Re: [PATCH v10 2/2] drm/bridge: Add NWL MIPI DSI host controller support
From: Sam Ravnborg
Date: Wed Apr 08 2020 - 13:53:21 EST
Hi Guido.
On Fri, Mar 20, 2020 at 07:49:10PM +0100, Guido Günther wrote:
> This adds initial support for the NWL MIPI DSI Host controller found on
> i.MX8 SoCs.
>
> It adds support for the i.MX8MQ but the same IP can be found on
> e.g. the i.MX8QXP.
>
> It has been tested on the Librem 5 devkit using mxsfb.
>
> Signed-off-by: Guido Günther <agx@xxxxxxxxxxx>
> Co-developed-by: Robert Chiras <robert.chiras@xxxxxxx>
> Signed-off-by: Robert Chiras <robert.chiras@xxxxxxx>
> Tested-by: Robert Chiras <robert.chiras@xxxxxxx>
> Tested-by: Martin Kepplinger <martin.kepplinger@xxxxxxx>
I took an extra look at the driver (procastinating).
checkpatch (--strict):
-:511: CHECK:OPEN_ENDED_LINE: Lines should not end with a '('
#511: FILE: drivers/gpu/drm/bridge/nwl-dsi.c:442:
+ DRM_DEV_ERROR(
-:671: CHECK:COMPARISON_TO_NULL: Comparison to NULL could be written "msg->rx_buf"
#671: FILE: drivers/gpu/drm/bridge/nwl-dsi.c:602:
+ msg->rx_len > 0 && msg->rx_buf != NULL)
-:868: CHECK:OPEN_ENDED_LINE: Lines should not end with a '('
#868: FILE: drivers/gpu/drm/bridge/nwl-dsi.c:799:
+ ret = phy_mipi_dphy_get_default_config(
-:1021: WARNING:RETURN_VOID: void function return statements are not generally useful
#1021: FILE: drivers/gpu/drm/bridge/nwl-dsi.c:952:
+ return;
+}
-:1067: CHECK:LINE_SPACING: Please don't use multiple blank lines
#1067: FILE: drivers/gpu/drm/bridge/nwl-dsi.c:998:
+
+
A few more details below.
Sam
> ---
> drivers/gpu/drm/bridge/Kconfig | 16 +
> drivers/gpu/drm/bridge/Makefile | 1 +
> drivers/gpu/drm/bridge/nwl-dsi.c | 1218 ++++++++++++++++++++++++++++++
> drivers/gpu/drm/bridge/nwl-dsi.h | 144 ++++
> 4 files changed, 1379 insertions(+)
> create mode 100644 drivers/gpu/drm/bridge/nwl-dsi.c
> create mode 100644 drivers/gpu/drm/bridge/nwl-dsi.h
>
> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> index aaed2347ace9..6ec945f837b8 100644
> --- a/drivers/gpu/drm/bridge/Kconfig
> +++ b/drivers/gpu/drm/bridge/Kconfig
> @@ -58,6 +58,22 @@ 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_NWL_MIPI_DSI
> + tristate "Northwest Logic MIPI DSI Host controller"
> + depends on DRM
> + depends on COMMON_CLK
> + depends on OF && HAS_IOMEM
> + select DRM_KMS_HELPER
> + select DRM_MIPI_DSI
> + select DRM_PANEL_BRIDGE
> + select GENERIC_PHY_MIPI_DPHY
> + select MFD_SYSCON
> + select MULTIPLEXER
> + select REGMAP_MMIO
> + help
> + This enables the Northwest Logic MIPI DSI Host controller as
> + for example found on NXP's i.MX8 Processors.
> +
> config DRM_NXP_PTN3460
> tristate "NXP PTN3460 DP/LVDS bridge"
> depends on OF
> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> index 6fb062b5b0f0..b04ac2dfa22c 100644
> --- a/drivers/gpu/drm/bridge/Makefile
> +++ b/drivers/gpu/drm/bridge/Makefile
> @@ -18,6 +18,7 @@ obj-$(CONFIG_DRM_I2C_ADV7511) += adv7511/
> obj-$(CONFIG_DRM_TI_SN65DSI86) += ti-sn65dsi86.o
> obj-$(CONFIG_DRM_TI_TFP410) += ti-tfp410.o
> obj-$(CONFIG_DRM_TI_TPD12S015) += ti-tpd12s015.o
> +obj-$(CONFIG_DRM_NWL_MIPI_DSI) += nwl-dsi.o
>
> obj-y += analogix/
> obj-y += synopsys/
> diff --git a/drivers/gpu/drm/bridge/nwl-dsi.c b/drivers/gpu/drm/bridge/nwl-dsi.c
> new file mode 100644
> index 000000000000..12d1c5548e2d
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/nwl-dsi.c
> @@ -0,0 +1,1218 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * i.MX8 NWL MIPI DSI host driver
> + *
> + * Copyright (C) 2017 NXP
> + * Copyright (C) 2020 Purism SPC
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/clk.h>
> +#include <linux/irq.h>
> +#include <linux/math64.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/mux/consumer.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/phy/phy.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include <linux/sys_soc.h>
> +#include <linux/time64.h>
> +
> +#include <drm/drm_atomic_helper.h>
Header file is not used - drop
> +#include <drm/drm_bridge.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>
Header file is not used - drop
> +
> +#include <video/mipi_display.h>
> +#include <video/videomode.h>
Header file not used
> +
> +#include "nwl-dsi.h"
> +
> +#define DRV_NAME "nwl-dsi"
> +
> +/* i.MX8 NWL quirks */
> +/* i.MX8MQ errata E11418 */
> +#define E11418_HS_MODE_QUIRK BIT(0)
> +
> +#define NWL_DSI_MIPI_FIFO_TIMEOUT msecs_to_jiffies(500)
Should the defines be moved to the header file?
> +
> +enum transfer_direction {
> + DSI_PACKET_SEND,
> + DSI_PACKET_RECEIVE,
> +};
> +
> +#define NWL_DSI_ENDPOINT_LCDIF 0
> +#define NWL_DSI_ENDPOINT_DCSS 1
> +
> +struct nwl_dsi_plat_clk_config {
> + const char *id;
> + struct clk *clk;
> + bool present;
> +};
> +
> +struct nwl_dsi_transfer {
> + const struct mipi_dsi_msg *msg;
> + struct mipi_dsi_packet packet;
> + struct completion completed;
> +
> + int status; /* status of transmission */
> + enum transfer_direction direction;
> + bool need_bta;
> + u8 cmd;
> + u16 rx_word_count;
> + size_t tx_len; /* in bytes */
> + size_t rx_len; /* in bytes */
> +};
> +
> +struct nwl_dsi {
> + struct drm_bridge bridge;
> + struct mipi_dsi_host dsi_host;
> + struct drm_bridge *panel_bridge;
> + struct device *dev;
> + struct phy *phy;
> + union phy_configure_opts phy_cfg;
> + unsigned int quirks;
> +
> + struct regmap *regmap;
> + int irq;
> + /*
> + * The DSI host controller needs this reset sequence according to NWL:
> + * 1. Deassert pclk reset to get access to DSI regs
> + * 2. Configure DSI Host and DPHY and enable DPHY
> + * 3. Deassert ESC and BYTE resets to allow host TX operations)
> + * 4. Send DSI cmds to configure peripheral (handled by panel drv)
> + * 5. Deassert DPI reset so DPI receives pixels and starts sending
> + * DSI data
> + *
> + * TODO: Since panel_bridges do their DSI setup in enable we
> + * currently have 4. and 5. swapped.
