Subject: Re: [PATCH v5 2/2] drm/bridge: Add NWL MIPI DSI host controller support

From: Guido Günther <[email-masked]>
Date: Thu, 19 Sep 2019 10:43:13 -0700

Hi Andrzej,

thanks for your comments!

On Thu, Sep 19, 2019 at 03:56:45PM +0200, Andrzej Hajda wrote:
> On 14.09.2019 18:11, Guido Günther wrote:
> > Hi Andrzej,
> > thanks for having a look!
> >
> > On Fri, Sep 13, 2019 at 11:31:43AM +0200, Andrzej Hajda wrote:
> >> On 09.09.2019 04:25, Guido Günther wrote:
> >>> This adds initial support for the NWL MIPI DSI Host controller found on
> >>> i.MX8 SoCs.
> >>>
> >>> It adds support for the i.MX8MQ but the same IP can be found on
> >>> e.g. the i.MX8QXP.
> >>>
> >>> It has been tested on the Librem 5 devkit using mxsfb.
> >>>
> >>> Signed-off-by: Guido Günther <[email-masked]>
> >>> Co-developed-by: Robert Chiras <[email-masked]>
> >>> Signed-off-by: Robert Chiras <[email-masked]>
> >>> Tested-by: Robert Chiras <[email-masked]>
> >>> ---
> >>>  drivers/gpu/drm/bridge/Kconfig           |   2 +
> >>>  drivers/gpu/drm/bridge/Makefile          |   1 +
> >>>  drivers/gpu/drm/bridge/nwl-dsi/Kconfig   |  16 +
> >>>  drivers/gpu/drm/bridge/nwl-dsi/Makefile  |   4 +
> >>>  drivers/gpu/drm/bridge/nwl-dsi/nwl-drv.c | 499 ++++++++++++++++
> >>>  drivers/gpu/drm/bridge/nwl-dsi/nwl-drv.h |  65 +++
> >>>  drivers/gpu/drm/bridge/nwl-dsi/nwl-dsi.c | 696 +++++++++++++++++++++++
> >>>  drivers/gpu/drm/bridge/nwl-dsi/nwl-dsi.h | 112 ++++
> >>
> >> Why do you need separate files nwl-drv.[ch] and nwl-dsi.[ch] ? I guess
> >> you can merge all into one file, maybe with separate file for NWL
> >> register definitions.
> > Idea is to have driver setup, soc specific hooks and revision specific
> > quirks in one file and the dsi specific parts in another. If that
> > doesn't fly I can merge into one if that's a requirement.
> 
> 
> One file looks saner to me :), but more importantly it follows current
> practice.

O.k., I'll merge things for v6 then.

> 
> 
> >
> >>>  8 files changed, 1395 insertions(+)
> >>>  create mode 100644 drivers/gpu/drm/bridge/nwl-dsi/Kconfig
> >>>  create mode 100644 drivers/gpu/drm/bridge/nwl-dsi/Makefile
> >>>  create mode 100644 drivers/gpu/drm/bridge/nwl-dsi/nwl-drv.c
> >>>  create mode 100644 drivers/gpu/drm/bridge/nwl-dsi/nwl-drv.h
> >>>  create mode 100644 drivers/gpu/drm/bridge/nwl-dsi/nwl-dsi.c
> >>>  create mode 100644 drivers/gpu/drm/bridge/nwl-dsi/nwl-dsi.h
> >>>
> >>> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
> >>> index 1cc9f502c1f2..7980b5c2156f 100644
> >>> --- a/drivers/gpu/drm/bridge/Kconfig
> >>> +++ b/drivers/gpu/drm/bridge/Kconfig
> >>> @@ -154,6 +154,8 @@ source "drivers/gpu/drm/bridge/analogix/Kconfig"
> >>>  
> >>>  source "drivers/gpu/drm/bridge/adv7511/Kconfig"
> >>>  
> >>> +source "drivers/gpu/drm/bridge/nwl-dsi/Kconfig"
> >>> +
> >>>  source "drivers/gpu/drm/bridge/synopsys/Kconfig"
> >>>  
> >>>  endmenu
> >>> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
> >>> index 4934fcf5a6f8..d9f6c0f77592 100644
> >>> --- a/drivers/gpu/drm/bridge/Makefile
> >>> +++ b/drivers/gpu/drm/bridge/Makefile
> >>> @@ -16,4 +16,5 @@ obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix/
> >>>  obj-$(CONFIG_DRM_I2C_ADV7511) += adv7511/
> >>>  obj-$(CONFIG_DRM_TI_SN65DSI86) += ti-sn65dsi86.o
> >>>  obj-$(CONFIG_DRM_TI_TFP410) += ti-tfp410.o
> >>> +obj-$(CONFIG_DRM_NWL_MIPI_DSI) += nwl-dsi/
> >>>  obj-y += synopsys/
> >>> diff --git a/drivers/gpu/drm/bridge/nwl-dsi/Kconfig b/drivers/gpu/drm/bridge/nwl-dsi/Kconfig
> >>> new file mode 100644
> >>> index 000000000000..7fa678e3b5e2
> >>> --- /dev/null
> >>> +++ b/drivers/gpu/drm/bridge/nwl-dsi/Kconfig
> >>> @@ -0,0 +1,16 @@
> >>> +config DRM_NWL_MIPI_DSI
> >>> +	tristate "Northwest Logic MIPI DSI Host controller"
> >>> +	depends on DRM
> >>> +	depends on COMMON_CLK
> >>> +	depends on OF && HAS_IOMEM
> >>> +	select DRM_KMS_HELPER
> >>> +	select DRM_MIPI_DSI
> >>> +	select DRM_PANEL_BRIDGE
> >>> +	select GENERIC_PHY_MIPI_DPHY
> >>> +	select MFD_SYSCON
> >>> +	select MULTIPLEXER
> >>> +	select REGMAP_MMIO
> >>> +	help
> >>> +	  This enables the Northwest Logic MIPI DSI Host controller as
> >>> +	  for example found on NXP's i.MX8 Processors.
> >>> +
> >>> diff --git a/drivers/gpu/drm/bridge/nwl-dsi/Makefile b/drivers/gpu/drm/bridge/nwl-dsi/Makefile
> >>> new file mode 100644
> >>> index 000000000000..804baf2f1916
> >>> --- /dev/null
> >>> +++ b/drivers/gpu/drm/bridge/nwl-dsi/Makefile
> >>> @@ -0,0 +1,4 @@
> >>> +# SPDX-License-Identifier: GPL-2.0
> >>> +nwl-mipi-dsi-y := nwl-drv.o nwl-dsi.o
> >>> +obj-$(CONFIG_DRM_NWL_MIPI_DSI) += nwl-mipi-dsi.o
> >>> +header-test-y += nwl-drv.h nwl-dsi.h
> >>> diff --git a/drivers/gpu/drm/bridge/nwl-dsi/nwl-drv.c b/drivers/gpu/drm/bridge/nwl-dsi/nwl-drv.c
> >>> new file mode 100644
> >>> index 000000000000..9ff43d2de127
> >>> --- /dev/null
> >>> +++ b/drivers/gpu/drm/bridge/nwl-dsi/nwl-drv.c
> >>> @@ -0,0 +1,499 @@
> >>> +// SPDX-License-Identifier: GPL-2.0+
> >>> +/*
> >>> + * i.MX8 NWL MIPI DSI host driver
> >>> + *
> >>> + * Copyright (C) 2017 NXP
> >>> + * Copyright (C) 2019 Purism SPC
> >>> + */
> >>> +
> >>> +#include <linux/clk.h>
> >>> +#include <linux/irq.h>
> >>> +#include <linux/mfd/syscon.h>
> >>> +#include <linux/module.h>
> >>> +#include <linux/mux/consumer.h>
> >>> +#include <linux/of.h>
> >>> +#include <linux/of_platform.h>
> >>> +#include <linux/phy/phy.h>
> >>> +#include <linux/reset.h>
> >>> +#include <linux/regmap.h>
> >>
> >> Alphabetic order
> > Fixed for v6.
> >
> >>> +#include <linux/sys_soc.h>
> >>> +
> >>> +#include <drm/drm_atomic_helper.h>
> >>> +#include <drm/drm_of.h>
> >>> +#include <drm/drm_print.h>
> >>> +#include <drm/drm_probe_helper.h>
> >>> +
> >>> +#include "nwl-drv.h"
> >>> +#include "nwl-dsi.h"
> >>> +
> >>> +#define DRV_NAME "nwl-dsi"
> >>> +
> >>> +/* Possible platform specific clocks */
> >>> +#define NWL_DSI_CLK_CORE	"core"
> >>> +
> >>> +static const struct regmap_config nwl_dsi_regmap_config = {
> >>> +	.reg_bits = 16,
> >>> +	.val_bits = 32,
> >>> +	.reg_stride = 4,
> >>> +	.max_register = NWL_DSI_IRQ_MASK2,
> >>> +	.name = DRV_NAME,
> >>> +};
> >>
> >> What is the point in using regmap here, why not simple writel/readl.
> > For me
> >
> >     cat /sys/kernel/debug/regmap/30a00000.mipi_dsi-imx-nwl-dsi/registers
> >
> > justifies it's use to help debugging problems when e.g. having it
> > connected to panels I don't own, so I think it's worth keeping if
> > possible.
> 
> 
> It still sounds for me like a sledgehammer to crack a nut, but it seems
> for many developers it is OK, so up to you.
> 
> 
> >
> >>> +
> >>> +struct nwl_dsi_platform_data {
> >>> +	int (*poweron)(struct nwl_dsi *dsi);
> >>> +	int (*poweroff)(struct nwl_dsi *dsi);
> >>> +	int (*select_input)(struct nwl_dsi *dsi);
> >>> +	int (*deselect_input)(struct nwl_dsi *dsi);
> >>> +	struct nwl_dsi_plat_clk_config clk_config[NWL_DSI_MAX_PLATFORM_CLOCKS];
> >>> +};
> >>
> >> Another construct which do not have justification, at least for now.
> >> Please simplify the driver, remove callbacks/intermediate
> >> structs/quirks
> >>
> >> - for now they are useless.
> >>
> >> Unless there is a serious reason - in such case please describe it in
> >> comments.
> > They're needed for i.mx 8QM SoC support (the current driver only
> > supports the i.mx 8MQ). It will be relatively easy to add with
> > these so I expect these to show up quickly. I'll add a comment. 
> 
> 
> That does not work well, it is impossible to review such code without
> looking at it's usage.
> 
> It would be better either to add 8QM driver in the same patchset showing
> the value of these callbacks, either remove them and add later together
> with 8QM driver.
> 
> Maybe these callbacks are not needed at all, but without 8QM code it is
> hard to decide.

