Re: [PATCH v6 13/14] drm/bridge: imx: Add LDB support for i.MX8qm

From: Robert Foss
Date: Wed Mar 31 2021 - 08:40:35 EST

On Wed, 31 Mar 2021 at 08:41, Liu Ying <victor.liu@xxxxxxx> wrote:
>
> Hi Robert,
>
> On Tue, 2021-03-30 at 12:05 +0200, Robert Foss wrote:
> > Hey Liu,
> >
> > checkpatch --strict lists some nits for this patch with those and the
> > below warning fixed, feel free to add my r-b.
>
> Thanks for your review.
>
> Will fix those nits in the next version.
>
> Regarding the warning you mentioned, is it the Kconfig warning?
> I'm asssuming it can also be ignored just like the one for patch 12/14?

Yes, that's correct. And I'm ok with disregarding it.

>
> Liu Ying
>
> >
> > On Wed, 17 Mar 2021 at 04:57, Liu Ying <victor.liu@xxxxxxx> wrote:
> > > This patch adds a drm bridge driver for i.MX8qm LVDS display bridge(LDB)
> > > which is officially named as pixel mapper. The LDB has two channels.
> > > Each of them supports up to 30bpp parallel input color format and can
> > > map the input to VESA or JEIDA standards. The two channels can be used
> > > simultaneously, either in dual mode or split mode. In dual mode, the
> > > two channels output identical data. In split mode, channel0 outputs
> > > odd pixels and channel1 outputs even pixels. This patch supports the
> > > LDB single mode and split mode.
> > >
> > > Signed-off-by: Liu Ying <victor.liu@xxxxxxx>
> > > ---
> > > Note that this patch depends on the patch 'phy: Add LVDS configuration options',
> > > which has already been sent with the following series to add Mixel combo PHY
> > > found in i.MX8qxp:
> > > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.spinics.net%2Flists%2Farm-kernel%2Fmsg879957.html&amp;data=04%7C01%7Cvictor.liu%40nxp.com%7C8d7bbad6a7884d28c2b108d8f3635586%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637526955256377476%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=%2FlBdn8%2FdU3tbJC5W%2B4qCIBv1UO6b8I97MnOFhOXiBy4%3D&amp;reserved=0
> > >
> > > v5->v6:
> > > * No change.
> > >
> > > v4->v5:
> > > * Link with the imx-ldb-helper object. (Robert)
> > > * Correspondingly, rename 'imx8qm-ldb.c' to 'imx8qm-ldb-drv.c'.
> > >
> > > v3->v4:
> > > * No change.
> > >
> > > v2->v3:
> > > * No change.
> > >
> > > v1->v2:
> > > * Drop unnecessary check for maximum available LDB channels.
> > > * Mention i.MX8qm LDB official name 'pixel mapper' in the bridge driver
> > > and Kconfig help message.
> > >
> > > drivers/gpu/drm/bridge/imx/Kconfig | 9 +
> > > drivers/gpu/drm/bridge/imx/Makefile | 3 +
> > > drivers/gpu/drm/bridge/imx/imx8qm-ldb-drv.c | 586 ++++++++++++++++++++++++++++
> > > 3 files changed, 598 insertions(+)
> > > create mode 100644 drivers/gpu/drm/bridge/imx/imx8qm-ldb-drv.c
> > >
> > > diff --git a/drivers/gpu/drm/bridge/imx/Kconfig b/drivers/gpu/drm/bridge/imx/Kconfig
> > > index 94f8db4d..3a8683f 100644
> > > --- a/drivers/gpu/drm/bridge/imx/Kconfig
> > > +++ b/drivers/gpu/drm/bridge/imx/Kconfig
> > > @@ -1,3 +1,12 @@
> > > +config DRM_IMX8QM_LDB
> > > + tristate "Freescale i.MX8QM LVDS display bridge"
> > > + depends on OF
> > > + depends on COMMON_CLK
> > > + select DRM_KMS_HELPER
> > > + help
> > > + Choose this to enable the internal LVDS Display Bridge(LDB) found in
> > > + Freescale i.MX8qm processor. Official name of LDB is pixel mapper.
