diff mbox

[22/27] OMAPDSS: Add new DSI Command Mode panel driver

Message ID 1369906580-27585-23-git-send-email-tomi.valkeinen@ti.com (mailing list archive)
State New, archived
Headers show

Commit Message

Tomi Valkeinen May 30, 2013, 9:36 a.m. UTC
Add DSI Command Mode panel driver which uses the new DSS device model
and DSS ops. This driver only supports a very basic set of features
which should be common to all DSI command mode panels.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
---
 drivers/video/omap2/displays-new/Kconfig        |    5 +
 drivers/video/omap2/displays-new/Makefile       |    1 +
 drivers/video/omap2/displays-new/panel-dsi-cm.c | 1336 +++++++++++++++++++++++
 3 files changed, 1342 insertions(+)
 create mode 100644 drivers/video/omap2/displays-new/panel-dsi-cm.c
diff mbox

Patch

diff --git a/drivers/video/omap2/displays-new/Kconfig b/drivers/video/omap2/displays-new/Kconfig
index 1435f2f..c899d5a 100644
--- a/drivers/video/omap2/displays-new/Kconfig
+++ b/drivers/video/omap2/displays-new/Kconfig
@@ -33,4 +33,9 @@  config PANEL_DPI
 	help
 	  Driver for generic DPI panels.
 
+config PANEL_DSI_CM
+	tristate "Generic DSI Command Mode Panel"
+	help
+	  Driver for generic DSI command mode panels.
+
 endmenu
diff --git a/drivers/video/omap2/displays-new/Makefile b/drivers/video/omap2/displays-new/Makefile
index 54002d3..2e72ac3 100644
--- a/drivers/video/omap2/displays-new/Makefile
+++ b/drivers/video/omap2/displays-new/Makefile
@@ -4,3 +4,4 @@  obj-$(CONFIG_DISPLAY_CONNECTOR_DVI) += connector-dvi.o
 obj-$(CONFIG_DISPLAY_CONNECTOR_HDMI) += connector-hdmi.o
 obj-$(CONFIG_DISPLAY_CONNECTOR_ANALOG_TV) += connector-analog-tv.o
 obj-$(CONFIG_PANEL_DPI) += panel-dpi.o
+obj-$(CONFIG_PANEL_DSI_CM) += panel-dsi-cm.o
diff --git a/drivers/video/omap2/displays-new/panel-dsi-cm.c b/drivers/video/omap2/displays-new/panel-dsi-cm.c
new file mode 100644
index 0000000..48af47d
--- /dev/null
+++ b/drivers/video/omap2/displays-new/panel-dsi-cm.c
@@ -0,0 +1,1336 @@ 
+/*
+ * Generic DSI Command Mode panel driver
+ *
+ * Copyright (C) 2013 Texas Instruments
+ * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
+ *
+ * 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.
+ */
+
+/* #define DEBUG */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/fb.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+
+#include <video/omapdss.h>
+#include <video/omap-panel-data.h>
+#include <video/mipi_display.h>
+
+/* DSI Virtual channel. Hardcoded for now. */
+#define TCH 0
+
+#define DCS_READ_NUM_ERRORS	0x05
+#define DCS_BRIGHTNESS		0x51
+#define DCS_CTRL_DISPLAY	0x53
+#define DCS_GET_ID1		0xda
+#define DCS_GET_ID2		0xdb
+#define DCS_GET_ID3		0xdc
+
+struct panel_drv_data {
+	struct omap_dss_device dssdev;
+	struct omap_dss_device *in;
+
+	struct omap_video_timings timings;
+
+	struct platform_device *pdev;
+
+	struct mutex lock;
+
+	struct backlight_device *bldev;
+
+	unsigned long	hw_guard_end;	/* next value of jiffies when we can
+					 * issue the next sleep in/out command
+					 */
+	unsigned long	hw_guard_wait;	/* max guard time in jiffies */
+
+	/* panel HW configuration from DT or platform data */
+	int reset_gpio;
+	int ext_te_gpio;
+
+	bool use_dsi_backlight;
+
+	struct omap_dsi_pin_config pin_config;
+
+	/* runtime variables */
+	bool enabled;
+
+	bool te_enabled;
+
+	atomic_t do_update;
+	int channel;
+
+	struct delayed_work te_timeout_work;
+
+	bool intro_printed;
+
+	struct workqueue_struct *workqueue;
+
+	bool ulps_enabled;
+	unsigned ulps_timeout;
+	struct delayed_work ulps_work;
+};
+
+#define to_panel_data(p) container_of(p, struct panel_drv_data, dssdev)
+
+static irqreturn_t dsicm_te_isr(int irq, void *data);
+static void dsicm_te_timeout_work_callback(struct work_struct *work);
+static int _dsicm_enable_te(struct panel_drv_data *ddata, bool enable);
