Merge tag 'io_uring-5.11-2021-01-16' of git://git.kernel.dk/linux-block

[linux/fpc-iii.git] / drivers / gpu / drm / bridge / cdns-dsi.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright: 2017 Cadence Design Systems, Inc.
 *
 * Author: Boris Brezillon <boris.brezillon@bootlin.com>
 */

#include <drm/drm_atomic_helper.h>
#include <drm/drm_bridge.h>
#include <drm/drm_drv.h>
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_panel.h>
#include <drm/drm_probe_helper.h>
#include <video/mipi_display.h>

#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_graph.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>

#include <linux/phy/phy.h>
#include <linux/phy/phy-mipi-dphy.h>

#define IP_CONF                         0x0
#define SP_HS_FIFO_DEPTH(x)             (((x) & GENMASK(30, 26)) >> 26)
#define SP_LP_FIFO_DEPTH(x)             (((x) & GENMASK(25, 21)) >> 21)
#define VRS_FIFO_DEPTH(x)               (((x) & GENMASK(20, 16)) >> 16)
#define DIRCMD_FIFO_DEPTH(x)            (((x) & GENMASK(15, 13)) >> 13)
#define SDI_IFACE_32                    BIT(12)
#define INTERNAL_DATAPATH_32            (0 << 10)
#define INTERNAL_DATAPATH_16            (1 << 10)
#define INTERNAL_DATAPATH_8             (3 << 10)
#define INTERNAL_DATAPATH_SIZE          ((x) & GENMASK(11, 10))
#define NUM_IFACE(x)                    ((((x) & GENMASK(9, 8)) >> 8) + 1)
#define MAX_LANE_NB(x)                  (((x) & GENMASK(7, 6)) >> 6)
#define RX_FIFO_DEPTH(x)                ((x) & GENMASK(5, 0))

#define MCTL_MAIN_DATA_CTL              0x4
#define TE_MIPI_POLLING_EN              BIT(25)
#define TE_HW_POLLING_EN                BIT(24)
#define DISP_EOT_GEN                    BIT(18)
#define HOST_EOT_GEN                    BIT(17)
#define DISP_GEN_CHECKSUM               BIT(16)
#define DISP_GEN_ECC                    BIT(15)
#define BTA_EN                          BIT(14)
#define READ_EN                         BIT(13)
#define REG_TE_EN                       BIT(12)
#define IF_TE_EN(x)                     BIT(8 + (x))
#define TVG_SEL                         BIT(6)
#define VID_EN                          BIT(5)
#define IF_VID_SELECT(x)                ((x) << 2)
#define IF_VID_SELECT_MASK              GENMASK(3, 2)
#define IF_VID_MODE                     BIT(1)
#define LINK_EN                         BIT(0)

#define MCTL_MAIN_PHY_CTL               0x8
#define HS_INVERT_DAT(x)                BIT(19 + ((x) * 2))
#define SWAP_PINS_DAT(x)                BIT(18 + ((x) * 2))
#define HS_INVERT_CLK                   BIT(17)
#define SWAP_PINS_CLK                   BIT(16)
#define HS_SKEWCAL_EN                   BIT(15)
#define WAIT_BURST_TIME(x)              ((x) << 10)
#define DATA_ULPM_EN(x)                 BIT(6 + (x))
#define CLK_ULPM_EN                     BIT(5)
#define CLK_CONTINUOUS                  BIT(4)
#define DATA_LANE_EN(x)                 BIT((x) - 1)

#define MCTL_MAIN_EN                    0xc
#define DATA_FORCE_STOP                 BIT(17)
#define CLK_FORCE_STOP                  BIT(16)
#define IF_EN(x)                        BIT(13 + (x))
#define DATA_LANE_ULPM_REQ(l)           BIT(9 + (l))
#define CLK_LANE_ULPM_REQ               BIT(8)
#define DATA_LANE_START(x)              BIT(4 + (x))
#define CLK_LANE_EN                     BIT(3)
#define PLL_START                       BIT(0)

#define MCTL_DPHY_CFG0                  0x10
#define DPHY_C_RSTB                     BIT(20)
#define DPHY_D_RSTB(x)                  GENMASK(15 + (x), 16)
#define DPHY_PLL_PDN                    BIT(10)
#define DPHY_CMN_PDN                    BIT(9)
#define DPHY_C_PDN                      BIT(8)
#define DPHY_D_PDN(x)                   GENMASK(3 + (x), 4)
#define DPHY_ALL_D_PDN                  GENMASK(7, 4)
#define DPHY_PLL_PSO                    BIT(1)
#define DPHY_CMN_PSO                    BIT(0)

#define MCTL_DPHY_TIMEOUT1              0x14
#define HSTX_TIMEOUT(x)                 ((x) << 4)
#define HSTX_TIMEOUT_MAX                GENMASK(17, 0)
#define CLK_DIV(x)                      (x)
#define CLK_DIV_MAX                     GENMASK(3, 0)

#define MCTL_DPHY_TIMEOUT2              0x18
#define LPRX_TIMEOUT(x)                 (x)

#define MCTL_ULPOUT_TIME                0x1c
#define DATA_LANE_ULPOUT_TIME(x)        ((x) << 9)
#define CLK_LANE_ULPOUT_TIME(x)         (x)

#define MCTL_3DVIDEO_CTL                0x20
#define VID_VSYNC_3D_EN                 BIT(7)
#define VID_VSYNC_3D_LR                 BIT(5)
#define VID_VSYNC_3D_SECOND_EN          BIT(4)
#define VID_VSYNC_3DFORMAT_LINE         (0 << 2)
#define VID_VSYNC_3DFORMAT_FRAME        (1 << 2)
#define VID_VSYNC_3DFORMAT_PIXEL        (2 << 2)
#define VID_VSYNC_3DMODE_OFF            0
#define VID_VSYNC_3DMODE_PORTRAIT       1
#define VID_VSYNC_3DMODE_LANDSCAPE      2

#define MCTL_MAIN_STS                   0x24
#define MCTL_MAIN_STS_CTL               0x130
#define MCTL_MAIN_STS_CLR               0x150
#define MCTL_MAIN_STS_FLAG              0x170
#define HS_SKEWCAL_DONE                 BIT(11)
#define IF_UNTERM_PKT_ERR(x)            BIT(8 + (x))
#define LPRX_TIMEOUT_ERR                BIT(7)
#define HSTX_TIMEOUT_ERR                BIT(6)
#define DATA_LANE_RDY(l)                BIT(2 + (l))
#define CLK_LANE_RDY                    BIT(1)
#define PLL_LOCKED                      BIT(0)

#define MCTL_DPHY_ERR                   0x28
#define MCTL_DPHY_ERR_CTL1              0x148
#define MCTL_DPHY_ERR_CLR               0x168
#define MCTL_DPHY_ERR_FLAG              0x188
#define ERR_CONT_LP(x, l)               BIT(18 + ((x) * 4) + (l))
#define ERR_CONTROL(l)                  BIT(14 + (l))
#define ERR_SYNESC(l)                   BIT(10 + (l))
#define ERR_ESC(l)                      BIT(6 + (l))

