video: clps711x: Add new Cirrus Logic CLPS711X framebuffer driver

This adds support for the framebuffer available in the Cirrus
Logic CLPS711X CPUs.
FB features:
- 1-2-4 bits per pixel.
- Programmable panel size to a maximum of 1024x256 at 4 bps.
- Relocatible Frame Buffer (SRAM or SDRAM).
- Programmable refresh rates.
- 16 gray scale values.
This new driver is designed to usage with devicetree only.
The driver have been tested with custom board equipped
Cirrus Logic EP7312.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

3 files changed, 415 insertions, 6 deletions

diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
index 59c98bfd5a8a..06e1ff8f9b62 100644
--- a/drivers/video/fbdev/Kconfig
+++ b/drivers/video/fbdev/Kconfig
@@ -301,15 +301,26 @@ config FB_ACORN
           hardware found in Acorn RISC PCs and other ARM-based machines.  If
           unsure, say N.
 
-config FB_CLPS711X
-        bool "CLPS711X LCD support"
-        depends on (FB = y) && ARM && ARCH_CLPS711X
+config FB_CLPS711X_OLD
+        bool
         select FB_CFB_FILLRECT
         select FB_CFB_COPYAREA
         select FB_CFB_IMAGEBLIT
+
+config FB_CLPS711X
+        tristate "CLPS711X LCD support"
+        depends on FB && (ARCH_CLPS711X || COMPILE_TEST)
+        select FB_CLPS711X_OLD if ARCH_CLPS711X && !ARCH_MULTIPLATFORM
+        select BACKLIGHT_LCD_SUPPORT
+        select FB_MODE_HELPERS
+        select FB_SYS_FILLRECT
+        select FB_SYS_COPYAREA
+        select FB_SYS_IMAGEBLIT
+        select LCD_CLASS_DEVICE
+        select VIDEOMODE_HELPERS
         help
-          Say Y to enable the Framebuffer driver for the CLPS7111 and
-          EP7212 processors.
+          Say Y to enable the Framebuffer driver for the Cirrus Logic
+          CLPS711X CPUs.
 
 config FB_SA1100
         bool "SA-1100 LCD support"
diff --git a/drivers/video/fbdev/Makefile b/drivers/video/fbdev/Makefile
index 0284f2a12538..4e0b8c40ffe6 100644
--- a/drivers/video/fbdev/Makefile
+++ b/drivers/video/fbdev/Makefile
@@ -14,7 +14,8 @@ obj-$(CONFIG_FB_WMT_GE_ROPS)   += wmt_ge_rops.o
 # Hardware specific drivers go first
 obj-$(CONFIG_FB_AMIGA)            += amifb.o c2p_planar.o
 obj-$(CONFIG_FB_ARC)              += arcfb.o
-obj-$(CONFIG_FB_CLPS711X)         += clps711xfb.o
+obj-$(CONFIG_FB_CLPS711X)         += clps711x-fb.o
+obj-$(CONFIG_FB_CLPS711X_OLD)     += clps711xfb.o
 obj-$(CONFIG_FB_CYBER2000)        += cyber2000fb.o
 obj-$(CONFIG_FB_GRVGA)            += grvga.o
 obj-$(CONFIG_FB_PM2)              += pm2fb.o
diff --git a/drivers/video/fbdev/clps711x-fb.c b/drivers/video/fbdev/clps711x-fb.c
new file mode 100644
index 000000000000..4d17fbb3ffab
--- /dev/null
+++ b/drivers/video/fbdev/clps711x-fb.c
@@ -0,0 +1,397 @@
+/*
+ * Cirrus Logic CLPS711X FB driver
+ *
+ * Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
+ * Based on driver by Russell King <rmk@arm.linux.org.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/fb.h>
+#include <linux/io.h>
+#include <linux/lcd.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/clps711x.h>
+#include <linux/regulator/consumer.h>
+#include <video/of_display_timing.h>
+
+#define CLPS711X_FB_NAME        "clps711x-fb"
+#define CLPS711X_FB_BPP_MAX     (4)
+
+/* Registers relative to LCDCON */
+#define CLPS711X_LCDCON         (0x0000)
+# define LCDCON_GSEN            BIT(30)
+# define LCDCON_GSMD            BIT(31)
+#define CLPS711X_PALLSW         (0x0280)
+#define CLPS711X_PALMSW         (0x02c0)
+#define CLPS711X_FBADDR         (0x0d40)
+
+struct clps711x_fb_info {
+        struct clk              *clk;
+        void __iomem            *base;
+        struct regmap           *syscon;
+        resource_size_t         buffsize;
+        struct fb_videomode     mode;
+        struct regulator        *lcd_pwr;
+        u32                     ac_prescale;
