--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * MIPI-DSI Sony ACX424AKP panel driver. This is a 480x864
+ * AMOLED panel with a command-only DSI interface.
+ *
+ * Copyright (C) Linaro Ltd. 2019
+ * Author: Linus Walleij
+ * Based on code and know-how from Marcus Lorentzon
+ * Copyright (C) ST-Ericsson SA 2010
+ */
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/regulator/consumer.h>
+
+#include <video/mipi_display.h>
+
+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_print.h>
+
+#define ACX424_DCS_READ_ID1 0xDA
+#define ACX424_DCS_READ_ID2 0xDB
+#define ACX424_DCS_READ_ID3 0xDC
+#define ACX424_DCS_SET_MDDI 0xAE
+
+/*
+ * Sony seems to use vendor ID 0x81
+ */
+#define DISPLAY_SONY_ACX424AKP_ID1 0x811b
+#define DISPLAY_SONY_ACX424AKP_ID2 0x811a
+/*
+ * The third ID looks like a bug, vendor IDs begin at 0x80
+ * and panel 00 ... seems like default values.
+ */
+#define DISPLAY_SONY_ACX424AKP_ID3 0x8000
+
+struct acx424akp {
+ struct drm_panel panel;
+ struct device *dev;
+ struct backlight_device *bl;
+ struct regulator *supply;
+ struct gpio_desc *reset_gpio;
+ bool video_mode;
+};
+
+static const struct drm_display_mode sony_acx424akp_vid_mode = {
+ .clock = 330000,
+ .hdisplay = 480,
+ .hsync_start = 480 + 15,
+ .hsync_end = 480 + 15 + 0,
+ .htotal = 480 + 15 + 0 + 15,
+ .vdisplay = 864,
+ .vsync_start = 864 + 14,
+ .vsync_end = 864 + 14 + 1,
+ .vtotal = 864 + 14 + 1 + 11,
+ .vrefresh = 60,
+ .width_mm = 48,
+ .height_mm = 84,
+ .flags = DRM_MODE_FLAG_PVSYNC,
+};
+
+/*
+ * The timings are not very helpful as the display is used in
+ * command mode using the maximum HS frequency.
+ */
+static const struct drm_display_mode sony_acx424akp_cmd_mode = {
+ .clock = 420160,
+ .hdisplay = 480,
+ .hsync_start = 480 + 154,
+ .hsync_end = 480 + 154 + 16,
+ .htotal = 480 + 154 + 16 + 32,
+ .vdisplay = 864,
+ .vsync_start = 864 + 1,
+ .vsync_end = 864 + 1 + 1,
+ .vtotal = 864 + 1 + 1 + 1,
+ /*
+ * Some desired refresh rate, experiments at the maximum "pixel"
+ * clock speed (HS clock 420 MHz) yields around 117Hz.
+ */
+ .vrefresh = 60,
+ .width_mm = 48,
+ .height_mm = 84,
+};
+
+static inline struct acx424akp *panel_to_acx424akp(struct drm_panel *panel)
+{
+ return container_of(panel, struct acx424akp, panel);
+}
+
+#define FOSC 20 /* 20Mhz */
+#define SCALE_FACTOR_NS_DIV_MHZ 1000
+
+static int acx424akp_set_brightness(struct backlight_device *bl)
+{
+ struct acx424akp *acx = bl_get_data(bl);
+ struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
+ int period_ns = 1023;
+ int duty_ns = bl->props.brightness;
+ u8 pwm_ratio;
+ u8 pwm_div;
+ u8 par;
+ int ret;
+
+ /* Calculate the PWM duty cycle in n/256's */
+ pwm_ratio = max(((duty_ns * 256) / period_ns) - 1, 1);
+ pwm_div = max(1,
+ ((FOSC * period_ns) / 256) /
+ SCALE_FACTOR_NS_DIV_MHZ);
+
+ /* Set up PWM dutycycle ONE byte (differs from the standard) */
+ DRM_DEV_DEBUG(acx->dev, "calculated duty cycle %02x\n", pwm_ratio);
+ ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_SET_DISPLAY_BRIGHTNESS,
+ &pwm_ratio, 1);
+ if (ret < 0) {
+ DRM_DEV_ERROR(acx->dev,
+ "failed to set display PWM ratio (%d)\n",
+ ret);
+ return ret;
+ }
+
+ /*
+ * Sequence to write PWMDIV:
+ * address data
+ * 0xF3 0xAA CMD2 Unlock
+ * 0x00 0x01 Enter CMD2 page 0
+ * 0X7D 0x01 No reload MTP of CMD2 P1
+ * 0x22 PWMDIV
+ * 0x7F 0xAA CMD2 page 1 lock
+ */
+ par = 0xaa;
+ ret = mipi_dsi_dcs_write(dsi, 0xf3, &par, 1);
+ if (ret < 0) {
+ DRM_DEV_ERROR(acx->dev,
+ "failed to unlock CMD 2 (%d)\n",
+ ret);
+ return ret;
+ }
+ par = 0x01;
+ ret = mipi_dsi_dcs_write(dsi, 0x00, &par, 1);
+ if (ret < 0) {
+ DRM_DEV_ERROR(acx->dev,
+ "failed to enter page 1 (%d)\n",
+ ret);
+ return ret;