> > > +
> > > config DRM_IMX8QXP_LDB
> > > tristate "Freescale i.MX8QXP LVDS display bridge"
> > > depends on OF
> > > diff --git a/drivers/gpu/drm/bridge/imx/Makefile b/drivers/gpu/drm/bridge/imx/Makefile
> > > index 96d5d1e..aa90ec8 100644
> > > --- a/drivers/gpu/drm/bridge/imx/Makefile
> > > +++ b/drivers/gpu/drm/bridge/imx/Makefile
> > > @@ -1,3 +1,6 @@
> > > +imx8qm-ldb-objs := imx-ldb-helper.o imx8qm-ldb-drv.o
> > > +obj-$(CONFIG_DRM_IMX8QM_LDB) += imx8qm-ldb.o
> > > +
> > > imx8qxp-ldb-objs := imx-ldb-helper.o imx8qxp-ldb-drv.o
> > > obj-$(CONFIG_DRM_IMX8QXP_LDB) += imx8qxp-ldb.o
> > >
> > > diff --git a/drivers/gpu/drm/bridge/imx/imx8qm-ldb-drv.c b/drivers/gpu/drm/bridge/imx/imx8qm-ldb-drv.c
> > > new file mode 100644
> > > index 00000000..6c92636
> > > --- /dev/null
> > > +++ b/drivers/gpu/drm/bridge/imx/imx8qm-ldb-drv.c
> > > @@ -0,0 +1,586 @@
> > > +// SPDX-License-Identifier: GPL-2.0+
> > > +
> > > +/*
> > > + * Copyright 2020 NXP
> > > + */
> > > +
> > > +#include <linux/clk.h>
> > > +#include <linux/mfd/syscon.h>
> > > +#include <linux/module.h>
> > > +#include <linux/of.h>
> > > +#include <linux/of_device.h>
> > > +#include <linux/of_graph.h>
> > > +#include <linux/phy/phy.h>
> > > +#include <linux/pm_runtime.h>
> > > +#include <linux/regmap.h>
> > > +
> > > +#include <drm/drm_atomic_state_helper.h>
> > > +#include <drm/drm_bridge.h>
> > > +#include <drm/drm_connector.h>
> > > +#include <drm/drm_fourcc.h>
> > > +#include <drm/drm_of.h>
> > > +#include <drm/drm_print.h>
> > > +
> > > +#include "imx-ldb-helper.h"
> > > +
> > > +#define LDB_CH0_10BIT_EN (1 << 22)
> > > +#define LDB_CH1_10BIT_EN (1 << 23)
> > > +#define LDB_CH0_DATA_WIDTH_24BIT (1 << 24)
> > > +#define LDB_CH1_DATA_WIDTH_24BIT (1 << 26)
> > > +#define LDB_CH0_DATA_WIDTH_30BIT (2 << 24)
> > > +#define LDB_CH1_DATA_WIDTH_30BIT (2 << 26)
> > > +
> > > +#define SS_CTRL 0x20
> > > +#define CH_HSYNC_M(id) BIT(0 + ((id) * 2))
> > > +#define CH_VSYNC_M(id) BIT(1 + ((id) * 2))
> > > +#define CH_PHSYNC(id) BIT(0 + ((id) * 2))
> > > +#define CH_PVSYNC(id) BIT(1 + ((id) * 2))
> > > +
> > > +#define DRIVER_NAME "imx8qm-ldb"
> > > +
> > > +struct imx8qm_ldb_channel {
> > > + struct ldb_channel base;
> > > + struct phy *phy;
> > > +};
> > > +
> > > +struct imx8qm_ldb {
> > > + struct ldb base;
> > > + struct device *dev;
> > > + struct imx8qm_ldb_channel channel[MAX_LDB_CHAN_NUM];
> > > + struct clk *clk_pixel;
> > > + struct clk *clk_bypass;
> > > + int active_chno;
> > > +};
> > > +
> > > +static inline struct imx8qm_ldb_channel *
> > > +base_to_imx8qm_ldb_channel(struct ldb_channel *base)
> > > +{
> > > + return container_of(base, struct imx8qm_ldb_channel, base);
> > > +}
> > > +
> > > +static inline struct imx8qm_ldb *base_to_imx8qm_ldb(struct ldb *base)
> > > +{
> > > + return container_of(base, struct imx8qm_ldb, base);
> > > +}
> > > +
> > > +static void imx8qm_ldb_set_phy_cfg(struct imx8qm_ldb *imx8qm_ldb,
> > > + unsigned long di_clk,