#define MCTL_DPHY_ERR_CTL2              0x14c
#define ERR_CONT_LP_EDGE(x, l)          BIT(12 + ((x) * 4) + (l))
#define ERR_CONTROL_EDGE(l)             BIT(8 + (l))
#define ERR_SYN_ESC_EDGE(l)             BIT(4 + (l))
#define ERR_ESC_EDGE(l)                 BIT(0 + (l))

#define MCTL_LANE_STS                   0x2c
#define PPI_C_TX_READY_HS               BIT(18)
#define DPHY_PLL_LOCK                   BIT(17)
#define PPI_D_RX_ULPS_ESC(x)            (((x) & GENMASK(15, 12)) >> 12)
#define LANE_STATE_START                0
#define LANE_STATE_IDLE                 1
#define LANE_STATE_WRITE                2
#define LANE_STATE_ULPM                 3
#define LANE_STATE_READ                 4
#define DATA_LANE_STATE(l, val)         \
        (((val) >> (2 + 2 * (l) + ((l) ? 1 : 0))) & GENMASK((l) ? 1 : 2, 0))
#define CLK_LANE_STATE_HS               2
#define CLK_LANE_STATE(val)             ((val) & GENMASK(1, 0))

#define DSC_MODE_CTL                    0x30
#define DSC_MODE_EN                     BIT(0)

#define DSC_CMD_SEND                    0x34
#define DSC_SEND_PPS                    BIT(0)
#define DSC_EXECUTE_QUEUE               BIT(1)

#define DSC_PPS_WRDAT                   0x38

#define DSC_MODE_STS                    0x3c
#define DSC_PPS_DONE                    BIT(1)
#define DSC_EXEC_DONE                   BIT(2)

#define CMD_MODE_CTL                    0x70
#define IF_LP_EN(x)                     BIT(9 + (x))
#define IF_VCHAN_ID(x, c)               ((c) << ((x) * 2))

#define CMD_MODE_CTL2                   0x74
#define TE_TIMEOUT(x)                   ((x) << 11)
#define FILL_VALUE(x)                   ((x) << 3)
#define ARB_IF_WITH_HIGHEST_PRIORITY(x) ((x) << 1)
#define ARB_ROUND_ROBIN_MODE            BIT(0)

#define CMD_MODE_STS                    0x78
#define CMD_MODE_STS_CTL                0x134
#define CMD_MODE_STS_CLR                0x154
#define CMD_MODE_STS_FLAG               0x174
#define ERR_IF_UNDERRUN(x)              BIT(4 + (x))
#define ERR_UNWANTED_READ               BIT(3)
#define ERR_TE_MISS                     BIT(2)
#define ERR_NO_TE                       BIT(1)
#define CSM_RUNNING                     BIT(0)

#define DIRECT_CMD_SEND                 0x80

#define DIRECT_CMD_MAIN_SETTINGS        0x84
#define TRIGGER_VAL(x)                  ((x) << 25)
#define CMD_LP_EN                       BIT(24)
#define CMD_SIZE(x)                     ((x) << 16)
#define CMD_VCHAN_ID(x)                 ((x) << 14)
#define CMD_DATATYPE(x)                 ((x) << 8)
#define CMD_LONG                        BIT(3)
#define WRITE_CMD                       0
#define READ_CMD                        1
#define TE_REQ                          4
#define TRIGGER_REQ                     5
#define BTA_REQ                         6

#define DIRECT_CMD_STS                  0x88
#define DIRECT_CMD_STS_CTL              0x138
#define DIRECT_CMD_STS_CLR              0x158
#define DIRECT_CMD_STS_FLAG             0x178
#define RCVD_ACK_VAL(val)               ((val) >> 16)
#define RCVD_TRIGGER_VAL(val)           (((val) & GENMASK(14, 11)) >> 11)
#define READ_COMPLETED_WITH_ERR         BIT(10)
#define BTA_FINISHED                    BIT(9)
#define BTA_COMPLETED                   BIT(8)
#define TE_RCVD                         BIT(7)
#define TRIGGER_RCVD                    BIT(6)
#define ACK_WITH_ERR_RCVD               BIT(5)
#define ACK_RCVD                        BIT(4)
#define READ_COMPLETED                  BIT(3)
#define TRIGGER_COMPLETED               BIT(2)
#define WRITE_COMPLETED                 BIT(1)
#define SENDING_CMD                     BIT(0)

#define DIRECT_CMD_STOP_READ            0x8c

#define DIRECT_CMD_WRDATA               0x90

#define DIRECT_CMD_FIFO_RST             0x94

#define DIRECT_CMD_RDDATA               0xa0

#define DIRECT_CMD_RD_PROPS             0xa4
#define RD_DCS                          BIT(18)
#define RD_VCHAN_ID(val)                (((val) >> 16) & GENMASK(1, 0))
#define RD_SIZE(val)                    ((val) & GENMASK(15, 0))

#define DIRECT_CMD_RD_STS               0xa8
#define DIRECT_CMD_RD_STS_CTL           0x13c
#define DIRECT_CMD_RD_STS_CLR           0x15c
#define DIRECT_CMD_RD_STS_FLAG          0x17c
#define ERR_EOT_WITH_ERR                BIT(8)
#define ERR_MISSING_EOT                 BIT(7)
#define ERR_WRONG_LENGTH                BIT(6)
#define ERR_OVERSIZE                    BIT(5)
#define ERR_RECEIVE                     BIT(4)
#define ERR_UNDECODABLE                 BIT(3)
#define ERR_CHECKSUM                    BIT(2)
#define ERR_UNCORRECTABLE               BIT(1)
#define ERR_FIXED                       BIT(0)

#define VID_MAIN_CTL                    0xb0
#define VID_IGNORE_MISS_VSYNC           BIT(31)
#define VID_FIELD_SW                    BIT(28)
#define VID_INTERLACED_EN               BIT(27)
#define RECOVERY_MODE(x)                ((x) << 25)
#define RECOVERY_MODE_NEXT_HSYNC        0
#define RECOVERY_MODE_NEXT_STOP_POINT   2
#define RECOVERY_MODE_NEXT_VSYNC        3
#define REG_BLKEOL_MODE(x)              ((x) << 23)
#define REG_BLKLINE_MODE(x)             ((x) << 21)
#define REG_BLK_MODE_NULL_PKT           0
#define REG_BLK_MODE_BLANKING_PKT       1
#define REG_BLK_MODE_LP                 2
#define SYNC_PULSE_HORIZONTAL           BIT(20)
#define SYNC_PULSE_ACTIVE               BIT(19)
#define BURST_MODE                      BIT(18)
#define VID_PIXEL_MODE_MASK             GENMASK(17, 14)
#define VID_PIXEL_MODE_RGB565           (0 << 14)
#define VID_PIXEL_MODE_RGB666_PACKED    (1 << 14)
#define VID_PIXEL_MODE_RGB666           (2 << 14)
#define VID_PIXEL_MODE_RGB888           (3 << 14)
#define VID_PIXEL_MODE_RGB101010        (4 << 14)
#define VID_PIXEL_MODE_RGB121212        (5 << 14)
#define VID_PIXEL_MODE_YUV420           (8 << 14)
#define VID_PIXEL_MODE_YUV422_PACKED    (9 << 14)
#define VID_PIXEL_MODE_YUV422           (10 << 14)
#define VID_PIXEL_MODE_YUV422_24B       (11 << 14)
#define VID_PIXEL_MODE_DSC_COMP         (12 << 14)
#define VID_DATATYPE(x)                 ((x) << 8)
#define VID_VIRTCHAN_ID(iface, x)       ((x) << (4 + (iface) * 2))
#define STOP_MODE(x)                    ((x) << 2)
#define START_MODE(x)                   (x)

