Re: [PATCH v6 3/3] drm/panel: Add support for the Raspberry Pi 7" Touchscreen.

On 09/28/2017 01:06 AM, Eric Anholt wrote:

This driver communicates with the Atmel microcontroller for sequencing the poweron of the TC358762 DSI-DPI bridge and controlling the backlight PWM.

v2: Set the same default orientation as the closed source firmware used, which is the best for viewing angle. v3: Rewrite as an i2c client driver after bridge driver rejection. v4: Finish probe without the DSI host, using the new delayed registration, and attach to the host during mipi_dsi_driver probe. v5: Rework to drop the "probe without DSI host" mode again, now that vc4 will create the host early on.

Reviewed-by: Archit Taneja architt@codeaurora.org

Signed-off-by: Eric Anholt eric@anholt.net

drivers/gpu/drm/panel/Kconfig | 8 + drivers/gpu/drm/panel/Makefile | 1 + .../gpu/drm/panel/panel-raspberrypi-touchscreen.c | 517 +++++++++++++++++++++ 3 files changed, 526 insertions(+) create mode 100644 drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig index 718d8ce15b1f..726f3fb3312d 100644 --- a/drivers/gpu/drm/panel/Kconfig +++ b/drivers/gpu/drm/panel/Kconfig @@ -82,6 +82,14 @@ config DRM_PANEL_PANASONIC_VVX10F034N00 WUXGA (1920x1200) Novatek NT1397-based DSI panel as found in some Xperia Z2 tablets

+config DRM_PANEL_RASPBERRYPI_TOUCHSCREEN

• tristate "Raspberry Pi 7-inch touchscreen panel"
• depends on DRM_MIPI_DSI
• help

•  Say Y here if you want to enable support for the Raspberry
  

•  Pi 7" Touchscreen.  To compile this driver as a module,
  

•  choose M here.
  

• config DRM_PANEL_SAMSUNG_S6E3HA2 tristate "Samsung S6E3HA2 DSI video mode panel" depends on OF

diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile index c8483fdd5b9b..77ede3467324 100644 --- a/drivers/gpu/drm/panel/Makefile +++ b/drivers/gpu/drm/panel/Makefile @@ -5,6 +5,7 @@ obj-$(CONFIG_DRM_PANEL_JDI_LT070ME05000) += panel-jdi-lt070me05000.o obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o obj-$(CONFIG_DRM_PANEL_ORISETECH_OTM8009A) += panel-orisetech-otm8009a.o obj-$(CONFIG_DRM_PANEL_PANASONIC_VVX10F034N00) += panel-panasonic-vvx10f034n00.o +obj-$(CONFIG_DRM_PANEL_RASPBERRYPI_TOUCHSCREEN) += panel-raspberrypi-touchscreen.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_LD9040) += panel-samsung-ld9040.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E3HA2) += panel-samsung-s6e3ha2.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E63J0X03) += panel-samsung-s6e63j0x03.o diff --git a/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c new file mode 100644 index 000000000000..4237a0cbcdcc --- /dev/null +++ b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c @@ -0,0 +1,517 @@ +/*

• • Copyright © 2016-2017 Broadcom
• • This program is free software; you can redistribute it and/or modify
• • it under the terms of the GNU General Public License version 2 as
• • published by the Free Software Foundation.
• • Portions of this file (derived from panel-simple.c) are:
• • Copyright (C) 2013, NVIDIA Corporation. All rights reserved.
• • 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, sub license,
• • 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 NON-INFRINGEMENT. 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.
• */

+/**

• • Raspberry Pi 7" touchscreen panel driver.
• • The 7" touchscreen consists of a DPI LCD panel, a Toshiba
• • TC358762XBG DSI-DPI bridge, and an I2C-connected Atmel ATTINY88-MUR
• • controlling power management, the LCD PWM, and initial register
• • setup of the Tohsiba.
• • This driver controls the TC358762 and ATTINY88, presenting a DSI
• • device with a drm_panel.
• */

+#include <linux/delay.h> +#include <linux/err.h> +#include <linux/fb.h> +#include <linux/gpio.h> +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_graph.h> +#include <linux/pm.h>

