1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Synopsys DesignWare I2C adapter driver.
5 * Based on the TI DAVINCI I2C adapter driver.
7 * Copyright (C) 2006 Texas Instruments.
8 * Copyright (C) 2007 MontaVista Software Inc.
9 * Copyright (C) 2009 Provigent Ltd.
11 #include <linux/acpi.h>
12 #include <linux/clk-provider.h>
13 #include <linux/clk.h>
14 #include <linux/delay.h>
15 #include <linux/dmi.h>
16 #include <linux/err.h>
17 #include <linux/errno.h>
18 #include <linux/i2c.h>
19 #include <linux/interrupt.h>
21 #include <linux/kernel.h>
22 #include <linux/module.h>
24 #include <linux/platform_data/i2c-designware.h>
25 #include <linux/platform_device.h>
27 #include <linux/pm_runtime.h>
28 #include <linux/property.h>
29 #include <linux/reset.h>
30 #include <linux/sched.h>
31 #include <linux/slab.h>
32 #include <linux/suspend.h>
34 #include "i2c-designware-core.h"
36 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
38 return clk_get_rate(dev->clk)/1000;
43 * The HCNT/LCNT information coming from ACPI should be the most accurate
44 * for given platform. However, some systems get it wrong. On such systems
45 * we get better results by calculating those based on the input clock.
47 static const struct dmi_system_id dw_i2c_no_acpi_params[] = {
49 .ident = "Dell Inspiron 7348",
51 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
52 DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7348"),
58 static void dw_i2c_acpi_params(struct platform_device *pdev, char method[],
59 u16 *hcnt, u16 *lcnt, u32 *sda_hold)
61 struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
62 acpi_handle handle = ACPI_HANDLE(&pdev->dev);
63 union acpi_object *obj;
65 if (dmi_check_system(dw_i2c_no_acpi_params))
68 if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf)))
71 obj = (union acpi_object *)buf.pointer;
72 if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) {
73 const union acpi_object *objs = obj->package.elements;
75 *hcnt = (u16)objs[0].integer.value;
76 *lcnt = (u16)objs[1].integer.value;
77 *sda_hold = (u32)objs[2].integer.value;
83 static int dw_i2c_acpi_configure(struct platform_device *pdev)
85 struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
86 struct i2c_timings *t = &dev->timings;
87 u32 ss_ht = 0, fp_ht = 0, hs_ht = 0, fs_ht = 0;
90 dev->tx_fifo_depth = 32;
91 dev->rx_fifo_depth = 32;
94 * Try to get SDA hold time and *CNT values from an ACPI method for
95 * selected speed modes.
97 dw_i2c_acpi_params(pdev, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, &ss_ht);
98 dw_i2c_acpi_params(pdev, "FPCN", &dev->fp_hcnt, &dev->fp_lcnt, &fp_ht);
99 dw_i2c_acpi_params(pdev, "HSCN", &dev->hs_hcnt, &dev->hs_lcnt, &hs_ht);
100 dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, &fs_ht);
102 switch (t->bus_freq_hz) {
104 dev->sda_hold_time = ss_ht;
107 dev->sda_hold_time = fp_ht;
110 dev->sda_hold_time = hs_ht;
114 dev->sda_hold_time = fs_ht;
121 static const struct acpi_device_id dw_i2c_acpi_match[] = {
126 { "80860F41", ACCESS_NO_IRQ_SUSPEND },
127 { "808622C1", ACCESS_NO_IRQ_SUSPEND | MODEL_CHERRYTRAIL },
128 { "AMD0010", ACCESS_INTR_MASK },
129 { "AMDI0010", ACCESS_INTR_MASK },
136 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
138 static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
145 #define MSCC_ICPU_CFG_TWI_DELAY 0x0
146 #define MSCC_ICPU_CFG_TWI_DELAY_ENABLE BIT(0)
147 #define MSCC_ICPU_CFG_TWI_SPIKE_FILTER 0x4
149 static int mscc_twi_set_sda_hold_time(struct dw_i2c_dev *dev)
151 writel((dev->sda_hold_time << 1) | MSCC_ICPU_CFG_TWI_DELAY_ENABLE,
152 dev->ext + MSCC_ICPU_CFG_TWI_DELAY);
157 static int dw_i2c_of_configure(struct platform_device *pdev)
159 struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
160 struct resource *mem;
162 switch (dev->flags & MODEL_MASK) {
163 case MODEL_MSCC_OCELOT:
164 mem = platform_get_resource(pdev, IORESOURCE_MEM, 1);