+
+static int dsicm_panel_reset(struct panel_drv_data *ddata);
+
+static void dsicm_ulps_work(struct work_struct *work);
+
+static void hw_guard_start(struct panel_drv_data *ddata, int guard_msec)
+{
+	ddata->hw_guard_wait = msecs_to_jiffies(guard_msec);
+	ddata->hw_guard_end = jiffies + ddata->hw_guard_wait;
+}
+
+static void hw_guard_wait(struct panel_drv_data *ddata)
+{
+	unsigned long wait = ddata->hw_guard_end - jiffies;
+
+	if ((long)wait > 0 && wait <= ddata->hw_guard_wait) {
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		schedule_timeout(wait);
+	}
+}
+
+static int dsicm_dcs_read_1(struct panel_drv_data *ddata, u8 dcs_cmd, u8 *data)
+{
+	struct omap_dss_device *in = ddata->in;
+	int r;
+	u8 buf[1];
+
+	r = in->ops.dsi->dcs_read(in, ddata->channel, dcs_cmd, buf, 1);
+
+	if (r < 0)
+		return r;
+
+	*data = buf[0];
+
+	return 0;
+}
+
+static int dsicm_dcs_write_0(struct panel_drv_data *ddata, u8 dcs_cmd)
+{
+	struct omap_dss_device *in = ddata->in;
+	return in->ops.dsi->dcs_write(in, ddata->channel, &dcs_cmd, 1);
+}
+
+static int dsicm_dcs_write_1(struct panel_drv_data *ddata, u8 dcs_cmd, u8 param)
+{
+	struct omap_dss_device *in = ddata->in;
+	u8 buf[2] = { dcs_cmd, param };
+
+	return in->ops.dsi->dcs_write(in, ddata->channel, buf, 2);
+}
+
+static int dsicm_sleep_in(struct panel_drv_data *ddata)
+
+{
+	struct omap_dss_device *in = ddata->in;
+	u8 cmd;
+	int r;
+
+	hw_guard_wait(ddata);
+
+	cmd = MIPI_DCS_ENTER_SLEEP_MODE;
+	r = in->ops.dsi->dcs_write_nosync(in, ddata->channel, &cmd, 1);
+	if (r)
+		return r;
+
+	hw_guard_start(ddata, 120);
+
+	msleep(5);
+
+	return 0;
+}
+
+static int dsicm_sleep_out(struct panel_drv_data *ddata)
+{
+	int r;
+
+	hw_guard_wait(ddata);
+
+	r = dsicm_dcs_write_0(ddata, MIPI_DCS_EXIT_SLEEP_MODE);
+	if (r)
+		return r;
+
+	hw_guard_start(ddata, 120);
+
+	msleep(5);
+
+	return 0;
+}
+
+static int dsicm_get_id(struct panel_drv_data *ddata, u8 *id1, u8 *id2, u8 *id3)
+{
+	int r;
+
+	r = dsicm_dcs_read_1(ddata, DCS_GET_ID1, id1);
+	if (r)
+		return r;
+	r = dsicm_dcs_read_1(ddata, DCS_GET_ID2, id2);
+	if (r)
+		return r;
+	r = dsicm_dcs_read_1(ddata, DCS_GET_ID3, id3);
+	if (r)
+		return r;
+
+	return 0;
+}
+
+static int dsicm_set_update_window(struct panel_drv_data *ddata,
+		u16 x, u16 y, u16 w, u16 h)
+{
+	struct omap_dss_device *in = ddata->in;
+	int r;
+	u16 x1 = x;
+	u16 x2 = x + w - 1;
+	u16 y1 = y;
+	u16 y2 = y + h - 1;
+
+	u8 buf[5];
+	buf[0] = MIPI_DCS_SET_COLUMN_ADDRESS;
+	buf[1] = (x1 >> 8) & 0xff;
+	buf[2] = (x1 >> 0) & 0xff;
+	buf[3] = (x2 >> 8) & 0xff;
+	buf[4] = (x2 >> 0) & 0xff;
+
+	r = in->ops.dsi->dcs_write_nosync(in, ddata->channel, buf, sizeof(buf));
+	if (r)
+		return r;
+
+	buf[0] = MIPI_DCS_SET_PAGE_ADDRESS;
+	buf[1] = (y1 >> 8) & 0xff;
+	buf[2] = (y1 >> 0) & 0xff;
+	buf[3] = (y2 >> 8) & 0xff;
+	buf[4] = (y2 >> 0) & 0xff;
+
+	r = in->ops.dsi->dcs_write_nosync(in, ddata->channel, buf, sizeof(buf));
+	if (r)
+		return r;
+
+	in->ops.dsi->bta_sync(in, ddata->channel);
+
+	return r;
+}
+
+static void dsicm_queue_ulps_work(struct panel_drv_data *ddata)
+{
+	if (ddata->ulps_timeout > 0)
+		queue_delayed_work(ddata->workqueue, &ddata->ulps_work,
+				msecs_to_jiffies(ddata->ulps_timeout));
+}
+
+static void dsicm_cancel_ulps_work(struct panel_drv_data *ddata)
+{
+	cancel_delayed_work(&ddata->ulps_work);
+}
+
+static int dsicm_enter_ulps(struct panel_drv_data *ddata)
+{
+	struct omap_dss_device *in = ddata->in;
+	int r;
+
+	if (ddata->ulps_enabled)
+		return 0;
+
+	dsicm_cancel_ulps_work(ddata);
+
+	r = _dsicm_enable_te(ddata, false);
+	if (r)
+		goto err;
+
+	if (gpio_is_valid(ddata->ext_te_gpio))
+		disable_irq(gpio_to_irq(ddata->ext_te_gpio));
+
+	in->ops.dsi->disable(in, false, true);
+
+	ddata->ulps_enabled = true;
+
+	return 0;
+
+err:
+	dev_err(&ddata->pdev->dev, "enter ULPS failed");
+	dsicm_panel_reset(ddata);
+
+	ddata->ulps_enabled = false;
+
+	dsicm_queue_ulps_work(ddata);
+
+	return r;
+}
+
+static int dsicm_exit_ulps(struct panel_drv_data *ddata)
+{
+	struct omap_dss_device *in = ddata->in;
+	int r;
+
+	if (!ddata->ulps_enabled)
+		return 0;
+
+	r = in->ops.dsi->enable(in);
+	if (r) {
+		dev_err(&ddata->pdev->dev, "failed to enable DSI\n");
+		goto err1;
+	}
+
+	in->ops.dsi->enable_hs(in, ddata->channel, true);
+
+	r = _dsicm_enable_te(ddata, true);
+	if (r) {
+		dev_err(&ddata->pdev->dev, "failed to re-enable TE");
+		goto err2;
+	}
+
+	if (gpio_is_valid(ddata->ext_te_gpio))
+		enable_irq(gpio_to_irq(ddata->ext_te_gpio));
+
+	dsicm_queue_ulps_work(ddata);
+
+	ddata->ulps_enabled = false;
+
+	return 0;
+
+err2:
+	dev_err(&ddata->pdev->dev, "failed to exit ULPS");
+
+	r = dsicm_panel_reset(ddata);
+	if (!r) {
+		if (gpio_is_valid(ddata->ext_te_gpio))
+			enable_irq(gpio_to_irq(ddata->ext_te_gpio));
+		ddata->ulps_enabled = false;
+	}
+err1:
+	dsicm_queue_ulps_work(ddata);
+
+	return r;
+}
+
+static int dsicm_wake_up(struct panel_drv_data *ddata)
+{
+	if (ddata->ulps_enabled)
+		return dsicm_exit_ulps(ddata);
+
+	dsicm_cancel_ulps_work(ddata);
+	dsicm_queue_ulps_work(ddata);
+	return 0;
+}
+
+static int dsicm_bl_update_status(struct backlight_device *dev)
+{
+	struct panel_drv_data *ddata = dev_get_drvdata(&dev->dev);
+	struct omap_dss_device *in = ddata->in;
+	int r;
+	int level;
+
+	if (dev->props.fb_blank == FB_BLANK_UNBLANK &&
+			dev->props.power == FB_BLANK_UNBLANK)
+		level = dev->props.brightness;
+	else
+		level = 0;
+
+	dev_dbg(&ddata->pdev->dev, "update brightness to %d\n", level);
+
+	mutex_lock(&ddata->lock);
+
+	if (ddata->enabled) {
+		in->ops.dsi->bus_lock(in);
+
+		r = dsicm_wake_up(ddata);
+		if (!r)
+			r = dsicm_dcs_write_1(ddata, DCS_BRIGHTNESS, level);
+
+		in->ops.dsi->bus_unlock(in);
+	} else {
+		r = 0;
+	}
+
+	mutex_unlock(&ddata->lock);
+
+	return r;
+}
+
+static int dsicm_bl_get_intensity(struct backlight_device *dev)
+{
+	if (dev->props.fb_blank == FB_BLANK_UNBLANK &&
+			dev->props.power == FB_BLANK_UNBLANK)
+		return dev->props.brightness;
+
+	return 0;
+}
+
+static const struct backlight_ops dsicm_bl_ops = {
+	.get_brightness = dsicm_bl_get_intensity,
+	.update_status  = dsicm_bl_update_status,
+};
+
+static void dsicm_get_resolution(struct omap_dss_device *dssdev,
+		u16 *xres, u16 *yres)
+{
+	*xres = dssdev->panel.timings.x_res;
+	*yres = dssdev->panel.timings.y_res;
+}
+
+static ssize_t dsicm_num_errors_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
+	struct omap_dss_device *in = ddata->in;
+	u8 errors = 0;
+	int r;
+
+	mutex_lock(&ddata->lock);
+
+	if (ddata->enabled) {
+		in->ops.dsi->bus_lock(in);
+
+		r = dsicm_wake_up(ddata);
+		if (!r)
+			r = dsicm_dcs_read_1(ddata, DCS_READ_NUM_ERRORS,
+					&errors);
+
+		in->ops.dsi->bus_unlock(in);
+	} else {
+		r = -ENODEV;
+	}
+
+	mutex_unlock(&ddata->lock);
+
+	if (r)
+		return r;
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", errors);
+}
+
+static ssize_t dsicm_hw_revision_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
+	struct omap_dss_device *in = ddata->in;
+	u8 id1, id2, id3;
+	int r;
+
+	mutex_lock(&ddata->lock);
+
+	if (ddata->enabled) {
+		in->ops.dsi->bus_lock(in);
+
+		r = dsicm_wake_up(ddata);
+		if (!r)
+			r = dsicm_get_id(ddata, &id1, &id2, &id3);
+
+		in->ops.dsi->bus_unlock(in);
+	} else {
+		r = -ENODEV;
+	}
+
+	mutex_unlock(&ddata->lock);
+
+	if (r)
+		return r;
+
+	return snprintf(buf, PAGE_SIZE, "%02x.%02x.%02x\n", id1, id2, id3);
+}
+
+static ssize_t dsicm_store_ulps(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
+	struct omap_dss_device *in = ddata->in;
+	unsigned long t;
+	int r;
+
+	r = kstrtoul(buf, 0, &t);
+	if (r)