+#include <drm/drm_panel.h> +#include <drm/drmP.h> +#include <drm/drm_crtc.h> +#include <drm/drm_mipi_dsi.h> +#include <drm/drm_panel.h>

+#define RPI_DSI_DRIVER_NAME "rpi-ts-dsi"

+/* I2C registers of the Atmel microcontroller. */ +enum REG_ADDR {

• REG_ID = 0x80,
• REG_PORTA, /* BIT(2) for horizontal flip, BIT(3) for vertical flip */
• REG_PORTB,
• REG_PORTC,
• REG_PORTD,
• REG_POWERON,
• REG_PWM,
• REG_DDRA,
• REG_DDRB,
• REG_DDRC,
• REG_DDRD,
• REG_TEST,
• REG_WR_ADDRL,
• REG_WR_ADDRH,
• REG_READH,
• REG_READL,
• REG_WRITEH,
• REG_WRITEL,
• REG_ID2,

+};

+/* We only turn the PWM on or off, without varying values. */ +#define RPI_TOUCHSCREEN_MAX_BRIGHTNESS 1

+/* DSI D-PHY Layer Registers */ +#define D0W_DPHYCONTTX 0x0004 +#define CLW_DPHYCONTRX 0x0020 +#define D0W_DPHYCONTRX 0x0024 +#define D1W_DPHYCONTRX 0x0028 +#define COM_DPHYCONTRX 0x0038 +#define CLW_CNTRL 0x0040 +#define D0W_CNTRL 0x0044 +#define D1W_CNTRL 0x0048 +#define DFTMODE_CNTRL 0x0054

+/* DSI PPI Layer Registers */ +#define PPI_STARTPPI 0x0104 +#define PPI_BUSYPPI 0x0108 +#define PPI_LINEINITCNT 0x0110 +#define PPI_LPTXTIMECNT 0x0114 +#define PPI_CLS_ATMR 0x0140 +#define PPI_D0S_ATMR 0x0144 +#define PPI_D1S_ATMR 0x0148 +#define PPI_D0S_CLRSIPOCOUNT 0x0164 +#define PPI_D1S_CLRSIPOCOUNT 0x0168 +#define CLS_PRE 0x0180 +#define D0S_PRE 0x0184 +#define D1S_PRE 0x0188 +#define CLS_PREP 0x01A0 +#define D0S_PREP 0x01A4 +#define D1S_PREP 0x01A8 +#define CLS_ZERO 0x01C0 +#define D0S_ZERO 0x01C4 +#define D1S_ZERO 0x01C8 +#define PPI_CLRFLG 0x01E0 +#define PPI_CLRSIPO 0x01E4 +#define HSTIMEOUT 0x01F0 +#define HSTIMEOUTENABLE 0x01F4

+/* DSI Protocol Layer Registers */ +#define DSI_STARTDSI 0x0204 +#define DSI_BUSYDSI 0x0208 +#define DSI_LANEENABLE 0x0210 +# define DSI_LANEENABLE_CLOCK BIT(0) +# define DSI_LANEENABLE_D0 BIT(1) +# define DSI_LANEENABLE_D1 BIT(2)

+#define DSI_LANESTATUS0 0x0214 +#define DSI_LANESTATUS1 0x0218 +#define DSI_INTSTATUS 0x0220 +#define DSI_INTMASK 0x0224 +#define DSI_INTCLR 0x0228 +#define DSI_LPTXTO 0x0230 +#define DSI_MODE 0x0260 +#define DSI_PAYLOAD0 0x0268 +#define DSI_PAYLOAD1 0x026C +#define DSI_SHORTPKTDAT 0x0270 +#define DSI_SHORTPKTREQ 0x0274 +#define DSI_BTASTA 0x0278 +#define DSI_BTACLR 0x027C

+/* DSI General Registers */ +#define DSIERRCNT 0x0300 +#define DSISIGMOD 0x0304

+/* DSI Application Layer Registers */ +#define APLCTRL 0x0400 +#define APLSTAT 0x0404 +#define APLERR 0x0408 +#define PWRMOD 0x040C +#define RDPKTLN 0x0410 +#define PXLFMT 0x0414 +#define MEMWRCMD 0x0418

