sh-mobile: add support for displays, connected over the MIPI bus

Some SH-mobile SoCs have a MIPI DSI controller, that can be used to connect
MIPI displays to LCDC. This patch adds a platform driver for SH-mobile MIPI DSI
unit. It uses existing hooks in the sh_mobile_lcdcfb.c driver for display
activation and deactivation.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Tested-by: Damian Hobson-Garcia <dhobsong@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

1 files changed, 505 insertions, 0 deletions

diff --git a/drivers/video/sh_mipi_dsi.c b/drivers/video/sh_mipi_dsi.c
new file mode 100644
index 000000000000..017ae9f47d36
--- /dev/null
+++ b/drivers/video/sh_mipi_dsi.c
@@ -0,0 +1,505 @@
+/*
+ * Renesas SH-mobile MIPI DSI support
+ *
+ * Copyright (C) 2010 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ *
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include <video/mipi_display.h>
+#include <video/sh_mipi_dsi.h>
+#include <video/sh_mobile_lcdc.h>
+
+#define CMTSRTCTR	0x80d0
+#define CMTSRTREQ	0x8070
+
+#define DSIINTE		0x0060
+
+/* E.g., sh7372 has 2 MIPI-DSIs - one for each LCDC */
+#define MAX_SH_MIPI_DSI 2
+
+struct sh_mipi {
+	void __iomem	*base;
+	struct clk	*dsit_clk;
+	struct clk	*dsip_clk;
+};
+
+static struct sh_mipi *mipi_dsi[MAX_SH_MIPI_DSI];
+
+/* Protect the above array */
+static DEFINE_MUTEX(array_lock);
+
+static struct sh_mipi *sh_mipi_by_handle(int handle)
+{
+	if (handle >= ARRAY_SIZE(mipi_dsi) || handle < 0)
+		return NULL;
+
+	return mipi_dsi[handle];
+}
+
+static int sh_mipi_send_short(struct sh_mipi *mipi, u8 dsi_cmd,
+			      u8 cmd, u8 param)
+{
+	u32 data = (dsi_cmd << 24) | (cmd << 16) | (param << 8);
+	int cnt = 100;
+
+	/* transmit a short packet to LCD panel */
+	iowrite32(1 | data, mipi->base + 0x80d0); /* CMTSRTCTR */
+	iowrite32(1, mipi->base + 0x8070); /* CMTSRTREQ */
+
+	while ((ioread32(mipi->base + 0x8070) & 1) && --cnt)
+		udelay(1);
+
+	return cnt ? 0 : -ETIMEDOUT;
+}
+
+#define LCD_CHAN2MIPI(c) ((c) < LCDC_CHAN_MAINLCD || (c) > LCDC_CHAN_SUBLCD ? \
+				-EINVAL : (c) - 1)
+
+static int sh_mipi_dcs(int handle, u8 cmd)
+{
+	struct sh_mipi *mipi = sh_mipi_by_handle(LCD_CHAN2MIPI(handle));
+	if (!mipi)
+		return -ENODEV;
+	return sh_mipi_send_short(mipi, MIPI_DSI_DCS_SHORT_WRITE, cmd, 0);
+}
+
+static int sh_mipi_dcs_param(int handle, u8 cmd, u8 param)
+{
+	struct sh_mipi *mipi = sh_mipi_by_handle(LCD_CHAN2MIPI(handle));
+	if (!mipi)
+		return -ENODEV;
+	return sh_mipi_send_short(mipi, MIPI_DSI_DCS_SHORT_WRITE_PARAM, cmd,
+				  param);
+}
+
+static void sh_mipi_dsi_enable(struct sh_mipi *mipi, bool enable)
+{
+	/*
+	 * enable LCDC data tx, transition to LPS after completion of each HS
