The patch adds driver for Exynos DSI master (DSIM). It is a platform driver
which is registered as exynos_drm_display sub-driver of exynos_drm framework
and implements DRM encoder/connector pair.
It is also MIPI-DSI host driver and provides DSI bus for panels.
It interacts with its panel(s) using drm_panel framework.

Signed-off-by: Andrzej Hajda <a.hajda at samsung.com>
---
v2:
- add support for DSI message flags,
- add support for new DT properties,
- remove brightness DRM property,
- corrected PM handlers,
- minor fixes/improvements

v3:
- panel attach/detach moved to connector detect callback,
- improved error handling,
- removed exynos_drm_initialize callback,
- added video interface handling,
- moved dsi clock properties to dsi endpoint
---
 drivers/gpu/drm/exynos/Kconfig          |    9 +
 drivers/gpu/drm/exynos/Makefile         |    1 +
 drivers/gpu/drm/exynos/exynos_drm_drv.c |   15 +
 drivers/gpu/drm/exynos/exynos_drm_drv.h |    1 +
 drivers/gpu/drm/exynos/exynos_drm_dsi.c | 1525 +++++++++++++++++++++++++++++++
 5 files changed, 1551 insertions(+)
 create mode 100644 drivers/gpu/drm/exynos/exynos_drm_dsi.c

diff --git a/drivers/gpu/drm/exynos/Kconfig b/drivers/gpu/drm/exynos/Kconfig
index 56f9581..5bf5bca 100644
--- a/drivers/gpu/drm/exynos/Kconfig
+++ b/drivers/gpu/drm/exynos/Kconfig
@@ -39,6 +39,15 @@ config DRM_EXYNOS_DPI
        help
          This enables support for Exynos parallel output.

+config DRM_EXYNOS_DSI
+       bool "EXYNOS DRM MIPI-DSI driver support"
+       depends on DRM_EXYNOS
+       select DRM_MIPI_DSI
+       select DRM_PANEL
+       default n
+       help
+         This enables support for Exynos MIPI-DSI device.
+
 config DRM_EXYNOS_DP
        bool "EXYNOS DRM DP driver support"
        depends on DRM_EXYNOS && ARCH_EXYNOS
diff --git a/drivers/gpu/drm/exynos/Makefile b/drivers/gpu/drm/exynos/Makefile
index babcd52..33ae365 100644
--- a/drivers/gpu/drm/exynos/Makefile
+++ b/drivers/gpu/drm/exynos/Makefile
@@ -12,6 +12,7 @@ exynosdrm-$(CONFIG_DRM_EXYNOS_IOMMU) += exynos_drm_iommu.o
 exynosdrm-$(CONFIG_DRM_EXYNOS_DMABUF) += exynos_drm_dmabuf.o
 exynosdrm-$(CONFIG_DRM_EXYNOS_FIMD)    += exynos_drm_fimd.o
 exynosdrm-$(CONFIG_DRM_EXYNOS_DPI)     += exynos_drm_dpi.o
+exynosdrm-$(CONFIG_DRM_EXYNOS_DSI)     += exynos_drm_dsi.o
 exynosdrm-$(CONFIG_DRM_EXYNOS_DP)      += exynos_dp_core.o exynos_dp_reg.o
 exynosdrm-$(CONFIG_DRM_EXYNOS_HDMI)    += exynos_hdmi.o exynos_mixer.o
 exynosdrm-$(CONFIG_DRM_EXYNOS_VIDI)    += exynos_drm_vidi.o
diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c 
b/drivers/gpu/drm/exynos/exynos_drm_drv.c
index 771c87e..2d27ba2 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_drv.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c
@@ -450,6 +450,12 @@ static int __init exynos_drm_init(void)
                goto out_dp;
 #endif

+#ifdef CONFIG_DRM_EXYNOS_DSI
+       ret = platform_driver_register(&dsi_driver);
+       if (ret < 0)
+               goto out_dsi;
+#endif
+
 #ifdef CONFIG_DRM_EXYNOS_FIMD
        ret = platform_driver_register(&fimd_driver);
        if (ret < 0)
@@ -566,6 +572,11 @@ out_hdmi:
 out_fimd:
 #endif

+#ifdef CONFIG_DRM_EXYNOS_DSI
+       platform_driver_unregister(&dsi_driver);
+out_dsi:
+#endif
+
 #ifdef CONFIG_DRM_EXYNOS_DP
        platform_driver_unregister(&dp_driver);
 out_dp:
@@ -613,6 +624,10 @@ static void __exit exynos_drm_exit(void)
        platform_driver_unregister(&fimd_driver);
 #endif

+#ifdef CONFIG_DRM_EXYNOS_DSI
+       platform_driver_unregister(&dsi_driver);
+#endif
+
 #ifdef CONFIG_DRM_EXYNOS_DP
        platform_driver_unregister(&dp_driver);
 #endif
diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.h 
b/drivers/gpu/drm/exynos/exynos_drm_drv.h
index 2d892f3..4c5cf68 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_drv.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_drv.h
@@ -370,6 +370,7 @@ static inline int exynos_dpi_remove(struct device *dev) { 
return 0; }
 #endif

 extern struct platform_driver dp_driver;
+extern struct platform_driver dsi_driver;
 extern struct platform_driver fimd_driver;
 extern struct platform_driver hdmi_driver;
 extern struct platform_driver mixer_driver;
diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c 
b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
new file mode 100644
index 0000000..697228e
--- /dev/null
+++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
@@ -0,0 +1,1525 @@
+/*
+ * Samsung SoC MIPI DSI Master driver.
