diff options
Diffstat (limited to 'drivers/media/platform/exynos4-is/fimc-is-i2c.c')
| -rw-r--r-- | drivers/media/platform/exynos4-is/fimc-is-i2c.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/drivers/media/platform/exynos4-is/fimc-is-i2c.c b/drivers/media/platform/exynos4-is/fimc-is-i2c.c new file mode 100644 index 000000000..70dd4852b --- /dev/null +++ b/drivers/media/platform/exynos4-is/fimc-is-i2c.c @@ -0,0 +1,162 @@ +/* + * Samsung EXYNOS4x12 FIMC-IS (Imaging Subsystem) driver + * + * Copyright (C) 2013 Samsung Electronics Co., Ltd. + * + * Author: Sylwester Nawrocki <s.nawrocki@samsung.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/clk.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/platform_device.h> +#include <linux/pm_runtime.h> +#include <linux/slab.h> +#include "fimc-is-i2c.h" + +struct fimc_is_i2c { + struct i2c_adapter adapter; + struct clk *clock; +}; + +/* + * An empty algorithm is used as the actual I2C bus controller driver + * is implemented in the FIMC-IS subsystem firmware and the host CPU + * doesn't access the I2C bus controller. + */ +static u32 is_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C; +} + +static const struct i2c_algorithm fimc_is_i2c_algorithm = { + .functionality = is_i2c_func, +}; + +static int fimc_is_i2c_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct fimc_is_i2c *isp_i2c; + struct i2c_adapter *i2c_adap; + int ret; + + isp_i2c = devm_kzalloc(&pdev->dev, sizeof(*isp_i2c), GFP_KERNEL); + if (!isp_i2c) + return -ENOMEM; + + isp_i2c->clock = devm_clk_get(&pdev->dev, "i2c_isp"); + if (IS_ERR(isp_i2c->clock)) { + dev_err(&pdev->dev, "failed to get the clock\n"); + return PTR_ERR(isp_i2c->clock); + } + + i2c_adap = &isp_i2c->adapter; + i2c_adap->dev.of_node = node; + i2c_adap->dev.parent = &pdev->dev; + strlcpy(i2c_adap->name, "exynos4x12-isp-i2c", sizeof(i2c_adap->name)); + i2c_adap->owner = THIS_MODULE; + i2c_adap->algo = &fimc_is_i2c_algorithm; + i2c_adap->class = I2C_CLASS_SPD; + + platform_set_drvdata(pdev, isp_i2c); + pm_runtime_enable(&pdev->dev); + + ret = i2c_add_adapter(i2c_adap); + if (ret < 0) + goto err_pm_dis; + /* + * Client drivers of this adapter don't do any I2C transfers as that + * is handled by the ISP firmware. But we rely on the runtime PM + * state propagation from the clients up to the adapter driver so + * clear the ignore_children flags here. PM rutnime calls are not + * used in probe() handler of clients of this adapter so there is + * no issues with clearing the flag right after registering the I2C + * adapter. + */ + pm_suspend_ignore_children(&i2c_adap->dev, false); + return 0; + +err_pm_dis: + pm_runtime_disable(&pdev->dev); + return ret; +} + +static int fimc_is_i2c_remove(struct platform_device *pdev) +{ + struct fimc_is_i2c *isp_i2c = platform_get_drvdata(pdev); + + pm_runtime_disable(&pdev->dev); + i2c_del_adapter(&isp_i2c->adapter); + + return 0; +} + +#ifdef CONFIG_PM +static int fimc_is_i2c_runtime_suspend(struct device *dev) +{ + struct fimc_is_i2c *isp_i2c = dev_get_drvdata(dev); + + clk_disable_unprepare(isp_i2c->clock); + return 0; +} + +static int fimc_is_i2c_runtime_resume(struct device *dev) +{ + struct fimc_is_i2c *isp_i2c = dev_get_drvdata(dev); + + return clk_prepare_enable(isp_i2c->clock); +} +#endif + +#ifdef CONFIG_PM_SLEEP +static int fimc_is_i2c_suspend(struct device *dev) +{ + if (pm_runtime_suspended(dev)) + return 0; + + return fimc_is_i2c_runtime_suspend(dev); +} + +static int fimc_is_i2c_resume(struct device *dev) +{ + if (pm_runtime_suspended(dev)) + return 0; + + return fimc_is_i2c_runtime_resume(dev); +} +#endif + +static const struct dev_pm_ops fimc_is_i2c_pm_ops = { + SET_RUNTIME_PM_OPS(fimc_is_i2c_runtime_suspend, + fimc_is_i2c_runtime_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(fimc_is_i2c_suspend, fimc_is_i2c_resume) +}; + +static const struct of_device_id fimc_is_i2c_of_match[] = { + { .compatible = FIMC_IS_I2C_COMPATIBLE }, + { }, +}; + +static struct platform_driver fimc_is_i2c_driver = { + .probe = fimc_is_i2c_probe, + .remove = fimc_is_i2c_remove, + .driver = { + .of_match_table = fimc_is_i2c_of_match, + .name = "fimc-isp-i2c", + .pm = &fimc_is_i2c_pm_ops, + } +}; + +int fimc_is_register_i2c_driver(void) +{ + return platform_driver_register(&fimc_is_i2c_driver); +} + +void fimc_is_unregister_i2c_driver(void) +{ + platform_driver_unregister(&fimc_is_i2c_driver); +} |