diff mbox

[v1,2/2] drm/tinydrm: add driver for ST7735R panels

Message ID 1511924469-11448-3-git-send-email-david@lechnology.com (mailing list archive)
State New, archived
Headers show

Commit Message

David Lechner Nov. 29, 2017, 3:01 a.m. UTC 
This adds a new driver for Sitronix ST7735R display panels.

This has been tested using an Adafruit 1.8" TFT.

Signed-off-by: David Lechner <david@lechnology.com>
---
 MAINTAINERS                       |   6 +
 drivers/gpu/drm/tinydrm/Kconfig   |  10 ++
 drivers/gpu/drm/tinydrm/Makefile  |   1 +
 drivers/gpu/drm/tinydrm/st7735r.c | 237 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 254 insertions(+)
 create mode 100644 drivers/gpu/drm/tinydrm/st7735r.c

Comments

Noralf Trønnes Dec. 6, 2017, 6:27 p.m. UTC | #1 
Den 29.11.2017 04.01, skrev David Lechner:
> This adds a new driver for Sitronix ST7735R display panels.
>
> This has been tested using an Adafruit 1.8" TFT.
>
> Signed-off-by: David Lechner <david@lechnology.com>
> ---
>   MAINTAINERS                       |   6 +
>   drivers/gpu/drm/tinydrm/Kconfig   |  10 ++
>   drivers/gpu/drm/tinydrm/Makefile  |   1 +
>   drivers/gpu/drm/tinydrm/st7735r.c | 237 ++++++++++++++++++++++++++++++++++++++
>   4 files changed, 254 insertions(+)
>   create mode 100644 drivers/gpu/drm/tinydrm/st7735r.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index a174632..9c7707e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4462,6 +4462,12 @@ S:	Maintained
>   F:	drivers/gpu/drm/tinydrm/st7586.c
>   F:	Documentation/devicetree/bindings/display/st7586.txt
>   
> +DRM DRIVER FOR SITRONIX ST7735R PANELS
> +M:	David Lechner <david@lechnology.com>

I know we haven't done this in the other tinydrm drivers, but I think
we should start adding which tree the development is happening in:

