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From:   Sandor Yu <sandor.yu@nxp.com>
To:     Alexander Stein <alexander.stein@ew.tq-group.com>,
        "dmitry.baryshkov@linaro.org" <dmitry.baryshkov@linaro.org>,
        "andrzej.hajda@intel.com" <andrzej.hajda@intel.com>,
        "neil.armstrong@linaro.org" <neil.armstrong@linaro.org>,
        "Laurent.pinchart@ideasonboard.com" 
        <Laurent.pinchart@ideasonboard.com>,
        "jonas@kwiboo.se" <jonas@kwiboo.se>,
        "jernej.skrabec@gmail.com" <jernej.skrabec@gmail.com>,
        "airlied@gmail.com" <airlied@gmail.com>,
        "daniel@ffwll.ch" <daniel@ffwll.ch>,
        "robh+dt@kernel.org" <robh+dt@kernel.org>,
        "krzysztof.kozlowski+dt@linaro.org" 
        <krzysztof.kozlowski+dt@linaro.org>,
        "shawnguo@kernel.org" <shawnguo@kernel.org>,
        "s.hauer@pengutronix.de" <s.hauer@pengutronix.de>,
        "festevam@gmail.com" <festevam@gmail.com>,
        "vkoul@kernel.org" <vkoul@kernel.org>,
        "dri-devel@lists.freedesktop.org" <dri-devel@lists.freedesktop.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
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        <linux-arm-kernel@lists.infradead.org>,
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        "linux-phy@lists.infradead.org" <linux-phy@lists.infradead.org>
CC:     "kernel@pengutronix.de" <kernel@pengutronix.de>,
        dl-linux-imx <linux-imx@nxp.com>,
        Oliver Brown <oliver.brown@nxp.com>,
        "sam@ravnborg.org" <sam@ravnborg.org>
Subject: RE: [EXT] Re: [PATCH v10 1/7] drm: bridge: Cadence: Creat mhdp helper
 driver
Thread-Topic: [EXT] Re: [PATCH v10 1/7] drm: bridge: Cadence: Creat mhdp
 helper driver
Thread-Index: AQHZ/YCho5kXVsQF4U27TlHQArLRzLBHUtUAgAA6AfA=
Date:   Mon, 16 Oct 2023 03:05:54 +0000
Message-ID: <PAXPR04MB9448AC9D8090E1F5F7E39C0EF4D7A@PAXPR04MB9448.eurprd04.prod.outlook.com>
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Hi Alexander,

Thanks your comments,

>=20
> Hi Sandor,
>=20
> thanks for the updated series.
>=20
> Am Freitag, 13. Oktober 2023, 05:24:20 CEST schrieb Sandor Yu:
> > MHDP8546 mailbox access functions will be share to other mhdp driver
> > and Cadence HDP-TX HDMI/DP PHY drivers.
> > Create a new mhdp helper driver and move all those functions into.
> >
> > cdns_mhdp_reg_write() is renamed to cdns_mhdp_dp_reg_write(), because
> > it use the DPTX command ID DPTX_WRITE_REGISTER.
> >
> > New cdns_mhdp_reg_write() is created with the general command ID
> > GENERAL_REGISTER_WRITE.
> >
> > Signed-off-by: Sandor Yu <Sandor.yu@nxp.com>
> > ---
> > v9->v10:
> >  *use mhdp helper driver to replace macro functions,  move maibox
> > access function and mhdp hdmi/dp common API  functions into the
> > driver.
> >
> >  drivers/gpu/drm/bridge/cadence/Kconfig        |   4
> >  drivers/gpu/drm/bridge/cadence/Makefile       |   1 +
> >  .../gpu/drm/bridge/cadence/cdns-mhdp-helper.c | 306 ++++++++++++++
> >  .../drm/bridge/cadence/cdns-mhdp8546-core.c   | 383 +++---------------
> >  .../drm/bridge/cadence/cdns-mhdp8546-core.h   |  44 +-
> >  include/drm/bridge/cdns-mhdp-helper.h         |  96 +++++
> >  6 files changed, 473 insertions(+), 361 deletions(-)  create mode
> > 100644 drivers/gpu/drm/bridge/cadence/cdns-mhdp-helper.c
> >  create mode 100644 include/drm/bridge/cdns-mhdp-helper.h
> >
> > diff --git a/drivers/gpu/drm/bridge/cadence/Kconfig
> > b/drivers/gpu/drm/bridge/cadence/Kconfig index
> > ec35215a20034..0b7b4626a7af0
> > 100644
> > --- a/drivers/gpu/drm/bridge/cadence/Kconfig
> > +++ b/drivers/gpu/drm/bridge/cadence/Kconfig
> > @@ -20,6 +20,9 @@ config DRM_CDNS_DSI_J721E
> >         the routing of the DSS DPI signal to the Cadence DSI.
