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path: root/drivers/hid/hid-picolcd_fb.c
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Diffstat (limited to 'drivers/hid/hid-picolcd_fb.c')
-rw-r--r--drivers/hid/hid-picolcd_fb.c606
1 files changed, 606 insertions, 0 deletions
diff --git a/drivers/hid/hid-picolcd_fb.c b/drivers/hid/hid-picolcd_fb.c
new file mode 100644
index 000000000..de61c08fa
--- /dev/null
+++ b/drivers/hid/hid-picolcd_fb.c
@@ -0,0 +1,606 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/***************************************************************************
+ * Copyright (C) 2010-2012 by Bruno Prémont <bonbons@linux-vserver.org> *
+ * *
+ * Based on Logitech G13 driver (v0.4) *
+ * Copyright (C) 2009 by Rick L. Vinyard, Jr. <rvinyard@cs.nmsu.edu> *
+ * *
+ ***************************************************************************/
+
+#include <linux/hid.h>
+#include <linux/vmalloc.h>
+
+#include <linux/fb.h>
+#include <linux/module.h>
+
+#include "hid-picolcd.h"
+
+/* Framebuffer
+ *
+ * The PicoLCD use a Topway LCD module of 256x64 pixel
+ * This display area is tiled over 4 controllers with 8 tiles
+ * each. Each tile has 8x64 pixel, each data byte representing
+ * a 1-bit wide vertical line of the tile.
+ *
+ * The display can be updated at a tile granularity.
+ *
+ * Chip 1 Chip 2 Chip 3 Chip 4
+ * +----------------+----------------+----------------+----------------+
+ * | Tile 1 | Tile 1 | Tile 1 | Tile 1 |
+ * +----------------+----------------+----------------+----------------+
+ * | Tile 2 | Tile 2 | Tile 2 | Tile 2 |
+ * +----------------+----------------+----------------+----------------+
+ * ...
+ * +----------------+----------------+----------------+----------------+
+ * | Tile 8 | Tile 8 | Tile 8 | Tile 8 |
+ * +----------------+----------------+----------------+----------------+
+ */
+#define PICOLCDFB_NAME "picolcdfb"
+#define PICOLCDFB_WIDTH (256)
+#define PICOLCDFB_HEIGHT (64)
+#define PICOLCDFB_SIZE (PICOLCDFB_WIDTH * PICOLCDFB_HEIGHT / 8)
+
+#define PICOLCDFB_UPDATE_RATE_LIMIT 10
+#define PICOLCDFB_UPDATE_RATE_DEFAULT 2
+
+/* Framebuffer visual structures */
+static const struct fb_fix_screeninfo picolcdfb_fix = {
+ .id = PICOLCDFB_NAME,
+ .type = FB_TYPE_PACKED_PIXELS,
+ .visual = FB_VISUAL_MONO01,
+ .xpanstep = 0,
+ .ypanstep = 0,
+ .ywrapstep = 0,
+ .line_length = PICOLCDFB_WIDTH / 8,
+ .accel = FB_ACCEL_NONE,
+};
+
+static const struct fb_var_screeninfo picolcdfb_var = {
+ .xres = PICOLCDFB_WIDTH,
+ .yres = PICOLCDFB_HEIGHT,
+ .xres_virtual = PICOLCDFB_WIDTH,
+ .yres_virtual = PICOLCDFB_HEIGHT,
+ .width = 103,
+ .height = 26,
+ .bits_per_pixel = 1,
+ .grayscale = 1,
+ .red = {
+ .offset = 0,
+ .length = 1,
+ .msb_right = 0,
+ },
+ .green = {
+ .offset = 0,
+ .length = 1,
+ .msb_right = 0,
+ },
+ .blue = {
+ .offset = 0,
