_reset(struct highlander_i2c_dev *dev) { iowrite16(ioread16(dev->base + SMCR) | SMCR_RST, dev->base + SMCR); return highlander_i2c_wait_for_bbsy(dev); } static int highlander_i2c_wait_for_ack(struct highlander_i2c_dev *dev) { u16 tmp = ioread16(dev->base + SMCR); if ((tmp & (SMCR_IRIC | SMCR_ACKE)) == SMCR_ACKE) { dev_warn(dev->dev, "ack abnormality\n"); return highlander_i2c_reset(dev); } return 0; } static irqreturn_t highlander_i2c_irq(int irq, void *dev_id) { struct highlander_i2c_dev *dev = dev_id; highlander_i2c_done(dev); complete(&dev->cmd_complete); return IRQ_HANDLED; } static void highlander_i2c_poll(struct highlander_i2c_dev *dev) { unsigned long timeout; u16 smcr; timeout = jiffies + msecs_to_jiffies(iic_timeout); for (;;) { smcr = ioread16(dev->base + SMCR); /* * Don't bother checking ACKE here, this and the reset * are handled in highlander_i2c_wait_xfer_done() when * waiting for the ACK. */ if (smcr & SMCR_IRIC) return; if (time_after(jiffies, timeout)) break; cpu_relax(); cond_resched(); } dev_err(dev->dev, "polling timed out\n"); } static inline int highlander_i2c_wait_xfer_done(struct highlander_i2c_dev *dev) { if (dev->irq) wait_for_completion_timeout(&dev->cmd_complete, msecs_to_jiffies(iic_timeout)); else /* busy looping, the IRQ of champions */ highlander_i2c_poll(dev); return highlander_i2c_wait_for_ack(dev); } static int highlander_i2c_read(struct highlander_i2c_dev *dev) { int i, cnt; u16 data[16]; if (highlander_i2c_wait_for_bbsy(dev)) return -EAGAIN; highlander_i2c_start(dev); if (highlander_i2c_wait_xfer_done(dev)) { dev_err(dev->dev, "Arbitration loss\n"); return -EAGAIN; } /* * The R0P7780LC0011RL FPGA needs a significant delay between * data read cycles, otherwise the transceiver gets confused and * garbage is returned when the read is subsequently aborted. * * It is not sufficient to wait for BBSY. * * While this generally only applies to the older SH7780-based * Highlanders, the same issue can be observed on SH7785 ones, * albeit less frequently. SH7780-based Highlanders may need * this to be as high as 1000 ms. */ if (iic_read_delay && time_before(jiffies, dev->last_read_time + msecs_to_jiffies(iic_read_delay))) msleep(jiffies_to_msecs((dev->last_read_time + msecs_to_jiffies(iic_read_delay)) - jiffies)); cnt = (dev->buf_len + 1) >> 1; for (i = 0; i < cnt; i++) { data[i] = ioread16(dev->base + SMTRDR + (i * sizeof(u16))); dev_dbg(dev->dev, "read data[%x] 0x%04x\n", i, data[i]); } smbus_read_data(data, dev->buf, dev->buf_len); dev->last_read_time = jiffies; return 0; } static int highlander_i2c_write(struct highlander_i2c_dev *dev) { int i, cnt; u16 data[16]; smbus_write_data(dev->buf, data, dev->buf_len); cnt = (dev->buf_len + 1) >> 1; for (i = 0; i < cnt; i++) { iowrite16(data[i], dev->base + SMTRDR + (i * sizeof(u16))); dev_dbg(dev->dev, "write data[%x] 0x%04x\n", i, data[i]); } if (highlander_i2c_wait_for_bbsy(dev)) return -EAGAIN; highlander_i2c_start(dev); return highlander_i2c_wait_xfer_done(dev); } static int highlander_i2c_smbus_xfer(struct i2c_adapter *adap, u16 addr, unsigned short flags, char read_write, u8 command, int size, union i2c_smbus_data *data) { struct highlander_i2c_dev *dev = i2c_get_adapdata(adap); u16 tmp; init_completion(&dev->cmd_complete); dev_dbg(dev->dev, "addr %04x, command %02x, read_write %d, size %d\n", addr, command, read_write, size); /* * Set up the buffer and transfer size */ switch (size) { case I2C_SMBUS_BYTE_DATA: dev->buf = &data->byte; dev->buf_len = 1; break; case I2C_SMBUS_I2C_BLOCK_DATA: dev->buf = &data->block[1]; dev->buf_len = data->block[0]; break; default: dev_err(dev->dev, "unsupported command %d\n", size); return -EINVAL; } /* * Encode