[Intel-gfx] [RFC v2 3/4] drm/panel: Add new panel driver based on crystal cove pmic

[Kumar, Shobhit]

On 1/9/2015 6:38 PM, Jani Nikula wrote:
> On Fri, 02 Jan 2015, Shobhit Kumar <shobhit.kumar at intel.com> wrote:
>> This driver provides support for the "crystal_cove_panel" cell device.
>> On BYT-T pmic has to be used to enable/disable panel.
>
> This needs to be sent to dri-devel.

Will do for the updated patch after addressing all your comments.

>
> With the comments below addressed, and with the disclaimer that I have
> no idea about the pmic registers or required sleeps, this is
>
> Reviewed-by: Jani Nikula <jani.nikula at intel.com>
>
>>
>> Signed-off-by: Shobhit Kumar <shobhit.kumar at intel.com>
>> ---
>>   drivers/gpu/drm/panel/Kconfig             |   7 ++
>>   drivers/gpu/drm/panel/Makefile            |   1 +
>>   drivers/gpu/drm/panel/panel-crystalcove.c | 191 ++++++++++++++++++++++++++++++
>>   3 files changed, 199 insertions(+)
>>   create mode 100644 drivers/gpu/drm/panel/panel-crystalcove.c
>>
>> diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
>> index 024e98e..d813bd1 100644
>> --- a/drivers/gpu/drm/panel/Kconfig
>> +++ b/drivers/gpu/drm/panel/Kconfig
>> @@ -40,4 +40,11 @@ config DRM_PANEL_SHARP_LQ101R1SX01
>>   	  To compile this driver as a module, choose M here: the module
>>   	  will be called panel-sharp-lq101r1sx01.
>>
>> +config DRM_PANEL_CRYSTALCOVE
>> +	tristate "Crystalcove PMIC controlled panel"
>> +	depends on INTEL_SOC_PMIC
>
> INTEL_SOC_PMIC is still a bool (and requires I2C=y), and IMO should be
> fixed to support tristate. Or are there fundamental reasons this can't
> be done?

Jacob, can you answer this one for the PMIC driver. This has come up 
multiple times earlier also in some discussions.

