diff options
| -rw-r--r-- | Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt | 24 | ||||
| -rw-r--r-- | drivers/gpu/drm/sun4i/Makefile | 2 | ||||
| -rw-r--r-- | drivers/gpu/drm/sun4i/sun6i_drc.c | 118 |
3 files changed, 143 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt index abe9e9d..b95696d 100644 --- a/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt +++ b/Documentation/devicetree/bindings/display/sunxi/sun4i-drm.txt @@ -53,6 +53,30 @@ Required properties: On the A13, there is one more clock required: - 'tcon-ch1': The clock driving the TCON channel 1 +DRC +--- + +The DRC (Dynamic Range Controller), found in the latest Allwinner SoCs +(A31, A23, A33), allows to dynamically adjust pixel +brightness/contrast based on histogram measurements for LCD content +adaptive backlight control. + + +Required properties: + - compatible: value must be one of: + * allwinner,sun8i-a33-drc + - reg: base address and size of the memory-mapped region. + - interrupts: interrupt associated to this IP + - clocks: phandles to the clocks feeding the DRC + * ahb: the DRC interface clock + * mod: the DRC module clock + * ram: the DRC DRAM clock + - clock-names: the clock names mentioned above + - resets: phandles to the reset line driving the DRC + +- ports: A ports node with endpoint definitions as defined in + Documentation/devicetree/bindings/media/video-interfaces.txt. The + first port should be the input endpoints, the second one the outputs Display Engine Backend ---------------------- diff --git a/drivers/gpu/drm/sun4i/Makefile b/drivers/gpu/drm/sun4i/Makefile index 58cd551..d625a82 100644 --- a/drivers/gpu/drm/sun4i/Makefile +++ b/drivers/gpu/drm/sun4i/Makefile @@ -9,5 +9,5 @@ sun4i-tcon-y += sun4i_dotclock.o obj-$(CONFIG_DRM_SUN4I) += sun4i-drm.o sun4i-tcon.o obj-$(CONFIG_DRM_SUN4I) += sun4i_backend.o - +obj-$(CONFIG_DRM_SUN4I) += sun6i_drc.o obj-$(CONFIG_DRM_SUN4I) += sun4i_tv.o diff --git a/drivers/gpu/drm/sun4i/sun6i_drc.c b/drivers/gpu/drm/sun4i/sun6i_drc.c new file mode 100644 index 0000000..bf6d846 --- /dev/null +++ b/drivers/gpu/drm/sun4i/sun6i_drc.c @@ -0,0 +1,118 @@ +/* + * Copyright (C) 2016 Free Electrons + * + * Maxime Ripard <maxime.ripard@free-electrons.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + */ + +#include <linux/clk.h> +#include <linux/component.h> +#include <linux/module.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; + } + 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_disable_unprepare(drc->mod_clk); + clk_disable_unprepare(drc->bus_clk); + reset_control_assert(drc->reset); +} + +static 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,sun8i-a33-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"); |