[PATCH v2 01/12] drm: bridge: Add Samsung DSIM bridge driver

Marek Szyprowski m.szyprowski at samsung.com
Wed May 11 05:21:32 PDT 2022


On 04.05.2022 13:40, Jagan Teki wrote:
> Samsung MIPI DSIM controller is common DSI IP that can be used in various
> SoCs like Exynos, i.MX8M Mini/Nano.
>
> In order to access this DSI controller between various platform SoCs,
> the ideal way to incorporate this in the drm stack is via the drm bridge
> driver.
>
> This patch is trying to differentiate platform-specific and bridge driver
> code and keep maintaining the exynos_drm_dsi.c code as platform-specific
> glue code and samsung-dsim.c as a common bridge driver code.
>
> - Exynos specific glue code is exynos specific te_irq, host_attach, and
>    detach code along with conventional component_ops.
>
> - Samsung DSIM is a bridge driver which is common across all platforms and
>    the respective platform-specific glue will initialize at the end of the
>    probe. The platform-specific operations and other glue calls will invoke
>    on associate code areas.
>
> v2:
> * fixed exynos dsi driver conversion (Marek Szyprowski)
> * updated commit message
> * updated MAINTAINERS file
>
> v1:
> * Don't maintain component_ops in bridge driver
> * Don't maintain platform glue code in bridge driver
> * Add platform-specific glue code and make a common bridge
>
> Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
> Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
> ---
>   MAINTAINERS                             |    8 +
>   drivers/gpu/drm/bridge/Kconfig          |   12 +
>   drivers/gpu/drm/bridge/Makefile         |    1 +
>   drivers/gpu/drm/bridge/samsung-dsim.c   | 1687 ++++++++++++++++++++++
>   drivers/gpu/drm/exynos/Kconfig          |    1 +
>   drivers/gpu/drm/exynos/exynos_drm_dsi.c | 1724 +----------------------
>   include/drm/bridge/samsung-dsim.h       |   97 ++
>   7 files changed, 1869 insertions(+), 1661 deletions(-)
>   create mode 100644 drivers/gpu/drm/bridge/samsung-dsim.c
>   create mode 100644 include/drm/bridge/samsung-dsim.h
>
>
> diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c
> new file mode 100644
> index 000000000000..7745902f3f1e
> --- /dev/null
> +++ b/drivers/gpu/drm/bridge/samsung-dsim.c
> @@ -0,0 +1,1687 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Samsung MIPI DSIM bridge driver.
> + *
> + * Copyright (C) 2021 Amarula Solutions(India)
> + * Copyright (c) 2014 Samsung Electronics Co., Ltd
> + * Author: Jagan Teki <jagan at amarulasolutions.com>
> + *
> + * Based on exynos_drm_dsi from
> + * Tomasz Figa <t.figa at samsung.com>
> + */
> +
> +#include <asm/unaligned.h>
> +
> +#include <drm/bridge/samsung-dsim.h>
> +#include <drm/drm_panel.h>
> +#include <drm/drm_print.h>
> +
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/irq.h>
> +#include <linux/of_device.h>
> +#include <linux/phy/phy.h>
> +#include <linux/regulator/consumer.h>
> +
> +#include <video/mipi_display.h>
> +
> +/* returns true iff both arguments logically differs */
> +#define NEQV(a, b) (!(a) ^ !(b))
> +
> +/* DSIM_STATUS */
> +#define DSIM_STOP_STATE_DAT(x)		(((x) & 0xf) << 0)
> +#define DSIM_STOP_STATE_CLK		(1 << 8)
> +#define DSIM_TX_READY_HS_CLK		(1 << 10)
> +#define DSIM_PLL_STABLE			(1 << 31)
> +
> +/* DSIM_SWRST */
> +#define DSIM_FUNCRST			(1 << 16)
> +#define DSIM_SWRST			(1 << 0)
> +
> +/* DSIM_TIMEOUT */
> +#define DSIM_LPDR_TIMEOUT(x)		((x) << 0)
> +#define DSIM_BTA_TIMEOUT(x)		((x) << 16)
> +
> +/* DSIM_CLKCTRL */
> +#define DSIM_ESC_PRESCALER(x)		(((x) & 0xffff) << 0)
> +#define DSIM_ESC_PRESCALER_MASK		(0xffff << 0)
> +#define DSIM_LANE_ESC_CLK_EN_CLK	(1 << 19)
> +#define DSIM_LANE_ESC_CLK_EN_DATA(x)	(((x) & 0xf) << 20)
> +#define DSIM_LANE_ESC_CLK_EN_DATA_MASK	(0xf << 20)
> +#define DSIM_BYTE_CLKEN			(1 << 24)
> +#define DSIM_BYTE_CLK_SRC(x)		(((x) & 0x3) << 25)
> +#define DSIM_BYTE_CLK_SRC_MASK		(0x3 << 25)
> +#define DSIM_PLL_BYPASS			(1 << 27)
> +#define DSIM_ESC_CLKEN			(1 << 28)
> +#define DSIM_TX_REQUEST_HSCLK		(1 << 31)
> +
> +/* DSIM_CONFIG */
> +#define DSIM_LANE_EN_CLK		(1 << 0)
> +#define DSIM_LANE_EN(x)			(((x) & 0xf) << 1)
> +#define DSIM_NUM_OF_DATA_LANE(x)	(((x) & 0x3) << 5)
> +#define DSIM_SUB_PIX_FORMAT(x)		(((x) & 0x7) << 8)
> +#define DSIM_MAIN_PIX_FORMAT_MASK	(0x7 << 12)
> +#define DSIM_MAIN_PIX_FORMAT_RGB888	(0x7 << 12)
> +#define DSIM_MAIN_PIX_FORMAT_RGB666	(0x6 << 12)
> +#define DSIM_MAIN_PIX_FORMAT_RGB666_P	(0x5 << 12)
> +#define DSIM_MAIN_PIX_FORMAT_RGB565	(0x4 << 12)
> +#define DSIM_SUB_VC			(((x) & 0x3) << 16)
> +#define DSIM_MAIN_VC			(((x) & 0x3) << 18)
> +#define DSIM_HSA_MODE			(1 << 20)
> +#define DSIM_HBP_MODE			(1 << 21)
> +#define DSIM_HFP_MODE			(1 << 22)
> +#define DSIM_HSE_MODE			(1 << 23)
> +#define DSIM_AUTO_MODE			(1 << 24)
> +#define DSIM_VIDEO_MODE			(1 << 25)
> +#define DSIM_BURST_MODE			(1 << 26)
> +#define DSIM_SYNC_INFORM		(1 << 27)
> +#define DSIM_EOT_DISABLE		(1 << 28)
> +#define DSIM_MFLUSH_VS			(1 << 29)
> +/* This flag is valid only for exynos3250/3472/5260/5430 */
> +#define DSIM_CLKLANE_STOP		(1 << 30)
> +
> +/* DSIM_ESCMODE */
> +#define DSIM_TX_TRIGGER_RST		(1 << 4)
> +#define DSIM_TX_LPDT_LP			(1 << 6)
> +#define DSIM_CMD_LPDT_LP		(1 << 7)
> +#define DSIM_FORCE_BTA			(1 << 16)
> +#define DSIM_FORCE_STOP_STATE		(1 << 20)
> +#define DSIM_STOP_STATE_CNT(x)		(((x) & 0x7ff) << 21)
> +#define DSIM_STOP_STATE_CNT_MASK	(0x7ff << 21)
> +
> +/* DSIM_MDRESOL */
> +#define DSIM_MAIN_STAND_BY		(1 << 31)
> +#define DSIM_MAIN_VRESOL(x, num_bits)	(((x) & ((1 << (num_bits)) - 1)) << 16)
> +#define DSIM_MAIN_HRESOL(x, num_bits)	(((x) & ((1 << (num_bits)) - 1)) << 0)
> +
> +/* DSIM_MVPORCH */
> +#define DSIM_CMD_ALLOW(x)		((x) << 28)
> +#define DSIM_STABLE_VFP(x)		((x) << 16)
> +#define DSIM_MAIN_VBP(x)		((x) << 0)
> +#define DSIM_CMD_ALLOW_MASK		(0xf << 28)
