3  * Driver for I2C adapter in Rockchip RK3xxx SoC
11 #include <linux/i2c.h>
162  * @grf_offset: offset inside the grf regmap for setting the i2c type
163  * @calc_timings: Callback function for i2c timing information calculated
173  * @adap: corresponding I2C adapter
179  * @clk_rate_nb: i2c clk rate change notify
180  * @t: I2C known timing information
181  * @lock: spinlock for the i2c bus
182  * @wait: the waitqueue to wait for i2c transfer
184  * @msg: current i2c message
185  * @addr: addr of i2c slave device
186  * @mode: mode of i2c transfer
188  * @state: state of i2c transfer
190  * @error: error code for i2c transfer
217 	/* I2C state machine */
223 static inline void i2c_writel(struct rk3x_i2c *i2c, u32 value,  in i2c_writel()  argument
226 	writel(value, i2c->regs + offset);  in i2c_writel()
229 static inline u32 i2c_readl(struct rk3x_i2c *i2c, unsigned int offset)  in i2c_readl()  argument
231 	return readl(i2c->regs + offset);  in i2c_readl()
235 static inline void rk3x_i2c_clean_ipd(struct rk3x_i2c *i2c)  in rk3x_i2c_clean_ipd()  argument
237 	i2c_writel(i2c, REG_INT_ALL, REG_IPD);  in rk3x_i2c_clean_ipd()
243 static void rk3x_i2c_start(struct rk3x_i2c *i2c)  in rk3x_i2c_start()  argument
245 	u32 val = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK;  in rk3x_i2c_start()
247 	i2c_writel(i2c, REG_INT_START, REG_IEN);  in rk3x_i2c_start()
250 	val |= REG_CON_EN | REG_CON_MOD(i2c->mode) | REG_CON_START;  in rk3x_i2c_start()
253 	if (!(i2c->msg->flags & I2C_M_IGNORE_NAK))  in rk3x_i2c_start()
256 	i2c_writel(i2c, val, REG_CON);  in rk3x_i2c_start()
264 static void rk3x_i2c_stop(struct rk3x_i2c *i2c, int error)  in rk3x_i2c_stop()  argument
268 	i2c->processed = 0;  in rk3x_i2c_stop()
269 	i2c->msg = NULL;  in rk3x_i2c_stop()
270 	i2c->error = error;  in rk3x_i2c_stop()
272 	if (i2c->is_last_msg) {  in rk3x_i2c_stop()
274 		i2c_writel(i2c, REG_INT_STOP, REG_IEN);  in rk3x_i2c_stop()
276 		i2c->state = STATE_STOP;  in rk3x_i2c_stop()
278 		ctrl = i2c_readl(i2c, REG_CON);  in rk3x_i2c_stop()
280 		i2c_writel(i2c, ctrl, REG_CON);  in rk3x_i2c_stop()
283 		i2c->busy = false;  in rk3x_i2c_stop()
284 		i2c->state = STATE_IDLE;  in rk3x_i2c_stop()
291 		ctrl = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK;  in rk3x_i2c_stop()
292 		i2c_writel(i2c, ctrl, REG_CON);  in rk3x_i2c_stop()
295 		wake_up(&i2c->wait);  in rk3x_i2c_stop()
300  * Setup a read according to i2c->msg
302 static void rk3x_i2c_prepare_read(struct rk3x_i2c *i2c)  in rk3x_i2c_prepare_read()  argument
304 	unsigned int len = i2c->msg->len - i2c->processed;  in rk3x_i2c_prepare_read()
307 	con = i2c_readl(i2c, REG_CON);  in rk3x_i2c_prepare_read()
321 	if (i2c->processed != 0) {  in rk3x_i2c_prepare_read()
326 	i2c_writel(i2c, con, REG_CON);  in rk3x_i2c_prepare_read()
327 	i2c_writel(i2c, len, REG_MRXCNT);  in rk3x_i2c_prepare_read()
331  * Fill the transmit buffer with data from i2c->msg
333 static void rk3x_i2c_fill_transmit_buf(struct rk3x_i2c *i2c)  in rk3x_i2c_fill_transmit_buf()  argument