+ *
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd
+ *
+ * Contacts: Tomasz Figa <t.figa at samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <drm/drmP.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_panel.h>
+
+#include <linux/clk.h>
+#include <linux/irq.h>
+#include <linux/phy/phy.h>
+#include <linux/regulator/consumer.h>
+
+#include <video/mipi_display.h>
+#include <video/videomode.h>
+
+#include "exynos_drm_drv.h"
+
+/* returns true iff both arguments logically differs */
+#define NEQV(a, b) (!(a) ^ !(b))
+
+#define DSIM_STATUS_REG                0x0     /* Status register */
+#define DSIM_SWRST_REG         0x4     /* Software reset register */
+#define DSIM_CLKCTRL_REG       0x8     /* Clock control register */
+#define DSIM_TIMEOUT_REG       0xc     /* Time out register */
+#define DSIM_CONFIG_REG                0x10    /* Configuration register */
+#define DSIM_ESCMODE_REG       0x14    /* Escape mode register */
+
+/* Main display image resolution register */
+#define DSIM_MDRESOL_REG       0x18
+#define DSIM_MVPORCH_REG       0x1c    /* Main display Vporch register */
+#define DSIM_MHPORCH_REG       0x20    /* Main display Hporch register */
+#define DSIM_MSYNC_REG         0x24    /* Main display sync area register */
+
+/* Sub display image resolution register */
+#define DSIM_SDRESOL_REG       0x28
+#define DSIM_INTSRC_REG                0x2c    /* Interrupt source register */
+#define DSIM_INTMSK_REG                0x30    /* Interrupt mask register */
+#define DSIM_PKTHDR_REG                0x34    /* Packet Header FIFO register 
*/
+#define DSIM_PAYLOAD_REG       0x38    /* Payload FIFO register */
+#define DSIM_RXFIFO_REG                0x3c    /* Read FIFO register */
+#define DSIM_FIFOTHLD_REG      0x40    /* FIFO threshold level register */
+#define DSIM_FIFOCTRL_REG      0x44    /* FIFO status and control register */
+
+/* FIFO memory AC characteristic register */
+#define DSIM_PLLCTRL_REG       0x4c    /* PLL control register */
+#define DSIM_PLLTMR_REG                0x50    /* PLL timer register */
+#define DSIM_PHYACCHR_REG      0x54    /* D-PHY AC characteristic register */
+#define DSIM_PHYACCHR1_REG     0x58    /* D-PHY AC characteristic register1 */
+
+/* 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)
+
+/* 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)            (((x) & 0x7ff) << 16)
+#define DSIM_MAIN_HRESOL(x)            (((x) & 0X7ff) << 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_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)
+
+#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
+
+enum exynos_dsi_transfer_type {
+       EXYNOS_DSI_TX,
+       EXYNOS_DSI_RX,
+};
+
+struct exynos_dsi_transfer {
+       struct list_head list;
+       struct completion completed;
+       int result;
+       u8 data_id;
+       u8 data[2];
+       u16 flags;
+
+       const u8 *tx_payload;
+       u16 tx_len;
+       u16 tx_done;
+
+       u8 *rx_payload;
+       u16 rx_len;
+       u16 rx_done;
+};
+
+#define DSIM_STATE_ENABLED             BIT(0)
+#define DSIM_STATE_INITIALIZED         BIT(1)
+#define DSIM_STATE_CMD_LPM             BIT(2)
+
+struct exynos_dsi {
+       struct mipi_dsi_host dsi_host;
+       struct drm_connector connector;
+       struct drm_encoder *encoder;
+       struct device_node *panel_node;
+       struct drm_panel *panel;
+       struct device *dev;
+
+       void __iomem *reg_base;
+       struct phy *phy;
+       struct clk *pll_clk;
+       struct clk *bus_clk;
+       struct regulator_bulk_data supplies[2];
+       int irq;
+
+       u32 pll_clk_rate;
+       u32 burst_clk_rate;
+       u32 esc_clk_rate;
+       u32 lanes;
+       u32 mode_flags;
+       u32 format;
+       struct videomode vm;
+
+       int state;
+       struct drm_property *brightness;
+       struct completion completed;
+
+       spinlock_t transfer_lock; /* protects transfer_list */
+       struct list_head transfer_list;
+};
+
+#define host_to_dsi(host) container_of(host, struct exynos_dsi, dsi_host)
+#define connector_to_dsi(c) container_of(c, struct exynos_dsi, connector)
+
+static void exynos_dsi_wait_for_reset(struct exynos_dsi *dsi)
+{
+       if (wait_for_completion_timeout(&dsi->completed, msecs_to_jiffies(300)))
+               return;
+
+       dev_err(dsi->dev, "timeout waiting for reset\n");
+}
+
+static void exynos_dsi_reset(struct exynos_dsi *dsi)
+{
+       reinit_completion(&dsi->completed);
+       writel(DSIM_SWRST, dsi->reg_base + DSIM_SWRST_REG);
+}
+
+#ifndef MHZ
+#define MHZ    (1000*1000)
+#endif
+
+static unsigned long exynos_dsi_pll_find_pms(struct exynos_dsi *dsi,
+               unsigned long fin, unsigned long fout, u8 *p, u16 *m, u8 *s)
+{
+       unsigned long best_freq = 0;
+       u32 min_delta = 0xffffffff;
+       u8 p_min, p_max;
+       u8 _p, uninitialized_var(best_p);
+       u16 _m, uninitialized_var(best_m);