> +#define DSIM_STABLE_VFP_MASK		(0x7ff << 16)
> +#define DSIM_MAIN_VBP_MASK		(0x7ff << 0)
> +
> +/* DSIM_MHPORCH */
> +#define DSIM_MAIN_HFP(x)		((x) << 16)
> +#define DSIM_MAIN_HBP(x)		((x) << 0)
> +#define DSIM_MAIN_HFP_MASK		((0xffff) << 16)
> +#define DSIM_MAIN_HBP_MASK		((0xffff) << 0)
> +
> +/* DSIM_MSYNC */
> +#define DSIM_MAIN_VSA(x)		((x) << 22)
> +#define DSIM_MAIN_HSA(x)		((x) << 0)
> +#define DSIM_MAIN_VSA_MASK		((0x3ff) << 22)
> +#define DSIM_MAIN_HSA_MASK		((0xffff) << 0)
> +
> +/* DSIM_SDRESOL */
> +#define DSIM_SUB_STANDY(x)		((x) << 31)
> +#define DSIM_SUB_VRESOL(x)		((x) << 16)
> +#define DSIM_SUB_HRESOL(x)		((x) << 0)
> +#define DSIM_SUB_STANDY_MASK		((0x1) << 31)
> +#define DSIM_SUB_VRESOL_MASK		((0x7ff) << 16)
> +#define DSIM_SUB_HRESOL_MASK		((0x7ff) << 0)
> +
> +/* DSIM_INTSRC */
> +#define DSIM_INT_PLL_STABLE		(1 << 31)
> +#define DSIM_INT_SW_RST_RELEASE		(1 << 30)
> +#define DSIM_INT_SFR_FIFO_EMPTY		(1 << 29)
> +#define DSIM_INT_SFR_HDR_FIFO_EMPTY	(1 << 28)
> +#define DSIM_INT_BTA			(1 << 25)
> +#define DSIM_INT_FRAME_DONE		(1 << 24)
> +#define DSIM_INT_RX_TIMEOUT		(1 << 21)
> +#define DSIM_INT_BTA_TIMEOUT		(1 << 20)
> +#define DSIM_INT_RX_DONE		(1 << 18)
> +#define DSIM_INT_RX_TE			(1 << 17)
> +#define DSIM_INT_RX_ACK			(1 << 16)
> +#define DSIM_INT_RX_ECC_ERR		(1 << 15)
> +#define DSIM_INT_RX_CRC_ERR		(1 << 14)
> +
> +/* DSIM_FIFOCTRL */
> +#define DSIM_RX_DATA_FULL		(1 << 25)
> +#define DSIM_RX_DATA_EMPTY		(1 << 24)
> +#define DSIM_SFR_HEADER_FULL		(1 << 23)
> +#define DSIM_SFR_HEADER_EMPTY		(1 << 22)
> +#define DSIM_SFR_PAYLOAD_FULL		(1 << 21)
> +#define DSIM_SFR_PAYLOAD_EMPTY		(1 << 20)
> +#define DSIM_I80_HEADER_FULL		(1 << 19)
> +#define DSIM_I80_HEADER_EMPTY		(1 << 18)
> +#define DSIM_I80_PAYLOAD_FULL		(1 << 17)
> +#define DSIM_I80_PAYLOAD_EMPTY		(1 << 16)
> +#define DSIM_SD_HEADER_FULL		(1 << 15)
> +#define DSIM_SD_HEADER_EMPTY		(1 << 14)
> +#define DSIM_SD_PAYLOAD_FULL		(1 << 13)
> +#define DSIM_SD_PAYLOAD_EMPTY		(1 << 12)
> +#define DSIM_MD_HEADER_FULL		(1 << 11)
> +#define DSIM_MD_HEADER_EMPTY		(1 << 10)
> +#define DSIM_MD_PAYLOAD_FULL		(1 << 9)
> +#define DSIM_MD_PAYLOAD_EMPTY		(1 << 8)
> +#define DSIM_RX_FIFO			(1 << 4)
> +#define DSIM_SFR_FIFO			(1 << 3)
> +#define DSIM_I80_FIFO			(1 << 2)
> +#define DSIM_SD_FIFO			(1 << 1)
> +#define DSIM_MD_FIFO			(1 << 0)
> +
> +/* DSIM_PHYACCHR */
> +#define DSIM_AFC_EN			(1 << 14)
> +#define DSIM_AFC_CTL(x)			(((x) & 0x7) << 5)
> +
> +/* DSIM_PLLCTRL */
> +#define DSIM_FREQ_BAND(x)		((x) << 24)
> +#define DSIM_PLL_EN			(1 << 23)
> +#define DSIM_PLL_P(x)			((x) << 13)
> +#define DSIM_PLL_M(x)			((x) << 4)
> +#define DSIM_PLL_S(x)			((x) << 1)
> +
> +/* DSIM_PHYCTRL */
> +#define DSIM_PHYCTRL_ULPS_EXIT(x)	(((x) & 0x1ff) << 0)
> +#define DSIM_PHYCTRL_B_DPHYCTL_VREG_LP	(1 << 30)
> +#define DSIM_PHYCTRL_B_DPHYCTL_SLEW_UP	(1 << 14)
> +
> +/* DSIM_PHYTIMING */
> +#define DSIM_PHYTIMING_LPX(x)		((x) << 8)
> +#define DSIM_PHYTIMING_HS_EXIT(x)	((x) << 0)
> +
> +/* DSIM_PHYTIMING1 */
> +#define DSIM_PHYTIMING1_CLK_PREPARE(x)	((x) << 24)
> +#define DSIM_PHYTIMING1_CLK_ZERO(x)	((x) << 16)
> +#define DSIM_PHYTIMING1_CLK_POST(x)	((x) << 8)
> +#define DSIM_PHYTIMING1_CLK_TRAIL(x)	((x) << 0)
> +
> +/* DSIM_PHYTIMING2 */
> +#define DSIM_PHYTIMING2_HS_PREPARE(x)	((x) << 16)
> +#define DSIM_PHYTIMING2_HS_ZERO(x)	((x) << 8)
> +#define DSIM_PHYTIMING2_HS_TRAIL(x)	((x) << 0)
> +
> +#define DSI_MAX_BUS_WIDTH		4
> +#define DSI_NUM_VIRTUAL_CHANNELS	4
> +#define DSI_TX_FIFO_SIZE		2048
> +#define DSI_RX_FIFO_SIZE		256
> +#define DSI_XFER_TIMEOUT_MS		100
> +#define DSI_RX_FIFO_EMPTY		0x30800002
> +
> +#define OLD_SCLK_MIPI_CLK_NAME		"pll_clk"
> +
> +static const char *const clk_names[5] = {
> +	"bus_clk",
> +	"sclk_mipi",
> +	"phyclk_mipidphy0_bitclkdiv8",
> +	"phyclk_mipidphy0_rxclkesc0",
> +	"sclk_rgb_vclk_to_dsim0"
> +};
> +
> +enum samsung_dsim_transfer_type {
> +	EXYNOS_DSI_TX,
> +	EXYNOS_DSI_RX,
> +};
> +
> +enum reg_idx {
> +	DSIM_STATUS_REG,	/* Status register */
> +	DSIM_SWRST_REG,		/* Software reset register */
> +	DSIM_CLKCTRL_REG,	/* Clock control register */
> +	DSIM_TIMEOUT_REG,	/* Time out register */
> +	DSIM_CONFIG_REG,	/* Configuration register */
> +	DSIM_ESCMODE_REG,	/* Escape mode register */
> +	DSIM_MDRESOL_REG,
> +	DSIM_MVPORCH_REG,	/* Main display Vporch register */
> +	DSIM_MHPORCH_REG,	/* Main display Hporch register */
> +	DSIM_MSYNC_REG,		/* Main display sync area register */
> +	DSIM_INTSRC_REG,	/* Interrupt source register */
> +	DSIM_INTMSK_REG,	/* Interrupt mask register */
> +	DSIM_PKTHDR_REG,	/* Packet Header FIFO register */
> +	DSIM_PAYLOAD_REG,	/* Payload FIFO register */
> +	DSIM_RXFIFO_REG,	/* Read FIFO register */
> +	DSIM_FIFOCTRL_REG,	/* FIFO status and control register */
> +	DSIM_PLLCTRL_REG,	/* PLL control register */
> +	DSIM_PHYCTRL_REG,
> +	DSIM_PHYTIMING_REG,
> +	DSIM_PHYTIMING1_REG,
> +	DSIM_PHYTIMING2_REG,
> +	NUM_REGS
> +};
> +
> +static const unsigned int exynos_reg_ofs[] = {
> +	[DSIM_STATUS_REG] =  0x00,
> +	[DSIM_SWRST_REG] =  0x04,
> +	[DSIM_CLKCTRL_REG] =  0x08,
> +	[DSIM_TIMEOUT_REG] =  0x0c,
> +	[DSIM_CONFIG_REG] =  0x10,
> +	[DSIM_ESCMODE_REG] =  0x14,
> +	[DSIM_MDRESOL_REG] =  0x18,
> +	[DSIM_MVPORCH_REG] =  0x1c,
> +	[DSIM_MHPORCH_REG] =  0x20,
> +	[DSIM_MSYNC_REG] =  0x24,
> +	[DSIM_INTSRC_REG] =  0x2c,
> +	[DSIM_INTMSK_REG] =  0x30,
> +	[DSIM_PKTHDR_REG] =  0x34,
> +	[DSIM_PAYLOAD_REG] =  0x38,
> +	[DSIM_RXFIFO_REG] =  0x3c,
> +	[DSIM_FIFOCTRL_REG] =  0x44,
> +	[DSIM_PLLCTRL_REG] =  0x4c,
> +	[DSIM_PHYCTRL_REG] =  0x5c,
> +	[DSIM_PHYTIMING_REG] =  0x64,
> +	[DSIM_PHYTIMING1_REG] =  0x68,
> +	[DSIM_PHYTIMING2_REG] =  0x6c,
> +};
> +
> +static const unsigned int exynos5433_reg_ofs[] = {
> +	[DSIM_STATUS_REG] = 0x04,
> +	[DSIM_SWRST_REG] = 0x0C,
> +	[DSIM_CLKCTRL_REG] = 0x10,
> +	[DSIM_TIMEOUT_REG] = 0x14,