+/* LCDC/DPI Host Registers */ +#define LCDCTRL 0x0420 +#define HSR 0x0424 +#define HDISPR 0x0428 +#define VSR 0x042C +#define VDISPR 0x0430 +#define VFUEN 0x0434

+/* DBI-B Host Registers */ +#define DBIBCTRL 0x0440

+/* SPI Master Registers */ +#define SPICMR 0x0450 +#define SPITCR 0x0454

+/* System Controller Registers */ +#define SYSSTAT 0x0460 +#define SYSCTRL 0x0464 +#define SYSPLL1 0x0468 +#define SYSPLL2 0x046C +#define SYSPLL3 0x0470 +#define SYSPMCTRL 0x047C

+/* GPIO Registers */ +#define GPIOC 0x0480 +#define GPIOO 0x0484 +#define GPIOI 0x0488

+/* I2C Registers */ +#define I2CCLKCTRL 0x0490

+/* Chip/Rev Registers */ +#define IDREG 0x04A0

+/* Debug Registers */ +#define WCMDQUEUE 0x0500 +#define RCMDQUEUE 0x0504

+struct rpi_touchscreen {

• struct drm_panel base;
• struct mipi_dsi_device *dsi;
• struct i2c_client *i2c;

+};

+static const struct drm_display_mode rpi_touchscreen_modes[] = {

• {

• /* Modeline comes from the Raspberry Pi firmware, with HFP=1
  

•  * plugged in and clock re-computed from that.
  

•  */
  

• .clock = 25979400 / 1000,
  

• .hdisplay = 800,
  

• .hsync_start = 800 + 1,
  

• .hsync_end = 800 + 1 + 2,
  

• .htotal = 800 + 1 + 2 + 46,
  

• .vdisplay = 480,
  

• .vsync_start = 480 + 7,
  

• .vsync_end = 480 + 7 + 2,
  

• .vtotal = 480 + 7 + 2 + 21,
  

• .vrefresh = 60,
  

• },

+};

+static struct rpi_touchscreen *panel_to_ts(struct drm_panel *panel) +{

• return container_of(panel, struct rpi_touchscreen, base);

+}

+static u8 rpi_touchscreen_i2c_read(struct rpi_touchscreen *ts, u8 reg) +{

• return i2c_smbus_read_byte_data(ts->i2c, reg);

+}

+static void rpi_touchscreen_i2c_write(struct rpi_touchscreen *ts,

• 		      u8 reg, u8 val)
  

+{

• int ret;
• ret = i2c_smbus_write_byte_data(ts->i2c, reg, val);
• if (ret)

• dev_err(&ts->dsi->dev, "I2C write failed: %d\n", ret);
  

+}

+static int rpi_touchscreen_write(struct rpi_touchscreen *ts, u16 reg, u32 val) +{ +#if 0

• /* The firmware uses LP DSI transactions like this to bring up

• * the hardware, which should be faster than using I2C to then
  

• * pass to the Toshiba.  However, I was unable to get it to
  

• * work.
  

• */
  

• u8 msg[] = {

• reg,
  

• reg >> 8,
  

• val,
  

• val >> 8,
  

• val >> 16,
  

• val >> 24,
  

• };
• mipi_dsi_dcs_write_buffer(ts->dsi, msg, sizeof(msg));

+#else

• rpi_touchscreen_i2c_write(ts, REG_WR_ADDRH, reg >> 8);
• rpi_touchscreen_i2c_write(ts, REG_WR_ADDRL, reg);
• rpi_touchscreen_i2c_write(ts, REG_WRITEH, val >> 8);
• rpi_touchscreen_i2c_write(ts, REG_WRITEL, val);

+#endif

• return 0;

+}

+static int rpi_touchscreen_disable(struct drm_panel *panel) +{

• struct rpi_touchscreen *ts = panel_to_ts(panel);
• rpi_touchscreen_i2c_write(ts, REG_PWM, 0);
• rpi_touchscreen_i2c_write(ts, REG_POWERON, 0);
• udelay(1);
• return 0;

+}

+static int rpi_touchscreen_noop(struct drm_panel *panel) +{

• return 0;