343 			if ((i2c->processed == i2c->msg->len) && (cnt != 0))  in rk3x_i2c_fill_transmit_buf()
346 			if (i2c->processed == 0 && cnt == 0)  in rk3x_i2c_fill_transmit_buf()
347 				byte = (i2c->addr & 0x7f) << 1;  in rk3x_i2c_fill_transmit_buf()
349 				byte = i2c->msg->buf[i2c->processed++];  in rk3x_i2c_fill_transmit_buf()
355 		i2c_writel(i2c, val, TXBUFFER_BASE + 4 * i);  in rk3x_i2c_fill_transmit_buf()
357 		if (i2c->processed == i2c->msg->len)  in rk3x_i2c_fill_transmit_buf()
361 	i2c_writel(i2c, cnt, REG_MTXCNT);  in rk3x_i2c_fill_transmit_buf()
367 static void rk3x_i2c_handle_start(struct rk3x_i2c *i2c, unsigned int ipd)  in rk3x_i2c_handle_start()  argument
370 		rk3x_i2c_stop(i2c, -EIO);  in rk3x_i2c_handle_start()
371 		dev_warn(i2c->dev, "unexpected irq in START: 0x%x\n", ipd);  in rk3x_i2c_handle_start()
372 		rk3x_i2c_clean_ipd(i2c);  in rk3x_i2c_handle_start()
377 	i2c_writel(i2c, REG_INT_START, REG_IPD);  in rk3x_i2c_handle_start()
380 	i2c_writel(i2c, i2c_readl(i2c, REG_CON) & ~REG_CON_START, REG_CON);  in rk3x_i2c_handle_start()
383 	if (i2c->mode == REG_CON_MOD_TX) {  in rk3x_i2c_handle_start()
384 		i2c_writel(i2c, REG_INT_MBTF | REG_INT_NAKRCV, REG_IEN);  in rk3x_i2c_handle_start()
385 		i2c->state = STATE_WRITE;  in rk3x_i2c_handle_start()
386 		rk3x_i2c_fill_transmit_buf(i2c);  in rk3x_i2c_handle_start()
389 		i2c_writel(i2c, REG_INT_MBRF | REG_INT_NAKRCV, REG_IEN);  in rk3x_i2c_handle_start()
390 		i2c->state = STATE_READ;  in rk3x_i2c_handle_start()
391 		rk3x_i2c_prepare_read(i2c);  in rk3x_i2c_handle_start()
395 static void rk3x_i2c_handle_write(struct rk3x_i2c *i2c, unsigned int ipd)  in rk3x_i2c_handle_write()  argument
398 		rk3x_i2c_stop(i2c, -EIO);  in rk3x_i2c_handle_write()
399 		dev_err(i2c->dev, "unexpected irq in WRITE: 0x%x\n", ipd);  in rk3x_i2c_handle_write()
400 		rk3x_i2c_clean_ipd(i2c);  in rk3x_i2c_handle_write()
405 	i2c_writel(i2c, REG_INT_MBTF, REG_IPD);  in rk3x_i2c_handle_write()
408 	if (i2c->processed == i2c->msg->len)  in rk3x_i2c_handle_write()
409 		rk3x_i2c_stop(i2c, i2c->error);  in rk3x_i2c_handle_write()
411 		rk3x_i2c_fill_transmit_buf(i2c);  in rk3x_i2c_handle_write()
414 static void rk3x_i2c_handle_read(struct rk3x_i2c *i2c, unsigned int ipd)  in rk3x_i2c_handle_read()  argument
417 	unsigned int len = i2c->msg->len - i2c->processed;  in rk3x_i2c_handle_read()
426 	i2c_writel(i2c, REG_INT_MBRF, REG_IPD);  in rk3x_i2c_handle_read()
435 			val = i2c_readl(i2c, RXBUFFER_BASE + (i / 4) * 4);  in rk3x_i2c_handle_read()
438 		i2c->msg->buf[i2c->processed++] = byte;  in rk3x_i2c_handle_read()
442 	if (i2c->processed == i2c->msg->len)  in rk3x_i2c_handle_read()
443 		rk3x_i2c_stop(i2c, i2c->error);  in rk3x_i2c_handle_read()
445 		rk3x_i2c_prepare_read(i2c);  in rk3x_i2c_handle_read()
448 static void rk3x_i2c_handle_stop(struct rk3x_i2c *i2c, unsigned int ipd)  in rk3x_i2c_handle_stop()  argument
453 		rk3x_i2c_stop(i2c, -EIO);  in rk3x_i2c_handle_stop()
454 		dev_err(i2c->dev, "unexpected irq in STOP: 0x%x\n", ipd);  in rk3x_i2c_handle_stop()