+		return r;
+
+	mutex_lock(&ddata->lock);
+
+	if (ddata->enabled) {
+		in->ops.dsi->bus_lock(in);
+
+		if (t)
+			r = dsicm_enter_ulps(ddata);
+		else
+			r = dsicm_wake_up(ddata);
+
+		in->ops.dsi->bus_unlock(in);
+	}
+
+	mutex_unlock(&ddata->lock);
+
+	if (r)
+		return r;
+
+	return count;
+}
+
+static ssize_t dsicm_show_ulps(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
+	unsigned t;
+
+	mutex_lock(&ddata->lock);
+	t = ddata->ulps_enabled;
+	mutex_unlock(&ddata->lock);
+
+	return snprintf(buf, PAGE_SIZE, "%u\n", t);
+}
+
+static ssize_t dsicm_store_ulps_timeout(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf, size_t count)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
+	struct omap_dss_device *in = ddata->in;
+	unsigned long t;
+	int r;
+
+	r = kstrtoul(buf, 0, &t);
+	if (r)
+		return r;
+
+	mutex_lock(&ddata->lock);
+	ddata->ulps_timeout = t;
+
+	if (ddata->enabled) {
+		/* dsicm_wake_up will restart the timer */
+		in->ops.dsi->bus_lock(in);
+		r = dsicm_wake_up(ddata);
+		in->ops.dsi->bus_unlock(in);
+	}
+
+	mutex_unlock(&ddata->lock);
+
+	if (r)
+		return r;
+
+	return count;
+}
+
+static ssize_t dsicm_show_ulps_timeout(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
+	unsigned t;
+
+	mutex_lock(&ddata->lock);
+	t = ddata->ulps_timeout;
+	mutex_unlock(&ddata->lock);
+
+	return snprintf(buf, PAGE_SIZE, "%u\n", t);
+}
+
+static DEVICE_ATTR(num_dsi_errors, S_IRUGO, dsicm_num_errors_show, NULL);
+static DEVICE_ATTR(hw_revision, S_IRUGO, dsicm_hw_revision_show, NULL);
+static DEVICE_ATTR(ulps, S_IRUGO | S_IWUSR,
+		dsicm_show_ulps, dsicm_store_ulps);
+static DEVICE_ATTR(ulps_timeout, S_IRUGO | S_IWUSR,
+		dsicm_show_ulps_timeout, dsicm_store_ulps_timeout);
+
+static struct attribute *dsicm_attrs[] = {
+	&dev_attr_num_dsi_errors.attr,
+	&dev_attr_hw_revision.attr,
+	&dev_attr_ulps.attr,
+	&dev_attr_ulps_timeout.attr,
+	NULL,
+};
+
+static struct attribute_group dsicm_attr_group = {
+	.attrs = dsicm_attrs,
+};
+
+static void dsicm_hw_reset(struct panel_drv_data *ddata)
+{
+	if (!gpio_is_valid(ddata->reset_gpio))
+		return;
+
+	gpio_set_value(ddata->reset_gpio, 1);
+	udelay(10);
+	/* reset the panel */
+	gpio_set_value(ddata->reset_gpio, 0);
+	/* assert reset */
+	udelay(10);
+	gpio_set_value(ddata->reset_gpio, 1);
+	/* wait after releasing reset */
+	msleep(5);
+}
+
+static int dsicm_power_on(struct panel_drv_data *ddata)
+{
+	struct omap_dss_device *in = ddata->in;
+	u8 id1, id2, id3;
+	int r;
+	struct omap_dss_dsi_config dsi_config = {
+		.mode = OMAP_DSS_DSI_CMD_MODE,
+		.pixel_format = OMAP_DSS_DSI_FMT_RGB888,
+		.timings = &ddata->timings,
+		.hs_clk_min = 150000000,
+		.hs_clk_max = 300000000,
+		.lp_clk_min = 7000000,
+		.lp_clk_max = 10000000,
+	};
+
+	r = in->ops.dsi->configure_pins(in, &ddata->pin_config);
+	if (r) {
+		dev_err(&ddata->pdev->dev, "failed to configure DSI pins\n");
+		goto err0;
+	};
+
+	r = in->ops.dsi->set_config(in, &dsi_config);
+	if (r) {
+		dev_err(&ddata->pdev->dev, "failed to configure DSI\n");
+		goto err0;
+	}
+
+	r = in->ops.dsi->enable(in);
+	if (r) {
+		dev_err(&ddata->pdev->dev, "failed to enable DSI\n");
+		goto err0;
+	}
+
+	dsicm_hw_reset(ddata);
+
+	in->ops.dsi->enable_hs(in, ddata->channel, false);
+
+	r = dsicm_sleep_out(ddata);
+	if (r)
+		goto err;
+
+	r = dsicm_get_id(ddata, &id1, &id2, &id3);
+	if (r)
+		goto err;
+
+	r = dsicm_dcs_write_1(ddata, DCS_BRIGHTNESS, 0xff);
+	if (r)
+		goto err;
+
+	r = dsicm_dcs_write_1(ddata, DCS_CTRL_DISPLAY,
+			(1<<2) | (1<<5));	/* BL | BCTRL */
+	if (r)
+		goto err;
+
+	r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_PIXEL_FORMAT,
+		MIPI_DCS_PIXEL_FMT_24BIT);
+	if (r)
+		goto err;
+
+	r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_DISPLAY_ON);
+	if (r)
+		goto err;
+
+	r = _dsicm_enable_te(ddata, ddata->te_enabled);