> >  endif
> >
> > +config CDNS_MHDP_HELPER
> > +     tristate
> > +
> >  config DRM_CDNS_MHDP8546
> >       tristate "Cadence DPI/DP bridge"
> >       select DRM_DISPLAY_DP_HELPER
> > @@ -27,6 +30,7 @@ config DRM_CDNS_MHDP8546
> >       select DRM_DISPLAY_HELPER
> >       select DRM_KMS_HELPER
> >       select DRM_PANEL_BRIDGE
> > +     select CDNS_MHDP_HELPER
> >       depends on OF
> >       help
> >         Support Cadence DPI to DP bridge. This is an internal diff
> > --git a/drivers/gpu/drm/bridge/cadence/Makefile
> > b/drivers/gpu/drm/bridge/cadence/Makefile index
> > c95fd5b81d137..087dc074820d7 100644
> > --- a/drivers/gpu/drm/bridge/cadence/Makefile
> > +++ b/drivers/gpu/drm/bridge/cadence/Makefile
> > @@ -2,6 +2,7 @@
> >  obj-$(CONFIG_DRM_CDNS_DSI) +=3D cdns-dsi.o  cdns-dsi-y :=3D
> > cdns-dsi-core.o
> >  cdns-dsi-$(CONFIG_DRM_CDNS_DSI_J721E) +=3D cdns-dsi-j721e.o
> > +obj-$(CONFIG_CDNS_MHDP_HELPER) +=3D cdns-mhdp-helper.o
> >  obj-$(CONFIG_DRM_CDNS_MHDP8546) +=3D cdns-mhdp8546.o
> cdns-mhdp8546-y
> > :=3D cdns-mhdp8546-core.o cdns-mhdp8546-hdcp.o
> >  cdns-mhdp8546-$(CONFIG_DRM_CDNS_MHDP8546_J721E) +=3D
> > cdns-mhdp8546-j721e.o diff --git
> > a/drivers/gpu/drm/bridge/cadence/cdns-mhdp-helper.c
> > b/drivers/gpu/drm/bridge/cadence/cdns-mhdp-helper.c new file mode
> > 100644 index 0000000000000..2e3eee40494f0
> > --- /dev/null
> > +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp-helper.c
> > @@ -0,0 +1,306 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * Copyright (C) 2023 NXP Semiconductor, Inc.
> > + *
> > + */
> > +#include <drm/bridge/cdns-mhdp-helper.h> #include
> > +<linux/dev_printk.h> #include <linux/module.h>
> > +
> > +/* Mailbox helper functions */
> > +int cdns_mhdp_mailbox_read(struct cdns_mhdp_base *base) {
> > +     int ret, empty;
> > +
> > +     WARN_ON(!mutex_is_locked(base->mbox_mutex));
> > +
> > +     ret =3D readx_poll_timeout(readl, base->regs +
> CDNS_MAILBOX_EMPTY,
> > +                              empty, !empty, MAILBOX_RETRY_US,
> > +                              MAILBOX_TIMEOUT_US);
> > +     if (ret < 0)
> > +             return ret;
> > +
> > +     return readl(base->regs + CDNS_MAILBOX_RX_DATA) & 0xff; }
> > +EXPORT_SYMBOL_GPL(cdns_mhdp_mailbox_read);
>=20
> No need to export this. You can make this function actually static.

OK, I will change it to static in the next version.

