diff options
Diffstat (limited to 'drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c')
| -rw-r--r-- | drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c | 514 |
1 files changed, 514 insertions, 0 deletions
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..890fd6ff397c --- /dev/null +++ b/drivers/gpu/drm/panel/panel-raspberrypi-touchscreen.c @@ -0,0 +1,514 @@ +/* + * 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, +}; + +/* 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"); |