+	if (r)
+		goto err;
+
+	r = in->ops.dsi->enable_video_output(in, ddata->channel);
+	if (r)
+		goto err;
+
+	ddata->enabled = 1;
+
+	if (!ddata->intro_printed) {
+		dev_info(&ddata->pdev->dev, "panel revision %02x.%02x.%02x\n",
+			id1, id2, id3);
+		ddata->intro_printed = true;
+	}
+
+	in->ops.dsi->enable_hs(in, ddata->channel, true);
+
+	return 0;
+err:
+	dev_err(&ddata->pdev->dev, "error while enabling panel, issuing HW reset\n");
+
+	dsicm_hw_reset(ddata);
+
+	in->ops.dsi->disable(in, true, false);
+err0:
+	return r;
+}
+
+static void dsicm_power_off(struct panel_drv_data *ddata)
+{
+	struct omap_dss_device *in = ddata->in;
+	int r;
+
+	in->ops.dsi->disable_video_output(in, ddata->channel);
+
+	r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_DISPLAY_OFF);
+	if (!r)
+		r = dsicm_sleep_in(ddata);
+
+	if (r) {
+		dev_err(&ddata->pdev->dev,
+				"error disabling panel, issuing HW reset\n");
+		dsicm_hw_reset(ddata);
+	}
+
+	in->ops.dsi->disable(in, true, false);
+
+	ddata->enabled = 0;
+}
+
+static int dsicm_panel_reset(struct panel_drv_data *ddata)
+{
+	dev_err(&ddata->pdev->dev, "performing LCD reset\n");
+
+	dsicm_power_off(ddata);
+	dsicm_hw_reset(ddata);
+	return dsicm_power_on(ddata);
+}
+
+static int dsicm_connect(struct omap_dss_device *dssdev)
+{
+	struct panel_drv_data *ddata = to_panel_data(dssdev);
+	struct omap_dss_device *in = ddata->in;
+	struct device *dev = &ddata->pdev->dev;
+	int r;
+
+	if (omapdss_device_is_connected(dssdev))
+		return 0;
+
+	r = in->ops.dsi->connect(in, dssdev);
+	if (r) {
+		dev_err(dev, "Failed to connect to video source\n");
+		return r;
+	}
+
+	r = in->ops.dsi->request_vc(ddata->in, &ddata->channel);
+	if (r) {
+		dev_err(dev, "failed to get virtual channel\n");
+		goto err_req_vc;
+	}
+
+	r = in->ops.dsi->set_vc_id(ddata->in, ddata->channel, TCH);
+	if (r) {
+		dev_err(dev, "failed to set VC_ID\n");
+		goto err_vc_id;
+	}
+
+	return 0;
+
+err_vc_id:
+	in->ops.dsi->release_vc(ddata->in, ddata->channel);
+err_req_vc:
+	in->ops.dsi->disconnect(in, dssdev);
+	return r;
+}
+
+static void dsicm_disconnect(struct omap_dss_device *dssdev)
+{
+	struct panel_drv_data *ddata = to_panel_data(dssdev);
+	struct omap_dss_device *in = ddata->in;
+
+	if (!omapdss_device_is_connected(dssdev))
+		return;
+
+	in->ops.dsi->release_vc(in, ddata->channel);
+	in->ops.dsi->disconnect(in, dssdev);
+}
+
+static int dsicm_enable(struct omap_dss_device *dssdev)
+{
+	struct panel_drv_data *ddata = to_panel_data(dssdev);
+	struct omap_dss_device *in = ddata->in;
+	int r;
+
+	dev_dbg(&ddata->pdev->dev, "enable\n");
+
+	mutex_lock(&ddata->lock);
+
+	if (!omapdss_device_is_connected(dssdev)) {
+		r = -ENODEV;
+		goto err;
+	}
+
+	if (omapdss_device_is_enabled(dssdev)) {
+		r = 0;
+		goto err;
+	}
+
+	in->ops.dsi->bus_lock(in);
+
+	r = dsicm_power_on(ddata);
+
+	in->ops.dsi->bus_unlock(in);
+
+	if (r)
+		goto err;
+
+	dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
+
+	mutex_unlock(&ddata->lock);
+
+	return 0;
+err:
+	dev_dbg(&ddata->pdev->dev, "enable failed\n");
+	mutex_unlock(&ddata->lock);
+	return r;
+}
+
+static void dsicm_disable(struct omap_dss_device *dssdev)
+{
+	struct panel_drv_data *ddata = to_panel_data(dssdev);
+	struct omap_dss_device *in = ddata->in;
+	int r;
+
+	dev_dbg(&ddata->pdev->dev, "disable\n");
+
+	mutex_lock(&ddata->lock);
+
+	dsicm_cancel_ulps_work(ddata);
+
+	in->ops.dsi->bus_lock(in);
+
+	if (omapdss_device_is_enabled(dssdev)) {
+		r = dsicm_wake_up(ddata);
+		if (!r)
+			dsicm_power_off(ddata);
+	}
+
+	in->ops.dsi->bus_unlock(in);
+
+	dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
+
+	mutex_unlock(&ddata->lock);
+}
+
+static void dsicm_framedone_cb(int err, void *data)
+{
+	struct panel_drv_data *ddata = data;
+	struct omap_dss_device *in = ddata->in;
+