> + */
> + struct reset_control *rst_byte;
> + struct reset_control *rst_esc;
> + struct reset_control *rst_dpi;
> + struct reset_control *rst_pclk;
> + struct mux_control *mux;
> +
> + /* DSI clocks */
> + struct clk *phy_ref_clk;
> + struct clk *rx_esc_clk;
> + struct clk *tx_esc_clk;
> + struct clk *core_clk;
> + /*
> + * hardware bug: the i.MX8MQ needs this clock on during reset
> + * even when not using LCDIF.
> + */
> + struct clk *lcdif_clk;
> +
> + /* dsi lanes */
> + u32 lanes;
> + enum mipi_dsi_pixel_format format;
> + struct drm_display_mode mode;
> + unsigned long dsi_mode_flags;
> + int error;
> +
> + struct nwl_dsi_transfer *xfer;
> +};
> +
> +static const struct regmap_config nwl_dsi_regmap_config = {
> + .reg_bits = 16,
> + .val_bits = 32,
> + .reg_stride = 4,
> + .max_register = NWL_DSI_IRQ_MASK2,
> + .name = DRV_NAME,
> +};
> +
> +static inline struct nwl_dsi *bridge_to_dsi(struct drm_bridge *bridge)
> +{
> + return container_of(bridge, struct nwl_dsi, bridge);
> +}
> +
> +static int nwl_dsi_clear_error(struct nwl_dsi *dsi)
> +{
> + int ret = dsi->error;
> +
> + dsi->error = 0;
> + return ret;
> +}
> +
> +static void nwl_dsi_write(struct nwl_dsi *dsi, unsigned int reg, u32 val)
> +{
> + int ret;
> +
> + if (dsi->error)
> + return;
> +
> + ret = regmap_write(dsi->regmap, reg, val);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dsi->dev,
> + "Failed to write NWL DSI reg 0x%x: %d\n", reg,
> + ret);
> + dsi->error = ret;
> + }
> +}
> +
> +static u32 nwl_dsi_read(struct nwl_dsi *dsi, u32 reg)
> +{
> + unsigned int val;
> + int ret;
> +
> + if (dsi->error)
> + return 0;
> +
> + ret = regmap_read(dsi->regmap, reg, &val);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to read NWL DSI reg 0x%x: %d\n",
> + reg, ret);
> + dsi->error = ret;
> + }
> + return val;
> +}
> +
> +static int nwl_dsi_get_dpi_pixel_format(enum mipi_dsi_pixel_format format)
> +{
> + switch (format) {
> + case MIPI_DSI_FMT_RGB565:
> + return NWL_DSI_PIXEL_FORMAT_16;
> + case MIPI_DSI_FMT_RGB666:
> + return NWL_DSI_PIXEL_FORMAT_18L;
> + case MIPI_DSI_FMT_RGB666_PACKED:
> + return NWL_DSI_PIXEL_FORMAT_18;
> + case MIPI_DSI_FMT_RGB888:
> + return NWL_DSI_PIXEL_FORMAT_24;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +/*
> + * ps2bc - Picoseconds to byte clock cycles
> + */
> +static u32 ps2bc(struct nwl_dsi *dsi, unsigned long long ps)
> +{
> + u32 bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> +
> + return DIV64_U64_ROUND_UP(ps * dsi->mode.clock * bpp,
> + dsi->lanes * 8 * NSEC_PER_SEC);
> +}
> +
> +/*
> + * ui2bc - UI time periods to byte clock cycles
> + */
> +static u32 ui2bc(struct nwl_dsi *dsi, unsigned long long ui)
> +{
> + u32 bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> +
> + return DIV64_U64_ROUND_UP(ui * dsi->lanes,
> + dsi->mode.clock * 1000 * bpp);
> +}
> +
> +/*
> + * us2bc - micro seconds to lp clock cycles
> + */
> +static u32 us2lp(u32 lp_clk_rate, unsigned long us)
> +{
> + return DIV_ROUND_UP(us * lp_clk_rate, USEC_PER_SEC);
> +}
> +
> +static int nwl_dsi_config_host(struct nwl_dsi *dsi)
> +{
> + u32 cycles;
> + struct phy_configure_opts_mipi_dphy *cfg = &dsi->phy_cfg.mipi_dphy;
> +
> + if (dsi->lanes < 1 || dsi->lanes > 4)
> + return -EINVAL;
> +
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "DSI Lanes %d\n", dsi->lanes);
> + nwl_dsi_write(dsi, NWL_DSI_CFG_NUM_LANES, dsi->lanes - 1);
> +
> + if (dsi->dsi_mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) {
> + nwl_dsi_write(dsi, NWL_DSI_CFG_NONCONTINUOUS_CLK, 0x01);
> + nwl_dsi_write(dsi, NWL_DSI_CFG_AUTOINSERT_EOTP, 0x01);
> + } else {
> + nwl_dsi_write(dsi, NWL_DSI_CFG_NONCONTINUOUS_CLK, 0x00);
> + nwl_dsi_write(dsi, NWL_DSI_CFG_AUTOINSERT_EOTP, 0x00);
> + }
> +
> + /* values in byte clock cycles */
> + cycles = ui2bc(dsi, cfg->clk_pre);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_t_pre: 0x%x\n", cycles);
> + nwl_dsi_write(dsi, NWL_DSI_CFG_T_PRE, cycles);
> + cycles = ps2bc(dsi, cfg->lpx + cfg->clk_prepare + cfg->clk_zero);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_tx_gap (pre): 0x%x\n", cycles);
> + cycles += ui2bc(dsi, cfg->clk_pre);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_t_post: 0x%x\n", cycles);
> + nwl_dsi_write(dsi, NWL_DSI_CFG_T_POST, cycles);
> + cycles = ps2bc(dsi, cfg->hs_exit);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_tx_gap: 0x%x\n", cycles);
> + nwl_dsi_write(dsi, NWL_DSI_CFG_TX_GAP, cycles);
> +
> + nwl_dsi_write(dsi, NWL_DSI_CFG_EXTRA_CMDS_AFTER_EOTP, 0x01);
> + nwl_dsi_write(dsi, NWL_DSI_CFG_HTX_TO_COUNT, 0x00);
> + nwl_dsi_write(dsi, NWL_DSI_CFG_LRX_H_TO_COUNT, 0x00);
> + nwl_dsi_write(dsi, NWL_DSI_CFG_BTA_H_TO_COUNT, 0x00);
> + /* In LP clock cycles */
> + cycles = us2lp(cfg->lp_clk_rate, cfg->wakeup);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_twakeup: 0x%x\n", cycles);
> + nwl_dsi_write(dsi, NWL_DSI_CFG_TWAKEUP, cycles);
> +
> + return nwl_dsi_clear_error(dsi);
> +}
> +
> +static int nwl_dsi_config_dpi(struct nwl_dsi *dsi)
> +{
> + u32 mode;
> + int color_format;
> + bool burst_mode;
> + int hfront_porch, hback_porch, vfront_porch, vback_porch;
> + int hsync_len, vsync_len;
> +
> + hfront_porch = dsi->mode.hsync_start - dsi->mode.hdisplay;
> + hsync_len = dsi->mode.hsync_end - dsi->mode.hsync_start;
> + hback_porch = dsi->mode.htotal - dsi->mode.hsync_end;
> +
> + vfront_porch = dsi->mode.vsync_start - dsi->mode.vdisplay;
> + vsync_len = dsi->mode.vsync_end - dsi->mode.vsync_start;
> + vback_porch = dsi->mode.vtotal - dsi->mode.vsync_end;
> +
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "hfront_porch = %d\n", hfront_porch);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "hback_porch = %d\n", hback_porch);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "hsync_len = %d\n", hsync_len);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "hdisplay = %d\n", dsi->mode.hdisplay);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "vfront_porch = %d\n", vfront_porch);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "vback_porch = %d\n", vback_porch);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "vsync_len = %d\n", vsync_len);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "vactive = %d\n", dsi->mode.vdisplay);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "clock = %d kHz\n", dsi->mode.clock);
> +
> + color_format = nwl_dsi_get_dpi_pixel_format(dsi->format);
> + if (color_format < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Invalid color format 0x%x\n",
> + dsi->format);
> + return color_format;
> + }
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "pixel fmt = %d\n", dsi->format);
> +
> + nwl_dsi_write(dsi, NWL_DSI_INTERFACE_COLOR_CODING, NWL_DSI_DPI_24_BIT);
> + nwl_dsi_write(dsi, NWL_DSI_PIXEL_FORMAT, color_format);
> + /*
> + * Adjusting input polarity based on the video mode results in
> + * a black screen so always pick active low:
> + */
> + nwl_dsi_write(dsi, NWL_DSI_VSYNC_POLARITY,
> + NWL_DSI_VSYNC_POLARITY_ACTIVE_LOW);
> + nwl_dsi_write(dsi, NWL_DSI_HSYNC_POLARITY,
> + NWL_DSI_HSYNC_POLARITY_ACTIVE_LOW);
> +
> + burst_mode = (dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_BURST) &&
> + !(dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE);
> +
> + if (burst_mode) {
> + nwl_dsi_write(dsi, NWL_DSI_VIDEO_MODE, NWL_DSI_VM_BURST_MODE);
> + nwl_dsi_write(dsi, NWL_DSI_PIXEL_FIFO_SEND_LEVEL, 256);
> + } else {
> + mode = ((dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) ?