+ .length = 1,
+ .msb_right = 0,
+ },
+ .transp = {
+ .offset = 0,
+ .length = 0,
+ .msb_right = 0,
+ },
+};
+
+/* Send a given tile to PicoLCD */
+static int picolcd_fb_send_tile(struct picolcd_data *data, u8 *vbitmap,
+ int chip, int tile)
+{
+ struct hid_report *report1, *report2;
+ unsigned long flags;
+ u8 *tdata;
+ int i;
+
+ report1 = picolcd_out_report(REPORT_LCD_CMD_DATA, data->hdev);
+ if (!report1 || report1->maxfield != 1)
+ return -ENODEV;
+ report2 = picolcd_out_report(REPORT_LCD_DATA, data->hdev);
+ if (!report2 || report2->maxfield != 1)
+ return -ENODEV;
+
+ spin_lock_irqsave(&data->lock, flags);
+ if ((data->status & PICOLCD_FAILED)) {
+ spin_unlock_irqrestore(&data->lock, flags);
+ return -ENODEV;
+ }
+ hid_set_field(report1->field[0], 0, chip << 2);
+ hid_set_field(report1->field[0], 1, 0x02);
+ hid_set_field(report1->field[0], 2, 0x00);
+ hid_set_field(report1->field[0], 3, 0x00);
+ hid_set_field(report1->field[0], 4, 0xb8 | tile);
+ hid_set_field(report1->field[0], 5, 0x00);
+ hid_set_field(report1->field[0], 6, 0x00);
+ hid_set_field(report1->field[0], 7, 0x40);
+ hid_set_field(report1->field[0], 8, 0x00);
+ hid_set_field(report1->field[0], 9, 0x00);
+ hid_set_field(report1->field[0], 10, 32);
+
+ hid_set_field(report2->field[0], 0, (chip << 2) | 0x01);
+ hid_set_field(report2->field[0], 1, 0x00);
+ hid_set_field(report2->field[0], 2, 0x00);
+ hid_set_field(report2->field[0], 3, 32);
+
+ tdata = vbitmap + (tile * 4 + chip) * 64;
+ for (i = 0; i < 64; i++)
+ if (i < 32)
+ hid_set_field(report1->field[0], 11 + i, tdata[i]);
+ else
+ hid_set_field(report2->field[0], 4 + i - 32, tdata[i]);
+
+ hid_hw_request(data->hdev, report1, HID_REQ_SET_REPORT);
+ hid_hw_request(data->hdev, report2, HID_REQ_SET_REPORT);
+ spin_unlock_irqrestore(&data->lock, flags);
+ return 0;
+}
+
+/* Translate a single tile*/
+static int picolcd_fb_update_tile(u8 *vbitmap, const u8 *bitmap, int bpp,
+ int chip, int tile)
+{
+ int i, b, changed = 0;
+ u8 tdata[64];
+ u8 *vdata = vbitmap + (tile * 4 + chip) * 64;
+
+ if (bpp == 1) {
+ for (b = 7; b >= 0; b--) {
+ const u8 *bdata = bitmap + tile * 256 + chip * 8 + b * 32;
+ for (i = 0; i < 64; i++) {
+ tdata[i] <<= 1;
+ tdata[i] |= (bdata[i/8] >> (i % 8)) & 0x01;
+ }
+ }
+ } else if (bpp == 8) {
+ for (b = 7; b >= 0; b--) {
+ const u8 *bdata = bitmap + (tile * 256 + chip * 8 + b * 32) * 8;
+ for (i = 0; i < 64; i++) {
+ tdata[i] <<= 1;
+ tdata[i] |= (bdata[i] & 0x80) ? 0x01 : 0x00;
+ }
+ }
+ } else {
+ /* Oops, we should never get here! */
+ WARN_ON(1);
+ return 0;
+ }
+
+ for (i = 0; i < 64; i++)
+ if (tdata[i] != vdata[i]) {
+ changed = 1;
+ vdata[i] = tdata[i];
+ }
+ return changed;
+}
+
+void picolcd_fb_refresh(struct picolcd_data *data)
+{
+ if (data->fb_info)
+ schedule_delayed_work(&data->fb_info->deferred_work, 0);
+}
+
+/* Reconfigure LCD display */