> +	[DSIM_CONFIG_REG] = 0x18,
> +	[DSIM_ESCMODE_REG] = 0x1C,
> +	[DSIM_MDRESOL_REG] = 0x20,
> +	[DSIM_MVPORCH_REG] = 0x24,
> +	[DSIM_MHPORCH_REG] = 0x28,
> +	[DSIM_MSYNC_REG] = 0x2C,
> +	[DSIM_INTSRC_REG] = 0x34,
> +	[DSIM_INTMSK_REG] = 0x38,
> +	[DSIM_PKTHDR_REG] = 0x3C,
> +	[DSIM_PAYLOAD_REG] = 0x40,
> +	[DSIM_RXFIFO_REG] = 0x44,
> +	[DSIM_FIFOCTRL_REG] = 0x4C,
> +	[DSIM_PLLCTRL_REG] = 0x94,
> +	[DSIM_PHYCTRL_REG] = 0xA4,
> +	[DSIM_PHYTIMING_REG] = 0xB4,
> +	[DSIM_PHYTIMING1_REG] = 0xB8,
> +	[DSIM_PHYTIMING2_REG] = 0xBC,
> +};
> +
> +enum reg_value_idx {
> +	RESET_TYPE,
> +	PLL_TIMER,
> +	STOP_STATE_CNT,
> +	PHYCTRL_ULPS_EXIT,
> +	PHYCTRL_VREG_LP,
> +	PHYCTRL_SLEW_UP,
> +	PHYTIMING_LPX,
> +	PHYTIMING_HS_EXIT,
> +	PHYTIMING_CLK_PREPARE,
> +	PHYTIMING_CLK_ZERO,
> +	PHYTIMING_CLK_POST,
> +	PHYTIMING_CLK_TRAIL,
> +	PHYTIMING_HS_PREPARE,
> +	PHYTIMING_HS_ZERO,
> +	PHYTIMING_HS_TRAIL
> +};
> +
> +static const unsigned int reg_values[] = {
> +	[RESET_TYPE] = DSIM_SWRST,
> +	[PLL_TIMER] = 500,
> +	[STOP_STATE_CNT] = 0xf,
> +	[PHYCTRL_ULPS_EXIT] = DSIM_PHYCTRL_ULPS_EXIT(0x0af),
> +	[PHYCTRL_VREG_LP] = 0,
> +	[PHYCTRL_SLEW_UP] = 0,
> +	[PHYTIMING_LPX] = DSIM_PHYTIMING_LPX(0x06),
> +	[PHYTIMING_HS_EXIT] = DSIM_PHYTIMING_HS_EXIT(0x0b),
> +	[PHYTIMING_CLK_PREPARE] = DSIM_PHYTIMING1_CLK_PREPARE(0x07),
> +	[PHYTIMING_CLK_ZERO] = DSIM_PHYTIMING1_CLK_ZERO(0x27),
> +	[PHYTIMING_CLK_POST] = DSIM_PHYTIMING1_CLK_POST(0x0d),
> +	[PHYTIMING_CLK_TRAIL] = DSIM_PHYTIMING1_CLK_TRAIL(0x08),
> +	[PHYTIMING_HS_PREPARE] = DSIM_PHYTIMING2_HS_PREPARE(0x09),
> +	[PHYTIMING_HS_ZERO] = DSIM_PHYTIMING2_HS_ZERO(0x0d),
> +	[PHYTIMING_HS_TRAIL] = DSIM_PHYTIMING2_HS_TRAIL(0x0b),
> +};
> +
> +static const unsigned int exynos5422_reg_values[] = {
> +	[RESET_TYPE] = DSIM_SWRST,
> +	[PLL_TIMER] = 500,
> +	[STOP_STATE_CNT] = 0xf,
> +	[PHYCTRL_ULPS_EXIT] = DSIM_PHYCTRL_ULPS_EXIT(0xaf),
> +	[PHYCTRL_VREG_LP] = 0,
> +	[PHYCTRL_SLEW_UP] = 0,
> +	[PHYTIMING_LPX] = DSIM_PHYTIMING_LPX(0x08),
> +	[PHYTIMING_HS_EXIT] = DSIM_PHYTIMING_HS_EXIT(0x0d),
> +	[PHYTIMING_CLK_PREPARE] = DSIM_PHYTIMING1_CLK_PREPARE(0x09),
> +	[PHYTIMING_CLK_ZERO] = DSIM_PHYTIMING1_CLK_ZERO(0x30),
> +	[PHYTIMING_CLK_POST] = DSIM_PHYTIMING1_CLK_POST(0x0e),
> +	[PHYTIMING_CLK_TRAIL] = DSIM_PHYTIMING1_CLK_TRAIL(0x0a),
> +	[PHYTIMING_HS_PREPARE] = DSIM_PHYTIMING2_HS_PREPARE(0x0c),
> +	[PHYTIMING_HS_ZERO] = DSIM_PHYTIMING2_HS_ZERO(0x11),
> +	[PHYTIMING_HS_TRAIL] = DSIM_PHYTIMING2_HS_TRAIL(0x0d),
> +};
> +
> +static const unsigned int exynos5433_reg_values[] = {
> +	[RESET_TYPE] = DSIM_FUNCRST,
> +	[PLL_TIMER] = 22200,
> +	[STOP_STATE_CNT] = 0xa,
> +	[PHYCTRL_ULPS_EXIT] = DSIM_PHYCTRL_ULPS_EXIT(0x190),
> +	[PHYCTRL_VREG_LP] = DSIM_PHYCTRL_B_DPHYCTL_VREG_LP,
> +	[PHYCTRL_SLEW_UP] = DSIM_PHYCTRL_B_DPHYCTL_SLEW_UP,
> +	[PHYTIMING_LPX] = DSIM_PHYTIMING_LPX(0x07),
> +	[PHYTIMING_HS_EXIT] = DSIM_PHYTIMING_HS_EXIT(0x0c),
> +	[PHYTIMING_CLK_PREPARE] = DSIM_PHYTIMING1_CLK_PREPARE(0x09),
> +	[PHYTIMING_CLK_ZERO] = DSIM_PHYTIMING1_CLK_ZERO(0x2d),
> +	[PHYTIMING_CLK_POST] = DSIM_PHYTIMING1_CLK_POST(0x0e),
> +	[PHYTIMING_CLK_TRAIL] = DSIM_PHYTIMING1_CLK_TRAIL(0x09),
> +	[PHYTIMING_HS_PREPARE] = DSIM_PHYTIMING2_HS_PREPARE(0x0b),
> +	[PHYTIMING_HS_ZERO] = DSIM_PHYTIMING2_HS_ZERO(0x10),
> +	[PHYTIMING_HS_TRAIL] = DSIM_PHYTIMING2_HS_TRAIL(0x0c),
> +};
> +
> +static const struct samsung_dsim_driver_data exynos3_dsi_driver_data = {
> +	.reg_ofs = exynos_reg_ofs,
> +	.plltmr_reg = 0x50,
> +	.has_freqband = 1,
> +	.has_clklane_stop = 1,
> +	.num_clks = 2,
> +	.max_freq = 1000,
> +	.wait_for_reset = 1,
> +	.num_bits_resol = 11,
> +	.reg_values = reg_values,
> +};
> +
> +static const struct samsung_dsim_driver_data exynos4_dsi_driver_data = {
> +	.reg_ofs = exynos_reg_ofs,
> +	.plltmr_reg = 0x50,
> +	.has_freqband = 1,
> +	.has_clklane_stop = 1,
> +	.num_clks = 2,
> +	.max_freq = 1000,
> +	.wait_for_reset = 1,
> +	.num_bits_resol = 11,
> +	.reg_values = reg_values,
> +};
> +
> +static const struct samsung_dsim_driver_data exynos5_dsi_driver_data = {
> +	.reg_ofs = exynos_reg_ofs,
> +	.plltmr_reg = 0x58,
> +	.num_clks = 2,
> +	.max_freq = 1000,
> +	.wait_for_reset = 1,
> +	.num_bits_resol = 11,
> +	.reg_values = reg_values,
> +};
> +
> +static const struct samsung_dsim_driver_data exynos5433_dsi_driver_data = {
> +	.reg_ofs = exynos5433_reg_ofs,
> +	.plltmr_reg = 0xa0,
> +	.has_clklane_stop = 1,
> +	.num_clks = 5,
> +	.max_freq = 1500,
> +	.wait_for_reset = 0,
> +	.num_bits_resol = 12,
> +	.reg_values = exynos5433_reg_values,
> +};
> +
> +static const struct samsung_dsim_driver_data exynos5422_dsi_driver_data = {
> +	.reg_ofs = exynos5433_reg_ofs,
> +	.plltmr_reg = 0xa0,
> +	.has_clklane_stop = 1,
> +	.num_clks = 2,
> +	.max_freq = 1500,
> +	.wait_for_reset = 1,
> +	.num_bits_resol = 12,
> +	.reg_values = exynos5422_reg_values,
> +};
> +
> +static const struct of_device_id samsung_dsim_of_match[] = {
> +	{
> +		.compatible = "samsung,exynos3250-mipi-dsi",
> +		.data = &exynos3_dsi_driver_data
> +	},
> +	{
> +		.compatible = "samsung,exynos4210-mipi-dsi",
> +		.data = &exynos4_dsi_driver_data
> +	},
> +	{
> +		.compatible = "samsung,exynos5410-mipi-dsi",
> +		.data = &exynos5_dsi_driver_data
> +	},
> +	{
> +		.compatible = "samsung,exynos5422-mipi-dsi",
> +		.data = &exynos5422_dsi_driver_data
> +	},
> +	{
> +		.compatible = "samsung,exynos5433-mipi-dsi",
> +		.data = &exynos5433_dsi_driver_data
> +	},
> +	{ /* sentinel. */ }
> +};
> +
> +static inline struct samsung_dsim *host_to_dsi(struct mipi_dsi_host *h)
> +{
> +	return container_of(h, struct samsung_dsim, dsi_host);
> +}
> +
> +static inline struct samsung_dsim *bridge_to_dsi(struct drm_bridge *b)
> +{
> +	return container_of(b, struct samsung_dsim, bridge);
> +}
> +
> +static inline void samsung_dsim_write(struct samsung_dsim *dsi,
> +				      enum reg_idx idx, u32 val)
