// SPDX-License-Identifier: GPL-2.0-or-later /* * TI DAVINCI I2C adapter driver. * * Copyright (C) 2006 Texas Instruments. * Copyright (C) 2007 MontaVista Software Inc. * * Updated by Vinod & Sudhakar Feb 2005 * * ---------------------------------------------------------------------------- * * ---------------------------------------------------------------------------- */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* ----- global defines ----------------------------------------------- */ #define DAVINCI_I2C_TIMEOUT (1*HZ) #define DAVINCI_I2C_MAX_TRIES 2 #define DAVINCI_I2C_OWN_ADDRESS 0x08 #define I2C_DAVINCI_INTR_ALL (DAVINCI_I2C_IMR_SCD | \ DAVINCI_I2C_IMR_ARDY | \ DAVINCI_I2C_IMR_NACK | \ DAVINCI_I2C_IMR_AL) #define DAVINCI_I2C_OAR_REG 0x00 #define DAVINCI_I2C_IMR_REG 0x04 #define DAVINCI_I2C_STR_REG 0x08 #define DAVINCI_I2C_CLKL_REG 0x0c #define DAVINCI_I2C_CLKH_REG 0x10 #define DAVINCI_I2C_CNT_REG 0x14 #define DAVINCI_I2C_DRR_REG 0x18 #define DAVINCI_I2C_SAR_REG 0x1c #define DAVINCI_I2C_DXR_REG 0x20 #define DAVINCI_I2C_MDR_REG 0x24 #define DAVINCI_I2C_IVR_REG 0x28 #define DAVINCI_I2C_EMDR_REG 0x2c #define DAVINCI_I2C_PSC_REG 0x30 #define DAVINCI_I2C_FUNC_REG 0x48 #define DAVINCI_I2C_DIR_REG 0x4c #define DAVINCI_I2C_DIN_REG 0x50 #define DAVINCI_I2C_DOUT_REG 0x54 #define DAVINCI_I2C_DSET_REG 0x58 #define DAVINCI_I2C_DCLR_REG 0x5c #define DAVINCI_I2C_IVR_AAS 0x07 #define DAVINCI_I2C_IVR_SCD 0x06 #define DAVINCI_I2C_IVR_XRDY 0x05 #define DAVINCI_I2C_IVR_RDR 0x04 #define DAVINCI_I2C_IVR_ARDY 0x03 #define DAVINCI_I2C_IVR_NACK 0x02 #define DAVINCI_I2C_IVR_AL 0x01 #define DAVINCI_I2C_STR_BB BIT(12) #define DAVINCI_I2C_STR_RSFULL BIT(11) #define DAVINCI_I2C_STR_SCD BIT(5) #define DAVINCI_I2C_STR_ARDY BIT(2) #define DAVINCI_I2C_STR_NACK BIT(1) #define DAVINCI_I2C_STR_AL BIT(0) #define DAVINCI_I2C_MDR_NACK BIT(15) #define DAVINCI_I2C_MDR_STT BIT(13) #define DAVINCI_I2C_MDR_STP BIT(11) #define DAVINCI_I2C_MDR_MST BIT(10) #define DAVINCI_I2C_MDR_TRX BIT(9) #define DAVINCI_I2C_MDR_XA BIT(8) #define DAVINCI_I2C_MDR_RM BIT(7) #define DAVINCI_I2C_MDR_IRS BIT(5) #define DAVINCI_I2C_IMR_AAS BIT(6) #define DAVINCI_I2C_IMR_SCD BIT(5) #define DAVINCI_I2C_IMR_XRDY BIT(4) #define DAVINCI_I2C_IMR_RRDY BIT(3) #define DAVINCI_I2C_IMR_ARDY BIT(2) #define DAVINCI_I2C_IMR_NACK BIT(1) #define DAVINCI_I2C_IMR_AL BIT(0) /* set SDA and SCL as GPIO */ #define DAVINCI_I2C_FUNC_PFUNC0 BIT(0) /* set SCL as output when used as GPIO*/ #define DAVINCI_I2C_DIR_PDIR0 BIT(0) /* set SDA as output when used as GPIO*/ #define DAVINCI_I2C_DIR_PDIR1 BIT(1) /* read SCL GPIO level */ #define DAVINCI_I2C_DIN_PDIN0 BIT(0) /* read SDA GPIO level */ #define DAVINCI_I2C_DIN_PDIN1 BIT(1) /*set the SCL GPIO high */ #define DAVINCI_I2C_DSET_PDSET0 BIT(0) /*set the SDA GPIO high */ #define DAVINCI_I2C_DSET_PDSET1 BIT(1) /* set the SCL GPIO low */ #define DAVINCI_I2C_DCLR_PDCLR0 BIT(0) /* set the SDA GPIO low */ #define DAVINCI_I2C_DCLR_PDCLR1 BIT(1) /* timeout for pm runtime autosuspend */ #define DAVINCI_I2C_PM_TIMEOUT 1000 /* ms */ struct davinci_i2c_dev { struct device *dev; void __iomem *base; struct completion cmd_complete; struct clk *clk; int cmd_err; u8 *buf; size_t buf_len; int irq; int stop; u8 terminate; struct i2c_adapter adapter; #ifdef CONFIG_CPU_FREQ struct notifier_block freq_transition; #endif struct davinci_i2c_platform_data *pdata; }; /* default platform data to use if not supplied in the