T:    git git://anongit.freedesktop.org/drm/drm-misc

> +S:	Maintained
> +F:	drivers/gpu/drm/tinydrm/st7735r.c
> +F:	Documentation/devicetree/bindings/display/st7735r.txt
> +
>   DRM DRIVER FOR TDFX VIDEO CARDS
>   S:	Orphan / Obsolete
>   F:	drivers/gpu/drm/tdfx/
> diff --git a/drivers/gpu/drm/tinydrm/Kconfig b/drivers/gpu/drm/tinydrm/Kconfig
> index 90c5bd5..b0e567d 100644
> --- a/drivers/gpu/drm/tinydrm/Kconfig
> +++ b/drivers/gpu/drm/tinydrm/Kconfig
> @@ -52,3 +52,13 @@ config TINYDRM_ST7586
>   	  * LEGO MINDSTORMS EV3
>   
>   	  If M is selected the module will be called st7586.
> +
> +config TINYDRM_ST7735R
> +	tristate "DRM support for Sitronix ST7735R display panels"
> +	depends on DRM_TINYDRM && SPI
> +	select TINYDRM_MIPI_DBI
> +	help
> +	  DRM driver Sitronix ST7735R with one of the following LCDs:
> +	  * JD-T18003-T01 1.8" 128x160 TFT
> +
> +	  If M is selected the module will be called st7735r.
> diff --git a/drivers/gpu/drm/tinydrm/Makefile b/drivers/gpu/drm/tinydrm/Makefile
> index 8aeee53..49a1119 100644
> --- a/drivers/gpu/drm/tinydrm/Makefile
> +++ b/drivers/gpu/drm/tinydrm/Makefile
> @@ -8,3 +8,4 @@ obj-$(CONFIG_TINYDRM_ILI9225)		+= ili9225.o
>   obj-$(CONFIG_TINYDRM_MI0283QT)		+= mi0283qt.o
>   obj-$(CONFIG_TINYDRM_REPAPER)		+= repaper.o
>   obj-$(CONFIG_TINYDRM_ST7586)		+= st7586.o
> +obj-$(CONFIG_TINYDRM_ST7735R)		+= st7735r.o
> diff --git a/drivers/gpu/drm/tinydrm/st7735r.c b/drivers/gpu/drm/tinydrm/st7735r.c
> new file mode 100644
> index 0000000..6435b00
> --- /dev/null
> +++ b/drivers/gpu/drm/tinydrm/st7735r.c
> @@ -0,0 +1,237 @@
> +/*
> + * DRM driver for Sitronix ST7735R panels
> + *
> + * Copyright 2017 David Lechner <david@lechnology.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/dma-buf.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/module.h>
> +#include <linux/property.h>
> +#include <linux/spi/spi.h>
> +#include <video/mipi_display.h>
> +
> +#include <drm/drm_gem_framebuffer_helper.h>
> +#include <drm/tinydrm/mipi-dbi.h>
> +#include <drm/tinydrm/tinydrm-helpers.h>
> +
> +#define ST7735R_FRMCTR1		0xb1
> +#define ST7735R_FRMCTR2		0xb2
> +#define ST7735R_FRMCTR3		0xb3
> +#define ST7735R_INVCTR		0xb4
> +#define ST7735R_PWCTR1		0xc0
> +#define ST7735R_PWCTR2		0xc1
> +#define ST7735R_PWCTR3		0xc2
> +#define ST7735R_PWCTR4		0xc3
> +#define ST7735R_PWCTR5		0xc4
> +#define ST7735R_VMCTR1		0xc5
> +#define ST7735R_GAMCTRP1	0xe0
