Hi Nikolaus,

Le mer., nov. 24 2021 at 17:13:30 +0100, H. Nikolaus Schaller 
[off-list ref] a écrit :

quoted

 Am 23.11.2021 um 21:05 schrieb Paul Cercueil [off-list ref]:

 Hi Nikolaus,

 I keep seeing a few things, sorry.

no problem.

quoted

 Le mar., nov. 23 2021 at 19:13:57 +0100, H. Nikolaus Schaller 
[off-list ref] a écrit :

quoted

 From: Paul Boddie [off-list ref]
 A specialisation of the generic Synopsys HDMI driver is employed 
for
 JZ4780 HDMI support. This requires a new driver, plus device tree 
and
 configuration modifications.
 Here we add Kconfig DRM_INGENIC_DW_HDMI, Makefile and driver code.
 Signed-off-by: Paul Boddie [off-list ref]
 Signed-off-by: Ezequiel Garcia [off-list ref]
 Signed-off-by: H. Nikolaus Schaller [off-list ref]
 ---
 drivers/gpu/drm/ingenic/Kconfig           |   9 ++
 drivers/gpu/drm/ingenic/Makefile          |   1 +
 drivers/gpu/drm/ingenic/ingenic-dw-hdmi.c | 129 
++++++++++++++++++++++
 3 files changed, 139 insertions(+)
 create mode 100644 drivers/gpu/drm/ingenic/ingenic-dw-hdmi.c
 diff --git a/drivers/gpu/drm/ingenic/Kconfig 
b/drivers/gpu/drm/ingenic/Kconfig
 index 3b57f8be007c4..4efc709d77b0a 100644
 --- a/drivers/gpu/drm/ingenic/Kconfig
 +++ b/drivers/gpu/drm/ingenic/Kconfig
 @@ -25,4 +25,13 @@ config DRM_INGENIC_IPU
 	  The Image Processing Unit (IPU) will appear as a second primary 
plane.
 +config DRM_INGENIC_DW_HDMI
 +	tristate "Ingenic specific support for Synopsys DW HDMI"
 +	depends on MACH_JZ4780
 +	select DRM_DW_HDMI
 +	help
 +	  Choose this option to enable Synopsys DesignWare HDMI based 
driver.
 +	  If you want to enable HDMI on Ingenic JZ4780 based SoC, you 
should
 +	  select this option..
 +
 endif
 diff --git a/drivers/gpu/drm/ingenic/Makefile 
b/drivers/gpu/drm/ingenic/Makefile
 index d313326bdddbb..f10cc1c5a5f22 100644
 --- a/drivers/gpu/drm/ingenic/Makefile
 +++ b/drivers/gpu/drm/ingenic/Makefile
 @@ -1,3 +1,4 @@
 obj-$(CONFIG_DRM_INGENIC) += ingenic-drm.o
 ingenic-drm-y = ingenic-drm-drv.o
 ingenic-drm-$(CONFIG_DRM_INGENIC_IPU) += ingenic-ipu.o
 +obj-$(CONFIG_DRM_INGENIC_DW_HDMI) += ingenic-dw-hdmi.o
 diff --git a/drivers/gpu/drm/ingenic/ingenic-dw-hdmi.c 
b/drivers/gpu/drm/ingenic/ingenic-dw-hdmi.c
 new file mode 100644
 index 0000000000000..c14890d6b9826
 --- /dev/null
 +++ b/drivers/gpu/drm/ingenic/ingenic-dw-hdmi.c
 @@ -0,0 +1,129 @@
 +// SPDX-License-Identifier: GPL-2.0
 +/* Copyright (C) 2011-2013 Freescale Semiconductor, Inc.
 + * Copyright (C) 2019, 2020 Paul Boddie [off-list ref]
 + *
 + * Derived from dw_hdmi-imx.c with i.MX portions removed.
 + * Probe and remove operations derived from rcar_dw_hdmi.c.
 + */
 +
 +#include <linux/module.h>
 +#include <linux/platform_device.h>
 +#include <linux/regmap.h>
 +
 +#include <drm/bridge/dw_hdmi.h>
 +#include <drm/drm_of.h>
 +#include <drm/drm_print.h>
 +
 +static const struct dw_hdmi_mpll_config ingenic_mpll_cfg[] = {
 +	{ 45250000,  { { 0x01e0, 0x0000 }, { 0x21e1, 0x0000 }, { 0x41e2, 
0x0000 } } },
 +	{ 92500000,  { { 0x0140, 0x0005 }, { 0x2141, 0x0005 }, { 0x4142, 
0x0005 } } },
 +	{ 148500000, { { 0x00a0, 0x000a }, { 0x20a1, 0x000a }, { 0x40a2, 
0x000a } } },
 +	{ 216000000, { { 0x00a0, 0x000a }, { 0x2001, 0x000f }, { 0x4002, 
0x000f } } },
 +	{ ~0UL,      { { 0x0000, 0x0000 }, { 0x0000, 0x0000 }, { 0x0000, 
0x0000 } } }
 +};
 +
 +static const struct dw_hdmi_curr_ctrl ingenic_cur_ctr[] = {
 +	/*pixelclk     bpp8    bpp10   bpp12 */
 +	{ 54000000,  { 0x091c, 0x091c, 0x06dc } },
 +	{ 58400000,  { 0x091c, 0x06dc, 0x06dc } },
 +	{ 72000000,  { 0x06dc, 0x06dc, 0x091c } },
 +	{ 74250000,  { 0x06dc, 0x0b5c, 0x091c } },
 +	{ 118800000, { 0x091c, 0x091c, 0x06dc } },
 +	{ 216000000, { 0x06dc, 0x0b5c, 0x091c } },
 +	{ ~0UL,      { 0x0000, 0x0000, 0x0000 } },
 +};
 +
 +/*
 + * Resistance term 133Ohm Cfg
 + * PREEMP config 0.00
 + * TX/CK level 10
 + */
 +static const struct dw_hdmi_phy_config ingenic_phy_config[] = {
 +	/*pixelclk   symbol   term   vlev */
 +	{ 216000000, 0x800d, 0x0005, 0x01ad},
 +	{ ~0UL,      0x0000, 0x0000, 0x0000}
 +};
 +
 +static enum drm_mode_status
 +ingenic_dw_hdmi_mode_valid(struct dw_hdmi *hdmi, void *data,
 +			   const struct drm_display_info *info,
 +			   const struct drm_display_mode *mode)
 +{
 +	if (mode->clock < 13500)
 +		return MODE_CLOCK_LOW;
 +	/* FIXME: Hardware is capable of 270MHz, but setup data is 
missing. */
 +	if (mode->clock > 216000)
 +		return MODE_CLOCK_HIGH;
 +
 +	return MODE_OK;
 +}
 +
 +static struct dw_hdmi_plat_data ingenic_dw_hdmi_plat_data = {
 +	.mpll_cfg   = ingenic_mpll_cfg,
 +	.cur_ctr    = ingenic_cur_ctr,
 +	.phy_config = ingenic_phy_config,
 +	.mode_valid = ingenic_dw_hdmi_mode_valid,
 +	.output_port	= 1,
 +};
 +
 +static const struct of_device_id ingenic_dw_hdmi_dt_ids[] = {
 +	{ .compatible = "ingenic,jz4780-dw-hdmi" },
 +	{ /* Sentinel */ },
 +};
 +MODULE_DEVICE_TABLE(of, ingenic_dw_hdmi_dt_ids);
 +
 +static int ingenic_dw_hdmi_probe(struct platform_device *pdev)
 +{
 +	struct dw_hdmi *hdmi;
 +	struct regulator *regulator;
 +	int ret;
 +
 +	hdmi = dw_hdmi_probe(pdev, &ingenic_dw_hdmi_plat_data);
 +	if (IS_ERR(hdmi))
 +		return PTR_ERR(hdmi);
 +
 +	platform_set_drvdata(pdev, hdmi);
 +
 +	regulator = devm_regulator_get_optional(&pdev->dev, "hdmi-5v");
 +

