[PATCH 3/3] [RFC] drm/exynos: Add basic i.MX8MM support code
Michael Tretter
m.tretter at pengutronix.de
Wed Feb 3 14:53:39 EST 2021
On Mon, 05 Oct 2020 15:42:50 +0200, Marek Vasut wrote:
> This adds basic i.MX8MM glue code for the Samsung DSIM PHY.
> There are still a couple of items which need to be sorted out
> in drivers/gpu/drm/bridge/samsung-dsim.c before this can even
> be merged, specifically:
>
> - The dsi->out_bridge is not populated until samsung_dsim_host_attach()
> is called, however samsung_dsim_host_attach() is not called until the
> next bridge attaches and calls mipi_dsi_attach(), and that only happens
> after the DSIM calls drm_bridge_attach() on that next bridge.
IMO, the DSIM behaves correctly by calling drm_bridge_attach() only after
samsung_dsim_host_attach() was called. At this point some DSI device has
appeared and told the DSI host that it is the next bridge in the pipeline.
Other DRI host bridges that I looked at behave the same. Either deferring the
bridge_attach until a DSI device has attached or even adding the bridge only
after a DSI device has attached. If a DSI device behaves differently, the DSI
device should be fixed to attach during probe instead of during bridge_attach.
>
> - The samsung_dsim_bridge_mode_fixup() is needed for iMX8MM LCDIF to set
> the correct sync flags. This likely needs to be done in the glue code.
>
> Signed-off-by: Marek Vasut <marex at denx.de>
> Cc: Fabio Estevam <festevam at gmail.com>
> Cc: Guido Günther <agx at sigxcpu.org>
> Cc: Jaehoon Chung <jh80.chung at samsung.com>
> Cc: Lucas Stach <l.stach at pengutronix.de>
> Cc: Marek Szyprowski <m.szyprowski at samsung.com>
> Cc: Michael Tretter <m.tretter at pengutronix.de>
> Cc: NXP Linux Team <linux-imx at nxp.com>
> Cc: Shawn Guo <shawnguo at kernel.org>
> Cc: linux-arm-kernel at lists.infradead.org
> Cc: linux-samsung-soc at vger.kernel.org
> To: dri-devel at lists.freedesktop.org
> --
> NOTE: This depends on https://patchwork.kernel.org/project/dri-devel/list/?series=347439
> ---
> drivers/gpu/drm/bridge/Kconfig | 6 +
> drivers/gpu/drm/bridge/Makefile | 1 +
> drivers/gpu/drm/bridge/samsung-dsim-imx.c | 161 ++++++++++++++++++++++
> drivers/gpu/drm/bridge/samsung-dsim.c | 25 +++-
> 4 files changed, 192 insertions(+), 1 deletion(-)
> create mode 100644 drivers/gpu/drm/bridge/samsung-dsim-imx.c
>
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index 2d4459f78cdc..f97a8ebfcef1 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -129,6 +129,12 @@ config DRM_SAMSUNG_DSIM
> help
> Samsung MIPI DSI bridge driver.
>
> +config DRM_SAMSUNG_DSIM_IMX
> + tristate "Samsung MIPI DSI bridge extras for NXP i.MX"
> + depends on DRM_SAMSUNG_DSIM
> + help
> + Samsung MIPI DSI bridge driver extras for NXP i.MX.