> +#define ST7735R_GAMCTRN1	0xe1
> +
> +#define ST7735R_MY	BIT(7)
> +#define ST7735R_MX	BIT(6)
> +#define ST7735R_MV	BIT(5)
> +
> +static void st7735r_pipe_enable(struct drm_simple_display_pipe *pipe,
> +				struct drm_crtc_state *crtc_state)
> +{
> +	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
> +	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
> +	struct drm_framebuffer *fb = pipe->plane.fb;
> +	struct device *dev = tdev->drm->dev;
> +	int ret;
> +	u8 addr_mode;
> +
> +	DRM_DEBUG_KMS("\n");
> +
> +	mipi_dbi_hw_reset(mipi);
> +
> +	ret = mipi_dbi_command(mipi, MIPI_DCS_SOFT_RESET);
> +	if (ret) {
> +		DRM_DEV_ERROR(dev, "Error sending command %d\n", ret);
> +		return;
> +	}
> +
> +	msleep(150);
> +
> +	mipi_dbi_command(mipi, MIPI_DCS_EXIT_SLEEP_MODE);
> +	msleep(500);
> +
> +	mipi_dbi_command(mipi, ST7735R_FRMCTR1, 0x01, 0x2c, 0x2d);
> +	mipi_dbi_command(mipi, ST7735R_FRMCTR2, 0x01, 0x2c, 0x2d);
> +	mipi_dbi_command(mipi, ST7735R_FRMCTR3, 0x01, 0x2c, 0x2d, 0x01, 0x2c,
> +			 0x2d);
> +	mipi_dbi_command(mipi, ST7735R_INVCTR, 0x07);
> +	mipi_dbi_command(mipi, ST7735R_PWCTR1, 0xa2, 0x02, 0x84);
> +	mipi_dbi_command(mipi, ST7735R_PWCTR2, 0xc5);
> +	mipi_dbi_command(mipi, ST7735R_PWCTR3, 0x0a, 0x00);
> +	mipi_dbi_command(mipi, ST7735R_PWCTR4, 0x8a, 0x2a);
> +	mipi_dbi_command(mipi, ST7735R_PWCTR5, 0x8a, 0xee);
> +	mipi_dbi_command(mipi, ST7735R_VMCTR1, 0x0e);
> +	mipi_dbi_command(mipi, MIPI_DCS_EXIT_INVERT_MODE);
> +	switch (mipi->rotation) {
> +	default:
> +		addr_mode = ST7735R_MX | ST7735R_MY;
> +		break;
> +	case 90:
> +		addr_mode = ST7735R_MX | ST7735R_MV;
> +		break;
> +	case 180:
> +		addr_mode = 0;
> +		break;
> +	case 270:
> +		addr_mode = ST7735R_MY | ST7735R_MV;
> +		break;
> +	}
> +	mipi_dbi_command(mipi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
> +	mipi_dbi_command(mipi, MIPI_DCS_SET_PIXEL_FORMAT,
> +			 MIPI_DCS_PIXEL_FMT_16BIT);
> +	mipi_dbi_command(mipi, ST7735R_GAMCTRP1, 0x0f, 0x1a, 0x0f, 0x18, 0x2f,
> +			 0x28, 0x20, 0x22, 0x1f, 0x1b, 0x23, 0x37, 0x00, 0x07,
> +			 0x02, 0x10);
> +	mipi_dbi_command(mipi, ST7735R_GAMCTRN1, 0x0f, 0x1b, 0x0f, 0x17, 0x33,
> +			 0x2c, 0x29, 0x2e, 0x30, 0x30, 0x39, 0x3f, 0x00, 0x07,
> +			 0x03, 0x10);
> +	mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_ON);
> +
> +	msleep(100);
> +
> +	mipi_dbi_command(mipi, MIPI_DCS_ENTER_NORMAL_MODE);
> +
> +	msleep(10);

