i2c-designware-amdisp.c

  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * Based on Synopsys DesignWare I2C adapter driver.
  4 *
  5 * Copyright (C) 2025 Advanced Micro Devices, Inc.
  6 */
  7
  8#include <linux/module.h>
  9#include <linux/platform_device.h>
 10#include <linux/pm_domain.h>
 11#include <linux/pm_runtime.h>
 12#include <linux/soc/amd/isp4_misc.h>
 13
 14#include "i2c-designware-core.h"
 15
 16#define DRV_NAME		"amd_isp_i2c_designware"
 17#define AMD_ISP_I2C_INPUT_CLK	100 /* Mhz */
 18
 19static void amd_isp_dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *i2c_dev)
 20{
 21	pm_runtime_disable(i2c_dev->dev);
 22
 23	if (i2c_dev->shared_with_punit)
 24		pm_runtime_put_noidle(i2c_dev->dev);
 25}
 26
 27static inline u32 amd_isp_dw_i2c_get_clk_rate(struct dw_i2c_dev *i2c_dev)
 28{
 29	return AMD_ISP_I2C_INPUT_CLK * 1000;
 30}
 31
 32static int amd_isp_dw_i2c_plat_probe(struct platform_device *pdev)
 33{
 34	struct dw_i2c_dev *isp_i2c_dev;
 35	struct i2c_adapter *adap;
 36	int ret;
 37
 38	isp_i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*isp_i2c_dev), GFP_KERNEL);
 39	if (!isp_i2c_dev)
 40		return -ENOMEM;
 41	isp_i2c_dev->dev = &pdev->dev;
 42
 43	pdev->dev.init_name = DRV_NAME;
 44
 45	/*
 46	 * Use the polling mode to send/receive the data, because
 47	 * no IRQ connection from ISP I2C
 48	 */
 49	isp_i2c_dev->flags |= ACCESS_POLLING;
 50	platform_set_drvdata(pdev, isp_i2c_dev);
 51
 52	isp_i2c_dev->base = devm_platform_ioremap_resource(pdev, 0);
 53	if (IS_ERR(isp_i2c_dev->base))
 54		return dev_err_probe(&pdev->dev, PTR_ERR(isp_i2c_dev->base),
 55				     "failed to get IOMEM resource\n");
 56
 57	isp_i2c_dev->get_clk_rate_khz = amd_isp_dw_i2c_get_clk_rate;
 58	ret = i2c_dw_fw_parse_and_configure(isp_i2c_dev);
 59	if (ret)
 60		return dev_err_probe(&pdev->dev, ret,
 61				     "failed to parse i2c dw fwnode and configure\n");
 62
 63	i2c_dw_configure(isp_i2c_dev);
 64
 65	adap = &isp_i2c_dev->adapter;
 66	adap->owner = THIS_MODULE;
 67	scnprintf(adap->name, sizeof(adap->name), AMDISP_I2C_ADAP_NAME);
 68	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
 69	adap->dev.of_node = pdev->dev.of_node;
 70	/* use dynamically allocated adapter id */
 71	adap->nr = -1;
 72
 73	if (isp_i2c_dev->flags & ACCESS_NO_IRQ_SUSPEND)
 74		dev_pm_set_driver_flags(&pdev->dev,
 75					DPM_FLAG_SMART_PREPARE);
 76	else
 77		dev_pm_set_driver_flags(&pdev->dev,
 78					DPM_FLAG_SMART_PREPARE |
 79					DPM_FLAG_SMART_SUSPEND);
 80
 81	device_enable_async_suspend(&pdev->dev);
 82
 83	if (isp_i2c_dev->shared_with_punit)
 84		pm_runtime_get_noresume(&pdev->dev);
 85
 86	dev_pm_genpd_resume(&pdev->dev);
 87	ret = i2c_dw_probe(isp_i2c_dev);
 88	if (ret) {
 89		dev_err_probe(&pdev->dev, ret, "i2c_dw_probe failed\n");
 90		goto error_release_rpm;
 91	}
 92	dev_pm_genpd_suspend(&pdev->dev);
 93	pm_runtime_set_suspended(&pdev->dev);
 94	pm_runtime_enable(&pdev->dev);
 95
 96	return 0;
 97
 98error_release_rpm:
 99	amd_isp_dw_i2c_plat_pm_cleanup(isp_i2c_dev);
100	return ret;
101}
102
103static void amd_isp_dw_i2c_plat_remove(struct platform_device *pdev)
104{
105	struct dw_i2c_dev *isp_i2c_dev = platform_get_drvdata(pdev);
106
107	pm_runtime_get_sync(&pdev->dev);
108
109	i2c_del_adapter(&isp_i2c_dev->adapter);
110
111	i2c_dw_disable(isp_i2c_dev);
112
113	pm_runtime_put_sync(&pdev->dev);
114	amd_isp_dw_i2c_plat_pm_cleanup(isp_i2c_dev);
115}
116
117static int amd_isp_dw_i2c_plat_prepare(struct device *dev)
118{
119	/*
120	 * If the ACPI companion device object is present for this device, it
121	 * may be accessed during suspend and resume of other devices via I2C
122	 * operation regions, so tell the PM core and middle layers to avoid
123	 * skipping system suspend/resume callbacks for it in that case.