> > > + bool is_split, bool is_slave,
> > > + struct phy_configure_opts_lvds *phy_cfg)
> > > +{
> > > + phy_cfg->bits_per_lane_and_dclk_cycle = 7;
> > > + phy_cfg->lanes = 4;
> > > + phy_cfg->differential_clk_rate = is_split ? di_clk / 2 : di_clk;
> > > + phy_cfg->is_slave = is_slave;
> > > +}
> > > +
> > > +static int imx8qm_ldb_bridge_atomic_check(struct drm_bridge *bridge,
> > > + struct drm_bridge_state *bridge_state,
> > > + struct drm_crtc_state *crtc_state,
> > > + struct drm_connector_state *conn_state)
> > > +{
> > > + struct ldb_channel *ldb_ch = bridge->driver_private;
> > > + struct ldb *ldb = ldb_ch->ldb;
> > > + struct imx8qm_ldb_channel *imx8qm_ldb_ch =
> > > + base_to_imx8qm_ldb_channel(ldb_ch);
> > > + struct imx8qm_ldb *imx8qm_ldb = base_to_imx8qm_ldb(ldb);
> > > + struct drm_display_mode *adj = &crtc_state->adjusted_mode;
> > > + unsigned long di_clk = adj->clock * 1000;
> > > + bool is_split = ldb_channel_is_split_link(ldb_ch);
> > > + union phy_configure_opts opts = { };
> > > + struct phy_configure_opts_lvds *phy_cfg = &opts.lvds;
> > > + int ret;
> > > +
> > > + ret = ldb_bridge_atomic_check_helper(bridge, bridge_state,
> > > + crtc_state, conn_state);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + imx8qm_ldb_set_phy_cfg(imx8qm_ldb, di_clk, is_split, false, phy_cfg);
> > > + ret = phy_validate(imx8qm_ldb_ch->phy, PHY_MODE_LVDS, 0, &opts);
> > > + if (ret < 0) {
> > > + DRM_DEV_DEBUG_DRIVER(imx8qm_ldb->dev,
> > > + "failed to validate PHY: %d\n", ret);
> > > + return ret;
> > > + }
> > > +
> > > + if (is_split) {
> > > + imx8qm_ldb_ch =
> > > + &imx8qm_ldb->channel[imx8qm_ldb->active_chno ^ 1];
> > > + imx8qm_ldb_set_phy_cfg(imx8qm_ldb, di_clk, is_split, true,
> > > + phy_cfg);
> > > + ret = phy_validate(imx8qm_ldb_ch->phy, PHY_MODE_LVDS, 0, &opts);
> > > + if (ret < 0) {
> > > + DRM_DEV_DEBUG_DRIVER(imx8qm_ldb->dev,
> > > + "failed to validate slave PHY: %d\n", ret);
> > > + return ret;
> > > + }
> > > + }
> > > +
> > > + return ret;
> > > +}
> > > +
> > > +static void
> > > +imx8qm_ldb_bridge_mode_set(struct drm_bridge *bridge,
> > > + const struct drm_display_mode *mode,
> > > + const struct drm_display_mode *adjusted_mode)
> > > +{
> > > + struct ldb_channel *ldb_ch = bridge->driver_private;
> > > + struct ldb *ldb = ldb_ch->ldb;
> > > + struct imx8qm_ldb_channel *imx8qm_ldb_ch =
> > > + base_to_imx8qm_ldb_channel(ldb_ch);
> > > + struct imx8qm_ldb *imx8qm_ldb = base_to_imx8qm_ldb(ldb);
> > > + struct device *dev = imx8qm_ldb->dev;
> > > + unsigned long di_clk = adjusted_mode->clock * 1000;
> > > + bool is_split = ldb_channel_is_split_link(ldb_ch);
> > > + union phy_configure_opts opts = { };
> > > + struct phy_configure_opts_lvds *phy_cfg = &opts.lvds;
> > > + u32 chno = ldb_ch->chno;
> > > + int ret;
> > > +
> > > + ret = pm_runtime_get_sync(dev);
> > > + if (ret < 0)
> > > + DRM_DEV_ERROR(dev, "failed to get runtime PM sync: %d\n", ret);
> > > +
> > > + ret = phy_init(imx8qm_ldb_ch->phy);
> > > + if (ret < 0)