#define VID_VSIZE1                      0xb4
#define VFP_LEN(x)                      ((x) << 12)
#define VBP_LEN(x)                      ((x) << 6)
#define VSA_LEN(x)                      (x)

#define VID_VSIZE2                      0xb8
#define VACT_LEN(x)                     (x)

#define VID_HSIZE1                      0xc0
#define HBP_LEN(x)                      ((x) << 16)
#define HSA_LEN(x)                      (x)

#define VID_HSIZE2                      0xc4
#define HFP_LEN(x)                      ((x) << 16)
#define HACT_LEN(x)                     (x)

#define VID_BLKSIZE1                    0xcc
#define BLK_EOL_PKT_LEN(x)              ((x) << 15)
#define BLK_LINE_EVENT_PKT_LEN(x)       (x)

#define VID_BLKSIZE2                    0xd0
#define BLK_LINE_PULSE_PKT_LEN(x)       (x)

#define VID_PKT_TIME                    0xd8
#define BLK_EOL_DURATION(x)             (x)

#define VID_DPHY_TIME                   0xdc
#define REG_WAKEUP_TIME(x)              ((x) << 17)
#define REG_LINE_DURATION(x)            (x)

#define VID_ERR_COLOR1                  0xe0
#define COL_GREEN(x)                    ((x) << 12)
#define COL_RED(x)                      (x)

#define VID_ERR_COLOR2                  0xe4
#define PAD_VAL(x)                      ((x) << 12)
#define COL_BLUE(x)                     (x)

#define VID_VPOS                        0xe8
#define LINE_VAL(val)                   (((val) & GENMASK(14, 2)) >> 2)
#define LINE_POS(val)                   ((val) & GENMASK(1, 0))

#define VID_HPOS                        0xec
#define HORIZ_VAL(val)                  (((val) & GENMASK(17, 3)) >> 3)
#define HORIZ_POS(val)                  ((val) & GENMASK(2, 0))

#define VID_MODE_STS                    0xf0
#define VID_MODE_STS_CTL                0x140
#define VID_MODE_STS_CLR                0x160
#define VID_MODE_STS_FLAG               0x180
#define VSG_RECOVERY                    BIT(10)
#define ERR_VRS_WRONG_LEN               BIT(9)
#define ERR_LONG_READ                   BIT(8)
#define ERR_LINE_WRITE                  BIT(7)
#define ERR_BURST_WRITE                 BIT(6)
#define ERR_SMALL_HEIGHT                BIT(5)
#define ERR_SMALL_LEN                   BIT(4)
#define ERR_MISSING_VSYNC               BIT(3)
#define ERR_MISSING_HSYNC               BIT(2)
#define ERR_MISSING_DATA                BIT(1)
#define VSG_RUNNING                     BIT(0)

#define VID_VCA_SETTING1                0xf4
#define BURST_LP                        BIT(16)
#define MAX_BURST_LIMIT(x)              (x)

#define VID_VCA_SETTING2                0xf8
#define MAX_LINE_LIMIT(x)               ((x) << 16)
#define EXACT_BURST_LIMIT(x)            (x)

#define TVG_CTL                         0xfc
#define TVG_STRIPE_SIZE(x)              ((x) << 5)
#define TVG_MODE_MASK                   GENMASK(4, 3)
#define TVG_MODE_SINGLE_COLOR           (0 << 3)
#define TVG_MODE_VSTRIPES               (2 << 3)
#define TVG_MODE_HSTRIPES               (3 << 3)
#define TVG_STOPMODE_MASK               GENMASK(2, 1)
#define TVG_STOPMODE_EOF                (0 << 1)
#define TVG_STOPMODE_EOL                (1 << 1)
#define TVG_STOPMODE_NOW                (2 << 1)
#define TVG_RUN                         BIT(0)

#define TVG_IMG_SIZE                    0x100
#define TVG_NBLINES(x)                  ((x) << 16)
#define TVG_LINE_SIZE(x)                (x)

#define TVG_COLOR1                      0x104
#define TVG_COL1_GREEN(x)               ((x) << 12)
#define TVG_COL1_RED(x)                 (x)

#define TVG_COLOR1_BIS                  0x108
#define TVG_COL1_BLUE(x)                (x)

#define TVG_COLOR2                      0x10c
#define TVG_COL2_GREEN(x)               ((x) << 12)
#define TVG_COL2_RED(x)                 (x)

#define TVG_COLOR2_BIS                  0x110
#define TVG_COL2_BLUE(x)                (x)

#define TVG_STS                         0x114
#define TVG_STS_CTL                     0x144
#define TVG_STS_CLR                     0x164
#define TVG_STS_FLAG                    0x184
#define TVG_STS_RUNNING                 BIT(0)

#define STS_CTL_EDGE(e)                 ((e) << 16)

#define DPHY_LANES_MAP                  0x198
#define DAT_REMAP_CFG(b, l)             ((l) << ((b) * 8))

#define DPI_IRQ_EN                      0x1a0
#define DPI_IRQ_CLR                     0x1a4
#define DPI_IRQ_STS                     0x1a8
#define PIXEL_BUF_OVERFLOW              BIT(0)

#define DPI_CFG                         0x1ac
#define DPI_CFG_FIFO_DEPTH(x)           ((x) >> 16)
#define DPI_CFG_FIFO_LEVEL(x)           ((x) & GENMASK(15, 0))

#define TEST_GENERIC                    0x1f0
#define TEST_STATUS(x)                  ((x) >> 16)
#define TEST_CTRL(x)                    (x)

#define ID_REG                          0x1fc
#define REV_VENDOR_ID(x)                (((x) & GENMASK(31, 20)) >> 20)
#define REV_PRODUCT_ID(x)               (((x) & GENMASK(19, 12)) >> 12)
#define REV_HW(x)                       (((x) & GENMASK(11, 8)) >> 8)
#define REV_MAJOR(x)                    (((x) & GENMASK(7, 4)) >> 4)
#define REV_MINOR(x)                    ((x) & GENMASK(3, 0))

#define DSI_OUTPUT_PORT                 0
#define DSI_INPUT_PORT(inputid)         (1 + (inputid))