> +{
> +	writel(val, dsi->reg_base + dsi->driver_data->reg_ofs[idx]);
> +}
> +
> +static inline u32 samsung_dsim_read(struct samsung_dsim *dsi, enum reg_idx idx)
> +{
> +	return readl(dsi->reg_base + dsi->driver_data->reg_ofs[idx]);
> +}
> +
> +static void samsung_dsim_wait_for_reset(struct samsung_dsim *dsi)
> +{
> +	if (wait_for_completion_timeout(&dsi->completed, msecs_to_jiffies(300)))
> +		return;
> +
> +	dev_err(dsi->dev, "timeout waiting for reset\n");
> +}
> +
> +static void samsung_dsim_reset(struct samsung_dsim *dsi)
> +{
> +	u32 reset_val = dsi->driver_data->reg_values[RESET_TYPE];
> +
> +	reinit_completion(&dsi->completed);
> +	samsung_dsim_write(dsi, DSIM_SWRST_REG, reset_val);
> +}
> +
> +#ifndef MHZ
> +#define MHZ	(1000*1000)
> +#endif
> +
> +static unsigned long samsung_dsim_pll_find_pms(struct samsung_dsim *dsi,
> +					       unsigned long fin,
> +					       unsigned long fout,
> +					       u8 *p, u16 *m, u8 *s)
> +{
> +	const struct samsung_dsim_driver_data *driver_data = dsi->driver_data;
> +	unsigned long best_freq = 0;
> +	u32 min_delta = 0xffffffff;
> +	u8 p_min, p_max;
> +	u8 _p, best_p;
> +	u16 _m, best_m;
> +	u8 _s, best_s;
> +
> +	p_min = DIV_ROUND_UP(fin, (12 * MHZ));
> +	p_max = fin / (6 * MHZ);
> +
> +	for (_p = p_min; _p <= p_max; ++_p) {
> +		for (_s = 0; _s <= 5; ++_s) {
> +			u64 tmp;
> +			u32 delta;
> +
> +			tmp = (u64)fout * (_p << _s);
> +			do_div(tmp, fin);
> +			_m = tmp;
> +			if (_m < 41 || _m > 125)
> +				continue;
> +
> +			tmp = (u64)_m * fin;
> +			do_div(tmp, _p);
> +			if (tmp < 500 * MHZ ||
> +					tmp > driver_data->max_freq * MHZ)
> +				continue;
> +
> +			tmp = (u64)_m * fin;
> +			do_div(tmp, _p << _s);
> +
> +			delta = abs(fout - tmp);
> +			if (delta < min_delta) {
> +				best_p = _p;
> +				best_m = _m;
> +				best_s = _s;
> +				min_delta = delta;
> +				best_freq = tmp;
> +			}
> +		}
> +	}
> +
> +	if (best_freq) {
> +		*p = best_p;
> +		*m = best_m;
> +		*s = best_s;
> +	}
> +
> +	return best_freq;
> +}
> +
> +static unsigned long samsung_dsim_set_pll(struct samsung_dsim *dsi,
> +					  unsigned long freq)
> +{
> +	const struct samsung_dsim_driver_data *driver_data = dsi->driver_data;
> +	unsigned long fin, fout;
> +	int timeout;
> +	u8 p, s;
> +	u16 m;
> +	u32 reg;
> +
> +	fin = dsi->pll_clk_rate;
> +	fout = samsung_dsim_pll_find_pms(dsi, fin, freq, &p, &m, &s);
> +	if (!fout) {
> +		dev_err(dsi->dev,
> +			"failed to find PLL PMS for requested frequency\n");
> +		return 0;
> +	}
> +	dev_dbg(dsi->dev, "PLL freq %lu, (p %d, m %d, s %d)\n", fout, p, m, s);
> +
> +	writel(driver_data->reg_values[PLL_TIMER],
> +			dsi->reg_base + driver_data->plltmr_reg);
> +
> +	reg = DSIM_PLL_EN | DSIM_PLL_P(p) | DSIM_PLL_M(m) | DSIM_PLL_S(s);
> +
> +	if (driver_data->has_freqband) {
> +		static const unsigned long freq_bands[] = {
> +			100 * MHZ, 120 * MHZ, 160 * MHZ, 200 * MHZ,
> +			270 * MHZ, 320 * MHZ, 390 * MHZ, 450 * MHZ,
> +			510 * MHZ, 560 * MHZ, 640 * MHZ, 690 * MHZ,
> +			770 * MHZ, 870 * MHZ, 950 * MHZ,
> +		};
> +		int band;
> +
> +		for (band = 0; band < ARRAY_SIZE(freq_bands); ++band)
> +			if (fout < freq_bands[band])
> +				break;
> +
> +		dev_dbg(dsi->dev, "band %d\n", band);
> +
> +		reg |= DSIM_FREQ_BAND(band);
> +	}
> +
> +	samsung_dsim_write(dsi, DSIM_PLLCTRL_REG, reg);
> +
> +	timeout = 1000;
> +	do {
> +		if (timeout-- == 0) {
> +			dev_err(dsi->dev, "PLL failed to stabilize\n");
> +			return 0;
> +		}
> +		reg = samsung_dsim_read(dsi, DSIM_STATUS_REG);
> +	} while ((reg & DSIM_PLL_STABLE) == 0);
> +
> +	return fout;
> +}
> +
> +static int samsung_dsim_enable_clock(struct samsung_dsim *dsi)
> +{
> +	unsigned long hs_clk, byte_clk, esc_clk;
> +	unsigned long esc_div;
> +	u32 reg;
> +
> +	hs_clk = samsung_dsim_set_pll(dsi, dsi->burst_clk_rate);
> +	if (!hs_clk) {
> +		dev_err(dsi->dev, "failed to configure DSI PLL\n");
> +		return -EFAULT;
> +	}
> +
> +	byte_clk = hs_clk / 8;
> +	esc_div = DIV_ROUND_UP(byte_clk, dsi->esc_clk_rate);
> +	esc_clk = byte_clk / esc_div;
> +
> +	if (esc_clk > 20 * MHZ) {
> +		++esc_div;
> +		esc_clk = byte_clk / esc_div;
> +	}
> +
> +	dev_dbg(dsi->dev, "hs_clk = %lu, byte_clk = %lu, esc_clk = %lu\n",
> +		hs_clk, byte_clk, esc_clk);
> +
> +	reg = samsung_dsim_read(dsi, DSIM_CLKCTRL_REG);
> +	reg &= ~(DSIM_ESC_PRESCALER_MASK | DSIM_LANE_ESC_CLK_EN_CLK
> +			| DSIM_LANE_ESC_CLK_EN_DATA_MASK | DSIM_PLL_BYPASS
> +			| DSIM_BYTE_CLK_SRC_MASK);
> +	reg |= DSIM_ESC_CLKEN | DSIM_BYTE_CLKEN
> +			| DSIM_ESC_PRESCALER(esc_div)
> +			| DSIM_LANE_ESC_CLK_EN_CLK
> +			| DSIM_LANE_ESC_CLK_EN_DATA(BIT(dsi->lanes) - 1)
> +			| DSIM_BYTE_CLK_SRC(0)
> +			| DSIM_TX_REQUEST_HSCLK;
> +	samsung_dsim_write(dsi, DSIM_CLKCTRL_REG, reg);
> +
> +	return 0;
> +}
> +
> +static void samsung_dsim_set_phy_ctrl(struct samsung_dsim *dsi)
> +{
> +	const struct samsung_dsim_driver_data *driver_data = dsi->driver_data;
> +	const unsigned int *reg_values = driver_data->reg_values;
> +	u32 reg;
> +
> +	if (driver_data->has_freqband)
> +		return;
> +
> +	/* B D-PHY: D-PHY Master & Slave Analog Block control */
> +	reg = reg_values[PHYCTRL_ULPS_EXIT] | reg_values[PHYCTRL_VREG_LP] |
> +		reg_values[PHYCTRL_SLEW_UP];
> +	samsung_dsim_write(dsi, DSIM_PHYCTRL_REG, reg);
> +
> +	/*
> +	 * T LPX: Transmitted length of any Low-Power state period
> +	 * T HS-EXIT: Time that the transmitter drives LP-11 following a HS
> +	 *	burst
> +	 */
> +	reg = reg_values[PHYTIMING_LPX] | reg_values[PHYTIMING_HS_EXIT];
> +	samsung_dsim_write(dsi, DSIM_PHYTIMING_REG, reg);
> +
> +	/*
> +	 * T CLK-PREPARE: Time that the transmitter drives the Clock Lane LP-00
> +	 *	Line state immediately before the HS-0 Line state starting the
> +	 *	HS transmission
> +	 * T CLK-ZERO: Time that the transmitter drives the HS-0 state prior to
> +	 *	transmitting the Clock.