+	 * packet
+	 */
+	iowrite32(0x00000002 | enable, mipi->base + 0x8000); /* DTCTR */
+}
+
+static void sh_mipi_shutdown(struct platform_device *pdev)
+{
+	struct sh_mipi *mipi = platform_get_drvdata(pdev);
+
+	sh_mipi_dsi_enable(mipi, false);
+}
+
+static void mipi_display_on(void *arg)
+{
+	struct sh_mipi *mipi = arg;
+
+	sh_mipi_dsi_enable(mipi, true);
+}
+
+static void mipi_display_off(void *arg)
+{
+	struct sh_mipi *mipi = arg;
+
+	sh_mipi_dsi_enable(mipi, false);
+}
+
+static int __init sh_mipi_setup(struct sh_mipi *mipi,
+				struct sh_mipi_dsi_info *pdata)
+{
+	void __iomem *base = mipi->base;
+	struct sh_mobile_lcdc_chan_cfg *ch = pdata->lcd_chan;
+	u32 pctype, datatype, pixfmt;
+	u32 linelength;
+	bool yuv;
+
+	/* Select data format */
+	switch (pdata->data_format) {
+	case MIPI_RGB888:
+		pctype = 0;
+		datatype = MIPI_DSI_PACKED_PIXEL_STREAM_24;
+		pixfmt = MIPI_DCS_PIXEL_FMT_24BIT;
+		linelength = ch->lcd_cfg.xres * 3;
+		yuv = false;
+		break;
+	case MIPI_RGB565:
+		pctype = 1;
+		datatype = MIPI_DSI_PACKED_PIXEL_STREAM_16;
+		pixfmt = MIPI_DCS_PIXEL_FMT_16BIT;
+		linelength = ch->lcd_cfg.xres * 2;
+		yuv = false;
+		break;
+	case MIPI_RGB666_LP:
+		pctype = 2;
+		datatype = MIPI_DSI_PIXEL_STREAM_3BYTE_18;
+		pixfmt = MIPI_DCS_PIXEL_FMT_24BIT;
+		linelength = ch->lcd_cfg.xres * 3;
+		yuv = false;
+		break;
+	case MIPI_RGB666:
+		pctype = 3;
+		datatype = MIPI_DSI_PACKED_PIXEL_STREAM_18;
+		pixfmt = MIPI_DCS_PIXEL_FMT_18BIT;
+		linelength = (ch->lcd_cfg.xres * 18 + 7) / 8;
+		yuv = false;
+		break;
+	case MIPI_BGR888:
+		pctype = 8;
+		datatype = MIPI_DSI_PACKED_PIXEL_STREAM_24;
+		pixfmt = MIPI_DCS_PIXEL_FMT_24BIT;
+		linelength = ch->lcd_cfg.xres * 3;
+		yuv = false;
+		break;
+	case MIPI_BGR565:
+		pctype = 9;
+		datatype = MIPI_DSI_PACKED_PIXEL_STREAM_16;
+		pixfmt = MIPI_DCS_PIXEL_FMT_16BIT;
+		linelength = ch->lcd_cfg.xres * 2;
+		yuv = false;
+		break;
+	case MIPI_BGR666_LP:
+		pctype = 0xa;
+		datatype = MIPI_DSI_PIXEL_STREAM_3BYTE_18;
+		pixfmt = MIPI_DCS_PIXEL_FMT_24BIT;
+		linelength = ch->lcd_cfg.xres * 3;
+		yuv = false;
+		break;
+	case MIPI_BGR666:
+		pctype = 0xb;
+		datatype = MIPI_DSI_PACKED_PIXEL_STREAM_18;
+		pixfmt = MIPI_DCS_PIXEL_FMT_18BIT;
+		linelength = (ch->lcd_cfg.xres * 18 + 7) / 8;
+		yuv = false;
+		break;
+	case MIPI_YUYV:
+		pctype = 4;
+		datatype = MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR16;
+		pixfmt = MIPI_DCS_PIXEL_FMT_16BIT;
+		linelength = ch->lcd_cfg.xres * 2;
+		yuv = true;
+		break;
+	case MIPI_UYVY:
+		pctype = 5;
+		datatype = MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR16;
+		pixfmt = MIPI_DCS_PIXEL_FMT_16BIT;