#define DSI_HBP_FRAME_OVERHEAD          12
#define DSI_HSA_FRAME_OVERHEAD          14
#define DSI_HFP_FRAME_OVERHEAD          6
#define DSI_HSS_VSS_VSE_FRAME_OVERHEAD  4
#define DSI_BLANKING_FRAME_OVERHEAD     6
#define DSI_NULL_FRAME_OVERHEAD         6
#define DSI_EOT_PKT_SIZE                4

struct cdns_dsi_output {
        struct mipi_dsi_device *dev;
        struct drm_panel *panel;
        struct drm_bridge *bridge;
        union phy_configure_opts phy_opts;
};

enum cdns_dsi_input_id {
        CDNS_SDI_INPUT,
        CDNS_DPI_INPUT,
        CDNS_DSC_INPUT,
};

struct cdns_dsi_cfg {
        unsigned int hfp;
        unsigned int hsa;
        unsigned int hbp;
        unsigned int hact;
        unsigned int htotal;
};

struct cdns_dsi_input {
        enum cdns_dsi_input_id id;
        struct drm_bridge bridge;
};

struct cdns_dsi {
        struct mipi_dsi_host base;
        void __iomem *regs;
        struct cdns_dsi_input input;
        struct cdns_dsi_output output;
        unsigned int direct_cmd_fifo_depth;
        unsigned int rx_fifo_depth;
        struct completion direct_cmd_comp;
        struct clk *dsi_p_clk;
        struct reset_control *dsi_p_rst;
        struct clk *dsi_sys_clk;
        bool link_initialized;
        struct phy *dphy;
};

static inline struct cdns_dsi *input_to_dsi(struct cdns_dsi_input *input)
{
        return container_of(input, struct cdns_dsi, input);
}

static inline struct cdns_dsi *to_cdns_dsi(struct mipi_dsi_host *host)
{
        return container_of(host, struct cdns_dsi, base);
}

static inline struct cdns_dsi_input *
bridge_to_cdns_dsi_input(struct drm_bridge *bridge)
{
        return container_of(bridge, struct cdns_dsi_input, bridge);
}

static unsigned int mode_to_dpi_hfp(const struct drm_display_mode *mode,
                                    bool mode_valid_check)
{
        if (mode_valid_check)
                return mode->hsync_start - mode->hdisplay;

        return mode->crtc_hsync_start - mode->crtc_hdisplay;
}

static unsigned int dpi_to_dsi_timing(unsigned int dpi_timing,
                                      unsigned int dpi_bpp,
                                      unsigned int dsi_pkt_overhead)
{
        unsigned int dsi_timing = DIV_ROUND_UP(dpi_timing * dpi_bpp, 8);

        if (dsi_timing < dsi_pkt_overhead)
                dsi_timing = 0;
        else
                dsi_timing -= dsi_pkt_overhead;

        return dsi_timing;
}

static int cdns_dsi_mode2cfg(struct cdns_dsi *dsi,
                             const struct drm_display_mode *mode,
                             struct cdns_dsi_cfg *dsi_cfg,
                             bool mode_valid_check)
{
        struct cdns_dsi_output *output = &dsi->output;
        unsigned int tmp;
        bool sync_pulse = false;
        int bpp;

        memset(dsi_cfg, 0, sizeof(*dsi_cfg));

        if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
                sync_pulse = true;

        bpp = mipi_dsi_pixel_format_to_bpp(output->dev->format);

        if (mode_valid_check)
                tmp = mode->htotal -
                      (sync_pulse ? mode->hsync_end : mode->hsync_start);
        else
                tmp = mode->crtc_htotal -
                      (sync_pulse ?
                       mode->crtc_hsync_end : mode->crtc_hsync_start);

        dsi_cfg->hbp = dpi_to_dsi_timing(tmp, bpp, DSI_HBP_FRAME_OVERHEAD);

        if (sync_pulse) {
                if (mode_valid_check)
                        tmp = mode->hsync_end - mode->hsync_start;
                else
                        tmp = mode->crtc_hsync_end - mode->crtc_hsync_start;

                dsi_cfg->hsa = dpi_to_dsi_timing(tmp, bpp,
                                                 DSI_HSA_FRAME_OVERHEAD);
        }

        dsi_cfg->hact = dpi_to_dsi_timing(mode_valid_check ?
                                          mode->hdisplay : mode->crtc_hdisplay,
                                          bpp, 0);
        dsi_cfg->hfp = dpi_to_dsi_timing(mode_to_dpi_hfp(mode, mode_valid_check),
                                         bpp, DSI_HFP_FRAME_OVERHEAD);

        return 0;
}

static int cdns_dsi_adjust_phy_config(struct cdns_dsi *dsi,
                              struct cdns_dsi_cfg *dsi_cfg,
                              struct phy_configure_opts_mipi_dphy *phy_cfg,
                              const struct drm_display_mode *mode,
                              bool mode_valid_check)
{
        struct cdns_dsi_output *output = &dsi->output;
        unsigned long long dlane_bps;
        unsigned long adj_dsi_htotal;
        unsigned long dsi_htotal;
        unsigned long dpi_htotal;
        unsigned long dpi_hz;
        unsigned int dsi_hfp_ext;
        unsigned int lanes = output->dev->lanes;

        dsi_htotal = dsi_cfg->hbp + DSI_HBP_FRAME_OVERHEAD;
        if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
                dsi_htotal += dsi_cfg->hsa + DSI_HSA_FRAME_OVERHEAD;

        dsi_htotal += dsi_cfg->hact;
        dsi_htotal += dsi_cfg->hfp + DSI_HFP_FRAME_OVERHEAD;

        /*
         * Make sure DSI htotal is aligned on a lane boundary when calculating
         * the expected data rate. This is done by extending HFP in case of
         * misalignment.
         */
        adj_dsi_htotal = dsi_htotal;
        if (dsi_htotal % lanes)
                adj_dsi_htotal += lanes - (dsi_htotal % lanes);

        dpi_hz = (mode_valid_check ? mode->clock : mode->crtc_clock) * 1000;
        dlane_bps = (unsigned long long)dpi_hz * adj_dsi_htotal;

        /* data rate in bytes/sec is not an integer, refuse the mode. */
        dpi_htotal = mode_valid_check ? mode->htotal : mode->crtc_htotal;
        if (do_div(dlane_bps, lanes * dpi_htotal))
                return -EINVAL;