platform_device */ static struct davinci_i2c_platform_data davinci_i2c_platform_data_default = { .bus_freq = 100, .bus_delay = 0, }; static inline void davinci_i2c_write_reg(struct davinci_i2c_dev *i2c_dev, int reg, u16 val) { writew_relaxed(val, i2c_dev->base + reg); } static inline u16 davinci_i2c_read_reg(struct davinci_i2c_dev *i2c_dev, int reg) { return readw_relaxed(i2c_dev->base + reg); } static inline void davinci_i2c_reset_ctrl(struct davinci_i2c_dev *i2c_dev, int val) { u16 w; w = davinci_i2c_read_reg(i2c_dev, DAVINCI_I2C_MDR_REG); if (!val) /* put I2C into reset */ w &= ~DAVINCI_I2C_MDR_IRS; else /* take I2C out of reset */ w |= DAVINCI_I2C_MDR_IRS; davinci_i2c_write_reg(i2c_dev, DAVINCI_I2C_MDR_REG, w); } static void i2c_davinci_calc_clk_dividers(struct davinci_i2c_dev *dev) { struct davinci_i2c_platform_data *pdata = dev->pdata; u16 psc; u32 clk; u32 d; u32 clkh; u32 clkl; u32 input_clock = clk_get_rate(dev->clk); struct device_node *of_node = dev->dev->of_node; /* NOTE: I2C Clock divider programming info * As per I2C specs the following formulas provide prescaler * and low/high divider values * input clk --> PSC Div -----------> ICCL/H Div --> output clock * module clk * * output clk = module clk / (PSC + 1) [ (ICCL + d) + (ICCH + d) ] * * Thus, * (ICCL + ICCH) = clk = (input clk / ((psc +1) * output clk)) - 2d; * * where if PSC == 0, d = 7, * if PSC == 1, d = 6 * if PSC > 1 , d = 5 * * Note: * d is always 6 on Keystone I2C controller */ /* * Both Davinci and current Keystone User Guides recommend a value * between 7MHz and 12MHz. In reality 7MHz module clock doesn't * always produce enough margin between SDA and SCL transitions. * Measurements show that the higher the module clock is, the * bigger is the margin, providing more reliable communication. * So we better target for 12MHz. */ psc = (input_clock / 12000000) - 1; if ((input_clock / (psc + 1)) > 12000000) psc++; /* better to run under spec than over */ d = (psc >= 2) ? 5 : 7 - psc; if (of_node && of_device_is_compatible(of_node, "ti,keystone-i2c")) d = 6; clk = ((input_clock / (psc + 1)) / (pdata->bus_freq * 1000)); /* Avoid driving the bus too fast because of rounding errors above */ if (input_clock / (psc + 1) / clk > pdata->bus_freq * 1000) clk++; /* * According to I2C-BUS Spec 2.1, in FAST-MODE LOW period should be at * least 1.3uS, which is not the case with 50% duty cycle. Driving HIGH * to LOW ratio as 1 to 2 is more safe. */ if (pdata->bus_freq > 100) clkl = (clk << 1) / 3; else clkl = (clk >> 1); /* * It's not always possible to have 1 to 2 ratio when d=7, so fall back * to minimal possible clkh in this case. * * Note: * CLKH is not allowed to be 0, in this case I2C clock is not generated * at all */ if (clk > clkl + d) { clkh = clk - clkl - d; clkl -= d; } else { clkh = 1; clkl = clk - (d << 1); } davinci_i2c_write_reg(dev, DAVINCI_I2C_PSC_REG, psc); davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKH_REG, clkh); davinci_i2c_write_reg(dev, DAVINCI_I2C_CLKL_REG, clkl); dev_dbg(dev->dev, "input_clock = %d, CLK = %d\n", input_clock, clk); } /* * This function configures I2C and brings I2C out of reset. * This function is called during I2C init function. This function * also gets called if I2C encounters any errors. */ static int i2c_davinci_init(struct davinci_i2c_dev *dev) { struct davinci_i2c_platform_data *pdata = dev->pdata; /* put I2C into reset */ davinci_i2c_reset_ctrl(dev, 