I agree that it's hard to plan in advance until patches show up but let
me try to make a last argument for keeping them:

- The dsi select into imx8mq_dsi_select_input was suggested by Laurent
  since they're imx8 specific
- This would only leave poweron/off which is different between imx8mq
  and imx8qm:

  https://source.codeaurora.org/external/imx/linux-imx/tree/drivers/gpu/drm/imx/nwl_dsi-imx.c?h=imx_4.14.78_1.0.0_ga#n419

if that's still not worth it, i can drop them making the driver smaller.

> Btw. naming different SoCs 8QM an 8MQ suggests i.mx engineers are quite
> nasty :)

It sure is.

> > The quirks on the other hand only apply to some i.mx8MQ mask revisions
> > so they need to be conditionalized. (or maybe I misunderstood you).
> 
> 
> I guess at the moment the driver is tested only on one platform - you
> have not tested platforms with different set of quirks, am I correct?

I have tested with two silicon mask revisions where one needs the quirks
and the other doesn't and it behaved as intended.

> If so, the quirk 'infrastructure' is not really tested, driver just
> anticipates other 8MQ SoCs/platforms. Practice shows that it does not
> work well - adding support for different revision usually require either
> more changes either no changes at all, so this pre-mature
> "diversification" serves nothing except unnecessary noise.

Does the above make the diversification o.k.?

> >>> +
> >>> +static inline struct nwl_dsi *bridge_to_dsi(struct drm_bridge *bridge)
> >>> +{
> >>> +	return container_of(bridge, struct nwl_dsi, bridge);
> >>> +}
> >>> +
> >>> +static int nwl_dsi_set_platform_clocks(struct nwl_dsi *dsi, bool enable)
> >>> +{
> >>> +	struct device *dev = dsi->dev;
> >>> +	const char *id;
> >>> +	struct clk *clk;
> >>> +	size_t i;
> >>> +	unsigned long rate;
> >>> +	int ret, result = 0;
> >>> +
> >>> +	DRM_DEV_DEBUG_DRIVER(dev, "%s platform clocks\n",
> >>> +			     enable ? "enabling" : "disabling");
> >>> +	for (i = 0; i < ARRAY_SIZE(dsi->pdata->clk_config); i++) {
> >>> +		if (!dsi->clk_config[i].present)
> >>> +			continue;
> >>> +		id = dsi->clk_config[i].id;
> >>> +		clk = dsi->clk_config[i].clk;
> >>> +
> >>> +		if (enable) {
> >>> +			ret = clk_prepare_enable(clk);
> >>> +			if (ret < 0) {
> >>> +				DRM_DEV_ERROR(dev,
> >>> +					      "Failed to enable %s clk: %d\n",
> >>> +					      id, ret);
> >>> +				result = result ?: ret;
> >>> +			}
> >>> +			rate = clk_get_rate(clk);
> >>> +			DRM_DEV_DEBUG_DRIVER(dev, "Enabled %s clk @%lu Hz\n",
> >>> +					     id, rate);
> >>> +		} else {
> >>> +			clk_disable_unprepare(clk);
> >>> +			DRM_DEV_DEBUG_DRIVER(dev, "Disabled %s clk\n", id);
> >>> +		}
> >>> +	}
> >>> +
> >>> +	return result;
> >>> +}
> >>> +
> >>> +static int nwl_dsi_plat_enable(struct nwl_dsi *dsi)
> >>> +{
> >>> +	struct device *dev = dsi->dev;
> >>> +	int ret;
> >>> +
> >>> +	if (dsi->pdata->select_input)
> >>> +		dsi->pdata->select_input(dsi);
> >>> +
> >>> +	ret = nwl_dsi_set_platform_clocks(dsi, true);
> >>> +	if (ret < 0)
> >>> +		return ret;
> >>> +
> >>> +	ret = dsi->pdata->poweron(dsi);
> >>> +	if (ret < 0)
> >>> +		DRM_DEV_ERROR(dev, "Failed to power on DSI: %d\n", ret);
> >>> +	return ret;
> >>> +}
> >>> +
> >>> +static void nwl_dsi_plat_disable(struct nwl_dsi *dsi)
> >>> +{
> >>> +	dsi->pdata->poweroff(dsi);
> >>> +	nwl_dsi_set_platform_clocks(dsi, false);
> >>> +	if (dsi->pdata->deselect_input)
> >>> +		dsi->pdata->deselect_input(dsi);
> >>> +}
> >>> +
> >>> +static void nwl_dsi_bridge_disable(struct drm_bridge *bridge)
> >>> +{
> >>> +	struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> >>> +
> >>> +	nwl_dsi_disable(dsi);
> >>> +	nwl_dsi_plat_disable(dsi);
> >>> +	pm_runtime_put(dsi->dev);
> >>> +}
> >>> +
> >>> +static int nwl_dsi_get_dphy_params(struct nwl_dsi *dsi,
> >>> +				   const struct drm_display_mode *mode,
> >>> +				   union phy_configure_opts *phy_opts)
> >>> +{
> >>> +	unsigned long rate;
> >>> +	int ret;
> >>> +
> >>> +	if (dsi->lanes < 1 || dsi->lanes > 4)
> >>> +		return -EINVAL;
> >>> +
> >>> +	/*
> >>> +	 * So far the DPHY spec minimal timings work for both mixel
> >>> +	 * dphy and nwl dsi host
> >>> +	 */
> >>> +	ret = phy_mipi_dphy_get_default_config(
> >>> +		mode->crtc_clock * 1000,
> >>> +		mipi_dsi_pixel_format_to_bpp(dsi->format), dsi->lanes,
> >>> +		&phy_opts->mipi_dphy);
> >>> +	if (ret < 0)
> >>> +		return ret;
> >>> +
> >>> +	rate = clk_get_rate(dsi->tx_esc_clk);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "LP clk is @%lu Hz\n", rate);
> >>> +	phy_opts->mipi_dphy.lp_clk_rate = rate;
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static bool nwl_dsi_bridge_mode_fixup(struct drm_bridge *bridge,
> >>> +				      const struct drm_display_mode *mode,
> >>> +				      struct drm_display_mode *adjusted_mode)
> >>> +{
> >>> +	/* At least LCDIF + NWL needs active high sync */
> >>> +	adjusted_mode->flags |= (DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC);
> >>> +	adjusted_mode->flags &= ~(DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC);
> >>> +
> >>> +	return true;
> >>> +}
> >>> +
> >>> +static enum drm_mode_status
> >>> +nwl_dsi_bridge_mode_valid(struct drm_bridge *bridge,
> >>> +			  const struct drm_display_mode *mode)
> >>> +{
> >>> +	struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> >>> +	int bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> >>> +
> >>> +	if (mode->clock * bpp > 15000000 * dsi->lanes)
> >>> +		return MODE_CLOCK_HIGH;
> >>> +
> >>> +	if (mode->clock * bpp < 80000 * dsi->lanes)
> >>> +		return MODE_CLOCK_LOW;
> >>> +
> >>> +	return MODE_OK;
> >>> +}
> >>> +
> >>> +static void
> >>> +nwl_dsi_bridge_mode_set(struct drm_bridge *bridge,
> >>> +			const struct drm_display_mode *mode,
> >>> +			const struct drm_display_mode *adjusted_mode)
> >>> +{
> >>> +	struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> >>> +	struct device *dev = dsi->dev;
> >>> +	union phy_configure_opts new_cfg;
> >>> +	unsigned long phy_ref_rate;