>
>> +	help
>> +	  Say Y here if you want to enable support for DSI panel and backlight
>> +	  control using crystalcove pmic. This is used for BYT CR configurations
>> +
>>   endmenu
>> diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
>> index 4b2a043..c05824e 100644
>> --- a/drivers/gpu/drm/panel/Makefile
>> +++ b/drivers/gpu/drm/panel/Makefile
>> @@ -2,3 +2,4 @@ obj-$(CONFIG_DRM_PANEL_SIMPLE) += panel-simple.o
>>   obj-$(CONFIG_DRM_PANEL_LD9040) += panel-ld9040.o
>>   obj-$(CONFIG_DRM_PANEL_S6E8AA0) += panel-s6e8aa0.o
>>   obj-$(CONFIG_DRM_PANEL_SHARP_LQ101R1SX01) += panel-sharp-lq101r1sx01.o
>> +obj-$(CONFIG_DRM_PANEL_CRYSTALCOVE) += panel-crystalcove.o
>> diff --git a/drivers/gpu/drm/panel/panel-crystalcove.c b/drivers/gpu/drm/panel/panel-crystalcove.c
>> new file mode 100644
>> index 0000000..22f7ff5
>> --- /dev/null
>> +++ b/drivers/gpu/drm/panel/panel-crystalcove.c
>> @@ -0,0 +1,191 @@
>> +/*
>> + * Copyright © 2006-2014 Intel Corporation
>
> 2006?!
>
>> + *
>> + * Permission is hereby granted, free of charge, to any person obtaining a
>> + * copy of this software and associated documentation files (the "Software"),
>> + * to deal in the Software without restriction, including without limitation
>> + * the rights to use, copy, modify, merge, publish, distribute, sublicense,
>> + * and/or sell copies of the Software, and to permit persons to whom the
>> + * Software is furnished to do so, subject to the following conditions:
>> + *
>> + * The above copyright notice and this permission notice (including the next
>> + * paragraph) shall be included in all copies or substantial portions of the
>> + * Software.
>> + *
>> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
>> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
>> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
>> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
>> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
>> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
>> + * DEALINGS IN THE SOFTWARE.
>> + *
>> + * Authors:
>> + *	Shobhit Kumar <shobhit.kumar at intel.com>
>> + */
>> +
>> +#include <drm/drmP.h>
>> +#include <drm/drm_crtc.h>
>> +#include <drm/drm_panel.h>
>> +#include <linux/mfd/intel_soc_pmic.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/regmap.h>
>> +
>> +#define PMIC_PANEL_EN		0x52
>> +#define PMIC_PWM_EN		0x51
>> +#define PMIC_BKL_EN		0x4B
>> +#define PMIC_PWM_LEVEL		0x4E
>> +
>> +struct crystalcove_panel {
>> +	struct drm_panel base;
>> +	char name[NAME_MAX];
>
> Unused.
>
>> +	bool prepared;
>> +	bool enabled;
>> +
>> +	struct mutex lock;
>
> Unused.
>
>> +
>> +	/* crystal cove pmic regmap */
>> +	struct regmap *regmap;
>> +};
>> +
>> +static inline struct crystalcove_panel *to_crystalcove_panel(struct drm_panel *panel)
>> +{
>> +	return container_of(panel, struct crystalcove_panel, base);
>> +}
>> +
>> +static int crystalcove_panel_disable(struct drm_panel *panel)
>> +{
>> +	struct crystalcove_panel *p = to_crystalcove_panel(panel);
>> +
>> +	if (!p->enabled)
>> +		return 0;
>> +
>> +	DRM_DEBUG_KMS("\n");
>> +
>> +	/* invoke the pmic driver */
>> +	regmap_write(p->regmap, PMIC_PANEL_EN, 0x00);
>> +
>> +	/* Disable backlight as well */
>> +	regmap_write(p->regmap, PMIC_PWM_LEVEL, 0);
>> +	msleep(20);
>
> Seems like a long delay.
>
>> +	regmap_write(p->regmap, PMIC_PWM_EN, 0x00);
>> +	regmap_write(p->regmap, PMIC_BKL_EN, 0x7F);
>> +
>> +	p->enabled = false;
>> +
>> +	return 0;
>> +}
>> +
>> +static int crystalcove_panel_unprepare(struct drm_panel *panel)
>> +{
>> +	struct crystalcove_panel *p = to_crystalcove_panel(panel);
>> +
>> +	if (!p->prepared)
>> +		return 0;
>> +
>> +	/* Nothing needed */
>> +	p->prepared = false;
>> +
>> +	return 0;
>> +}
>> +
>> +static int crystalcove_panel_prepare(struct drm_panel *panel)
>> +{
>> +	struct crystalcove_panel *p = to_crystalcove_panel(panel);
>> +
>> +	if (p->prepared)
>> +		return 0;
>> +
>> +	/* Nothing needed */
>> +	p->prepared = true;
>> +
>> +	return 0;
>> +}
>
> If you don't need prepare/unprepare, you can just leave them out
> altogether. It's easy to add them if you need them later.
>
>> +
>> +static int crystalcove_panel_enable(struct drm_panel *panel)
>> +{
>> +	struct crystalcove_panel *p = to_crystalcove_panel(panel);
>> +
>> +	if (p->enabled)
>> +		return 0;
>> +
>> +	DRM_DEBUG_KMS("\n");
>> +
>> +	/* invoke the pmic driver */
>> +	regmap_write(p->regmap, PMIC_PANEL_EN, 0x01);
>> +
>> +	/* Enable BKL as well */
>> +	regmap_write(p->regmap, PMIC_BKL_EN, 0xFF);
>> +	regmap_write(p->regmap, PMIC_PWM_EN, 0x01);
>> +	msleep(20);
>> +	regmap_write(p->regmap, PMIC_PWM_LEVEL, 255);
>> +
>> +	p->enabled = true;
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct drm_panel_funcs crystalcove_panel_funcs = {
>> +	.disable = crystalcove_panel_disable,
>> +	.unprepare = crystalcove_panel_unprepare,
>> +	.prepare = crystalcove_panel_prepare,
>> +	.enable = crystalcove_panel_enable,
>> +};
>> +
>> +static int crystalcove_panel_probe(struct platform_device *pdev)
>> +{
>> +	struct crystalcove_panel *panel;
>> +	int retval;
>> +	struct device *dev = pdev->dev.parent;
>> +	struct intel_soc_pmic *pmic = dev_get_drvdata(dev);
>> +
>> +	panel = devm_kzalloc(&pdev->dev, sizeof(*panel), GFP_KERNEL);
>> +	if (!panel)
>> +		return -ENOMEM;
>> +
>> +	DRM_DEBUG_KMS("\n");
>> +
>> +	platform_set_drvdata(pdev, panel);
>> +
>> +	strcpy(panel->base.name, "crystal_cove_panel");
>> +	panel->regmap = pmic->regmap;
>> +
>> +	regmap_read(panel->regmap, PMIC_PANEL_EN, &retval);
>> +	panel->enabled = panel->prepared = retval ? true : false;
>
> For bools you can just assign retval, or if you want to emphasis it's a
> bool you can use !!retval.
>
>> +
>> +	drm_panel_init(&panel->base);
>> +	panel->base.dev = dev;
>> +	panel->base.funcs = &crystalcove_panel_funcs;
>> +
>> +	drm_panel_add(&panel->base);
>> +
>> +	return 0;
>> +}
>> +
>> +static int crystalcove_panel_remove(struct platform_device *pdev)
>> +{
>> +	struct crystalcove_panel *panel = platform_get_drvdata(pdev);
>> +
>> +	DRM_DEBUG_KMS("\n");
>> +
>> +	drm_panel_detach(&panel->base);
>> +	drm_panel_remove(&panel->base);
>> +
>> +	crystalcove_panel_disable(&panel->base);
>> +
>> +	return 0;
>> +}
>> +
>> +static struct platform_driver crystalcove_panel_driver = {
>> +	.probe = crystalcove_panel_probe,
>> +	.remove = crystalcove_panel_remove,
>> +	.driver = {
>> +		.name = "crystal_cove_panel",
>> +	},
>> +};
>> +
>> +module_platform_driver(crystalcove_panel_driver);
>> +
>> +MODULE_AUTHOR("Shobhit Kumar <shobhit.kumar at linux.intel.com");
>> +MODULE_DESCRIPTION("Intel Crystal Cove Panel Driver");
>> +MODULE_LICENSE("GPL v2");
>
> This conflicts with the copyright header of the file.
>
>
>> --
>> 1.9.1
>>
>