+ }
+ par = 0x01;
+ ret = mipi_dsi_dcs_write(dsi, 0x7d, &par, 1);
+ if (ret < 0) {
+ DRM_DEV_ERROR(acx->dev,
+ "failed to disable MTP reload (%d)\n",
+ ret);
+ return ret;
+ }
+ ret = mipi_dsi_dcs_write(dsi, 0x22, &pwm_div, 1);
+ if (ret < 0) {
+ DRM_DEV_ERROR(acx->dev,
+ "failed to set PWM divisor (%d)\n",
+ ret);
+ return ret;
+ }
+ par = 0xaa;
+ ret = mipi_dsi_dcs_write(dsi, 0x7f, &par, 1);
+ if (ret < 0) {
+ DRM_DEV_ERROR(acx->dev,
+ "failed to lock CMD 2 (%d)\n",
+ ret);
+ return ret;
+ }
+
+ /* Enable backlight */
+ par = 0x24;
+ ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
+ &par, 1);
+ if (ret < 0) {
+ DRM_DEV_ERROR(acx->dev,
+ "failed to enable display backlight (%d)\n",
+ ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct backlight_ops acx424akp_bl_ops = {
+ .update_status = acx424akp_set_brightness,
+};
+
+static int acx424akp_read_id(struct acx424akp *acx)
+{
+ struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
+ u8 vendor, version, panel;
+ u16 val;
+ int ret;
+
+ ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID1, &vendor, 1);
+ if (ret < 0) {
+ DRM_DEV_ERROR(acx->dev, "could not vendor ID byte\n");
+ return ret;
+ }
+ ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID2, &version, 1);
+ if (ret < 0) {
+ DRM_DEV_ERROR(acx->dev, "could not read device version byte\n");
+ return ret;
+ }
+ ret = mipi_dsi_dcs_read(dsi, ACX424_DCS_READ_ID3, &panel, 1);
+ if (ret < 0) {
+ DRM_DEV_ERROR(acx->dev, "could not read panel ID byte\n");
+ return ret;
+ }
+
+ if (vendor == 0x00) {
+ DRM_DEV_ERROR(acx->dev, "device vendor ID is zero\n");
+ return -ENODEV;
+ }
+
+ val = (vendor << 8) | panel;
+ switch (val) {
+ case DISPLAY_SONY_ACX424AKP_ID1:
+ case DISPLAY_SONY_ACX424AKP_ID2:
+ case DISPLAY_SONY_ACX424AKP_ID3:
+ DRM_DEV_INFO(acx->dev,
+ "MTP vendor: %02x, version: %02x, panel: %02x\n",
+ vendor, version, panel);
+ break;
+ default:
+ DRM_DEV_INFO(acx->dev,
+ "unknown vendor: %02x, version: %02x, panel: %02x\n",
+ vendor, version, panel);
+ break;
+ }
+
+ return 0;
+}
+
+static int acx424akp_power_on(struct acx424akp *acx)
+{
+ int ret;
+
+ ret = regulator_enable(acx->supply);
+ if (ret) {
+ DRM_DEV_ERROR(acx->dev, "failed to enable supply (%d)\n", ret);
+ return ret;
+ }
+
+ /* Assert RESET */
+ gpiod_set_value_cansleep(acx->reset_gpio, 1);
+ udelay(20);
+ /* De-assert RESET */
+ gpiod_set_value_cansleep(acx->reset_gpio, 0);
+ usleep_range(11000, 20000);
+
+ return 0;
+}
+
+static void acx424akp_power_off(struct acx424akp *acx)
+{
+ /* Assert RESET */
+ gpiod_set_value_cansleep(acx->reset_gpio, 1);
+ usleep_range(11000, 20000);
+
+ regulator_disable(acx->supply);
+}
+
+static int acx424akp_prepare(struct drm_panel *panel)
+{
+ struct acx424akp *acx = panel_to_acx424akp(panel);
+ struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
+ const u8 mddi = 3;
+ int ret;
+
+ ret = acx424akp_power_on(acx);
+ if (ret)
+ return ret;
+
+ ret = acx424akp_read_id(acx);
+ if (ret) {
+ DRM_DEV_ERROR(acx->dev, "failed to read panel ID (%d)\n", ret);
+ goto err_power_off;
+ }
+
+ /* Enabe tearing mode: send TE (tearing effect) at VBLANK */
+ ret = mipi_dsi_dcs_set_tear_on(dsi,
+ MIPI_DSI_DCS_TEAR_MODE_VBLANK);
+ if (ret) {
+ DRM_DEV_ERROR(acx->dev, "failed to enable vblank TE (%d)\n",
+ ret);
+ goto err_power_off;
+ }
+
+ /*
+ * Set MDDI
+ *
+ * This presumably deactivates the Qualcomm MDDI interface and
+ * selects DSI, similar code is found in other drivers such as the
+ * Sharp LS043T1LE01 which makes us suspect that this panel may be
+ * using a Novatek NT35565 or similar display driver chip that shares
+ * this command. Due to the lack of documentation we cannot know for
+ * sure.