0); /* compute clock dividers */ i2c_davinci_calc_clk_dividers(dev); /* Respond at reserved "SMBus Host" slave address" (and zero); * we seem to have no option to not respond... */ davinci_i2c_write_reg(dev, DAVINCI_I2C_OAR_REG, DAVINCI_I2C_OWN_ADDRESS); dev_dbg(dev->dev, "PSC = %d\n", davinci_i2c_read_reg(dev, DAVINCI_I2C_PSC_REG)); dev_dbg(dev->dev, "CLKL = %d\n", davinci_i2c_read_reg(dev, DAVINCI_I2C_CLKL_REG)); dev_dbg(dev->dev, "CLKH = %d\n", davinci_i2c_read_reg(dev, DAVINCI_I2C_CLKH_REG)); dev_dbg(dev->dev, "bus_freq = %dkHz, bus_delay = %d\n", pdata->bus_freq, pdata->bus_delay); /* Take the I2C module out of reset: */ davinci_i2c_reset_ctrl(dev, 1); /* Enable interrupts */ davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, I2C_DAVINCI_INTR_ALL); return 0; } /* * This routine does i2c bus recovery by using i2c_generic_scl_recovery * which is provided by I2C Bus recovery infrastructure. */ static void davinci_i2c_prepare_recovery(struct i2c_adapter *adap) { struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); /* Disable interrupts */ davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, 0); /* put I2C into reset */ davinci_i2c_reset_ctrl(dev, 0); } static void davinci_i2c_unprepare_recovery(struct i2c_adapter *adap) { struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); i2c_davinci_init(dev); } static struct i2c_bus_recovery_info davinci_i2c_gpio_recovery_info = { .recover_bus = i2c_generic_scl_recovery, .prepare_recovery = davinci_i2c_prepare_recovery, .unprepare_recovery = davinci_i2c_unprepare_recovery, }; static void davinci_i2c_set_scl(struct i2c_adapter *adap, int val) { struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); if (val) davinci_i2c_write_reg(dev, DAVINCI_I2C_DSET_REG, DAVINCI_I2C_DSET_PDSET0); else davinci_i2c_write_reg(dev, DAVINCI_I2C_DCLR_REG, DAVINCI_I2C_DCLR_PDCLR0); } static int davinci_i2c_get_scl(struct i2c_adapter *adap) { struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); int val; /* read the state of SCL */ val = davinci_i2c_read_reg(dev, DAVINCI_I2C_DIN_REG); return val & DAVINCI_I2C_DIN_PDIN0; } static int davinci_i2c_get_sda(struct i2c_adapter *adap) { struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); int val; /* read the state of SDA */ val = davinci_i2c_read_reg(dev, DAVINCI_I2C_DIN_REG); return val & DAVINCI_I2C_DIN_PDIN1; } static void davinci_i2c_scl_prepare_recovery(struct i2c_adapter *adap) { struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); davinci_i2c_prepare_recovery(adap); /* SCL output, SDA input */ davinci_i2c_write_reg(dev, DAVINCI_I2C_DIR_REG, DAVINCI_I2C_DIR_PDIR0); /* change to GPIO mode */ davinci_i2c_write_reg(dev, DAVINCI_I2C_FUNC_REG, DAVINCI_I2C_FUNC_PFUNC0); } static void davinci_i2c_scl_unprepare_recovery(struct i2c_adapter *adap) { struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); /* change back to I2C mode */ davinci_i2c_write_reg(dev, DAVINCI_I2C_FUNC_REG, 0); davinci_i2c_unprepare_recovery(adap); } static struct i2c_bus_recovery_info davinci_i2c_scl_recovery_info = { .recover_bus = i2c_generic_scl_recovery, .set_scl = davinci_i2c_set_scl, .get_scl = davinci_i2c_get_scl, .get_sda = davinci_i2c_get_sda, .prepare_recovery = davinci_i2c_scl_prepare_recovery, .unprepare_recovery = davinci_i2c_scl_unprepare_recovery, }; /* * Waiting for bus not busy */ static int i2c_davinci_wait_bus_not_busy(struct davinci_i2c_dev *dev) { unsigned long timeout = jiffies + dev->adapter.timeout; do { if (!(davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG) & DAVINCI_I2C_STR_BB)) return 0; schedule_timeout_uninterruptible(1); } while (time_before_eq(jiffies, timeout)); dev_warn(dev->dev, "timeout waiting for bus ready\n"); i2c_recover_bus(&dev->adapter); /* * if bus is still "busy" here, it's most probably a HW problem like * short-circuit */ if (davinci_i2c_read_reg(dev, DAVINCI_I2C_STR_REG) & DAVINCI_I2C_STR_BB) return -EIO; return 0; } /* * Low level master read/write transaction. This function is called * from i2c_davinci_xfer. */ static int i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg, int stop) { struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); struct davinci_i2c_platform_data *pdata = dev->pdata; u32 flag; u16 w; unsigned long time_left; if (msg->addr == DAVINCI_I2C_OWN_ADDRESS) { dev_warn(dev->dev, "transfer to own address aborted\n"); return -EADDRNOTAVAIL; } /* Introduce a delay, required for some boards (e.g Davinci EVM) */ if (pdata->bus_delay) udelay(pdata->bus_delay); /* set the slave address */ davinci_i2c_write_reg(dev, DAVINCI_I2C_SAR_REG, msg->addr); dev->buf = msg->buf; dev->buf_len = msg->len; dev->stop = stop; davinci_i2c_write_reg(dev, DAVINCI_I2C_CNT_REG, dev->buf_len); reinit_completion(&dev->cmd_complete); dev->cmd_err = 0; /* Take I2C out of reset and configure it as master */ flag = DAVINCI_I2C_MDR_IRS | DAVINCI_I2C_MDR_MST; /* if the slave address is ten bit address, enable XA bit */ if (msg->flags & I2C_M_TEN) flag |= DAVINCI_I2C_MDR_XA; if (!(msg->flags & I2C_M_RD)) flag |= DAVINCI_I2C_MDR_TRX; if (msg->len == 0) flag |= DAVINCI_I2C_MDR_RM; /* Enable receive or transmit interrupts */ w = davinci_i2c_read_reg(dev, DAVINCI_I2C_IMR_REG); if (msg->flags & I2C_M_RD) w |= DAVINCI_I2C_IMR_RRDY; else w |= DAVINCI_I2C_IMR_XRDY; davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, w); dev->terminate = 0; /* * Write mode register first as needed for correct behaviour * on OMAP-L138, but don't set STT yet to avoid a race with XRDY * occurring before we have loaded DXR */ davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); /* * First byte should be set here, not after interrupt, * because transmit-data-ready interrupt can come before * NACK-interrupt during sending of previous message and * ICDXR may have wrong data * It also saves us one interrupt, slightly faster */ if ((!(msg->flags & I2C_M_RD)) && dev->buf_len) { davinci_i2c_write_reg(dev, DAVINCI_I2C_DXR_REG, *dev->buf++); dev->buf_len--; } /* Set STT to begin transmit now DXR is loaded */ flag |= DAVINCI_I2C_MDR_STT; if (stop && msg->len != 0) flag |= DAVINCI_I2C_MDR_STP; davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); time_left = wait_for_completion_timeout(&dev->cmd_complete, dev->adapter.timeout); if (!time_left) { dev_err(dev->dev, "controller timed out\n"); i2c_recover_bus(adap); dev->buf_len = 0; return -ETIMEDOUT; } if (dev->buf_len) { /* This should be 0 if all bytes were transferred * or dev->cmd_err denotes an error. */ dev_err(dev->dev, "abnormal termination buf_len=%zu\n", dev->buf_len); dev->terminate = 1; wmb(); dev->buf_len = 0; return -EREMOTEIO; } /* no error */ if (likely(!dev->cmd_err)) return msg->len; /* We have an error */ if (dev->cmd_err & DAVINCI_I2C_STR_AL) { i2c_davinci_init(dev); return -EIO; } if (dev->cmd_err & DAVINCI_I2C_STR_NACK) { if (msg->flags & I2C_M_IGNORE_NAK) return msg->len; w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); w |= DAVINCI_I2C_MDR_STP; davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); return -EREMOTEIO; } return -EIO; } /* * Prepare controller for a transaction and call i2c_davinci_xfer_msg */ static int i2c_davinci_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) { struct davinci_i2c_dev *dev = i2c_get_adapdata(adap); int i; int ret; dev_dbg(dev->dev, "%s: msgs: %d\n", __func__, num); ret = pm_runtime_resume_and_get(dev->dev); if (ret < 0) { dev_err(dev->dev, "Failed to runtime_get device: %d\n", ret); return ret; } ret = i2c_davinci_wait_bus_not_busy(dev); if (ret < 0) { dev_warn(dev->dev, "timeout waiting for bus ready\n"); goto out; } for (i = 0; i < num; i++) { ret = i2c_davinci_xfer_msg(adap, &msgs[i], (i == (num - 1))); dev_dbg(dev->dev, "%s [%d/%d] ret: %d\n", __func__, i + 1, num, ret); if (ret < 0) goto out; } ret = num; out: pm_runtime_mark_last_busy(dev->dev); pm_runtime_put_autosuspend(dev->dev); return ret; } static u32 i2c_davinci_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; } static void terminate_read(struct davinci_i2c_dev *dev) { u16 w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); w |= DAVINCI_I2C_MDR_NACK; davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); /* Throw away data */ davinci_i2c_read_reg(dev, DAVINCI_I2C_DRR_REG); if (!dev->terminate) dev_err(dev->dev, "RDR IRQ while no data requested\n"); } static void terminate_write(struct davinci_i2c_dev *dev) { u16 w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); w |= DAVINCI_I2C_MDR_RM | DAVINCI_I2C_MDR_STP; davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); if (!dev->terminate) dev_dbg(dev->dev, "TDR IRQ while no data to send\n"); } /* * Interrupt service routine. This gets called whenever an I2C interrupt * occurs. */ static irqreturn_t i2c_davinci_isr(int this_irq, void *dev_id) { struct davinci_i2c_dev *dev = dev_id; u32 stat; int count = 0; u16 w; if (pm_runtime_suspended(dev->dev)) return IRQ_NONE; while ((stat = davinci_i2c_read_reg(dev, DAVINCI_I2C_IVR_REG))) { dev_dbg(dev->dev, "%s: stat=0x%x\n", __func__, stat); if (count++ == 100) { dev_warn(dev->dev, "Too much work in one IRQ\n"); break; } switch (stat) { case DAVINCI_I2C_IVR_AL: /* Arbitration lost, must retry */ dev->cmd_err |= DAVINCI_I2C_STR_AL; dev->buf_len = 0; complete(&dev->cmd_complete); break; case DAVINCI_I2C_IVR_NACK: dev->cmd_err |= DAVINCI_I2C_STR_NACK; dev->buf_len = 0; complete(&dev->cmd_complete); break; case DAVINCI_I2C_IVR_ARDY: davinci_i2c_write_reg(dev, DAVINCI_I2C_STR_REG, DAVINCI_I2C_STR_ARDY); if (((dev->buf_len == 0) && (dev->stop != 0)) || (dev->cmd_err & DAVINCI_I2C_STR_NACK)) { w = davinci_i2c_read_reg(dev, DAVINCI_I2C_MDR_REG); w |= DAVINCI_I2C_MDR_STP; davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, w); } complete(&dev->cmd_complete); break; case DAVINCI_I2C_IVR_RDR: if (dev->buf_len) { *dev->buf++ = davinci_i2c_read_reg(dev, DAVINCI_I2C_DRR_REG); dev->buf_len--; if (dev->buf_len) continue; davinci_i2c_write_reg(dev, DAVINCI_I2C_STR_REG, DAVINCI_I2C_IMR_RRDY); } else { /* signal can terminate transfer */ terminate_read(dev); } break; case DAVINCI_I2C_IVR_XRDY: if (dev->buf_len) { davinci_i2c_write_reg(dev, DAVINCI_I2C_DXR_REG, *dev->buf++); dev->buf_len--; if (dev->buf_len) continue; w = davinci_i2c_read_reg(dev, DAVINCI_I2C_IMR_REG); w &= ~DAVINCI_I2C_IMR_XRDY; davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, w); } else { /* signal can terminate transfer */ terminate_write(dev); } break; case DAVINCI_I2C_IVR_SCD: davinci_i2c_write_reg(dev, DAVINCI_I2C_STR_REG, DAVINCI_I2C_STR_SCD); complete(&dev->cmd_complete); break; case DAVINCI_I2C_IVR_AAS: dev_dbg(dev->dev, "Address as slave interrupt\n"); break; default: dev_warn(dev->dev, "Unrecognized irq stat %d\n", stat); break; } } return count ? IRQ_HANDLED : IRQ_NONE; } #ifdef CONFIG_CPU_FREQ static int i2c_davinci_cpufreq_transition(struct notifier_block *nb, unsigned long val, void *data) { struct davinci_i2c_dev *dev; dev = container_of(nb, struct davinci_i2c_dev, freq_transition); i2c_lock_bus(&dev->adapter, I2C_LOCK_ROOT_ADAPTER); if (val == CPUFREQ_PRECHANGE) { davinci_i2c_reset_ctrl(dev, 0); } else if (val == CPUFREQ_POSTCHANGE) { i2c_davinci_calc_clk_dividers(dev); davinci_i2c_reset_ctrl(dev, 1); } i2c_unlock_bus(&dev->adapter, I2C_LOCK_ROOT_ADAPTER); return 0; } static inline int i2c_davinci_cpufreq_register(struct davinci_i2c_dev *dev) { dev->freq_transition.notifier_call = i2c_davinci_cpufreq_transition; return cpufreq_register_notifier(&dev->freq_transition, CPUFREQ_TRANSITION_NOTIFIER); } static inline void i2c_davinci_cpufreq_deregister(struct davinci_i2c_dev *dev) { cpufreq_unregister_notifier(&dev->freq_transition, CPUFREQ_TRANSITION_NOTIFIER); } #else static inline int i2c_davinci_cpufreq_register(struct davinci_i2c_dev *dev) { return 0; } static inline void i2c_davinci_cpufreq_deregister(struct davinci_i2c_dev *dev) { } #endif static const struct i2c_algorithm i2c_davinci_algo = { .master_xfer = i2c_davinci_xfer, .functionality = i2c_davinci_func, }; static const struct of_device_id davinci_i2c_of_match[] = { {.compatible = "ti,davinci-i2c", }, {.compatible = "ti,keystone-i2c", }, {}, }; MODULE_DEVICE_TABLE(of, davinci_i2c_of_match); static int davinci_i2c_probe(struct platform_device *pdev) { struct davinci_i2c_dev *dev; struct i2c_adapter *adap; struct i2c_bus_recovery_info *rinfo; int r, irq; irq = platform_get_irq(pdev, 0); if (irq < 0) return dev_err_probe(&pdev->dev, irq, "can't get irq resource\n"); dev = devm_kzalloc(&pdev->dev, sizeof(struct davinci_i2c_dev), GFP_KERNEL); if (!dev) { dev_err(&pdev->dev, "Memory allocation failed\n"); return -ENOMEM; } init_completion(&dev->cmd_complete); dev->dev = &pdev->dev; dev->irq = irq; dev->pdata = dev_get_platdata(&pdev->dev); platform_set_drvdata(pdev, dev); if (!dev->pdata && pdev->dev.of_node) { u32 prop; dev->pdata = devm_kzalloc(&pdev->dev, sizeof(struct davinci_i2c_platform_data), GFP_KERNEL); if (!dev->pdata) return -ENOMEM; memcpy(dev->pdata, &davinci_i2c_platform_data_default, sizeof(struct davinci_i2c_platform_data)); if (!of_property_read_u32(pdev->dev.of_node, "clock-frequency", &prop)) dev->pdata->bus_freq = prop / 1000; dev->pdata->has_pfunc = of_property_read_bool(pdev->dev.of_node, "ti,has-pfunc"); } else if (!dev->pdata) { dev->pdata = &davinci_i2c_platform_data_default; } dev->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(dev->clk)) return PTR_ERR(dev->clk); dev->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(dev->base)) { return PTR_ERR(dev->base); } pm_runtime_set_autosuspend_delay(dev->dev, DAVINCI_I2C_PM_TIMEOUT); pm_runtime_use_autosuspend(dev->dev); pm_runtime_enable(dev->dev); r = pm_runtime_resume_and_get(dev->dev); if (r < 