1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
5 #include <linux/dma-mapping.h>
8 #include <linux/interrupt.h>
10 #include <linux/module.h>
12 #include <linux/of_platform.h>
13 #include <linux/platform_device.h>
14 #include <linux/pm_runtime.h>
15 #include <linux/qcom-geni-se.h>
16 #include <linux/spinlock.h>
18 #define SE_I2C_TX_TRANS_LEN 0x26c
19 #define SE_I2C_RX_TRANS_LEN 0x270
20 #define SE_I2C_SCL_COUNTERS 0x278
22 #define SE_I2C_ERR (M_CMD_OVERRUN_EN | M_ILLEGAL_CMD_EN | M_CMD_FAILURE_EN |\
23 M_GP_IRQ_1_EN | M_GP_IRQ_3_EN | M_GP_IRQ_4_EN)
24 #define SE_I2C_ABORT BIT(1)
26 /* M_CMD OP codes for I2C */
29 #define I2C_WRITE_READ 0x3
30 #define I2C_ADDR_ONLY 0x4
31 #define I2C_BUS_CLEAR 0x6
32 #define I2C_STOP_ON_BUS 0x7
33 /* M_CMD params for I2C */
34 #define PRE_CMD_DELAY BIT(0)
35 #define TIMESTAMP_BEFORE BIT(1)
36 #define STOP_STRETCH BIT(2)
37 #define TIMESTAMP_AFTER BIT(3)
38 #define POST_COMMAND_DELAY BIT(4)
39 #define IGNORE_ADD_NACK BIT(6)
40 #define READ_FINISHED_WITH_ACK BIT(7)
41 #define BYPASS_ADDR_PHASE BIT(8)
42 #define SLV_ADDR_MSK GENMASK(15, 9)
43 #define SLV_ADDR_SHFT 9
44 /* I2C SCL COUNTER fields */
45 #define HIGH_COUNTER_MSK GENMASK(29, 20)
46 #define HIGH_COUNTER_SHFT 20
47 #define LOW_COUNTER_MSK GENMASK(19, 10)
48 #define LOW_COUNTER_SHFT 10
49 #define CYCLE_COUNTER_MSK GENMASK(9, 0)
51 enum geni_i2c_err_code {
64 #define DM_I2C_CB_ERR ((BIT(NACK) | BIT(BUS_PROTO) | BIT(ARB_LOST)) \
67 #define I2C_AUTO_SUSPEND_DELAY 250
68 #define KHZ(freq) (1000 * freq)
69 #define PACKING_BYTES_PW 4
71 #define ABORT_TIMEOUT HZ
72 #define XFER_TIMEOUT HZ
73 #define RST_TIMEOUT HZ
80 struct i2c_adapter adap;
81 struct completion done;
87 const struct geni_i2c_clk_fld *clk_fld;
91 struct geni_i2c_err_log {
96 static const struct geni_i2c_err_log gi2c_log[] = {
97 [GP_IRQ0] = {-EIO, "Unknown I2C err GP_IRQ0"},
98 [NACK] = {-ENXIO, "NACK: slv unresponsive, check its power/reset-ln"},
99 [GP_IRQ2] = {-EIO, "Unknown I2C err GP IRQ2"},
100 [BUS_PROTO] = {-EPROTO, "Bus proto err, noisy/unepxected start/stop"},
101 [ARB_LOST] = {-EAGAIN, "Bus arbitration lost, clock line undriveable"},
102 [GP_IRQ5] = {-EIO, "Unknown I2C err GP IRQ5"},
103 [GENI_OVERRUN] = {-EIO, "Cmd overrun, check GENI cmd-state machine"},
104 [GENI_ILLEGAL_CMD] = {-EIO, "Illegal cmd, check GENI cmd-state machine"},
105 [GENI_ABORT_DONE] = {-ETIMEDOUT, "Abort after timeout successful"},
106 [GENI_TIMEOUT] = {-ETIMEDOUT, "I2C TXN timed out"},
109 struct geni_i2c_clk_fld {
118 * Hardware uses the underlying formula to calculate time periods of
119 * SCL clock cycle. Firmware uses some additional cycles excluded from the
120 * below formula and it is confirmed that the time periods are within
121 * specification limits.