        /* data rate was in bytes/sec, convert to bits/sec. */
        phy_cfg->hs_clk_rate = dlane_bps * 8;

        dsi_hfp_ext = adj_dsi_htotal - dsi_htotal;
        dsi_cfg->hfp += dsi_hfp_ext;
        dsi_cfg->htotal = dsi_htotal + dsi_hfp_ext;

        return 0;
}

static int cdns_dsi_check_conf(struct cdns_dsi *dsi,
                               const struct drm_display_mode *mode,
                               struct cdns_dsi_cfg *dsi_cfg,
                               bool mode_valid_check)
{
        struct cdns_dsi_output *output = &dsi->output;
        struct phy_configure_opts_mipi_dphy *phy_cfg = &output->phy_opts.mipi_dphy;
        unsigned long dsi_hss_hsa_hse_hbp;
        unsigned int nlanes = output->dev->lanes;
        int ret;

        ret = cdns_dsi_mode2cfg(dsi, mode, dsi_cfg, mode_valid_check);
        if (ret)
                return ret;

        phy_mipi_dphy_get_default_config(mode->crtc_clock * 1000,
                                         mipi_dsi_pixel_format_to_bpp(output->dev->format),
                                         nlanes, phy_cfg);

        ret = cdns_dsi_adjust_phy_config(dsi, dsi_cfg, phy_cfg, mode, mode_valid_check);
        if (ret)
                return ret;

        ret = phy_validate(dsi->dphy, PHY_MODE_MIPI_DPHY, 0, &output->phy_opts);
        if (ret)
                return ret;

        dsi_hss_hsa_hse_hbp = dsi_cfg->hbp + DSI_HBP_FRAME_OVERHEAD;
        if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
                dsi_hss_hsa_hse_hbp += dsi_cfg->hsa + DSI_HSA_FRAME_OVERHEAD;

        /*
         * Make sure DPI(HFP) > DSI(HSS+HSA+HSE+HBP) to guarantee that the FIFO
         * is empty before we start a receiving a new line on the DPI
         * interface.
         */
        if ((u64)phy_cfg->hs_clk_rate *
            mode_to_dpi_hfp(mode, mode_valid_check) * nlanes <
            (u64)dsi_hss_hsa_hse_hbp *
            (mode_valid_check ? mode->clock : mode->crtc_clock) * 1000)
                return -EINVAL;

        return 0;
}

static int cdns_dsi_bridge_attach(struct drm_bridge *bridge,
                                  enum drm_bridge_attach_flags flags)
{
        struct cdns_dsi_input *input = bridge_to_cdns_dsi_input(bridge);
        struct cdns_dsi *dsi = input_to_dsi(input);
        struct cdns_dsi_output *output = &dsi->output;

        if (!drm_core_check_feature(bridge->dev, DRIVER_ATOMIC)) {
                dev_err(dsi->base.dev,
                        "cdns-dsi driver is only compatible with DRM devices supporting atomic updates");
                return -ENOTSUPP;
        }

        return drm_bridge_attach(bridge->encoder, output->bridge, bridge,
                                 flags);
}

static enum drm_mode_status
cdns_dsi_bridge_mode_valid(struct drm_bridge *bridge,
                           const struct drm_display_info *info,
                           const struct drm_display_mode *mode)
{
        struct cdns_dsi_input *input = bridge_to_cdns_dsi_input(bridge);
        struct cdns_dsi *dsi = input_to_dsi(input);
        struct cdns_dsi_output *output = &dsi->output;
        struct cdns_dsi_cfg dsi_cfg;
        int bpp, ret;

        /*
         * VFP_DSI should be less than VFP_DPI and VFP_DSI should be at
         * least 1.
         */
        if (mode->vtotal - mode->vsync_end < 2)
                return MODE_V_ILLEGAL;

        /* VSA_DSI = VSA_DPI and must be at least 2. */
        if (mode->vsync_end - mode->vsync_start < 2)
                return MODE_V_ILLEGAL;

        /* HACT must be 32-bits aligned. */
        bpp = mipi_dsi_pixel_format_to_bpp(output->dev->format);
        if ((mode->hdisplay * bpp) % 32)
                return MODE_H_ILLEGAL;

        ret = cdns_dsi_check_conf(dsi, mode, &dsi_cfg, true);
        if (ret)
                return MODE_BAD;

        return MODE_OK;
}

static void cdns_dsi_bridge_disable(struct drm_bridge *bridge)
{
        struct cdns_dsi_input *input = bridge_to_cdns_dsi_input(bridge);
        struct cdns_dsi *dsi = input_to_dsi(input);
        u32 val;

        val = readl(dsi->regs + MCTL_MAIN_DATA_CTL);
        val &= ~(IF_VID_SELECT_MASK | IF_VID_MODE | VID_EN | HOST_EOT_GEN |
                 DISP_EOT_GEN);
        writel(val, dsi->regs + MCTL_MAIN_DATA_CTL);

        val = readl(dsi->regs + MCTL_MAIN_EN) & ~IF_EN(input->id);
        writel(val, dsi->regs + MCTL_MAIN_EN);
        pm_runtime_put(dsi->base.dev);
}

static void cdns_dsi_hs_init(struct cdns_dsi *dsi)
{
        struct cdns_dsi_output *output = &dsi->output;
        u32 status;

        /*
         * Power all internal DPHY blocks down and maintain their reset line
         * asserted before changing the DPHY config.
         */
        writel(DPHY_CMN_PSO | DPHY_PLL_PSO | DPHY_ALL_D_PDN | DPHY_C_PDN |
               DPHY_CMN_PDN | DPHY_PLL_PDN,
               dsi->regs + MCTL_DPHY_CFG0);

        phy_init(dsi->dphy);
        phy_set_mode(dsi->dphy, PHY_MODE_MIPI_DPHY);
        phy_configure(dsi->dphy, &output->phy_opts);
        phy_power_on(dsi->dphy);

        /* Activate the PLL and wait until it's locked. */
        writel(PLL_LOCKED, dsi->regs + MCTL_MAIN_STS_CLR);
        writel(DPHY_CMN_PSO | DPHY_ALL_D_PDN | DPHY_C_PDN | DPHY_CMN_PDN,
               dsi->regs + MCTL_DPHY_CFG0);
        WARN_ON_ONCE(readl_poll_timeout(dsi->regs + MCTL_MAIN_STS, status,
                                        status & PLL_LOCKED, 100, 100));
        /* De-assert data and clock reset lines. */
        writel(DPHY_CMN_PSO | DPHY_ALL_D_PDN | DPHY_C_PDN | DPHY_CMN_PDN |
               DPHY_D_RSTB(output->dev->lanes) | DPHY_C_RSTB,
               dsi->regs + MCTL_DPHY_CFG0);
}

static void cdns_dsi_init_link(struct cdns_dsi *dsi)
{
        struct cdns_dsi_output *output = &dsi->output;
        unsigned long sysclk_period, ulpout;
        u32 val;
        int i;

        if (dsi->link_initialized)
                return;

        val = 0;
        for (i = 1; i < output->dev->lanes; i++)
                val |= DATA_LANE_EN(i);

        if (!(output->dev->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS))
                val |= CLK_CONTINUOUS;

        writel(val, dsi->regs + MCTL_MAIN_PHY_CTL);