+		linelength = ch->lcd_cfg.xres * 2;
+		yuv = true;
+		break;
+	case MIPI_YUV420_L:
+		pctype = 6;
+		datatype = MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR12;
+		pixfmt = MIPI_DCS_PIXEL_FMT_12BIT;
+		linelength = (ch->lcd_cfg.xres * 12 + 7) / 8;
+		yuv = true;
+		break;
+	case MIPI_YUV420:
+		pctype = 7;
+		datatype = MIPI_DSI_PACKED_PIXEL_STREAM_YCBCR12;
+		pixfmt = MIPI_DCS_PIXEL_FMT_12BIT;
+		/* Length of U/V line */
+		linelength = (ch->lcd_cfg.xres + 1) / 2;
+		yuv = true;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if ((yuv && ch->interface_type != YUV422) ||
+	    (!yuv && ch->interface_type != RGB24))
+		return -EINVAL;
+
+	/* reset DSI link */
+	iowrite32(0x00000001, base); /* SYSCTRL */
+	/* Hold reset for 100 cycles of the slowest of bus, HS byte and LP clock */
+	udelay(50);
+	iowrite32(0x00000000, base); /* SYSCTRL */
+
+	/* setup DSI link */
+
+	/*
+	 * Default = ULPS enable |
+	 *	Contention detection enabled |
+	 *	EoT packet transmission enable |
+	 *	CRC check enable |
+	 *	ECC check enable
+	 * additionally enable first two lanes
+	 */
+	iowrite32(0x00003703, base + 0x04); /* SYSCONF */
+	/*
+	 * T_wakeup = 0x7000
+	 * T_hs-trail = 3
+	 * T_hs-prepare = 3
+	 * T_clk-trail = 3
+	 * T_clk-prepare = 2
+	 */
+	iowrite32(0x70003332, base + 0x08); /* TIMSET */
+	/* no responses requested */
+	iowrite32(0x00000000, base + 0x18); /* RESREQSET0 */
+	/* request response to packets of type 0x28 */
+	iowrite32(0x00000100, base + 0x1c); /* RESREQSET1 */
+	/* High-speed transmission timeout, default 0xffffffff */
+	iowrite32(0x0fffffff, base + 0x20); /* HSTTOVSET */
+	/* LP reception timeout, default 0xffffffff */
+	iowrite32(0x0fffffff, base + 0x24); /* LPRTOVSET */
+	/* Turn-around timeout, default 0xffffffff */
+	iowrite32(0x0fffffff, base + 0x28); /* TATOVSET */
+	/* Peripheral reset timeout, default 0xffffffff */
+	iowrite32(0x0fffffff, base + 0x2c); /* PRTOVSET */
+	/* Enable timeout counters */
+	iowrite32(0x00000f00, base + 0x30); /* DSICTRL */
+	/* Interrupts not used, disable all */
+	iowrite32(0, base + DSIINTE);
+	/* DSI-Tx bias on */
+	iowrite32(0x00000001, base + 0x70); /* PHYCTRL */
+	udelay(200);
+	/* Deassert resets, power on, set multiplier */
+	iowrite32(0x03070b01, base + 0x70); /* PHYCTRL */
+
+	/* setup l-bridge */
+
+	/*
+	 * Enable transmission of all packets,
+	 * transmit LPS after each HS packet completion
+	 */
+	iowrite32(0x00000006, base + 0x8000); /* DTCTR */
+	/* VSYNC width = 2 (<< 17) */
+	iowrite32(0x00040000 | (pctype << 12) | datatype, base + 0x8020); /* VMCTR1 */
+	/*
+	 * Non-burst mode with sync pulses: VSE and HSE are output,
+	 * HSA period allowed, no commands in LP
+	 */