+       u8 _s, uninitialized_var(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 > 1000 * 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 exynos_dsi_set_pll(struct exynos_dsi *dsi,
+                                       unsigned long freq)
+{
+       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,
+       };
+       unsigned long fin, fout;
+       int timeout, band;
+       u8 p, s;
+       u16 m;
+       u32 reg;
+
+       clk_set_rate(dsi->pll_clk, dsi->pll_clk_rate);
+
+       fin = clk_get_rate(dsi->pll_clk);
+       if (!fin) {
+               dev_err(dsi->dev, "failed to get PLL clock frequency\n");
+               return 0;
+       }
+
+       dev_dbg(dsi->dev, "PLL input frequency: %lu\n", fin);
+
+       fout = exynos_dsi_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 -EFAULT;
+       }
+
+       for (band = 0; band < ARRAY_SIZE(freq_bands); ++band)
+               if (fout < freq_bands[band])
+                       break;
+
+       dev_dbg(dsi->dev, "PLL freq %lu, (p %d, m %d, s %d), band %d\n", fout,
+               p, m, s, band);
+
+       writel(500, dsi->reg_base + DSIM_PLLTMR_REG);
+
+       reg = DSIM_FREQ_BAND(band) | DSIM_PLL_EN
+                       | DSIM_PLL_P(p) | DSIM_PLL_M(m) | DSIM_PLL_S(s);
+       writel(reg, dsi->reg_base + DSIM_PLLCTRL_REG);
+
+       timeout = 1000;
+       do {
+               if (timeout-- == 0) {
+                       dev_err(dsi->dev, "PLL failed to stabilize\n");
+                       return -EFAULT;
+               }
+               reg = readl(dsi->reg_base + DSIM_STATUS_REG);
+       } while ((reg & DSIM_PLL_STABLE) == 0);
+
+       return fout;
+}
+
+static int exynos_dsi_enable_clock(struct exynos_dsi *dsi)
+{
+       unsigned long hs_clk, byte_clk, esc_clk;
+       unsigned long esc_div;
+       u32 reg;
+
+       hs_clk = exynos_dsi_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 = readl(dsi->reg_base + 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;
+       writel(reg, dsi->reg_base + DSIM_CLKCTRL_REG);
+
+       return 0;
+}
+
+static void exynos_dsi_disable_clock(struct exynos_dsi *dsi)
+{
+       u32 reg;
+
+       reg = readl(dsi->reg_base + DSIM_CLKCTRL_REG);
+       reg &= ~(DSIM_LANE_ESC_CLK_EN_CLK | DSIM_LANE_ESC_CLK_EN_DATA_MASK
+                       | DSIM_ESC_CLKEN | DSIM_BYTE_CLKEN);
+       writel(reg, dsi->reg_base + DSIM_CLKCTRL_REG);
+
+       reg = readl(dsi->reg_base + DSIM_PLLCTRL_REG);
+       reg &= ~DSIM_PLL_EN;
+       writel(reg, dsi->reg_base + DSIM_PLLCTRL_REG);
+}
+
+static int exynos_dsi_init_link(struct exynos_dsi *dsi)
+{
+       int timeout;
+       u32 reg;
+       u32 lanes_mask;
+
+       /* Initialize FIFO pointers */
+       reg = readl(dsi->reg_base + DSIM_FIFOCTRL_REG);
+       reg &= ~0x1f;
+       writel(reg, dsi->reg_base + DSIM_FIFOCTRL_REG);
+
+       usleep_range(9000, 11000);
+
+       reg |= 0x1f;
+       writel(reg, dsi->reg_base + DSIM_FIFOCTRL_REG);
+
+       usleep_range(9000, 11000);
+
+       /* DSI configuration */
+       reg = 0;
+
+       if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
+               reg |= DSIM_VIDEO_MODE;
+
+               if (!(dsi->mode_flags & MIPI_DSI_MODE_VSYNC_FLUSH))
+                       reg |= DSIM_MFLUSH_VS;
+               if (!(dsi->mode_flags & MIPI_DSI_MODE_EOT_PACKET))
+                       reg |= DSIM_EOT_DISABLE;
+               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_HFP))
+                       reg |= DSIM_HFP_MODE;
+               if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_HBP))
+                       reg |= DSIM_HBP_MODE;
+               if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_HSA))
+                       reg |= DSIM_HSA_MODE;
+       }
+
+       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;
+       }
+
+       reg |= DSIM_NUM_OF_DATA_LANE(dsi->lanes - 1);
+
+       writel(reg, dsi->reg_base + DSIM_CONFIG_REG);
+
+       reg |= DSIM_LANE_EN_CLK;
+       writel(reg, dsi->reg_base + DSIM_CONFIG_REG);
+
+       lanes_mask = BIT(dsi->lanes) - 1;
+       reg |= DSIM_LANE_EN(lanes_mask);
+       writel(reg, dsi->reg_base + DSIM_CONFIG_REG);
+
+       /* 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 = readl(dsi->reg_base + 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 = readl(dsi->reg_base + DSIM_ESCMODE_REG);
+       reg &= ~DSIM_STOP_STATE_CNT_MASK;
+       reg |= DSIM_STOP_STATE_CNT(0xf);
+       writel(reg, dsi->reg_base + DSIM_ESCMODE_REG);
+
+       reg = DSIM_BTA_TIMEOUT(0xff) | DSIM_LPDR_TIMEOUT(0xffff);
+       writel(reg, dsi->reg_base + DSIM_TIMEOUT_REG);
+
+       return 0;
+}
+
+static void exynos_dsi_set_display_mode(struct exynos_dsi *dsi)
+{
+       struct videomode *vm = &dsi->vm;
+       u32 reg;
+
+       if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
+               reg = DSIM_CMD_ALLOW(0xf)
+                       | DSIM_STABLE_VFP(vm->vfront_porch)
+                       | DSIM_MAIN_VBP(vm->vback_porch);
+               writel(reg, dsi->reg_base + DSIM_MVPORCH_REG);
+
