--- /dev/null
+/*
+ * 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");