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>

3 files changed, 514 insertions, 0 deletions

diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 6e16244f3ed1..773c4a68de89 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -1879,6 +1879,13 @@ config FB_W100
 
           If unsure, say N.
 
+config SH_MIPI_DSI
+        tristate
+        depends on (SUPERH || ARCH_SHMOBILE) && HAVE_CLK
+
+config SH_LCD_MIPI_DSI
+        bool
+
 config FB_SH_MOBILE_LCDC
         tristate "SuperH Mobile LCDC framebuffer support"
         depends on FB && (SUPERH || ARCH_SHMOBILE) && HAVE_CLK
@@ -1887,6 +1894,7 @@ config FB_SH_MOBILE_LCDC
         select FB_SYS_IMAGEBLIT
         select FB_SYS_FOPS
         select FB_DEFERRED_IO
+        select SH_MIPI_DSI if SH_LCD_MIPI_DSI
         ---help---
           Frame buffer driver for the on-chip SH-Mobile LCD controller.
 
diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index ddc2af2ba45b..3c3bf867ef18 100644
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -123,6 +123,7 @@ obj-$(CONFIG_FB_IBM_GXT4500)	  += gxt4500.o
 obj-$(CONFIG_FB_PS3)              += ps3fb.o
 obj-$(CONFIG_FB_SM501)            += sm501fb.o
 obj-$(CONFIG_FB_XILINX)           += xilinxfb.o
+obj-$(CONFIG_SH_MIPI_DSI)         += sh_mipi_dsi.o
 obj-$(CONFIG_FB_SH_MOBILE_LCDC)   += sh_mobile_lcdcfb.o
 obj-$(CONFIG_FB_OMAP)             += omap/
 obj-y                             += omap2/
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");