>=20
> > +
> > +int cdns_mhdp_mailbox_write(struct cdns_mhdp_base *base, u8 val) {
> > +     int ret, full;
> > +
> > +     WARN_ON(!mutex_is_locked(base->mbox_mutex));
> > +
> > +     ret =3D readx_poll_timeout(readl, base->regs + CDNS_MAILBOX_FULL,
> > +                              full, !full, MAILBOX_RETRY_US,
> > +                              MAILBOX_TIMEOUT_US);
> > +     if (ret < 0)
> > +             return ret;
> > +
> > +     writel(val, base->regs + CDNS_MAILBOX_TX_DATA);
> > +
> > +     return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(cdns_mhdp_mailbox_write);
>=20
> No need to export that one as well. You can make this function actually s=
tatic
> as these two functions are only called from the helper itself.

mhdp8546 driver need this function.=20

>=20
> > +
> > +int cdns_mhdp_mailbox_recv_header(struct cdns_mhdp_base *base,
> > +                               u8 module_id, u8 opcode,
> > +                               u16 req_size) {
> > +     u32 mbox_size, i;
> > +     u8 header[4];
> > +     int ret;
> > +
> > +     /* read the header of the message */
> > +     for (i =3D 0; i < sizeof(header); i++) {
> > +             ret =3D cdns_mhdp_mailbox_read(base);
> > +             if (ret < 0)
> > +                     return ret;
> > +
> > +             header[i] =3D ret;
> > +     }
> > +
> > +     mbox_size =3D get_unaligned_be16(header + 2);
> > +
> > +     if (opcode !=3D header[0] || module_id !=3D header[1] ||
> > +         req_size !=3D mbox_size) {
> > +             /*
> > +              * If the message in mailbox is not what we want, we
> > + need
> to
> > +              * clear the mailbox by reading its contents.
> > +              */
> > +             for (i =3D 0; i < mbox_size; i++)
> > +                     if (cdns_mhdp_mailbox_read(base) < 0)
> > +                             break;
> > +
> > +             return -EINVAL;
> > +     }
> > +
> > +     return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(cdns_mhdp_mailbox_recv_header);
> > +
> > +int cdns_mhdp_mailbox_recv_data(struct cdns_mhdp_base *base,
> > +                             u8 *buff, u16 buff_size) {
> > +     u32 i;
> > +     int ret;
> > +
> > +     for (i =3D 0; i < buff_size; i++) {
> > +             ret =3D cdns_mhdp_mailbox_read(base);
> > +             if (ret < 0)
> > +                     return ret;
> > +
> > +             buff[i] =3D ret;
> > +     }
> > +
> > +     return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(cdns_mhdp_mailbox_recv_data);
> > +
> > +int cdns_mhdp_mailbox_send(struct cdns_mhdp_base *base, u8
> module_id,
> > +                        u8 opcode, u16 size, u8 *message) {
> > +     u8 header[4];
> > +     int ret, i;
> > +
> > +     header[0] =3D opcode;
> > +     header[1] =3D module_id;
> > +     put_unaligned_be16(size, header + 2);
> > +
> > +     for (i =3D 0; i < sizeof(header); i++) {
> > +             ret =3D cdns_mhdp_mailbox_write(base, header[i]);
> > +             if (ret)
> > +                     return ret;
> > +     }
> > +
> > +     for (i =3D 0; i < size; i++) {
> > +             ret =3D cdns_mhdp_mailbox_write(base, message[i]);
> > +             if (ret)
> > +                     return ret;
> > +     }
> > +
> > +     return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(cdns_mhdp_mailbox_send);
> > +
> > +/* General helper functions */
> > +int cdns_mhdp_reg_read(struct cdns_mhdp_base *base, u32 addr, u32
> > +*value) {
> > +     u8 msg[4], resp[8];
> > +     int ret;
> > +
> > +     put_unaligned_be32(addr, msg);
