16 #include <linux/i2c.h>
68 	complete(&priv->comp);  in uniphier_i2c_interrupt()
80 	reinit_completion(&priv->comp);  in uniphier_i2c_xfer_byte()
83 	dev_dbg(&adap->dev, "write data: 0x%04x\n", txdata);  in uniphier_i2c_xfer_byte()
84 	writel(txdata, priv->membase + UNIPHIER_I2C_DTRM);  in uniphier_i2c_xfer_byte()
86 	time_left = wait_for_completion_timeout(&priv->comp, adap->timeout);  in uniphier_i2c_xfer_byte()
88 		dev_err(&adap->dev, "transaction timeout\n");  in uniphier_i2c_xfer_byte()
89 		return -ETIMEDOUT;  in uniphier_i2c_xfer_byte()
92 	rxdata = readl(priv->membase + UNIPHIER_I2C_DREC);  in uniphier_i2c_xfer_byte()
93 	dev_dbg(&adap->dev, "read data: 0x%04x\n", rxdata);  in uniphier_i2c_xfer_byte()
111 		dev_dbg(&adap->dev, "arbitration lost\n");  in uniphier_i2c_send_byte()
112 		return -EAGAIN;  in uniphier_i2c_send_byte()
115 		dev_dbg(&adap->dev, "could not get ACK\n");  in uniphier_i2c_send_byte()
116 		return -ENXIO;  in uniphier_i2c_send_byte()
127 	dev_dbg(&adap->dev, "start condition\n");  in uniphier_i2c_tx()
134 	while (len--) {  in uniphier_i2c_tx()
149 	dev_dbg(&adap->dev, "start condition\n");  in uniphier_i2c_rx()
157 	while (len--) {  in uniphier_i2c_rx()
173 	dev_dbg(&adap->dev, "stop condition\n");  in uniphier_i2c_stop()
181 	bool is_read = msg->flags & I2C_M_RD;  in uniphier_i2c_master_xfer_one()
185 	dev_dbg(&adap->dev, "%s: addr=0x%02x, len=%d, stop=%d\n",  in uniphier_i2c_master_xfer_one()
186 		is_read ? "receive" : "transmit", msg->addr, msg->len, stop);  in uniphier_i2c_master_xfer_one()
189 		ret = uniphier_i2c_rx(adap, msg->addr, msg->len, msg->buf);  in uniphier_i2c_master_xfer_one()
191 		ret = uniphier_i2c_tx(adap, msg->addr, msg->len, msg->buf);  in uniphier_i2c_master_xfer_one()
193 	if (ret == -EAGAIN) /* could not acquire bus. bail out without STOP */  in uniphier_i2c_master_xfer_one()
196 	if (ret == -ETIMEDOUT) {  in uniphier_i2c_master_xfer_one()
222 	if (!(readl(priv->membase + UNIPHIER_I2C_DREC) &  in uniphier_i2c_check_bus_busy()
224 		if (priv->busy_cnt++ > 3) {  in uniphier_i2c_check_bus_busy()
230 			priv->busy_cnt = 0;  in uniphier_i2c_check_bus_busy()
233 		return -EAGAIN;  in uniphier_i2c_check_bus_busy()
236 	priv->busy_cnt = 0;  in uniphier_i2c_check_bus_busy()
252 		bool stop = (msg + 1 == emsg) || (msg->flags & I2C_M_STOP);  in uniphier_i2c_master_xfer()
277 	writel(val, priv->membase + UNIPHIER_I2C_BRST);  in uniphier_i2c_reset()
284 	return !!(readl(priv->membase + UNIPHIER_I2C_BSTS) &  in uniphier_i2c_get_scl()
293 	       priv->membase + UNIPHIER_I2C_BRST);  in uniphier_i2c_set_scl()
300 	return !!(readl(priv->membase + UNIPHIER_I2C_BSTS) &  in uniphier_i2c_get_sda()
319 	unsigned int cyc = priv->clk_cycle;  in uniphier_i2c_hw_init()
324 	 * Bit30-16: clock cycles of tLOW.  in uniphier_i2c_hw_init()
325 	 *  Standard-mode: tLOW = 4.7 us, tHIGH = 4.0 us  in uniphier_i2c_hw_init()
326 	 *  Fast-mode:     tLOW = 1.3 us, tHIGH = 0.6 us  in uniphier_i2c_hw_init()
329 	writel((cyc * 5 / 9 << 16) | cyc, priv->membase + UNIPHIER_I2C_CLK);  in uniphier_i2c_hw_init()
336 	struct device *dev = &pdev->dev;  in uniphier_i2c_probe()
345 		return -ENOMEM;  in uniphier_i2c_probe()
348 	priv->membase = devm_ioremap_resource(dev, regs);  in uniphier_i2c_probe()
349 	if (IS_ERR(priv->membase))  in uniphier_i2c_probe()
350 		return PTR_ERR(priv->membase);  in uniphier_i2c_probe()
358 	if (of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed))  in uniphier_i2c_probe()
362 		dev_err(dev, "invalid clock-frequency %d\n", bus_speed);  in uniphier_i2c_probe()
363 		return -EINVAL;  in uniphier_i2c_probe()
366 	priv->clk = devm_clk_get(dev, NULL);  in uniphier_i2c_probe()
367 	if (IS_ERR(priv->clk)) {  in uniphier_i2c_probe()
369 		return PTR_ERR(priv->clk);  in uniphier_i2c_probe()
372 	ret = clk_prepare_enable(priv->clk);  in uniphier_i2c_probe()
376 	clk_rate = clk_get_rate(priv->clk);  in uniphier_i2c_probe()
379 		ret = -EINVAL;  in uniphier_i2c_probe()
383 	priv->clk_cycle = clk_rate / bus_speed;  in uniphier_i2c_probe()
384 	init_completion(&priv->comp);  in uniphier_i2c_probe()
385 	priv->adap.owner = THIS_MODULE;  in uniphier_i2c_probe()
386 	priv->adap.algo = &uniphier_i2c_algo;  in uniphier_i2c_probe()
387 	priv->adap.dev.parent = dev;  in uniphier_i2c_probe()
388 	priv->adap.dev.of_node = dev->of_node;  in uniphier_i2c_probe()
389 	strlcpy(priv->adap.name, "UniPhier I2C", sizeof(priv->adap.name));  in uniphier_i2c_probe()
390 	priv->adap.bus_recovery_info = &uniphier_i2c_bus_recovery_info;  in uniphier_i2c_probe()
391 	i2c_set_adapdata(&priv->adap, priv);  in uniphier_i2c_probe()
396 	ret = devm_request_irq(dev, irq, uniphier_i2c_interrupt, 0, pdev->name,  in uniphier_i2c_probe()
403 	ret = i2c_add_adapter(&priv->adap);  in uniphier_i2c_probe()
406 		clk_disable_unprepare(priv->clk);  in uniphier_i2c_probe()
415 	i2c_del_adapter(&priv->adap);  in uniphier_i2c_remove()
416 	clk_disable_unprepare(priv->clk);  in uniphier_i2c_remove()
425 	clk_disable_unprepare(priv->clk);  in uniphier_i2c_suspend()
435 	ret = clk_prepare_enable(priv->clk);  in uniphier_i2c_resume()
449 	{ .compatible = "socionext,uniphier-i2c" },
458 		.name  = "uniphier-i2c",
466 MODULE_DESCRIPTION("UniPhier I2C bus driver");