linux-zen-server/drivers/gpu/drm/panel/panel-samsung-s6e63m0-dsi.c

// SPDX-License-Identifier: GPL-2.0
/*
 * DSI interface to the Samsung S6E63M0 panel.
 * (C) 2019 Linus Walleij
 */

#include <linux/module.h>
#include <linux/delay.h>
#include <linux/of_device.h>

#include <drm/drm_mipi_dsi.h>
#include <drm/drm_print.h>

#include "panel-samsung-s6e63m0.h"

#define MCS_GLOBAL_PARAM	0xb0
#define S6E63M0_DSI_MAX_CHUNK	15 /* CMD + 15 bytes max */

static int s6e63m0_dsi_dcs_read(struct device *dev, void *trsp,
				const u8 cmd, u8 *data)
{
	struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
	int ret;

	ret = mipi_dsi_dcs_read(dsi, cmd, data, 1);
	if (ret < 0) {
		dev_err(dev, "could not read DCS CMD %02x\n", cmd);
		return ret;
	}

	dev_dbg(dev, "DSI read CMD %02x = %02x\n", cmd, *data);

	return 0;
}

static int s6e63m0_dsi_dcs_write(struct device *dev, void *trsp,
				 const u8 *data, size_t len)
{
	struct mipi_dsi_device *dsi = to_mipi_dsi_device(dev);
	const u8 *seqp = data;
	u8 cmd;
	u8 cmdwritten;
	int remain;
	int chunk;
	int ret;

	dev_dbg(dev, "DSI writing dcs seq: %*ph\n", (int)len, data);

	/* Pick out and skip past the DCS command */
	cmd = *seqp;
	seqp++;
	cmdwritten = 0;
	remain = len - 1;
	chunk = remain;

	/* Send max S6E63M0_DSI_MAX_CHUNK bytes at a time */
	if (chunk > S6E63M0_DSI_MAX_CHUNK)
		chunk = S6E63M0_DSI_MAX_CHUNK;
	ret = mipi_dsi_dcs_write(dsi, cmd, seqp, chunk);
	if (ret < 0) {
		dev_err(dev, "error sending DCS command seq cmd %02x\n", cmd);
		return ret;
	}
	cmdwritten += chunk;
	seqp += chunk;

	while (cmdwritten < remain) {
		chunk = remain - cmdwritten;
		if (chunk > S6E63M0_DSI_MAX_CHUNK)
			chunk = S6E63M0_DSI_MAX_CHUNK;
		ret = mipi_dsi_dcs_write(dsi, MCS_GLOBAL_PARAM, &cmdwritten, 1);
		if (ret < 0) {
			dev_err(dev, "error sending CMD %02x global param %02x\n",
				cmd, cmdwritten);
			return ret;
		}
		ret = mipi_dsi_dcs_write(dsi, cmd, seqp, chunk);
		if (ret < 0) {
			dev_err(dev, "error sending CMD %02x chunk\n", cmd);
			return ret;
		}
		cmdwritten += chunk;
		seqp += chunk;
	}
	dev_dbg(dev, "sent command %02x %02x bytes\n", cmd, cmdwritten);

	usleep_range(8000, 9000);

	return 0;
}

static int s6e63m0_dsi_probe(struct mipi_dsi_device *dsi)
{
	struct device *dev = &dsi->dev;
	int ret;

	dsi->lanes = 2;
	dsi->format = MIPI_DSI_FMT_RGB888;
	dsi->hs_rate = 349440000;
	dsi->lp_rate = 9600000;
	dsi->mode_flags = MIPI_DSI_MODE_VIDEO |
		MIPI_DSI_MODE_VIDEO_BURST;

	ret = s6e63m0_probe(dev, NULL, s6e63m0_dsi_dcs_read,
			    s6e63m0_dsi_dcs_write, true);
	if (ret)
		return ret;

	ret = mipi_dsi_attach(dsi);
	if (ret < 0)
		s6e63m0_remove(dev);

	return ret;
}

static void s6e63m0_dsi_remove(struct mipi_dsi_device *dsi)
{
	mipi_dsi_detach(dsi);
	s6e63m0_remove(&dsi->dev);
}

static const struct of_device_id s6e63m0_dsi_of_match[] = {
	{ .compatible = "samsung,s6e63m0" },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, s6e63m0_dsi_of_match);

static struct mipi_dsi_driver s6e63m0_dsi_driver = {
	.probe			= s6e63m0_dsi_probe,
	.remove			= s6e63m0_dsi_remove,
	.driver			= {
		.name		= "panel-samsung-s6e63m0",
		.of_match_table = s6e63m0_dsi_of_match,
	},
};
module_mipi_dsi_driver(s6e63m0_dsi_driver);

MODULE_AUTHOR("Linus Walleij <linusw@kernel.org>");
MODULE_DESCRIPTION("s6e63m0 LCD DSI Driver");
MODULE_LICENSE("GPL v2");