> > > + DRM_DEV_ERROR(dev, "failed to initialize PHY: %d\n", ret);
> > > +
> > > + clk_set_rate(imx8qm_ldb->clk_bypass, di_clk);
> > > + clk_set_rate(imx8qm_ldb->clk_pixel, di_clk);
> > > +
> > > + imx8qm_ldb_set_phy_cfg(imx8qm_ldb, di_clk, is_split, false, phy_cfg);
> > > + ret = phy_configure(imx8qm_ldb_ch->phy, &opts);
> > > + if (ret < 0)
> > > + DRM_DEV_ERROR(dev, "failed to configure PHY: %d\n", ret);
> > > +
> > > + if (is_split) {
> > > + imx8qm_ldb_ch =
> > > + &imx8qm_ldb->channel[imx8qm_ldb->active_chno ^ 1];
> > > + imx8qm_ldb_set_phy_cfg(imx8qm_ldb, di_clk, is_split, true,
> > > + phy_cfg);
> > > + ret = phy_configure(imx8qm_ldb_ch->phy, &opts);
> > > + if (ret < 0)
> > > + DRM_DEV_ERROR(dev, "failed to configure slave PHY: %d\n",
> > > + ret);
> > > + }
> > > +
> > > + /* input VSYNC signal from pixel link is active low */
> > > + if (ldb_ch->chno == 0 || is_split)
> > > + ldb->ldb_ctrl |= LDB_DI0_VS_POL_ACT_LOW;
> > > + if (ldb_ch->chno == 1 || is_split)
> > > + ldb->ldb_ctrl |= LDB_DI1_VS_POL_ACT_LOW;
> > > +
> > > + switch (ldb_ch->out_bus_format) {
> > > + case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
> > > + break;
> > > + case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
> > > + case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
> > > + if (ldb_ch->chno == 0 || is_split)
> > > + ldb->ldb_ctrl |= LDB_CH0_DATA_WIDTH_24BIT;
> > > + if (ldb_ch->chno == 1 || is_split)
> > > + ldb->ldb_ctrl |= LDB_CH1_DATA_WIDTH_24BIT;
> > > + break;
> > > + }
> > > +
> > > + ldb_bridge_mode_set_helper(bridge, mode, adjusted_mode);
> > > +
> > > + if (adjusted_mode->flags & DRM_MODE_FLAG_NVSYNC)
> > > + regmap_update_bits(ldb->regmap, SS_CTRL, CH_VSYNC_M(chno), 0);
> > > + else if (adjusted_mode->flags & DRM_MODE_FLAG_PVSYNC)
> > > + regmap_update_bits(ldb->regmap, SS_CTRL,
> > > + CH_VSYNC_M(chno), CH_PVSYNC(chno));
> > > +
> > > + if (adjusted_mode->flags & DRM_MODE_FLAG_NHSYNC)
> > > + regmap_update_bits(ldb->regmap, SS_CTRL, CH_HSYNC_M(chno), 0);
> > > + else if (adjusted_mode->flags & DRM_MODE_FLAG_PHSYNC)
> > > + regmap_update_bits(ldb->regmap, SS_CTRL,
> > > + CH_HSYNC_M(chno), CH_PHSYNC(chno));
> > > +}
> > > +
> > > +static void
> > > +imx8qm_ldb_bridge_atomic_enable(struct drm_bridge *bridge,
> > > + struct drm_bridge_state *old_bridge_state)
> > > +{
> > > + struct ldb_channel *ldb_ch = bridge->driver_private;
> > > + struct ldb *ldb = ldb_ch->ldb;
> > > + struct imx8qm_ldb_channel *imx8qm_ldb_ch =
> > > + base_to_imx8qm_ldb_channel(ldb_ch);
> > > + struct imx8qm_ldb *imx8qm_ldb = base_to_imx8qm_ldb(ldb);
> > > + struct device *dev = imx8qm_ldb->dev;
> > > + bool is_split = ldb_channel_is_split_link(ldb_ch);
> > > + int ret;
> > > +
> > > + clk_prepare_enable(imx8qm_ldb->clk_pixel);
> > > + clk_prepare_enable(imx8qm_ldb->clk_bypass);
> > > +
> > > + /* both DI0 and DI1 connect with pixel link, so ok to use DI0 only */
> > > + if (ldb_ch->chno == 0 || is_split) {