+	dev_dbg(&ddata->pdev->dev, "framedone, err %d\n", err);
+	in->ops.dsi->bus_unlock(ddata->in);
+}
+
+static irqreturn_t dsicm_te_isr(int irq, void *data)
+{
+	struct panel_drv_data *ddata = data;
+	struct omap_dss_device *in = ddata->in;
+	int old;
+	int r;
+
+	old = atomic_cmpxchg(&ddata->do_update, 1, 0);
+
+	if (old) {
+		cancel_delayed_work(&ddata->te_timeout_work);
+
+		r = in->ops.dsi->update(in, ddata->channel, dsicm_framedone_cb,
+				ddata);
+		if (r)
+			goto err;
+	}
+
+	return IRQ_HANDLED;
+err:
+	dev_err(&ddata->pdev->dev, "start update failed\n");
+	in->ops.dsi->bus_unlock(in);
+	return IRQ_HANDLED;
+}
+
+static void dsicm_te_timeout_work_callback(struct work_struct *work)
+{
+	struct panel_drv_data *ddata = container_of(work, struct panel_drv_data,
+					te_timeout_work.work);
+	struct omap_dss_device *in = ddata->in;
+
+	dev_err(&ddata->pdev->dev, "TE not received for 250ms!\n");
+
+	atomic_set(&ddata->do_update, 0);
+	in->ops.dsi->bus_unlock(in);
+}
+
+static int dsicm_update(struct omap_dss_device *dssdev,
+				    u16 x, u16 y, u16 w, u16 h)
+{
+	struct panel_drv_data *ddata = to_panel_data(dssdev);
+	struct omap_dss_device *in = ddata->in;
+	int r;
+
+	dev_dbg(&ddata->pdev->dev, "update %d, %d, %d x %d\n", x, y, w, h);
+
+	mutex_lock(&ddata->lock);
+	in->ops.dsi->bus_lock(in);
+
+	r = dsicm_wake_up(ddata);
+	if (r)
+		goto err;
+
+	if (!ddata->enabled) {
+		r = 0;
+		goto err;
+	}
+
+	/* XXX no need to send this every frame, but dsi break if not done */
+	r = dsicm_set_update_window(ddata, 0, 0,
+			dssdev->panel.timings.x_res,
+			dssdev->panel.timings.y_res);
+	if (r)
+		goto err;
+
+	if (ddata->te_enabled && gpio_is_valid(ddata->ext_te_gpio)) {
+		schedule_delayed_work(&ddata->te_timeout_work,
+				msecs_to_jiffies(250));
+		atomic_set(&ddata->do_update, 1);
+	} else {
+		r = in->ops.dsi->update(in, ddata->channel, dsicm_framedone_cb,
+				ddata);
+		if (r)
+			goto err;
+	}
+
+	/* note: no bus_unlock here. unlock is in framedone_cb */
+	mutex_unlock(&ddata->lock);
+	return 0;
+err:
+	in->ops.dsi->bus_unlock(in);
+	mutex_unlock(&ddata->lock);
+	return r;
+}
+
+static int dsicm_sync(struct omap_dss_device *dssdev)
+{
+	struct panel_drv_data *ddata = to_panel_data(dssdev);
+	struct omap_dss_device *in = ddata->in;
+
+	dev_dbg(&ddata->pdev->dev, "sync\n");
+
+	mutex_lock(&ddata->lock);
+	in->ops.dsi->bus_lock(in);
+	in->ops.dsi->bus_unlock(in);
+	mutex_unlock(&ddata->lock);
+
+	dev_dbg(&ddata->pdev->dev, "sync done\n");
+
+	return 0;
+}
+
+static int _dsicm_enable_te(struct panel_drv_data *ddata, bool enable)
+{
+	struct omap_dss_device *in = ddata->in;
+	int r;
+
+	if (enable)
+		r = dsicm_dcs_write_1(ddata, MIPI_DCS_SET_TEAR_ON, 0);
+	else
+		r = dsicm_dcs_write_0(ddata, MIPI_DCS_SET_TEAR_OFF);
+
+	if (!gpio_is_valid(ddata->ext_te_gpio))
+		in->ops.dsi->enable_te(in, enable);
+
+	/* possible panel bug */
+	msleep(100);
+
+	return r;
+}
+
+static int dsicm_enable_te(struct omap_dss_device *dssdev, bool enable)
+{
+	struct panel_drv_data *ddata = to_panel_data(dssdev);
+	struct omap_dss_device *in = ddata->in;
+	int r;
+
+	mutex_lock(&ddata->lock);
+
+	if (ddata->te_enabled == enable)
+		goto end;
+
+	in->ops.dsi->bus_lock(in);
+
+	if (ddata->enabled) {
+		r = dsicm_wake_up(ddata);
+		if (r)
+			goto err;
+
+		r = _dsicm_enable_te(ddata, enable);
+		if (r)
+			goto err;
+	}
+
+	ddata->te_enabled = enable;
+
+	in->ops.dsi->bus_unlock(in);
+end:
+	mutex_unlock(&ddata->lock);
+
+	return 0;
+err:
+	in->ops.dsi->bus_unlock(in);
+	mutex_unlock(&ddata->lock);
+
+	return r;
+}
+
+static int dsicm_get_te(struct omap_dss_device *dssdev)
+{
+	struct panel_drv_data *ddata = to_panel_data(dssdev);
+	int r;
+
+	mutex_lock(&ddata->lock);
+	r = ddata->te_enabled;
+	mutex_unlock(&ddata->lock);
+
+	return r;
+}
+
