1 // SPDX-License-Identifier: GPL-2.0
3  * Synopsys DesignWare I2C adapter driver (slave only).
5  * Based on the Synopsys DesignWare I2C adapter driver (master).
15 #include <linux/i2c.h>
22 #include "i2c-designware-core.h"
27 	regmap_write(dev->map, DW_IC_TX_TL, 0);  in i2c_dw_configure_fifo_slave()
28 	regmap_write(dev->map, DW_IC_RX_TL, 0);  in i2c_dw_configure_fifo_slave()
30 	/* Configure the I2C slave. */  in i2c_dw_configure_fifo_slave()
31 	regmap_write(dev->map, DW_IC_CON, dev->slave_cfg);  in i2c_dw_configure_fifo_slave()
32 	regmap_write(dev->map, DW_IC_INTR_MASK, DW_IC_INTR_SLAVE_MASK);  in i2c_dw_configure_fifo_slave()
36  * i2c_dw_init_slave() - Initialize the DesignWare i2c slave hardware
39  * This function configures and enables the I2C in slave mode.
40  * This function is called during I2C init function, and in case of timeout at
57 	if (dev->sda_hold_time)  in i2c_dw_init_slave()
58 		regmap_write(dev->map, DW_IC_SDA_HOLD, dev->sda_hold_time);  in i2c_dw_init_slave()
68 	struct dw_i2c_dev *dev = i2c_get_adapdata(slave->adapter);  in i2c_dw_reg_slave()
70 	if (dev->slave)  in i2c_dw_reg_slave()
71 		return -EBUSY;  in i2c_dw_reg_slave()
72 	if (slave->flags & I2C_CLIENT_TEN)  in i2c_dw_reg_slave()
73 		return -EAFNOSUPPORT;  in i2c_dw_reg_slave()
74 	pm_runtime_get_sync(dev->dev);  in i2c_dw_reg_slave()
81 	regmap_write(dev->map, DW_IC_SAR, slave->addr);  in i2c_dw_reg_slave()
82 	dev->slave = slave;  in i2c_dw_reg_slave()
86 	dev->status = 0;  in i2c_dw_reg_slave()
93 	struct dw_i2c_dev *dev = i2c_get_adapdata(slave->adapter);  in i2c_dw_unreg_slave()
95 	regmap_write(dev->map, DW_IC_INTR_MASK, 0);  in i2c_dw_unreg_slave()
97 	synchronize_irq(dev->irq);  in i2c_dw_unreg_slave()
98 	dev->slave = NULL;  in i2c_dw_unreg_slave()
99 	pm_runtime_put(dev->dev);  in i2c_dw_unreg_slave()
120 	regmap_read(dev->map, DW_IC_INTR_STAT, &stat);  in i2c_dw_read_clear_intrbits_slave()
127 	 * Instead, use the separately-prepared IC_CLR_* registers.  in i2c_dw_read_clear_intrbits_slave()
130 		regmap_read(dev->map, DW_IC_CLR_TX_ABRT, &dummy);  in i2c_dw_read_clear_intrbits_slave()
132 		regmap_read(dev->map, DW_IC_CLR_RX_UNDER, &dummy);  in i2c_dw_read_clear_intrbits_slave()
134 		regmap_read(dev->map, DW_IC_CLR_RX_OVER, &dummy);  in i2c_dw_read_clear_intrbits_slave()
136 		regmap_read(dev->map, DW_IC_CLR_TX_OVER, &dummy);  in i2c_dw_read_clear_intrbits_slave()
138 		regmap_read(dev->map, DW_IC_CLR_RX_DONE, &dummy);  in i2c_dw_read_clear_intrbits_slave()
140 		regmap_read(dev->map, DW_IC_CLR_ACTIVITY, &dummy);  in i2c_dw_read_clear_intrbits_slave()
142 		regmap_read(dev->map, DW_IC_CLR_STOP_DET, &dummy);  in i2c_dw_read_clear_intrbits_slave()
144 		regmap_read(dev->map, DW_IC_CLR_START_DET, &dummy);  in i2c_dw_read_clear_intrbits_slave()
146 		regmap_read(dev->map, DW_IC_CLR_GEN_CALL, &dummy);  in i2c_dw_read_clear_intrbits_slave()