+ */
+ ret = mipi_dsi_dcs_write(dsi, ACX424_DCS_SET_MDDI,
+ &mddi, sizeof(mddi));
+ if (ret < 0) {
+ DRM_DEV_ERROR(acx->dev, "failed to set MDDI (%d)\n", ret);
+ goto err_power_off;
+ }
+
+ /* Exit sleep mode */
+ ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
+ if (ret) {
+ DRM_DEV_ERROR(acx->dev, "failed to exit sleep mode (%d)\n",
+ ret);
+ goto err_power_off;
+ }
+ msleep(140);
+
+ ret = mipi_dsi_dcs_set_display_on(dsi);
+ if (ret) {
+ DRM_DEV_ERROR(acx->dev, "failed to turn display on (%d)\n",
+ ret);
+ goto err_power_off;
+ }
+ if (acx->video_mode) {
+ /* In video mode turn peripheral on */
+ ret = mipi_dsi_turn_on_peripheral(dsi);
+ if (ret) {
+ dev_err(acx->dev, "failed to turn on peripheral\n");
+ goto err_power_off;
+ }
+ }
+
+ acx->bl->props.power = FB_BLANK_NORMAL;
+
+ return 0;
+
+err_power_off:
+ acx424akp_power_off(acx);
+ return ret;
+}
+
+static int acx424akp_unprepare(struct drm_panel *panel)
+{
+ struct acx424akp *acx = panel_to_acx424akp(panel);
+ struct mipi_dsi_device *dsi = to_mipi_dsi_device(acx->dev);
+ u8 par;
+ int ret;
+
+ /* Disable backlight */
+ par = 0x00;
+ ret = mipi_dsi_dcs_write(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY,
+ &par, 1);
+ if (ret) {
+ DRM_DEV_ERROR(acx->dev,
+ "failed to disable display backlight (%d)\n",
+ ret);
+ return ret;
+ }
+
+ ret = mipi_dsi_dcs_set_display_off(dsi);
+ if (ret) {
+ DRM_DEV_ERROR(acx->dev, "failed to turn display off (%d)\n",
+ ret);
+ return ret;
+ }
+
+ /* Enter sleep mode */
+ ret = mipi_dsi_dcs_enter_sleep_mode(dsi);
+ if (ret) {
+ DRM_DEV_ERROR(acx->dev, "failed to enter sleep mode (%d)\n",
+ ret);
+ return ret;
+ }
+ msleep(85);
+
+ acx424akp_power_off(acx);
+ acx->bl->props.power = FB_BLANK_POWERDOWN;
+
+ return 0;
+}
+
+static int acx424akp_enable(struct drm_panel *panel)
+{
+ struct acx424akp *acx = panel_to_acx424akp(panel);
+
+ /*
+ * The backlight is on as long as the display is on
+ * so no use to call backlight_enable() here.
+ */
+ acx->bl->props.power = FB_BLANK_UNBLANK;
+
+ return 0;
+}
+
+static int acx424akp_disable(struct drm_panel *panel)
+{
+ struct acx424akp *acx = panel_to_acx424akp(panel);
+
+ /*
+ * The backlight is on as long as the display is on
+ * so no use to call backlight_disable() here.