123 * time of high period of SCL: t_high = (t_high_cnt * clk_div) / source_clock
124 * time of low period of SCL: t_low = (t_low_cnt * clk_div) / source_clock
125 * time of full period of SCL: t_cycle = (t_cycle_cnt * clk_div) / source_clock
126 * clk_freq_out = t / t_cycle
127 * source_clock = 19.2 MHz
129 static const struct geni_i2c_clk_fld geni_i2c_clk_map[] = {
130 {KHZ(100), 7, 10, 11, 26},
131 {KHZ(400), 2, 5, 12, 24},
132 {KHZ(1000), 1, 3, 9, 18},
135 static int geni_i2c_clk_map_idx(struct geni_i2c_dev *gi2c)
138 const struct geni_i2c_clk_fld *itr = geni_i2c_clk_map;
140 for (i = 0; i < ARRAY_SIZE(geni_i2c_clk_map); i++, itr++) {
141 if (itr->clk_freq_out == gi2c->clk_freq_out) {
149 static void qcom_geni_i2c_conf(struct geni_i2c_dev *gi2c)
151 const struct geni_i2c_clk_fld *itr = gi2c->clk_fld;
154 writel_relaxed(0, gi2c->se.base + SE_GENI_CLK_SEL);
156 val = (itr->clk_div << CLK_DIV_SHFT) | SER_CLK_EN;
157 writel_relaxed(val, gi2c->se.base + GENI_SER_M_CLK_CFG);
159 val = itr->t_high_cnt << HIGH_COUNTER_SHFT;
160 val |= itr->t_low_cnt << LOW_COUNTER_SHFT;
161 val |= itr->t_cycle_cnt;
162 writel_relaxed(val, gi2c->se.base + SE_I2C_SCL_COUNTERS);
165 static void geni_i2c_err_misc(struct geni_i2c_dev *gi2c)
167 u32 m_cmd = readl_relaxed(gi2c->se.base + SE_GENI_M_CMD0);
168 u32 m_stat = readl_relaxed(gi2c->se.base + SE_GENI_M_IRQ_STATUS);
169 u32 geni_s = readl_relaxed(gi2c->se.base + SE_GENI_STATUS);
170 u32 geni_ios = readl_relaxed(gi2c->se.base + SE_GENI_IOS);
171 u32 dma = readl_relaxed(gi2c->se.base + SE_GENI_DMA_MODE_EN);
175 rx_st = readl_relaxed(gi2c->se.base + SE_DMA_RX_IRQ_STAT);
176 tx_st = readl_relaxed(gi2c->se.base + SE_DMA_TX_IRQ_STAT);
178 rx_st = readl_relaxed(gi2c->se.base + SE_GENI_RX_FIFO_STATUS);
179 tx_st = readl_relaxed(gi2c->se.base + SE_GENI_TX_FIFO_STATUS);
181 dev_dbg(gi2c->se.dev, "DMA:%d tx_stat:0x%x, rx_stat:0x%x, irq-stat:0x%x\n",
182 dma, tx_st, rx_st, m_stat);
183 dev_dbg(gi2c->se.dev, "m_cmd:0x%x, geni_status:0x%x, geni_ios:0x%x\n",
184 m_cmd, geni_s, geni_ios);
187 static void geni_i2c_err(struct geni_i2c_dev *gi2c, int err)
190 gi2c->err = gi2c_log[err].err;
192 dev_dbg(gi2c->se.dev, "len:%d, slv-addr:0x%x, RD/WR:%d\n",
193 gi2c->cur->len, gi2c->cur->addr, gi2c->cur->flags);
195 if (err != NACK && err != GENI_ABORT_DONE) {
196 dev_err(gi2c->se.dev, "%s\n", gi2c_log[err].msg);
197 geni_i2c_err_misc(gi2c);
201 static irqreturn_t geni_i2c_irq(int irq, void *dev)
203 struct geni_i2c_dev *gi2c = dev;
204 void __iomem *base = gi2c->se.base;
215 spin_lock_irqsave(&gi2c->lock, flags);
216 m_stat = readl_relaxed(base + SE_GENI_M_IRQ_STATUS);
217 rx_st = readl_relaxed(base + SE_GENI_RX_FIFO_STATUS);