455 		rk3x_i2c_clean_ipd(i2c);  in rk3x_i2c_handle_stop()
460 	i2c_writel(i2c, REG_INT_STOP, REG_IPD);  in rk3x_i2c_handle_stop()
463 	con = i2c_readl(i2c, REG_CON);  in rk3x_i2c_handle_stop()
465 	i2c_writel(i2c, con, REG_CON);  in rk3x_i2c_handle_stop()
467 	i2c->busy = false;  in rk3x_i2c_handle_stop()
468 	i2c->state = STATE_IDLE;  in rk3x_i2c_handle_stop()
471 	wake_up(&i2c->wait);  in rk3x_i2c_handle_stop()
476 	struct rk3x_i2c *i2c = dev_id;  in rk3x_i2c_irq()  local
479 	spin_lock(&i2c->lock);  in rk3x_i2c_irq()
481 	ipd = i2c_readl(i2c, REG_IPD);  in rk3x_i2c_irq()
482 	if (i2c->state == STATE_IDLE) {  in rk3x_i2c_irq()
483 		dev_warn(i2c->dev, "irq in STATE_IDLE, ipd = 0x%x\n", ipd);  in rk3x_i2c_irq()
484 		rk3x_i2c_clean_ipd(i2c);  in rk3x_i2c_irq()
488 	dev_dbg(i2c->dev, "IRQ: state %d, ipd: %x\n", i2c->state, ipd);  in rk3x_i2c_irq()
499 		i2c_writel(i2c, REG_INT_NAKRCV, REG_IPD);  in rk3x_i2c_irq()
503 		if (!(i2c->msg->flags & I2C_M_IGNORE_NAK))  in rk3x_i2c_irq()
504 			rk3x_i2c_stop(i2c, -ENXIO);  in rk3x_i2c_irq()
511 	switch (i2c->state) {  in rk3x_i2c_irq()
513 		rk3x_i2c_handle_start(i2c, ipd);  in rk3x_i2c_irq()
516 		rk3x_i2c_handle_write(i2c, ipd);  in rk3x_i2c_irq()
519 		rk3x_i2c_handle_read(i2c, ipd);  in rk3x_i2c_irq()
522 		rk3x_i2c_handle_stop(i2c, ipd);  in rk3x_i2c_irq()
529 	spin_unlock(&i2c->lock);  in rk3x_i2c_irq()
534  * Get timing values of I2C specification
538  * Returns: Matched i2c spec values.
553  * @clk_rate: I2C input clock rate
554  * @t: Known I2C timing information
590 	 *		meet I2C specification, should include fall time.  in rk3x_i2c_v0_calc_timings()
592 	 *		meet I2C specification, should include rise time.  in rk3x_i2c_v0_calc_timings()
594 	 *		I2C specification.  in rk3x_i2c_v0_calc_timings()
597 	 *	 This is because the i2c host on Rockchip holds the data line  in rk3x_i2c_v0_calc_timings()
714  * @clk_rate: I2C input clock rate
715  * @t: Known I2C timing information
770 	 *	       meet I2C specification, should include fall time.  in rk3x_i2c_v1_calc_timings()
772 	 *	        meet I2C specification, should include rise time.  in rk3x_i2c_v1_calc_timings()
789 	 * hardware would not output the i2c clk.  in rk3x_i2c_v1_calc_timings()
871 static void rk3x_i2c_adapt_div(struct rk3x_i2c *i2c, unsigned long clk_rate)  in rk3x_i2c_adapt_div()  argument
873 	struct i2c_timings *t = &i2c->t;  in rk3x_i2c_adapt_div()
880 	ret = i2c->soc_data->calc_timings(clk_rate, t, &calc);  in rk3x_i2c_adapt_div()
883 	clk_enable(i2c->pclk);  in rk3x_i2c_adapt_div()
885 	spin_lock_irqsave(&i2c->lock, flags);  in rk3x_i2c_adapt_div()
886 	val = i2c_readl(i2c, REG_CON);  in rk3x_i2c_adapt_div()
889 	i2c_writel(i2c, val, REG_CON);  in rk3x_i2c_adapt_div()
890 	i2c_writel(i2c, (calc.div_high << 16) | (calc.div_low & 0xffff),  in rk3x_i2c_adapt_div()
892 	spin_unlock_irqrestore(&i2c->lock, flags);  in rk3x_i2c_adapt_div()
894 	clk_disable(i2c->pclk);  in rk3x_i2c_adapt_div()
899 	dev_dbg(i2c->dev,  in rk3x_i2c_adapt_div()
917  * Code adapted from i2c-cadence.c.