> + NWL_DSI_VM_BURST_MODE_WITH_SYNC_PULSES :
> + NWL_DSI_VM_NON_BURST_MODE_WITH_SYNC_EVENTS);
> + nwl_dsi_write(dsi, NWL_DSI_VIDEO_MODE, mode);
> + nwl_dsi_write(dsi, NWL_DSI_PIXEL_FIFO_SEND_LEVEL,
> + dsi->mode.hdisplay);
> + }
> +
> + nwl_dsi_write(dsi, NWL_DSI_HFP, hfront_porch);
> + nwl_dsi_write(dsi, NWL_DSI_HBP, hback_porch);
> + nwl_dsi_write(dsi, NWL_DSI_HSA, hsync_len);
> +
> + nwl_dsi_write(dsi, NWL_DSI_ENABLE_MULT_PKTS, 0x0);
> + nwl_dsi_write(dsi, NWL_DSI_BLLP_MODE, 0x1);
> + nwl_dsi_write(dsi, NWL_DSI_USE_NULL_PKT_BLLP, 0x0);
> + nwl_dsi_write(dsi, NWL_DSI_VC, 0x0);
> +
> + nwl_dsi_write(dsi, NWL_DSI_PIXEL_PAYLOAD_SIZE, dsi->mode.hdisplay);
> + nwl_dsi_write(dsi, NWL_DSI_VACTIVE, dsi->mode.vdisplay - 1);
> + nwl_dsi_write(dsi, NWL_DSI_VBP, vback_porch);
> + nwl_dsi_write(dsi, NWL_DSI_VFP, vfront_porch);
> +
> + return nwl_dsi_clear_error(dsi);
> +}
> +
> +static int nwl_dsi_init_interrupts(struct nwl_dsi *dsi)
> +{
> + u32 irq_enable;
> +
> + nwl_dsi_write(dsi, NWL_DSI_IRQ_MASK, 0xffffffff);
> + nwl_dsi_write(dsi, NWL_DSI_IRQ_MASK2, 0x7);
> +
> + irq_enable = ~(u32)(NWL_DSI_TX_PKT_DONE_MASK |
> + NWL_DSI_RX_PKT_HDR_RCVD_MASK |
> + NWL_DSI_TX_FIFO_OVFLW_MASK |
> + NWL_DSI_HS_TX_TIMEOUT_MASK);
> +
> + nwl_dsi_write(dsi, NWL_DSI_IRQ_MASK, irq_enable);
> +
> + return nwl_dsi_clear_error(dsi);
> +}
> +
> +static int nwl_dsi_host_attach(struct mipi_dsi_host *dsi_host,
> + struct mipi_dsi_device *device)
> +{
> + struct nwl_dsi *dsi = container_of(dsi_host, struct nwl_dsi, dsi_host);
> + struct device *dev = dsi->dev;
> +
> + DRM_DEV_INFO(dev, "lanes=%u, format=0x%x flags=0x%lx\n", device->lanes,
> + device->format, device->mode_flags);
> +
> + if (device->lanes < 1 || device->lanes > 4)
> + return -EINVAL;
> +
> + dsi->lanes = device->lanes;
> + dsi->format = device->format;
> + dsi->dsi_mode_flags = device->mode_flags;
> +
> + return 0;
> +}
> +
> +static bool nwl_dsi_read_packet(struct nwl_dsi *dsi, u32 status)
> +{
> + struct device *dev = dsi->dev;
> + struct nwl_dsi_transfer *xfer = dsi->xfer;
> + int err;
> + u8 *payload = xfer->msg->rx_buf;
> + u32 val;
> + u16 word_count;
> + u8 channel;
> + u8 data_type;
> +
> + xfer->status = 0;
> +
> + if (xfer->rx_word_count == 0) {
> + if (!(status & NWL_DSI_RX_PKT_HDR_RCVD))
> + return false;
> + /* Get the RX header and parse it */
> + val = nwl_dsi_read(dsi, NWL_DSI_RX_PKT_HEADER);
> + err = nwl_dsi_clear_error(dsi);
> + if (err)
> + xfer->status = err;
> + word_count = NWL_DSI_WC(val);
> + channel = NWL_DSI_RX_VC(val);
> + data_type = NWL_DSI_RX_DT(val);
> +
> + if (channel != xfer->msg->channel) {
> + DRM_DEV_ERROR(dev,
> + "[%02X] Channel mismatch (%u != %u)\n",
> + xfer->cmd, channel, xfer->msg->channel);
> + xfer->status = -EINVAL;
> + return true;
> + }
> +
> + switch (data_type) {
> + case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_2BYTE:
> + fallthrough;
> + case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_2BYTE:
> + if (xfer->msg->rx_len > 1) {
> + /* read second byte */
> + payload[1] = word_count >> 8;
> + ++xfer->rx_len;
> + }
> + fallthrough;
> + case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_1BYTE:
> + fallthrough;
> + case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_1BYTE:
> + if (xfer->msg->rx_len > 0) {
> + /* read first byte */
> + payload[0] = word_count & 0xff;
> + ++xfer->rx_len;
> + }
> + xfer->status = xfer->rx_len;
> + return true;
> + case MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT:
> + word_count &= 0xff;
> + DRM_DEV_ERROR(dev, "[%02X] DSI error report: 0x%02x\n",
> + xfer->cmd, word_count);
> + xfer->status = -EPROTO;
> + return true;
> + }
> +
> + if (word_count > xfer->msg->rx_len) {
> + DRM_DEV_ERROR(
> + dev,
> + "[%02X] Receive buffer too small: %zu (< %u)\n",
> + xfer->cmd, xfer->msg->rx_len, word_count);
> + xfer->status = -EINVAL;
> + return true;
> + }
> +
> + xfer->rx_word_count = word_count;
> + } else {
> + /* Set word_count from previous header read */
> + word_count = xfer->rx_word_count;
> + }
> +
> + /* If RX payload is not yet received, wait for it */
> + if (!(status & NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD))
> + return false;
> +
> + /* Read the RX payload */
> + while (word_count >= 4) {
> + val = nwl_dsi_read(dsi, NWL_DSI_RX_PAYLOAD);
> + payload[0] = (val >> 0) & 0xff;
> + payload[1] = (val >> 8) & 0xff;
> + payload[2] = (val >> 16) & 0xff;
> + payload[3] = (val >> 24) & 0xff;
> + payload += 4;
> + xfer->rx_len += 4;
> + word_count -= 4;
> + }
> +
> + if (word_count > 0) {
> + val = nwl_dsi_read(dsi, NWL_DSI_RX_PAYLOAD);
> + switch (word_count) {
> + case 3:
> + payload[2] = (val >> 16) & 0xff;
> + ++xfer->rx_len;
> + fallthrough;
> + case 2:
> + payload[1] = (val >> 8) & 0xff;
> + ++xfer->rx_len;
> + fallthrough;
> + case 1:
> + payload[0] = (val >> 0) & 0xff;
> + ++xfer->rx_len;
> + break;
> + }
> + }
> +
> + xfer->status = xfer->rx_len;
> + err = nwl_dsi_clear_error(dsi);
> + if (err)
> + xfer->status = err;
> +
> + return true;
> +}
> +