> >>> +	int ret;
> >>> +
> >>> +	ret = nwl_dsi_get_dphy_params(dsi, adjusted_mode, &new_cfg);
> >>> +	if (ret < 0)
> >>> +		return;
> >>> +
> >>> +	/*
> >>> +	 * If hs clock is unchanged, we're all good - all parameters are
> >>> +	 * derived from it atm.
> >>> +	 */
> >>> +	if (new_cfg.mipi_dphy.hs_clk_rate == dsi->phy_cfg.mipi_dphy.hs_clk_rate)
> >>> +		return;
> >>> +
> >>> +	phy_ref_rate = clk_get_rate(dsi->phy_ref_clk);
> >>> +	DRM_DEV_DEBUG_DRIVER(dev, "PHY at ref rate: %lu\n", phy_ref_rate);
> >>> +	/* Save the new desired phy config */
> >>> +	memcpy(&dsi->phy_cfg, &new_cfg, sizeof(new_cfg));
> >>> +
> >>> +	memcpy(&dsi->mode, adjusted_mode, sizeof(dsi->mode));
> >>> +	drm_mode_debug_printmodeline(adjusted_mode);
> >>> +}
> >>> +
> >>> +static void nwl_dsi_bridge_pre_enable(struct drm_bridge *bridge)
> >>> +{
> >>> +	struct nwl_dsi *dsi = bridge_to_dsi(bridge);
> >>> +
> >>> +	pm_runtime_get_sync(dsi->dev);
> >>> +	nwl_dsi_plat_enable(dsi);
> >>> +	nwl_dsi_enable(dsi);
> >>> +}
> >>> +
> >>> +static int nwl_dsi_bridge_attach(struct drm_bridge *bridge)
> >>> +{
> >>> +	struct nwl_dsi *dsi = bridge->driver_private;
> >>> +
> >>> +	return drm_bridge_attach(bridge->encoder, dsi->panel_bridge, bridge);
> >>> +}
> >>> +
> >>> +static const struct drm_bridge_funcs nwl_dsi_bridge_funcs = {
> >>> +	.pre_enable = nwl_dsi_bridge_pre_enable,
> >>> +	.disable    = nwl_dsi_bridge_disable,
> >>> +	.mode_fixup = nwl_dsi_bridge_mode_fixup,
> >>> +	.mode_set   = nwl_dsi_bridge_mode_set,
> >>> +	.mode_valid = nwl_dsi_bridge_mode_valid,
> >>> +	.attach	    = nwl_dsi_bridge_attach,
> >>> +};
> >>> +
> >>> +static int nwl_dsi_parse_dt(struct nwl_dsi *dsi)
> >>> +{
> >>> +	struct platform_device *pdev = to_platform_device(dsi->dev);
> >>> +	struct clk *clk;
> >>> +	const char *clk_id;
> >>> +	void __iomem *base;
> >>> +	int i, ret;
> >>> +
> >>> +	dsi->phy = devm_phy_get(dsi->dev, "dphy");
> >>> +	if (IS_ERR(dsi->phy)) {
> >>> +		ret = PTR_ERR(dsi->phy);
> >>> +		if (ret != -EPROBE_DEFER)
> >>> +			DRM_DEV_ERROR(dsi->dev, "Could not get PHY: %d\n", ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	/* Platform dependent clocks */
> >>> +	memcpy(dsi->clk_config, dsi->pdata->clk_config,
> >>> +	       sizeof(dsi->pdata->clk_config));
> >>> +
> >>> +	for (i = 0; i < ARRAY_SIZE(dsi->pdata->clk_config); i++) {
> >>> +		if (!dsi->clk_config[i].present)
> >>> +			continue;
> >>> +
> >>> +		clk_id = dsi->clk_config[i].id;
> >>> +		clk = devm_clk_get(dsi->dev, clk_id);
> >>> +		if (IS_ERR(clk)) {
> >>> +			ret = PTR_ERR(clk);
> >>> +			DRM_DEV_ERROR(dsi->dev, "Failed to get %s clock: %d\n",
> >>> +				      clk_id, ret);
> >>> +			return ret;
> >>> +		}
> >>> +		DRM_DEV_DEBUG_DRIVER(dsi->dev, "Setup clk %s (rate: %lu)\n",
> >>> +				     clk_id, clk_get_rate(clk));
> >>> +		dsi->clk_config[i].clk = clk;
> >>> +	}
> >>> +
> >>> +	/* DSI clocks */
> >>> +	clk = devm_clk_get(dsi->dev, "phy_ref");
> >>> +	if (IS_ERR(clk)) {
> >>> +		ret = PTR_ERR(clk);
> >>> +		DRM_DEV_ERROR(dsi->dev, "Failed to get phy_ref clock: %d\n",
> >>> +			      ret);
> >>> +		return ret;
> >>> +	}
> >>> +	dsi->phy_ref_clk = clk;
> >>> +
> >>> +	clk = devm_clk_get(dsi->dev, "rx_esc");
> >>> +	if (IS_ERR(clk)) {
> >>> +		ret = PTR_ERR(clk);
> >>> +		DRM_DEV_ERROR(dsi->dev, "Failed to get rx_esc clock: %d\n",
> >>> +			      ret);
> >>> +		return ret;
> >>> +	}
> >>> +	dsi->rx_esc_clk = clk;
> >>> +
> >>> +	clk = devm_clk_get(dsi->dev, "tx_esc");
> >>> +	if (IS_ERR(clk)) {
> >>> +		ret = PTR_ERR(clk);
> >>> +		DRM_DEV_ERROR(dsi->dev, "Failed to get tx_esc clock: %d\n",
> >>> +			      ret);
> >>> +		return ret;
> >>> +	}
> >>> +	dsi->tx_esc_clk = clk;
> >>> +
> >>> +	dsi->mux = devm_mux_control_get(dsi->dev, NULL);
> >>> +	if (IS_ERR(dsi->mux)) {
> >>> +		ret = PTR_ERR(dsi->mux);
> >>> +		if (ret != -EPROBE_DEFER)
> >>> +			DRM_DEV_ERROR(dsi->dev, "Failed to get mux: %d\n", ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	base = devm_platform_ioremap_resource(pdev, 0);
> >>> +	if (IS_ERR(base))
> >>> +		return PTR_ERR(base);
> >>> +
> >>> +	dsi->regmap =
> >>> +		devm_regmap_init_mmio(dsi->dev, base, &nwl_dsi_regmap_config);
> >>> +	if (IS_ERR(dsi->regmap)) {
> >>> +		ret = PTR_ERR(dsi->regmap);
> >>> +		DRM_DEV_ERROR(dsi->dev, "Failed to create NWL DSI regmap: %d\n",
> >>> +			      ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	dsi->irq = platform_get_irq(pdev, 0);
> >>> +	if (dsi->irq < 0) {
> >>> +		DRM_DEV_ERROR(dsi->dev, "Failed to get device IRQ: %d\n",
> >>> +			      dsi->irq);
> >>> +		return dsi->irq;
> >>> +	}
> >>> +
> >>> +	dsi->rstc = devm_reset_control_array_get(dsi->dev, false, true);
> >>> +	if (IS_ERR(dsi->rstc)) {
> >>> +		DRM_DEV_ERROR(dsi->dev, "Failed to get resets: %ld\n",
> >>> +			      PTR_ERR(dsi->rstc));
> >>> +		return PTR_ERR(dsi->rstc);
> >>> +	}
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int imx8mq_dsi_select_input(struct nwl_dsi *dsi)
> >>> +{
> >>> +	struct device_node *remote;
> >>> +	u32 use_dcss = 1;
> >>> +	int ret;
> >>> +
> >>> +	remote = of_graph_get_remote_node(dsi->dev->of_node, 0, 0);
> >>> +	if (strcmp(remote->name, "lcdif") == 0)
> >>> +		use_dcss = 0;
> >>
> >> Relying on node name seems to me wrong. I am not sure if whole logic for
> >> input select should be here.
> >>
> >> My 1st impression is that selecting should be done rather in DCSS or
> >> LCDIF driver, why do you want to put it here?
> > Doing it in here keeps it at a single location where on the other hand
> > it would need to be done in mxsfb (which handles other SoCs as well) and
> > upcoming dcss. Also we can have in the dsi enable path which e.g. mxsfb
> > doesn't even know about at this point.
> 
> 
> But as I understand mux is not a part of this IP. It is always
> problematic what to do with such small pieces of hw.
> 
> Let's keep it here until someone find better solution.
> 
> Btw do you have public tree for testing platforms with this driver, I am
> curious about this mux device.