+int picolcd_fb_reset(struct picolcd_data *data, int clear)
+{
+ struct hid_report *report = picolcd_out_report(REPORT_LCD_CMD, data->hdev);
+ struct picolcd_fb_data *fbdata = data->fb_info->par;
+ int i, j;
+ unsigned long flags;
+ static const u8 mapcmd[8] = { 0x00, 0x02, 0x00, 0x64, 0x3f, 0x00, 0x64, 0xc0 };
+
+ if (!report || report->maxfield != 1)
+ return -ENODEV;
+
+ spin_lock_irqsave(&data->lock, flags);
+ for (i = 0; i < 4; i++) {
+ for (j = 0; j < report->field[0]->maxusage; j++)
+ if (j == 0)
+ hid_set_field(report->field[0], j, i << 2);
+ else if (j < sizeof(mapcmd))
+ hid_set_field(report->field[0], j, mapcmd[j]);
+ else
+ hid_set_field(report->field[0], j, 0);
+ hid_hw_request(data->hdev, report, HID_REQ_SET_REPORT);
+ }
+ spin_unlock_irqrestore(&data->lock, flags);
+
+ if (clear) {
+ memset(fbdata->vbitmap, 0, PICOLCDFB_SIZE);
+ memset(fbdata->bitmap, 0, PICOLCDFB_SIZE*fbdata->bpp);
+ }
+ fbdata->force = 1;
+
+ /* schedule first output of framebuffer */
+ if (fbdata->ready)
+ schedule_delayed_work(&data->fb_info->deferred_work, 0);
+ else
+ fbdata->ready = 1;
+
+ return 0;
+}
+
+/* Update fb_vbitmap from the screen_base and send changed tiles to device */
+static void picolcd_fb_update(struct fb_info *info)
+{
+ int chip, tile, n;
+ unsigned long flags;
+ struct picolcd_fb_data *fbdata = info->par;
+ struct picolcd_data *data;
+
+ mutex_lock(&info->lock);
+
+ spin_lock_irqsave(&fbdata->lock, flags);
+ if (!fbdata->ready && fbdata->picolcd)
+ picolcd_fb_reset(fbdata->picolcd, 0);
+ spin_unlock_irqrestore(&fbdata->lock, flags);
+
+ /*
+ * Translate the framebuffer into the format needed by the PicoLCD.
+ * See display layout above.
+ * Do this one tile after the other and push those tiles that changed.
+ *
+ * Wait for our IO to complete as otherwise we might flood the queue!
+ */
+ n = 0;
+ for (chip = 0; chip < 4; chip++)
+ for (tile = 0; tile < 8; tile++) {
+ if (!fbdata->force && !picolcd_fb_update_tile(
+ fbdata->vbitmap, fbdata->bitmap,
+ fbdata->bpp, chip, tile))
+ continue;
+ n += 2;
+ if (n >= HID_OUTPUT_FIFO_SIZE / 2) {
+ spin_lock_irqsave(&fbdata->lock, flags);
+ data = fbdata->picolcd;
+ spin_unlock_irqrestore(&fbdata->lock, flags);
+ mutex_unlock(&info->lock);
+ if (!data)
+ return;
+ hid_hw_wait(data->hdev);
+ mutex_lock(&info->lock);
+ n = 0;
+ }
+ spin_lock_irqsave(&fbdata->lock, flags);
+ data = fbdata->picolcd;
+ spin_unlock_irqrestore(&fbdata->lock, flags);
+ if (!data || picolcd_fb_send_tile(data,
+ fbdata->vbitmap, chip, tile))
+ goto out;
+ }
+ fbdata->force = false;
+ if (n) {
+ spin_lock_irqsave(&fbdata->lock, flags);
+ data = fbdata->picolcd;
+ spin_unlock_irqrestore(&fbdata->lock, flags);
+ mutex_unlock(&info->lock);
+ if (data)
+ hid_hw_wait(data->hdev);
+ return;
+ }
+out:
+ mutex_unlock(&info->lock);
+}
+