+        bool                    cmap_invert;
+};
+
+static int clps711x_fb_setcolreg(u_int regno, u_int red, u_int green,
+                                 u_int blue, u_int transp, struct fb_info *info)
+{
+        struct clps711x_fb_info *cfb = info->par;
+        u32 level, mask, shift;
+
+        if (regno >= BIT(info->var.bits_per_pixel))
+                return -EINVAL;
+
+        shift = 4 * (regno & 7);
+        mask  = 0xf << shift;
+        /* gray = 0.30*R + 0.58*G + 0.11*B */
+        level = (((red * 77 + green * 151 + blue * 28) >> 20) << shift) & mask;
+        if (cfb->cmap_invert)
+                level = 0xf - level;
+
+        regno = (regno < 8) ? CLPS711X_PALLSW : CLPS711X_PALMSW;
+
+        writel((readl(cfb->base + regno) & ~mask) | level, cfb->base + regno);
+
+        return 0;
+}
+
+static int clps711x_fb_check_var(struct fb_var_screeninfo *var,
+                                 struct fb_info *info)
+{
+        u32 val;
+
+        if (var->bits_per_pixel < 1 ||
+            var->bits_per_pixel > CLPS711X_FB_BPP_MAX)
+                return -EINVAL;
+
+        if (!var->pixclock)
+                return -EINVAL;
+
+        val = DIV_ROUND_UP(var->xres, 16) - 1;
+        if (val < 0x01 || val > 0x3f)
+                return -EINVAL;
+
+        val = DIV_ROUND_UP(var->yres * var->xres * var->bits_per_pixel, 128);
+        val--;
+        if (val < 0x001 || val > 0x1fff)
+                return -EINVAL;
+
+        var->transp.msb_right   = 0;
+        var->transp.offset      = 0;
+        var->transp.length      = 0;
+        var->red.msb_right      = 0;
+        var->red.offset         = 0;
+        var->red.length         = var->bits_per_pixel;
+        var->green              = var->red;
+        var->blue               = var->red;
+        var->grayscale          = var->bits_per_pixel > 1;
+
+        return 0;
+}
+
+static int clps711x_fb_set_par(struct fb_info *info)
+{
+        struct clps711x_fb_info *cfb = info->par;
+        resource_size_t size;
+        u32 lcdcon, pps;
+
+        size = (info->var.xres * info->var.yres * info->var.bits_per_pixel) / 8;
+        if (size > cfb->buffsize)
+                return -EINVAL;
+
+        switch (info->var.bits_per_pixel) {
+        case 1:
+                info->fix.visual = FB_VISUAL_MONO01;
+                break;
+        case 2:
+        case 4:
+                info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        info->fix.line_length = info->var.xres * info->var.bits_per_pixel / 8;
+        info->fix.smem_len = size;
+
+        lcdcon = (info->var.xres * info->var.yres *
+                  info->var.bits_per_pixel) / 128 - 1;
+        lcdcon |= ((info->var.xres / 16) - 1) << 13;
+        lcdcon |= (cfb->ac_prescale & 0x1f) << 25;
+
+        pps = clk_get_rate(cfb->clk) / (PICOS2KHZ(info->var.pixclock) * 1000);
+        if (pps)
+                pps--;
+        lcdcon |= (pps & 0x3f) << 19;
+
+        if (info->var.bits_per_pixel == 4)
+                lcdcon |= LCDCON_GSMD;
+        if (info->var.bits_per_pixel >= 2)
+                lcdcon |= LCDCON_GSEN;
+
+        /* LCDCON must only be changed while the LCD is disabled */
+        regmap_update_bits(cfb->syscon, SYSCON_OFFSET, SYSCON1_LCDEN, 0);
+        writel(lcdcon, cfb->base + CLPS711X_LCDCON);
+        regmap_update_bits(cfb->syscon, SYSCON_OFFSET,
+                           SYSCON1_LCDEN, SYSCON1_LCDEN);
+
+        return 0;
+}
+
+static int clps711x_fb_blank(int blank, struct fb_info *info)
+{
+        /* Return happy */
+        return 0;
+}
+
+static struct fb_ops clps711x_fb_ops = {
+        .owner          = THIS_MODULE,
+        .fb_setcolreg   = clps711x_fb_setcolreg,
+        .fb_check_var   = clps711x_fb_check_var,
+        .fb_set_par     = clps711x_fb_set_par,