        /* ULPOUT should be set to 1ms and is expressed in sysclk cycles. */
        sysclk_period = NSEC_PER_SEC / clk_get_rate(dsi->dsi_sys_clk);
        ulpout = DIV_ROUND_UP(NSEC_PER_MSEC, sysclk_period);
        writel(CLK_LANE_ULPOUT_TIME(ulpout) | DATA_LANE_ULPOUT_TIME(ulpout),
               dsi->regs + MCTL_ULPOUT_TIME);

        writel(LINK_EN, dsi->regs + MCTL_MAIN_DATA_CTL);

        val = CLK_LANE_EN | PLL_START;
        for (i = 0; i < output->dev->lanes; i++)
                val |= DATA_LANE_START(i);

        writel(val, dsi->regs + MCTL_MAIN_EN);

        dsi->link_initialized = true;
}

static void cdns_dsi_bridge_enable(struct drm_bridge *bridge)
{
        struct cdns_dsi_input *input = bridge_to_cdns_dsi_input(bridge);
        struct cdns_dsi *dsi = input_to_dsi(input);
        struct cdns_dsi_output *output = &dsi->output;
        struct drm_display_mode *mode;
        struct phy_configure_opts_mipi_dphy *phy_cfg = &output->phy_opts.mipi_dphy;
        unsigned long tx_byte_period;
        struct cdns_dsi_cfg dsi_cfg;
        u32 tmp, reg_wakeup, div;
        int nlanes;

        if (WARN_ON(pm_runtime_get_sync(dsi->base.dev) < 0))
                return;

        mode = &bridge->encoder->crtc->state->adjusted_mode;
        nlanes = output->dev->lanes;

        WARN_ON_ONCE(cdns_dsi_check_conf(dsi, mode, &dsi_cfg, false));

        cdns_dsi_hs_init(dsi);
        cdns_dsi_init_link(dsi);

        writel(HBP_LEN(dsi_cfg.hbp) | HSA_LEN(dsi_cfg.hsa),
               dsi->regs + VID_HSIZE1);
        writel(HFP_LEN(dsi_cfg.hfp) | HACT_LEN(dsi_cfg.hact),
               dsi->regs + VID_HSIZE2);

        writel(VBP_LEN(mode->crtc_vtotal - mode->crtc_vsync_end - 1) |
               VFP_LEN(mode->crtc_vsync_start - mode->crtc_vdisplay) |
               VSA_LEN(mode->crtc_vsync_end - mode->crtc_vsync_start + 1),
               dsi->regs + VID_VSIZE1);
        writel(mode->crtc_vdisplay, dsi->regs + VID_VSIZE2);

        tmp = dsi_cfg.htotal -
              (dsi_cfg.hsa + DSI_BLANKING_FRAME_OVERHEAD +
               DSI_HSA_FRAME_OVERHEAD);
        writel(BLK_LINE_PULSE_PKT_LEN(tmp), dsi->regs + VID_BLKSIZE2);
        if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
                writel(MAX_LINE_LIMIT(tmp - DSI_NULL_FRAME_OVERHEAD),
                       dsi->regs + VID_VCA_SETTING2);

        tmp = dsi_cfg.htotal -
              (DSI_HSS_VSS_VSE_FRAME_OVERHEAD + DSI_BLANKING_FRAME_OVERHEAD);
        writel(BLK_LINE_EVENT_PKT_LEN(tmp), dsi->regs + VID_BLKSIZE1);
        if (!(output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE))
                writel(MAX_LINE_LIMIT(tmp - DSI_NULL_FRAME_OVERHEAD),
                       dsi->regs + VID_VCA_SETTING2);

        tmp = DIV_ROUND_UP(dsi_cfg.htotal, nlanes) -
              DIV_ROUND_UP(dsi_cfg.hsa, nlanes);

        if (!(output->dev->mode_flags & MIPI_DSI_MODE_EOT_PACKET))
                tmp -= DIV_ROUND_UP(DSI_EOT_PKT_SIZE, nlanes);

        tx_byte_period = DIV_ROUND_DOWN_ULL((u64)NSEC_PER_SEC * 8,
                                            phy_cfg->hs_clk_rate);
        reg_wakeup = (phy_cfg->hs_prepare + phy_cfg->hs_zero) / tx_byte_period;
        writel(REG_WAKEUP_TIME(reg_wakeup) | REG_LINE_DURATION(tmp),
               dsi->regs + VID_DPHY_TIME);

        /*
         * HSTX and LPRX timeouts are both expressed in TX byte clk cycles and
         * both should be set to at least the time it takes to transmit a
         * frame.
         */
        tmp = NSEC_PER_SEC / drm_mode_vrefresh(mode);
        tmp /= tx_byte_period;

        for (div = 0; div <= CLK_DIV_MAX; div++) {
                if (tmp <= HSTX_TIMEOUT_MAX)
                        break;

                tmp >>= 1;
        }

        if (tmp > HSTX_TIMEOUT_MAX)
                tmp = HSTX_TIMEOUT_MAX;

        writel(CLK_DIV(div) | HSTX_TIMEOUT(tmp),
               dsi->regs + MCTL_DPHY_TIMEOUT1);

        writel(LPRX_TIMEOUT(tmp), dsi->regs + MCTL_DPHY_TIMEOUT2);

        if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO) {
                switch (output->dev->format) {
                case MIPI_DSI_FMT_RGB888:
                        tmp = VID_PIXEL_MODE_RGB888 |
                              VID_DATATYPE(MIPI_DSI_PACKED_PIXEL_STREAM_24);
                        break;

                case MIPI_DSI_FMT_RGB666:
                        tmp = VID_PIXEL_MODE_RGB666 |
                              VID_DATATYPE(MIPI_DSI_PIXEL_STREAM_3BYTE_18);
                        break;

                case MIPI_DSI_FMT_RGB666_PACKED:
                        tmp = VID_PIXEL_MODE_RGB666_PACKED |
                              VID_DATATYPE(MIPI_DSI_PACKED_PIXEL_STREAM_18);
                        break;

                case MIPI_DSI_FMT_RGB565:
                        tmp = VID_PIXEL_MODE_RGB565 |
                              VID_DATATYPE(MIPI_DSI_PACKED_PIXEL_STREAM_16);
                        break;

                default:
                        dev_err(dsi->base.dev, "Unsupported DSI format\n");
                        return;
                }

                if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
                        tmp |= SYNC_PULSE_ACTIVE | SYNC_PULSE_HORIZONTAL;

                tmp |= REG_BLKLINE_MODE(REG_BLK_MODE_BLANKING_PKT) |
                       REG_BLKEOL_MODE(REG_BLK_MODE_BLANKING_PKT) |
                       RECOVERY_MODE(RECOVERY_MODE_NEXT_HSYNC) |
                       VID_IGNORE_MISS_VSYNC;

                writel(tmp, dsi->regs + VID_MAIN_CTL);
        }

        tmp = readl(dsi->regs + MCTL_MAIN_DATA_CTL);
        tmp &= ~(IF_VID_SELECT_MASK | HOST_EOT_GEN | IF_VID_MODE);

        if (!(output->dev->mode_flags & MIPI_DSI_MODE_EOT_PACKET))
                tmp |= HOST_EOT_GEN;

        if (output->dev->mode_flags & MIPI_DSI_MODE_VIDEO)
                tmp |= IF_VID_MODE | IF_VID_SELECT(input->id) | VID_EN;

        writel(tmp, dsi->regs + MCTL_MAIN_DATA_CTL);

        tmp = readl(dsi->regs + MCTL_MAIN_EN) | IF_EN(input->id);
        writel(tmp, dsi->regs + MCTL_MAIN_EN);
}

static const struct drm_bridge_funcs cdns_dsi_bridge_funcs = {
        .attach = cdns_dsi_bridge_attach,
        .mode_valid = cdns_dsi_bridge_mode_valid,
        .disable = cdns_dsi_bridge_disable,
        .enable = cdns_dsi_bridge_enable,
};

static int cdns_dsi_attach(struct mipi_dsi_host *host,
                           struct mipi_dsi_device *dev)
{
        struct cdns_dsi *dsi = to_cdns_dsi(host);
        struct cdns_dsi_output *output = &dsi->output;
        struct cdns_dsi_input *input = &dsi->input;
        struct drm_bridge *bridge;
        struct drm_panel *panel;
        struct device_node *np;
        int ret;