> > > + ldb->ldb_ctrl &= ~LDB_CH0_MODE_EN_MASK;
> > > + ldb->ldb_ctrl |= LDB_CH0_MODE_EN_TO_DI0;
> > > + }
> > > + if (ldb_ch->chno == 1 || is_split) {
> > > + ldb->ldb_ctrl &= ~LDB_CH1_MODE_EN_MASK;
> > > + ldb->ldb_ctrl |= LDB_CH1_MODE_EN_TO_DI0;
> > > + }
> > > +
> > > + if (is_split) {
> > > + ret = phy_power_on(imx8qm_ldb->channel[0].phy);
> > > + if (ret)
> > > + DRM_DEV_ERROR(dev,
> > > + "failed to power on channel0 PHY: %d\n",
> > > + ret);
> > > +
> > > + ret = phy_power_on(imx8qm_ldb->channel[1].phy);
> > > + if (ret)
> > > + DRM_DEV_ERROR(dev,
> > > + "failed to power on channel1 PHY: %d\n",
> > > + ret);
> > > + } else {
> > > + ret = phy_power_on(imx8qm_ldb_ch->phy);
> > > + if (ret)
> > > + DRM_DEV_ERROR(dev, "failed to power on PHY: %d\n", ret);
> > > + }
> > > +
> > > + ldb_bridge_enable_helper(bridge);
> > > +}
> > > +
> > > +static void
> > > +imx8qm_ldb_bridge_atomic_disable(struct drm_bridge *bridge,
> > > + struct drm_bridge_state *old_bridge_state)
> > > +{
> > > + struct ldb_channel *ldb_ch = bridge->driver_private;
> > > + struct ldb *ldb = ldb_ch->ldb;
> > > + struct imx8qm_ldb_channel *imx8qm_ldb_ch =
> > > + base_to_imx8qm_ldb_channel(ldb_ch);
> > > + struct imx8qm_ldb *imx8qm_ldb = base_to_imx8qm_ldb(ldb);
> > > + struct device *dev = imx8qm_ldb->dev;
> > > + bool is_split = ldb_channel_is_split_link(ldb_ch);
> > > + int ret;
> > > +
> > > + ldb_bridge_disable_helper(bridge);
> > > +
> > > + if (is_split) {
> > > + ret = phy_power_off(imx8qm_ldb->channel[0].phy);
> > > + if (ret)
> > > + DRM_DEV_ERROR(dev,
> > > + "failed to power off channel0 PHY: %d\n",
> > > + ret);
> > > + ret = phy_power_off(imx8qm_ldb->channel[1].phy);
> > > + if (ret)
> > > + DRM_DEV_ERROR(dev,
> > > + "failed to power off channel1 PHY: %d\n",
> > > + ret);
> > > + } else {
> > > + ret = phy_power_off(imx8qm_ldb_ch->phy);
> > > + if (ret)
> > > + DRM_DEV_ERROR(dev, "failed to power off PHY: %d\n", ret);
> > > + }
> > > +
> > > + clk_disable_unprepare(imx8qm_ldb->clk_bypass);
> > > + clk_disable_unprepare(imx8qm_ldb->clk_pixel);
> > > +
> > > + ret = pm_runtime_put(dev);
> > > + if (ret < 0)
> > > + DRM_DEV_ERROR(dev, "failed to put runtime PM: %d\n", ret);
> > > +}
> > > +
> > > +static const u32 imx8qm_ldb_bus_output_fmts[] = {
> > > + MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,
> > > + MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,
> > > + MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA,
> > > + MEDIA_BUS_FMT_FIXED,
> > > +};
> > > +
> > > +static bool imx8qm_ldb_bus_output_fmt_supported(u32 fmt)
> > > +{
> > > + int i;
> > > +
> > > + for (i = 0; i < ARRAY_SIZE(imx8qm_ldb_bus_output_fmts); i++) {
> > > + if (imx8qm_ldb_bus_output_fmts[i] == fmt)
> > > + return true;
> > > + }
> > > +
> > > + return false;
> > > +}
> > > +
> > > +static u32 *
> > > +imx8qm_ldb_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
> > > + struct drm_bridge_state *bridge_state,
> > > + struct drm_crtc_state *crtc_state,