152  * Interrupt service routine. This gets called whenever an I2C slave interrupt
161 	regmap_read(dev->map, DW_IC_ENABLE, &enabled);  in i2c_dw_isr_slave()
162 	regmap_read(dev->map, DW_IC_RAW_INTR_STAT, &raw_stat);  in i2c_dw_isr_slave()
163 	regmap_read(dev->map, DW_IC_STATUS, &tmp);  in i2c_dw_isr_slave()
166 	if (!enabled || !(raw_stat & ~DW_IC_INTR_ACTIVITY) || !dev->slave)  in i2c_dw_isr_slave()
170 	dev_dbg(dev->dev,  in i2c_dw_isr_slave()
175 		if (!(dev->status & STATUS_WRITE_IN_PROGRESS)) {  in i2c_dw_isr_slave()
176 			dev->status |= STATUS_WRITE_IN_PROGRESS;  in i2c_dw_isr_slave()
177 			dev->status &= ~STATUS_READ_IN_PROGRESS;  in i2c_dw_isr_slave()
178 			i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_REQUESTED,  in i2c_dw_isr_slave()
183 			regmap_read(dev->map, DW_IC_DATA_CMD, &tmp);  in i2c_dw_isr_slave()
185 				i2c_slave_event(dev->slave,  in i2c_dw_isr_slave()
189 			i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_RECEIVED,  in i2c_dw_isr_slave()
191 			regmap_read(dev->map, DW_IC_STATUS, &tmp);  in i2c_dw_isr_slave()
197 			regmap_read(dev->map, DW_IC_CLR_RD_REQ, &tmp);  in i2c_dw_isr_slave()
199 			if (!(dev->status & STATUS_READ_IN_PROGRESS)) {  in i2c_dw_isr_slave()
200 				i2c_slave_event(dev->slave,  in i2c_dw_isr_slave()
203 				dev->status |= STATUS_READ_IN_PROGRESS;  in i2c_dw_isr_slave()
204 				dev->status &= ~STATUS_WRITE_IN_PROGRESS;  in i2c_dw_isr_slave()
206 				i2c_slave_event(dev->slave,  in i2c_dw_isr_slave()
210 			regmap_write(dev->map, DW_IC_DATA_CMD, val);  in i2c_dw_isr_slave()
215 		i2c_slave_event(dev->slave, I2C_SLAVE_STOP, &val);  in i2c_dw_isr_slave()
228 	dev->functionality = I2C_FUNC_SLAVE;  in i2c_dw_configure_slave()
230 	dev->slave_cfg = DW_IC_CON_RX_FIFO_FULL_HLD_CTRL |  in i2c_dw_configure_slave()
233 	dev->mode = DW_IC_SLAVE;  in i2c_dw_configure_slave()
239 	struct i2c_adapter *adap = &dev->adapter;  in i2c_dw_probe_slave()
242 	dev->init = i2c_dw_init_slave;  in i2c_dw_probe_slave()
256 	ret = dev->init(dev);  in i2c_dw_probe_slave()
260 	snprintf(adap->name, sizeof(adap->name),  in i2c_dw_probe_slave()
261 		 "Synopsys DesignWare I2C Slave adapter");  in i2c_dw_probe_slave()
262 	adap->retries = 3;  in i2c_dw_probe_slave()
263 	adap->algo = &i2c_dw_algo;  in i2c_dw_probe_slave()
264 	adap->dev.parent = dev->dev;  in i2c_dw_probe_slave()
267 	ret = devm_request_irq(dev->dev, dev->irq, i2c_dw_isr_slave,  in i2c_dw_probe_slave()
268 			       IRQF_SHARED, dev_name(dev->dev), dev);  in i2c_dw_probe_slave()
270 		dev_err(dev->dev, "failure requesting IRQ %i: %d\n",  in i2c_dw_probe_slave()
271 			dev->irq, ret);  in i2c_dw_probe_slave()
277 		dev_err(dev->dev, "failure adding adapter: %d\n", ret);  in i2c_dw_probe_slave()
284 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus slave adapter");