Please use 20ms here to avoid warning:

-:168: WARNING: msleep < 20ms can sleep for up to 20ms; see 
Documentation/timers/timers-howto.txt
#168: FILE: drivers/gpu/drm/tinydrm/st7735r.c:107:
+       msleep(10);

> +
> +	mipi->enabled = true;
> +
> +	if (fb)
> +		fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
> +
> +	tinydrm_enable_backlight(mipi->backlight);

The previous lines can be replaced with:

     mipi_dbi_pipe_enable(pipe, crtc_state);

I want us to use helpers as much as possible, and in this case the
flushing will be reworked in the future so less places to touch when
that happens.

> +}
> +
> +static void st7735r_pipe_disable(struct drm_simple_display_pipe *pipe)
> +{
> +	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
> +	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
> +

Please use mipi_dbi_pipe_disable() here.

> +	DRM_DEBUG_KMS("\n");
> +
> +	if (!mipi->enabled)
> +		return;
> +
> +	tinydrm_disable_backlight(mipi->backlight);
> +
> +	mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_OFF);

You turn off the panel, have you checked what it looks like if you don't
turn off backlight (which is optional in this driver)?

On the displays I have tried this on, all pixels turn white when they're
not driven, letting backlight through, giving an all white display.
That's why I have that blanking code in mipi_dbi_pipe_disable() when we
don't have backlight control and the reason I don't turn off the panel.
The power savings of not driving the panel is negligible AFAICR.

If you don't need DISPLAY_OFF, you can just use mipi_dbi_pipe_disable()
directly as the callback.

Noralf.

> +
> +	mipi->enabled = false;
> +}
> +
> +static const struct drm_simple_display_pipe_funcs st7735r_pipe_funcs = {
> +	.enable		= st7735r_pipe_enable,
> +	.disable	= st7735r_pipe_disable,
> +	.update		= tinydrm_display_pipe_update,
> +	.prepare_fb	= tinydrm_display_pipe_prepare_fb,
> +};
> +
> +static const struct drm_display_mode st7735r_mode = {
> +	TINYDRM_MODE(128, 160, 28, 35),
> +};
> +
> +DEFINE_DRM_GEM_CMA_FOPS(st7735r_fops);
> +
> +static struct drm_driver st7735r_driver = {
> +	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_PRIME |
> +				  DRIVER_ATOMIC,
> +	.fops			= &st7735r_fops,
> +	TINYDRM_GEM_DRIVER_OPS,
> +	.lastclose		= tinydrm_lastclose,
> +	.name			= "st7735r",
> +	.desc			= "Sitronix ST7735R",
> +	.date			= "20171128",
> +	.major			= 1,
> +	.minor			= 0,
> +};
> +
> +static const struct of_device_id st7735r_of_match[] = {
> +	{ .compatible = "sitronix,st7735r-jd-t18003-t01" },
> +	{},
> +};
> +MODULE_DEVICE_TABLE(of, st7735r_of_match);
> +
> +static const struct spi_device_id st7735r_id[] = {
> +	{ "st7735r-jd-t18003-t01", 0 },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(spi, st7735r_id);
> +
> +static int st7735r_probe(struct spi_device *spi)
> +{
> +	struct device *dev = &spi->dev;
> +	struct mipi_dbi *mipi;
> +	struct gpio_desc *dc;
> +	u32 rotation = 0;
> +	int ret;
> +
> +	mipi = devm_kzalloc(dev, sizeof(*mipi), GFP_KERNEL);
> +	if (!mipi)
> +		return -ENOMEM;
> +
> +	mipi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
> +	if (IS_ERR(mipi->reset)) {
> +		DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
> +		return PTR_ERR(mipi->reset);
> +	}
> +
> +	dc = devm_gpiod_get(dev, "dc", GPIOD_OUT_LOW);
> +	if (IS_ERR(dc)) {
> +		DRM_DEV_ERROR(dev, "Failed to get gpio 'dc'\n");
> +		return PTR_ERR(dc);
> +	}
> +
> +	mipi->backlight = tinydrm_of_find_backlight(dev);
> +	if (IS_ERR(mipi->backlight))
> +		return PTR_ERR(mipi->backlight);
> +
> +	device_property_read_u32(dev, "rotation", &rotation);
> +
> +	ret = mipi_dbi_spi_init(spi, mipi, dc);
> +	if (ret)
> +		return ret;
> +
> +	ret = mipi_dbi_init(&spi->dev, mipi, &st7735r_pipe_funcs,
> +			    &st7735r_driver, &st7735r_mode, rotation);
> +	if (ret)
> +		return ret;
> +
> +	spi_set_drvdata(spi, mipi);
> +
> +	return devm_tinydrm_register(&mipi->tinydrm);
> +}
> +
> +static void st7735r_shutdown(struct spi_device *spi)
> +{
> +	struct mipi_dbi *mipi = spi_get_drvdata(spi);
> +
> +	tinydrm_shutdown(&mipi->tinydrm);
> +}
> +
> +static struct spi_driver st7735r_spi_driver = {
> +	.driver = {
> +		.name = "st7735r",
> +		.owner = THIS_MODULE,
> +		.of_match_table = st7735r_of_match,
> +	},
> +	.id_table = st7735r_id,
> +	.probe = st7735r_probe,
> +	.shutdown = st7735r_shutdown,
> +};
> +module_spi_driver(st7735r_spi_driver);
> +
> +MODULE_DESCRIPTION("Sitronix ST7735R DRM driver");
> +MODULE_AUTHOR("David Lechner <david@lechnology.com>");
> +MODULE_LICENSE("GPL");
Noralf Trønnes Dec. 8, 2017, 2:11 p.m. UTC | #2 
Den 06.12.2017 19.27, skrev Noralf Trønnes:
>
> Den 29.11.2017 04.01, skrev David Lechner:
>> This adds a new driver for Sitronix ST7735R display panels.
>>
>> This has been tested using an Adafruit 1.8" TFT.
>>
>> Signed-off-by: David Lechner <david@lechnology.com>
>> ---