> > > + struct drm_connector_state *conn_state,
> > > + u32 output_fmt,
> > > + unsigned int *num_input_fmts)
> > > +{
> > > + struct drm_display_info *di;
> > > + const struct drm_format_info *finfo;
> > > + u32 *input_fmts;
> > > +
> > > + if (!imx8qm_ldb_bus_output_fmt_supported(output_fmt))
> > > + return NULL;
> > > +
> > > + *num_input_fmts = 1;
> > > +
> > > + input_fmts = kmalloc(sizeof(*input_fmts), GFP_KERNEL);
> > > + if (!input_fmts)
> > > + return NULL;
> > > +
> > > + switch (output_fmt) {
> > > + case MEDIA_BUS_FMT_FIXED:
> > > + di = &conn_state->connector->display_info;
> > > +
> > > + /*
> > > + * Look at the first bus format to determine input format.
> > > + * Default to MEDIA_BUS_FMT_RGB888_1X36_CPADLO, if no match.
> > > + */
> > > + if (di->num_bus_formats) {
> > > + finfo = drm_format_info(di->bus_formats[0]);
> > > +
> > > + input_fmts[0] = finfo->depth == 18 ?
> > > + MEDIA_BUS_FMT_RGB666_1X36_CPADLO :
> > > + MEDIA_BUS_FMT_RGB888_1X36_CPADLO;
> > > + } else {
> > > + input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X36_CPADLO;
> > > + }
> > > + break;
> > > + case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
> > > + input_fmts[0] = MEDIA_BUS_FMT_RGB666_1X36_CPADLO;
> > > + break;
> > > + case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
> > > + case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
> > > + input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X36_CPADLO;
> > > + break;
> > > + default:
> > > + kfree(input_fmts);
> > > + input_fmts = NULL;
> > > + break;
> > > + }
> > > +
> > > + return input_fmts;
> > > +}
> > > +
> > > +static u32 *
> > > +imx8qm_ldb_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
> > > + struct drm_bridge_state *bridge_state,
> > > + struct drm_crtc_state *crtc_state,
> > > + struct drm_connector_state *conn_state,
> > > + unsigned int *num_output_fmts)
> > > +{
> > > + *num_output_fmts = ARRAY_SIZE(imx8qm_ldb_bus_output_fmts);
> > > + return kmemdup(imx8qm_ldb_bus_output_fmts,
> > > + sizeof(imx8qm_ldb_bus_output_fmts), GFP_KERNEL);
> > > +}
> > > +
> > > +static enum drm_mode_status
> > > +imx8qm_ldb_bridge_mode_valid(struct drm_bridge *bridge,
> > > + const struct drm_display_info *info,
> > > + const struct drm_display_mode *mode)
> > > +{
> > > + struct ldb_channel *ldb_ch = bridge->driver_private;
> > > + bool is_single = ldb_channel_is_single_link(ldb_ch);
> > > +
> > > + if (mode->clock > 300000)
> > > + return MODE_CLOCK_HIGH;
> > > +
> > > + if (mode->clock > 150000 && is_single)
> > > + return MODE_CLOCK_HIGH;
> > > +
> > > + return MODE_OK;
> > > +}
> > > +
> > > +static const struct drm_bridge_funcs imx8qm_ldb_bridge_funcs = {
> > > + .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
> > > + .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
> > > + .atomic_reset = drm_atomic_helper_bridge_reset,
> > > + .mode_valid = imx8qm_ldb_bridge_mode_valid,
> > > + .attach = ldb_bridge_attach_helper,