+               reg = DSIM_MAIN_HFP(vm->hfront_porch)
+                       | DSIM_MAIN_HBP(vm->hback_porch);
+               writel(reg, dsi->reg_base + DSIM_MHPORCH_REG);
+
+               reg = DSIM_MAIN_VSA(vm->vsync_len)
+                       | DSIM_MAIN_HSA(vm->hsync_len);
+               writel(reg, dsi->reg_base + DSIM_MSYNC_REG);
+       }
+
+       reg = DSIM_MAIN_HRESOL(vm->hactive) | DSIM_MAIN_VRESOL(vm->vactive);
+       writel(reg, dsi->reg_base + DSIM_MDRESOL_REG);
+
+       dev_dbg(dsi->dev, "LCD size = %dx%d\n", vm->hactive, vm->vactive);
+}
+
+static void exynos_dsi_set_display_enable(struct exynos_dsi *dsi, bool enable)
+{
+       u32 reg;
+
+       reg = readl(dsi->reg_base + DSIM_MDRESOL_REG);
+       if (enable)
+               reg |= DSIM_MAIN_STAND_BY;
+       else
+               reg &= ~DSIM_MAIN_STAND_BY;
+       writel(reg, dsi->reg_base + DSIM_MDRESOL_REG);
+}
+
+static int exynos_dsi_wait_for_hdr_fifo(struct exynos_dsi *dsi)
+{
+       int timeout = 2000;
+
+       do {
+               u32 reg = readl(dsi->reg_base + DSIM_FIFOCTRL_REG);
+
+               if (!(reg & DSIM_SFR_HEADER_FULL))
+                       return 0;
+
+               if (!cond_resched())
+                       usleep_range(950, 1050);
+       } while (--timeout);
+
+       return -ETIMEDOUT;
+}
+
+static void exynos_dsi_set_cmd_lpm(struct exynos_dsi *dsi, bool lpm)
+{
+       u32 v = readl(dsi->reg_base + DSIM_ESCMODE_REG);
+
+       if (lpm)
+               v |= DSIM_CMD_LPDT_LP;
+       else
+               v &= ~DSIM_CMD_LPDT_LP;
+
+       writel(v, dsi->reg_base + DSIM_ESCMODE_REG);
+}
+
+static void exynos_dsi_force_bta(struct exynos_dsi *dsi)
+{
+       u32 v = readl(dsi->reg_base + DSIM_ESCMODE_REG);
+
+       v |= DSIM_FORCE_BTA;
+       writel(v, dsi->reg_base + DSIM_ESCMODE_REG);
+}
+
+static void exynos_dsi_send_to_fifo(struct exynos_dsi *dsi,
+                                       struct exynos_dsi_transfer *xfer)
+{
+       struct device *dev = dsi->dev;
+       const u8 *payload = xfer->tx_payload + xfer->tx_done;
+       u16 length = xfer->tx_len - xfer->tx_done;
+       bool first = !xfer->tx_done;
+       u32 reg;
+
+       dev_dbg(dev, "< xfer %p: tx len %u, done %u, rx len %u, done %u\n",
+               xfer, xfer->tx_len, 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 = (payload[3] << 24) | (payload[2] << 16)
+                                       | (payload[1] << 8) | payload[0];
+               writel(reg, dsi->reg_base + DSIM_PAYLOAD_REG);
+               payload += 4;
+               length -= 4;
+       }
+
+       reg = 0;
+       switch (length) {
+       case 3:
+               reg |= payload[2] << 16;
+               /* Fall through */
+       case 2:
+               reg |= payload[1] << 8;
+               /* Fall through */
+       case 1:
+               reg |= payload[0];
+               writel(reg, dsi->reg_base + DSIM_PAYLOAD_REG);
+               break;
+       case 0:
+               /* Do nothing */
+               break;
+       }
+
+       /* Send packet header */
+       if (!first)
+               return;
+
+       reg = (xfer->data[1] << 16) | (xfer->data[0] << 8) | xfer->data_id;
+       if (exynos_dsi_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)) {
+               exynos_dsi_set_cmd_lpm(dsi, xfer->flags & MIPI_DSI_MSG_USE_LPM);
+               dsi->state ^= DSIM_STATE_CMD_LPM;
+       }
+
+       writel(reg, dsi->reg_base + DSIM_PKTHDR_REG);
+
+       if (xfer->flags & MIPI_DSI_MSG_REQ_ACK)
+               exynos_dsi_force_bta(dsi);
+}
+
+static void exynos_dsi_read_from_fifo(struct exynos_dsi *dsi,
+                                       struct exynos_dsi_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 = readl(dsi->reg_base + 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;
+                       }
+                       /* Fall through */
+               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 = readl(dsi->reg_base + 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 = readl(dsi->reg_base + DSIM_RXFIFO_REG);
+               switch (length) {
+               case 3:
+                       payload[2] = (reg >> 16) & 0xff;
+                       /* Fall through */
+               case 2:
+                       payload[1] = (reg >> 8) & 0xff;
+                       /* Fall through */
+               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 = readl(dsi->reg_base + DSIM_RXFIFO_REG);
+               if (reg == DSI_RX_FIFO_EMPTY)
+                       break;
+       } while (--length);
+}
+
+static void exynos_dsi_transfer_start(struct exynos_dsi *dsi)
+{
+       unsigned long flags;
+       struct exynos_dsi_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 exynos_dsi_transfer, list);
+
+       spin_unlock_irqrestore(&dsi->transfer_lock, flags);
+
+       if (xfer->tx_len && xfer->tx_done == xfer->tx_len)
+               /* waiting for RX */
+               return;
+
+       exynos_dsi_send_to_fifo(dsi, xfer);
