diff options
Diffstat (limited to 'drivers/gpu/drm/sun4i/sun6i_drc.c')
| -rw-r--r-- | drivers/gpu/drm/sun4i/sun6i_drc.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/drivers/gpu/drm/sun4i/sun6i_drc.c b/drivers/gpu/drm/sun4i/sun6i_drc.c new file mode 100644 index 000000000..4fbe9a6b5 --- /dev/null +++ b/drivers/gpu/drm/sun4i/sun6i_drc.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2016 Free Electrons + * + * Maxime Ripard <maxime.ripard@free-electrons.com> + */ + +#include <linux/clk.h> +#include <linux/component.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/reset.h> + +struct sun6i_drc { + struct clk *bus_clk; + struct clk *mod_clk; + struct reset_control *reset; +}; + +static int sun6i_drc_bind(struct device *dev, struct device *master, + void *data) +{ + struct sun6i_drc *drc; + int ret; + + drc = devm_kzalloc(dev, sizeof(*drc), GFP_KERNEL); + if (!drc) + return -ENOMEM; + dev_set_drvdata(dev, drc); + + drc->reset = devm_reset_control_get(dev, NULL); + if (IS_ERR(drc->reset)) { + dev_err(dev, "Couldn't get our reset line\n"); + return PTR_ERR(drc->reset); + } + + ret = reset_control_deassert(drc->reset); + if (ret) { + dev_err(dev, "Couldn't deassert our reset line\n"); + return ret; + } + + drc->bus_clk = devm_clk_get(dev, "ahb"); + if (IS_ERR(drc->bus_clk)) { + dev_err(dev, "Couldn't get our bus clock\n"); + ret = PTR_ERR(drc->bus_clk); + goto err_assert_reset; + } + clk_prepare_enable(drc->bus_clk); + + drc->mod_clk = devm_clk_get(dev, "mod"); + if (IS_ERR(drc->mod_clk)) { + dev_err(dev, "Couldn't get our mod clock\n"); + ret = PTR_ERR(drc->mod_clk); + goto err_disable_bus_clk; + } + + ret = clk_set_rate_exclusive(drc->mod_clk, 300000000); + if (ret) { + dev_err(dev, "Couldn't set the module clock frequency\n"); + goto err_disable_bus_clk; + } + + clk_prepare_enable(drc->mod_clk); + + return 0; + +err_disable_bus_clk: + clk_disable_unprepare(drc->bus_clk); +err_assert_reset: + reset_control_assert(drc->reset); + return ret; +} + +static void sun6i_drc_unbind(struct device *dev, struct device *master, + void *data) +{ + struct sun6i_drc *drc = dev_get_drvdata(dev); + + clk_rate_exclusive_put(drc->mod_clk); + clk_disable_unprepare(drc->mod_clk); + clk_disable_unprepare(drc->bus_clk); + reset_control_assert(drc->reset); +} + +static const struct component_ops sun6i_drc_ops = { + .bind = sun6i_drc_bind, + .unbind = sun6i_drc_unbind, +}; + +static int sun6i_drc_probe(struct platform_device *pdev) +{ + return component_add(&pdev->dev, &sun6i_drc_ops); +} + +static int sun6i_drc_remove(struct platform_device *pdev) +{ + component_del(&pdev->dev, &sun6i_drc_ops); + + return 0; +} + +static const struct of_device_id sun6i_drc_of_table[] = { + { .compatible = "allwinner,sun6i-a31-drc" }, + { .compatible = "allwinner,sun6i-a31s-drc" }, + { .compatible = "allwinner,sun8i-a23-drc" }, + { .compatible = "allwinner,sun8i-a33-drc" }, + { .compatible = "allwinner,sun9i-a80-drc" }, + { } +}; +MODULE_DEVICE_TABLE(of, sun6i_drc_of_table); + +static struct platform_driver sun6i_drc_platform_driver = { + .probe = sun6i_drc_probe, + .remove = sun6i_drc_remove, + .driver = { + .name = "sun6i-drc", + .of_match_table = sun6i_drc_of_table, + }, +}; +module_platform_driver(sun6i_drc_platform_driver); + +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); +MODULE_DESCRIPTION("Allwinner A31 Dynamic Range Control (DRC) Driver"); +MODULE_LICENSE("GPL"); |