<snip>

>> diff --git a/drivers/gpu/drm/tinydrm/st7735r.c 
>> b/drivers/gpu/drm/tinydrm/st7735r.c

<snip>

>> +static struct drm_driver st7735r_driver = {
>> +    .driver_features    = DRIVER_GEM | DRIVER_MODESET | DRIVER_PRIME |
>> +                  DRIVER_ATOMIC,
>> +    .fops            = &st7735r_fops,
>> +    TINYDRM_GEM_DRIVER_OPS,
>> +    .lastclose        = tinydrm_lastclose,

tinydrm_lastclose() is going away, please use:

     .lastclose        = drm_fb_helper_lastclose,

Noralf.

>> +    .name            = "st7735r",
>> +    .desc            = "Sitronix ST7735R",
>> +    .date            = "20171128",
>> +    .major            = 1,
>> +    .minor            = 0,
>> +};
>> +
>> +static const struct of_device_id st7735r_of_match[] = {
>> +    { .compatible = "sitronix,st7735r-jd-t18003-t01" },
>> +    {},
>> +};
>> +MODULE_DEVICE_TABLE(of, st7735r_of_match);
>> +
>> +static const struct spi_device_id st7735r_id[] = {
>> +    { "st7735r-jd-t18003-t01", 0 },
>> +    { },
>> +};
>> +MODULE_DEVICE_TABLE(spi, st7735r_id);
>> +
>> +static int st7735r_probe(struct spi_device *spi)
>> +{
>> +    struct device *dev = &spi->dev;
>> +    struct mipi_dbi *mipi;
>> +    struct gpio_desc *dc;
>> +    u32 rotation = 0;
>> +    int ret;
>> +
>> +    mipi = devm_kzalloc(dev, sizeof(*mipi), GFP_KERNEL);
>> +    if (!mipi)
>> +        return -ENOMEM;
>> +
>> +    mipi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
>> +    if (IS_ERR(mipi->reset)) {
>> +        DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
>> +        return PTR_ERR(mipi->reset);
>> +    }
>> +
>> +    dc = devm_gpiod_get(dev, "dc", GPIOD_OUT_LOW);
>> +    if (IS_ERR(dc)) {
>> +        DRM_DEV_ERROR(dev, "Failed to get gpio 'dc'\n");
>> +        return PTR_ERR(dc);
>> +    }
>> +
>> +    mipi->backlight = tinydrm_of_find_backlight(dev);
>> +    if (IS_ERR(mipi->backlight))
>> +        return PTR_ERR(mipi->backlight);
>> +
>> +    device_property_read_u32(dev, "rotation", &rotation);
>> +
>> +    ret = mipi_dbi_spi_init(spi, mipi, dc);
>> +    if (ret)
>> +        return ret;
>> +
>> +    ret = mipi_dbi_init(&spi->dev, mipi, &st7735r_pipe_funcs,
>> +                &st7735r_driver, &st7735r_mode, rotation);
>> +    if (ret)
>> +        return ret;
>> +
>> +    spi_set_drvdata(spi, mipi);
>> +
>> +    return devm_tinydrm_register(&mipi->tinydrm);
>> +}
>> +
>> +static void st7735r_shutdown(struct spi_device *spi)
>> +{
>> +    struct mipi_dbi *mipi = spi_get_drvdata(spi);
>> +
>> +    tinydrm_shutdown(&mipi->tinydrm);
>> +}
>> +
>> +static struct spi_driver st7735r_spi_driver = {
>> +    .driver = {
>> +        .name = "st7735r",
>> +        .owner = THIS_MODULE,
>> +        .of_match_table = st7735r_of_match,
>> +    },
>> +    .id_table = st7735r_id,
>> +    .probe = st7735r_probe,
>> +    .shutdown = st7735r_shutdown,
>> +};
>> +module_spi_driver(st7735r_spi_driver);
>> +
>> +MODULE_DESCRIPTION("Sitronix ST7735R DRM driver");
>> +MODULE_AUTHOR("David Lechner <david@lechnology.com>");
>> +MODULE_LICENSE("GPL");
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
>
David Lechner Dec. 8, 2017, 9:25 p.m. UTC | #3 
On 12/06/2017 12:27 PM, Noralf Trønnes wrote:
> 
> Den 29.11.2017 04.01, skrev David Lechner:
>> This adds a new driver for Sitronix ST7735R display panels.
>>
>> This has been tested using an Adafruit 1.8" TFT.
>>
>> Signed-off-by: David Lechner <david@lechnology.com>
>> ---
>>   MAINTAINERS                       |   6 +
>>   drivers/gpu/drm/tinydrm/Kconfig   |  10 ++
>>   drivers/gpu/drm/tinydrm/Makefile  |   1 +
>>   drivers/gpu/drm/tinydrm/st7735r.c | 237 
>> ++++++++++++++++++++++++++++++++++++++
>>   4 files changed, 254 insertions(+)
>>   create mode 100644 drivers/gpu/drm/tinydrm/st7735r.c
>>
>> diff --git a/MAINTAINERS b/MAINTAINERS
>> index a174632..9c7707e 100644
>> --- a/MAINTAINERS
>> +++ b/MAINTAINERS
>> @@ -4462,6 +4462,12 @@ S:    Maintained
>>   F:    drivers/gpu/drm/tinydrm/st7586.c
>>   F:    Documentation/devicetree/bindings/display/st7586.txt
>> +DRM DRIVER FOR SITRONIX ST7735R PANELS
>> +M:    David Lechner <david@lechnology.com>
> 
> I know we haven't done this in the other tinydrm drivers, but I think
> we should start adding which tree the development is happening in:
> 
> T:    git git://anongit.freedesktop.org/drm/drm-misc

This is inherited, just like L:, so get_maintainers.pl --scm returns git 
git://anongit.freedesktop.org/drm/drm-misc already. So there doesn't 
seem to be a need to add this line.

> 
>> +S:    Maintained
>> +F:    drivers/gpu/drm/tinydrm/st7735r.c
>> +F:    Documentation/devicetree/bindings/display/st7735r.txt

<snip>

>> +}
>> +
>> +static void st7735r_pipe_disable(struct drm_simple_display_pipe *pipe)
>> +{
>> +    struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
>> +    struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
>> +
> 
> Please use mipi_dbi_pipe_disable() here.
> 
>> +    DRM_DEBUG_KMS("\n");
>> +
>> +    if (!mipi->enabled)
>> +        return;
>> +
>> +    tinydrm_disable_backlight(mipi->backlight);
>> +
>> +    mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_OFF);
> 
> You turn off the panel, have you checked what it looks like if you don't
> turn off backlight (which is optional in this driver)?
> 
> On the displays I have tried this on, all pixels turn white when they're
> not driven, letting backlight through, giving an all white display.
> That's why I have that blanking code in mipi_dbi_pipe_disable() when we
> don't have backlight control and the reason I don't turn off the panel.
> The power savings of not driving the panel is negligible AFAICR.
> 
> If you don't need DISPLAY_OFF, you can just use mipi_dbi_pipe_disable()
> directly as the callback.
> 