> +static void nwl_dsi_finish_transmission(struct nwl_dsi *dsi, u32 status)
> +{
> + struct nwl_dsi_transfer *xfer = dsi->xfer;
> + bool end_packet = false;
> +
> + if (!xfer)
> + return;
> +
> + if (xfer->direction == DSI_PACKET_SEND &&
> + status & NWL_DSI_TX_PKT_DONE) {
> + xfer->status = xfer->tx_len;
> + end_packet = true;
> + } else if (status & NWL_DSI_DPHY_DIRECTION &&
> + ((status & (NWL_DSI_RX_PKT_HDR_RCVD |
> + NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD)))) {
> + end_packet = nwl_dsi_read_packet(dsi, status);
> + }
> +
> + if (end_packet)
> + complete(&xfer->completed);
> +}
> +
> +static void nwl_dsi_begin_transmission(struct nwl_dsi *dsi)
> +{
> + struct nwl_dsi_transfer *xfer = dsi->xfer;
> + struct mipi_dsi_packet *pkt = &xfer->packet;
> + const u8 *payload;
> + size_t length;
> + u16 word_count;
> + u8 hs_mode;
> + u32 val;
> + u32 hs_workaround = 0;
> +
> + /* Send the payload, if any */
> + length = pkt->payload_length;
> + payload = pkt->payload;
> +
> + while (length >= 4) {
> + val = *(u32 *)payload;
> + hs_workaround |= !(val & 0xFFFF00);
> + nwl_dsi_write(dsi, NWL_DSI_TX_PAYLOAD, val);
> + payload += 4;
> + length -= 4;
> + }
> + /* Send the rest of the payload */
> + val = 0;
> + switch (length) {
> + case 3:
> + val |= payload[2] << 16;
> + fallthrough;
> + case 2:
> + val |= payload[1] << 8;
> + hs_workaround |= !(val & 0xFFFF00);
> + fallthrough;
> + case 1:
> + val |= payload[0];
> + nwl_dsi_write(dsi, NWL_DSI_TX_PAYLOAD, val);
> + break;
> + }
> + xfer->tx_len = pkt->payload_length;
> +
> + /*
> + * Send the header
> + * header[0] = Virtual Channel + Data Type
> + * header[1] = Word Count LSB (LP) or first param (SP)
> + * header[2] = Word Count MSB (LP) or second param (SP)
> + */
> + word_count = pkt->header[1] | (pkt->header[2] << 8);
> + if (hs_workaround && (dsi->quirks & E11418_HS_MODE_QUIRK)) {
> + DRM_DEV_DEBUG_DRIVER(dsi->dev,
> + "Using hs mode workaround for cmd 0x%x\n",
> + xfer->cmd);
> + hs_mode = 1;
> + } else {
> + hs_mode = (xfer->msg->flags & MIPI_DSI_MSG_USE_LPM) ? 0 : 1;
> + }
> + val = NWL_DSI_WC(word_count) | NWL_DSI_TX_VC(xfer->msg->channel) |
> + NWL_DSI_TX_DT(xfer->msg->type) | NWL_DSI_HS_SEL(hs_mode) |
> + NWL_DSI_BTA_TX(xfer->need_bta);
> + nwl_dsi_write(dsi, NWL_DSI_PKT_CONTROL, val);
> +
> + /* Send packet command */
> + nwl_dsi_write(dsi, NWL_DSI_SEND_PACKET, 0x1);
> +}
> +
> +static ssize_t nwl_dsi_host_transfer(struct mipi_dsi_host *dsi_host,
> + const struct mipi_dsi_msg *msg)
> +{
> + struct nwl_dsi *dsi = container_of(dsi_host, struct nwl_dsi, dsi_host);
> + struct nwl_dsi_transfer xfer;
> + ssize_t ret = 0;
> +
> + /* Create packet to be sent */
> + dsi->xfer = &xfer;
> + ret = mipi_dsi_create_packet(&xfer.packet, msg);
> + if (ret < 0) {
> + dsi->xfer = NULL;
> + return ret;
> + }
> +
> + if ((msg->type & MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM ||
> + msg->type & MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM ||
> + msg->type & MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM ||
> + msg->type & MIPI_DSI_DCS_READ) &&
> + msg->rx_len > 0 && msg->rx_buf != NULL)
> + xfer.direction = DSI_PACKET_RECEIVE;
> + else
> + xfer.direction = DSI_PACKET_SEND;
> +
> + xfer.need_bta = (xfer.direction == DSI_PACKET_RECEIVE);
> + xfer.need_bta |= (msg->flags & MIPI_DSI_MSG_REQ_ACK) ? 1 : 0;
> + xfer.msg = msg;
> + xfer.status = -ETIMEDOUT;
> + xfer.rx_word_count = 0;
> + xfer.rx_len = 0;
> + xfer.cmd = 0x00;
> + if (msg->tx_len > 0)
> + xfer.cmd = ((u8 *)(msg->tx_buf))[0];
> + init_completion(&xfer.completed);
> +
> + ret = clk_prepare_enable(dsi->rx_esc_clk);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to enable rx_esc clk: %zd\n",
> + ret);
> + return ret;
> + }
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "Enabled rx_esc clk @%lu Hz\n",
> + clk_get_rate(dsi->rx_esc_clk));
> +
> + /* Initiate the DSI packet transmision */
> + nwl_dsi_begin_transmission(dsi);
> +
> + if (!wait_for_completion_timeout(&xfer.completed,
> + NWL_DSI_MIPI_FIFO_TIMEOUT)) {
> + DRM_DEV_ERROR(dsi_host->dev, "[%02X] DSI transfer timed out\n",
> + xfer.cmd);
> + ret = -ETIMEDOUT;
> + } else {
> + ret = xfer.status;
> + }
> +
> + clk_disable_unprepare(dsi->rx_esc_clk);
> +
> + return ret;
> +}
> +
> +static const struct mipi_dsi_host_ops nwl_dsi_host_ops = {
> + .attach = nwl_dsi_host_attach,
> + .transfer = nwl_dsi_host_transfer,
> +};
> +
> +static irqreturn_t nwl_dsi_irq_handler(int irq, void *data)
> +{
> + u32 irq_status;
> + struct nwl_dsi *dsi = data;
> +
> + irq_status = nwl_dsi_read(dsi, NWL_DSI_IRQ_STATUS);
> +
> + if (irq_status & NWL_DSI_TX_FIFO_OVFLW)
> + DRM_DEV_ERROR_RATELIMITED(dsi->dev, "tx fifo overflow\n");
> +
> + if (irq_status & NWL_DSI_HS_TX_TIMEOUT)
> + DRM_DEV_ERROR_RATELIMITED(dsi->dev, "HS tx timeout\n");
> +
> + if (irq_status & NWL_DSI_TX_PKT_DONE ||
> + irq_status & NWL_DSI_RX_PKT_HDR_RCVD ||
> + irq_status & NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD)
> + nwl_dsi_finish_transmission(dsi, irq_status);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int nwl_dsi_enable(struct nwl_dsi *dsi)