+}

+static int rpi_touchscreen_enable(struct drm_panel *panel) +{

• struct rpi_touchscreen *ts = panel_to_ts(panel);
• int i;
• rpi_touchscreen_i2c_write(ts, REG_POWERON, 1);
• /* Wait for nPWRDWN to go low to indicate poweron is done. */
• for (i = 0; i < 100; i++) {

• if (rpi_touchscreen_i2c_read(ts, REG_PORTB) & 1)
  

• 	break;
  

• }
• rpi_touchscreen_write(ts, DSI_LANEENABLE,

• 	      DSI_LANEENABLE_CLOCK |
  

• 	      DSI_LANEENABLE_D0);
  

• rpi_touchscreen_write(ts, PPI_D0S_CLRSIPOCOUNT, 0x05);
• rpi_touchscreen_write(ts, PPI_D1S_CLRSIPOCOUNT, 0x05);
• rpi_touchscreen_write(ts, PPI_D0S_ATMR, 0x00);
• rpi_touchscreen_write(ts, PPI_D1S_ATMR, 0x00);
• rpi_touchscreen_write(ts, PPI_LPTXTIMECNT, 0x03);
• rpi_touchscreen_write(ts, SPICMR, 0x00);
• rpi_touchscreen_write(ts, LCDCTRL, 0x00100150);
• rpi_touchscreen_write(ts, SYSCTRL, 0x040f);
• msleep(100);
• rpi_touchscreen_write(ts, PPI_STARTPPI, 0x01);
• rpi_touchscreen_write(ts, DSI_STARTDSI, 0x01);
• msleep(100);
• /* Turn on the backlight. */
• rpi_touchscreen_i2c_write(ts, REG_PWM, 255);
• /* Default to the same orientation as the closed source

• * firmware used for the panel.  Runtime rotation
  

• * configuration will be supported using VC4's plane
  

• * orientation bits.
  

• */
  

• rpi_touchscreen_i2c_write(ts, REG_PORTA, BIT(2));
• return 0;

+}

+static int rpi_touchscreen_get_modes(struct drm_panel *panel) +{

• struct drm_connector *connector = panel->connector;
• struct drm_device *drm = panel->drm;
• unsigned int i, num = 0;
• static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
• for (i = 0; i < ARRAY_SIZE(rpi_touchscreen_modes); i++) {

• const struct drm_display_mode *m = &rpi_touchscreen_modes[i];
  

• struct drm_display_mode *mode;
  

• mode = drm_mode_duplicate(drm, m);
  

• if (!mode) {
  

• 	dev_err(drm->dev, "failed to add mode %ux%u@%u\n",
  

• 		m->hdisplay, m->vdisplay, m->vrefresh);
  

• 	continue;
  

• }
  

• mode->type |= DRM_MODE_TYPE_DRIVER;
  

• if (i == 0)
  

• 	mode->type |= DRM_MODE_TYPE_PREFERRED;
  

• drm_mode_set_name(mode);
  

• drm_mode_probed_add(connector, mode);
  

• num++;
  

• }
• connector->display_info.bpc = 8;
• connector->display_info.width_mm = 154;
• connector->display_info.height_mm = 86;
• drm_display_info_set_bus_formats(&connector->display_info,

• 			 &bus_format, 1);
  

• return num;

+}

+static const struct drm_panel_funcs rpi_touchscreen_funcs = {

• .disable = rpi_touchscreen_disable,
• .unprepare = rpi_touchscreen_noop,
• .prepare = rpi_touchscreen_noop,
• .enable = rpi_touchscreen_enable,
• .get_modes = rpi_touchscreen_get_modes,

+};

+static int rpi_touchscreen_probe(struct i2c_client *i2c,

• 		 const struct i2c_device_id *id)
  

+{

• struct device *dev = &i2c->dev;
• struct rpi_touchscreen *ts;
• struct device_node *endpoint, *dsi_host_node;
• struct mipi_dsi_host *host;
• int ret, ver;
• struct mipi_dsi_device_info info = {

• .type = RPI_DSI_DRIVER_NAME,
  

• .channel = 0,
  

• .node = NULL,
  

• };
• ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
• if (!ts)

• return -ENOMEM;
  

• i2c_set_clientdata(i2c, ts);
• ts->i2c = i2c;
• ver = rpi_touchscreen_i2c_read(ts, REG_ID);
• if (ver < 0) {