I tested this and you are right, it causes the panel to go white when a 
backlight is not specified, so I will just use mipi_dbi_pipe_disable().
Noralf Trønnes Dec. 9, 2017, 12:21 p.m. UTC | #4 
Den 29.11.2017 04.01, skrev David Lechner:
> This adds a new driver for Sitronix ST7735R display panels.
>
> This has been tested using an Adafruit 1.8" TFT.
>
> Signed-off-by: David Lechner <david@lechnology.com>
> ---
<snip>
> diff --git a/drivers/gpu/drm/tinydrm/st7735r.c b/drivers/gpu/drm/tinydrm/st7735r.c
<snip>
> +static struct drm_driver st7735r_driver = {
> +	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_PRIME |
> +				  DRIVER_ATOMIC,
> +	.fops			= &st7735r_fops,
> +	TINYDRM_GEM_DRIVER_OPS,
> +	.lastclose		= tinydrm_lastclose,

I was reminded of this since it would have made it easy to turn off the
panel and see if it turned white. Adding this makes it possible to send
commands from userspace for testing:

     .debugfs_init        = mipi_dbi_debugfs_init,

If you do that you have to set this to NULL since it's not possible to
read from the controller in this panel:

     mipi->read_commands = NULL;

Noralf.
diff mbox

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index a174632..9c7707e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4462,6 +4462,12 @@  S:	Maintained
 F:	drivers/gpu/drm/tinydrm/st7586.c
 F:	Documentation/devicetree/bindings/display/st7586.txt
 
+DRM DRIVER FOR SITRONIX ST7735R PANELS
+M:	David Lechner <david@lechnology.com>
+S:	Maintained
+F:	drivers/gpu/drm/tinydrm/st7735r.c
+F:	Documentation/devicetree/bindings/display/st7735r.txt
+
 DRM DRIVER FOR TDFX VIDEO CARDS
 S:	Orphan / Obsolete
 F:	drivers/gpu/drm/tdfx/
diff --git a/drivers/gpu/drm/tinydrm/Kconfig b/drivers/gpu/drm/tinydrm/Kconfig
index 90c5bd5..b0e567d 100644
--- a/drivers/gpu/drm/tinydrm/Kconfig
+++ b/drivers/gpu/drm/tinydrm/Kconfig
@@ -52,3 +52,13 @@  config TINYDRM_ST7586
 	  * LEGO MINDSTORMS EV3
 