+
+       if (xfer->tx_len || 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 exynos_dsi_transfer_finish(struct exynos_dsi *dsi)
+{
+       struct exynos_dsi_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 exynos_dsi_transfer, list);
+
+       spin_unlock_irqrestore(&dsi->transfer_lock, flags);
+
+       dev_dbg(dsi->dev,
+               "> xfer %p, tx_len %u, tx_done %u, rx_len %u, rx_done %u\n",
+               xfer, xfer->tx_len, xfer->tx_done, xfer->rx_len, xfer->rx_done);
+
+       if (xfer->tx_done != xfer->tx_len)
+               return true;
+
+       if (xfer->rx_done != xfer->rx_len)
+               exynos_dsi_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 exynos_dsi_remove_transfer(struct exynos_dsi *dsi,
+                                       struct exynos_dsi_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 exynos_dsi_transfer, list)) {
+               list_del_init(&xfer->list);
+               start = !list_empty(&dsi->transfer_list);
+               spin_unlock_irqrestore(&dsi->transfer_lock, flags);
+               if (start)
+                       exynos_dsi_transfer_start(dsi);
+               return;
+       }
+
+       list_del_init(&xfer->list);
+
+       spin_unlock_irqrestore(&dsi->transfer_lock, flags);
+}
+
+static int exynos_dsi_transfer(struct exynos_dsi *dsi,
+                                       struct exynos_dsi_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)
+               exynos_dsi_transfer_start(dsi);
+
+       wait_for_completion_timeout(&xfer->completed,
+                                   msecs_to_jiffies(DSI_XFER_TIMEOUT_MS));
+       if (xfer->result == -ETIMEDOUT) {
+               exynos_dsi_remove_transfer(dsi, xfer);
+               dev_err(dsi->dev, "xfer timed out: %*ph %*ph\n", 2, xfer->data,
+                       xfer->tx_len, xfer->tx_payload);
+               return -ETIMEDOUT;
+       }
+
+       /* Also covers hardware timeout condition */
+       return xfer->result;
+}
+
+static irqreturn_t exynos_dsi_irq(int irq, void *dev_id)
+{
+       struct exynos_dsi *dsi = dev_id;
+       u32 status;
+
+       status = readl(dsi->reg_base + DSIM_INTSRC_REG);
+       if (!status) {
+               static unsigned long int j;
+               if (printk_timed_ratelimit(&j, 500))
+                       dev_warn(dsi->dev, "spurious interrupt\n");
+               return IRQ_HANDLED;
+       }
+       writel(status, dsi->reg_base + DSIM_INTSRC_REG);
+
+       if (status & DSIM_INT_SW_RST_RELEASE) {
+               u32 mask = ~(DSIM_INT_RX_DONE | DSIM_INT_SFR_FIFO_EMPTY);
+               writel(mask, dsi->reg_base + DSIM_INTMSK_REG);
+               complete(&dsi->completed);
+               return IRQ_HANDLED;
+       }
+
+       if (!(status & (DSIM_INT_RX_DONE | DSIM_INT_SFR_FIFO_EMPTY)))
+               return IRQ_HANDLED;
+
+       if (exynos_dsi_transfer_finish(dsi))
+               exynos_dsi_transfer_start(dsi);
+
+       return IRQ_HANDLED;
+}
+
+static int exynos_dsi_init(struct exynos_dsi *dsi)
+{
+       exynos_dsi_enable_clock(dsi);
+       exynos_dsi_reset(dsi);
+       enable_irq(dsi->irq);
+       exynos_dsi_wait_for_reset(dsi);
+       exynos_dsi_init_link(dsi);
+
+       return 0;
+}
+
+static int exynos_dsi_host_attach(struct mipi_dsi_host *host,
+                                 struct mipi_dsi_device *device)
+{
+       struct exynos_dsi *dsi = host_to_dsi(host);
+
+       dsi->lanes = device->lanes;
+       dsi->format = device->format;
+       dsi->mode_flags = device->mode_flags;
+       dsi->panel_node = device->dev.of_node;
+
+       if (dsi->connector.dev)
+               drm_helper_hpd_irq_event(dsi->connector.dev);
+
+       return 0;
+}
+
+static int exynos_dsi_host_detach(struct mipi_dsi_host *host,
+                                 struct mipi_dsi_device *device)
+{
+       struct exynos_dsi *dsi = host_to_dsi(host);
+
+       dsi->panel_node = NULL;
+
+       if (dsi->connector.dev)
+               drm_helper_hpd_irq_event(dsi->connector.dev);
+
+       return 0;
+}
+
+/* distinguish between short and long DSI packet types */
+static bool exynos_dsi_is_short_dsi_type(u8 type)
+{
+       return (type & 0x0f) <= 8;
+}
+
+static ssize_t exynos_dsi_host_transfer(struct mipi_dsi_host *host,
+                                      struct mipi_dsi_msg *msg)
+{
+       struct exynos_dsi *dsi = host_to_dsi(host);
+       struct exynos_dsi_transfer xfer;
+       int ret;
+
+       if (!(dsi->state & DSIM_STATE_INITIALIZED)) {
+               ret = exynos_dsi_init(dsi);
+               if (ret)
+                       return ret;
+               dsi->state |= DSIM_STATE_INITIALIZED;
+       }
+
+       if (msg->tx_len == 0)
+               return -EINVAL;
+
+       xfer.data_id = msg->type | (msg->channel << 6);
+
+       if (exynos_dsi_is_short_dsi_type(msg->type)) {
+               const char *tx_buf = msg->tx_buf;
+
+               if (msg->tx_len > 2)
+                       return -EINVAL;