> +
> config DRM_SIL_SII8620
> tristate "Silicon Image SII8620 HDMI/MHL bridge"
> depends on OF
> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> index f7972d703c5d..61188a0cd052 100644
> --- a/drivers/gpu/drm/bridge/Makefile
> +++ b/drivers/gpu/drm/bridge/Makefile
> @@ -9,6 +9,7 @@ obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o
> obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o
> obj-$(CONFIG_DRM_PARADE_PS8640) += parade-ps8640.o
> obj-$(CONFIG_DRM_SAMSUNG_DSIM) += samsung-dsim.o
> +obj-$(CONFIG_DRM_SAMSUNG_DSIM_IMX) += samsung-dsim-imx.o
> obj-$(CONFIG_DRM_SIL_SII8620) += sil-sii8620.o
> obj-$(CONFIG_DRM_SII902X) += sii902x.o
> obj-$(CONFIG_DRM_SII9234) += sii9234.o
> diff --git a/drivers/gpu/drm/bridge/samsung-dsim-imx.c b/drivers/gpu/drm/bridge/samsung-dsim-imx.c
> new file mode 100644
> index 000000000000..6c7307ce7eaf
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/samsung-dsim-imx.c
> @@ -0,0 +1,161 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * NXP i.MX8M SoC MIPI DSI driver
> + *
> + * Copyright (C) 2020 Marek Vasut <marex at denx.de>
> + */
> +
> +#include <linux/module.h>
> +#include <linux/of_device.h>
> +#include <linux/of_graph.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +
> +#include <drm/bridge/samsung-dsim.h>
> +#include <drm/drm_bridge.h>
> +#include <drm/drm_encoder.h>
> +#include <drm/drm_mipi_dsi.h>
> +#include <drm/drm_probe_helper.h>
> +#include <drm/drm_simple_kms_helper.h>
> +
> +enum {
> + DSI_PORT_IN,
> + DSI_PORT_OUT
> +};
> +
> +struct imx_dsim_priv {
> + struct samsung_dsim *dsi;
> + struct drm_encoder encoder;
> +};
> +
> +static const unsigned int imx8mm_dsim_reg_values[] = {
> + [RESET_TYPE] = DSIM_SWRST,
> + [PLL_TIMER] = 500,
> + [STOP_STATE_CNT] = 0xf,
> + [PHYCTRL_ULPS_EXIT] = 0xaf,
> + [PHYCTRL_VREG_LP] = 0,
> + [PHYCTRL_SLEW_UP] = 0,
> + [PHYTIMING_LPX] = 0x06,
> + [PHYTIMING_HS_EXIT] = 0x0b,
> + [PHYTIMING_CLK_PREPARE] = 0x07,
> + [PHYTIMING_CLK_ZERO] = 0x26,
> + [PHYTIMING_CLK_POST] = 0x0d,
> + [PHYTIMING_CLK_TRAIL] = 0x08,
> + [PHYTIMING_HS_PREPARE] = 0x08,
> + [PHYTIMING_HS_ZERO] = 0x0d,
> + [PHYTIMING_HS_TRAIL] = 0x0b,
> +};
> +
> +static int imx_dsim_host_attach(struct device *dev,
> + struct mipi_dsi_device *device)
> +{
> + struct imx_dsim_priv *dsi = dev_get_drvdata(dev);
> + struct drm_device *drm = dsi->encoder.dev;
> +
> + if (drm->mode_config.poll_enabled)
> + drm_kms_helper_hotplug_event(drm);
> +
> + return 0;
> +}
> +
> +static int imx_dsim_host_detach(struct device *dev,
> + struct mipi_dsi_device *device)
> +{
> + struct imx_dsim_priv *dsi = dev_get_drvdata(dev);
> + struct drm_device *drm = dsi->encoder.dev;
> +
> + if (drm->mode_config.poll_enabled)
> + drm_kms_helper_hotplug_event(drm);
> +
> + return 0;
> +}
> +
> +static const struct samsung_dsim_host_ops imx_dsim_host_ops = {
> + .attach = imx_dsim_host_attach,
> + .detach = imx_dsim_host_detach,
> +};
> +
> +static const struct samsung_dsim_driver_data imx8mm_dsi_driver_data = {
> + .reg_ofs = EXYNOS5433_REG_OFS,
> + .plltmr_reg = 0xa0,
> + .has_clklane_stop = 1,
> + .num_clks = 2,
> + .max_freq = 2100,
> + .wait_for_reset = 0,
> + .num_bits_resol = 12,
> + .reg_values = imx8mm_dsim_reg_values,
> + .host_ops = &imx_dsim_host_ops,
> +};
> +
> +static const struct of_device_id imx_dsim_of_match[] = {
> + { .compatible = "fsl,imx8mm-mipi-dsim",
> + .data = &imx8mm_dsi_driver_data },
> + { }
> +};
> +
> +static int imx_dsim_probe(struct platform_device *pdev)
> +{
> + struct imx_dsim_priv *dsi;
> + struct device *dev = &pdev->dev;
> +
> + dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
> + if (!dsi)
> + return -ENOMEM;
> + platform_set_drvdata(pdev, dsi);
> +
> + dsi->dsi = samsung_dsim_probe(pdev);
> + if (IS_ERR(dsi->dsi))
> + return PTR_ERR(dsi->dsi);
> +
> + pm_runtime_enable(dev);
> +
> + return 0;
> +}
> +
> +static int imx_dsim_remove(struct platform_device *pdev)