 	  If M is selected the module will be called st7586.
+
+config TINYDRM_ST7735R
+	tristate "DRM support for Sitronix ST7735R display panels"
+	depends on DRM_TINYDRM && SPI
+	select TINYDRM_MIPI_DBI
+	help
+	  DRM driver Sitronix ST7735R with one of the following LCDs:
+	  * JD-T18003-T01 1.8" 128x160 TFT
+
+	  If M is selected the module will be called st7735r.
diff --git a/drivers/gpu/drm/tinydrm/Makefile b/drivers/gpu/drm/tinydrm/Makefile
index 8aeee53..49a1119 100644
--- a/drivers/gpu/drm/tinydrm/Makefile
+++ b/drivers/gpu/drm/tinydrm/Makefile
@@ -8,3 +8,4 @@  obj-$(CONFIG_TINYDRM_ILI9225)		+= ili9225.o
 obj-$(CONFIG_TINYDRM_MI0283QT)		+= mi0283qt.o
 obj-$(CONFIG_TINYDRM_REPAPER)		+= repaper.o
 obj-$(CONFIG_TINYDRM_ST7586)		+= st7586.o
+obj-$(CONFIG_TINYDRM_ST7735R)		+= st7735r.o
diff --git a/drivers/gpu/drm/tinydrm/st7735r.c b/drivers/gpu/drm/tinydrm/st7735r.c
new file mode 100644
index 0000000..6435b00
--- /dev/null
+++ b/drivers/gpu/drm/tinydrm/st7735r.c
@@ -0,0 +1,237 @@ 
+/*
+ * DRM driver for Sitronix ST7735R panels
+ *
+ * Copyright 2017 David Lechner <david@lechnology.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/delay.h>
+#include <linux/dma-buf.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/spi/spi.h>
+#include <video/mipi_display.h>
+
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/tinydrm/mipi-dbi.h>
+#include <drm/tinydrm/tinydrm-helpers.h>
+
+#define ST7735R_FRMCTR1		0xb1
+#define ST7735R_FRMCTR2		0xb2
+#define ST7735R_FRMCTR3		0xb3
+#define ST7735R_INVCTR		0xb4
+#define ST7735R_PWCTR1		0xc0
+#define ST7735R_PWCTR2		0xc1
+#define ST7735R_PWCTR3		0xc2
+#define ST7735R_PWCTR4		0xc3
+#define ST7735R_PWCTR5		0xc4
+#define ST7735R_VMCTR1		0xc5
+#define ST7735R_GAMCTRP1	0xe0
+#define ST7735R_GAMCTRN1	0xe1
+
+#define ST7735R_MY	BIT(7)
+#define ST7735R_MX	BIT(6)
+#define ST7735R_MV	BIT(5)
+
+static void st7735r_pipe_enable(struct drm_simple_display_pipe *pipe,
+				struct drm_crtc_state *crtc_state)
+{
+	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
+	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
+	struct drm_framebuffer *fb = pipe->plane.fb;
+	struct device *dev = tdev->drm->dev;
+	int ret;
+	u8 addr_mode;
+
+	DRM_DEBUG_KMS("\n");
+
+	mipi_dbi_hw_reset(mipi);
+
+	ret = mipi_dbi_command(mipi, MIPI_DCS_SOFT_RESET);
+	if (ret) {
+		DRM_DEV_ERROR(dev, "Error sending command %d\n", ret);
+		return;
+	}
+
+	msleep(150);
+
+	mipi_dbi_command(mipi, MIPI_DCS_EXIT_SLEEP_MODE);
+	msleep(500);
+
+	mipi_dbi_command(mipi, ST7735R_FRMCTR1, 0x01, 0x2c, 0x2d);
+	mipi_dbi_command(mipi, ST7735R_FRMCTR2, 0x01, 0x2c, 0x2d);
+	mipi_dbi_command(mipi, ST7735R_FRMCTR3, 0x01, 0x2c, 0x2d, 0x01, 0x2c,
+			 0x2d);
+	mipi_dbi_command(mipi, ST7735R_INVCTR, 0x07);
+	mipi_dbi_command(mipi, ST7735R_PWCTR1, 0xa2, 0x02, 0x84);
+	mipi_dbi_command(mipi, ST7735R_PWCTR2, 0xc5);
+	mipi_dbi_command(mipi, ST7735R_PWCTR3, 0x0a, 0x00);
+	mipi_dbi_command(mipi, ST7735R_PWCTR4, 0x8a, 0x2a);
+	mipi_dbi_command(mipi, ST7735R_PWCTR5, 0x8a, 0xee);
+	mipi_dbi_command(mipi, ST7735R_VMCTR1, 0x0e);
+	mipi_dbi_command(mipi, MIPI_DCS_EXIT_INVERT_MODE);
+	switch (mipi->rotation) {
+	default:
+		addr_mode = ST7735R_MX | ST7735R_MY;
+		break;
+	case 90:
+		addr_mode = ST7735R_MX | ST7735R_MV;
+		break;
+	case 180:
+		addr_mode = 0;
+		break;
+	case 270:
+		addr_mode = ST7735R_MY | ST7735R_MV;
+		break;
+	}
+	mipi_dbi_command(mipi, MIPI_DCS_SET_ADDRESS_MODE, addr_mode);
+	mipi_dbi_command(mipi, MIPI_DCS_SET_PIXEL_FORMAT,
+			 MIPI_DCS_PIXEL_FMT_16BIT);
+	mipi_dbi_command(mipi, ST7735R_GAMCTRP1, 0x0f, 0x1a, 0x0f, 0x18, 0x2f,