the mode setting */ tmp = ioread16(dev->base + SMMR); tmp &= ~(SMMR_MODE0 | SMMR_MODE1); switch (dev->buf_len) { case 1: /* default */ break; case 8: tmp |= SMMR_MODE0; break; case 16: tmp |= SMMR_MODE1; break; case 32: tmp |= (SMMR_MODE0 | SMMR_MODE1); break; default: dev_err(dev->dev, "unsupported xfer size %zu\n", dev->buf_len); return -EINVAL; } iowrite16(tmp, dev->base + SMMR); /* Ensure we're in a sane state */ highlander_i2c_done(dev); /* Set slave address */ iowrite16((addr << 1) | read_write, dev->base + SMSMADR); highlander_i2c_command(dev, command, dev->buf_len); if (read_write == I2C_SMBUS_READ) return highlander_i2c_read(dev); else return highlander_i2c_write(dev); } static u32 highlander_i2c_func(struct i2c_adapter *adapter) { return I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_I2C_BLOCK; } static const struct i2c_algorithm highlander_i2c_algo = { .smbus_xfer = highlander_i2c_smbus_xfer, .functionality = highlander_i2c_func, }; static int highlander_i2c_probe(struct platform_device *pdev) { struct highlander_i2c_dev *dev; struct i2c_adapter *adap; struct resource *res; int ret; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (unlikely(!res)) { dev_err(&pdev->dev, "no mem resource\n"); return -ENODEV; } dev = kzalloc(sizeof(struct highlander_i2c_dev), GFP_KERNEL); if (unlikely(!dev)) return -ENOMEM; dev->base = ioremap(res->start, resource_size(res)); if (unlikely(!dev->base)) { ret = -ENXIO; goto err; } dev->dev = &pdev->dev; platform_set_drvdata(pdev, dev); dev->irq = platform_get_irq(pdev, 0); if (iic_force_poll) dev->irq = 0; if (dev->irq) { ret = request_irq(dev->irq, highlander_i2c_irq, 0, pdev->name, dev); if (unlikely(ret)) goto err_unmap; highlander_i2c_irq_enable(dev); } else { dev_notice(&pdev->dev, "no IRQ, using polling mode\n"); highlander_i2c_irq_disable(dev); } dev->last_read_time = jiffies; /* initial read jiffies */ highlander_i2c_setup(dev); adap = &dev->adapter; i2c_set_adapdata(adap, dev); adap->owner = THIS_MODULE; adap->class = I2C_CLASS_HWMON; strlcpy(adap->name, "HL FPGA I2C adapter", sizeof(adap->name)); adap->algo = &highlander_i2c_algo; adap->dev.parent = &pdev->dev; adap->nr = pdev->id; /* * Reset the adapter */ ret = highlander_i2c_reset(dev); if (unlikely(ret)) { dev_err(&pdev->dev, "controller didn't come up\n"); goto err_free_irq; } ret = i2c_add_numbered_adapter(adap); if (unlikely(ret)) { dev_err(&pdev->dev, "failure adding adapter\n"); goto err_free_irq; } return 0; err_free_irq: if (dev->irq) free_irq(dev->irq, dev); err_unmap: iounmap(dev->base); err: kfree(dev); return ret; } static int highlander_i2c_remove(struct platform_device *pdev) { struct highlander_i2c_dev *dev = platform_get_drvdata(pdev); i2c_del_adapter(&dev->adapter); if (dev->irq) free_irq(dev->irq, dev); iounmap(dev->base); kfree(dev); return 0; } static struct platform_driver highlander_i2c_driver = { .driver = { .name = "i2c-highlander", }, .probe = highlander_i2c_probe, .remove = highlander_i2c_remove, }; module_platform_driver(highlander_i2c_driver); MODULE_AUTHOR("Paul Mundt"); MODULE_DESCRIPTION("Renesas Highlander FPGA I2C/SMBus adapter"); MODULE_LICENSE("GPL v2"); module_param(iic_force_poll, bool, 0); module_param(iic_force_normal, bool, 0); module_param(iic_timeout, int, 0); module_param(iic_read_delay, int, 0); MODULE_PARM_DESC(iic_force_poll, "Force polling mode"); MODULE_PARM_DESC(iic_force_normal, "Force normal mode (100 kHz), default is fast mode (400 kHz)"); MODULE_PARM_DESC(iic_timeout, "Set timeout value in msecs (default 1000 ms)"); MODULE_PARM_DESC(iic_read_delay, "Delay between data read cycles (default 0 ms)");
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