218 dm_tx_st = readl_relaxed(base + SE_DMA_TX_IRQ_STAT);
219 dm_rx_st = readl_relaxed(base + SE_DMA_RX_IRQ_STAT);
220 dma = readl_relaxed(base + SE_GENI_DMA_MODE_EN);
224 m_stat & (M_CMD_FAILURE_EN | M_CMD_ABORT_EN) ||
225 dm_rx_st & (DM_I2C_CB_ERR)) {
226 if (m_stat & M_GP_IRQ_1_EN)
227 geni_i2c_err(gi2c, NACK);
228 if (m_stat & M_GP_IRQ_3_EN)
229 geni_i2c_err(gi2c, BUS_PROTO);
230 if (m_stat & M_GP_IRQ_4_EN)
231 geni_i2c_err(gi2c, ARB_LOST);
232 if (m_stat & M_CMD_OVERRUN_EN)
233 geni_i2c_err(gi2c, GENI_OVERRUN);
234 if (m_stat & M_ILLEGAL_CMD_EN)
235 geni_i2c_err(gi2c, GENI_ILLEGAL_CMD);
236 if (m_stat & M_CMD_ABORT_EN)
237 geni_i2c_err(gi2c, GENI_ABORT_DONE);
238 if (m_stat & M_GP_IRQ_0_EN)
239 geni_i2c_err(gi2c, GP_IRQ0);
241 /* Disable the TX Watermark interrupt to stop TX */
243 writel_relaxed(0, base + SE_GENI_TX_WATERMARK_REG);
245 dev_dbg(gi2c->se.dev, "i2c dma tx:0x%x, dma rx:0x%x\n",
247 } else if (cur->flags & I2C_M_RD &&
248 m_stat & (M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN)) {
249 u32 rxcnt = rx_st & RX_FIFO_WC_MSK;
251 for (j = 0; j < rxcnt; j++) {
253 val = readl_relaxed(base + SE_GENI_RX_FIFOn);
254 while (gi2c->cur_rd < cur->len && p < sizeof(val)) {
255 cur->buf[gi2c->cur_rd++] = val & 0xff;
259 if (gi2c->cur_rd == cur->len)
262 } else if (!(cur->flags & I2C_M_RD) &&
263 m_stat & M_TX_FIFO_WATERMARK_EN) {
264 for (j = 0; j < gi2c->tx_wm; j++) {
269 while (gi2c->cur_wr < cur->len && p < sizeof(val)) {
270 temp = cur->buf[gi2c->cur_wr++];
271 val |= temp << (p * 8);
274 writel_relaxed(val, base + SE_GENI_TX_FIFOn);
275 /* TX Complete, Disable the TX Watermark interrupt */
276 if (gi2c->cur_wr == cur->len) {
277 writel_relaxed(0, base + SE_GENI_TX_WATERMARK_REG);
284 writel_relaxed(m_stat, base + SE_GENI_M_IRQ_CLEAR);
287 writel_relaxed(dm_tx_st, base + SE_DMA_TX_IRQ_CLR);
289 writel_relaxed(dm_rx_st, base + SE_DMA_RX_IRQ_CLR);
291 /* if this is err with done-bit not set, handle that through timeout. */
292 if (m_stat & M_CMD_DONE_EN || m_stat & M_CMD_ABORT_EN ||
293 dm_tx_st & TX_DMA_DONE || dm_tx_st & TX_RESET_DONE ||
294 dm_rx_st & RX_DMA_DONE || dm_rx_st & RX_RESET_DONE)
295 complete(&gi2c->done);
297 spin_unlock_irqrestore(&gi2c->lock, flags);
302 static void geni_i2c_abort_xfer(struct geni_i2c_dev *gi2c)
305 unsigned long time_left = ABORT_TIMEOUT;
308 spin_lock_irqsave(&gi2c->lock, flags);
309 geni_i2c_err(gi2c, GENI_TIMEOUT);
311 geni_se_abort_m_cmd(&gi2c->se);
312 spin_unlock_irqrestore(&gi2c->lock, flags);
314 time_left = wait_for_completion_timeout(&gi2c->done, time_left);
315 val = readl_relaxed(gi2c->se.base + SE_GENI_M_IRQ_STATUS);
316 } while (!(val & M_CMD_ABORT_EN) && time_left);