 Nit - you can remove this blank line.

ok.

quoted

quoted

 +	if (IS_ERR(regulator)) {
 +		ret = PTR_ERR(regulator);
 +
 +		DRM_DEV_ERROR(&pdev->dev, "failed to get hpd regulator: %s 
(%d)\n",
 +			      "hdmi-5v", ret);
 +		return ret;
 +	}
 +
 +	ret = regulator_enable(regulator);

 You used devm_regulator_get_optional(), so you are not guaranteed 
to obtain anything; your "regulator" variable might be a NULL 
pointer, so you can't just call regulator_enable() without checking 
it first.

right. I forgot about that.

quoted

quoted

 +	if (ret) {
 +		DRM_DEV_ERROR(&pdev->dev, "Failed to enable hpd regulator: 
%d\n",
 +			      ret);
 +		return ret;
 +	}
 +
 +	return 0;
 +}
 +
 +static int ingenic_dw_hdmi_remove(struct platform_device *pdev)
 +{
 +	struct dw_hdmi *hdmi = platform_get_drvdata(pdev);
 +
 +	dw_hdmi_remove(hdmi);

 You probably should disable the regulator (if not NULL) here.

Indeed. Would it be ok to make struct regulator *regulator static
or do we need dynamically allocated memory?

static non-const is almost always a bad idea, so avoid it.

You can either:

- create a "ingenic_dw_hdmi" struct that will contain a pointer to 
dw_hdmi and a pointer to the regulator. Instanciate it in the probe 
with devm_kzalloc() and set the pointers, then set it as the driver 
data (platform_set_drvdata). In the remove function you can then obtain 
the pointer to your ingenic_dw_hdmi struct with platform_get_drvdata(), 
and you can remove the dw_hdmi and unregister the regulator.

- register cleanup functions, using devm_add_action_or_reset(dev, f, 
priv). When it's time to cleanup, the kernel core will call f(priv) 
automatically. So you can add a small wrapper around dw_hdmi_remove() 
and another one around regulator_disable(), and those will be called 
automatically if your probe function fails, or when the driver is 
removed. Then you can completely remove the ".remove" callback. There 
are a few examples of these in the ingenic-drm-drv.c if you want to 
take a look.

Cheers,
-Paul

quoted

quoted

 +
 +	return 0;
 +}
 +
 +static struct platform_driver ingenic_dw_hdmi_driver = {
 +	.probe  = ingenic_dw_hdmi_probe,
 +	.remove = ingenic_dw_hdmi_remove,
 +	.driver = {
 +		.name = "dw-hdmi-ingenic",
 +		.of_match_table = ingenic_dw_hdmi_dt_ids,
 +	},
 +};
 +

 Nit - remove this blank line too.

ok.

quoted

 Cheers,
 -Paul

quoted

 +module_platform_driver(ingenic_dw_hdmi_driver);
 +
 +MODULE_DESCRIPTION("JZ4780 Specific DW-HDMI Driver Extension");
 +MODULE_LICENSE("GPL v2");
 +MODULE_ALIAS("platform:dwhdmi-ingenic");
 --
 2.33.0