165 dev->ext = devm_ioremap_resource(&pdev->dev, mem);
166 if (!IS_ERR(dev->ext))
167 dev->set_sda_hold_time = mscc_twi_set_sda_hold_time;
176 static const struct of_device_id dw_i2c_of_match[] = {
177 { .compatible = "snps,designware-i2c", },
178 { .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT },
181 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
183 static inline int dw_i2c_of_configure(struct platform_device *pdev)
189 static void i2c_dw_configure_master(struct dw_i2c_dev *dev)
191 struct i2c_timings *t = &dev->timings;
193 dev->functionality = I2C_FUNC_10BIT_ADDR | DW_IC_DEFAULT_FUNCTIONALITY;
195 dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
196 DW_IC_CON_RESTART_EN;
198 dev->mode = DW_IC_MASTER;
200 switch (t->bus_freq_hz) {
202 dev->master_cfg |= DW_IC_CON_SPEED_STD;
205 dev->master_cfg |= DW_IC_CON_SPEED_HIGH;
208 dev->master_cfg |= DW_IC_CON_SPEED_FAST;
212 static void i2c_dw_configure_slave(struct dw_i2c_dev *dev)
214 dev->functionality = I2C_FUNC_SLAVE | DW_IC_DEFAULT_FUNCTIONALITY;
216 dev->slave_cfg = DW_IC_CON_RX_FIFO_FULL_HLD_CTRL |
217 DW_IC_CON_RESTART_EN | DW_IC_CON_STOP_DET_IFADDRESSED;
219 dev->mode = DW_IC_SLAVE;
222 static void dw_i2c_set_fifo_size(struct dw_i2c_dev *dev, int id)
224 u32 param, tx_fifo_depth, rx_fifo_depth;
227 * Try to detect the FIFO depth if not set by interface driver,
228 * the depth could be from 2 to 256 from HW spec.
230 param = i2c_dw_read_comp_param(dev);
231 tx_fifo_depth = ((param >> 16) & 0xff) + 1;
232 rx_fifo_depth = ((param >> 8) & 0xff) + 1;
233 if (!dev->tx_fifo_depth) {
234 dev->tx_fifo_depth = tx_fifo_depth;
235 dev->rx_fifo_depth = rx_fifo_depth;
236 dev->adapter.nr = id;
237 } else if (tx_fifo_depth >= 2) {
238 dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth,
240 dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth,
245 static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev)
247 pm_runtime_disable(dev->dev);
249 if (dev->shared_with_punit)
250 pm_runtime_put_noidle(dev->dev);
253 static int dw_i2c_plat_probe(struct platform_device *pdev)
255 struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
256 struct i2c_adapter *adap;
257 struct dw_i2c_dev *dev;
258 struct i2c_timings *t;
260 struct resource *mem;
262 static const int supported_speeds[] = {
263 0, 100000, 400000, 1000000, 3400000
266 irq = platform_get_irq(pdev, 0);
270 dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
274 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
275 dev->base = devm_ioremap_resource(&pdev->dev, mem);
276 if (IS_ERR(dev->base))
277 return PTR_ERR(dev->base);
279 dev->dev = &pdev->dev;
281 platform_set_drvdata(pdev, dev);
283 dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
284 if (IS_ERR(dev->rst)) {
285 if (PTR_ERR(dev->rst) == -EPROBE_DEFER)
286 return -EPROBE_DEFER;
288 reset_control_deassert(dev->rst);
293 t->bus_freq_hz = pdata->i2c_scl_freq;
295 i2c_parse_fw_timings(&pdev->dev, t, false);
297 acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev);
299 * Some DSTDs use a non standard speed, round down to the lowest
302 for (i = 1; i < ARRAY_SIZE(supported_speeds); i++) {
303 if (acpi_speed < supported_speeds[i])
306 acpi_speed = supported_speeds[i - 1];
309 * Find bus speed from the "clock-frequency" device property, ACPI
310 * or by using fast mode if neither is set.
312 if (acpi_speed && t->bus_freq_hz)
313 t->bus_freq_hz = min(t->bus_freq_hz, acpi_speed);
314 else if (acpi_speed || t->bus_freq_hz)
315 t->bus_freq_hz = max(t->bus_freq_hz, acpi_speed);
317 t->bus_freq_hz = 400000;
319 dev->flags |= (uintptr_t)device_get_match_data(&pdev->dev);
321 if (pdev->dev.of_node)
322 dw_i2c_of_configure(pdev);
324 if (has_acpi_companion(&pdev->dev))
325 dw_i2c_acpi_configure(pdev);
328 * Only standard mode at 100kHz, fast mode at 400kHz,
329 * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported.