+               xfer.tx_len = 0;
+               xfer.data[0] = tx_buf[0];
+               xfer.data[1] = (msg->tx_len == 2) ? tx_buf[1] : 0;
+       } else {
+               xfer.tx_len = msg->tx_len;
+               xfer.data[0] = msg->tx_len & 0xff;
+               xfer.data[1] = msg->tx_len >> 8;
+               xfer.tx_payload = msg->tx_buf;
+       }
+
+       xfer.rx_len = msg->rx_len;
+       xfer.rx_payload = msg->rx_buf;
+       xfer.flags = msg->flags;
+
+       ret = exynos_dsi_transfer(dsi, &xfer);
+       return (ret < 0) ? ret : xfer.rx_done;
+}
+
+static const struct mipi_dsi_host_ops exynos_dsi_ops = {
+       .attach = exynos_dsi_host_attach,
+       .detach = exynos_dsi_host_detach,
+       .transfer = exynos_dsi_host_transfer,
+};
+
+static int exynos_dsi_poweron(struct exynos_dsi *dsi)
+{
+       int ret;
+
+       ret = regulator_bulk_enable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
+       if (ret < 0) {
+               dev_err(dsi->dev, "cannot enable regulators %d\n", ret);
+               return ret;
+       }
+
+       ret = clk_prepare_enable(dsi->bus_clk);
+       if (ret < 0) {
+               dev_err(dsi->dev, "cannot enable bus clock %d\n", ret);
+               goto err_bus_clk;
+       }
+
+       ret = clk_prepare_enable(dsi->pll_clk);
+       if (ret < 0) {
+               dev_err(dsi->dev, "cannot enable pll clock %d\n", ret);
+               goto err_pll_clk;
+       }
+
+       ret = phy_power_on(dsi->phy);
+       if (ret < 0) {
+               dev_err(dsi->dev, "cannot enable phy %d\n", ret);
+               goto err_phy;
+       }
+
+       return 0;
+
+err_phy:
+       clk_disable_unprepare(dsi->pll_clk);
+err_pll_clk:
+       clk_disable_unprepare(dsi->bus_clk);
+err_bus_clk:
+       regulator_bulk_disable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
+
+       return ret;
+}
+
+static void exynos_dsi_poweroff(struct exynos_dsi *dsi)
+{
+       int ret;
+
+       usleep_range(10000, 20000);
+
+       if (dsi->state & DSIM_STATE_INITIALIZED) {
+               dsi->state &= ~DSIM_STATE_INITIALIZED;
+
+               exynos_dsi_disable_clock(dsi);
+
+               disable_irq(dsi->irq);
+       }
+
+       dsi->state &= ~DSIM_STATE_CMD_LPM;
+
+       phy_power_off(dsi->phy);
+
+       clk_disable_unprepare(dsi->pll_clk);
+       clk_disable_unprepare(dsi->bus_clk);
+
+       ret = regulator_bulk_disable(ARRAY_SIZE(dsi->supplies), dsi->supplies);
+       if (ret < 0)
+               dev_err(dsi->dev, "cannot disable regulators %d\n", ret);
+}
+
+static int exynos_dsi_enable(struct exynos_dsi *dsi)
+{
+       int ret;
+
+       if (dsi->state & DSIM_STATE_ENABLED)
+               return 0;
+
+       ret = exynos_dsi_poweron(dsi);
+       if (ret < 0)
+               return ret;
+
+       ret = drm_panel_enable(dsi->panel);
+       if (ret < 0) {
+               exynos_dsi_poweroff(dsi);
+               return ret;
+       }
+
+       exynos_dsi_set_display_mode(dsi);
+       exynos_dsi_set_display_enable(dsi, true);
+
+       dsi->state |= DSIM_STATE_ENABLED;
+
+       return 0;
+}
+
+static void exynos_dsi_disable(struct exynos_dsi *dsi)
+{
+       if (!(dsi->state & DSIM_STATE_ENABLED))
+               return;
+
+       exynos_dsi_set_display_enable(dsi, false);
+       drm_panel_disable(dsi->panel);
+       exynos_dsi_poweroff(dsi);
+
+       dsi->state &= ~DSIM_STATE_ENABLED;
+}
+
+static void exynos_dsi_dpms(struct exynos_drm_display *display, int mode)
+{
+       struct exynos_dsi *dsi = display->ctx;
+
+       if (dsi->panel) {
+               switch (mode) {
+               case DRM_MODE_DPMS_ON:
+                       exynos_dsi_enable(dsi);
+                       break;
+               case DRM_MODE_DPMS_STANDBY:
+               case DRM_MODE_DPMS_SUSPEND:
+               case DRM_MODE_DPMS_OFF:
+                       exynos_dsi_disable(dsi);
+                       break;
+               default:
+                       break;
+               }
+       }
+}
+
+static enum drm_connector_status
+exynos_dsi_detect(struct drm_connector *connector, bool force)
+{
+       struct exynos_dsi *dsi = connector_to_dsi(connector);
+
+       if (!dsi->panel) {
+               dsi->panel = of_drm_find_panel(dsi->panel_node);
+               if (dsi->panel)
+                       drm_panel_attach(dsi->panel, &dsi->connector);
+       } else if (!dsi->panel_node) {
+               struct exynos_drm_display *display;
+
+               display = platform_get_drvdata(to_platform_device(dsi->dev));
+               exynos_dsi_dpms(display, DRM_MODE_DPMS_OFF);
+               drm_panel_detach(dsi->panel);
+               dsi->panel = NULL;
+       }
+
+       if (dsi->panel)
+               return connector_status_connected;
+
+       return connector_status_disconnected;
+}
+
+static void exynos_dsi_connector_destroy(struct drm_connector *connector)
+{
+}
+
+static struct drm_connector_funcs exynos_dsi_connector_funcs = {
+       .dpms = drm_helper_connector_dpms,