• dev_err(dev, "Atmel I2C read failed: %d\n", ver);
  

• return -ENODEV;
  

• }
• switch (ver) {
• case 0xde: /* ver 1 */
• case 0xc3: /* ver 2 */

• break;
  

• default:

• dev_err(dev, "Unknown Atmel firmware revision: 0x%02x\n", ver);
  

• return -ENODEV;
  

• }
• /* Turn off at boot, so we can cleanly sequence powering on. */
• rpi_touchscreen_i2c_write(ts, REG_POWERON, 0);
• /* Look up the DSI host. It needs to probe before we do. */
• endpoint = of_graph_get_next_endpoint(dev->of_node, NULL);
• dsi_host_node = of_graph_get_remote_port_parent(endpoint);
• host = of_find_mipi_dsi_host_by_node(dsi_host_node);
• of_node_put(dsi_host_node);
• if (!host) {

• of_node_put(endpoint);
  

• return -EPROBE_DEFER;
  

• }
• info.node = of_graph_get_remote_port(endpoint);
• of_node_put(endpoint);
• ts->dsi = mipi_dsi_device_register_full(host, &info);
• if (IS_ERR(ts->dsi)) {

• dev_err(dev, "DSI device registration failed: %ld\n",
  

• 	PTR_ERR(ts->dsi));
  

• return PTR_ERR(ts->dsi);
  

• }
• ts->base.dev = dev;
• ts->base.funcs = &rpi_touchscreen_funcs;
• /* This appears last, as it's what will unblock the DSI host

• * driver's component bind function.
  

• */
  

• ret = drm_panel_add(&ts->base);
• if (ret)

• return ret;
  

• return 0;

+}

+static int rpi_touchscreen_remove(struct i2c_client *i2c) +{

• struct rpi_touchscreen *ts = i2c_get_clientdata(i2c);
• mipi_dsi_detach(ts->dsi);
• drm_panel_remove(&ts->base);
• mipi_dsi_device_unregister(ts->dsi);
• kfree(ts->dsi);
• return 0;

+}

+static int rpi_touchscreen_dsi_probe(struct mipi_dsi_device *dsi) +{

• int ret;
• dsi->mode_flags = (MIPI_DSI_MODE_VIDEO |

• 	   MIPI_DSI_MODE_VIDEO_SYNC_PULSE |
  

• 	   MIPI_DSI_MODE_LPM);
  

• dsi->format = MIPI_DSI_FMT_RGB888;
• dsi->lanes = 1;
• ret = mipi_dsi_attach(dsi);
• if (ret)

• dev_err(&dsi->dev, "failed to attach dsi to host: %d\n", ret);
  

• return ret;

+}

+static struct mipi_dsi_driver rpi_touchscreen_dsi_driver = {

• .driver.name = RPI_DSI_DRIVER_NAME,
• .probe = rpi_touchscreen_dsi_probe,

+};

+static const struct of_device_id rpi_touchscreen_of_ids[] = {

• { .compatible = "raspberrypi,7inch-touchscreen-panel" },
• { } /* sentinel */

+}; +MODULE_DEVICE_TABLE(of, rpi_touchscreen_of_ids);

+static struct i2c_driver rpi_touchscreen_driver = {

• .driver = {

• .name = "rpi_touchscreen",
  

• .of_match_table = rpi_touchscreen_of_ids,
  

• },
• .probe = rpi_touchscreen_probe,
• .remove = rpi_touchscreen_remove,

+};

+static int __init rpi_touchscreen_init(void) +{

• mipi_dsi_driver_register(&rpi_touchscreen_dsi_driver);
• return i2c_add_driver(&rpi_touchscreen_driver);

+} +module_init(rpi_touchscreen_init);

+static void __exit rpi_touchscreen_exit(void) +{

• i2c_del_driver(&rpi_touchscreen_driver);
• mipi_dsi_driver_unregister(&rpi_touchscreen_dsi_driver);

+} +module_exit(rpi_touchscreen_exit);

+MODULE_AUTHOR("Eric Anholt eric@anholt.net"); +MODULE_DESCRIPTION("Raspberry Pi 7-inch touchscreen driver"); +MODULE_LICENSE("GPL v2");