> > > + .atomic_check = imx8qm_ldb_bridge_atomic_check,
> > > + .mode_set = imx8qm_ldb_bridge_mode_set,
> > > + .atomic_enable = imx8qm_ldb_bridge_atomic_enable,
> > > + .atomic_disable = imx8qm_ldb_bridge_atomic_disable,
> > > + .atomic_get_input_bus_fmts =
> > > + imx8qm_ldb_bridge_atomic_get_input_bus_fmts,
> > > + .atomic_get_output_bus_fmts =
> > > + imx8qm_ldb_bridge_atomic_get_output_bus_fmts,
> > > +};
> > > +
> > > +static int imx8qm_ldb_get_phy(struct imx8qm_ldb *imx8qm_ldb)
> > > +{
> > > + struct imx8qm_ldb_channel *imx8qm_ldb_ch;
> > > + struct ldb_channel *ldb_ch;
> > > + struct device *dev = imx8qm_ldb->dev;
> > > + int i, ret;
> > > +
> > > + for (i = 0; i < MAX_LDB_CHAN_NUM; i++) {
> > > + imx8qm_ldb_ch = &imx8qm_ldb->channel[i];
> > > + ldb_ch = &imx8qm_ldb_ch->base;
> > > +
> > > + if (!ldb_ch->is_available)
> > > + continue;
> > > +
> > > + imx8qm_ldb_ch->phy = devm_of_phy_get(dev, ldb_ch->np,
> > > + "lvds_phy");
> > > + if (IS_ERR(imx8qm_ldb_ch->phy)) {
> > > + ret = PTR_ERR(imx8qm_ldb_ch->phy);
> > > + if (ret != -EPROBE_DEFER)
> > > + DRM_DEV_ERROR(dev,
> > > + "failed to get channel%d PHY: %d\n",
> > > + i, ret);
> > > + return ret;
> > > + }
> > > + }
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int imx8qm_ldb_probe(struct platform_device *pdev)
> > > +{
> > > + struct device *dev = &pdev->dev;
> > > + struct imx8qm_ldb *imx8qm_ldb;
> > > + struct imx8qm_ldb_channel *imx8qm_ldb_ch;
> > > + struct ldb *ldb;
> > > + struct ldb_channel *ldb_ch;
> > > + struct device_node *port1, *port2;
> > > + int pixel_order;
> > > + int ret, i;
> > > +
> > > + imx8qm_ldb = devm_kzalloc(dev, sizeof(*imx8qm_ldb), GFP_KERNEL);
> > > + if (!imx8qm_ldb)
> > > + return -ENOMEM;
> > > +
> > > + imx8qm_ldb->clk_pixel = devm_clk_get(dev, "pixel");
> > > + if (IS_ERR(imx8qm_ldb->clk_pixel)) {
> > > + ret = PTR_ERR(imx8qm_ldb->clk_pixel);
> > > + if (ret != -EPROBE_DEFER)
> > > + DRM_DEV_ERROR(dev,
> > > + "failed to get pixel clock: %d\n", ret);
> > > + return ret;
> > > + }
> > > +
> > > + imx8qm_ldb->clk_bypass = devm_clk_get(dev, "bypass");
> > > + if (IS_ERR(imx8qm_ldb->clk_bypass)) {
> > > + ret = PTR_ERR(imx8qm_ldb->clk_bypass);
> > > + if (ret != -EPROBE_DEFER)
> > > + DRM_DEV_ERROR(dev,
> > > + "failed to get bypass clock: %d\n", ret);
> > > + return ret;
> > > + }
> > > +
> > > + imx8qm_ldb->dev = dev;
> > > +
> > > + ldb = &imx8qm_ldb->base;
> > > + ldb->dev = dev;
> > > + ldb->ctrl_reg = 0xe0;
> > > +
> > > + for (i = 0; i < MAX_LDB_CHAN_NUM; i++)
> > > + ldb->channel[i] = &imx8qm_ldb->channel[i].base;
> > > +
> > > + ret = ldb_init_helper(ldb);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + if (ldb->available_ch_cnt == 0) {
> > > + DRM_DEV_DEBUG_DRIVER(dev, "no available channel\n");
> > > + return 0;
> > > + }
> > > +
> > > + if (ldb->available_ch_cnt == 2) {
> > > + port1 = of_graph_get_port_by_id(ldb->channel[0]->np, 1);
> > > + port2 = of_graph_get_port_by_id(ldb->channel[1]->np, 1);
> > > + pixel_order =