+       .detect = exynos_dsi_detect,
+       .fill_modes = drm_helper_probe_single_connector_modes,
+       .destroy = exynos_dsi_connector_destroy,
+};
+
+static int exynos_dsi_get_modes(struct drm_connector *connector)
+{
+       struct exynos_dsi *dsi = connector_to_dsi(connector);
+
+       if (dsi->panel)
+               return dsi->panel->funcs->get_modes(dsi->panel);
+
+       return 0;
+}
+
+static int exynos_dsi_mode_valid(struct drm_connector *connector,
+                                struct drm_display_mode *mode)
+{
+       return MODE_OK;
+}
+
+static struct drm_encoder *
+exynos_dsi_best_encoder(struct drm_connector *connector)
+{
+       struct exynos_dsi *dsi = connector_to_dsi(connector);
+
+       return dsi->encoder;
+}
+
+static struct drm_connector_helper_funcs exynos_dsi_connector_helper_funcs = {
+       .get_modes = exynos_dsi_get_modes,
+       .mode_valid = exynos_dsi_mode_valid,
+       .best_encoder = exynos_dsi_best_encoder,
+};
+
+static int exynos_dsi_create_connector(struct exynos_drm_display *display,
+                                      struct drm_encoder *encoder)
+{
+       struct exynos_dsi *dsi = display->ctx;
+       struct drm_connector *connector = &dsi->connector;
+       int ret;
+
+       dsi->encoder = encoder;
+
+       connector->polled = DRM_CONNECTOR_POLL_HPD;
+
+       ret = drm_connector_init(encoder->dev, connector,
+                                &exynos_dsi_connector_funcs,
+                                DRM_MODE_CONNECTOR_DSI);
+       if (ret) {
+               DRM_ERROR("Failed to initialize connector with drm\n");
+               return ret;
+       }
+
+       drm_connector_helper_add(connector, &exynos_dsi_connector_helper_funcs);
+       drm_sysfs_connector_add(connector);
+       drm_mode_connector_attach_encoder(connector, encoder);
+
+       return 0;
+}
+
+static void exynos_dsi_mode_set(struct exynos_drm_display *display,
+                        struct drm_display_mode *mode)
+{
+       struct exynos_dsi *dsi = display->ctx;
+       struct videomode *vm = &dsi->vm;
+
+       vm->hactive = mode->hdisplay;
+       vm->vactive = mode->vdisplay;
+       vm->vfront_porch = mode->vsync_start - mode->vdisplay;
+       vm->vback_porch = mode->vtotal - mode->vsync_end;
+       vm->vsync_len = mode->vsync_end - mode->vsync_start;
+       vm->hfront_porch = mode->hsync_start - mode->hdisplay;
+       vm->hback_porch = mode->htotal - mode->hsync_end;
+       vm->hsync_len = mode->hsync_end - mode->hsync_start;
+}
+
+static struct exynos_drm_display_ops exynos_dsi_display_ops = {
+       .create_connector = exynos_dsi_create_connector,
+       .mode_set = exynos_dsi_mode_set,
+       .dpms = exynos_dsi_dpms
+};
+
+static struct exynos_drm_display exynos_dsi_display = {
+       .type = EXYNOS_DISPLAY_TYPE_LCD,
+       .ops = &exynos_dsi_display_ops,
+};
+
+/* of_* functions will be removed after merge of of_graph patches */
+static struct device_node *
+of_get_child_by_name_reg(struct device_node *parent, const char *name, u32 reg)
+{
+       struct device_node *np;
+
+       for_each_child_of_node(parent, np) {
+               u32 r;
+
+               if (!np->name || of_node_cmp(np->name, name))
+                       continue;
+
+               if (of_property_read_u32(np, "reg", &r) < 0)
+                       r = 0;
+
+               if (reg == r)
+                       break;
+       }
+
+       return np;
+}
+
+static struct device_node *of_graph_get_port_by_reg(struct device_node *parent,
+                                                   u32 reg)
+{
+       struct device_node *ports, *port;
+
+       ports = of_get_child_by_name(parent, "ports");
+       if (ports)
+               parent = ports;
+
+       port = of_get_child_by_name_reg(parent, "port", reg);
+
+       of_node_put(ports);
+
+       return port;
+}
+
+static struct device_node *
+of_graph_get_endpoint_by_reg(struct device_node *port, u32 reg)
+{
+       return of_get_child_by_name_reg(port, "endpoint", reg);
+}
+
+static int exynos_dsi_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("%s: failed to get '%s' property\n", np->full_name,
+                      propname);
+
+       return ret;
+}
+
+enum {
+       DSI_PORT_IN,
+       DSI_PORT_OUT
+};
+
+static int exynos_dsi_parse_dt(struct exynos_dsi *dsi)
+{
+       struct device *dev = dsi->dev;
+       struct device_node *node = dev->of_node;
+       struct device_node *port, *ep;
+       int ret;
+
+       ret = exynos_dsi_of_read_u32(node, "samsung,pll-clock-frequency",
+                                    &dsi->pll_clk_rate);
+       if (ret < 0)
+               return ret;
+
+       port = of_graph_get_port_by_reg(node, DSI_PORT_OUT);
+       if (!port) {
+               dev_err(dev, "no output port specified\n");
+               return -EINVAL;
+       }
+
+       ep = of_graph_get_endpoint_by_reg(port, 0);
+       of_node_put(port);
+       if (!ep) {
+               dev_err(dev, "no endpoint specified in output port\n");