+/* Stub to call the system default and update the image on the picoLCD */
+static void picolcd_fb_fillrect(struct fb_info *info,
+ const struct fb_fillrect *rect)
+{
+ if (!info->par)
+ return;
+ sys_fillrect(info, rect);
+
+ schedule_delayed_work(&info->deferred_work, 0);
+}
+
+/* Stub to call the system default and update the image on the picoLCD */
+static void picolcd_fb_copyarea(struct fb_info *info,
+ const struct fb_copyarea *area)
+{
+ if (!info->par)
+ return;
+ sys_copyarea(info, area);
+
+ schedule_delayed_work(&info->deferred_work, 0);
+}
+
+/* Stub to call the system default and update the image on the picoLCD */
+static void picolcd_fb_imageblit(struct fb_info *info, const struct fb_image *image)
+{
+ if (!info->par)
+ return;
+ sys_imageblit(info, image);
+
+ schedule_delayed_work(&info->deferred_work, 0);
+}
+
+/*
+ * this is the slow path from userspace. they can seek and write to
+ * the fb. it's inefficient to do anything less than a full screen draw
+ */
+static ssize_t picolcd_fb_write(struct fb_info *info, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ ssize_t ret;
+ if (!info->par)
+ return -ENODEV;
+ ret = fb_sys_write(info, buf, count, ppos);
+ if (ret >= 0)
+ schedule_delayed_work(&info->deferred_work, 0);
+ return ret;
+}
+
+static int picolcd_fb_blank(int blank, struct fb_info *info)
+{
+ /* We let fb notification do this for us via lcd/backlight device */
+ return 0;
+}
+
+static void picolcd_fb_destroy(struct fb_info *info)
+{
+ struct picolcd_fb_data *fbdata = info->par;
+
+ /* make sure no work is deferred */
+ fb_deferred_io_cleanup(info);
+
+ /* No thridparty should ever unregister our framebuffer! */
+ WARN_ON(fbdata->picolcd != NULL);
+
+ vfree((u8 *)info->fix.smem_start);
+ framebuffer_release(info);
+}
+
+static int picolcd_fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
+{
+ __u32 bpp = var->bits_per_pixel;
+ __u32 activate = var->activate;
+
+ /* only allow 1/8 bit depth (8-bit is grayscale) */
+ *var = picolcdfb_var;
+ var->activate = activate;
+ if (bpp >= 8) {
+ var->bits_per_pixel = 8;
+ var->red.length = 8;
+ var->green.length = 8;
+ var->blue.length = 8;
+ } else {
+ var->bits_per_pixel = 1;
+ var->red.length = 1;
+ var->green.length = 1;
+ var->blue.length = 1;
+ }
+ return 0;
+}
+
+static int picolcd_set_par(struct fb_info *info)
+{
+ struct picolcd_fb_data *fbdata = info->par;
+ u8 *tmp_fb, *o_fb;
+ if (info->var.bits_per_pixel == fbdata->bpp)
+ return 0;
+ /* switch between 1/8 bit depths */
+ if (info->var.bits_per_pixel != 1 && info->var.bits_per_pixel != 8)
+ return -EINVAL;
+
+ o_fb = fbdata->bitmap;
+ tmp_fb = kmalloc_array(PICOLCDFB_SIZE, info->var.bits_per_pixel,
+ GFP_KERNEL);
+ if (!tmp_fb)
+ return -ENOMEM;
+
+ /* translate FB content to new bits-per-pixel */
+ if (info->var.bits_per_pixel == 1) {
+ int i, b;
+ for (i = 0; i < PICOLCDFB_SIZE; i++) {