124	 */
125	return !has_acpi_companion(dev);
126}
127
128static int amd_isp_dw_i2c_plat_runtime_suspend(struct device *dev)
129{
130	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
131
132	if (i_dev->shared_with_punit)
133		return 0;
134
135	i2c_dw_disable(i_dev);
136	i2c_dw_prepare_clk(i_dev, false);
137
138	return 0;
139}
140
141static int amd_isp_dw_i2c_plat_suspend(struct device *dev)
142{
143	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
144	int ret;
145
146	if (!i_dev)
147		return -ENODEV;
148
149	ret = amd_isp_dw_i2c_plat_runtime_suspend(dev);
150	if (!ret)
151		i2c_mark_adapter_suspended(&i_dev->adapter);
152
153	return ret;
154}
155
156static int amd_isp_dw_i2c_plat_runtime_resume(struct device *dev)
157{
158	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
159
160	if (!i_dev)
161		return -ENODEV;
162
163	if (!i_dev->shared_with_punit)
164		i2c_dw_prepare_clk(i_dev, true);
165	if (i_dev->init)
166		i_dev->init(i_dev);
167
168	return 0;
169}
170
171static int amd_isp_dw_i2c_plat_resume(struct device *dev)
172{
173	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
174
175	amd_isp_dw_i2c_plat_runtime_resume(dev);
176	i2c_mark_adapter_resumed(&i_dev->adapter);
177
178	return 0;
179}
180
181static const struct dev_pm_ops amd_isp_dw_i2c_dev_pm_ops = {
182	.prepare = pm_sleep_ptr(amd_isp_dw_i2c_plat_prepare),
183	LATE_SYSTEM_SLEEP_PM_OPS(amd_isp_dw_i2c_plat_suspend, amd_isp_dw_i2c_plat_resume)
184	RUNTIME_PM_OPS(amd_isp_dw_i2c_plat_runtime_suspend, amd_isp_dw_i2c_plat_runtime_resume, NULL)
185};
186
187/* Work with hotplug and coldplug */
188MODULE_ALIAS("platform:amd_isp_i2c_designware");
189
190static struct platform_driver amd_isp_dw_i2c_driver = {
191	.probe = amd_isp_dw_i2c_plat_probe,
192	.remove = amd_isp_dw_i2c_plat_remove,
193	.driver		= {
194		.name	= DRV_NAME,
195		.pm	= pm_ptr(&amd_isp_dw_i2c_dev_pm_ops),
196	},
197};
198module_platform_driver(amd_isp_dw_i2c_driver);
199
200MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter in AMD ISP");
201MODULE_IMPORT_NS("I2C_DW");
202MODULE_IMPORT_NS("I2C_DW_COMMON");
203MODULE_AUTHOR("Venkata Narendra Kumar Gutta <vengutta@amd.com>");
204MODULE_AUTHOR("Pratap Nirujogi <pratap.nirujogi@amd.com>");
205MODULE_AUTHOR("Bin Du <bin.du@amd.com>");
206MODULE_LICENSE("GPL");