+static int dsicm_memory_read(struct omap_dss_device *dssdev,
+		void *buf, size_t size,
+		u16 x, u16 y, u16 w, u16 h)
+{
+	struct panel_drv_data *ddata = to_panel_data(dssdev);
+	struct omap_dss_device *in = ddata->in;
+	int r;
+	int first = 1;
+	int plen;
+	unsigned buf_used = 0;
+
+	if (size < w * h * 3)
+		return -ENOMEM;
+
+	mutex_lock(&ddata->lock);
+
+	if (!ddata->enabled) {
+		r = -ENODEV;
+		goto err1;
+	}
+
+	size = min(w * h * 3,
+			dssdev->panel.timings.x_res *
+			dssdev->panel.timings.y_res * 3);
+
+	in->ops.dsi->bus_lock(in);
+
+	r = dsicm_wake_up(ddata);
+	if (r)
+		goto err2;
+
+	/* plen 1 or 2 goes into short packet. until checksum error is fixed,
+	 * use short packets. plen 32 works, but bigger packets seem to cause
+	 * an error. */
+	if (size % 2)
+		plen = 1;
+	else
+		plen = 2;
+
+	dsicm_set_update_window(ddata, x, y, w, h);
+
+	r = in->ops.dsi->set_max_rx_packet_size(in, ddata->channel, plen);
+	if (r)
+		goto err2;
+
+	while (buf_used < size) {
+		u8 dcs_cmd = first ? 0x2e : 0x3e;
+		first = 0;
+
+		r = in->ops.dsi->dcs_read(in, ddata->channel, dcs_cmd,
+				buf + buf_used, size - buf_used);
+
+		if (r < 0) {
+			dev_err(dssdev->dev, "read error\n");
+			goto err3;
+		}
+
+		buf_used += r;
+
+		if (r < plen) {
+			dev_err(&ddata->pdev->dev, "short read\n");
+			break;
+		}
+
+		if (signal_pending(current)) {
+			dev_err(&ddata->pdev->dev, "signal pending, "
+					"aborting memory read\n");
+			r = -ERESTARTSYS;
+			goto err3;
+		}
+	}
+
+	r = buf_used;
+
+err3:
+	in->ops.dsi->set_max_rx_packet_size(in, ddata->channel, 1);
+err2:
+	in->ops.dsi->bus_unlock(in);
+err1:
+	mutex_unlock(&ddata->lock);
+	return r;
+}
+
+static void dsicm_ulps_work(struct work_struct *work)
+{
+	struct panel_drv_data *ddata = container_of(work, struct panel_drv_data,
+			ulps_work.work);
+	struct omap_dss_device *dssdev = &ddata->dssdev;
+	struct omap_dss_device *in = ddata->in;
+
+	mutex_lock(&ddata->lock);
+
+	if (dssdev->state != OMAP_DSS_DISPLAY_ACTIVE || !ddata->enabled) {
+		mutex_unlock(&ddata->lock);
+		return;
+	}
+
+	in->ops.dsi->bus_lock(in);
+
+	dsicm_enter_ulps(ddata);
+
+	in->ops.dsi->bus_unlock(in);
+	mutex_unlock(&ddata->lock);
+}
+
+static struct omap_dss_driver dsicm_ops = {
+	.connect	= dsicm_connect,
+	.disconnect	= dsicm_disconnect,
+
+	.enable		= dsicm_enable,
+	.disable	= dsicm_disable,
+
+	.update		= dsicm_update,
+	.sync		= dsicm_sync,
+
+	.get_resolution	= dsicm_get_resolution,
+	.get_recommended_bpp = omapdss_default_get_recommended_bpp,
+
+	.enable_te	= dsicm_enable_te,
+	.get_te		= dsicm_get_te,
+
+	.memory_read	= dsicm_memory_read,
+};
+
+static int dsicm_probe_pdata(struct platform_device *pdev)
+{
+	const struct panel_dsicm_platform_data *pdata;
+	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
+	struct omap_dss_device *dssdev, *in;
+
+	pdata = dev_get_platdata(&pdev->dev);
+
+	in = omap_dss_find_output(pdata->source);
+	if (in == NULL) {
+		dev_err(&pdev->dev, "failed to find video source\n");
+		return -EPROBE_DEFER;
+	}
+	ddata->in = in;
+
+	ddata->reset_gpio = pdata->reset_gpio;
+
+	if (pdata->use_ext_te)
+		ddata->ext_te_gpio = pdata->ext_te_gpio;
+	else
+		ddata->ext_te_gpio = -1;
+
+	ddata->ulps_timeout = pdata->ulps_timeout;
+
+	ddata->use_dsi_backlight = pdata->use_dsi_backlight;
+
+	ddata->pin_config = pdata->pin_config;
+
+	dssdev = &ddata->dssdev;
+	dssdev->name = pdata->name;
+
+	return 0;
+}
+
+static int dsicm_probe(struct platform_device *pdev)
+{
+	struct backlight_properties props;
+	struct panel_drv_data *ddata;
+	struct backlight_device *bldev = NULL;
+	struct device *dev = &pdev->dev;
+	struct omap_dss_device *dssdev;
+	int r;
+
+	dev_dbg(dev, "probe\n");
+
+	ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
+	if (!ddata)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, ddata);