+ u8 p = 0;
+ for (b = 0; b < 8; b++) {
+ p <<= 1;
+ p |= o_fb[i*8+b] ? 0x01 : 0x00;
+ }
+ tmp_fb[i] = p;
+ }
+ memcpy(o_fb, tmp_fb, PICOLCDFB_SIZE);
+ info->fix.visual = FB_VISUAL_MONO01;
+ info->fix.line_length = PICOLCDFB_WIDTH / 8;
+ } else {
+ int i;
+ memcpy(tmp_fb, o_fb, PICOLCDFB_SIZE);
+ for (i = 0; i < PICOLCDFB_SIZE * 8; i++)
+ o_fb[i] = tmp_fb[i/8] & (0x01 << (7 - i % 8)) ? 0xff : 0x00;
+ info->fix.visual = FB_VISUAL_DIRECTCOLOR;
+ info->fix.line_length = PICOLCDFB_WIDTH;
+ }
+
+ kfree(tmp_fb);
+ fbdata->bpp = info->var.bits_per_pixel;
+ return 0;
+}
+
+static const struct fb_ops picolcdfb_ops = {
+ .owner = THIS_MODULE,
+ .fb_destroy = picolcd_fb_destroy,
+ .fb_read = fb_sys_read,
+ .fb_write = picolcd_fb_write,
+ .fb_blank = picolcd_fb_blank,
+ .fb_fillrect = picolcd_fb_fillrect,
+ .fb_copyarea = picolcd_fb_copyarea,
+ .fb_imageblit = picolcd_fb_imageblit,
+ .fb_check_var = picolcd_fb_check_var,
+ .fb_set_par = picolcd_set_par,
+ .fb_mmap = fb_deferred_io_mmap,
+};
+
+
+/* Callback from deferred IO workqueue */
+static void picolcd_fb_deferred_io(struct fb_info *info, struct list_head *pagereflist)
+{
+ picolcd_fb_update(info);
+}
+
+static const struct fb_deferred_io picolcd_fb_defio = {
+ .delay = HZ / PICOLCDFB_UPDATE_RATE_DEFAULT,
+ .deferred_io = picolcd_fb_deferred_io,
+};
+
+
+/*
+ * The "fb_update_rate" sysfs attribute
+ */
+static ssize_t picolcd_fb_update_rate_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct picolcd_data *data = dev_get_drvdata(dev);
+ struct picolcd_fb_data *fbdata = data->fb_info->par;
+ unsigned i, fb_update_rate = fbdata->update_rate;
+ size_t ret = 0;
+
+ for (i = 1; i <= PICOLCDFB_UPDATE_RATE_LIMIT; i++)
+ if (ret >= PAGE_SIZE)
+ break;
+ else if (i == fb_update_rate)
+ ret += scnprintf(buf+ret, PAGE_SIZE-ret, "[%u] ", i);
+ else
+ ret += scnprintf(buf+ret, PAGE_SIZE-ret, "%u ", i);
+ if (ret > 0)
+ buf[min(ret, (size_t)PAGE_SIZE)-1] = '\n';
+ return ret;
+}
+
+static ssize_t picolcd_fb_update_rate_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t count)
+{
+ struct picolcd_data *data = dev_get_drvdata(dev);
+ struct picolcd_fb_data *fbdata = data->fb_info->par;
+ int i;
+ unsigned u;
+
+ if (count < 1 || count > 10)
+ return -EINVAL;
+
+ i = sscanf(buf, "%u", &u);
+ if (i != 1)
+ return -EINVAL;
+
+ if (u > PICOLCDFB_UPDATE_RATE_LIMIT)
+ return -ERANGE;
+ else if (u == 0)
+ u = PICOLCDFB_UPDATE_RATE_DEFAULT;
+
+ fbdata->update_rate = u;
+ data->fb_info->fbdefio->delay = HZ / fbdata->update_rate;
+ return count;
+}
+
+static DEVICE_ATTR(fb_update_rate, 0664, picolcd_fb_update_rate_show,
+ picolcd_fb_update_rate_store);
+
+/* initialize Framebuffer device */
+int picolcd_init_framebuffer(struct picolcd_data *data)
+{
+ struct device *dev = &data->hdev->dev;
+ struct fb_info *info = NULL;
+ struct picolcd_fb_data *fbdata = NULL;