+	iowrite32(0x00e00000, base + 0x8024); /* VMCTR2 */
+	/*
+	 * 0x660 = 1632 bytes per line (RGB24, 544 pixels: see
+	 * sh_mobile_lcdc_info.ch[0].lcd_cfg.xres), HSALEN = 1 - default
+	 * (unused, since VMCTR2[HSABM] = 0)
+	 */
+	iowrite32(1 | (linelength << 16), base + 0x8028); /* VMLEN1 */
+
+	msleep(5);
+
+	/* setup LCD panel */
+
+	/* cf. drivers/video/omap/lcd_mipid.c */
+	sh_mipi_dcs(ch->chan, MIPI_DCS_EXIT_SLEEP_MODE);
+	msleep(120);
+	/*
+	 * [7] - Page Address Mode
+	 * [6] - Column Address Mode
+	 * [5] - Page / Column Address Mode
+	 * [4] - Display Device Line Refresh Order
+	 * [3] - RGB/BGR Order
+	 * [2] - Display Data Latch Data Order
+	 * [1] - Flip Horizontal
+	 * [0] - Flip Vertical
+	 */
+	sh_mipi_dcs_param(ch->chan, MIPI_DCS_SET_ADDRESS_MODE, 0x00);
+	/* cf. set_data_lines() */
+	sh_mipi_dcs_param(ch->chan, MIPI_DCS_SET_PIXEL_FORMAT,
+			  pixfmt << 4);
+	sh_mipi_dcs(ch->chan, MIPI_DCS_SET_DISPLAY_ON);
+
+	return 0;
+}
+
+static int __init sh_mipi_probe(struct platform_device *pdev)
+{
+	struct sh_mipi *mipi;
+	struct sh_mipi_dsi_info *pdata = pdev->dev.platform_data;
+	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	unsigned long rate, f_current;
+	int idx = pdev->id, ret;
+	char dsip_clk[] = "dsi.p_clk";
+
+	if (!res || idx >= ARRAY_SIZE(mipi_dsi) || !pdata)
+		return -ENODEV;
+
+	mutex_lock(&array_lock);
+	if (idx < 0)
+		for (idx = 0; idx < ARRAY_SIZE(mipi_dsi) && mipi_dsi[idx]; idx++)
+			;
+
+	if (idx == ARRAY_SIZE(mipi_dsi)) {
+		ret = -EBUSY;
+		goto efindslot;
+	}
+
+	mipi = kzalloc(sizeof(*mipi), GFP_KERNEL);
+	if (!mipi) {
+		ret = -ENOMEM;
+		goto ealloc;
+	}
+
+	if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
+		dev_err(&pdev->dev, "MIPI register region already claimed\n");
+		ret = -EBUSY;
+		goto ereqreg;
+	}
+
+	mipi->base = ioremap(res->start, resource_size(res));
+	if (!mipi->base) {
+		ret = -ENOMEM;
+		goto emap;
+	}
+
+	mipi->dsit_clk = clk_get(&pdev->dev, "dsit_clk");
+	if (IS_ERR(mipi->dsit_clk)) {
+		ret = PTR_ERR(mipi->dsit_clk);
+		goto eclktget;
+	}
+
+	f_current = clk_get_rate(mipi->dsit_clk);
+	/* 80MHz required by the datasheet */
+	rate = clk_round_rate(mipi->dsit_clk, 80000000);
+	if (rate > 0 && rate != f_current)
+		ret = clk_set_rate(mipi->dsit_clk, rate);
+	else
+		ret = rate;
+	if (ret < 0)
+		goto esettrate;
+
+	dev_dbg(&pdev->dev, "DSI-T clk %lu -> %lu\n", f_current, rate);
+
+	sprintf(dsip_clk, "dsi%1.1dp_clk", idx);
+	mipi->dsip_clk = clk_get(&pdev->dev, dsip_clk);
+	if (IS_ERR(mipi->dsip_clk)) {
+		ret = PTR_ERR(mipi->dsip_clk);
+		goto eclkpget;
+	}
+
+	f_current = clk_get_rate(mipi->dsip_clk);
+	/* Between 10 and 50MHz */
+	rate = clk_round_rate(mipi->dsip_clk, 24000000);
