diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-slave.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-slave.c | 202 |
1 files changed, 98 insertions, 104 deletions
diff --git a/drivers/i2c/busses/i2c-designware-slave.c b/drivers/i2c/busses/i2c-designware-slave.c index e7f9305b2dd9..6eb16b7d75a6 100644 --- a/drivers/i2c/busses/i2c-designware-slave.c +++ b/drivers/i2c/busses/i2c-designware-slave.c @@ -6,6 +6,9 @@ * * Copyright (C) 2016 Synopsys Inc. */ + +#define DEFAULT_SYMBOL_NAMESPACE "I2C_DW" + #include <linux/delay.h> #include <linux/err.h> #include <linux/errno.h> @@ -14,27 +17,30 @@ #include <linux/io.h> #include <linux/module.h> #include <linux/pm_runtime.h> +#include <linux/regmap.h> #include "i2c-designware-core.h" static void i2c_dw_configure_fifo_slave(struct dw_i2c_dev *dev) { /* Configure Tx/Rx FIFO threshold levels. */ - dw_writel(dev, 0, DW_IC_TX_TL); - dw_writel(dev, 0, DW_IC_RX_TL); + regmap_write(dev->map, DW_IC_TX_TL, 0); + regmap_write(dev->map, DW_IC_RX_TL, 0); /* Configure the I2C slave. */ - dw_writel(dev, dev->slave_cfg, DW_IC_CON); - dw_writel(dev, DW_IC_INTR_SLAVE_MASK, DW_IC_INTR_MASK); + regmap_write(dev->map, DW_IC_CON, dev->slave_cfg); + regmap_write(dev->map, DW_IC_INTR_MASK, DW_IC_INTR_SLAVE_MASK); } /** - * i2c_dw_init_slave() - Initialize the designware i2c slave hardware + * i2c_dw_init_slave() - Initialize the DesignWare i2c slave hardware * @dev: device private data * * This function configures and enables the I2C in slave mode. * This function is called during I2C init function, and in case of timeout at * run time. + * + * Return: 0 on success, or negative errno otherwise. */ static int i2c_dw_init_slave(struct dw_i2c_dev *dev) { @@ -49,7 +55,7 @@ static int i2c_dw_init_slave(struct dw_i2c_dev *dev) /* Write SDA hold time if supported */ if (dev->sda_hold_time) - dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD); + regmap_write(dev->map, DW_IC_SDA_HOLD, dev->sda_hold_time); i2c_dw_configure_fifo_slave(dev); i2c_dw_release_lock(dev); @@ -72,18 +78,12 @@ static int i2c_dw_reg_slave(struct i2c_client *slave) * the address to which the DW_apb_i2c responds. */ __i2c_dw_disable_nowait(dev); - dw_writel(dev, slave->addr, DW_IC_SAR); + regmap_write(dev->map, DW_IC_SAR, slave->addr); dev->slave = slave; __i2c_dw_enable(dev); - dev->cmd_err = 0; - dev->msg_write_idx = 0; - dev->msg_read_idx = 0; - dev->msg_err = 0; - dev->status = STATUS_IDLE; - dev->abort_source = 0; - dev->rx_outstanding = 0; + dev->status = 0; return 0; } @@ -92,57 +92,58 @@ static int i2c_dw_unreg_slave(struct i2c_client *slave) { struct dw_i2c_dev *dev = i2c_get_adapdata(slave->adapter); - dev->disable_int(dev); - dev->disable(dev); + regmap_write(dev->map, DW_IC_INTR_MASK, 0); + i2c_dw_disable(dev); + synchronize_irq(dev->irq); dev->slave = NULL; - pm_runtime_put(dev->dev); + pm_runtime_put_sync_suspend(dev->dev); return 0; } static u32 i2c_dw_read_clear_intrbits_slave(struct dw_i2c_dev *dev) { - u32 stat; + unsigned int stat, dummy; /* * The IC_INTR_STAT register just indicates "enabled" interrupts. - * Ths unmasked raw version of interrupt status bits are available + * The unmasked raw version of interrupt status bits is available * in the IC_RAW_INTR_STAT register. * * That is, - * stat = dw_readl(IC_INTR_STAT); + * stat = readl(IC_INTR_STAT); * equals to, - * stat = dw_readl(IC_RAW_INTR_STAT) & dw_readl(IC_INTR_MASK); + * stat = readl(IC_RAW_INTR_STAT) & readl(IC_INTR_MASK); * * The raw version might be