+               return -EINVAL;
+       }
+
+       ret = exynos_dsi_of_read_u32(ep, "samsung,burst-clock-frequency",
+                                    &dsi->burst_clk_rate);
+       if (ret < 0)
+               goto end;
+
+       ret = exynos_dsi_of_read_u32(ep, "samsung,esc-clock-frequency",
+                                    &dsi->esc_clk_rate);
+
+end:
+       of_node_put(ep);
+
+       return ret;
+}
+
+static int exynos_dsi_probe(struct platform_device *pdev)
+{
+       struct resource *res;
+       struct exynos_dsi *dsi;
+       int ret;
+
+       dsi = devm_kzalloc(&pdev->dev, sizeof(*dsi), GFP_KERNEL);
+       if (!dsi) {
+               dev_err(&pdev->dev, "failed to allocate dsi object.\n");
+               return -ENOMEM;
+       }
+
+       init_completion(&dsi->completed);
+       spin_lock_init(&dsi->transfer_lock);
+       INIT_LIST_HEAD(&dsi->transfer_list);
+
+       dsi->dsi_host.ops = &exynos_dsi_ops;
+       dsi->dsi_host.dev = &pdev->dev;
+
+       dsi->dev = &pdev->dev;
+
+       ret = exynos_dsi_parse_dt(dsi);
+       if (ret)
+               return ret;
+
+       dsi->supplies[0].supply = "vddcore";
+       dsi->supplies[1].supply = "vddio";
+       ret = devm_regulator_bulk_get(&pdev->dev, ARRAY_SIZE(dsi->supplies),
+                                     dsi->supplies);
+       if (ret) {
+               dev_info(&pdev->dev, "failed to get regulators: %d\n", ret);
+               return -EPROBE_DEFER;
+       }
+
+       dsi->pll_clk = devm_clk_get(&pdev->dev, "pll_clk");
+       if (IS_ERR(dsi->pll_clk)) {
+               dev_info(&pdev->dev, "failed to get dsi pll input clock\n");
+               return -EPROBE_DEFER;
+       }
+
+       dsi->bus_clk = devm_clk_get(&pdev->dev, "bus_clk");
+       if (IS_ERR(dsi->bus_clk)) {
+               dev_info(&pdev->dev, "failed to get dsi bus clock\n");
+               return -EPROBE_DEFER;
+       }
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       dsi->reg_base = devm_ioremap_resource(&pdev->dev, res);
+       if (!dsi->reg_base) {
+               dev_err(&pdev->dev, "failed to remap io region\n");
+               return -EADDRNOTAVAIL;
+       }
+
+       dsi->phy = devm_phy_get(&pdev->dev, "dsim");
+       if (IS_ERR(dsi->phy)) {
+               dev_info(&pdev->dev, "failed to get dsim phy\n");
+               return -EPROBE_DEFER;
+       }
+
+       dsi->irq = platform_get_irq(pdev, 0);
+       if (dsi->irq < 0) {
+               dev_err(&pdev->dev, "failed to request dsi irq resource\n");
+               return dsi->irq;
+       }
+
+       irq_set_status_flags(dsi->irq, IRQ_NOAUTOEN);
+       ret = devm_request_threaded_irq(&pdev->dev, dsi->irq, NULL,
+                                       exynos_dsi_irq, IRQF_ONESHOT,
+                                       dev_name(&pdev->dev), dsi);
+       if (ret) {
+               dev_err(&pdev->dev, "failed to request dsi irq\n");
+               return ret;
+       }
+
+       exynos_dsi_display.ctx = dsi;
+
+       platform_set_drvdata(pdev, &exynos_dsi_display);
+       exynos_drm_display_register(&exynos_dsi_display);
+
+       return mipi_dsi_host_register(&dsi->dsi_host);
+}
+
+static int exynos_dsi_remove(struct platform_device *pdev)
+{
+       struct exynos_dsi *dsi = exynos_dsi_display.ctx;
+
+       exynos_dsi_dpms(&exynos_dsi_display, DRM_MODE_DPMS_OFF);
+
+       exynos_drm_display_unregister(&exynos_dsi_display);
+       mipi_dsi_host_unregister(&dsi->dsi_host);
+
+       return 0;
+}
+
+#if CONFIG_PM_SLEEP
+static int exynos_dsi_resume(struct device *dev)
+{
+       struct exynos_dsi *dsi = exynos_dsi_display.ctx;
+
+       if (dsi->state & DSIM_STATE_ENABLED) {
+               dsi->state &= ~DSIM_STATE_ENABLED;
+               exynos_dsi_enable(dsi);
+       }
+
+       return 0;
+}
+
+static int exynos_dsi_suspend(struct device *dev)
+{
+       struct exynos_dsi *dsi = exynos_dsi_display.ctx;
+
+       if (dsi->state & DSIM_STATE_ENABLED) {
+               exynos_dsi_disable(dsi);
+               dsi->state |= DSIM_STATE_ENABLED;
+       }
+
+       return 0;
+}
+#endif
+
+static const struct dev_pm_ops exynos_dsi_pm_ops = {
+       SET_SYSTEM_SLEEP_PM_OPS(exynos_dsi_suspend, exynos_dsi_resume)
+};
+
+static struct of_device_id exynos_dsi_of_match[] = {
+       { .compatible = "samsung,exynos4210-mipi-dsi" },
+       { }
+};
+
+MODULE_DEVICE_TABLE(of, exynos_dsi_of_match);
+struct platform_driver dsi_driver = {
+       .probe = exynos_dsi_probe,
+       .remove = exynos_dsi_remove,
+       .driver = {
+                  .name = "exynos-dsi",
+                  .owner = THIS_MODULE,
+                  .pm = &exynos_dsi_pm_ops,
+                  .of_match_table = exynos_dsi_of_match,
+       },
+};
+
+MODULE_AUTHOR("Tomasz Figa <t.figa at samsung.com>");
+MODULE_AUTHOR("Andrzej Hajda <a.hajda at samsung.com>");
+MODULE_DESCRIPTION("Samsung SoC MIPI DSI Master");
+MODULE_LICENSE("GPL v2");
-- 
1.8.3.2

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