+ int i, error = -ENOMEM;
+ u32 *palette;
+
+ /* The extra memory is:
+ * - 256*u32 for pseudo_palette
+ * - struct fb_deferred_io
+ */
+ info = framebuffer_alloc(256 * sizeof(u32) +
+ sizeof(struct fb_deferred_io) +
+ sizeof(struct picolcd_fb_data) +
+ PICOLCDFB_SIZE, dev);
+ if (!info)
+ goto err_nomem;
+
+ info->fbdefio = info->par;
+ *info->fbdefio = picolcd_fb_defio;
+ info->par += sizeof(struct fb_deferred_io);
+ palette = info->par;
+ info->par += 256 * sizeof(u32);
+ for (i = 0; i < 256; i++)
+ palette[i] = i > 0 && i < 16 ? 0xff : 0;
+ info->pseudo_palette = palette;
+ info->fbops = &picolcdfb_ops;
+ info->var = picolcdfb_var;
+ info->fix = picolcdfb_fix;
+ info->fix.smem_len = PICOLCDFB_SIZE*8;
+ info->flags = FBINFO_FLAG_DEFAULT;
+
+ fbdata = info->par;
+ spin_lock_init(&fbdata->lock);
+ fbdata->picolcd = data;
+ fbdata->update_rate = PICOLCDFB_UPDATE_RATE_DEFAULT;
+ fbdata->bpp = picolcdfb_var.bits_per_pixel;
+ fbdata->force = 1;
+ fbdata->vbitmap = info->par + sizeof(struct picolcd_fb_data);
+ fbdata->bitmap = vmalloc(PICOLCDFB_SIZE*8);
+ if (fbdata->bitmap == NULL) {
+ dev_err(dev, "can't get a free page for framebuffer\n");
+ goto err_nomem;
+ }
+ info->screen_base = (char __force __iomem *)fbdata->bitmap;
+ info->fix.smem_start = (unsigned long)fbdata->bitmap;
+ memset(fbdata->vbitmap, 0xff, PICOLCDFB_SIZE);
+ data->fb_info = info;
+
+ error = picolcd_fb_reset(data, 1);
+ if (error) {
+ dev_err(dev, "failed to configure display\n");
+ goto err_cleanup;
+ }
+
+ error = device_create_file(dev, &dev_attr_fb_update_rate);
+ if (error) {
+ dev_err(dev, "failed to create sysfs attributes\n");
+ goto err_cleanup;
+ }
+
+ fb_deferred_io_init(info);
+ error = register_framebuffer(info);
+ if (error) {
+ dev_err(dev, "failed to register framebuffer\n");
+ goto err_sysfs;
+ }
+ return 0;
+
+err_sysfs:
+ device_remove_file(dev, &dev_attr_fb_update_rate);
+ fb_deferred_io_cleanup(info);
+err_cleanup:
+ data->fb_info = NULL;
+
+err_nomem:
+ if (fbdata)
+ vfree(fbdata->bitmap);
+ framebuffer_release(info);
+ return error;
+}
+
+void picolcd_exit_framebuffer(struct picolcd_data *data)
+{
+ struct fb_info *info = data->fb_info;
+ struct picolcd_fb_data *fbdata;
+ unsigned long flags;
+
+ if (!info)
+ return;
+
+ device_remove_file(&data->hdev->dev, &dev_attr_fb_update_rate);
+ fbdata = info->par;
+
+ /* disconnect framebuffer from HID dev */
+ spin_lock_irqsave(&fbdata->lock, flags);
+ fbdata->picolcd = NULL;
+ spin_unlock_irqrestore(&fbdata->lock, flags);
+
+ /* make sure there is no running update - thus that fbdata->picolcd
+ * once obtained under lock is guaranteed not to get free() under
+ * the feet of the deferred work */
+ flush_delayed_work(&info->deferred_work);
+
+ data->fb_info = NULL;
+ unregister_framebuffer(info);
+}
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