+	ddata->pdev = pdev;
+
+	if (dev_get_platdata(dev)) {
+		r = dsicm_probe_pdata(pdev);
+		if (r)
+			return r;
+	} else {
+		return -ENODEV;
+	}
+
+	ddata->timings.x_res = 864;
+	ddata->timings.y_res = 480;
+	ddata->timings.pixel_clock = DIV_ROUND_UP(864 * 480 * 60, 1000);
+
+	dssdev = &ddata->dssdev;
+	dssdev->dev = dev;
+	dssdev->driver = &dsicm_ops;
+	dssdev->panel.timings = ddata->timings;
+	dssdev->type = OMAP_DISPLAY_TYPE_DSI;
+	dssdev->owner = THIS_MODULE;
+
+	dssdev->panel.dsi_pix_fmt = OMAP_DSS_DSI_FMT_RGB888;
+	dssdev->caps = OMAP_DSS_DISPLAY_CAP_MANUAL_UPDATE |
+		OMAP_DSS_DISPLAY_CAP_TEAR_ELIM;
+
+	r = omapdss_register_display(dssdev);
+	if (r) {
+		dev_err(dev, "Failed to register panel\n");
+		goto err_reg;
+	}
+
+	mutex_init(&ddata->lock);
+
+	atomic_set(&ddata->do_update, 0);
+
+	if (gpio_is_valid(ddata->reset_gpio)) {
+		r = devm_gpio_request_one(dev, ddata->reset_gpio,
+				GPIOF_OUT_INIT_LOW, "taal rst");
+		if (r) {
+			dev_err(dev, "failed to request reset gpio\n");
+			return r;
+		}
+	}
+
+	if (gpio_is_valid(ddata->ext_te_gpio)) {
+		r = devm_gpio_request_one(dev, ddata->ext_te_gpio,
+				GPIOF_IN, "taal irq");
+		if (r) {
+			dev_err(dev, "GPIO request failed\n");
+			return r;
+		}
+
+		r = devm_request_irq(dev, gpio_to_irq(ddata->ext_te_gpio),
+				dsicm_te_isr,
+				IRQF_TRIGGER_RISING,
+				"taal vsync", ddata);
+
+		if (r) {
+			dev_err(dev, "IRQ request failed\n");
+			return r;
+		}
+
+		INIT_DEFERRABLE_WORK(&ddata->te_timeout_work,
+					dsicm_te_timeout_work_callback);
+
+		dev_dbg(dev, "Using GPIO TE\n");
+	}
+
+	ddata->workqueue = create_singlethread_workqueue("dsicm_wq");
+	if (ddata->workqueue == NULL) {
+		dev_err(dev, "can't create workqueue\n");
+		return -ENOMEM;
+	}
+	INIT_DELAYED_WORK(&ddata->ulps_work, dsicm_ulps_work);
+
+	dsicm_hw_reset(ddata);
+
+	if (ddata->use_dsi_backlight) {
+		memset(&props, 0, sizeof(struct backlight_properties));
+		props.max_brightness = 255;
+
+		props.type = BACKLIGHT_RAW;
+		bldev = backlight_device_register(dev_name(dev),
+				dev, ddata, &dsicm_bl_ops, &props);
+		if (IS_ERR(bldev)) {
+			r = PTR_ERR(bldev);
+			goto err_bl;
+		}
+
+		ddata->bldev = bldev;
+
+		bldev->props.fb_blank = FB_BLANK_UNBLANK;
+		bldev->props.power = FB_BLANK_UNBLANK;
+		bldev->props.brightness = 255;
+
+		dsicm_bl_update_status(bldev);
+	}
+
+	r = sysfs_create_group(&dev->kobj, &dsicm_attr_group);
+	if (r) {
+		dev_err(dev, "failed to create sysfs files\n");
+		goto err_sysfs_create;
+	}
+
+	return 0;
+
+err_sysfs_create:
+	if (bldev != NULL)
+		backlight_device_unregister(bldev);
+err_bl:
+	destroy_workqueue(ddata->workqueue);
+err_reg:
+	return r;
+}
+
+static int __exit dsicm_remove(struct platform_device *pdev)
+{
+	struct panel_drv_data *ddata = platform_get_drvdata(pdev);
+	struct omap_dss_device *dssdev = &ddata->dssdev;
+	struct backlight_device *bldev;
+
+	dev_dbg(&pdev->dev, "remove\n");
+
+	omapdss_unregister_display(dssdev);
+
+	dsicm_disable(dssdev);
+	dsicm_disconnect(dssdev);
+
+	sysfs_remove_group(&pdev->dev.kobj, &dsicm_attr_group);
+
+	bldev = ddata->bldev;
+	if (bldev != NULL) {
+		bldev->props.power = FB_BLANK_POWERDOWN;
+		dsicm_bl_update_status(bldev);
+		backlight_device_unregister(bldev);
+	}
+
+	omap_dss_put_device(ddata->in);
+
+	dsicm_cancel_ulps_work(ddata);
+	destroy_workqueue(ddata->workqueue);
+
+	/* reset, to be sure that the panel is in a valid state */
+	dsicm_hw_reset(ddata);
+
+	return 0;
+}
+
+static struct platform_driver dsicm_driver = {
+	.probe = dsicm_probe,
+	.remove = __exit_p(dsicm_remove),
+	.driver = {
+		.name = "panel-dsi-cm",
+		.owner = THIS_MODULE,
+	},
+};
+
+module_platform_driver(dsicm_driver);
+
+MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
+MODULE_DESCRIPTION("Generic DSI Command Mode Panel Driver");
+MODULE_LICENSE("GPL");