https://source.puri.sm/guido.gunther/linux-imx8/blob/forward-upstream/next-20190823/mxsfb+nwl/v4/arch/arm64/boot/dts/freescale/imx8mq.dtsi#L477

it was prompted by

https://lists.freedesktop.org/archives/dri-devel/2019-August/230868.html

Cheers and thanks again for your comments,
 -- Guido

> 
> 
> Regards
> 
> Andrzej
> 
> 
> >
> > Cheers,
> >  -- Guido
> >
> >> Regards
> >>
> >> Andrzej
> >>
> >>
> >>> +
> >>> +	DRM_DEV_INFO(dsi->dev, "Using %s as input source\n",
> >>> +		     (use_dcss) ? "DCSS" : "LCDIF");
> >>> +
> >>> +	ret = mux_control_try_select(dsi->mux, use_dcss);
> >>> +	if (ret < 0)
> >>> +		DRM_DEV_ERROR(dsi->dev, "Failed to select input: %d\n", ret);
> >>> +
> >>> +	of_node_put(remote);
> >>> +	return ret;
> >>> +}
> >>> +
> >>> +
> >>> +static int imx8mq_dsi_deselect_input(struct nwl_dsi *dsi)
> >>> +{
> >>> +	int ret;
> >>> +
> >>> +	ret = mux_control_deselect(dsi->mux);
> >>> +	if (ret < 0)
> >>> +		DRM_DEV_ERROR(dsi->dev, "Failed to deselect input: %d\n", ret);
> >>> +
> >>> +	return ret;
> >>> +}
> >>> +
> >>> +
> >>> +static int imx8mq_dsi_poweron(struct nwl_dsi *dsi)
> >>> +{
> >>> +	int ret = 0;
> >>> +
> >>> +	/* otherwise the display stays blank */
> >>> +	usleep_range(200, 300);
> >>> +
> >>> +	if (dsi->rstc)
> >>> +		ret = reset_control_deassert(dsi->rstc);
> >>> +
> >>> +	return ret;
> >>> +}
> >>> +
> >>> +static int imx8mq_dsi_poweroff(struct nwl_dsi *dsi)
> >>> +{
> >>> +	int ret = 0;
> >>> +
> >>> +	if (dsi->quirks & SRC_RESET_QUIRK)
> >>> +		return 0;
> >>> +
> >>> +	if (dsi->rstc)
> >>> +		ret = reset_control_assert(dsi->rstc);
> >>> +	return ret;
> >>> +}
> >>> +
> >>> +static const struct drm_bridge_timings nwl_dsi_timings = {
> >>> +	.input_bus_flags = DRM_BUS_FLAG_DE_LOW,
> >>> +};
> >>> +
> >>> +static const struct nwl_dsi_platform_data imx8mq_dev = {
> >>> +	.poweron = &imx8mq_dsi_poweron,
> >>> +	.poweroff = &imx8mq_dsi_poweroff,
> >>> +	.select_input = &imx8mq_dsi_select_input,
> >>> +	.deselect_input = &imx8mq_dsi_deselect_input,
> >>> +	.clk_config = {
> >>> +		{ .id = NWL_DSI_CLK_CORE, .present = true },
> >>> +	},
> >>> +};
> >>> +
> >>> +static const struct of_device_id nwl_dsi_dt_ids[] = {
> >>> +	{ .compatible = "fsl,imx8mq-nwl-dsi", .data = &imx8mq_dev, },
> >>> +	{ /* sentinel */ }
> >>> +};
> >>> +MODULE_DEVICE_TABLE(of, nwl_dsi_dt_ids);
> >>> +
> >>> +static const struct soc_device_attribute nwl_dsi_quirks_match[] = {
> >>> +	{ .soc_id = "i.MX8MQ", .revision = "2.0",
> >>> +	  .data = (void *)(E11418_HS_MODE_QUIRK | SRC_RESET_QUIRK) },
> >>> +	{ /* sentinel. */ },
> >>> +};
> >>> +
> >>> +static int nwl_dsi_probe(struct platform_device *pdev)
> >>> +{
> >>> +	struct device *dev = &pdev->dev;
> >>> +	const struct of_device_id *of_id = of_match_device(nwl_dsi_dt_ids, dev);
> >>> +	const struct nwl_dsi_platform_data *pdata = of_id->data;
> >>> +	const struct soc_device_attribute *attr;
> >>> +	struct nwl_dsi *dsi;
> >>> +	int ret;
> >>> +
> >>> +	dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
> >>> +	if (!dsi)
> >>> +		return -ENOMEM;
> >>> +
> >>> +	dsi->dev = dev;
> >>> +	dsi->pdata = pdata;
> >>> +
> >>> +	ret = nwl_dsi_parse_dt(dsi);
> >>> +	if (ret)
> >>> +		return ret;
> >>> +
> >>> +	ret = devm_request_irq(dev, dsi->irq, nwl_dsi_irq_handler, 0,
> >>> +			       dev_name(dev), dsi);
> >>> +	if (ret < 0) {
> >>> +		DRM_DEV_ERROR(dev, "Failed to request IRQ %d: %d\n", dsi->irq,
> >>> +			      ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	dsi->dsi_host.ops = &nwl_dsi_host_ops;
> >>> +	dsi->dsi_host.dev = dev;
> >>> +	ret = mipi_dsi_host_register(&dsi->dsi_host);
> >>> +	if (ret) {
> >>> +		DRM_DEV_ERROR(dev, "Failed to register MIPI host: %d\n", ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	attr = soc_device_match(nwl_dsi_quirks_match);
> >>> +	if (attr)
> >>> +		dsi->quirks = (uintptr_t)attr->data;
> >>> +
> >>> +	dsi->bridge.driver_private = dsi;
> >>> +	dsi->bridge.funcs = &nwl_dsi_bridge_funcs;
> >>> +	dsi->bridge.of_node = dev->of_node;
> >>> +	dsi->bridge.timings = &nwl_dsi_timings;
> >>> +
> >>> +	dev_set_drvdata(dev, dsi);
> >>> +	pm_runtime_enable(dev);
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int nwl_dsi_remove(struct platform_device *pdev)
> >>> +{
> >>> +	struct nwl_dsi *dsi = platform_get_drvdata(pdev);
> >>> +
> >>> +	mipi_dsi_host_unregister(&dsi->dsi_host);
> >>> +	pm_runtime_disable(&pdev->dev);
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static struct platform_driver nwl_dsi_driver = {
> >>> +	.probe		= nwl_dsi_probe,
> >>> +	.remove		= nwl_dsi_remove,
> >>> +	.driver		= {
> >>> +		.of_match_table = nwl_dsi_dt_ids,
> >>> +		.name	= DRV_NAME,
> >>> +	},
> >>> +};
> >>> +
> >>> +module_platform_driver(nwl_dsi_driver);
> >>> +
> >>> +MODULE_AUTHOR("NXP Semiconductor");
> >>> +MODULE_AUTHOR("Purism SPC");
> >>> +MODULE_DESCRIPTION("Northwest Logic MIPI-DSI driver");
> >>> +MODULE_LICENSE("GPL"); /* GPLv2 or later */
> >>> diff --git a/drivers/gpu/drm/bridge/nwl-dsi/nwl-drv.h b/drivers/gpu/drm/bridge/nwl-dsi/nwl-drv.h
> >>> new file mode 100644
> >>> index 000000000000..1e72a9221401
> >>> --- /dev/null
> >>> +++ b/drivers/gpu/drm/bridge/nwl-dsi/nwl-drv.h
> >>> @@ -0,0 +1,65 @@
> >>> +/* SPDX-License-Identifier: GPL-2.0+ */
> >>> +/*
> >>> + * NWL MIPI DSI host driver
> >>> + *
> >>> + * Copyright (C) 2017 NXP
> >>> + * Copyright (C) 2019 Purism SPC
> >>> + */
> >>> +
> >>> +#ifndef __NWL_DRV_H__
> >>> +#define __NWL_DRV_H__
> >>> +
> >>> +#include <linux/mux/consumer.h>
> >>> +#include <linux/phy/phy.h>
> >>> +
> >>> +#include <drm/drm_bridge.h>
> >>> +#include <drm/drm_mipi_dsi.h>
> >>> +
> >>> +struct nwl_dsi_platform_data;
> >>> +
> >>> +/* i.MX8 NWL quirks */
> >>> +/* i.MX8MQ errata E11418 */
> >>> +#define E11418_HS_MODE_QUIRK	    BIT(0)
> >>> +/* Skip DSI bits in SRC on disable to avoid blank display on enable */
> >>> +#define SRC_RESET_QUIRK		    BIT(1)
> >>> +
> >>> +#define NWL_DSI_MAX_PLATFORM_CLOCKS 1
> >>> +struct nwl_dsi_plat_clk_config {
> >>> +	const char *id;
> >>> +	struct clk *clk;
> >>> +	bool present;
> >>> +};
> >>> +
> >>> +struct nwl_dsi {
> >>> +	struct drm_bridge bridge;
> >>> +	struct mipi_dsi_host dsi_host;
> >>> +	struct drm_bridge *panel_bridge;
> >>> +	struct device *dev;
> >>> +	struct phy *phy;
> >>> +	union phy_configure_opts phy_cfg;
> >>> +	unsigned int quirks;
> >>> +
> >>> +	struct regmap *regmap;
> >>> +	int irq;
> >>> +	struct reset_control *rstc;
> >>> +	struct mux_control *mux;
> >>> +
> >>> +	/* DSI clocks */
> >>> +	struct clk *phy_ref_clk;
> >>> +	struct clk *rx_esc_clk;
> >>> +	struct clk *tx_esc_clk;
> >>> +	/* Platform dependent clocks */
> >>> +	struct nwl_dsi_plat_clk_config clk_config[NWL_DSI_MAX_PLATFORM_CLOCKS];
> >>> +
> >>> +	/* dsi lanes */
> >>> +	u32 lanes;
> >>> +	enum mipi_dsi_pixel_format format;
> >>> +	struct drm_display_mode mode;
> >>> +	unsigned long dsi_mode_flags;
> >>> +
> >>> +	struct nwl_dsi_transfer *xfer;
> >>> +
> >>> +	const struct nwl_dsi_platform_data *pdata;
> >>> +};
> >>> +
> >>> +#endif /* __NWL_DRV_H__ */
> >>> diff --git a/drivers/gpu/drm/bridge/nwl-dsi/nwl-dsi.c b/drivers/gpu/drm/bridge/nwl-dsi/nwl-dsi.c
> >>> new file mode 100644
> >>> index 000000000000..e6038cb4e849
> >>> --- /dev/null
> >>> +++ b/drivers/gpu/drm/bridge/nwl-dsi/nwl-dsi.c
> >>> @@ -0,0 +1,696 @@
> >>> +// SPDX-License-Identifier: GPL-2.0+