318 if (!(val & M_CMD_ABORT_EN))
319 dev_err(gi2c->se.dev, "Timeout abort_m_cmd\n");
322 static void geni_i2c_rx_fsm_rst(struct geni_i2c_dev *gi2c)
325 unsigned long time_left = RST_TIMEOUT;
327 writel_relaxed(1, gi2c->se.base + SE_DMA_RX_FSM_RST);
329 time_left = wait_for_completion_timeout(&gi2c->done, time_left);
330 val = readl_relaxed(gi2c->se.base + SE_DMA_RX_IRQ_STAT);
331 } while (!(val & RX_RESET_DONE) && time_left);
333 if (!(val & RX_RESET_DONE))
334 dev_err(gi2c->se.dev, "Timeout resetting RX_FSM\n");
337 static void geni_i2c_tx_fsm_rst(struct geni_i2c_dev *gi2c)
340 unsigned long time_left = RST_TIMEOUT;
342 writel_relaxed(1, gi2c->se.base + SE_DMA_TX_FSM_RST);
344 time_left = wait_for_completion_timeout(&gi2c->done, time_left);
345 val = readl_relaxed(gi2c->se.base + SE_DMA_TX_IRQ_STAT);
346 } while (!(val & TX_RESET_DONE) && time_left);
348 if (!(val & TX_RESET_DONE))
349 dev_err(gi2c->se.dev, "Timeout resetting TX_FSM\n");
352 static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
356 unsigned long time_left;
358 struct geni_se *se = &gi2c->se;
359 size_t len = msg->len;
361 dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
363 geni_se_select_mode(se, GENI_SE_DMA);
365 geni_se_select_mode(se, GENI_SE_FIFO);
367 writel_relaxed(len, se->base + SE_I2C_RX_TRANS_LEN);
368 geni_se_setup_m_cmd(se, I2C_READ, m_param);
370 if (dma_buf && geni_se_rx_dma_prep(se, dma_buf, len, &rx_dma)) {
371 geni_se_select_mode(se, GENI_SE_FIFO);
372 i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
376 time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
378 geni_i2c_abort_xfer(gi2c);
383 geni_i2c_rx_fsm_rst(gi2c);
384 geni_se_rx_dma_unprep(se, rx_dma, len);
385 i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err);
391 static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
395 unsigned long time_left;
397 struct geni_se *se = &gi2c->se;
398 size_t len = msg->len;
400 dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
402 geni_se_select_mode(se, GENI_SE_DMA);
404 geni_se_select_mode(se, GENI_SE_FIFO);
406 writel_relaxed(len, se->base + SE_I2C_TX_TRANS_LEN);
407 geni_se_setup_m_cmd(se, I2C_WRITE, m_param);
409 if (dma_buf && geni_se_tx_dma_prep(se, dma_buf, len, &tx_dma)) {
410 geni_se_select_mode(se, GENI_SE_FIFO);
411 i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
415 if (!dma_buf) /* Get FIFO IRQ */
416 writel_relaxed(1, se->base + SE_GENI_TX_WATERMARK_REG);
418 time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
420 geni_i2c_abort_xfer(gi2c);
425 geni_i2c_tx_fsm_rst(gi2c);
426 geni_se_tx_dma_unprep(se, tx_dma, len);
427 i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err);