useful for debugging purposes. */ - stat = dw_readl(dev, DW_IC_INTR_STAT); + regmap_read(dev->map, DW_IC_INTR_STAT, &stat); /* * Do not use the IC_CLR_INTR register to clear interrupts, or * you'll miss some interrupts, triggered during the period from - * dw_readl(IC_INTR_STAT) to dw_readl(IC_CLR_INTR). + * readl(IC_INTR_STAT) to readl(IC_CLR_INTR). * * Instead, use the separately-prepared IC_CLR_* registers. */ if (stat & DW_IC_INTR_TX_ABRT) - dw_readl(dev, DW_IC_CLR_TX_ABRT); + regmap_read(dev->map, DW_IC_CLR_TX_ABRT, &dummy); if (stat & DW_IC_INTR_RX_UNDER) - dw_readl(dev, DW_IC_CLR_RX_UNDER); + regmap_read(dev->map, DW_IC_CLR_RX_UNDER, &dummy); if (stat & DW_IC_INTR_RX_OVER) - dw_readl(dev, DW_IC_CLR_RX_OVER); + regmap_read(dev->map, DW_IC_CLR_RX_OVER, &dummy); if (stat & DW_IC_INTR_TX_OVER) - dw_readl(dev, DW_IC_CLR_TX_OVER); + regmap_read(dev->map, DW_IC_CLR_TX_OVER, &dummy); if (stat & DW_IC_INTR_RX_DONE) - dw_readl(dev, DW_IC_CLR_RX_DONE); + regmap_read(dev->map, DW_IC_CLR_RX_DONE, &dummy); if (stat & DW_IC_INTR_ACTIVITY) - dw_readl(dev, DW_IC_CLR_ACTIVITY); + regmap_read(dev->map, DW_IC_CLR_ACTIVITY, &dummy); if (stat & DW_IC_INTR_STOP_DET) - dw_readl(dev, DW_IC_CLR_STOP_DET); + regmap_read(dev->map, DW_IC_CLR_STOP_DET, &dummy); if (stat & DW_IC_INTR_START_DET) - dw_readl(dev, DW_IC_CLR_START_DET); + regmap_read(dev->map, DW_IC_CLR_START_DET, &dummy); if (stat & DW_IC_INTR_GEN_CALL) - dw_readl(dev, DW_IC_CLR_GEN_CALL); + regmap_read(dev->map, DW_IC_CLR_GEN_CALL, &dummy); return stat; } @@ -151,87 +152,69 @@ static u32 i2c_dw_read_clear_intrbits_slave(struct dw_i2c_dev *dev) * Interrupt service routine. This gets called whenever an I2C slave interrupt * occurs. */ - -static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev) +static irqreturn_t i2c_dw_isr_slave(int this_irq, void *dev_id) { - u32 raw_stat, stat, enabled; - u8 val, slave_activity; + struct dw_i2c_dev *dev = dev_id; + unsigned int raw_stat, stat, enabled, tmp; + u8 val = 0, slave_activity; - stat = dw_readl(dev, DW_IC_INTR_STAT); - enabled = dw_readl(dev, DW_IC_ENABLE); - raw_stat = dw_readl(dev, DW_IC_RAW_INTR_STAT); - slave_activity = ((dw_readl(dev, DW_IC_STATUS) & - DW_IC_STATUS_SLAVE_ACTIVITY) >> 6); + regmap_read(dev->map, DW_IC_ENABLE, &enabled); + regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &raw_stat); + regmap_read(dev->map, DW_IC_STATUS, &tmp); + slave_activity = ((tmp & DW_IC_STATUS_SLAVE_ACTIVITY) >> 6); if (!enabled || !(raw_stat & ~DW_IC_INTR_ACTIVITY) || !dev->slave) - return 0; + return IRQ_NONE; + stat = i2c_dw_read_clear_intrbits_slave(dev); dev_dbg(dev->dev, "%#x STATUS SLAVE_ACTIVITY=%#x : RAW_INTR_STAT=%#x : INTR_STAT=%#x\n", enabled, slave_activity, raw_stat, stat); - if ((stat & DW_IC_INTR_RX_FULL) && (stat & DW_IC_INTR_STOP_DET)) - i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_REQUESTED, &val); + if (stat & DW_IC_INTR_RX_FULL) { + if (!(dev->status & STATUS_WRITE_IN_PROGRESS)) { + dev->status |= STATUS_WRITE_IN_PROGRESS; + dev->status &= ~STATUS_READ_IN_PROGRESS; + i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_REQUESTED, + &val); + } + + do { + regmap_read(dev->map, DW_IC_DATA_CMD, &tmp); + if (tmp & DW_IC_DATA_CMD_FIRST_DATA_BYTE) + i2c_slave_event(dev->slave, + I2C_SLAVE_WRITE_REQUESTED, + &val); + val = tmp; + i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_RECEIVED, + &val); + regmap_read(dev->map, DW_IC_STATUS, &tmp); + } while (tmp & DW_IC_STATUS_RFNE); + } if (stat & DW_IC_INTR_RD_REQ) { if (slave_activity) { - if (stat & DW_IC_INTR_RX_FULL) { - val = dw_readl(dev, DW_IC_DATA_CMD); - - if (!i2c_slave_event(dev->slave, - I2C_SLAVE_WRITE_RECEIVED, - &val)) { - dev_vdbg(dev->dev, "Byte %X acked!", - val); - } - dw_readl(dev, DW_IC_CLR_RD_REQ); - stat = i2c_dw_read_clear_intrbits_slave(dev); + regmap_read(dev->map, DW_IC_CLR_RD_REQ, &tmp); + + if (!