From 179b0769fc5fc193d7837bdcb6ddee118a0fa9b8 Mon Sep 17 00:00:00 2001 From: Dharma Balasubiramani Date: Sun, 21 Apr 2024 06:40:48 +0530 Subject: drm/bridge: add lvds controller support for sam9x7 Add a new LVDS controller driver for sam9x7 which does the following: - Prepares and enables the LVDS Peripheral clock - Defines its connector type as DRM_MODE_CONNECTOR_LVDS and adds itself to the global bridge list. - Identifies its output endpoint as panel and adds it to the encoder display pipeline - Enables the LVDS serializer Signed-off-by: Manikandan Muralidharan Signed-off-by: Dharma Balasubiramani Acked-by: Hari Prasath Gujulan Elango Reviewed-by: Dmitry Baryshkov Link: https://lore.kernel.org/r/20240421011050.43265-3-dharma.b@microchip.com Signed-off-by: Neil Armstrong Link: https://patchwork.freedesktop.org/patch/msgid/20240421011050.43265-3-dharma.b@microchip.com --- drivers/gpu/drm/bridge/Kconfig | 7 + drivers/gpu/drm/bridge/Makefile | 1 + drivers/gpu/drm/bridge/microchip-lvds.c | 229 ++++++++++++++++++++++++++++++++ 3 files changed, 237 insertions(+) create mode 100644 drivers/gpu/drm/bridge/microchip-lvds.c diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig index d1fbf8796fea..30a17876ff50 100644 --- a/drivers/gpu/drm/bridge/Kconfig +++ b/drivers/gpu/drm/bridge/Kconfig @@ -189,6 +189,13 @@ config DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW to DP++. This is used with the i.MX6 imx-ldb driver. You are likely to say N here. +config DRM_MICROCHIP_LVDS_SERIALIZER + tristate "Microchip LVDS serializer support" + depends on OF + depends on DRM_ATMEL_HLCDC + help + Support for Microchip's LVDS serializer. + config DRM_NWL_MIPI_DSI tristate "Northwest Logic MIPI DSI Host controller" depends on DRM diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile index 017b5832733b..7df87b582dca 100644 --- a/drivers/gpu/drm/bridge/Makefile +++ b/drivers/gpu/drm/bridge/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_DRM_LONTIUM_LT9611) += lontium-lt9611.o obj-$(CONFIG_DRM_LONTIUM_LT9611UXC) += lontium-lt9611uxc.o obj-$(CONFIG_DRM_LVDS_CODEC) += lvds-codec.o obj-$(CONFIG_DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW) += megachips-stdpxxxx-ge-b850v3-fw.o +obj-$(CONFIG_DRM_MICROCHIP_LVDS_SERIALIZER) += microchip-lvds.o obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o obj-$(CONFIG_DRM_PARADE_PS8640) += parade-ps8640.o diff --git a/drivers/gpu/drm/bridge/microchip-lvds.c b/drivers/gpu/drm/bridge/microchip-lvds.c new file mode 100644 index 000000000000..b8313dad6072 --- /dev/null +++ b/drivers/gpu/drm/bridge/microchip-lvds.c @@ -0,0 +1,229 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2023 Microchip Technology Inc. and its subsidiaries + * + * Author: Manikandan Muralidharan + * Author: Dharma Balasubiramani + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include + +#define LVDS_POLL_TIMEOUT_MS 1000 + +/* LVDSC register offsets */ +#define LVDSC_CR 0x00 +#define LVDSC_CFGR 0x04 +#define LVDSC_SR 0x0C +#define LVDSC_WPMR 0xE4 + +/* Bitfields in LVDSC_CR (Control Register) */ +#define LVDSC_CR_SER_EN BIT(0) + +/* Bitfields in LVDSC_CFGR (Configuration Register) */ +#define LVDSC_CFGR_PIXSIZE_24BITS 0 +#define LVDSC_CFGR_DEN_POL_HIGH 0 +#define LVDSC_CFGR_DC_UNBALANCED 0 +#define LVDSC_CFGR_MAPPING_JEIDA BIT(6) + +/*Bitfields in LVDSC_SR */ +#define LVDSC_SR_CS BIT(0) + +/* Bitfields in LVDSC_WPMR (Write Protection Mode Register) */ +#define LVDSC_WPMR_WPKEY_MASK GENMASK(31, 8) +#define LVDSC_WPMR_WPKEY_PSSWD 0x4C5644 + +struct mchp_lvds { + struct device *dev; + void __iomem *regs; + struct clk *pclk; + struct drm_panel *panel; + struct drm_bridge bridge; + struct drm_bridge *panel_bridge; +}; + +static inline struct mchp_lvds *bridge_to_lvds(struct drm_bridge *bridge) +{ + return container_of(bridge, struct mchp_lvds, bridge); +} + +static inline u32 lvds_readl(struct mchp_lvds *lvds, u32 offset) +{ + return readl_relaxed(lvds->regs + offset); +} + +static inline void lvds_writel(struct mchp_lvds *lvds, u32 offset, u32 val) +{ + writel_relaxed(val, lvds->regs + offset); +} + +static void lvds_serialiser_on(struct mchp_lvds *lvds) +{ + unsigned long timeout = jiffies + msecs_to_jiffies(LVDS_POLL_TIMEOUT_MS); + + /* The LVDSC registers can only be written if WPEN is cleared */ + lvds_writel(lvds, LVDSC_WPMR, (LVDSC_WPMR_WPKEY_PSSWD & + LVDSC_WPMR_WPKEY_MASK)); + + /* Wait for the status of configuration registers to be changed */ + while (lvds_readl(lvds, LVDSC_SR) & LVDSC_SR_CS) { + if (time_after(jiffies, timeout)) { + dev_err(lvds->dev, "%s: timeout error\n", __func__); + return; + } + usleep_range(1000, 2000); + } + + /* Configure the LVDSC */ + lvds_writel(lvds, LVDSC_CFGR, (LVDSC_CFGR_MAPPING_JEIDA | + LVDSC_CFGR_DC_UNBALANCED | + LVDSC_CFGR_DEN_POL_HIGH | + LVDSC_CFGR_PIXSIZE_24BITS)); + + /* Enable the LVDS serializer */ + lvds_writel(lvds, LVDSC_CR, LVDSC_CR_SER_EN); +} + +static int mchp_lvds_attach(struct drm_bridge *bridge, + enum drm_bridge_attach_flags flags) +{ + struct mchp_lvds *lvds = bridge_to_lvds(bridge); + + return drm_bridge_attach(bridge->encoder, lvds->panel_bridge, + bridge, flags); +} + +static void mchp_lvds_enable(struct drm_bridge *bridge) +{ + struct mchp_lvds *lvds = bridge_to_lvds(bridge); + int ret; + + ret = clk_prepare_enable(lvds->pclk); + if (ret < 0) { + dev_err(lvds->dev, "failed to enable lvds pclk %d\n", ret); + return; + } + + ret = pm_runtime_get_sync(lvds->dev); + if (ret < 0) { + dev_err(lvds->dev, "failed to get pm runtime: %d\n", ret); + return; + } + + lvds_serialiser_on(lvds); +} + +static void mchp_lvds_disable(struct drm_bridge *bridge) +{ + struct mchp_lvds *lvds = bridge_to_lvds(bridge); + + pm_runtime_put(lvds->dev); + clk_disable_unprepare(lvds->pclk); +} + +static const struct drm_bridge_funcs mchp_lvds_bridge_funcs = { + .attach = mchp_lvds_attach, + .enable = mchp_lvds_enable, + .disable = mchp_lvds_disable, +}; + +static int mchp_lvds_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct mchp_lvds *lvds; + struct device_node *port; + int ret; + + if (!dev->of_node) + return -ENODEV; + + lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL); + if (!lvds) + return -ENOMEM; + + lvds->dev = dev; + + lvds->regs = devm_ioremap_resource(lvds->dev, + platform_get_resource(pdev, IORESOURCE_MEM, 0)); + if (IS_ERR(lvds->regs)) + return PTR_ERR(lvds->regs); + + lvds->pclk = devm_clk_get(lvds->dev, "pclk"); + if (IS_ERR(lvds->pclk)) + return dev_err_probe(lvds->dev, PTR_ERR(lvds->pclk), + "could not get pclk_lvds\n"); + + port = of_graph_get_remote_node(dev->of_node, 1, 0); + if (!port) { + dev_err(dev, + "can't find port point, please init lvds panel port!\n"); + return -ENODEV; + } + + lvds->panel = of_drm_find_panel(port); + of_node_put(port); + + if (IS_ERR(lvds->panel)) + return -EPROBE_DEFER; + + lvds->panel_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0); + + if (IS_ERR(lvds->panel_bridge)) + return PTR_ERR(lvds->panel_bridge); + + lvds->bridge.of_node = dev->of_node; + lvds->bridge.type = DRM_MODE_CONNECTOR_LVDS; + lvds->bridge.funcs = &mchp_lvds_bridge_funcs; + + dev_set_drvdata(dev, lvds); + ret = devm_pm_runtime_enable(dev); + if (ret < 0) { + dev_err(lvds->dev, "failed to enable pm runtime: %d\n", ret); + return ret; + } + + drm_bridge_add(&lvds->bridge); + + return 0; +} + +static const struct of_device_id mchp_lvds_dt_ids[] = { + { + .compatible = "microchip,sam9x75-lvds", + }, + {}, +}; +MODULE_DEVICE_TABLE(of, mchp_lvds_dt_ids); + +static struct platform_driver mchp_lvds_driver = { + .probe = mchp_lvds_probe, + .driver = { + .name = "microchip-lvds", + .of_match_table = mchp_lvds_dt_ids, + }, +}; +module_platform_driver(mchp_lvds_driver); + +MODULE_AUTHOR("Manikandan Muralidharan "); +MODULE_AUTHOR("Dharma Balasubiramani "); +MODULE_DESCRIPTION("Low Voltage Differential Signaling Controller Driver"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3