> +	 * T CLK_POST: Time that the transmitter continues to send HS clock
> +	 *	after the last associated Data Lane has transitioned to LP Mode
> +	 *	Interval is defined as the period from the end of T HS-TRAIL to
> +	 *	the beginning of T CLK-TRAIL
> +	 * T CLK-TRAIL: Time that the transmitter drives the HS-0 state after
> +	 *	the last payload clock bit of a HS transmission burst
> +	 */
> +	reg = reg_values[PHYTIMING_CLK_PREPARE] |
> +		reg_values[PHYTIMING_CLK_ZERO] |
> +		reg_values[PHYTIMING_CLK_POST] |
> +		reg_values[PHYTIMING_CLK_TRAIL];
> +
> +	samsung_dsim_write(dsi, DSIM_PHYTIMING1_REG, reg);
> +
> +	/*
> +	 * T HS-PREPARE: Time that the transmitter drives the Data Lane LP-00
> +	 *	Line state immediately before the HS-0 Line state starting the
> +	 *	HS transmission
> +	 * T HS-ZERO: Time that the transmitter drives the HS-0 state prior to
> +	 *	transmitting the Sync sequence.
> +	 * T HS-TRAIL: Time that the transmitter drives the flipped differential
> +	 *	state after last payload data bit of a HS transmission burst
> +	 */
> +	reg = reg_values[PHYTIMING_HS_PREPARE] | reg_values[PHYTIMING_HS_ZERO] |
> +		reg_values[PHYTIMING_HS_TRAIL];
> +	samsung_dsim_write(dsi, DSIM_PHYTIMING2_REG, reg);
> +}
> +
> +static void samsung_dsim_disable_clock(struct samsung_dsim *dsi)
> +{
> +	u32 reg;
> +
> +	reg = samsung_dsim_read(dsi, DSIM_CLKCTRL_REG);
> +	reg &= ~(DSIM_LANE_ESC_CLK_EN_CLK | DSIM_LANE_ESC_CLK_EN_DATA_MASK
> +			| DSIM_ESC_CLKEN | DSIM_BYTE_CLKEN);
> +	samsung_dsim_write(dsi, DSIM_CLKCTRL_REG, reg);
> +
> +	reg = samsung_dsim_read(dsi, DSIM_PLLCTRL_REG);
> +	reg &= ~DSIM_PLL_EN;
> +	samsung_dsim_write(dsi, DSIM_PLLCTRL_REG, reg);
> +}
> +
> +static void samsung_dsim_enable_lane(struct samsung_dsim *dsi, u32 lane)
> +{
> +	u32 reg = samsung_dsim_read(dsi, DSIM_CONFIG_REG);
> +
> +	reg |= (DSIM_NUM_OF_DATA_LANE(dsi->lanes - 1) | DSIM_LANE_EN_CLK |
> +			DSIM_LANE_EN(lane));
> +	samsung_dsim_write(dsi, DSIM_CONFIG_REG, reg);
> +}
> +
> +static int samsung_dsim_init_link(struct samsung_dsim *dsi)
> +{
> +	const struct samsung_dsim_driver_data *driver_data = dsi->driver_data;
> +	int timeout;
> +	u32 reg;
> +	u32 lanes_mask;
> +
> +	/* Initialize FIFO pointers */
> +	reg = samsung_dsim_read(dsi, DSIM_FIFOCTRL_REG);
> +	reg &= ~0x1f;
> +	samsung_dsim_write(dsi, DSIM_FIFOCTRL_REG, reg);
> +
> +	usleep_range(9000, 11000);
> +
> +	reg |= 0x1f;
> +	samsung_dsim_write(dsi, DSIM_FIFOCTRL_REG, reg);
> +	usleep_range(9000, 11000);
> +
> +	/* DSI configuration */
> +	reg = 0;
> +
> +	/*
> +	 * The first bit of mode_flags specifies display configuration.
> +	 * If this bit is set[= MIPI_DSI_MODE_VIDEO], dsi will support video
> +	 * mode, otherwise it will support command mode.
> +	 */
> +	if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
> +		reg |= DSIM_VIDEO_MODE;
> +
> +		/*
> +		 * The user manual describes that following bits are ignored in
> +		 * command mode.
> +		 */
> +		if (!(dsi->mode_flags & MIPI_DSI_MODE_VSYNC_FLUSH))
> +			reg |= DSIM_MFLUSH_VS;
> +		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
> +			reg |= DSIM_SYNC_INFORM;
> +		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
> +			reg |= DSIM_BURST_MODE;
> +		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_AUTO_VERT)
> +			reg |= DSIM_AUTO_MODE;
> +		if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_HSE)
> +			reg |= DSIM_HSE_MODE;
> +		if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HFP))
> +			reg |= DSIM_HFP_MODE;
> +		if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HBP))
> +			reg |= DSIM_HBP_MODE;
> +		if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_NO_HSA))
> +			reg |= DSIM_HSA_MODE;
> +	}
> +
> +	if (!(dsi->mode_flags & MIPI_DSI_MODE_NO_EOT_PACKET))
> +		reg |= DSIM_EOT_DISABLE;
> +
> +	switch (dsi->format) {
> +	case MIPI_DSI_FMT_RGB888:
> +		reg |= DSIM_MAIN_PIX_FORMAT_RGB888;
> +		break;
> +	case MIPI_DSI_FMT_RGB666:
> +		reg |= DSIM_MAIN_PIX_FORMAT_RGB666;
> +		break;
> +	case MIPI_DSI_FMT_RGB666_PACKED:
> +		reg |= DSIM_MAIN_PIX_FORMAT_RGB666_P;
> +		break;
> +	case MIPI_DSI_FMT_RGB565:
> +		reg |= DSIM_MAIN_PIX_FORMAT_RGB565;
> +		break;
> +	default:
> +		dev_err(dsi->dev, "invalid pixel format\n");
> +		return -EINVAL;
> +	}
> +
> +	/*
> +	 * Use non-continuous clock mode if the periparal wants and
> +	 * host controller supports
> +	 *
> +	 * In non-continous clock mode, host controller will turn off
> +	 * the HS clock between high-speed transmissions to reduce
> +	 * power consumption.
> +	 */
> +	if (driver_data->has_clklane_stop &&
> +			dsi->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) {
> +		reg |= DSIM_CLKLANE_STOP;
> +	}
> +	samsung_dsim_write(dsi, DSIM_CONFIG_REG, reg);
> +
> +	lanes_mask = BIT(dsi->lanes) - 1;
> +	samsung_dsim_enable_lane(dsi, lanes_mask);
> +
> +	/* Check clock and data lane state are stop state */
> +	timeout = 100;
> +	do {
> +		if (timeout-- == 0) {
> +			dev_err(dsi->dev, "waiting for bus lanes timed out\n");
> +			return -EFAULT;
> +		}
> +
> +		reg = samsung_dsim_read(dsi, DSIM_STATUS_REG);
> +		if ((reg & DSIM_STOP_STATE_DAT(lanes_mask))
> +		    != DSIM_STOP_STATE_DAT(lanes_mask))
> +			continue;
> +	} while (!(reg & (DSIM_STOP_STATE_CLK | DSIM_TX_READY_HS_CLK)));
> +
> +	reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
> +	reg &= ~DSIM_STOP_STATE_CNT_MASK;
> +	reg |= DSIM_STOP_STATE_CNT(driver_data->reg_values[STOP_STATE_CNT]);
> +	samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);
> +
> +	reg = DSIM_BTA_TIMEOUT(0xff) | DSIM_LPDR_TIMEOUT(0xffff);
> +	samsung_dsim_write(dsi, DSIM_TIMEOUT_REG, reg);
> +
> +	return 0;
> +}
> +
> +static void samsung_dsim_set_display_mode(struct samsung_dsim *dsi)
> +{
> +	struct drm_display_mode *m = &dsi->mode;
> +	unsigned int num_bits_resol = dsi->driver_data->num_bits_resol;
> +	u32 reg;
> +
> +	if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
> +		reg = DSIM_CMD_ALLOW(0xf)
> +			| DSIM_STABLE_VFP(m->vsync_start - m->vdisplay)
> +			| DSIM_MAIN_VBP(m->vtotal - m->vsync_end);
> +		samsung_dsim_write(dsi, DSIM_MVPORCH_REG, reg);
> +
> +		reg = DSIM_MAIN_HFP(m->hsync_start - m->hdisplay)
> +			| DSIM_MAIN_HBP(m->htotal - m->hsync_end);
> +		samsung_dsim_write(dsi, DSIM_MHPORCH_REG, reg);
> +
> +		reg = DSIM_MAIN_VSA(m->vsync_end - m->vsync_start)
> +			| DSIM_MAIN_HSA(m->hsync_end - m->hsync_start);
> +		samsung_dsim_write(dsi, DSIM_MSYNC_REG, reg);
> +	}
> +	reg =  DSIM_MAIN_HRESOL(m->hdisplay, num_bits_resol) |
> +		DSIM_MAIN_VRESOL(m->vdisplay, num_bits_resol);
> +
> +	samsung_dsim_write(dsi, DSIM_MDRESOL_REG, reg);
> +
> +	dev_dbg(dsi->dev, "LCD size = %dx%d\n", m->hdisplay, m->vdisplay);
> +}
> +
> +static void samsung_dsim_set_display_enable(struct samsung_dsim *dsi, bool enable)