927 	struct rk3x_i2c *i2c = container_of(nb, struct rk3x_i2c, clk_rate_nb);  in rk3x_i2c_clk_notifier_cb()  local
937 		if (i2c->soc_data->calc_timings(ndata->new_rate, &i2c->t,  in rk3x_i2c_clk_notifier_cb()
943 			rk3x_i2c_adapt_div(i2c, ndata->new_rate);  in rk3x_i2c_clk_notifier_cb()
949 			rk3x_i2c_adapt_div(i2c, ndata->new_rate);  in rk3x_i2c_clk_notifier_cb()
954 			rk3x_i2c_adapt_div(i2c, ndata->old_rate);  in rk3x_i2c_clk_notifier_cb()
962  * Setup I2C registers for an I2C operation specified by msgs, num.
964  * Must be called with i2c->lock held.
966  * @msgs: I2C msgs to process
969  * returns: Number of I2C msgs processed or negative in case of error
971 static int rk3x_i2c_setup(struct rk3x_i2c *i2c, struct i2c_msg *msgs, int num)  in rk3x_i2c_setup()  argument
977 	 * The I2C adapter can issue a small (len < 4) write packet before  in rk3x_i2c_setup()
988 		dev_dbg(i2c->dev, "Combined write/read from addr 0x%x\n",  in rk3x_i2c_setup()
998 		i2c->msg = &msgs[1];  in rk3x_i2c_setup()
1000 		i2c->mode = REG_CON_MOD_REGISTER_TX;  in rk3x_i2c_setup()
1002 		i2c_writel(i2c, addr | REG_MRXADDR_VALID(0), REG_MRXADDR);  in rk3x_i2c_setup()
1003 		i2c_writel(i2c, reg_addr, REG_MRXRADDR);  in rk3x_i2c_setup()
1019 			i2c->mode = REG_CON_MOD_REGISTER_TX;  in rk3x_i2c_setup()
1020 			i2c_writel(i2c, addr | REG_MRXADDR_VALID(0),  in rk3x_i2c_setup()
1022 			i2c_writel(i2c, 0, REG_MRXRADDR);  in rk3x_i2c_setup()
1024 			i2c->mode = REG_CON_MOD_TX;  in rk3x_i2c_setup()
1027 		i2c->msg = &msgs[0];  in rk3x_i2c_setup()
1032 	i2c->addr = msgs[0].addr;  in rk3x_i2c_setup()
1033 	i2c->busy = true;  in rk3x_i2c_setup()
1034 	i2c->state = STATE_START;  in rk3x_i2c_setup()
1035 	i2c->processed = 0;  in rk3x_i2c_setup()
1036 	i2c->error = 0;  in rk3x_i2c_setup()
1038 	rk3x_i2c_clean_ipd(i2c);  in rk3x_i2c_setup()
1046 	struct rk3x_i2c *i2c = (struct rk3x_i2c *)adap->algo_data;  in rk3x_i2c_xfer()  local
1052 	spin_lock_irqsave(&i2c->lock, flags);  in rk3x_i2c_xfer()
1054 	clk_enable(i2c->clk);  in rk3x_i2c_xfer()
1055 	clk_enable(i2c->pclk);  in rk3x_i2c_xfer()
1057 	i2c->is_last_msg = false;  in rk3x_i2c_xfer()
1064 		ret = rk3x_i2c_setup(i2c, msgs + i, num - i);  in rk3x_i2c_xfer()
1067 			dev_err(i2c->dev, "rk3x_i2c_setup() failed\n");  in rk3x_i2c_xfer()
1072 			i2c->is_last_msg = true;  in rk3x_i2c_xfer()
1074 		spin_unlock_irqrestore(&i2c->lock, flags);  in rk3x_i2c_xfer()