> +{
> + struct device *dev = dsi->dev;
> + union phy_configure_opts *phy_cfg = &dsi->phy_cfg;
> + int ret;
> +
> + if (!dsi->lanes) {
> + DRM_DEV_ERROR(dev, "Need DSI lanes: %d\n", dsi->lanes);
> + return -EINVAL;
> + }
> +
> + ret = phy_init(dsi->phy);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dev, "Failed to init DSI phy: %d\n", ret);
> + return ret;
> + }
> +
> + ret = phy_configure(dsi->phy, phy_cfg);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dev, "Failed to configure DSI phy: %d\n", ret);
> + goto uninit_phy;
> + }
> +
> + ret = clk_prepare_enable(dsi->tx_esc_clk);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to enable tx_esc clk: %d\n",
> + ret);
> + goto uninit_phy;
> + }
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "Enabled tx_esc clk @%lu Hz\n",
> + clk_get_rate(dsi->tx_esc_clk));
> +
> + ret = nwl_dsi_config_host(dsi);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dev, "Failed to set up DSI: %d", ret);
> + goto disable_clock;
> + }
> +
> + ret = nwl_dsi_config_dpi(dsi);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dev, "Failed to set up DPI: %d", ret);
> + goto disable_clock;
> + }
> +
> + ret = phy_power_on(dsi->phy);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dev, "Failed to power on DPHY (%d)\n", ret);
> + goto disable_clock;
> + }
> +
> + ret = nwl_dsi_init_interrupts(dsi);
> + if (ret < 0)
> + goto power_off_phy;
> +
> + return ret;
> +
> +power_off_phy:
> + phy_power_off(dsi->phy);
> +disable_clock:
> + clk_disable_unprepare(dsi->tx_esc_clk);
> +uninit_phy:
> + phy_exit(dsi->phy);
> +
> + return ret;
> +}
> +
> +static int nwl_dsi_disable(struct nwl_dsi *dsi)
> +{
> + struct device *dev = dsi->dev;
> +
> + DRM_DEV_DEBUG_DRIVER(dev, "Disabling clocks and phy\n");
> +
> + phy_power_off(dsi->phy);
> + phy_exit(dsi->phy);
> +
> + /* Disabling the clock before the phy breaks enabling dsi again */
> + clk_disable_unprepare(dsi->tx_esc_clk);
> +
> + return 0;
> +}
> +
> +static void nwl_dsi_bridge_disable(struct drm_bridge *bridge)
> +{
> + struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> + int ret;
> +
> + nwl_dsi_disable(dsi);
> +
> + ret = reset_control_assert(dsi->rst_dpi);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to assert DPI: %d\n", ret);
> + return;
> + }
> + ret = reset_control_assert(dsi->rst_byte);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to assert ESC: %d\n", ret);
> + return;
> + }
> + ret = reset_control_assert(dsi->rst_esc);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to assert BYTE: %d\n", ret);
> + return;
> + }
> + ret = reset_control_assert(dsi->rst_pclk);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to assert PCLK: %d\n", ret);
> + return;
> + }
> +
> + clk_disable_unprepare(dsi->core_clk);
> + clk_disable_unprepare(dsi->lcdif_clk);
> +
> + pm_runtime_put(dsi->dev);
> +}
> +
> +static int nwl_dsi_get_dphy_params(struct nwl_dsi *dsi,
> + const struct drm_display_mode *mode,
> + union phy_configure_opts *phy_opts)
> +{
> + unsigned long rate;
> + int ret;
> +
> + if (dsi->lanes < 1 || dsi->lanes > 4)
> + return -EINVAL;
> +
> + /*
> + * So far the DPHY spec minimal timings work for both mixel
> + * dphy and nwl dsi host
> + */
> + ret = phy_mipi_dphy_get_default_config(
> + mode->clock * 1000,
> + mipi_dsi_pixel_format_to_bpp(dsi->format), dsi->lanes,
> + &phy_opts->mipi_dphy);
> + if (ret < 0)
> + return ret;
> +
> + rate = clk_get_rate(dsi->tx_esc_clk);
> + DRM_DEV_DEBUG_DRIVER(dsi->dev, "LP clk is @%lu Hz\n", rate);
> + phy_opts->mipi_dphy.lp_clk_rate = rate;
> +
> + return 0;
> +}
> +
> +static bool nwl_dsi_bridge_mode_fixup(struct drm_bridge *bridge,
> + const struct drm_display_mode *mode,
> + struct drm_display_mode *adjusted_mode)
> +{
> + /* At least LCDIF + NWL needs active high sync */
> + adjusted_mode->flags |= (DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
> + adjusted_mode->flags &= ~(DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
> +
> + return true;
> +}
> +
> +static enum drm_mode_status
> +nwl_dsi_bridge_mode_valid(struct drm_bridge *bridge,
> + const struct drm_display_mode *mode)
> +{
> + struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> + int bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> +
> + if (mode->clock * bpp > 15000000 * dsi->lanes)
> + return MODE_CLOCK_HIGH;
> +
> + if (mode->clock * bpp < 80000 * dsi->lanes)
> + return MODE_CLOCK_LOW;
> +
> + return MODE_OK;
> +}
> +
> +static void
> +nwl_dsi_bridge_mode_set(struct drm_bridge *bridge,
> + const struct drm_display_mode *mode,
> + const struct drm_display_mode *adjusted_mode)
> +{
> + struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> + struct device *dev = dsi->dev;
> + union phy_configure_opts new_cfg;
> + unsigned long phy_ref_rate;
> + int ret;
> +
> + ret = nwl_dsi_get_dphy_params(dsi, adjusted_mode, &new_cfg);
> + if (ret < 0)
> + return;
> +
> + /*
> + * If hs clock is unchanged, we're all good - all parameters are
> + * derived from it atm.