+ */
+ acx->bl->props.power = FB_BLANK_NORMAL;
+
+ return 0;
+}
+
+static int acx424akp_get_modes(struct drm_panel *panel,
+ struct drm_connector *connector)
+{
+ struct acx424akp *acx = panel_to_acx424akp(panel);
+ struct drm_display_mode *mode;
+
+ if (acx->video_mode)
+ mode = drm_mode_duplicate(connector->dev,
+ &sony_acx424akp_vid_mode);
+ else
+ mode = drm_mode_duplicate(connector->dev,
+ &sony_acx424akp_cmd_mode);
+ if (!mode) {
+ DRM_ERROR("bad mode or failed to add mode\n");
+ return -EINVAL;
+ }
+ drm_mode_set_name(mode);
+ mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
+
+ connector->display_info.width_mm = mode->width_mm;
+ connector->display_info.height_mm = mode->height_mm;
+
+ drm_mode_probed_add(connector, mode);
+
+ return 1; /* Number of modes */
+}
+
+static const struct drm_panel_funcs acx424akp_drm_funcs = {
+ .disable = acx424akp_disable,
+ .unprepare = acx424akp_unprepare,
+ .prepare = acx424akp_prepare,
+ .enable = acx424akp_enable,
+ .get_modes = acx424akp_get_modes,
+};
+
+static int acx424akp_probe(struct mipi_dsi_device *dsi)
+{
+ struct device *dev = &dsi->dev;
+ struct acx424akp *acx;
+ int ret;
+
+ acx = devm_kzalloc(dev, sizeof(struct acx424akp), GFP_KERNEL);
+ if (!acx)
+ return -ENOMEM;
+ acx->video_mode = of_property_read_bool(dev->of_node,
+ "enforce-video-mode");
+
+ mipi_dsi_set_drvdata(dsi, acx);
+ acx->dev = dev;
+
+ dsi->lanes = 2;
+ dsi->format = MIPI_DSI_FMT_RGB888;
+ /*
+ * FIXME: these come from the ST-Ericsson vendor driver for the
+ * HREF520 and seems to reflect limitations in the PLLs on that
+ * platform, if you have the datasheet, please cross-check the
+ * actual max rates.
+ */
+ dsi->lp_rate = 19200000;
+ dsi->hs_rate = 420160000;
+
+ if (acx->video_mode)
+ /* Burst mode using event for sync */
+ dsi->mode_flags =
+ MIPI_DSI_MODE_VIDEO |
+ MIPI_DSI_MODE_VIDEO_BURST;
+ else
+ dsi->mode_flags =
+ MIPI_DSI_CLOCK_NON_CONTINUOUS |
+ MIPI_DSI_MODE_EOT_PACKET;
+
+ acx->supply = devm_regulator_get(dev, "vddi");
+ if (IS_ERR(acx->supply))
+ return PTR_ERR(acx->supply);
+
+ /* This asserts RESET by default */
+ acx->reset_gpio = devm_gpiod_get_optional(dev, "reset",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(acx->reset_gpio)) {
+ ret = PTR_ERR(acx->reset_gpio);
+ if (ret != -EPROBE_DEFER)
+ DRM_DEV_ERROR(dev, "failed to request GPIO (%d)\n",
+ ret);
+ return ret;
+ }
+
+ drm_panel_init(&acx->panel, dev, &acx424akp_drm_funcs,
+ DRM_MODE_CONNECTOR_DSI);
+
+ acx->bl = devm_backlight_device_register(dev, "acx424akp", dev, acx,
+ &acx424akp_bl_ops, NULL);
+ if (IS_ERR(acx->bl)) {
+ DRM_DEV_ERROR(dev, "failed to register backlight device\n");
+ return PTR_ERR(acx->bl);
+ }
+ acx->bl->props.max_brightness = 1023;
+ acx->bl->props.brightness = 512;
+ acx->bl->props.power = FB_BLANK_POWERDOWN;
+
+ ret = drm_panel_add(&acx->panel);
+ if (ret < 0)
+ return ret;
+
+ ret = mipi_dsi_attach(dsi);
+ if (ret < 0) {
+ drm_panel_remove(&acx->panel);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int acx424akp_remove(struct mipi_dsi_device *dsi)
+{
+ struct acx424akp *acx = mipi_dsi_get_drvdata(dsi);
+
+ mipi_dsi_detach(dsi);
+ drm_panel_remove(&acx->panel);
+
+ return 0;
+}
+
+static const struct of_device_id acx424akp_of_match[] = {
+ { .compatible = "sony,acx424akp" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, acx424akp_of_match);
+
+static struct mipi_dsi_driver acx424akp_driver = {
+ .probe = acx424akp_probe,
+ .remove = acx424akp_remove,
+ .driver = {
+ .name = "panel-sony-acx424akp",
+ .of_match_table = acx424akp_of_match,
+ },
+};
+module_mipi_dsi_driver(acx424akp_driver);
+
+MODULE_AUTHOR("Linus Wallei <linus.walleij@linaro.org>");
+MODULE_DESCRIPTION("MIPI-DSI Sony acx424akp Panel Driver");
+MODULE_LICENSE("GPL v2");