1076 		rk3x_i2c_start(i2c);  in rk3x_i2c_xfer()
1078 		timeout = wait_event_timeout(i2c->wait, !i2c->busy,  in rk3x_i2c_xfer()
1081 		spin_lock_irqsave(&i2c->lock, flags);  in rk3x_i2c_xfer()
1084 			dev_err(i2c->dev, "timeout, ipd: 0x%02x, state: %d\n",  in rk3x_i2c_xfer()
1085 				i2c_readl(i2c, REG_IPD), i2c->state);  in rk3x_i2c_xfer()
1088 			i2c_writel(i2c, 0, REG_IEN);  in rk3x_i2c_xfer()
1089 			val = i2c_readl(i2c, REG_CON) & REG_CON_TUNING_MASK;  in rk3x_i2c_xfer()
1091 			i2c_writel(i2c, val, REG_CON);  in rk3x_i2c_xfer()
1093 			i2c->state = STATE_IDLE;  in rk3x_i2c_xfer()
1099 		if (i2c->error) {  in rk3x_i2c_xfer()
1100 			ret = i2c->error;  in rk3x_i2c_xfer()
1105 	clk_disable(i2c->pclk);  in rk3x_i2c_xfer()
1106 	clk_disable(i2c->clk);  in rk3x_i2c_xfer()
1108 	spin_unlock_irqrestore(&i2c->lock, flags);  in rk3x_i2c_xfer()
1115 	struct rk3x_i2c *i2c = dev_get_drvdata(dev);  in rk3x_i2c_resume()  local
1117 	rk3x_i2c_adapt_div(i2c, clk_get_rate(i2c->clk));  in rk3x_i2c_resume()
1164 		.compatible = "rockchip,rv1108-i2c",
1168 		.compatible = "rockchip,rk3066-i2c",
1172 		.compatible = "rockchip,rk3188-i2c",
1176 		.compatible = "rockchip,rk3228-i2c",
1180 		.compatible = "rockchip,rk3288-i2c",
1184 		.compatible = "rockchip,rk3399-i2c",
1195 	struct rk3x_i2c *i2c;  in rk3x_i2c_probe()  local
1203 	i2c = devm_kzalloc(&pdev->dev, sizeof(struct rk3x_i2c), GFP_KERNEL);  in rk3x_i2c_probe()
1204 	if (!i2c)  in rk3x_i2c_probe()
1208 	i2c->soc_data = match->data;  in rk3x_i2c_probe()
1210 	/* use common interface to get I2C timing properties */  in rk3x_i2c_probe()
1211 	i2c_parse_fw_timings(&pdev->dev, &i2c->t, true);  in rk3x_i2c_probe()
1213 	strlcpy(i2c->adap.name, "rk3x-i2c", sizeof(i2c->adap.name));  in rk3x_i2c_probe()
1214 	i2c->adap.owner = THIS_MODULE;  in rk3x_i2c_probe()
1215 	i2c->adap.algo = &rk3x_i2c_algorithm;  in rk3x_i2c_probe()
1216 	i2c->adap.retries = 3;  in rk3x_i2c_probe()
1217 	i2c->adap.dev.of_node = np;  in rk3x_i2c_probe()
1218 	i2c->adap.algo_data = i2c;  in rk3x_i2c_probe()
1219 	i2c->adap.dev.parent = &pdev->dev;  in rk3x_i2c_probe()
1221 	i2c->dev = &pdev->dev;  in rk3x_i2c_probe()
1223 	spin_lock_init(&i2c->lock);  in rk3x_i2c_probe()
1224 	init_waitqueue_head(&i2c->wait);  in rk3x_i2c_probe()
1227 	i2c->regs = devm_ioremap_resource(&pdev->dev, mem);  in rk3x_i2c_probe()
