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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Samsung EXYNOS4x12 FIMC-IS (Imaging Subsystem) driver4 *5 * Copyright (C) 2013 Samsung Electronics Co., Ltd.6 *7 * Author: Sylwester Nawrocki <s.nawrocki@samsung.com>8 */9 10#include <linux/clk.h>11#include <linux/module.h>12#include <linux/i2c.h>13#include <linux/platform_device.h>14#include <linux/pm_runtime.h>15#include <linux/slab.h>16#include "fimc-is-i2c.h"17 18struct fimc_is_i2c {19 struct i2c_adapter adapter;20 struct clk *clock;21};22 23/*24 * An empty algorithm is used as the actual I2C bus controller driver25 * is implemented in the FIMC-IS subsystem firmware and the host CPU26 * doesn't access the I2C bus controller.27 */28static u32 is_i2c_func(struct i2c_adapter *adap)29{30 return I2C_FUNC_I2C;31}32 33static const struct i2c_algorithm fimc_is_i2c_algorithm = {34 .functionality = is_i2c_func,35};36 37static int fimc_is_i2c_probe(struct platform_device *pdev)38{39 struct device_node *node = pdev->dev.of_node;40 struct fimc_is_i2c *isp_i2c;41 struct i2c_adapter *i2c_adap;42 int ret;43 44 isp_i2c = devm_kzalloc(&pdev->dev, sizeof(*isp_i2c), GFP_KERNEL);45 if (!isp_i2c)46 return -ENOMEM;47 48 isp_i2c->clock = devm_clk_get(&pdev->dev, "i2c_isp");49 if (IS_ERR(isp_i2c->clock)) {50 dev_err(&pdev->dev, "failed to get the clock\n");51 return PTR_ERR(isp_i2c->clock);52 }53 54 i2c_adap = &isp_i2c->adapter;55 i2c_adap->dev.of_node = node;56 i2c_adap->dev.parent = &pdev->dev;57 strscpy(i2c_adap->name, "exynos4x12-isp-i2c", sizeof(i2c_adap->name));58 i2c_adap->owner = THIS_MODULE;59 i2c_adap->algo = &fimc_is_i2c_algorithm;60 61 platform_set_drvdata(pdev, isp_i2c);62 pm_runtime_enable(&pdev->dev);63 64 ret = i2c_add_adapter(i2c_adap);65 if (ret < 0)66 goto err_pm_dis;67 /*68 * Client drivers of this adapter don't do any I2C transfers as that69 * is handled by the ISP firmware. But we rely on the runtime PM70 * state propagation from the clients up to the adapter driver so71 * clear the ignore_children flags here. PM rutnime calls are not72 * used in probe() handler of clients of this adapter so there is73 * no issues with clearing the flag right after registering the I2C74 * adapter.75 */76 pm_suspend_ignore_children(&i2c_adap->dev, false);77 return 0;78 79err_pm_dis:80 pm_runtime_disable(&pdev->dev);81 return ret;82}83 84static void fimc_is_i2c_remove(struct platform_device *pdev)85{86 struct fimc_is_i2c *isp_i2c = platform_get_drvdata(pdev);87 88 pm_runtime_disable(&pdev->dev);89 i2c_del_adapter(&isp_i2c->adapter);90}91 92#ifdef CONFIG_PM93static int fimc_is_i2c_runtime_suspend(struct device *dev)94{95 struct fimc_is_i2c *isp_i2c = dev_get_drvdata(dev);96 97 clk_disable_unprepare(isp_i2c->clock);98 return 0;99}100 101static int fimc_is_i2c_runtime_resume(struct device *dev)102{103 struct fimc_is_i2c *isp_i2c = dev_get_drvdata(dev);104 105 return clk_prepare_enable(isp_i2c->clock);106}107#endif108 109#ifdef CONFIG_PM_SLEEP110static int fimc_is_i2c_suspend(struct device *dev)111{112 if (pm_runtime_suspended(dev))113 return 0;114 115 return fimc_is_i2c_runtime_suspend(dev);116}117 118static int fimc_is_i2c_resume(struct device *dev)119{120 if (pm_runtime_suspended(dev))121 return 0;122 123 return fimc_is_i2c_runtime_resume(dev);124}125#endif126 127static const struct dev_pm_ops fimc_is_i2c_pm_ops = {128 SET_RUNTIME_PM_OPS(fimc_is_i2c_runtime_suspend,129 fimc_is_i2c_runtime_resume, NULL)130 SET_SYSTEM_SLEEP_PM_OPS(fimc_is_i2c_suspend, fimc_is_i2c_resume)131};132 133static const struct of_device_id fimc_is_i2c_of_match[] = {134 { .compatible = FIMC_IS_I2C_COMPATIBLE },135 { },136};137 138static struct platform_driver fimc_is_i2c_driver = {139 .probe = fimc_is_i2c_probe,140 .remove_new = fimc_is_i2c_remove,141 .driver = {142 .of_match_table = fimc_is_i2c_of_match,143 .name = "fimc-isp-i2c",144 .pm = &fimc_is_i2c_pm_ops,145 }146};147 148int fimc_is_register_i2c_driver(void)149{150 return platform_driver_register(&fimc_is_i2c_driver);151}152 153void fimc_is_unregister_i2c_driver(void)154{155 platform_driver_unregister(&fimc_is_i2c_driver);156}157