> >>> +/*
> >>> + * NWL MIPI DSI host driver
> >>> + *
> >>> + * Copyright (C) 2017 NXP
> >>> + * Copyright (C) 2019 Purism SPC
> >>> + */
> >>> +
> >>> +#include <linux/bitfield.h>
> >>> +#include <linux/clk.h>
> >>> +#include <linux/irq.h>
> >>> +#include <linux/math64.h>
> >>> +#include <linux/regmap.h>
> >>> +#include <linux/time64.h>
> >>> +
> >>> +#include <video/mipi_display.h>
> >>> +#include <video/videomode.h>
> >>> +
> >>> +#include <drm/drm_atomic_helper.h>
> >>> +#include <drm/drm_crtc_helper.h>
> >>> +#include <drm/drm_of.h>
> >>> +#include <drm/drm_panel.h>
> >>> +#include <drm/drm_print.h>
> >>> +
> >>> +#include "nwl-drv.h"
> >>> +#include "nwl-dsi.h"
> >>> +
> >>> +#define NWL_DSI_MIPI_FIFO_TIMEOUT msecs_to_jiffies(500)
> >>> +
> >>> +/*
> >>> + * PKT_CONTROL format:
> >>> + * [15: 0] - word count
> >>> + * [17:16] - virtual channel
> >>> + * [23:18] - data type
> >>> + * [24]	   - LP or HS select (0 - LP, 1 - HS)
> >>> + * [25]	   - perform BTA after packet is sent
> >>> + * [26]	   - perform BTA only, no packet tx
> >>> + */
> >>> +#define NWL_DSI_WC(x)		FIELD_PREP(GENMASK(15, 0), (x))
> >>> +#define NWL_DSI_TX_VC(x)	FIELD_PREP(GENMASK(17, 16), (x))
> >>> +#define NWL_DSI_TX_DT(x)	FIELD_PREP(GENMASK(23, 18), (x))
> >>> +#define NWL_DSI_HS_SEL(x)	FIELD_PREP(GENMASK(24, 24), (x))
> >>> +#define NWL_DSI_BTA_TX(x)	FIELD_PREP(GENMASK(25, 25), (x))
> >>> +#define NWL_DSI_BTA_NO_TX(x)	FIELD_PREP(GENMASK(26, 26), (x))
> >>> +
> >>> +/*
> >>> + * RX_PKT_HEADER format:
> >>> + * [15: 0] - word count
> >>> + * [21:16] - data type
> >>> + * [23:22] - virtual channel
> >>> + */
> >>> +#define NWL_DSI_RX_DT(x)	FIELD_GET(GENMASK(21, 16), (x))
> >>> +#define NWL_DSI_RX_VC(x)	FIELD_GET(GENMASK(23, 22), (x))
> >>> +
> >>> +/* DSI Video mode */
> >>> +#define NWL_DSI_VM_BURST_MODE_WITH_SYNC_PULSES		0
> >>> +#define NWL_DSI_VM_NON_BURST_MODE_WITH_SYNC_EVENTS	BIT(0)
> >>> +#define NWL_DSI_VM_BURST_MODE				BIT(1)
> >>> +
> >>> +/* * DPI color coding */
> >>> +#define NWL_DSI_DPI_16_BIT_565_PACKED	0
> >>> +#define NWL_DSI_DPI_16_BIT_565_ALIGNED	1
> >>> +#define NWL_DSI_DPI_16_BIT_565_SHIFTED	2
> >>> +#define NWL_DSI_DPI_18_BIT_PACKED	3
> >>> +#define NWL_DSI_DPI_18_BIT_ALIGNED	4
> >>> +#define NWL_DSI_DPI_24_BIT		5
> >>> +
> >>> +/* * DPI Pixel format */
> >>> +#define NWL_DSI_PIXEL_FORMAT_16  0
> >>> +#define NWL_DSI_PIXEL_FORMAT_18  BIT(0)
> >>> +#define NWL_DSI_PIXEL_FORMAT_18L BIT(1)
> >>> +#define NWL_DSI_PIXEL_FORMAT_24  (BIT(0) | BIT(1))
> >>> +
> >>> +enum transfer_direction {
> >>> +	DSI_PACKET_SEND,
> >>> +	DSI_PACKET_RECEIVE,
> >>> +};
> >>> +
> >>> +struct nwl_dsi_transfer {
> >>> +	const struct mipi_dsi_msg *msg;
> >>> +	struct mipi_dsi_packet packet;
> >>> +	struct completion completed;
> >>> +
> >>> +	int status; /* status of transmission */
> >>> +	enum transfer_direction direction;
> >>> +	bool need_bta;
> >>> +	u8 cmd;
> >>> +	u16 rx_word_count;
> >>> +	size_t tx_len; /* in bytes */
> >>> +	size_t rx_len; /* in bytes */
> >>> +};
> >>> +
> >>> +static int nwl_dsi_write(struct nwl_dsi *dsi, unsigned int reg, u32 val)
> >>> +{
> >>> +	int ret;
> >>> +
> >>> +	ret = regmap_write(dsi->regmap, reg, val);
> >>> +	if (ret < 0)
> >>> +		DRM_DEV_ERROR(dsi->dev,
> >>> +			      "Failed to write NWL DSI reg 0x%x: %d\n", reg,
> >>> +			      ret);
> >>> +	return ret;
> >>> +}
> >>> +
> >>> +static u32 nwl_dsi_read(struct nwl_dsi *dsi, u32 reg)
> >>> +{
> >>> +	unsigned int val;
> >>> +	int ret;
> >>> +
> >>> +	ret = regmap_read(dsi->regmap, reg, &val);
> >>> +	if (ret < 0)
> >>> +		DRM_DEV_ERROR(dsi->dev, "Failed to read NWL DSI reg 0x%x: %d\n",
> >>> +			      reg, ret);
> >>> +
> >>> +	return val;
> >>> +}
> >>> +
> >>> +static u32 nwl_dsi_get_dpi_pixel_format(enum mipi_dsi_pixel_format format)
> >>> +{
> >>> +	switch (format) {
> >>> +	case MIPI_DSI_FMT_RGB565:
> >>> +		return NWL_DSI_PIXEL_FORMAT_16;
> >>> +	case MIPI_DSI_FMT_RGB666:
> >>> +		return NWL_DSI_PIXEL_FORMAT_18L;
> >>> +	case MIPI_DSI_FMT_RGB666_PACKED:
> >>> +		return NWL_DSI_PIXEL_FORMAT_18;
> >>> +	case MIPI_DSI_FMT_RGB888:
> >>> +		return NWL_DSI_PIXEL_FORMAT_24;
> >>> +	default:
> >>> +		return -EINVAL;
> >>> +	}
> >>> +}
> >>> +
> >>> +/*
> >>> + * ps2bc - Picoseconds to byte clock cycles
> >>> + */
> >>> +static u32 ps2bc(struct nwl_dsi *dsi, unsigned long long ps)
> >>> +{
> >>> +	u32 bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> >>> +
> >>> +	return DIV64_U64_ROUND_UP(ps * dsi->mode.clock * bpp,
> >>> +				  dsi->lanes * 8 * NSEC_PER_SEC);
> >>> +}
> >>> +
> >>> +/*
> >>> + * ui2bc - UI time periods to byte clock cycles
> >>> + */
> >>> +static u32 ui2bc(struct nwl_dsi *dsi, unsigned long long ui)
> >>> +{
> >>> +	u32 bpp = mipi_dsi_pixel_format_to_bpp(dsi->format);
> >>> +
> >>> +	return DIV64_U64_ROUND_UP(ui * dsi->lanes,
> >>> +				  dsi->mode.clock * 1000 * bpp);
> >>> +}
> >>> +
> >>> +/*
> >>> + * us2bc - micro seconds to lp clock cycles
> >>> + */
> >>> +static u32 us2lp(u32 lp_clk_rate, unsigned long us)
> >>> +{
> >>> +	return DIV_ROUND_UP(us * lp_clk_rate, USEC_PER_SEC);
> >>> +}
> >>> +
> >>> +static int nwl_dsi_config_host(struct nwl_dsi *dsi)
> >>> +{
> >>> +	u32 cycles;
> >>> +	struct phy_configure_opts_mipi_dphy *cfg = &dsi->phy_cfg.mipi_dphy;
> >>> +
> >>> +	if (dsi->lanes < 1 || dsi->lanes > 4)
> >>> +		return -EINVAL;
> >>> +
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "DSI Lanes %d\n", dsi->lanes);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_CFG_NUM_LANES, dsi->lanes - 1);
> >>> +
> >>> +	if (dsi->dsi_mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) {
> >>> +		nwl_dsi_write(dsi, NWL_DSI_CFG_NONCONTINUOUS_CLK, 0x01);
> >>> +		nwl_dsi_write(dsi, NWL_DSI_CFG_AUTOINSERT_EOTP, 0x01);
> >>> +	} else {
> >>> +		nwl_dsi_write(dsi, NWL_DSI_CFG_NONCONTINUOUS_CLK, 0x00);
> >>> +		nwl_dsi_write(dsi, NWL_DSI_CFG_AUTOINSERT_EOTP, 0x00);
> >>> +	}
> >>> +
> >>> +	/* values in byte clock cycles */
> >>> +	cycles = ui2bc(dsi, cfg->clk_pre);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_t_pre: 0x%x\n", cycles);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_CFG_T_PRE, cycles);
> >>> +	cycles = ps2bc(dsi, cfg->lpx + cfg->clk_prepare + cfg->clk_zero);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_tx_gap (pre): 0x%x\n", cycles);
> >>> +	cycles += ui2bc(dsi, cfg->clk_pre);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_t_post: 0x%x\n", cycles);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_CFG_T_POST, cycles);
> >>> +	cycles = ps2bc(dsi, cfg->hs_exit);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_tx_gap: 0x%x\n", cycles);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_CFG_TX_GAP, cycles);
> >>> +
> >>> +	nwl_dsi_write(dsi, NWL_DSI_CFG_EXTRA_CMDS_AFTER_EOTP, 0x01);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_CFG_HTX_TO_COUNT, 0x00);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_CFG_LRX_H_TO_COUNT, 0x00);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_CFG_BTA_H_TO_COUNT, 0x00);
> >>> +	/* In LP clock cycles */
> >>> +	cycles = us2lp(cfg->lp_clk_rate, cfg->wakeup);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "cfg_twakeup: 0x%x\n", cycles);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_CFG_TWAKEUP, cycles);
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int nwl_dsi_config_dpi(struct nwl_dsi *dsi)