433 static int geni_i2c_xfer(struct i2c_adapter *adap,
434 struct i2c_msg msgs[],
437 struct geni_i2c_dev *gi2c = i2c_get_adapdata(adap);
441 reinit_completion(&gi2c->done);
442 ret = pm_runtime_get_sync(gi2c->se.dev);
444 dev_err(gi2c->se.dev, "error turning SE resources:%d\n", ret);
445 pm_runtime_put_noidle(gi2c->se.dev);
446 /* Set device in suspended since resume failed */
447 pm_runtime_set_suspended(gi2c->se.dev);
451 qcom_geni_i2c_conf(gi2c);
452 for (i = 0; i < num; i++) {
453 u32 m_param = i < (num - 1) ? STOP_STRETCH : 0;
455 m_param |= ((msgs[i].addr << SLV_ADDR_SHFT) & SLV_ADDR_MSK);
457 gi2c->cur = &msgs[i];
458 if (msgs[i].flags & I2C_M_RD)
459 ret = geni_i2c_rx_one_msg(gi2c, &msgs[i], m_param);
461 ret = geni_i2c_tx_one_msg(gi2c, &msgs[i], m_param);
469 pm_runtime_mark_last_busy(gi2c->se.dev);
470 pm_runtime_put_autosuspend(gi2c->se.dev);
476 static u32 geni_i2c_func(struct i2c_adapter *adap)
478 return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
481 static const struct i2c_algorithm geni_i2c_algo = {
482 .master_xfer = geni_i2c_xfer,
483 .functionality = geni_i2c_func,
486 static int geni_i2c_probe(struct platform_device *pdev)
488 struct geni_i2c_dev *gi2c;
489 struct resource *res;
493 gi2c = devm_kzalloc(&pdev->dev, sizeof(*gi2c), GFP_KERNEL);
497 gi2c->se.dev = &pdev->dev;
498 gi2c->se.wrapper = dev_get_drvdata(pdev->dev.parent);
499 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
500 gi2c->se.base = devm_ioremap_resource(&pdev->dev, res);
501 if (IS_ERR(gi2c->se.base))
502 return PTR_ERR(gi2c->se.base);
504 gi2c->se.clk = devm_clk_get(&pdev->dev, "se");
505 if (IS_ERR(gi2c->se.clk)) {
506 ret = PTR_ERR(gi2c->se.clk);
507 dev_err(&pdev->dev, "Err getting SE Core clk %d\n", ret);
511 ret = device_property_read_u32(&pdev->dev, "clock-frequency",
512 &gi2c->clk_freq_out);
515 "Bus frequency not specified, default to 100kHz.\n");
516 gi2c->clk_freq_out = KHZ(100);
519 gi2c->irq = platform_get_irq(pdev, 0);
521 dev_err(&pdev->dev, "IRQ error for i2c-geni\n");
525 ret = geni_i2c_clk_map_idx(gi2c);
527 dev_err(&pdev->dev, "Invalid clk frequency %d Hz: %d\n",
528 gi2c->clk_freq_out, ret);
532 gi2c->adap.algo = &geni_i2c_algo;
533 init_completion(&gi2c->done);
534 spin_lock_init(&gi2c->lock);
535 platform_set_drvdata(pdev, gi2c);
536 ret = devm_request_irq(&pdev->dev, gi2c->irq, geni_i2c_irq,
537 IRQF_TRIGGER_HIGH, "i2c_geni", gi2c);
539 dev_err(&pdev->dev, "Request_irq failed:%d: err:%d\n",
543 /* Disable the interrupt so that the system can enter low-power mode */
544 disable_irq(gi2c->irq);
545 i2c_set_adapdata(&gi2c->adap, gi2c);
546 gi2c->adap.dev.parent = &pdev->dev;
547 gi2c->adap.dev.of_node = pdev->dev.of_node;