331 if (t->bus_freq_hz != 100000 && t->bus_freq_hz != 400000 &&
332 t->bus_freq_hz != 1000000 && t->bus_freq_hz != 3400000) {
334 "%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n",
340 ret = i2c_dw_probe_lock_support(dev);
344 if (i2c_detect_slave_mode(&pdev->dev))
345 i2c_dw_configure_slave(dev);
347 i2c_dw_configure_master(dev);
349 dev->clk = devm_clk_get(&pdev->dev, NULL);
350 if (!i2c_dw_prepare_clk(dev, true)) {
353 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
354 clk_khz = dev->get_clk_rate_khz(dev);
356 if (!dev->sda_hold_time && t->sda_hold_ns)
358 div_u64(clk_khz * t->sda_hold_ns + 500000, 1000000);
361 dw_i2c_set_fifo_size(dev, pdev->id);
363 adap = &dev->adapter;
364 adap->owner = THIS_MODULE;
365 adap->class = I2C_CLASS_DEPRECATED;
366 ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
367 adap->dev.of_node = pdev->dev.of_node;
369 dev_pm_set_driver_flags(&pdev->dev,
370 DPM_FLAG_SMART_PREPARE |
371 DPM_FLAG_SMART_SUSPEND |
372 DPM_FLAG_LEAVE_SUSPENDED);
374 /* The code below assumes runtime PM to be disabled. */
375 WARN_ON(pm_runtime_enabled(&pdev->dev));
377 pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
378 pm_runtime_use_autosuspend(&pdev->dev);
379 pm_runtime_set_active(&pdev->dev);
381 if (dev->shared_with_punit)
382 pm_runtime_get_noresume(&pdev->dev);
384 pm_runtime_enable(&pdev->dev);
386 if (dev->mode == DW_IC_SLAVE)
387 ret = i2c_dw_probe_slave(dev);
389 ret = i2c_dw_probe(dev);
397 dw_i2c_plat_pm_cleanup(dev);
399 if (!IS_ERR_OR_NULL(dev->rst))
400 reset_control_assert(dev->rst);
404 static int dw_i2c_plat_remove(struct platform_device *pdev)
406 struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
408 pm_runtime_get_sync(&pdev->dev);
410 i2c_del_adapter(&dev->adapter);
414 pm_runtime_dont_use_autosuspend(&pdev->dev);
415 pm_runtime_put_sync(&pdev->dev);
416 dw_i2c_plat_pm_cleanup(dev);
418 if (!IS_ERR_OR_NULL(dev->rst))
419 reset_control_assert(dev->rst);
424 #ifdef CONFIG_PM_SLEEP
425 static int dw_i2c_plat_prepare(struct device *dev)
428 * If the ACPI companion device object is present for this device, it
429 * may be accessed during suspend and resume of other devices via I2C
430 * operation regions, so tell the PM core and middle layers to avoid
431 * skipping system suspend/resume callbacks for it in that case.
433 return !has_acpi_companion(dev);
436 static void dw_i2c_plat_complete(struct device *dev)
439 * The device can only be in runtime suspend at this point if it has not
440 * been resumed throughout the ending system suspend/resume cycle, so if
441 * the platform firmware might mess up with it, request the runtime PM
442 * framework to resume it.
444 if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
445 pm_request_resume(dev);
448 #define dw_i2c_plat_prepare NULL
449 #define dw_i2c_plat_complete NULL
453 static int dw_i2c_plat_suspend(struct device *dev)
455 struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
457 if (i_dev->shared_with_punit)
460 i_dev->disable(i_dev);
461 i2c_dw_prepare_clk(i_dev, false);
466 static int dw_i2c_plat_resume(struct device *dev)
468 struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
470 if (!i_dev->shared_with_punit)
471 i2c_dw_prepare_clk(i_dev, true);
478 static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
479 .prepare = dw_i2c_plat_prepare,
480 .complete = dw_i2c_plat_complete,
481 SET_LATE_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
482 SET_RUNTIME_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume, NULL)
485 #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops)
487 #define DW_I2C_DEV_PMOPS NULL
490 /* Work with hotplug and coldplug */
491 MODULE_ALIAS("platform:i2c_designware");
493 static struct platform_driver dw_i2c_driver = {
494 .probe = dw_i2c_plat_probe,
495 .remove = dw_i2c_plat_remove,
497 .name = "i2c_designware",
498 .of_match_table = of_match_ptr(dw_i2c_of_match),
499 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
500 .pm = DW_I2C_DEV_PMOPS,
504 static int __init dw_i2c_init_driver(void)
506 return platform_driver_register(&dw_i2c_driver);
508 subsys_initcall(dw_i2c_init_driver);
510 static void __exit dw_i2c_exit_driver(void)
512 platform_driver_unregister(&dw_i2c_driver);
514 module_exit(dw_i2c_exit_driver);
516 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
517 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
518 MODULE_LICENSE("GPL");