> + */
> + if (new_cfg.mipi_dphy.hs_clk_rate == dsi->phy_cfg.mipi_dphy.hs_clk_rate)
> + return;
> +
> + phy_ref_rate = clk_get_rate(dsi->phy_ref_clk);
> + DRM_DEV_DEBUG_DRIVER(dev, "PHY at ref rate: %lu\n", phy_ref_rate);
> + /* Save the new desired phy config */
> + memcpy(&dsi->phy_cfg, &new_cfg, sizeof(new_cfg));
> +
> + memcpy(&dsi->mode, adjusted_mode, sizeof(dsi->mode));
> + drm_mode_debug_printmodeline(adjusted_mode);
> +}
> +
> +static void nwl_dsi_bridge_pre_enable(struct drm_bridge *bridge)
> +{
> + struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> + int ret;
> +
> + pm_runtime_get_sync(dsi->dev);
> +
> + if (clk_prepare_enable(dsi->lcdif_clk) < 0)
> + return;
> + if (clk_prepare_enable(dsi->core_clk) < 0)
> + return;
> +
> + /* Step 1 from DSI reset-out instructions */
> + ret = reset_control_deassert(dsi->rst_pclk);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to deassert PCLK: %d\n", ret);
> + return;
> + }
> +
> + /* Step 2 from DSI reset-out instructions */
> + nwl_dsi_enable(dsi);
> +
> + /* Step 3 from DSI reset-out instructions */
> + ret = reset_control_deassert(dsi->rst_esc);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to deassert ESC: %d\n", ret);
> + return;
> + }
> + ret = reset_control_deassert(dsi->rst_byte);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to deassert BYTE: %d\n", ret);
> + return;
> + }
> +}
> +
> +static void nwl_dsi_bridge_enable(struct drm_bridge *bridge)
> +{
> + struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> + int ret;
> +
> + /* Step 5 from DSI reset-out instructions */
> + ret = reset_control_deassert(dsi->rst_dpi);
> + if (ret < 0)
> + DRM_DEV_ERROR(dsi->dev, "Failed to deassert DPI: %d\n", ret);
> +}
> +
> +static int nwl_dsi_bridge_attach(struct drm_bridge *bridge,
> + enum drm_bridge_attach_flags flags)
> +{
> + struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> + struct drm_bridge *panel_bridge;
> + struct drm_panel *panel;
> + int ret;
> +
> + if (flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)
> + return -EINVAL;
Any chance this driver could be fixed to make connection optional?
Also, other drivers are more friednly and print something if the
DRM_BRIDGE_ATTACH_NO_CONNECTOR flag is set.
Sam
> +
> + ret = drm_of_find_panel_or_bridge(dsi->dev->of_node, 1, 0, &panel,
> + &panel_bridge);
> + if (ret)
> + return ret;
> +
> + if (panel) {
> + panel_bridge = drm_panel_bridge_add(panel);
> + if (IS_ERR(panel_bridge))
> + return PTR_ERR(panel_bridge);
> + }
> + dsi->panel_bridge = panel_bridge;
> +
> + if (!dsi->panel_bridge)
> + return -EPROBE_DEFER;
> +
> + return drm_bridge_attach(bridge->encoder, dsi->panel_bridge, bridge,
> + flags);
> +}
> +
> +static void nwl_dsi_bridge_detach(struct drm_bridge *bridge)
> +{ struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> +
> + drm_of_panel_bridge_remove(dsi->dev->of_node, 1, 0);
> + return;
> +}
> +
> +static const struct drm_bridge_funcs nwl_dsi_bridge_funcs = {
> + .pre_enable = nwl_dsi_bridge_pre_enable,
> + .enable = nwl_dsi_bridge_enable,
> + .disable = nwl_dsi_bridge_disable,
> + .mode_fixup = nwl_dsi_bridge_mode_fixup,
> + .mode_set = nwl_dsi_bridge_mode_set,
> + .mode_valid = nwl_dsi_bridge_mode_valid,
> + .attach = nwl_dsi_bridge_attach,
> + .detach = nwl_dsi_bridge_detach,
> +};
> +
> +static int nwl_dsi_parse_dt(struct nwl_dsi *dsi)
> +{
> + struct platform_device *pdev = to_platform_device(dsi->dev);
> + struct clk *clk;
> + void __iomem *base;
> + int ret;
> +
> + dsi->phy = devm_phy_get(dsi->dev, "dphy");
> + if (IS_ERR(dsi->phy)) {
> + ret = PTR_ERR(dsi->phy);
> + if (ret != -EPROBE_DEFER)
> + DRM_DEV_ERROR(dsi->dev, "Could not get PHY: %d\n", ret);
> + return ret;
> + }
> +
> + clk = devm_clk_get(dsi->dev, "lcdif");
> + if (IS_ERR(clk)) {
> + ret = PTR_ERR(clk);
> + DRM_DEV_ERROR(dsi->dev, "Failed to get lcdif clock: %d\n",
> + ret);
> + return ret;
> + }
> + dsi->lcdif_clk = clk;
> +
> + clk = devm_clk_get(dsi->dev, "core");
> + if (IS_ERR(clk)) {
> + ret = PTR_ERR(clk);
> + DRM_DEV_ERROR(dsi->dev, "Failed to get core clock: %d\n",
> + ret);
> + return ret;
> + }
> + dsi->core_clk = clk;
> +
> +
> + clk = devm_clk_get(dsi->dev, "phy_ref");
> + if (IS_ERR(clk)) {
> + ret = PTR_ERR(clk);
> + DRM_DEV_ERROR(dsi->dev, "Failed to get phy_ref clock: %d\n",
> + ret);
> + return ret;
> + }
> + dsi->phy_ref_clk = clk;
> +
> + clk = devm_clk_get(dsi->dev, "rx_esc");
> + if (IS_ERR(clk)) {
> + ret = PTR_ERR(clk);
> + DRM_DEV_ERROR(dsi->dev, "Failed to get rx_esc clock: %d\n",
> + ret);
> + return ret;
> + }
> + dsi->rx_esc_clk = clk;
> +
> + clk = devm_clk_get(dsi->dev, "tx_esc");
> + if (IS_ERR(clk)) {
> + ret = PTR_ERR(clk);
> + DRM_DEV_ERROR(dsi->dev, "Failed to get tx_esc clock: %d\n",
> + ret);
> + return ret;
> + }
> + dsi->tx_esc_clk = clk;
> +
> + dsi->mux = devm_mux_control_get(dsi->dev, NULL);
> + if (IS_ERR(dsi->mux)) {
> + ret = PTR_ERR(dsi->mux);
> + if (ret != -EPROBE_DEFER)
> + DRM_DEV_ERROR(dsi->dev, "Failed to get mux: %d\n", ret);
> + return ret;
> + }
> +
> + base = devm_platform_ioremap_resource(pdev, 0);
> + if (IS_ERR(base))
> + return PTR_ERR(base);
> +
> + dsi->regmap =