> +{
> +	u32 reg;
> +
> +	reg = samsung_dsim_read(dsi, DSIM_MDRESOL_REG);
> +	if (enable)
> +		reg |= DSIM_MAIN_STAND_BY;
> +	else
> +		reg &= ~DSIM_MAIN_STAND_BY;
> +	samsung_dsim_write(dsi, DSIM_MDRESOL_REG, reg);
> +}
> +
> +static int samsung_dsim_wait_for_hdr_fifo(struct samsung_dsim *dsi)
> +{
> +	int timeout = 2000;
> +
> +	do {
> +		u32 reg = samsung_dsim_read(dsi, DSIM_FIFOCTRL_REG);
> +
> +		if (!(reg & DSIM_SFR_HEADER_FULL))
> +			return 0;
> +
> +		if (!cond_resched())
> +			usleep_range(950, 1050);
> +	} while (--timeout);
> +
> +	return -ETIMEDOUT;
> +}
> +
> +static void samsung_dsim_set_cmd_lpm(struct samsung_dsim *dsi, bool lpm)
> +{
> +	u32 v = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
> +
> +	if (lpm)
> +		v |= DSIM_CMD_LPDT_LP;
> +	else
> +		v &= ~DSIM_CMD_LPDT_LP;
> +
> +	samsung_dsim_write(dsi, DSIM_ESCMODE_REG, v);
> +}
> +
> +static void samsung_dsim_force_bta(struct samsung_dsim *dsi)
> +{
> +	u32 v = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
> +
> +	v |= DSIM_FORCE_BTA;
> +	samsung_dsim_write(dsi, DSIM_ESCMODE_REG, v);
> +}
> +
> +static void samsung_dsim_send_to_fifo(struct samsung_dsim *dsi,
> +				      struct samsung_dsim_transfer *xfer)
> +{
> +	struct device *dev = dsi->dev;
> +	struct mipi_dsi_packet *pkt = &xfer->packet;
> +	const u8 *payload = pkt->payload + xfer->tx_done;
> +	u16 length = pkt->payload_length - xfer->tx_done;
> +	bool first = !xfer->tx_done;
> +	u32 reg;
> +
> +	dev_dbg(dev, "< xfer %pK: tx len %u, done %u, rx len %u, done %u\n",
> +		xfer, length, xfer->tx_done, xfer->rx_len, xfer->rx_done);
> +
> +	if (length > DSI_TX_FIFO_SIZE)
> +		length = DSI_TX_FIFO_SIZE;
> +
> +	xfer->tx_done += length;
> +
> +	/* Send payload */
> +	while (length >= 4) {
> +		reg = get_unaligned_le32(payload);
> +		samsung_dsim_write(dsi, DSIM_PAYLOAD_REG, reg);
> +		payload += 4;
> +		length -= 4;
> +	}
> +
> +	reg = 0;
> +	switch (length) {
> +	case 3:
> +		reg |= payload[2] << 16;
> +		fallthrough;
> +	case 2:
> +		reg |= payload[1] << 8;
> +		fallthrough;
> +	case 1:
> +		reg |= payload[0];
> +		samsung_dsim_write(dsi, DSIM_PAYLOAD_REG, reg);
> +		break;
> +	}
> +
> +	/* Send packet header */
> +	if (!first)
> +		return;
> +
> +	reg = get_unaligned_le32(pkt->header);
> +	if (samsung_dsim_wait_for_hdr_fifo(dsi)) {
> +		dev_err(dev, "waiting for header FIFO timed out\n");
> +		return;
> +	}
> +
> +	if (NEQV(xfer->flags & MIPI_DSI_MSG_USE_LPM,
> +		 dsi->state & DSIM_STATE_CMD_LPM)) {
> +		samsung_dsim_set_cmd_lpm(dsi, xfer->flags & MIPI_DSI_MSG_USE_LPM);
> +		dsi->state ^= DSIM_STATE_CMD_LPM;
> +	}
> +
> +	samsung_dsim_write(dsi, DSIM_PKTHDR_REG, reg);
> +
> +	if (xfer->flags & MIPI_DSI_MSG_REQ_ACK)
> +		samsung_dsim_force_bta(dsi);
> +}
> +
> +static void samsung_dsim_read_from_fifo(struct samsung_dsim *dsi,
> +					struct samsung_dsim_transfer *xfer)
> +{
> +	u8 *payload = xfer->rx_payload + xfer->rx_done;
> +	bool first = !xfer->rx_done;
> +	struct device *dev = dsi->dev;
> +	u16 length;
> +	u32 reg;
> +
> +	if (first) {
> +		reg = samsung_dsim_read(dsi, DSIM_RXFIFO_REG);
> +
> +		switch (reg & 0x3f) {
> +		case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_2BYTE:
> +		case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_2BYTE:
> +			if (xfer->rx_len >= 2) {
> +				payload[1] = reg >> 16;
> +				++xfer->rx_done;
> +			}
> +			fallthrough;
> +		case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_1BYTE:
> +		case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_1BYTE:
> +			payload[0] = reg >> 8;
> +			++xfer->rx_done;
> +			xfer->rx_len = xfer->rx_done;
> +			xfer->result = 0;
> +			goto clear_fifo;
> +		case MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT:
> +			dev_err(dev, "DSI Error Report: 0x%04x\n", (reg >> 8) & 0xffff);
> +			xfer->result = 0;
> +			goto clear_fifo;
> +		}
> +
> +		length = (reg >> 8) & 0xffff;
> +		if (length > xfer->rx_len) {
> +			dev_err(dev,
> +				"response too long (%u > %u bytes), stripping\n",
> +				xfer->rx_len, length);
> +			length = xfer->rx_len;
> +		} else if (length < xfer->rx_len)
> +			xfer->rx_len = length;
> +	}
> +
> +	length = xfer->rx_len - xfer->rx_done;
> +	xfer->rx_done += length;
> +
> +	/* Receive payload */
> +	while (length >= 4) {
> +		reg = samsung_dsim_read(dsi, DSIM_RXFIFO_REG);
> +		payload[0] = (reg >>  0) & 0xff;
> +		payload[1] = (reg >>  8) & 0xff;
> +		payload[2] = (reg >> 16) & 0xff;
> +		payload[3] = (reg >> 24) & 0xff;
> +		payload += 4;
> +		length -= 4;
> +	}
> +
> +	if (length) {
> +		reg = samsung_dsim_read(dsi, DSIM_RXFIFO_REG);
> +		switch (length) {
> +		case 3:
> +			payload[2] = (reg >> 16) & 0xff;
> +			fallthrough;
> +		case 2:
> +			payload[1] = (reg >> 8) & 0xff;
> +			fallthrough;
> +		case 1:
> +			payload[0] = reg & 0xff;
> +		}
> +	}
> +
> +	if (xfer->rx_done == xfer->rx_len)
> +		xfer->result = 0;
> +
> +clear_fifo:
> +	length = DSI_RX_FIFO_SIZE / 4;
> +	do {
> +		reg = samsung_dsim_read(dsi, DSIM_RXFIFO_REG);
> +		if (reg == DSI_RX_FIFO_EMPTY)
> +			break;
> +	} while (--length);
> +}
> +
> +static void samsung_dsim_transfer_start(struct samsung_dsim *dsi)
> +{
> +	unsigned long flags;
> +	struct samsung_dsim_transfer *xfer;
> +	bool start = false;
> +
> +again:
> +	spin_lock_irqsave(&dsi->transfer_lock, flags);
> +
> +	if (list_empty(&dsi->transfer_list)) {
> +		spin_unlock_irqrestore(&dsi->transfer_lock, flags);
> +		return;
> +	}
> +
> +	xfer = list_first_entry(&dsi->transfer_list,
> +				struct samsung_dsim_transfer, list);
> +
> +	spin_unlock_irqrestore(&dsi->transfer_lock, flags);
> +
> +	if (xfer->packet.payload_length &&
> +	    xfer->tx_done == xfer->packet.payload_length)
> +		/* waiting for RX */
> +		return;
> +
> +	samsung_dsim_send_to_fifo(dsi, xfer);
> +
> +	if (xfer->packet.payload_length || xfer->rx_len)
> +		return;
> +
> +	xfer->result = 0;
> +	complete(&xfer->completed);
> +
> +	spin_lock_irqsave(&dsi->transfer_lock, flags);
> +
> +	list_del_init(&xfer->list);
> +	start = !list_empty(&dsi->transfer_list);
> +
> +	spin_unlock_irqrestore(&dsi->transfer_lock, flags);
> +
> +	if (start)
> +		goto again;
> +}
> +
> +static bool samsung_dsim_transfer_finish(struct samsung_dsim *dsi)
> +{
> +	struct samsung_dsim_transfer *xfer;
> +	unsigned long flags;
> +	bool start = true;
> +
> +	spin_lock_irqsave(&dsi->transfer_lock, flags);
> +
> +	if (list_empty(&dsi->transfer_list)) {
> +		spin_unlock_irqrestore(&dsi->transfer_lock, flags);
> +		return false;
> +	}
> +
> +	xfer = list_first_entry(&dsi->transfer_list,
> +				struct samsung_dsim_transfer, list);
> +
> +	spin_unlock_irqrestore(&dsi->transfer_lock, flags);
> +
> +	dev_dbg(dsi->dev,
> +		"> xfer %pK, tx_len %zu, tx_done %u, rx_len %u, rx_done %u\n",