1228 	if (IS_ERR(i2c->regs))  in rk3x_i2c_probe()
1229 		return PTR_ERR(i2c->regs);  in rk3x_i2c_probe()
1231 	/* Try to set the I2C adapter number from dt */  in rk3x_i2c_probe()
1232 	bus_nr = of_alias_get_id(np, "i2c");  in rk3x_i2c_probe()
1238 	if (i2c->soc_data->grf_offset >= 0) {  in rk3x_i2c_probe()
1244 				"rk3x-i2c needs 'rockchip,grf' property\n");  in rk3x_i2c_probe()
1249 			dev_err(&pdev->dev, "rk3x-i2c needs i2cX alias");  in rk3x_i2c_probe()
1256 		ret = regmap_write(grf, i2c->soc_data->grf_offset, value);  in rk3x_i2c_probe()
1258 			dev_err(i2c->dev, "Could not write to GRF: %d\n", ret);  in rk3x_i2c_probe()
1271 			       0, dev_name(&pdev->dev), i2c);  in rk3x_i2c_probe()
1277 	platform_set_drvdata(pdev, i2c);  in rk3x_i2c_probe()
1279 	if (i2c->soc_data->calc_timings == rk3x_i2c_v0_calc_timings) {  in rk3x_i2c_probe()
1281 		i2c->clk = devm_clk_get(&pdev->dev, NULL);  in rk3x_i2c_probe()
1282 		i2c->pclk = i2c->clk;  in rk3x_i2c_probe()
1284 		i2c->clk = devm_clk_get(&pdev->dev, "i2c");  in rk3x_i2c_probe()
1285 		i2c->pclk = devm_clk_get(&pdev->dev, "pclk");  in rk3x_i2c_probe()
1288 	if (IS_ERR(i2c->clk)) {  in rk3x_i2c_probe()
1289 		ret = PTR_ERR(i2c->clk);  in rk3x_i2c_probe()
1294 	if (IS_ERR(i2c->pclk)) {  in rk3x_i2c_probe()
1295 		ret = PTR_ERR(i2c->pclk);  in rk3x_i2c_probe()
1301 	ret = clk_prepare(i2c->clk);  in rk3x_i2c_probe()
1306 	ret = clk_prepare(i2c->pclk);  in rk3x_i2c_probe()
1312 	i2c->clk_rate_nb.notifier_call = rk3x_i2c_clk_notifier_cb;  in rk3x_i2c_probe()
1313 	ret = clk_notifier_register(i2c->clk, &i2c->clk_rate_nb);  in rk3x_i2c_probe()
1319 	clk_rate = clk_get_rate(i2c->clk);  in rk3x_i2c_probe()
1320 	rk3x_i2c_adapt_div(i2c, clk_rate);  in rk3x_i2c_probe()
1322 	ret = i2c_add_adapter(&i2c->adap);  in rk3x_i2c_probe()
1329 	clk_notifier_unregister(i2c->clk, &i2c->clk_rate_nb);  in rk3x_i2c_probe()
1331 	clk_unprepare(i2c->pclk);  in rk3x_i2c_probe()
1333 	clk_unprepare(i2c->clk);  in rk3x_i2c_probe()
1339 	struct rk3x_i2c *i2c = platform_get_drvdata(pdev);  in rk3x_i2c_remove()  local
1341 	i2c_del_adapter(&i2c->adap);  in rk3x_i2c_remove()
1343 	clk_notifier_unregister(i2c->clk, &i2c->clk_rate_nb);  in rk3x_i2c_remove()
1344 	clk_unprepare(i2c->pclk);  in rk3x_i2c_remove()
1345 	clk_unprepare(i2c->clk);  in rk3x_i2c_remove()
1356 		.name  = "rk3x-i2c",
1364 MODULE_DESCRIPTION("Rockchip RK3xxx I2C Bus driver");