> + devm_regmap_init_mmio(dsi->dev, base, &nwl_dsi_regmap_config);
> + if (IS_ERR(dsi->regmap)) {
> + ret = PTR_ERR(dsi->regmap);
> + DRM_DEV_ERROR(dsi->dev, "Failed to create NWL DSI regmap: %d\n",
> + ret);
> + return ret;
> + }
> +
> + dsi->irq = platform_get_irq(pdev, 0);
> + if (dsi->irq < 0) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to get device IRQ: %d\n",
> + dsi->irq);
> + return dsi->irq;
> + }
> +
> + dsi->rst_pclk = devm_reset_control_get_exclusive(dsi->dev, "pclk");
> + if (IS_ERR(dsi->rst_pclk)) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to get pclk reset: %ld\n",
> + PTR_ERR(dsi->rst_pclk));
> + return PTR_ERR(dsi->rst_pclk);
> + }
> + dsi->rst_byte = devm_reset_control_get_exclusive(dsi->dev, "byte");
> + if (IS_ERR(dsi->rst_byte)) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to get byte reset: %ld\n",
> + PTR_ERR(dsi->rst_byte));
> + return PTR_ERR(dsi->rst_byte);
> + }
> + dsi->rst_esc = devm_reset_control_get_exclusive(dsi->dev, "esc");
> + if (IS_ERR(dsi->rst_esc)) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to get esc reset: %ld\n",
> + PTR_ERR(dsi->rst_esc));
> + return PTR_ERR(dsi->rst_esc);
> + }
> + dsi->rst_dpi = devm_reset_control_get_exclusive(dsi->dev, "dpi");
> + if (IS_ERR(dsi->rst_dpi)) {
> + DRM_DEV_ERROR(dsi->dev, "Failed to get dpi reset: %ld\n",
> + PTR_ERR(dsi->rst_dpi));
> + return PTR_ERR(dsi->rst_dpi);
> + }
> + return 0;
> +}
> +
> +static int nwl_dsi_select_input(struct nwl_dsi *dsi)
> +{
> + struct device_node *remote;
> + u32 use_dcss = 1;
> + int ret;
> +
> + remote = of_graph_get_remote_node(dsi->dev->of_node, 0,
> + NWL_DSI_ENDPOINT_LCDIF);
> + if (remote) {
> + use_dcss = 0;
> + } else {
> + remote = of_graph_get_remote_node(dsi->dev->of_node, 0,
> + NWL_DSI_ENDPOINT_DCSS);
> + if (!remote) {
> + DRM_DEV_ERROR(dsi->dev,
> + "No valid input endpoint found\n");
> + return -EINVAL;
> + }
> + }
> +
> + DRM_DEV_INFO(dsi->dev, "Using %s as input source\n",
> + (use_dcss) ? "DCSS" : "LCDIF");
> + ret = mux_control_try_select(dsi->mux, use_dcss);
> + if (ret < 0)
> + DRM_DEV_ERROR(dsi->dev, "Failed to select input: %d\n", ret);
> +
> + of_node_put(remote);
> + return ret;
> +}
> +
> +static int nwl_dsi_deselect_input(struct nwl_dsi *dsi)
> +{
> + int ret;
> +
> + ret = mux_control_deselect(dsi->mux);
> + if (ret < 0)
> + DRM_DEV_ERROR(dsi->dev, "Failed to deselect input: %d\n", ret);
> +
> + return ret;
> +}
> +
> +static const struct drm_bridge_timings nwl_dsi_timings = {
> + .input_bus_flags = DRM_BUS_FLAG_DE_LOW,
> +};
> +
> +static const struct of_device_id nwl_dsi_dt_ids[] = {
> + { .compatible = "fsl,imx8mq-nwl-dsi", },
> + { /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, nwl_dsi_dt_ids);
> +
> +static const struct soc_device_attribute nwl_dsi_quirks_match[] = {
> + { .soc_id = "i.MX8MQ", .revision = "2.0",
> + .data = (void *)E11418_HS_MODE_QUIRK },
> + { /* sentinel. */ },
> +};
> +
> +static int nwl_dsi_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + const struct soc_device_attribute *attr;
> + struct nwl_dsi *dsi;
> + int ret;
> +
> + dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
> + if (!dsi)
> + return -ENOMEM;
> +
> + dsi->dev = dev;
> +
> + ret = nwl_dsi_parse_dt(dsi);
> + if (ret)
> + return ret;
> +
> + ret = devm_request_irq(dev, dsi->irq, nwl_dsi_irq_handler, 0,
> + dev_name(dev), dsi);
> + if (ret < 0) {
> + DRM_DEV_ERROR(dev, "Failed to request IRQ %d: %d\n", dsi->irq,
> + ret);
> + return ret;
> + }
> +
> + dsi->dsi_host.ops = &nwl_dsi_host_ops;
> + dsi->dsi_host.dev = dev;
> + ret = mipi_dsi_host_register(&dsi->dsi_host);
> + if (ret) {
> + DRM_DEV_ERROR(dev, "Failed to register MIPI host: %d\n", ret);
> + return ret;
> + }
> +
> + attr = soc_device_match(nwl_dsi_quirks_match);
> + if (attr)
> + dsi->quirks = (uintptr_t)attr->data;
> +
> + dsi->bridge.driver_private = dsi;
> + dsi->bridge.funcs = &nwl_dsi_bridge_funcs;
> + dsi->bridge.of_node = dev->of_node;
> + dsi->bridge.timings = &nwl_dsi_timings;
> +
> + dev_set_drvdata(dev, dsi);
> + pm_runtime_enable(dev);
> +
> + ret = nwl_dsi_select_input(dsi);
> + if (ret < 0) {
> + mipi_dsi_host_unregister(&dsi->dsi_host);
> + return ret;
> + }
> +
> + drm_bridge_add(&dsi->bridge);
> + return 0;
> +}
> +
> +static int nwl_dsi_remove(struct platform_device *pdev)
> +{
> + struct nwl_dsi *dsi = platform_get_drvdata(pdev);
> +
> + nwl_dsi_deselect_input(dsi);
> + mipi_dsi_host_unregister(&dsi->dsi_host);
> + drm_bridge_remove(&dsi->bridge);
> + pm_runtime_disable(&pdev->dev);
> + return 0;
> +}
> +
> +static struct platform_driver nwl_dsi_driver = {
> + .probe = nwl_dsi_probe,
> + .remove = nwl_dsi_remove,
> + .driver = {
> + .of_match_table = nwl_dsi_dt_ids,
> + .name = DRV_NAME,
> + },
> +};
> +
> +module_platform_driver(nwl_dsi_driver);
> +
> +MODULE_AUTHOR("NXP Semiconductor");
> +MODULE_AUTHOR("Purism SPC");
> +MODULE_DESCRIPTION("Northwest Logic MIPI-DSI driver");
> +MODULE_LICENSE("GPL"); /* GPLv2 or later */
> diff --git a/drivers/gpu/drm/bridge/nwl-dsi.h b/drivers/gpu/drm/bridge/nwl-dsi.h
> new file mode 100644
> index 000000000000..a247a8a11c7c