> +		xfer, xfer->packet.payload_length, xfer->tx_done, xfer->rx_len,
> +		xfer->rx_done);
> +
> +	if (xfer->tx_done != xfer->packet.payload_length)
> +		return true;
> +
> +	if (xfer->rx_done != xfer->rx_len)
> +		samsung_dsim_read_from_fifo(dsi, xfer);
> +
> +	if (xfer->rx_done != xfer->rx_len)
> +		return true;
> +
> +	spin_lock_irqsave(&dsi->transfer_lock, flags);
> +
> +	list_del_init(&xfer->list);
> +	start = !list_empty(&dsi->transfer_list);
> +
> +	spin_unlock_irqrestore(&dsi->transfer_lock, flags);
> +
> +	if (!xfer->rx_len)
> +		xfer->result = 0;
> +	complete(&xfer->completed);
> +
> +	return start;
> +}
> +
> +static void samsung_dsim_remove_transfer(struct samsung_dsim *dsi,
> +					 struct samsung_dsim_transfer *xfer)
> +{
> +	unsigned long flags;
> +	bool start;
> +
> +	spin_lock_irqsave(&dsi->transfer_lock, flags);
> +
> +	if (!list_empty(&dsi->transfer_list) &&
> +	    xfer == list_first_entry(&dsi->transfer_list,
> +				     struct samsung_dsim_transfer, list)) {
> +		list_del_init(&xfer->list);
> +		start = !list_empty(&dsi->transfer_list);
> +		spin_unlock_irqrestore(&dsi->transfer_lock, flags);
> +		if (start)
> +			samsung_dsim_transfer_start(dsi);
> +		return;
> +	}
> +
> +	list_del_init(&xfer->list);
> +
> +	spin_unlock_irqrestore(&dsi->transfer_lock, flags);
> +}
> +
> +static int samsung_dsim_transfer(struct samsung_dsim *dsi,
> +				 struct samsung_dsim_transfer *xfer)
> +{
> +	unsigned long flags;
> +	bool stopped;
> +
> +	xfer->tx_done = 0;
> +	xfer->rx_done = 0;
> +	xfer->result = -ETIMEDOUT;
> +	init_completion(&xfer->completed);
> +
> +	spin_lock_irqsave(&dsi->transfer_lock, flags);
> +
> +	stopped = list_empty(&dsi->transfer_list);
> +	list_add_tail(&xfer->list, &dsi->transfer_list);
> +
> +	spin_unlock_irqrestore(&dsi->transfer_lock, flags);
> +
> +	if (stopped)
> +		samsung_dsim_transfer_start(dsi);
> +
> +	wait_for_completion_timeout(&xfer->completed,
> +				    msecs_to_jiffies(DSI_XFER_TIMEOUT_MS));
> +	if (xfer->result == -ETIMEDOUT) {
> +		struct mipi_dsi_packet *pkt = &xfer->packet;
> +
> +		samsung_dsim_remove_transfer(dsi, xfer);
> +		dev_err(dsi->dev, "xfer timed out: %*ph %*ph\n", 4, pkt->header,
> +			(int)pkt->payload_length, pkt->payload);
> +		return -ETIMEDOUT;
> +	}
> +
> +	/* Also covers hardware timeout condition */
> +	return xfer->result;
> +}
> +
> +static irqreturn_t samsung_dsim_irq(int irq, void *dev_id)
> +{
> +	struct samsung_dsim *dsi = dev_id;
> +	u32 status;
> +
> +	status = samsung_dsim_read(dsi, DSIM_INTSRC_REG);
> +	if (!status) {
> +		static unsigned long j;
> +
> +		if (printk_timed_ratelimit(&j, 500))
> +			dev_warn(dsi->dev, "spurious interrupt\n");
> +		return IRQ_HANDLED;
> +	}
> +	samsung_dsim_write(dsi, DSIM_INTSRC_REG, status);
> +
> +	if (status & DSIM_INT_SW_RST_RELEASE) {
> +		u32 mask = ~(DSIM_INT_RX_DONE | DSIM_INT_SFR_FIFO_EMPTY |
> +			DSIM_INT_SFR_HDR_FIFO_EMPTY | DSIM_INT_RX_ECC_ERR |
> +			DSIM_INT_SW_RST_RELEASE);
> +		samsung_dsim_write(dsi, DSIM_INTMSK_REG, mask);
> +		complete(&dsi->completed);
> +		return IRQ_HANDLED;
> +	}
> +
> +	if (!(status & (DSIM_INT_RX_DONE | DSIM_INT_SFR_FIFO_EMPTY |
> +			DSIM_INT_PLL_STABLE)))
> +		return IRQ_HANDLED;
> +
> +	if (samsung_dsim_transfer_finish(dsi))
> +		samsung_dsim_transfer_start(dsi);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static void samsung_dsim_enable_irq(struct samsung_dsim *dsi)
> +{
> +	const struct samsung_dsim_plat_data *pdata = dsi->plat_data;
> +
> +	enable_irq(dsi->irq);
> +
> +	if (pdata && pdata->irq_ops && pdata->irq_ops->enable)
> +		pdata->irq_ops->enable(dsi);
> +}
> +
> +static void samsung_dsim_disable_irq(struct samsung_dsim *dsi)
> +{
> +	const struct samsung_dsim_plat_data *pdata = dsi->plat_data;
> +
> +	if (pdata && pdata->irq_ops && pdata->irq_ops->disable)
> +		pdata->irq_ops->disable(dsi);
> +
> +	disable_irq(dsi->irq);
> +}
> +
> +static int samsung_dsim_init(struct samsung_dsim *dsi)
> +{
> +	const struct samsung_dsim_driver_data *driver_data = dsi->driver_data;
> +
> +	samsung_dsim_reset(dsi);
> +	samsung_dsim_enable_irq(dsi);
> +
> +	if (driver_data->reg_values[RESET_TYPE] == DSIM_FUNCRST)
> +		samsung_dsim_enable_lane(dsi, BIT(dsi->lanes) - 1);
> +
> +	samsung_dsim_enable_clock(dsi);
> +	if (driver_data->wait_for_reset)
> +		samsung_dsim_wait_for_reset(dsi);
> +	samsung_dsim_set_phy_ctrl(dsi);
> +	samsung_dsim_init_link(dsi);
> +
> +	return 0;
> +}
> +
> +static void samsung_dsim_atomic_pre_enable(struct drm_bridge *bridge,
> +					   struct drm_bridge_state *old_bridge_state)
> +{
> +	struct samsung_dsim *dsi = bridge_to_dsi(bridge);
> +	int ret;
> +
> +	if (dsi->state & DSIM_STATE_ENABLED)
> +		return;
> +
> +	ret = pm_runtime_resume_and_get(dsi->dev);
> +	if (ret < 0) {
> +		dev_err(dsi->dev, "failed to enable DSI device.\n");
> +		return;
> +	}
> +
> +	dsi->state |= DSIM_STATE_ENABLED;
> +}
> +
> +static void samsung_dsim_atomic_enable(struct drm_bridge *bridge,
> +				       struct drm_bridge_state *old_bridge_state)
> +{
> +	struct samsung_dsim *dsi = bridge_to_dsi(bridge);
> +
> +	samsung_dsim_set_display_mode(dsi);
> +	samsung_dsim_set_display_enable(dsi, true);
> +
> +	dsi->state |= DSIM_STATE_VIDOUT_AVAILABLE;
> +}
> +
> +static void samsung_dsim_atomic_disable(struct drm_bridge *bridge,
> +					struct drm_bridge_state *old_bridge_state)
> +{
> +	struct samsung_dsim *dsi = bridge_to_dsi(bridge);
> +
> +	if (!(dsi->state & DSIM_STATE_ENABLED))
> +		return;
> +
> +	dsi->state &= ~DSIM_STATE_VIDOUT_AVAILABLE;
> +}
> +
> +static void samsung_dsim_atomic_post_disable(struct drm_bridge *bridge,
> +					     struct drm_bridge_state *old_bridge_state)
> +{
> +	struct samsung_dsim *dsi = bridge_to_dsi(bridge);
> +
> +	samsung_dsim_set_display_enable(dsi, false);
> +
> +	dsi->state &= ~DSIM_STATE_ENABLED;
> +	pm_runtime_put_sync(dsi->dev);
> +}
> +
> +static void samsung_dsim_mode_set(struct drm_bridge *bridge,
> +				  const struct drm_display_mode *mode,
> +				  const struct drm_display_mode *adjusted_mode)
> +{
> +	struct samsung_dsim *dsi = bridge_to_dsi(bridge);
> +
> +	drm_mode_copy(&dsi->mode, adjusted_mode);
> +}
> +
> +static int samsung_dsim_attach(struct drm_bridge *bridge,
> +			       enum drm_bridge_attach_flags flags)
> +{
> +	struct samsung_dsim *dsi = bridge_to_dsi(bridge);
> +
> +	return drm_bridge_attach(bridge->encoder, dsi->out_bridge, NULL, flags);
> +}
> +
> +static const struct drm_bridge_funcs samsung_dsim_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,
> +	.atomic_pre_enable		= samsung_dsim_atomic_pre_enable,
> +	.atomic_enable			= samsung_dsim_atomic_enable,
> +	.atomic_disable			= samsung_dsim_atomic_disable,
> +	.atomic_post_disable		= samsung_dsim_atomic_post_disable,
> +	.mode_set			= samsung_dsim_mode_set,
> +	.attach				= samsung_dsim_attach,