> > > + drm_of_lvds_get_dual_link_pixel_order(port1, port2);
> > > + of_node_put(port1);
> > > + of_node_put(port2);
> > > +
> > > + if (pixel_order != DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS) {
> > > + DRM_DEV_ERROR(dev, "invalid dual link pixel order: %d\n",
> > > + pixel_order);
> > > + return -EINVAL;
> > > + }
> > > +
> > > + imx8qm_ldb->active_chno = 0;
> > > + imx8qm_ldb_ch = &imx8qm_ldb->channel[0];
> > > + ldb_ch = &imx8qm_ldb_ch->base;
> > > + ldb_ch->link_type = pixel_order;
> > > + } else {
> > > + for (i = 0; i < MAX_LDB_CHAN_NUM; i++) {
> > > + imx8qm_ldb_ch = &imx8qm_ldb->channel[i];
> > > + ldb_ch = &imx8qm_ldb_ch->base;
> > > +
> > > + if (ldb_ch->is_available) {
> > > + imx8qm_ldb->active_chno = ldb_ch->chno;
> > > + break;
> > > + }
> > > + }
> > > + }
> > > +
> > > + ret = imx8qm_ldb_get_phy(imx8qm_ldb);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + ret = ldb_find_next_bridge_helper(ldb);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + platform_set_drvdata(pdev, imx8qm_ldb);
> > > + pm_runtime_enable(dev);
> > > +
> > > + ldb_add_bridge_helper(ldb, &imx8qm_ldb_bridge_funcs);
> > > +
> > > + return ret;
> > > +}
> > > +
> > > +static int imx8qm_ldb_remove(struct platform_device *pdev)
> > > +{
> > > + struct imx8qm_ldb *imx8qm_ldb = platform_get_drvdata(pdev);
> > > + struct ldb *ldb = &imx8qm_ldb->base;
> > > +
> > > + ldb_remove_bridge_helper(ldb);
> > > +
> > > + pm_runtime_disable(&pdev->dev);
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static int __maybe_unused imx8qm_ldb_runtime_suspend(struct device *dev)
> > > +{
> > > + return 0;
> > > +}
> > > +
> > > +static int __maybe_unused imx8qm_ldb_runtime_resume(struct device *dev)
> > > +{
> > > + struct imx8qm_ldb *imx8qm_ldb = dev_get_drvdata(dev);
> > > + struct ldb *ldb = &imx8qm_ldb->base;
> > > +
> > > + /* disable LDB by resetting the control register to POR default */
> > > + regmap_write(ldb->regmap, ldb->ctrl_reg, 0);
> > > +
> > > + return 0;
> > > +}
> > > +
> > > +static const struct dev_pm_ops imx8qm_ldb_pm_ops = {
> > > + SET_RUNTIME_PM_OPS(imx8qm_ldb_runtime_suspend,
> > > + imx8qm_ldb_runtime_resume, NULL)
> > > +};
> > > +
> > > +static const struct of_device_id imx8qm_ldb_dt_ids[] = {
> > > + { .compatible = "fsl,imx8qm-ldb" },
> > > + { /* sentinel */ }
> > > +};
> > > +MODULE_DEVICE_TABLE(of, imx8qm_ldb_dt_ids);
> > > +
> > > +static struct platform_driver imx8qm_ldb_driver = {
> > > + .probe = imx8qm_ldb_probe,
> > > + .remove = imx8qm_ldb_remove,
> > > + .driver = {
> > > + .pm = &imx8qm_ldb_pm_ops,
> > > + .name = DRIVER_NAME,
> > > + .of_match_table = imx8qm_ldb_dt_ids,
> > > + },
> > > +};
> > > +module_platform_driver(imx8qm_ldb_driver);
> > > +
> > > +MODULE_DESCRIPTION("i.MX8QM LVDS Display Bridge(LDB)/Pixel Mapper bridge driver");
> > > +MODULE_AUTHOR("Liu Ying <victor.liu@xxxxxxx>");
> > > +MODULE_LICENSE("GPL v2");
> > > +MODULE_ALIAS("platform:" DRIVER_NAME);
> > > --
> > > 2.7.4
> > >
>