+        .fb_blank       = clps711x_fb_blank,
+        .fb_fillrect    = sys_fillrect,
+        .fb_copyarea    = sys_copyarea,
+        .fb_imageblit   = sys_imageblit,
+};
+
+static int clps711x_lcd_check_fb(struct lcd_device *lcddev, struct fb_info *fi)
+{
+        struct clps711x_fb_info *cfb = dev_get_drvdata(&lcddev->dev);
+
+        return (!fi || fi->par == cfb) ? 1 : 0;
+}
+
+static int clps711x_lcd_get_power(struct lcd_device *lcddev)
+{
+        struct clps711x_fb_info *cfb = dev_get_drvdata(&lcddev->dev);
+
+        if (!IS_ERR_OR_NULL(cfb->lcd_pwr))
+                if (!regulator_is_enabled(cfb->lcd_pwr))
+                        return FB_BLANK_NORMAL;
+
+        return FB_BLANK_UNBLANK;
+}
+
+static int clps711x_lcd_set_power(struct lcd_device *lcddev, int blank)
+{
+        struct clps711x_fb_info *cfb = dev_get_drvdata(&lcddev->dev);
+
+        if (!IS_ERR_OR_NULL(cfb->lcd_pwr)) {
+                if (blank == FB_BLANK_UNBLANK) {
+                        if (!regulator_is_enabled(cfb->lcd_pwr))
+                                return regulator_enable(cfb->lcd_pwr);
+                } else {
+                        if (regulator_is_enabled(cfb->lcd_pwr))
+                                return regulator_disable(cfb->lcd_pwr);
+                }
+        }
+
+        return 0;
+}
+
+static struct lcd_ops clps711x_lcd_ops = {
+        .check_fb       = clps711x_lcd_check_fb,
+        .get_power      = clps711x_lcd_get_power,
+        .set_power      = clps711x_lcd_set_power,
+};
+
+static int clps711x_fb_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        struct device_node *disp, *np = dev->of_node;
+        struct clps711x_fb_info *cfb;
+        struct lcd_device *lcd;
+        struct fb_info *info;
+        struct resource *res;
+        int ret = -ENOENT;
+        u32 val;
+
+        if (fb_get_options(CLPS711X_FB_NAME, NULL))
+                return -ENODEV;
+
+        info = framebuffer_alloc(sizeof(*cfb), dev);
+        if (!info)
+                return -ENOMEM;
+
+        cfb = info->par;
+        platform_set_drvdata(pdev, info);
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!res)
+                goto out_fb_release;
+        cfb->base = devm_ioremap(dev, res->start, resource_size(res));
+        if (!cfb->base) {
+                ret = -ENOMEM;
+                goto out_fb_release;
+        }
+
+        info->fix.mmio_start = res->start;
+        info->fix.mmio_len = resource_size(res);
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+        info->screen_base = devm_ioremap_resource(dev, res);
+        if (IS_ERR(info->screen_base)) {
+                ret = PTR_ERR(info->screen_base);
+                goto out_fb_release;
+        }
+
+        /* Physical address should be aligned to 256 MiB */
+        if (res->start & 0x0fffffff) {
+                ret = -EINVAL;
+                goto out_fb_release;
+        }
+
+        info->apertures = alloc_apertures(1);
+        if (!info->apertures) {
+                ret = -ENOMEM;
+                goto out_fb_release;
+        }
+
+        cfb->buffsize = resource_size(res);
+        info->fix.smem_start = res->start;
+        info->apertures->ranges[0].base = info->fix.smem_start;
+        info->apertures->ranges[0].size = cfb->buffsize;
+
+        cfb->clk = devm_clk_get(dev, NULL);
+        if (IS_ERR(cfb->clk)) {
+                ret = PTR_ERR(cfb->clk);
+                goto out_fb_release;
+        }
+
+        cfb->syscon =
+                syscon_regmap_lookup_by_compatible("cirrus,clps711x-syscon1");
+        if (IS_ERR(cfb->syscon)) {
+                ret = PTR_ERR(cfb->syscon);
+                goto out_fb_release;
+        }
+
+        disp = of_parse_phandle(np, "display", 0);
+        if (!disp) {
+                dev_err(&pdev->dev, "No display defined\n");
+                ret = -ENODATA;
+                goto out_fb_release;
+        }
+
+        ret = of_get_fb_videomode(disp, &cfb->mode, OF_USE_NATIVE_MODE);
+        if (ret)
+                goto out_fb_release;
+
+        of_property_read_u32(disp, "ac-prescale", &cfb->ac_prescale);
+        cfb->cmap_invert = of_property_read_bool(disp, "cmap-invert");
+
+        ret = of_property_read_u32(disp, "bits-per-pixel",
+                                   &info->var.bits_per_pixel);
+        if (ret)
+                goto out_fb_release;
+
+        /* Force disable LCD on any mismatch */
+        if (info->fix.smem_start != (readb(cfb->base + CLPS711X_FBADDR) << 28))
+                regmap_update_bits(cfb->syscon, SYSCON_OFFSET,
+                                   SYSCON1_LCDEN, 0);
+
+        ret = regmap_read(cfb->syscon, SYSCON_OFFSET, &val);
+        if (ret)
+                goto out_fb_release;
+
+        if (!(val & SYSCON1_LCDEN)) {
+                /* Setup start FB address */
+                writeb(info->fix.smem_start >> 28, cfb->base + CLPS711X_FBADDR);
+                /* Clean FB memory */
+                memset(info->screen_base, 0, cfb->buffsize);
+        }
+
+        cfb->lcd_pwr = devm_regulator_get(dev, "lcd");
+        if (PTR_ERR(cfb->lcd_pwr) == -EPROBE_DEFER) {
+                ret = -EPROBE_DEFER;
+                goto out_fb_release;
+        }
+
+        info->fbops = &clps711x_fb_ops;
+        info->flags = FBINFO_DEFAULT;
+        info->var.activate = FB_ACTIVATE_FORCE | FB_ACTIVATE_NOW;
+        info->var.height = -1;
+        info->var.width = -1;
+        info->var.vmode = FB_VMODE_NONINTERLACED;
+        info->fix.type = FB_TYPE_PACKED_PIXELS;
+        info->fix.accel = FB_ACCEL_NONE;
+        strlcpy(info->fix.id, CLPS711X_FB_NAME, sizeof(info->fix.id));
+        fb_videomode_to_var(&info->var, &cfb->mode);
+
+        ret = fb_alloc_cmap(&info->cmap, BIT(CLPS711X_FB_BPP_MAX), 0);
+        if (ret)
+                goto out_fb_release;
+
+        ret = fb_set_var(info, &info->var);
+        if (ret)
+                goto out_fb_dealloc_cmap;
+
+        ret = register_framebuffer(info);
+        if (ret)
+                goto out_fb_dealloc_cmap;
+
+        lcd = devm_lcd_device_register(dev, "clps711x-lcd", dev, cfb,
+                                       &clps711x_lcd_ops);
+        if (!IS_ERR(lcd))
+                return 0;
+        
+        ret = PTR_ERR(lcd);
+        unregister_framebuffer(info);
+
+out_fb_dealloc_cmap:
+        regmap_update_bits(cfb->syscon, SYSCON_OFFSET, SYSCON1_LCDEN, 0);
+        fb_dealloc_cmap(&info->cmap);
+
+out_fb_release:
+        framebuffer_release(info);
+
+        return ret;
+}
+
+static int clps711x_fb_remove(struct platform_device *pdev)
+{
+        struct fb_info *info = platform_get_drvdata(pdev);
+        struct clps711x_fb_info *cfb = info->par;
+
+        regmap_update_bits(cfb->syscon, SYSCON_OFFSET, SYSCON1_LCDEN, 0);
+
+        unregister_framebuffer(info);
+        fb_dealloc_cmap(&info->cmap);
+        framebuffer_release(info);
+
+        return 0;
+}
+
+static const struct of_device_id clps711x_fb_dt_ids[] = {
+        { .compatible = "cirrus,clps711x-fb", },
+        { }
+};
+MODULE_DEVICE_TABLE(of, clps711x_fb_dt_ids);
+
+static struct platform_driver clps711x_fb_driver = {
+        .driver = {
+                .name           = CLPS711X_FB_NAME,
+                .owner          = THIS_MODULE,
+                .of_match_table = clps711x_fb_dt_ids,
+        },
+        .probe  = clps711x_fb_probe,
+        .remove = clps711x_fb_remove,
+};
+module_platform_driver(clps711x_fb_driver);
+
+MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
+MODULE_DESCRIPTION("Cirrus Logic CLPS711X FB driver");
+MODULE_LICENSE("GPL");