> >>> +{
> >>> +	u32 color_format, mode;
> >>> +	bool burst_mode;
> >>> +	int hfront_porch, hback_porch, vfront_porch, vback_porch;
> >>> +	int hsync_len, vsync_len;
> >>> +
> >>> +	hfront_porch = dsi->mode.hsync_start - dsi->mode.hdisplay;
> >>> +	hsync_len = dsi->mode.hsync_end - dsi->mode.hsync_start;
> >>> +	hback_porch = dsi->mode.htotal - dsi->mode.hsync_end;
> >>> +
> >>> +	vfront_porch = dsi->mode.vsync_start - dsi->mode.vdisplay;
> >>> +	vsync_len = dsi->mode.vsync_end - dsi->mode.vsync_start;
> >>> +	vback_porch = dsi->mode.vtotal - dsi->mode.vsync_end;
> >>> +
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "hfront_porch = %d\n", hfront_porch);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "hback_porch = %d\n", hback_porch);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "hsync_len = %d\n", hsync_len);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "hdisplay = %d\n", dsi->mode.hdisplay);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "vfront_porch = %d\n", vfront_porch);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "vback_porch = %d\n", vback_porch);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "vsync_len = %d\n", vsync_len);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "vactive = %d\n", dsi->mode.vdisplay);
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "clock = %d kHz\n", dsi->mode.clock);
> >>> +
> >>> +	color_format = nwl_dsi_get_dpi_pixel_format(dsi->format);
> >>> +	if (color_format < 0) {
> >>> +		DRM_DEV_ERROR(dsi->dev, "Invalid color format 0x%x\n",
> >>> +			      dsi->format);
> >>> +		return color_format;
> >>> +	}
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "pixel fmt = %d\n", dsi->format);
> >>> +
> >>> +	nwl_dsi_write(dsi, NWL_DSI_INTERFACE_COLOR_CODING, NWL_DSI_DPI_24_BIT);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_PIXEL_FORMAT, color_format);
> >>> +	/*
> >>> +	 * Adjusting input polarity based on the video mode results in
> >>> +	 * a black screen so always pick active low:
> >>> +	 */
> >>> +	nwl_dsi_write(dsi, NWL_DSI_VSYNC_POLARITY,
> >>> +		      NWL_DSI_VSYNC_POLARITY_ACTIVE_LOW);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_HSYNC_POLARITY,
> >>> +		      NWL_DSI_HSYNC_POLARITY_ACTIVE_LOW);
> >>> +
> >>> +	burst_mode = (dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_BURST) &&
> >>> +		     !(dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE);
> >>> +
> >>> +	if (burst_mode) {
> >>> +		nwl_dsi_write(dsi, NWL_DSI_VIDEO_MODE, NWL_DSI_VM_BURST_MODE);
> >>> +		nwl_dsi_write(dsi, NWL_DSI_PIXEL_FIFO_SEND_LEVEL, 256);
> >>> +	} else {
> >>> +		mode = ((dsi->dsi_mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE) ?
> >>> +				NWL_DSI_VM_BURST_MODE_WITH_SYNC_PULSES :
> >>> +				NWL_DSI_VM_NON_BURST_MODE_WITH_SYNC_EVENTS);
> >>> +		nwl_dsi_write(dsi, NWL_DSI_VIDEO_MODE, mode);
> >>> +		nwl_dsi_write(dsi, NWL_DSI_PIXEL_FIFO_SEND_LEVEL,
> >>> +			      dsi->mode.hdisplay);
> >>> +	}
> >>> +
> >>> +	nwl_dsi_write(dsi, NWL_DSI_HFP, hfront_porch);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_HBP, hback_porch);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_HSA, hsync_len);
> >>> +
> >>> +	nwl_dsi_write(dsi, NWL_DSI_ENABLE_MULT_PKTS, 0x0);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_BLLP_MODE, 0x1);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_USE_NULL_PKT_BLLP, 0x0);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_VC, 0x0);
> >>> +
> >>> +	nwl_dsi_write(dsi, NWL_DSI_PIXEL_PAYLOAD_SIZE, dsi->mode.hdisplay);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_VACTIVE, dsi->mode.vdisplay - 1);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_VBP, vback_porch);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_VFP, vfront_porch);
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static void nwl_dsi_init_interrupts(struct nwl_dsi *dsi)
> >>> +{
> >>> +	u32 irq_enable;
> >>> +
> >>> +	nwl_dsi_write(dsi, NWL_DSI_IRQ_MASK, 0xffffffff);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_IRQ_MASK2, 0x7);
> >>> +
> >>> +	irq_enable = ~(u32)(NWL_DSI_TX_PKT_DONE_MASK |
> >>> +			    NWL_DSI_RX_PKT_HDR_RCVD_MASK |
> >>> +			    NWL_DSI_TX_FIFO_OVFLW_MASK |
> >>> +			    NWL_DSI_HS_TX_TIMEOUT_MASK);
> >>> +
> >>> +	nwl_dsi_write(dsi, NWL_DSI_IRQ_MASK, irq_enable);
> >>> +}
> >>> +
> >>> +static int nwl_dsi_host_attach(struct mipi_dsi_host *dsi_host,
> >>> +			       struct mipi_dsi_device *device)
> >>> +{
> >>> +	struct nwl_dsi *dsi = container_of(dsi_host, struct nwl_dsi, dsi_host);
> >>> +	struct device *dev = dsi->dev;
> >>> +	struct drm_bridge *bridge;
> >>> +	struct drm_panel *panel;
> >>> +	int ret;
> >>> +
> >>> +	DRM_DEV_INFO(dev, "lanes=%u, format=0x%x flags=0x%lx\n", device->lanes,
> >>> +		     device->format, device->mode_flags);
> >>> +
> >>> +	if (device->lanes < 1 || device->lanes > 4)
> >>> +		return -EINVAL;
> >>> +
> >>> +	dsi->lanes = device->lanes;
> >>> +	dsi->format = device->format;
> >>> +	dsi->dsi_mode_flags = device->mode_flags;
> >>> +
> >>> +	ret = drm_of_find_panel_or_bridge(dsi->dev->of_node, 1, 0, &panel,
> >>> +					  &bridge);
> >>> +	if (ret)
> >>> +		return ret;
> >>> +
> >>> +	if (panel) {
> >>> +		bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_DSI);
> >>> +		if (IS_ERR(bridge))
> >>> +			return PTR_ERR(bridge);
> >>> +	}
> >>> +
> >>> +	dsi->panel_bridge = bridge;
> >>> +	drm_bridge_add(&dsi->bridge);
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static int nwl_dsi_host_detach(struct mipi_dsi_host *dsi_host,
> >>> +			       struct mipi_dsi_device *device)
> >>> +{
> >>> +	struct nwl_dsi *dsi = container_of(dsi_host, struct nwl_dsi, dsi_host);
> >>> +
> >>> +	drm_of_panel_bridge_remove(dsi->dev->of_node, 1, 0);
> >>> +	drm_bridge_remove(&dsi->bridge);
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static bool nwl_dsi_read_packet(struct nwl_dsi *dsi, u32 status)
> >>> +{
> >>> +	struct device *dev = dsi->dev;
> >>> +	struct nwl_dsi_transfer *xfer = dsi->xfer;
> >>> +	u8 *payload = xfer->msg->rx_buf;
> >>> +	u32 val;
> >>> +	u16 word_count;
> >>> +	u8 channel;
> >>> +	u8 data_type;
> >>> +
> >>> +	xfer->status = 0;
> >>> +
> >>> +	if (xfer->rx_word_count == 0) {
> >>> +		if (!(status & NWL_DSI_RX_PKT_HDR_RCVD))
> >>> +			return false;
> >>> +		/* Get the RX header and parse it */
> >>> +		val = nwl_dsi_read(dsi, NWL_DSI_RX_PKT_HEADER);
> >>> +		word_count = NWL_DSI_WC(val);
> >>> +		channel = NWL_DSI_RX_VC(val);
> >>> +		data_type = NWL_DSI_RX_DT(val);
> >>> +
> >>> +		if (channel != xfer->msg->channel) {
> >>> +			DRM_DEV_ERROR(dev,
> >>> +				      "[%02X] Channel mismatch (%u != %u)\n",
> >>> +				      xfer->cmd, channel, xfer->msg->channel);
> >>> +			return true;
> >>> +		}
> >>> +
> >>> +		switch (data_type) {
> >>> +		case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_2BYTE:
> >>> +			/* Fall through */
> >>> +		case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_2BYTE:
> >>> +			if (xfer->msg->rx_len > 1) {
> >>> +				/* read second byte */
> >>> +				payload[1] = word_count >> 8;
> >>> +				++xfer->rx_len;
> >>> +			}
> >>> +			/* Fall through */
> >>> +		case MIPI_DSI_RX_GENERIC_SHORT_READ_RESPONSE_1BYTE:
> >>> +			/* Fall through */
> >>> +		case MIPI_DSI_RX_DCS_SHORT_READ_RESPONSE_1BYTE:
> >>> +			if (xfer->msg->rx_len > 0) {