> > +
> > +     mutex_lock(base->mbox_mutex);
> > +
> > +     ret =3D cdns_mhdp_mailbox_send(base, MB_MODULE_ID_GENERAL,
> > +                                  GENERAL_REGISTER_READ,
> > +                                  sizeof(msg), msg);
> > +     if (ret)
> > +             goto out;
> > +
> > +     ret =3D cdns_mhdp_mailbox_recv_header(base,
> MB_MODULE_ID_GENERAL,
> > +
> GENERAL_REGISTER_READ,
> > +                                         sizeof(resp));
> > +     if (ret)
> > +             goto out;
> > +
> > +     ret =3D cdns_mhdp_mailbox_recv_data(base, resp, sizeof(resp));
> > +     if (ret)
> > +             goto out;
> > +
> > +     /* Returned address value should be the same as requested */
> > +     if (memcmp(msg, resp, sizeof(msg))) {
> > +             ret =3D -EINVAL;
> > +             goto out;
> > +     }
> > +
> > +     *value =3D get_unaligned_be32(resp + 4);
> > +
> > +out:
> > +     mutex_unlock(base->mbox_mutex);
> > +     if (ret) {
> > +             dev_err(base->dev, "Failed to read register\n");
> > +             *value =3D 0;
> > +     }
> > +
> > +     return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(cdns_mhdp_reg_read);
> > +
> > +int cdns_mhdp_reg_write(struct cdns_mhdp_base *base, u32 addr, u32
> > +val) {
> > +     u8 msg[8];
> > +     int ret;
> > +
> > +     put_unaligned_be32(addr, msg);
> > +     put_unaligned_be32(val, msg + 4);
> > +
> > +     mutex_lock(base->mbox_mutex);
> > +
> > +     ret =3D cdns_mhdp_mailbox_send(base, MB_MODULE_ID_GENERAL,
> > +                                  GENERAL_REGISTER_WRITE,
> > +                                  sizeof(msg), msg);
> > +
> > +     mutex_unlock(base->mbox_mutex);
> > +
> > +     return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(cdns_mhdp_reg_write);
> > +
> > +/* DPTX helper functions */
> > +int cdns_mhdp_dp_reg_write(struct cdns_mhdp_base *base, u16 addr,
> u32
> > +val) {
> > +     u8 msg[6];
> > +     int ret;
> > +
> > +     put_unaligned_be16(addr, msg);
> > +     put_unaligned_be32(val, msg + 2);
> > +
> > +     mutex_lock(base->mbox_mutex);
> > +
> > +     ret =3D cdns_mhdp_mailbox_send(base, MB_MODULE_ID_DP_TX,
> > +                                  DPTX_WRITE_REGISTER,
> sizeof(msg),
> msg);
> > +
> > +     mutex_unlock(base->mbox_mutex);
> > +
> > +     return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(cdns_mhdp_dp_reg_write);
> > +
> > +int cdns_mhdp_dp_reg_write_bit(struct cdns_mhdp_base *base, u16 addr,
> > +                            u8 start_bit, u8 bits_no, u32 val) {
> > +     u8 field[8];
> > +     int ret;
> > +
> > +     put_unaligned_be16(addr, field);
> > +     field[2] =3D start_bit;
> > +     field[3] =3D bits_no;
> > +     put_unaligned_be32(val, field + 4);
> > +
> > +     mutex_lock(base->mbox_mutex);
> > +
> > +     ret =3D cdns_mhdp_mailbox_send(base, MB_MODULE_ID_DP_TX,
> > +                                  DPTX_WRITE_FIELD,
> sizeof(field),
> field);
> > +
> > +     mutex_unlock(base->mbox_mutex);
> > +
> > +     return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(cdns_mhdp_dp_reg_write_bit);
> > +
> > +int cdns_mhdp_dpcd_read(struct cdns_mhdp_base *base,
> > +                     u32 addr, u8 *data, u16 len) {
> > +     u8 msg[5], reg[5];
> > +     int ret;
> > +
> > +     put_unaligned_be16(len, msg);
> > +     put_unaligned_be24(addr, msg + 2);
> > +
> > +     mutex_lock(base->mbox_mutex);
> > +
> > +     ret =3D cdns_mhdp_mailbox_send(base, MB_MODULE_ID_DP_TX,
> > +                                  DPTX_READ_DPCD, sizeof(msg),
> msg);