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/nwl-dsi.h
> @@ -0,0 +1,144 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * NWL MIPI DSI host driver
> + *
> + * Copyright (C) 2017 NXP
> + * Copyright (C) 2019 Purism SPC
> + */
> +#ifndef __NWL_DSI_H__
> +#define __NWL_DSI_H__
> +
> +/* DSI HOST registers */
> +#define NWL_DSI_CFG_NUM_LANES 0x0
> +#define NWL_DSI_CFG_NONCONTINUOUS_CLK 0x4
> +#define NWL_DSI_CFG_T_PRE 0x8
> +#define NWL_DSI_CFG_T_POST 0xc
> +#define NWL_DSI_CFG_TX_GAP 0x10
> +#define NWL_DSI_CFG_AUTOINSERT_EOTP 0x14
> +#define NWL_DSI_CFG_EXTRA_CMDS_AFTER_EOTP 0x18
> +#define NWL_DSI_CFG_HTX_TO_COUNT 0x1c
> +#define NWL_DSI_CFG_LRX_H_TO_COUNT 0x20
> +#define NWL_DSI_CFG_BTA_H_TO_COUNT 0x24
> +#define NWL_DSI_CFG_TWAKEUP 0x28
> +#define NWL_DSI_CFG_STATUS_OUT 0x2c
> +#define NWL_DSI_RX_ERROR_STATUS 0x30
> +
> +/* DSI DPI registers */
> +#define NWL_DSI_PIXEL_PAYLOAD_SIZE 0x200
> +#define NWL_DSI_PIXEL_FIFO_SEND_LEVEL 0x204
> +#define NWL_DSI_INTERFACE_COLOR_CODING 0x208
> +#define NWL_DSI_PIXEL_FORMAT 0x20c
> +#define NWL_DSI_VSYNC_POLARITY 0x210
> +#define NWL_DSI_VSYNC_POLARITY_ACTIVE_LOW 0
> +#define NWL_DSI_VSYNC_POLARITY_ACTIVE_HIGH BIT(1)
> +
> +#define NWL_DSI_HSYNC_POLARITY 0x214
> +#define NWL_DSI_HSYNC_POLARITY_ACTIVE_LOW 0
> +#define NWL_DSI_HSYNC_POLARITY_ACTIVE_HIGH BIT(1)
> +
> +#define NWL_DSI_VIDEO_MODE 0x218
> +#define NWL_DSI_HFP 0x21c
> +#define NWL_DSI_HBP 0x220
> +#define NWL_DSI_HSA 0x224
> +#define NWL_DSI_ENABLE_MULT_PKTS 0x228
> +#define NWL_DSI_VBP 0x22c
> +#define NWL_DSI_VFP 0x230
> +#define NWL_DSI_BLLP_MODE 0x234
> +#define NWL_DSI_USE_NULL_PKT_BLLP 0x238
> +#define NWL_DSI_VACTIVE 0x23c
> +#define NWL_DSI_VC 0x240
> +
> +/* DSI APB PKT control */
> +#define NWL_DSI_TX_PAYLOAD 0x280
> +#define NWL_DSI_PKT_CONTROL 0x284
> +#define NWL_DSI_SEND_PACKET 0x288
> +#define NWL_DSI_PKT_STATUS 0x28c
> +#define NWL_DSI_PKT_FIFO_WR_LEVEL 0x290
> +#define NWL_DSI_PKT_FIFO_RD_LEVEL 0x294
> +#define NWL_DSI_RX_PAYLOAD 0x298
> +#define NWL_DSI_RX_PKT_HEADER 0x29c
> +
> +/* DSI IRQ handling */
> +#define NWL_DSI_IRQ_STATUS 0x2a0
> +#define NWL_DSI_SM_NOT_IDLE BIT(0)
> +#define NWL_DSI_TX_PKT_DONE BIT(1)
> +#define NWL_DSI_DPHY_DIRECTION BIT(2)
> +#define NWL_DSI_TX_FIFO_OVFLW BIT(3)
> +#define NWL_DSI_TX_FIFO_UDFLW BIT(4)
> +#define NWL_DSI_RX_FIFO_OVFLW BIT(5)
> +#define NWL_DSI_RX_FIFO_UDFLW BIT(6)
> +#define NWL_DSI_RX_PKT_HDR_RCVD BIT(7)
> +#define NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD BIT(8)
> +#define NWL_DSI_BTA_TIMEOUT BIT(29)
> +#define NWL_DSI_LP_RX_TIMEOUT BIT(30)
> +#define NWL_DSI_HS_TX_TIMEOUT BIT(31)
> +
> +#define NWL_DSI_IRQ_STATUS2 0x2a4
> +#define NWL_DSI_SINGLE_BIT_ECC_ERR BIT(0)
> +#define NWL_DSI_MULTI_BIT_ECC_ERR BIT(1)
> +#define NWL_DSI_CRC_ERR BIT(2)
> +
> +#define NWL_DSI_IRQ_MASK 0x2a8
> +#define NWL_DSI_SM_NOT_IDLE_MASK BIT(0)
> +#define NWL_DSI_TX_PKT_DONE_MASK BIT(1)
> +#define NWL_DSI_DPHY_DIRECTION_MASK BIT(2)
> +#define NWL_DSI_TX_FIFO_OVFLW_MASK BIT(3)
> +#define NWL_DSI_TX_FIFO_UDFLW_MASK BIT(4)
> +#define NWL_DSI_RX_FIFO_OVFLW_MASK BIT(5)
> +#define NWL_DSI_RX_FIFO_UDFLW_MASK BIT(6)
> +#define NWL_DSI_RX_PKT_HDR_RCVD_MASK BIT(7)
> +#define NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD_MASK BIT(8)
> +#define NWL_DSI_BTA_TIMEOUT_MASK BIT(29)
> +#define NWL_DSI_LP_RX_TIMEOUT_MASK BIT(30)
> +#define NWL_DSI_HS_TX_TIMEOUT_MASK BIT(31)
> +
> +#define NWL_DSI_IRQ_MASK2 0x2ac
> +#define NWL_DSI_SINGLE_BIT_ECC_ERR_MASK BIT(0)
> +#define NWL_DSI_MULTI_BIT_ECC_ERR_MASK BIT(1)
> +#define NWL_DSI_CRC_ERR_MASK BIT(2)
> +
> +/*
> + * PKT_CONTROL format:
> + * [15: 0] - word count
> + * [17:16] - virtual channel
> + * [23:18] - data type
> + * [24] - LP or HS select (0 - LP, 1 - HS)
> + * [25] - perform BTA after packet is sent
> + * [26] - perform BTA only, no packet tx
> + */
> +#define NWL_DSI_WC(x) FIELD_PREP(GENMASK(15, 0), (x))
> +#define NWL_DSI_TX_VC(x) FIELD_PREP(GENMASK(17, 16), (x))
> +#define NWL_DSI_TX_DT(x) FIELD_PREP(GENMASK(23, 18), (x))
> +#define NWL_DSI_HS_SEL(x) FIELD_PREP(GENMASK(24, 24), (x))
> +#define NWL_DSI_BTA_TX(x) FIELD_PREP(GENMASK(25, 25), (x))
> +#define NWL_DSI_BTA_NO_TX(x) FIELD_PREP(GENMASK(26, 26), (x))
> +
> +/*
> + * RX_PKT_HEADER format:
> + * [15: 0] - word count
> + * [21:16] - data type
> + * [23:22] - virtual channel
> + */
> +#define NWL_DSI_RX_DT(x) FIELD_GET(GENMASK(21, 16), (x))
> +#define NWL_DSI_RX_VC(x) FIELD_GET(GENMASK(23, 22), (x))
> +
> +/* DSI Video mode */
> +#define NWL_DSI_VM_BURST_MODE_WITH_SYNC_PULSES 0
> +#define NWL_DSI_VM_NON_BURST_MODE_WITH_SYNC_EVENTS BIT(0)
> +#define NWL_DSI_VM_BURST_MODE BIT(1)
> +
> +/* * DPI color coding */
> +#define NWL_DSI_DPI_16_BIT_565_PACKED 0
> +#define NWL_DSI_DPI_16_BIT_565_ALIGNED 1
> +#define NWL_DSI_DPI_16_BIT_565_SHIFTED 2
> +#define NWL_DSI_DPI_18_BIT_PACKED 3
> +#define NWL_DSI_DPI_18_BIT_ALIGNED 4
> +#define NWL_DSI_DPI_24_BIT 5
> +
> +/* * DPI Pixel format */
> +#define NWL_DSI_PIXEL_FORMAT_16 0
> +#define NWL_DSI_PIXEL_FORMAT_18 BIT(0)
> +#define NWL_DSI_PIXEL_FORMAT_18L BIT(1)
> +#define NWL_DSI_PIXEL_FORMAT_24 (BIT(0) | BIT(1))
> +
> +#endif /* __NWL_DSI_H__ */
> --
> 2.23.0
>