(dev->status & STATUS_READ_IN_PROGRESS)) { + i2c_slave_event(dev->slave, + I2C_SLAVE_READ_REQUESTED, + &val); + dev->status |= STATUS_READ_IN_PROGRESS; + dev->status &= ~STATUS_WRITE_IN_PROGRESS; } else { - dw_readl(dev, DW_IC_CLR_RD_REQ); - dw_readl(dev, DW_IC_CLR_RX_UNDER); - stat = i2c_dw_read_clear_intrbits_slave(dev); + i2c_slave_event(dev->slave, + I2C_SLAVE_READ_PROCESSED, + &val); } - if (!i2c_slave_event(dev->slave, - I2C_SLAVE_READ_REQUESTED, - &val)) - dw_writel(dev, val, DW_IC_DATA_CMD); + regmap_write(dev->map, DW_IC_DATA_CMD, val); } } - if (stat & DW_IC_INTR_RX_DONE) { - if (!i2c_slave_event(dev->slave, I2C_SLAVE_READ_PROCESSED, - &val)) - dw_readl(dev, DW_IC_CLR_RX_DONE); - - i2c_slave_event(dev->slave, I2C_SLAVE_STOP, &val); - stat = i2c_dw_read_clear_intrbits_slave(dev); - return 1; - } - - if (stat & DW_IC_INTR_RX_FULL) { - val = dw_readl(dev, DW_IC_DATA_CMD); - if (!i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_RECEIVED, - &val)) - dev_vdbg(dev->dev, "Byte %X acked!", val); - } else { + if (stat & DW_IC_INTR_STOP_DET) i2c_slave_event(dev->slave, I2C_SLAVE_STOP, &val); - stat = i2c_dw_read_clear_intrbits_slave(dev); - } - return 1; -} - -static irqreturn_t i2c_dw_isr_slave(int this_irq, void *dev_id) -{ - struct dw_i2c_dev *dev = dev_id; - int ret; - - i2c_dw_read_clear_intrbits_slave(dev); - ret = i2c_dw_irq_handler_slave(dev); - if (ret > 0) - complete(&dev->cmd_complete); - - return IRQ_RETVAL(ret); + return IRQ_HANDLED; } static const struct i2c_algorithm i2c_dw_algo = { @@ -240,18 +223,25 @@ static const struct i2c_algorithm i2c_dw_algo = { .unreg_slave = i2c_dw_unreg_slave, }; +void i2c_dw_configure_slave(struct dw_i2c_dev *dev) +{ + dev->functionality = I2C_FUNC_SLAVE; + + dev->slave_cfg = DW_IC_CON_RX_FIFO_FULL_HLD_CTRL | + DW_IC_CON_RESTART_EN | DW_IC_CON_STOP_DET_IFADDRESSED; + + dev->mode = DW_IC_SLAVE; +} +EXPORT_SYMBOL_GPL(i2c_dw_configure_slave); + int i2c_dw_probe_slave(struct dw_i2c_dev *dev) { struct i2c_adapter *adap = &dev->adapter; int ret; - init_completion(&dev->cmd_complete); - dev->init = i2c_dw_init_slave; - dev->disable = i2c_dw_disable; - dev->disable_int = i2c_dw_disable_int; - ret = i2c_dw_set_reg_access(dev); + ret = i2c_dw_init_regmap(dev); if (ret) return ret; @@ -259,6 +249,10 @@ int i2c_dw_probe_slave(struct dw_i2c_dev *dev) if (ret) return ret; + ret = i2c_dw_set_fifo_size(dev); + if (ret) + return ret; + ret = dev->init(dev); if (ret) return ret; @@ -272,11 +266,10 @@ int i2c_dw_probe_slave(struct dw_i2c_dev *dev) ret = devm_request_irq(dev->dev, dev->irq, i2c_dw_isr_slave, IRQF_SHARED, dev_name(dev->dev), dev); - if (ret) { - dev_err(dev->dev, "failure requesting irq %i: %d\n", - dev->irq, ret); - return ret; - } + if (ret) + return dev_err_probe(dev->dev, ret, + "failure requesting IRQ %i: %d\n", + dev->irq, ret); ret = i2c_add_numbered_adapter(adap); if (ret) @@ -289,3 +282,4 @@ EXPORT_SYMBOL_GPL(i2c_dw_probe_slave); MODULE_AUTHOR("Luis Oliveira <lolivei@synopsys.com>"); MODULE_DESCRIPTION("Synopsys DesignWare I2C bus slave adapter"); MODULE_LICENSE("GPL v2"); +MODULE_IMPORT_NS("I2C_DW_COMMON"); |