        /*
         * We currently do not support connecting several DSI devices to the
         * same host. In order to support that we'd need the DRM bridge
         * framework to allow dynamic reconfiguration of the bridge chain.
         */
        if (output->dev)
                return -EBUSY;

        /* We do not support burst mode yet. */
        if (dev->mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
                return -ENOTSUPP;

        /*
         * The host <-> device link might be described using an OF-graph
         * representation, in this case we extract the device of_node from
         * this representation, otherwise we use dsidev->dev.of_node which
         * should have been filled by the core.
         */
        np = of_graph_get_remote_node(dsi->base.dev->of_node, DSI_OUTPUT_PORT,
                                      dev->channel);
        if (!np)
                np = of_node_get(dev->dev.of_node);

        panel = of_drm_find_panel(np);
        if (!IS_ERR(panel)) {
                bridge = drm_panel_bridge_add_typed(panel,
                                                    DRM_MODE_CONNECTOR_DSI);
        } else {
                bridge = of_drm_find_bridge(dev->dev.of_node);
                if (!bridge)
                        bridge = ERR_PTR(-EINVAL);
        }

        of_node_put(np);

        if (IS_ERR(bridge)) {
                ret = PTR_ERR(bridge);
                dev_err(host->dev, "failed to add DSI device %s (err = %d)",
                        dev->name, ret);
                return ret;
        }

        output->dev = dev;
        output->bridge = bridge;
        output->panel = panel;

        /*
         * The DSI output has been properly configured, we can now safely
         * register the input to the bridge framework so that it can take place
         * in a display pipeline.
         */
        drm_bridge_add(&input->bridge);

        return 0;
}

static int cdns_dsi_detach(struct mipi_dsi_host *host,
                           struct mipi_dsi_device *dev)
{
        struct cdns_dsi *dsi = to_cdns_dsi(host);
        struct cdns_dsi_output *output = &dsi->output;
        struct cdns_dsi_input *input = &dsi->input;

        drm_bridge_remove(&input->bridge);
        if (output->panel)
                drm_panel_bridge_remove(output->bridge);

        return 0;
}

static irqreturn_t cdns_dsi_interrupt(int irq, void *data)
{
        struct cdns_dsi *dsi = data;
        irqreturn_t ret = IRQ_NONE;
        u32 flag, ctl;

        flag = readl(dsi->regs + DIRECT_CMD_STS_FLAG);
        if (flag) {
                ctl = readl(dsi->regs + DIRECT_CMD_STS_CTL);
                ctl &= ~flag;
                writel(ctl, dsi->regs + DIRECT_CMD_STS_CTL);
                complete(&dsi->direct_cmd_comp);
                ret = IRQ_HANDLED;
        }

        return ret;
}

static ssize_t cdns_dsi_transfer(struct mipi_dsi_host *host,
                                 const struct mipi_dsi_msg *msg)
{
        struct cdns_dsi *dsi = to_cdns_dsi(host);
        u32 cmd, sts, val, wait = WRITE_COMPLETED, ctl = 0;
        struct mipi_dsi_packet packet;
        int ret, i, tx_len, rx_len;

        ret = pm_runtime_get_sync(host->dev);
        if (ret < 0)
                return ret;

        cdns_dsi_init_link(dsi);

        ret = mipi_dsi_create_packet(&packet, msg);
        if (ret)
                goto out;

        tx_len = msg->tx_buf ? msg->tx_len : 0;
        rx_len = msg->rx_buf ? msg->rx_len : 0;

        /* For read operations, the maximum TX len is 2. */
        if (rx_len && tx_len > 2) {
                ret = -ENOTSUPP;
                goto out;
        }

        /* TX len is limited by the CMD FIFO depth. */
        if (tx_len > dsi->direct_cmd_fifo_depth) {
                ret = -ENOTSUPP;
                goto out;
        }

        /* RX len is limited by the RX FIFO depth. */
        if (rx_len > dsi->rx_fifo_depth) {
                ret = -ENOTSUPP;
                goto out;
        }

        cmd = CMD_SIZE(tx_len) | CMD_VCHAN_ID(msg->channel) |
              CMD_DATATYPE(msg->type);

        if (msg->flags & MIPI_DSI_MSG_USE_LPM)
                cmd |= CMD_LP_EN;

        if (mipi_dsi_packet_format_is_long(msg->type))
                cmd |= CMD_LONG;

        if (rx_len) {
                cmd |= READ_CMD;
                wait = READ_COMPLETED_WITH_ERR | READ_COMPLETED;
                ctl = READ_EN | BTA_EN;
        } else if (msg->flags & MIPI_DSI_MSG_REQ_ACK) {
                cmd |= BTA_REQ;
                wait = ACK_WITH_ERR_RCVD | ACK_RCVD;
                ctl = BTA_EN;
        }

        writel(readl(dsi->regs + MCTL_MAIN_DATA_CTL) | ctl,
               dsi->regs + MCTL_MAIN_DATA_CTL);

        writel(cmd, dsi->regs + DIRECT_CMD_MAIN_SETTINGS);

        for (i = 0; i < tx_len; i += 4) {
                const u8 *buf = msg->tx_buf;
                int j;

                val = 0;
                for (j = 0; j < 4 && j + i < tx_len; j++)
                        val |= (u32)buf[i + j] << (8 * j);

                writel(val, dsi->regs + DIRECT_CMD_WRDATA);
        }

        /* Clear status flags before sending the command. */
        writel(wait, dsi->regs + DIRECT_CMD_STS_CLR);
        writel(wait, dsi->regs + DIRECT_CMD_STS_CTL);
        reinit_completion(&dsi->direct_cmd_comp);
        writel(0, dsi->regs + DIRECT_CMD_SEND);

        wait_for_completion_timeout(&dsi->direct_cmd_comp,
                                    msecs_to_jiffies(1000));

        sts = readl(dsi->regs + DIRECT_CMD_STS);
        writel(wait, dsi->regs + DIRECT_CMD_STS_CLR);
        writel(0, dsi->regs + DIRECT_CMD_STS_CTL);

        writel(readl(dsi->regs + MCTL_MAIN_DATA_CTL) & ~ctl,
               dsi->regs + MCTL_MAIN_DATA_CTL);