+			 0x28, 0x20, 0x22, 0x1f, 0x1b, 0x23, 0x37, 0x00, 0x07,
+			 0x02, 0x10);
+	mipi_dbi_command(mipi, ST7735R_GAMCTRN1, 0x0f, 0x1b, 0x0f, 0x17, 0x33,
+			 0x2c, 0x29, 0x2e, 0x30, 0x30, 0x39, 0x3f, 0x00, 0x07,
+			 0x03, 0x10);
+	mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_ON);
+
+	msleep(100);
+
+	mipi_dbi_command(mipi, MIPI_DCS_ENTER_NORMAL_MODE);
+
+	msleep(10);
+
+	mipi->enabled = true;
+
+	if (fb)
+		fb->funcs->dirty(fb, NULL, 0, 0, NULL, 0);
+
+	tinydrm_enable_backlight(mipi->backlight);
+}
+
+static void st7735r_pipe_disable(struct drm_simple_display_pipe *pipe)
+{
+	struct tinydrm_device *tdev = pipe_to_tinydrm(pipe);
+	struct mipi_dbi *mipi = mipi_dbi_from_tinydrm(tdev);
+
+	DRM_DEBUG_KMS("\n");
+
+	if (!mipi->enabled)
+		return;
+
+	tinydrm_disable_backlight(mipi->backlight);
+
+	mipi_dbi_command(mipi, MIPI_DCS_SET_DISPLAY_OFF);
+
+	mipi->enabled = false;
+}
+
+static const struct drm_simple_display_pipe_funcs st7735r_pipe_funcs = {
+	.enable		= st7735r_pipe_enable,
+	.disable	= st7735r_pipe_disable,
+	.update		= tinydrm_display_pipe_update,
+	.prepare_fb	= tinydrm_display_pipe_prepare_fb,
+};
+
+static const struct drm_display_mode st7735r_mode = {
+	TINYDRM_MODE(128, 160, 28, 35),
+};
+
+DEFINE_DRM_GEM_CMA_FOPS(st7735r_fops);
+
+static struct drm_driver st7735r_driver = {
+	.driver_features	= DRIVER_GEM | DRIVER_MODESET | DRIVER_PRIME |
+				  DRIVER_ATOMIC,
+	.fops			= &st7735r_fops,
+	TINYDRM_GEM_DRIVER_OPS,
+	.lastclose		= tinydrm_lastclose,
+	.name			= "st7735r",
+	.desc			= "Sitronix ST7735R",
+	.date			= "20171128",
+	.major			= 1,
+	.minor			= 0,
+};
+
+static const struct of_device_id st7735r_of_match[] = {
+	{ .compatible = "sitronix,st7735r-jd-t18003-t01" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, st7735r_of_match);
+
+static const struct spi_device_id st7735r_id[] = {
+	{ "st7735r-jd-t18003-t01", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(spi, st7735r_id);
+
+static int st7735r_probe(struct spi_device *spi)
+{
+	struct device *dev = &spi->dev;
+	struct mipi_dbi *mipi;
+	struct gpio_desc *dc;
+	u32 rotation = 0;
+	int ret;
+
+	mipi = devm_kzalloc(dev, sizeof(*mipi), GFP_KERNEL);
+	if (!mipi)
+		return -ENOMEM;
+
+	mipi->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(mipi->reset)) {
+		DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");
+		return PTR_ERR(mipi->reset);
+	}
+
+	dc = devm_gpiod_get(dev, "dc", GPIOD_OUT_LOW);
+	if (IS_ERR(dc)) {
+		DRM_DEV_ERROR(dev, "Failed to get gpio 'dc'\n");
+		return PTR_ERR(dc);
+	}
+
+	mipi->backlight = tinydrm_of_find_backlight(dev);
+	if (IS_ERR(mipi->backlight))
+		return PTR_ERR(mipi->backlight);
+
+	device_property_read_u32(dev, "rotation", &rotation);
+
+	ret = mipi_dbi_spi_init(spi, mipi, dc);
+	if (ret)
+		return ret;
+
+	ret = mipi_dbi_init(&spi->dev, mipi, &st7735r_pipe_funcs,
+			    &st7735r_driver, &st7735r_mode, rotation);
+	if (ret)
+		return ret;
+
+	spi_set_drvdata(spi, mipi);
+
+	return devm_tinydrm_register(&mipi->tinydrm);
+}
+
+static void st7735r_shutdown(struct spi_device *spi)
+{
+	struct mipi_dbi *mipi = spi_get_drvdata(spi);
+
+	tinydrm_shutdown(&mipi->tinydrm);
+}
+
+static struct spi_driver st7735r_spi_driver = {
+	.driver = {
+		.name = "st7735r",
+		.owner = THIS_MODULE,
+		.of_match_table = st7735r_of_match,
+	},
+	.id_table = st7735r_id,
+	.probe = st7735r_probe,
+	.shutdown = st7735r_shutdown,
+};
+module_spi_driver(st7735r_spi_driver);
+
+MODULE_DESCRIPTION("Sitronix ST7735R DRM driver");
+MODULE_AUTHOR("David Lechner <david@lechnology.com>");
+MODULE_LICENSE("GPL");