> >>> +				/* read first byte */
> >>> +				payload[0] = word_count & 0xff;
> >>> +				++xfer->rx_len;
> >>> +			}
> >>> +			xfer->status = xfer->rx_len;
> >>> +			return true;
> >>> +		case MIPI_DSI_RX_ACKNOWLEDGE_AND_ERROR_REPORT:
> >>> +			word_count &= 0xff;
> >>> +			DRM_DEV_ERROR(dev, "[%02X] DSI error report: 0x%02x\n",
> >>> +				      xfer->cmd, word_count);
> >>> +			xfer->status = -EPROTO;
> >>> +			return true;
> >>> +		}
> >>> +
> >>> +		if (word_count > xfer->msg->rx_len) {
> >>> +			DRM_DEV_ERROR(
> >>> +				dev,
> >>> +				"[%02X] Receive buffer too small: %zu (< %u)\n",
> >>> +				xfer->cmd, xfer->msg->rx_len, word_count);
> >>> +			return true;
> >>> +		}
> >>> +
> >>> +		xfer->rx_word_count = word_count;
> >>> +	} else {
> >>> +		/* Set word_count from previous header read */
> >>> +		word_count = xfer->rx_word_count;
> >>> +	}
> >>> +
> >>> +	/* If RX payload is not yet received, wait for it */
> >>> +	if (!(status & NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD))
> >>> +		return false;
> >>> +
> >>> +	/* Read the RX payload */
> >>> +	while (word_count >= 4) {
> >>> +		val = nwl_dsi_read(dsi, NWL_DSI_RX_PAYLOAD);
> >>> +		payload[0] = (val >> 0) & 0xff;
> >>> +		payload[1] = (val >> 8) & 0xff;
> >>> +		payload[2] = (val >> 16) & 0xff;
> >>> +		payload[3] = (val >> 24) & 0xff;
> >>> +		payload += 4;
> >>> +		xfer->rx_len += 4;
> >>> +		word_count -= 4;
> >>> +	}
> >>> +
> >>> +	if (word_count > 0) {
> >>> +		val = nwl_dsi_read(dsi, NWL_DSI_RX_PAYLOAD);
> >>> +		switch (word_count) {
> >>> +		case 3:
> >>> +			payload[2] = (val >> 16) & 0xff;
> >>> +			++xfer->rx_len;
> >>> +			/* Fall through */
> >>> +		case 2:
> >>> +			payload[1] = (val >> 8) & 0xff;
> >>> +			++xfer->rx_len;
> >>> +			/* Fall through */
> >>> +		case 1:
> >>> +			payload[0] = (val >> 0) & 0xff;
> >>> +			++xfer->rx_len;
> >>> +			break;
> >>> +		}
> >>> +	}
> >>> +
> >>> +	xfer->status = xfer->rx_len;
> >>> +
> >>> +	return true;
> >>> +}
> >>> +
> >>> +static void nwl_dsi_finish_transmission(struct nwl_dsi *dsi, u32 status)
> >>> +{
> >>> +	struct nwl_dsi_transfer *xfer = dsi->xfer;
> >>> +	bool end_packet = false;
> >>> +
> >>> +	if (!xfer)
> >>> +		return;
> >>> +
> >>> +	if (xfer->direction == DSI_PACKET_SEND &&
> >>> +	    status & NWL_DSI_TX_PKT_DONE) {
> >>> +		xfer->status = xfer->tx_len;
> >>> +		end_packet = true;
> >>> +	} else if (status & NWL_DSI_DPHY_DIRECTION &&
> >>> +		   ((status & (NWL_DSI_RX_PKT_HDR_RCVD |
> >>> +			       NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD)))) {
> >>> +		end_packet = nwl_dsi_read_packet(dsi, status);
> >>> +	}
> >>> +
> >>> +	if (end_packet)
> >>> +		complete(&xfer->completed);
> >>> +}
> >>> +
> >>> +static void nwl_dsi_begin_transmission(struct nwl_dsi *dsi)
> >>> +{
> >>> +	struct nwl_dsi_transfer *xfer = dsi->xfer;
> >>> +	struct mipi_dsi_packet *pkt = &xfer->packet;
> >>> +	const u8 *payload;
> >>> +	size_t length;
> >>> +	u16 word_count;
> >>> +	u8 hs_mode;
> >>> +	u32 val;
> >>> +	u32 hs_workaround = 0;
> >>> +
> >>> +	/* Send the payload, if any */
> >>> +	length = pkt->payload_length;
> >>> +	payload = pkt->payload;
> >>> +
> >>> +	while (length >= 4) {
> >>> +		val = *(u32 *)payload;
> >>> +		hs_workaround |= !(val & 0xFFFF00);
> >>> +		nwl_dsi_write(dsi, NWL_DSI_TX_PAYLOAD, val);
> >>> +		payload += 4;
> >>> +		length -= 4;
> >>> +	}
> >>> +	/* Send the rest of the payload */
> >>> +	val = 0;
> >>> +	switch (length) {
> >>> +	case 3:
> >>> +		val |= payload[2] << 16;
> >>> +		/* Fall through */
> >>> +	case 2:
> >>> +		val |= payload[1] << 8;
> >>> +		hs_workaround |= !(val & 0xFFFF00);
> >>> +		/* Fall through */
> >>> +	case 1:
> >>> +		val |= payload[0];
> >>> +		nwl_dsi_write(dsi, NWL_DSI_TX_PAYLOAD, val);
> >>> +		break;
> >>> +	}
> >>> +	xfer->tx_len = pkt->payload_length;
> >>> +
> >>> +	/*
> >>> +	 * Send the header
> >>> +	 * header[0] = Virtual Channel + Data Type
> >>> +	 * header[1] = Word Count LSB (LP) or first param (SP)
> >>> +	 * header[2] = Word Count MSB (LP) or second param (SP)
> >>> +	 */
> >>> +	word_count = pkt->header[1] | (pkt->header[2] << 8);
> >>> +	if (hs_workaround && (dsi->quirks & E11418_HS_MODE_QUIRK)) {
> >>> +		DRM_DEV_DEBUG_DRIVER(dsi->dev,
> >>> +				     "Using hs mode workaround for cmd 0x%x\n",
> >>> +				     xfer->cmd);
> >>> +		hs_mode = 1;
> >>> +	} else {
> >>> +		hs_mode = (xfer->msg->flags & MIPI_DSI_MSG_USE_LPM) ? 0 : 1;
> >>> +	}
> >>> +	val = NWL_DSI_WC(word_count) | NWL_DSI_TX_VC(xfer->msg->channel) |
> >>> +	      NWL_DSI_TX_DT(xfer->msg->type) | NWL_DSI_HS_SEL(hs_mode) |
> >>> +	      NWL_DSI_BTA_TX(xfer->need_bta);
> >>> +	nwl_dsi_write(dsi, NWL_DSI_PKT_CONTROL, val);
> >>> +
> >>> +	/* Send packet command */
> >>> +	nwl_dsi_write(dsi, NWL_DSI_SEND_PACKET, 0x1);
> >>> +}
> >>> +
> >>> +static ssize_t nwl_dsi_host_transfer(struct mipi_dsi_host *dsi_host,
> >>> +				     const struct mipi_dsi_msg *msg)
> >>> +{
> >>> +	struct nwl_dsi *dsi = container_of(dsi_host, struct nwl_dsi, dsi_host);
> >>> +	struct nwl_dsi_transfer xfer;
> >>> +	ssize_t ret = 0;
> >>> +
> >>> +	/* Create packet to be sent */
> >>> +	dsi->xfer = &xfer;
> >>> +	ret = mipi_dsi_create_packet(&xfer.packet, msg);
> >>> +	if (ret < 0) {
> >>> +		dsi->xfer = NULL;
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	if ((msg->type & MIPI_DSI_GENERIC_READ_REQUEST_0_PARAM ||
> >>> +	     msg->type & MIPI_DSI_GENERIC_READ_REQUEST_1_PARAM ||
> >>> +	     msg->type & MIPI_DSI_GENERIC_READ_REQUEST_2_PARAM ||
> >>> +	     msg->type & MIPI_DSI_DCS_READ) &&
> >>> +	    msg->rx_len > 0 && msg->rx_buf != NULL)
> >>> +		xfer.direction = DSI_PACKET_RECEIVE;
> >>> +	else
> >>> +		xfer.direction = DSI_PACKET_SEND;
> >>> +
> >>> +	xfer.need_bta = (xfer.direction == DSI_PACKET_RECEIVE);
> >>> +	xfer.need_bta |= (msg->flags & MIPI_DSI_MSG_REQ_ACK) ? 1 : 0;
> >>> +	xfer.msg = msg;
> >>> +	xfer.status = -ETIMEDOUT;
> >>> +	xfer.rx_word_count = 0;
> >>> +	xfer.rx_len = 0;
> >>> +	xfer.cmd = 0x00;
> >>> +	if (msg->tx_len > 0)
> >>> +		xfer.cmd = ((u8 *)(msg->tx_buf))[0];
> >>> +	init_completion(&xfer.completed);
> >>> +
> >>> +	ret = clk_prepare_enable(dsi->rx_esc_clk);
> >>> +	if (ret < 0) {
> >>> +		DRM_DEV_ERROR(dsi->dev, "Failed to enable rx_esc clk: %zd\n",
> >>> +			      ret);
> >>> +		return ret;
> >>> +	}
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "Enabled rx_esc clk @%lu Hz\n",
> >>> +			     clk_get_rate(dsi->rx_esc_clk));
> >>> +
> >>> +	/* Initiate the DSI packet transmision */
> >>> +	nwl_dsi_begin_transmission(dsi);
> >>> +
> >>> +	if (!wait_for_completion_timeout(&xfer.completed,
> >>> +					 NWL_DSI_MIPI_FIFO_TIMEOUT)) {
> >>> +		DRM_DEV_ERROR(dsi_host->dev, "[%02X] DSI transfer timed out\n",
> >>> +			      xfer.cmd);
> >>> +		ret = -ETIMEDOUT;
> >>> +	} else {
> >>> +		ret = xfer.status;
> >>> +	}
> >>> +
> >>> +	clk_disable_unprepare(dsi->rx_esc_clk);
> >>> +
> >>> +	return ret;
> >>> +}
> >>> +
> >>> +const struct mipi_dsi_host_ops nwl_dsi_host_ops = {
> >>> +	.attach = nwl_dsi_host_attach,
> >>> +	.detach = nwl_dsi_host_detach,
> >>> +	.transfer = nwl_dsi_host_transfer,
> >>> +};
> >>> +
> >>> +irqreturn_t nwl_dsi_irq_handler(int irq, void *data)
> >>> +{
> >>> +	u32 irq_status;
> >>> +	struct nwl_dsi *dsi = data;
> >>> +
> >>> +	irq_status = nwl_dsi_read(dsi, NWL_DSI_IRQ_STATUS);
> >>> +