        /* We did not receive the events we were waiting for. */
        if (!(sts & wait)) {
                ret = -ETIMEDOUT;
                goto out;
        }

        /* 'READ' or 'WRITE with ACK' failed. */
        if (sts & (READ_COMPLETED_WITH_ERR | ACK_WITH_ERR_RCVD)) {
                ret = -EIO;
                goto out;
        }

        for (i = 0; i < rx_len; i += 4) {
                u8 *buf = msg->rx_buf;
                int j;

                val = readl(dsi->regs + DIRECT_CMD_RDDATA);
                for (j = 0; j < 4 && j + i < rx_len; j++)
                        buf[i + j] = val >> (8 * j);
        }

out:
        pm_runtime_put(host->dev);
        return ret;
}

static const struct mipi_dsi_host_ops cdns_dsi_ops = {
        .attach = cdns_dsi_attach,
        .detach = cdns_dsi_detach,
        .transfer = cdns_dsi_transfer,
};

static int __maybe_unused cdns_dsi_resume(struct device *dev)
{
        struct cdns_dsi *dsi = dev_get_drvdata(dev);

        reset_control_deassert(dsi->dsi_p_rst);
        clk_prepare_enable(dsi->dsi_p_clk);
        clk_prepare_enable(dsi->dsi_sys_clk);

        return 0;
}

static int __maybe_unused cdns_dsi_suspend(struct device *dev)
{
        struct cdns_dsi *dsi = dev_get_drvdata(dev);

        clk_disable_unprepare(dsi->dsi_sys_clk);
        clk_disable_unprepare(dsi->dsi_p_clk);
        reset_control_assert(dsi->dsi_p_rst);
        dsi->link_initialized = false;
        return 0;
}

static UNIVERSAL_DEV_PM_OPS(cdns_dsi_pm_ops, cdns_dsi_suspend, cdns_dsi_resume,
                            NULL);

static int cdns_dsi_drm_probe(struct platform_device *pdev)
{
        struct cdns_dsi *dsi;
        struct cdns_dsi_input *input;
        struct resource *res;
        int ret, irq;
        u32 val;

        dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
        if (!dsi)
                return -ENOMEM;

        platform_set_drvdata(pdev, dsi);

        input = &dsi->input;

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        dsi->regs = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(dsi->regs))
                return PTR_ERR(dsi->regs);

        dsi->dsi_p_clk = devm_clk_get(&pdev->dev, "dsi_p_clk");
        if (IS_ERR(dsi->dsi_p_clk))
                return PTR_ERR(dsi->dsi_p_clk);

        dsi->dsi_p_rst = devm_reset_control_get_optional_exclusive(&pdev->dev,
                                                                "dsi_p_rst");
        if (IS_ERR(dsi->dsi_p_rst))
                return PTR_ERR(dsi->dsi_p_rst);

        dsi->dsi_sys_clk = devm_clk_get(&pdev->dev, "dsi_sys_clk");
        if (IS_ERR(dsi->dsi_sys_clk))
                return PTR_ERR(dsi->dsi_sys_clk);

        irq = platform_get_irq(pdev, 0);
        if (irq < 0)
                return irq;

        dsi->dphy = devm_phy_get(&pdev->dev, "dphy");
        if (IS_ERR(dsi->dphy))
                return PTR_ERR(dsi->dphy);

        ret = clk_prepare_enable(dsi->dsi_p_clk);
        if (ret)
                return ret;

        val = readl(dsi->regs + ID_REG);
        if (REV_VENDOR_ID(val) != 0xcad) {
                dev_err(&pdev->dev, "invalid vendor id\n");
                ret = -EINVAL;
                goto err_disable_pclk;
        }

        val = readl(dsi->regs + IP_CONF);
        dsi->direct_cmd_fifo_depth = 1 << (DIRCMD_FIFO_DEPTH(val) + 2);
        dsi->rx_fifo_depth = RX_FIFO_DEPTH(val);
        init_completion(&dsi->direct_cmd_comp);

        writel(0, dsi->regs + MCTL_MAIN_DATA_CTL);
        writel(0, dsi->regs + MCTL_MAIN_EN);
        writel(0, dsi->regs + MCTL_MAIN_PHY_CTL);

        /*
         * We only support the DPI input, so force input->id to
         * CDNS_DPI_INPUT.
         */
        input->id = CDNS_DPI_INPUT;
        input->bridge.funcs = &cdns_dsi_bridge_funcs;
        input->bridge.of_node = pdev->dev.of_node;

        /* Mask all interrupts before registering the IRQ handler. */
        writel(0, dsi->regs + MCTL_MAIN_STS_CTL);
        writel(0, dsi->regs + MCTL_DPHY_ERR_CTL1);
        writel(0, dsi->regs + CMD_MODE_STS_CTL);
        writel(0, dsi->regs + DIRECT_CMD_STS_CTL);
        writel(0, dsi->regs + DIRECT_CMD_RD_STS_CTL);
        writel(0, dsi->regs + VID_MODE_STS_CTL);
        writel(0, dsi->regs + TVG_STS_CTL);
        writel(0, dsi->regs + DPI_IRQ_EN);
        ret = devm_request_irq(&pdev->dev, irq, cdns_dsi_interrupt, 0,
                               dev_name(&pdev->dev), dsi);
        if (ret)
                goto err_disable_pclk;

        pm_runtime_enable(&pdev->dev);
        dsi->base.dev = &pdev->dev;
        dsi->base.ops = &cdns_dsi_ops;

        ret = mipi_dsi_host_register(&dsi->base);
        if (ret)
                goto err_disable_runtime_pm;

        clk_disable_unprepare(dsi->dsi_p_clk);

        return 0;

err_disable_runtime_pm:
        pm_runtime_disable(&pdev->dev);

err_disable_pclk:
        clk_disable_unprepare(dsi->dsi_p_clk);

        return ret;
}

static int cdns_dsi_drm_remove(struct platform_device *pdev)
{
        struct cdns_dsi *dsi = platform_get_drvdata(pdev);

        mipi_dsi_host_unregister(&dsi->base);
        pm_runtime_disable(&pdev->dev);

        return 0;
}

static const struct of_device_id cdns_dsi_of_match[] = {
        { .compatible = "cdns,dsi" },
        { },
};

static struct platform_driver cdns_dsi_platform_driver = {
        .probe  = cdns_dsi_drm_probe,
        .remove = cdns_dsi_drm_remove,
        .driver = {
                .name   = "cdns-dsi",
                .of_match_table = cdns_dsi_of_match,
                .pm = &cdns_dsi_pm_ops,
        },
};
module_platform_driver(cdns_dsi_platform_driver);

MODULE_AUTHOR("Boris Brezillon <boris.brezillon@bootlin.com>");
MODULE_DESCRIPTION("Cadence DSI driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:cdns-dsi");