+	if (rate > 0 && rate != f_current)
+		ret = clk_set_rate(mipi->dsip_clk, rate);
+	else
+		ret = rate;
+	if (ret < 0)
+		goto esetprate;
+
+	dev_dbg(&pdev->dev, "DSI-P clk %lu -> %lu\n", f_current, rate);
+
+	msleep(10);
+
+	ret = clk_enable(mipi->dsit_clk);
+	if (ret < 0)
+		goto eclkton;
+
+	ret = clk_enable(mipi->dsip_clk);
+	if (ret < 0)
+		goto eclkpon;
+
+	mipi_dsi[idx] = mipi;
+
+	ret = sh_mipi_setup(mipi, pdata);
+	if (ret < 0)
+		goto emipisetup;
+
+	mutex_unlock(&array_lock);
+	platform_set_drvdata(pdev, mipi);
+
+	/* Set up LCDC callbacks */
+	pdata->lcd_chan->board_cfg.board_data = mipi;
+	pdata->lcd_chan->board_cfg.display_on = mipi_display_on;
+	pdata->lcd_chan->board_cfg.display_off = mipi_display_off;
+
+	return 0;
+
+emipisetup:
+	mipi_dsi[idx] = NULL;
+	clk_disable(mipi->dsip_clk);
+eclkpon:
+	clk_disable(mipi->dsit_clk);
+eclkton:
+esetprate:
+	clk_put(mipi->dsip_clk);
+eclkpget:
+esettrate:
+	clk_put(mipi->dsit_clk);
+eclktget:
+	iounmap(mipi->base);
+emap:
+	release_mem_region(res->start, resource_size(res));
+ereqreg:
+	kfree(mipi);
+ealloc:
+efindslot:
+	mutex_unlock(&array_lock);
+
+	return ret;
+}
+
+static int __exit sh_mipi_remove(struct platform_device *pdev)
+{
+	struct sh_mipi_dsi_info *pdata = pdev->dev.platform_data;
+	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	struct sh_mipi *mipi = platform_get_drvdata(pdev);
+	int i, ret;
+
+	mutex_lock(&array_lock);
+
+	for (i = 0; i < ARRAY_SIZE(mipi_dsi) && mipi_dsi[i] != mipi; i++)
+		;
+
+	if (i == ARRAY_SIZE(mipi_dsi)) {
+		ret = -EINVAL;
+	} else {
+		ret = 0;
+		mipi_dsi[i] = NULL;
+	}
+
+	mutex_unlock(&array_lock);
+
+	if (ret < 0)
+		return ret;
+
+	pdata->lcd_chan->board_cfg.display_on = NULL;
+	pdata->lcd_chan->board_cfg.display_off = NULL;
+	pdata->lcd_chan->board_cfg.board_data = NULL;
+
+	clk_disable(mipi->dsip_clk);
+	clk_disable(mipi->dsit_clk);
+	clk_put(mipi->dsit_clk);
+	clk_put(mipi->dsip_clk);
+	iounmap(mipi->base);
+	if (res)
+		release_mem_region(res->start, resource_size(res));
+	platform_set_drvdata(pdev, NULL);
+	kfree(mipi);
+
+	return 0;
+}
+
+static struct platform_driver sh_mipi_driver = {
+	.remove		= __exit_p(sh_mipi_remove),
+	.shutdown	= sh_mipi_shutdown,
+	.driver = {
+		.name	= "sh-mipi-dsi",
+	},
+};
+
+static int __init sh_mipi_init(void)
+{
+	return platform_driver_probe(&sh_mipi_driver, sh_mipi_probe);
+}
+module_init(sh_mipi_init);
+
+static void __exit sh_mipi_exit(void)
+{
+	platform_driver_unregister(&sh_mipi_driver);
+}
+module_exit(sh_mipi_exit);
+
+MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
+MODULE_DESCRIPTION("SuperH / ARM-shmobile MIPI DSI driver");
+MODULE_LICENSE("GPL v2");