> >>> +	if (irq_status & NWL_DSI_TX_FIFO_OVFLW)
> >>> +		DRM_DEV_ERROR_RATELIMITED(dsi->dev, "tx fifo overflow\n");
> >>> +
> >>> +	if (irq_status & NWL_DSI_HS_TX_TIMEOUT)
> >>> +		DRM_DEV_ERROR_RATELIMITED(dsi->dev, "HS tx timeout\n");
> >>> +
> >>> +	if (irq_status & NWL_DSI_TX_PKT_DONE ||
> >>> +	    irq_status & NWL_DSI_RX_PKT_HDR_RCVD ||
> >>> +	    irq_status & NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD)
> >>> +		nwl_dsi_finish_transmission(dsi, irq_status);
> >>> +
> >>> +	return IRQ_HANDLED;
> >>> +}
> >>> +
> >>> +int nwl_dsi_enable(struct nwl_dsi *dsi)
> >>> +{
> >>> +	struct device *dev = dsi->dev;
> >>> +	union phy_configure_opts *phy_cfg = &dsi->phy_cfg;
> >>> +	int ret;
> >>> +
> >>> +	if (!dsi->lanes) {
> >>> +		DRM_DEV_ERROR(dev, "Need DSI lanes: %d\n", dsi->lanes);
> >>> +		return -EINVAL;
> >>> +	}
> >>> +
> >>> +	ret = phy_init(dsi->phy);
> >>> +	if (ret < 0) {
> >>> +		DRM_DEV_ERROR(dev, "Failed to init DSI phy: %d\n", ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	ret = phy_configure(dsi->phy, phy_cfg);
> >>> +	if (ret < 0) {
> >>> +		DRM_DEV_ERROR(dev, "Failed to configure DSI phy: %d\n", ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	ret = clk_prepare_enable(dsi->tx_esc_clk);
> >>> +	if (ret < 0) {
> >>> +		DRM_DEV_ERROR(dsi->dev, "Failed to enable tx_esc clk: %d\n",
> >>> +			      ret);
> >>> +		return ret;
> >>> +	}
> >>> +	DRM_DEV_DEBUG_DRIVER(dsi->dev, "Enabled tx_esc clk @%lu Hz\n",
> >>> +			     clk_get_rate(dsi->tx_esc_clk));
> >>> +
> >>> +	ret = nwl_dsi_config_host(dsi);
> >>> +	if (ret < 0) {
> >>> +		DRM_DEV_ERROR(dev, "Failed to set up DSI: %d", ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	ret = nwl_dsi_config_dpi(dsi);
> >>> +	if (ret < 0) {
> >>> +		DRM_DEV_ERROR(dev, "Failed to set up DPI: %d", ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	ret = phy_power_on(dsi->phy);
> >>> +	if (ret < 0) {
> >>> +		DRM_DEV_ERROR(dev, "Failed to power on DPHY (%d)\n", ret);
> >>> +		return ret;
> >>> +	}
> >>> +
> >>> +	nwl_dsi_init_interrupts(dsi);
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +int nwl_dsi_disable(struct nwl_dsi *dsi)
> >>> +{
> >>> +	struct device *dev = dsi->dev;
> >>> +
> >>> +	DRM_DEV_DEBUG_DRIVER(dev, "Disabling clocks and phy\n");
> >>> +
> >>> +	phy_power_off(dsi->phy);
> >>> +	phy_exit(dsi->phy);
> >>> +
> >>> +	/* Disabling the clock before the phy breaks enabling dsi again */
> >>> +	clk_disable_unprepare(dsi->tx_esc_clk);
> >>> +
> >>> +	return 0;
> >>> +}
> >>> diff --git a/drivers/gpu/drm/bridge/nwl-dsi/nwl-dsi.h b/drivers/gpu/drm/bridge/nwl-dsi/nwl-dsi.h
> >>> new file mode 100644
> >>> index 000000000000..579b366de652
> >>> --- /dev/null
> >>> +++ b/drivers/gpu/drm/bridge/nwl-dsi/nwl-dsi.h
> >>> @@ -0,0 +1,112 @@
> >>> +/* SPDX-License-Identifier: GPL-2.0+ */
> >>> +/*
> >>> + * NWL MIPI DSI host driver
> >>> + *
> >>> + * Copyright (C) 2017 NXP
> >>> + * Copyright (C) 2019 Purism SPC
> >>> + */
> >>> +#ifndef __NWL_DSI_H__
> >>> +#define __NWL_DSI_H__
> >>> +
> >>> +#include <linux/irqreturn.h>
> >>> +
> >>> +#include <drm/drm_mipi_dsi.h>
> >>> +
> >>> +#include "nwl-drv.h"
> >>> +
> >>> +/* DSI HOST registers */
> >>> +#define NWL_DSI_CFG_NUM_LANES			0x0
> >>> +#define NWL_DSI_CFG_NONCONTINUOUS_CLK		0x4
> >>> +#define NWL_DSI_CFG_T_PRE			0x8
> >>> +#define NWL_DSI_CFG_T_POST			0xc
> >>> +#define NWL_DSI_CFG_TX_GAP			0x10
> >>> +#define NWL_DSI_CFG_AUTOINSERT_EOTP		0x14
> >>> +#define NWL_DSI_CFG_EXTRA_CMDS_AFTER_EOTP	0x18
> >>> +#define NWL_DSI_CFG_HTX_TO_COUNT		0x1c
> >>> +#define NWL_DSI_CFG_LRX_H_TO_COUNT		0x20
> >>> +#define NWL_DSI_CFG_BTA_H_TO_COUNT		0x24
> >>> +#define NWL_DSI_CFG_TWAKEUP			0x28
> >>> +#define NWL_DSI_CFG_STATUS_OUT			0x2c
> >>> +#define NWL_DSI_RX_ERROR_STATUS			0x30
> >>> +
> >>> +/* DSI DPI registers */
> >>> +#define NWL_DSI_PIXEL_PAYLOAD_SIZE		0x200
> >>> +#define NWL_DSI_PIXEL_FIFO_SEND_LEVEL		0x204
> >>> +#define NWL_DSI_INTERFACE_COLOR_CODING		0x208
> >>> +#define NWL_DSI_PIXEL_FORMAT			0x20c
> >>> +#define NWL_DSI_VSYNC_POLARITY			0x210
> >>> +#define NWL_DSI_VSYNC_POLARITY_ACTIVE_LOW	0
> >>> +#define NWL_DSI_VSYNC_POLARITY_ACTIVE_HIGH	BIT(1)
> >>> +
> >>> +#define NWL_DSI_HSYNC_POLARITY			0x214
> >>> +#define NWL_DSI_HSYNC_POLARITY_ACTIVE_LOW	0
> >>> +#define NWL_DSI_HSYNC_POLARITY_ACTIVE_HIGH	BIT(1)
> >>> +
> >>> +#define NWL_DSI_VIDEO_MODE			0x218
> >>> +#define NWL_DSI_HFP				0x21c
> >>> +#define NWL_DSI_HBP				0x220
> >>> +#define NWL_DSI_HSA				0x224
> >>> +#define NWL_DSI_ENABLE_MULT_PKTS		0x228
> >>> +#define NWL_DSI_VBP				0x22c
> >>> +#define NWL_DSI_VFP				0x230
> >>> +#define NWL_DSI_BLLP_MODE			0x234
> >>> +#define NWL_DSI_USE_NULL_PKT_BLLP		0x238
> >>> +#define NWL_DSI_VACTIVE				0x23c
> >>> +#define NWL_DSI_VC				0x240
> >>> +
> >>> +/* DSI APB PKT control */
> >>> +#define NWL_DSI_TX_PAYLOAD			0x280
> >>> +#define NWL_DSI_PKT_CONTROL			0x284
> >>> +#define NWL_DSI_SEND_PACKET			0x288
> >>> +#define NWL_DSI_PKT_STATUS			0x28c
> >>> +#define NWL_DSI_PKT_FIFO_WR_LEVEL		0x290
> >>> +#define NWL_DSI_PKT_FIFO_RD_LEVEL		0x294
> >>> +#define NWL_DSI_RX_PAYLOAD			0x298
> >>> +#define NWL_DSI_RX_PKT_HEADER			0x29c
> >>> +
> >>> +/* DSI IRQ handling */
> >>> +#define NWL_DSI_IRQ_STATUS			0x2a0
> >>> +#define NWL_DSI_SM_NOT_IDLE			BIT(0)
> >>> +#define NWL_DSI_TX_PKT_DONE			BIT(1)
> >>> +#define NWL_DSI_DPHY_DIRECTION			BIT(2)
> >>> +#define NWL_DSI_TX_FIFO_OVFLW			BIT(3)
> >>> +#define NWL_DSI_TX_FIFO_UDFLW			BIT(4)
> >>> +#define NWL_DSI_RX_FIFO_OVFLW			BIT(5)
> >>> +#define NWL_DSI_RX_FIFO_UDFLW			BIT(6)
> >>> +#define NWL_DSI_RX_PKT_HDR_RCVD			BIT(7)
> >>> +#define NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD	BIT(8)
> >>> +#define NWL_DSI_BTA_TIMEOUT			BIT(29)
> >>> +#define NWL_DSI_LP_RX_TIMEOUT			BIT(30)
> >>> +#define NWL_DSI_HS_TX_TIMEOUT			BIT(31)
> >>> +
> >>> +#define NWL_DSI_IRQ_STATUS2			0x2a4
> >>> +#define NWL_DSI_SINGLE_BIT_ECC_ERR		BIT(0)
> >>> +#define NWL_DSI_MULTI_BIT_ECC_ERR		BIT(1)
> >>> +#define NWL_DSI_CRC_ERR				BIT(2)
> >>> +
> >>> +#define NWL_DSI_IRQ_MASK			0x2a8
> >>> +#define NWL_DSI_SM_NOT_IDLE_MASK		BIT(0)
> >>> +#define NWL_DSI_TX_PKT_DONE_MASK		BIT(1)
> >>> +#define NWL_DSI_DPHY_DIRECTION_MASK		BIT(2)
> >>> +#define NWL_DSI_TX_FIFO_OVFLW_MASK		BIT(3)
> >>> +#define NWL_DSI_TX_FIFO_UDFLW_MASK		BIT(4)
> >>> +#define NWL_DSI_RX_FIFO_OVFLW_MASK		BIT(5)
> >>> +#define NWL_DSI_RX_FIFO_UDFLW_MASK		BIT(6)
> >>> +#define NWL_DSI_RX_PKT_HDR_RCVD_MASK		BIT(7)
> >>> +#define NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD_MASK	BIT(8)
> >>> +#define NWL_DSI_BTA_TIMEOUT_MASK		BIT(29)
> >>> +#define NWL_DSI_LP_RX_TIMEOUT_MASK		BIT(30)
> >>> +#define NWL_DSI_HS_TX_TIMEOUT_MASK		BIT(31)
> >>> +
> >>> +#define NWL_DSI_IRQ_MASK2			0x2ac
> >>> +#define NWL_DSI_SINGLE_BIT_ECC_ERR_MASK		BIT(0)
> >>> +#define NWL_DSI_MULTI_BIT_ECC_ERR_MASK		BIT(1)
> >>> +#define NWL_DSI_CRC_ERR_MASK			BIT(2)
> >>> +
> >>> +extern const struct mipi_dsi_host_ops nwl_dsi_host_ops;
> >>> +
> >>> +irqreturn_t nwl_dsi_irq_handler(int irq, void *data);
> >>> +int nwl_dsi_enable(struct nwl_dsi *dsi);
> >>> +int nwl_dsi_disable(struct nwl_dsi *dsi);
> >>> +
> >>> +#endif /* __NWL_DSI_H__ */
> >>
> >
> 

_______________________________________________
linux-arm-kernel mailing list
[email-masked]
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel