/* * Raspberry Pi Sense HAT framebuffer driver * http://raspberrypi.org * * Copyright (C) 2015 Raspberry Pi * * Author: Serge Schneider * * 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 #include #include #include #include #include #include #include #include #include #include #include #include static bool lowlight; module_param(lowlight, bool, 0); MODULE_PARM_DESC(lowlight, "Reduce LED matrix brightness to one third"); struct rpisense_fb_param { char __iomem *vmem; u8 *vmem_work; u32 vmemsize; u8 *gamma; }; static u8 gamma_default[32] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x02, 0x02, 0x03, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0E, 0x0F, 0x11, 0x12, 0x14, 0x15, 0x17, 0x19, 0x1B, 0x1D, 0x1F,}; static u8 gamma_low[32] = {0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x02, 0x02, 0x02, 0x03, 0x03, 0x03, 0x04, 0x04, 0x05, 0x05, 0x06, 0x06, 0x07, 0x07, 0x08, 0x08, 0x09, 0x0A, 0x0A,}; static u8 gamma_user[32]; static u32 pseudo_palette[16]; static struct rpisense_fb_param rpisense_fb_param = { .vmem = NULL, .vmemsize = 128, .gamma = gamma_default, }; static struct fb_deferred_io rpisense_fb_defio; static struct fb_fix_screeninfo rpisense_fb_fix = { .id = "RPi-Sense FB", .type = FB_TYPE_PACKED_PIXELS, .visual = FB_VISUAL_TRUECOLOR, .xpanstep = 0, .ypanstep = 0, .ywrapstep = 0, .accel = FB_ACCEL_NONE, .line_length = 16, }; static struct fb_var_screeninfo rpisense_fb_var = { .xres = 8, .yres = 8, .xres_virtual = 8, .yres_virtual = 8, .bits_per_pixel = 16, .red = {11, 5, 0}, .green = {5, 6, 0}, .blue = {0, 5, 0}, }; static ssize_t rpisense_fb_write(struct fb_info *info, const char __user *buf, size_t count, loff_t *ppos) { ssize_t res = fb_sys_write(info, buf, count, ppos); schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay); return res; } static void rpisense_fb_fillrect(struct fb_info *info, const struct fb_fillrect *rect) { sys_fillrect(info, rect); schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay); } static void rpisense_fb_copyarea(struct fb_info *info, const struct fb_copyarea *area) { sys_copyarea(info, area); schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay); } static void rpisense_fb_imageblit(struct fb_info *info, const struct fb_image *image) { sys_imageblit(info, image); schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay); } static void rpisense_fb_deferred_io(struct fb_info *info, struct list_head *pagelist) { int i; int j; u8 *vmem_work = rpisense_fb_param.vmem_work; u16 *mem = (u16 *)rpisense_fb_param.vmem; u8 *gamma = rpisense_fb_param.gamma; struct rpisense_fb *rpisense_fb = info->par; for (j = 0; j < 8; j++) { for (i = 0; i < 8; i++) { vmem_work[(j * 24) + i] = gamma[(mem[(j * 8) + i] >> 11) & 0x1F]; vmem_work[(j * 24) + (i + 8)] = gamma[(mem[(j * 8) + i] >> 6) & 0x1F]; vmem_work[(j * 24) + (i + 16)] = gamma[(mem[(j * 8) + i]) & 0x1F]; } } regmap_bulk_write(rpisense_fb->regmap, 0, vmem_work, 192); } static struct fb_deferred_io rpisense_fb_defio = { .delay = HZ/100, .deferred_io = rpisense_fb_deferred_io, }; static int rpisense_fb_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg) { switch (cmd) { case SENSEFB_FBIOGET_GAMMA: if (copy_to_user((void __user *) arg, rpisense_fb_param.gamma, sizeof(u8[32]))) return -EFAULT; return 0; case SENSEFB_FBIOSET_GAMMA: if (copy_from_user(gamma_user, (void __user *)arg, sizeof(u8[32]))) return -EFAULT; rpisense_fb_param.gamma = gamma_user; schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay); return 0; case SENSEFB_FBIORESET_GAMMA: switch (arg) { case 0: rpisense_fb_param.gamma = gamma_default; break; case 1: rpisense_fb_param.gamma = gamma_low; break; case 2: rpisense_fb_param.gamma = gamma_user; break; default: return -EINVAL; } schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay); break; default: return -EINVAL; } return 0; } static struct fb_ops rpisense_fb_ops = { .owner = THIS_MODULE, .fb_read = fb_sys_read, .fb_write = rpisense_fb_write, .fb_fillrect = rpisense_fb_fillrect, .fb_copyarea = rpisense_fb_copyarea, .fb_imageblit = rpisense_fb_imageblit, .fb_ioctl = rpisense_fb_ioctl, .fb_mmap = fb_deferred_io_mmap, }; static int rpisense_fb_probe(struct platform_device *pdev) { struct fb_info *info; int ret = -ENOMEM; struct rpisense_fb *rpisense_fb; info = framebuffer_alloc(sizeof(*rpisense_fb), &pdev->dev); if (!info) { dev_err(&pdev->dev, "Could not allocate framebuffer.\n"); goto err_malloc; } rpisense_fb = info->par; platform_set_drvdata(pdev, rpisense_fb); rpisense_fb->pdev = pdev; rpisense_fb->regmap = dev_get_regmap(pdev->dev.parent, NULL); if (!rpisense_fb->regmap) { dev_err(&pdev->dev, "unable to get sensehat regmap"); return -ENODEV; } rpisense_fb_param.vmem = vzalloc(rpisense_fb_param.vmemsize); if (!rpisense_fb_param.vmem) return ret; rpisense_fb_param.vmem_work = devm_kmalloc(&pdev->dev, 193, GFP_KERNEL); if (!rpisense_fb_param.vmem_work) goto err_malloc; rpisense_fb_fix.smem_start = (unsigned long)rpisense_fb_param.vmem; rpisense_fb_fix.smem_len = rpisense_fb_param.vmemsize; info->fbops = &rpisense_fb_ops; info->fix = rpisense_fb_fix; info->var = rpisense_fb_var; info->fbdefio = &rpisense_fb_defio; info->flags = FBINFO_VIRTFB; info->screen_base = rpisense_fb_param.vmem; info->screen_size = rpisense_fb_param.vmemsize; info->pseudo_palette = pseudo_palette; if (lowlight) rpisense_fb_param.gamma = gamma_low; fb_deferred_io_init(info); ret = register_framebuffer(info); if (ret < 0) { dev_err(&pdev->dev, "Could not register framebuffer.\n"); goto err_fballoc; } fb_info(info, "%s frame buffer device\n", info->fix.id); schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay); return 0; err_fballoc: framebuffer_release(info); err_malloc: vfree(rpisense_fb_param.vmem); return ret; } static void rpisense_fb_remove(struct platform_device *pdev) { struct rpisense_fb *rpisense_fb = platform_get_drvdata(pdev); struct fb_info *info = rpisense_fb->info; if (info) { unregister_framebuffer(info); fb_deferred_io_cleanup(info); framebuffer_release(info); vfree(rpisense_fb_param.vmem); } } static const struct of_device_id rpisense_fb_id[] = { { .compatible = "raspberrypi,rpi-sense-fb" }, { }, }; MODULE_DEVICE_TABLE(of, rpisense_fb_id); static struct platform_driver rpisense_fb_driver = { .probe = rpisense_fb_probe, .remove = rpisense_fb_remove, .driver = { .name = "rpi-sense-fb", .owner = THIS_MODULE, .of_match_table = rpisense_fb_id, }, }; module_platform_driver(rpisense_fb_driver); MODULE_DESCRIPTION("Raspberry Pi Sense HAT framebuffer driver"); MODULE_AUTHOR("Serge Schneider "); MODULE_LICENSE("GPL");