548 strlcpy(gi2c->adap.name, "Geni-I2C", sizeof(gi2c->adap.name));
550 ret = geni_se_resources_on(&gi2c->se);
552 dev_err(&pdev->dev, "Error turning on resources %d\n", ret);
555 proto = geni_se_read_proto(&gi2c->se);
556 tx_depth = geni_se_get_tx_fifo_depth(&gi2c->se);
557 if (proto != GENI_SE_I2C) {
558 dev_err(&pdev->dev, "Invalid proto %d\n", proto);
559 geni_se_resources_off(&gi2c->se);
562 gi2c->tx_wm = tx_depth - 1;
563 geni_se_init(&gi2c->se, gi2c->tx_wm, tx_depth);
564 geni_se_config_packing(&gi2c->se, BITS_PER_BYTE, PACKING_BYTES_PW,
566 ret = geni_se_resources_off(&gi2c->se);
568 dev_err(&pdev->dev, "Error turning off resources %d\n", ret);
572 dev_dbg(&pdev->dev, "i2c fifo/se-dma mode. fifo depth:%d\n", tx_depth);
574 ret = i2c_add_adapter(&gi2c->adap);
576 dev_err(&pdev->dev, "Error adding i2c adapter %d\n", ret);
581 pm_runtime_set_suspended(gi2c->se.dev);
582 pm_runtime_set_autosuspend_delay(gi2c->se.dev, I2C_AUTO_SUSPEND_DELAY);
583 pm_runtime_use_autosuspend(gi2c->se.dev);
584 pm_runtime_enable(gi2c->se.dev);
589 static int geni_i2c_remove(struct platform_device *pdev)
591 struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);
593 pm_runtime_disable(gi2c->se.dev);
594 i2c_del_adapter(&gi2c->adap);
598 static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev)
601 struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
603 disable_irq(gi2c->irq);
604 ret = geni_se_resources_off(&gi2c->se);
606 enable_irq(gi2c->irq);
616 static int __maybe_unused geni_i2c_runtime_resume(struct device *dev)
619 struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
621 ret = geni_se_resources_on(&gi2c->se);
625 enable_irq(gi2c->irq);
630 static int __maybe_unused geni_i2c_suspend_noirq(struct device *dev)
632 struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
634 if (!gi2c->suspended) {
635 geni_i2c_runtime_suspend(dev);
636 pm_runtime_disable(dev);
637 pm_runtime_set_suspended(dev);
638 pm_runtime_enable(dev);
643 static const struct dev_pm_ops geni_i2c_pm_ops = {
644 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(geni_i2c_suspend_noirq, NULL)
645 SET_RUNTIME_PM_OPS(geni_i2c_runtime_suspend, geni_i2c_runtime_resume,
649 static const struct of_device_id geni_i2c_dt_match[] = {
650 { .compatible = "qcom,geni-i2c" },
653 MODULE_DEVICE_TABLE(of, geni_i2c_dt_match);
655 static struct platform_driver geni_i2c_driver = {
656 .probe = geni_i2c_probe,
657 .remove = geni_i2c_remove,
660 .pm = &geni_i2c_pm_ops,
661 .of_match_table = geni_i2c_dt_match,
665 module_platform_driver(geni_i2c_driver);
667 MODULE_DESCRIPTION("I2C Controller Driver for GENI based QUP cores");
668 MODULE_LICENSE("GPL v2");