0) { dev_err(dev->dev, "failed to runtime_get device: %d\n", r); goto err_pm; } i2c_davinci_init(dev); r = devm_request_irq(&pdev->dev, dev->irq, i2c_davinci_isr, 0, pdev->name, dev); if (r) { dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq); goto err_unuse_clocks; } r = i2c_davinci_cpufreq_register(dev); if (r) { dev_err(&pdev->dev, "failed to register cpufreq\n"); goto err_unuse_clocks; } adap = &dev->adapter; i2c_set_adapdata(adap, dev); adap->owner = THIS_MODULE; adap->class = I2C_CLASS_DEPRECATED; strscpy(adap->name, "DaVinci I2C adapter", sizeof(adap->name)); adap->algo = &i2c_davinci_algo; adap->dev.parent = &pdev->dev; adap->timeout = DAVINCI_I2C_TIMEOUT; adap->dev.of_node = pdev->dev.of_node; if (dev->pdata->has_pfunc) adap->bus_recovery_info = &davinci_i2c_scl_recovery_info; else if (dev->pdata->gpio_recovery) { rinfo = &davinci_i2c_gpio_recovery_info; adap->bus_recovery_info = rinfo; rinfo->scl_gpiod = devm_gpiod_get(&pdev->dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN); if (IS_ERR(rinfo->scl_gpiod)) { r = PTR_ERR(rinfo->scl_gpiod); goto err_unuse_clocks; } rinfo->sda_gpiod = devm_gpiod_get(&pdev->dev, "sda", GPIOD_IN); if (IS_ERR(rinfo->sda_gpiod)) { r = PTR_ERR(rinfo->sda_gpiod); goto err_unuse_clocks; } } adap->nr = pdev->id; r = i2c_add_numbered_adapter(adap); if (r) goto err_unuse_clocks; pm_runtime_mark_last_busy(dev->dev); pm_runtime_put_autosuspend(dev->dev); return 0; err_unuse_clocks: pm_runtime_dont_use_autosuspend(dev->dev); pm_runtime_put_sync(dev->dev); err_pm: pm_runtime_disable(dev->dev); return r; } static int davinci_i2c_remove(struct platform_device *pdev) { struct davinci_i2c_dev *dev = platform_get_drvdata(pdev); int ret; i2c_davinci_cpufreq_deregister(dev); i2c_del_adapter(&dev->adapter); ret = pm_runtime_resume_and_get(&pdev->dev); if (ret < 0) return ret; davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, 0); pm_runtime_dont_use_autosuspend(dev->dev); pm_runtime_put_sync(dev->dev); pm_runtime_disable(dev->dev); return 0; } #ifdef CONFIG_PM static int davinci_i2c_suspend(struct device *dev) { struct davinci_i2c_dev *i2c_dev = dev_get_drvdata(dev); /* put I2C into reset */ davinci_i2c_reset_ctrl(i2c_dev, 0); return 0; } static int davinci_i2c_resume(struct device *dev) { struct davinci_i2c_dev *i2c_dev = dev_get_drvdata(dev); /* take I2C out of reset */ davinci_i2c_reset_ctrl(i2c_dev, 1); return 0; } static const struct dev_pm_ops davinci_i2c_pm = { .suspend = davinci_i2c_suspend, .resume = davinci_i2c_resume, SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, pm_runtime_force_resume) }; #define davinci_i2c_pm_ops (&davinci_i2c_pm) #else #define davinci_i2c_pm_ops NULL #endif /* work with hotplug and coldplug */ MODULE_ALIAS("platform:i2c_davinci"); static struct platform_driver davinci_i2c_driver = { .probe = davinci_i2c_probe, .remove = davinci_i2c_remove, .driver = { .name = "i2c_davinci", .pm = davinci_i2c_pm_ops, .of_match_table = davinci_i2c_of_match, }, }; /* I2C may be needed to bring up other drivers */ static int __init davinci_i2c_init_driver(void) { return platform_driver_register(&davinci_i2c_driver); } subsys_initcall(davinci_i2c_init_driver); static void __exit davinci_i2c_exit_driver(void) { platform_driver_unregister(&davinci_i2c_driver); } module_exit(davinci_i2c_exit_driver); MODULE_AUTHOR("Texas Instruments India"); MODULE_DESCRIPTION("TI DaVinci I2C bus adapter"); MODULE_LICENSE("GPL");