> > +     if (ret)
> > +             goto out;
> > +
> > +     ret =3D cdns_mhdp_mailbox_recv_header(base,
> MB_MODULE_ID_DP_TX,
> > +                                         DPTX_READ_DPCD,
> > +                                         sizeof(reg) + len);
> > +     if (ret)
> > +             goto out;
> > +
> > +     ret =3D cdns_mhdp_mailbox_recv_data(base, reg, sizeof(reg));
> > +     if (ret)
> > +             goto out;
> > +
> > +     ret =3D cdns_mhdp_mailbox_recv_data(base, data, len);
> > +
> > +out:
> > +     mutex_unlock(base->mbox_mutex);
> > +
> > +     return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(cdns_mhdp_dpcd_read);
> > +
> > +int cdns_mhdp_dpcd_write(struct cdns_mhdp_base *base, u32 addr, u8
> > +value) {
> > +     u8 msg[6], reg[5];
> > +     int ret;
> > +
> > +     put_unaligned_be16(1, msg);
> > +     put_unaligned_be24(addr, msg + 2);
> > +     msg[5] =3D value;
> > +
> > +     mutex_lock(base->mbox_mutex);
> > +
> > +     ret =3D cdns_mhdp_mailbox_send(base, MB_MODULE_ID_DP_TX,
> > +                                  DPTX_WRITE_DPCD,
> sizeof(msg),
> msg);
> > +     if (ret)
> > +             goto out;
> > +
> > +     ret =3D cdns_mhdp_mailbox_recv_header(base,
> MB_MODULE_ID_DP_TX,
> > +                                         DPTX_WRITE_DPCD,
> sizeof(reg));
> > +     if (ret)
> > +             goto out;
> > +
> > +     ret =3D cdns_mhdp_mailbox_recv_data(base, reg, sizeof(reg));
> > +     if (ret)
> > +             goto out;
> > +
> > +     if (addr !=3D get_unaligned_be24(reg + 2))
> > +             ret =3D -EINVAL;
> > +
> > +out:
> > +     mutex_unlock(base->mbox_mutex);
> > +
> > +     if (ret)
> > +             dev_err(base->dev, "dpcd write failed: %d\n", ret);
> > +     return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(cdns_mhdp_dpcd_write);
> > +
> > +MODULE_DESCRIPTION("Cadence MHDP Helper driver");
> > +MODULE_AUTHOR("Sandor Yu <Sandor.yu@nxp.com>");
> > +MODULE_LICENSE("GPL");
> > [...]
> > diff --git a/include/drm/bridge/cdns-mhdp-helper.h
> > b/include/drm/bridge/cdns-mhdp-helper.h new file mode 100644 index
> > 0000000000000..b89db9e842266
> > --- /dev/null
> > +++ b/include/drm/bridge/cdns-mhdp-helper.h
> > @@ -0,0 +1,96 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * Copyright (C) 2023 NXP Semiconductor, Inc.
> > + */
> > +#ifndef __CDNS_MHDP_HELPER_H__
> > +#define __CDNS_MHDP_HELPER_H__
> > +
> > +#include <asm/unaligned.h>
> > +#include <linux/iopoll.h>
> > +
> > +/* mailbox regs offset */
> > +#define CDNS_MAILBOX_FULL                    0x00008
> > +#define CDNS_MAILBOX_EMPTY                   0x0000c
> > +#define CDNS_MAILBOX_TX_DATA                 0x00010
> > +#define CDNS_MAILBOX_RX_DATA                 0x00014
> > +
> > +#define MAILBOX_RETRY_US                     1000
> > +#define MAILBOX_TIMEOUT_US                   2000000
> > +
> > +/* Module ID Code */
> > +#define MB_MODULE_ID_DP_TX                   0x01
> > +#define MB_MODULE_ID_HDMI_TX                 0x03
> > +#define MB_MODULE_ID_HDCP_TX                 0x07
> > +#define MB_MODULE_ID_HDCP_RX                 0x08
> > +#define MB_MODULE_ID_HDCP_GENERAL            0x09
> > +#define MB_MODULE_ID_GENERAL                 0x0A
> > +
> > +/* General Commands */
> > +#define GENERAL_MAIN_CONTROL                 0x01
> > +#define GENERAL_TEST_ECHO                    0x02
> > +#define GENERAL_BUS_SETTINGS                 0x03
> > +#define GENERAL_TEST_ACCESS                  0x04
> > +#define GENERAL_REGISTER_WRITE                       0x05