> +{
> + struct imx_dsim_priv *dsi = platform_get_drvdata(pdev);
> +
> + pm_runtime_disable(&pdev->dev);
> +
> + samsung_dsim_remove(dsi->dsi);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused imx_dsim_suspend(struct device *dev)
> +{
> + struct imx_dsim_priv *dsi = dev_get_drvdata(dev);
> +
> + return samsung_dsim_suspend(dsi->dsi);
> +}
> +
> +static int __maybe_unused imx_dsim_resume(struct device *dev)
> +{
> + struct imx_dsim_priv *dsi = dev_get_drvdata(dev);
> +
> + return samsung_dsim_resume(dsi->dsi);
> +}
> +
> +static const struct dev_pm_ops imx_dsim_pm_ops = {
> + SET_RUNTIME_PM_OPS(imx_dsim_suspend, imx_dsim_resume, NULL)
> + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> + pm_runtime_force_resume)
> +};
> +
> +static struct platform_driver imx_dsim_driver = {
> + .probe = imx_dsim_probe,
> + .remove = imx_dsim_remove,
> + .driver = {
> + .name = "imx-dsim-dsi",
> + .owner = THIS_MODULE,
> + .pm = &imx_dsim_pm_ops,
> + .of_match_table = imx_dsim_of_match,
> + },
> +};
> +
> +module_platform_driver(imx_dsim_driver);
> +
> +MODULE_AUTHOR("Marek Vasut <marex at denx.de>");
> +MODULE_DESCRIPTION("NXP i.MX8M SoC MIPI DSI");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c
> index 42b49546dd00..12aeceb40450 100644
> --- a/drivers/gpu/drm/bridge/samsung-dsim.c
> +++ b/drivers/gpu/drm/bridge/samsung-dsim.c
> @@ -28,6 +28,7 @@
> #include <drm/drm_bridge.h>
> #include <drm/drm_fb_helper.h>
> #include <drm/drm_mipi_dsi.h>
> +#include <drm/drm_of.h>
> #include <drm/drm_panel.h>
> #include <drm/drm_print.h>
> #include <drm/drm_probe_helper.h>
> @@ -1388,8 +1389,15 @@ static int samsung_dsim_bridge_attach(struct drm_bridge *bridge,
> {
> struct samsung_dsim *dsi = bridge->driver_private;
> struct drm_encoder *encoder = bridge->encoder;
> + struct device *dev = dsi->dev;
> + struct device_node *np = dev->of_node;
> int ret;
>
> + ret = drm_of_find_panel_or_bridge(np, 1, 0,
> + &dsi->panel, &dsi->out_bridge);
> + if (ret)
> + return ret;
> +
> if (!dsi->out_bridge && !dsi->panel)
> return -EPROBE_DEFER;
>
> @@ -1398,7 +1406,6 @@ static int samsung_dsim_bridge_attach(struct drm_bridge *bridge,
> bridge, flags);
> if (ret)
> return ret;
> - list_splice_init(&encoder->bridge_chain, &dsi->bridge_chain);
> } else {
> ret = samsung_dsim_create_connector(dsi);
> if (ret)
> @@ -1456,18 +1463,31 @@ static void samsung_dsim_bridge_mode_set(struct drm_bridge *bridge,
> drm_mode_copy(&dsi->mode, adjusted_mode);
> }
>
> +static bool samsung_dsim_bridge_mode_fixup(struct drm_bridge *bridge,
> + const struct drm_display_mode *mode,
> + struct drm_display_mode *adjusted_mode)
> +{
> + /* At least LCDIF + DSIM needs active low sync */
> + adjusted_mode->flags |= (DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
> + adjusted_mode->flags &= ~(DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
> +
> + return true;
> +}
> +
> static const struct drm_bridge_funcs samsung_dsim_bridge_funcs = {
> .attach = samsung_dsim_bridge_attach,
> .detach = samsung_dsim_bridge_detach,
> .enable = samsung_dsim_bridge_enable,
> .disable = samsung_dsim_bridge_disable,
> .mode_set = samsung_dsim_bridge_mode_set,
> + .mode_fixup = samsung_dsim_bridge_mode_fixup,
> };
>
> static int samsung_dsim_host_attach(struct mipi_dsi_host *host,
> struct mipi_dsi_device *device)
> {
> struct samsung_dsim *dsi = host_to_dsi(host);
> +#if 0
> const struct samsung_dsim_host_ops *ops = dsi->driver_data->host_ops;
> struct drm_bridge *out_bridge;
>
> @@ -1493,13 +1513,16 @@ static int samsung_dsim_host_attach(struct mipi_dsi_host *host,
> if (ret)
> return ret;
> }
> +#endif
>
> dsi->lanes = device->lanes;
> dsi->format = device->format;
> dsi->mode_flags = device->mode_flags;
>
> +#if 0
> if (ops && ops->attach)
> ops->attach(dsi->dsi_host.dev, device);
> +#endif
>
> return 0;
> }
> --
> 2.28.0
>
>
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