> +};
> +
> +MODULE_DEVICE_TABLE(of, samsung_dsim_of_match);
> +
> +static int samsung_dsim_host_attach(struct mipi_dsi_host *host,
> +				    struct mipi_dsi_device *device)
> +{
> +	struct samsung_dsim *dsi = host_to_dsi(host);
> +	const struct samsung_dsim_plat_data *pdata = dsi->plat_data;
> +	struct device *dev = dsi->dev;
> +	struct drm_panel *panel;
> +	int ret;
> +
> +	panel = of_drm_find_panel(device->dev.of_node);
> +	if (!IS_ERR(panel)) {
> +		dsi->out_bridge = devm_drm_panel_bridge_add(dev, panel);
> +	} else {
> +		dsi->out_bridge = of_drm_find_bridge(device->dev.of_node);
> +		if (!dsi->out_bridge)
> +			dsi->out_bridge = ERR_PTR(-EINVAL);
> +	}
> +
> +	if (IS_ERR(dsi->out_bridge)) {
> +		ret = PTR_ERR(dsi->out_bridge);
> +		DRM_DEV_ERROR(dev, "failed to find the bridge: %d\n", ret);
> +		return ret;
> +	}
> +
> +	DRM_DEV_INFO(dev, "Attached %s device\n", device->name);
> +
> +	drm_bridge_add(&dsi->bridge);
> +
> +	if (pdata && pdata->host_ops && pdata->host_ops->attach) {
> +		ret = pdata->host_ops->attach(dsi, device);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	dsi->lanes = device->lanes;
> +	dsi->format = device->format;
> +	dsi->mode_flags = device->mode_flags;
> +
> +	return 0;
> +}
> +
> +static int samsung_dsim_host_detach(struct mipi_dsi_host *host,
> +				    struct mipi_dsi_device *device)
> +{
> +	struct samsung_dsim *dsi = host_to_dsi(host);
> +	const struct samsung_dsim_plat_data *pdata = dsi->plat_data;
> +	int ret;
> +
> +	if (dsi->out_bridge->funcs->detach)
> +		dsi->out_bridge->funcs->detach(dsi->out_bridge);
> +
> +	dsi->out_bridge = NULL;
> +
> +	if (pdata && pdata->host_ops && pdata->host_ops->detach) {
> +		ret = pdata->host_ops->detach(dsi, device);
> +		if (ret < 0)
> +			return ret;
> +	}
> +
> +	drm_bridge_remove(&dsi->bridge);
> +
> +	return 0;
> +}
> +
> +static ssize_t samsung_dsim_host_transfer(struct mipi_dsi_host *host,
> +					  const struct mipi_dsi_msg *msg)
> +{
> +	struct samsung_dsim *dsi = host_to_dsi(host);
> +	struct samsung_dsim_transfer xfer;
> +	int ret;
> +
> +	if (!(dsi->state & DSIM_STATE_ENABLED))
> +		return -EINVAL;
> +
> +	if (!(dsi->state & DSIM_STATE_INITIALIZED)) {
> +		ret = samsung_dsim_init(dsi);
> +		if (ret)
> +			return ret;
> +		dsi->state |= DSIM_STATE_INITIALIZED;
> +	}
> +
> +	ret = mipi_dsi_create_packet(&xfer.packet, msg);
> +	if (ret < 0)
> +		return ret;
> +
> +	xfer.rx_len = msg->rx_len;
> +	xfer.rx_payload = msg->rx_buf;
> +	xfer.flags = msg->flags;
> +
> +	ret = samsung_dsim_transfer(dsi, &xfer);
> +	return (ret < 0) ? ret : xfer.rx_done;
> +}
> +
> +static const struct mipi_dsi_host_ops samsung_dsim_ops = {
> +	.attach = samsung_dsim_host_attach,
> +	.detach = samsung_dsim_host_detach,
> +	.transfer = samsung_dsim_host_transfer,
> +};
> +
> +static int samsung_dsim_of_read_u32(const struct device_node *np,
> +				    const char *propname, u32 *out_value)
> +{
> +	int ret = of_property_read_u32(np, propname, out_value);
> +
> +	if (ret < 0)
> +		pr_err("%pOF: failed to get '%s' property\n", np, propname);
> +
> +	return ret;
> +}
> +
> +static int samsung_dsim_parse_dt(struct samsung_dsim *dsi)
> +{
> +	struct device *dev = dsi->dev;
> +	struct device_node *node = dev->of_node;
> +	int ret;
> +
> +	ret = samsung_dsim_of_read_u32(node, "samsung,pll-clock-frequency",
> +				       &dsi->pll_clk_rate);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = samsung_dsim_of_read_u32(node, "samsung,burst-clock-frequency",
> +				       &dsi->burst_clk_rate);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = samsung_dsim_of_read_u32(node, "samsung,esc-clock-frequency",
> +				       &dsi->esc_clk_rate);
> +	if (ret < 0)
> +		return ret;
> +
> +	return 0;
> +}
> +
> +__weak const struct samsung_dsim_plat_data *
> +samsung_dsim_plat_probe(struct samsung_dsim *priv)
> +{
> +	return NULL;
> +}
> +
> +__weak void samsung_dsim_plat_remove(struct samsung_dsim *priv)
> +{
> +}
> +
> +static int samsung_dsim_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct samsung_dsim *dsi;
> +	int ret, i;
> +
> +	dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
> +	if (!dsi)
> +		return -ENOMEM;
> +
> +	init_completion(&dsi->completed);
> +	spin_lock_init(&dsi->transfer_lock);
> +	INIT_LIST_HEAD(&dsi->transfer_list);
> +
> +	dsi->dsi_host.ops = &samsung_dsim_ops;
> +	dsi->dsi_host.dev = dev;
> +
> +	dsi->dev = dev;
> +	dsi->driver_data = of_device_get_match_data(dev);
> +
> +	dsi->supplies[0].supply = "vddcore";
> +	dsi->supplies[1].supply = "vddio";
> +	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(dsi->supplies),
> +				      dsi->supplies);
> +	if (ret)
> +		return dev_err_probe(dev, ret, "failed to get regulators\n");
> +
> +	dsi->clks = devm_kcalloc(dev, dsi->driver_data->num_clks,
> +				 sizeof(*dsi->clks), GFP_KERNEL);
> +	if (!dsi->clks)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < dsi->driver_data->num_clks; i++) {
> +		dsi->clks[i] = devm_clk_get(dev, clk_names[i]);
> +		if (IS_ERR(dsi->clks[i])) {
> +			if (strcmp(clk_names[i], "sclk_mipi") == 0) {
> +				dsi->clks[i] = devm_clk_get(dev, OLD_SCLK_MIPI_CLK_NAME);
> +				if (!IS_ERR(dsi->clks[i]))
> +					continue;
> +			}
> +
> +			dev_info(dev, "failed to get the clock: %s\n", clk_names[i]);
> +			return PTR_ERR(dsi->clks[i]);
> +		}
> +	}
> +
> +	dsi->reg_base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(dsi->reg_base))
> +		return PTR_ERR(dsi->reg_base);
> +
> +	dsi->phy = devm_phy_get(dev, "dsim");
> +	if (IS_ERR(dsi->phy)) {
> +		dev_info(dev, "failed to get dsim phy\n");
> +		return PTR_ERR(dsi->phy);
> +	}
> +
> +	dsi->irq = platform_get_irq(pdev, 0);
> +	if (dsi->irq < 0)
> +		return dsi->irq;
> +
> +	ret = devm_request_threaded_irq(dev, dsi->irq, NULL,
> +					samsung_dsim_irq,
> +					IRQF_ONESHOT | IRQF_NO_AUTOEN,
> +					dev_name(dev), dsi);
> +	if (ret) {
> +		dev_err(dev, "failed to request dsi irq\n");
> +		return ret;
> +	}
> +
> +	ret = samsung_dsim_parse_dt(dsi);
> +	if (ret)
> +		return ret;
> +
> +	platform_set_drvdata(pdev, dsi);
> +
> +	pm_runtime_enable(dev);
> +
> +	dsi->bridge.funcs = &samsung_dsim_bridge_funcs;
> +	dsi->bridge.of_node = dev->of_node;
> +	dsi->bridge.type = DRM_MODE_CONNECTOR_DSI;
> +
> +	dsi->plat_data = samsung_dsim_plat_probe(dsi);

The above it a source of the funny race. samsung_dsim_plat_probe() calls 
component_add(). If DSI is the last needed device of the component drm 
device, then this will immediately call bind(), what causes to enter 
exynos_dsi_bind() with dsi->plat_data being NULL. It must be assigned 
inside samsung_dsim_plat_probe(), before calling component_add()

 > ...

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland




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