> > +#define GENERAL_WRITE_FIELD                  0x06
> > +#define GENERAL_REGISTER_READ                        0x07
> > +#define GENERAL_GET_HPD_STATE                        0x11
> > +
> > +/* DPTX Commands */
> > +#define DPTX_SET_POWER_MNG                   0x00
> > +#define DPTX_SET_HOST_CAPABILITIES           0x01
> > +#define DPTX_GET_EDID                                0x02
> > +#define DPTX_READ_DPCD                               0x03
> > +#define DPTX_WRITE_DPCD                              0x04
> > +#define DPTX_ENABLE_EVENT                    0x05
> > +#define DPTX_WRITE_REGISTER                  0x06
> > +#define DPTX_READ_REGISTER                   0x07
> > +#define DPTX_WRITE_FIELD                     0x08
> > +#define DPTX_TRAINING_CONTROL                        0x09
> > +#define DPTX_READ_EVENT                              0x0a
> > +#define DPTX_READ_LINK_STAT                  0x0b
> > +#define DPTX_SET_VIDEO                               0x0c
> > +#define DPTX_SET_AUDIO                               0x0d
> > +#define DPTX_GET_LAST_AUX_STAUS                      0x0e
> > +#define DPTX_SET_LINK_BREAK_POINT            0x0f
> > +#define DPTX_FORCE_LANES                     0x10
> > +#define DPTX_HPD_STATE                               0x11
> > +#define DPTX_ADJUST_LT                               0x12
> > +
> > +/* HDMI TX Commands */
> > +#define HDMI_TX_READ                         0x00
> > +#define HDMI_TX_WRITE                                0x01
> > +#define HDMI_TX_UPDATE_READ                  0x02
> > +#define HDMI_TX_EDID                         0x03
> > +#define HDMI_TX_EVENTS                               0x04
> > +#define HDMI_TX_HPD_STATUS                   0x05
> > +
> > +struct cdns_mhdp_base {
> > +     struct device *dev;
> > +     void __iomem *regs;
> > +     /* protect mailbox communications with the firmware */
> > +     struct mutex *mbox_mutex;
> > +};
> > +
> > +/* Mailbox helper functions */
> > +int cdns_mhdp_mailbox_read(struct cdns_mhdp_base *base); int
> > +cdns_mhdp_mailbox_write(struct cdns_mhdp_base *base, u8 val);
>=20
> You can remove these two declarations.

cdns_mhdp_mailbox_read will be removed. Thanks!

B.R
Sandor

>=20
> Best regards,
> Alexander
>=20
> Best regards,
> > +int cdns_mhdp_mailbox_recv_header(struct cdns_mhdp_base *base,
> > +                               u8 module_id, u8 opcode, u16
> req_size);
> > +int cdns_mhdp_mailbox_recv_data(struct cdns_mhdp_base *base,
> > +                             u8 *buff, u16 buff_size); int
> > +cdns_mhdp_mailbox_send(struct cdns_mhdp_base *base, u8 module_id,
> > +                        u8 opcode, u16 size, u8 *message);
> > +
> > +/* General commands helper functions */ int cdns_mhdp_reg_read(struct
> > +cdns_mhdp_base *base, u32 addr, u32 *value); int
> > +cdns_mhdp_reg_write(struct cdns_mhdp_base *base, u32 addr, u32 val);
> > +
> > +/* DPTX commands helper functions */
> > +int cdns_mhdp_dp_reg_write(struct cdns_mhdp_base *base, u16 addr,
> u32
> > +val); int cdns_mhdp_dp_reg_write_bit(struct cdns_mhdp_base *base, u16
> > +addr, +
>=20
> >       u8 start_bit, u8 bits_no, u32 val);
> > +int cdns_mhdp_dpcd_read(struct cdns_mhdp_base *base,
> > +                     u32 addr, u8 *data, u16 len); int
> > +cdns_mhdp_dpcd_write(struct cdns_mhdp_base *base, u32 addr, u8
> > +value);
> > +
> > +#endif /* __CDNS_MHDP_HELPER_H__ */
>=20
> TQ-Systems GmbH | M=FChlstra=DFe 2, Gut Delling | 82229 Seefeld, Germany
> Amtsgericht M=FCnchen, HRB 105018
> Gesch=E4ftsf=FChrer: Detlef Schneider, R=FCdiger Stahl, Stefan Schneider
>=20
>=20