1 // SPDX-License-Identifier: GPL-2.0+
4  * Copyright (C) 2015-2016 Socionext Inc.
23 	u32 dttx;			/* send FIFO (write-only) */
24 #define dtrx		dttx		/* receive FIFO (read-only) */
74 	writel(I2C_RST_RST, &priv->regs->rst);  in uniphier_fi2c_reset()
82 	ret = readl_poll_timeout(&priv->regs->sr, val, !(val & I2C_SR_DB), 100);  in uniphier_fi2c_check_bus_busy()
84 		dev_dbg(priv->dev, "error: device busy too long. reset...\n");  in uniphier_fi2c_check_bus_busy()
98 		return -EINVAL;  in uniphier_fi2c_probe()
100 	priv->regs = devm_ioremap(dev, addr, SZ_128);  in uniphier_fi2c_probe()
101 	if (!priv->regs)  in uniphier_fi2c_probe()
102 		return -ENOMEM;  in uniphier_fi2c_probe()
104 	priv->fioclk = FIOCLK;  in uniphier_fi2c_probe()
106 	priv->dev = dev;  in uniphier_fi2c_probe()
111 	writel(I2C_BRST_FOEN | I2C_BRST_RSCLO, &priv->regs->brst);  in uniphier_fi2c_probe()
122 	ret = readl_poll_timeout(&priv->regs->intr, irq, irq & flags,  in wait_for_irq()
123 				 priv->timeout);  in wait_for_irq()
125 		dev_dbg(priv->dev, "error: time out\n");  in wait_for_irq()
130 		dev_dbg(priv->dev, "error: arbitration lost\n");  in wait_for_irq()
136 		dev_dbg(priv->dev, "error: no answer\n");  in wait_for_irq()
147 	dev_dbg(priv->dev, "stop condition\n");  in issue_stop()
148 	writel(I2C_CR_MST | I2C_CR_STO, &priv->regs->cr);  in issue_stop()
152 		dev_dbg(priv->dev, "error: device busy after operation\n");  in issue_stop()
162 	struct uniphier_fi2c_regs __iomem *regs = priv->regs;  in uniphier_fi2c_transmit()
164 	dev_dbg(priv->dev, "%s: addr = %x, len = %d\n", __func__, addr, len);  in uniphier_fi2c_transmit()
166 	writel(I2C_DTTX_CMD | addr << 1, &regs->dttx);  in uniphier_fi2c_transmit()
168 	writel(irq_flags, &regs->ie);  in uniphier_fi2c_transmit()
169 	writel(irq_flags, &regs->ic);  in uniphier_fi2c_transmit()
171 	dev_dbg(priv->dev, "start condition\n");  in uniphier_fi2c_transmit()
172 	writel(I2C_CR_MST | I2C_CR_STA, &regs->cr);  in uniphier_fi2c_transmit()
178 	while (len--) {  in uniphier_fi2c_transmit()
179 		dev_dbg(priv->dev, "sending %x\n", *buf);  in uniphier_fi2c_transmit()
180 		writel(*buf++, &regs->dttx);  in uniphier_fi2c_transmit()
182 		writel(irq_flags, &regs->ic);  in uniphier_fi2c_transmit()
190 	writel(irq_flags, &regs->ic);  in uniphier_fi2c_transmit()
203 	struct uniphier_fi2c_regs __iomem *regs = priv->regs;  in uniphier_fi2c_receive()
205 	dev_dbg(priv->dev, "%s: addr = %x, len = %d\n", __func__, addr, len);  in uniphier_fi2c_receive()
214 	writel(I2C_DTTX_CMD | I2C_DTTX_RD | addr << 1, &regs->dttx);  in uniphier_fi2c_receive()
216 	writel(0, &regs->rbc);  in uniphier_fi2c_receive()
217 	writel(irq_flags, &regs->ie);  in uniphier_fi2c_receive()
218 	writel(irq_flags, &regs->ic);  in uniphier_fi2c_receive()
220 	dev_dbg(priv->dev, "start condition\n");  in uniphier_fi2c_receive()
222 	       &regs->cr);  in uniphier_fi2c_receive()
224 	while (len--) {  in uniphier_fi2c_receive()
229 		*buf++ = readl(&regs->dtrx);  in uniphier_fi2c_receive()
230 		dev_dbg(priv->dev, "received %x\n", *(buf - 1));  in uniphier_fi2c_receive()
233 			writel(I2C_CR_MST | I2C_CR_NACK, &regs->cr);  in uniphier_fi2c_receive()
235 		writel(irq_flags, &regs->ic);  in uniphier_fi2c_receive()
239 	writel(irq_flags, &regs->ic);  in uniphier_fi2c_receive()
258 	for (; nmsgs > 0; nmsgs--, msg++) {  in uniphier_fi2c_xfer()
262 		if (msg->flags & I2C_M_RD)  in uniphier_fi2c_xfer()
263 			ret = uniphier_fi2c_receive(priv, msg->addr, msg->len,  in uniphier_fi2c_xfer()
264 						    msg->buf, &stop);  in uniphier_fi2c_xfer()
266 			ret = uniphier_fi2c_transmit(priv, msg->addr, msg->len,  in uniphier_fi2c_xfer()
267 						     msg->buf, &stop);  in uniphier_fi2c_xfer()
281 	struct uniphier_fi2c_regs __iomem *regs = priv->regs;  in uniphier_fi2c_set_bus_speed()
285 		return -EINVAL;  in uniphier_fi2c_set_bus_speed()
292 	writel(I2C_BRST_RSCLO, &regs->brst);  in uniphier_fi2c_set_bus_speed()
294 	clk_count = priv->fioclk / speed;  in uniphier_fi2c_set_bus_speed()
296 	writel(clk_count, &regs->cyc);  in uniphier_fi2c_set_bus_speed()
297 	writel(clk_count / 2, &regs->lctl);  in uniphier_fi2c_set_bus_speed()
298 	writel(clk_count / 2, &regs->ssut);  in uniphier_fi2c_set_bus_speed()
299 	writel(clk_count / 16, &regs->dsut);  in uniphier_fi2c_set_bus_speed()
301 	writel(I2C_BRST_FOEN | I2C_BRST_RSCLO, &regs->brst);  in uniphier_fi2c_set_bus_speed()
308 	priv->timeout = 100000000L / speed;  in uniphier_fi2c_set_bus_speed()
319 	{ .compatible = "socionext,uniphier-fi2c" },
324 	.name = "uniphier-fi2c",