Add framebuffer support to PicoLCD device with use of deferred-io. Only changed areas of framebuffer get sent to device in order to save USB bandwidth and especially resources on PicoLCD device or allow higher refresh rate for a small area. Changed tiles are determined while updating shadow framebuffer. Changes since v2: - add 8bit grayscale depth as near to no userspace app handles 1bit - properly send whole framebuffer on reset/init - drop inline keywords from non-stub functions - use device_{create,remove}_file instead of sysfs_{create,remove}_file Signed-off-by: Bruno Prémont <bonbons@xxxxxxxxxxxxxxxxx> --- Jaya, is my choice of FB_VISUAL_TRUECOLOR correct for grayscale 8bpp mode? Userspace applications I tested with: - links Tested the 8bpp mode, works fine. - fdbsee Fails with a message mentioning font creation, so I assume it's unrelated to my implementation. - fbv Fails and complains about missing color map. That one should not be needed for grayscale unless I'm missing something (documentation is rather poor) I've not tested with Xorg as there is none installed on the test system. drivers/hid/Kconfig | 7 +- drivers/hid/hid-picolcd.c | 544 ++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 549 insertions(+), 2 deletions(-) diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig index 138ba6a..a813ea9 100644 --- a/drivers/hid/Kconfig +++ b/drivers/hid/Kconfig @@ -265,6 +265,11 @@ config HID_PETALYNX config HID_PICOLCD tristate "PicoLCD (graphic version)" depends on USB_HID + select FB_DEFERRED_IO if FB + select FB_SYS_FILLRECT if FB + select FB_SYS_COPYAREA if FB + select FB_SYS_IMAGEBLIT if FB + select FB_SYS_FOPS if FB ---help--- This provides support for Minibox PicoLCD devices, currently only the graphical ones are supported. @@ -272,8 +277,8 @@ config HID_PICOLCD This includes support for the following device features: - Keypad - Switching between Firmware and Flash mode - Features that are not (yet) supported: - Framebuffer for monochrome 256x64 display + Features that are not (yet) supported: - Backlight control - Contrast control - IR diff --git a/drivers/hid/hid-picolcd.c b/drivers/hid/hid-picolcd.c index 2e4409d..6d17d89 100644 --- a/drivers/hid/hid-picolcd.c +++ b/drivers/hid/hid-picolcd.c @@ -24,6 +24,9 @@ #include "usbhid/usbhid.h" #include <linux/usb.h> +#include <linux/fb.h> +#include <linux/vmalloc.h> + #include <linux/seq_file.h> #include <linux/debugfs.h> @@ -69,6 +72,59 @@ #define REPORT_HOOK_VERSION 0xf7 /* LCD: IN[2], OUT[1] */ #define REPORT_EXIT_FLASHER 0xff /* Bootloader: OUT[2] */ +#if defined(CONFIG_FB) || defined(CONFIG_FB_MODULE) +/* 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, +}; +#endif /* CONFIG_FB */ + /* Input device * * The PicoLCD has an IR receiver header, a built-in keypad with 5 keys @@ -118,6 +174,16 @@ struct picolcd_data { struct input_dev *input_cir; unsigned short keycode[PICOLCD_KEYS]; +#if defined(CONFIG_FB) || defined(CONFIG_FB_MODULE) + /* Framebuffer stuff */ + u8 fb_update_rate; + u8 fb_bpp; + u8 *fb_vbitmap; /* local copy of what was sent to PicoLCD */ + u8 *fb_bitmap; /* framebuffer */ + struct fb_info *fb_info; + struct fb_deferred_io fb_defio; +#endif /* CONFIG_FB */ + /* Housekeeping stuff */ spinlock_t lock; struct mutex mutex; @@ -125,6 +191,7 @@ struct picolcd_data { int status; #define PICOLCD_BOOTLOADER 1 #define PICOLCD_FAILED 2 +#define PICOLCD_READY_FB 4 }; @@ -197,6 +264,460 @@ static struct picolcd_pending *picolcd_send_and_wait(struct hid_device *hdev, return work; } +#if defined(CONFIG_FB) || defined(CONFIG_FB_MODULE) +/* Send a given tile to PicoLCD */ +static int picolcd_fb_send_tile(struct hid_device *hdev, int chip, int tile) +{ + struct picolcd_data *data = hid_get_drvdata(hdev); + struct hid_report *report1 = picolcd_out_report(REPORT_LCD_CMD_DATA, hdev); + struct hid_report *report2 = picolcd_out_report(REPORT_LCD_DATA, hdev); + unsigned long flags; + u8 *tdata; + int i; + + if (!report1 || report1->maxfield != 1 || !report2 || report2->maxfield != 1) + return -ENODEV; + + spin_lock_irqsave(&data->lock, flags); + 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 = data->fb_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]); + + usbhid_submit_report(data->hdev, report1, USB_DIR_OUT); + usbhid_submit_report(data->hdev, report2, USB_DIR_OUT); + 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] >> (7 - 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; +} + +/* Reconfigure LCD display */ +static int picolcd_fb_reset(struct picolcd_data *data, int clear) +{ + struct hid_report *report = picolcd_out_report(REPORT_LCD_CMD, data->hdev); + 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); + usbhid_submit_report(data->hdev, report, USB_DIR_OUT); + } + + data->status |= PICOLCD_READY_FB; + spin_unlock_irqrestore(&data->lock, flags); + + if (clear && data->fb_bitmap) { + memset(data->fb_vbitmap, 0xff, PICOLCDFB_SIZE); + memset(data->fb_bitmap, 0, PICOLCDFB_SIZE*data->fb_bpp); + } + + /* schedule first output of framebuffer */ + if (data->fb_info) + schedule_delayed_work(&data->fb_info->deferred_work, 0); + + return 0; +} + +/* Update fb_vbitmap from the screen_base and send changed tiles to device */ +static void picolcd_fb_update(struct picolcd_data *data) +{ + int chip, tile; + unsigned long flags; + + spin_lock_irqsave(&data->lock, flags); + if (!(data->status & PICOLCD_READY_FB)) { + spin_unlock_irqrestore(&data->lock, flags); + picolcd_fb_reset(data, 0); + } else { + spin_unlock_irqrestore(&data->lock, flags); + } + + /* + * Translate the XBM format screen_base into the format needed by the + * PicoLCD. See display layout above. + * Do this one tile after the other and push those tiles that changed. + */ + for (chip = 0; chip < 4; chip++) + for (tile = 0; tile < 8; tile++) + if (picolcd_fb_update_tile(data->fb_vbitmap, + data->fb_bitmap, data->fb_bpp, chip, tile)) + picolcd_fb_send_tile(data->hdev, chip, tile); +} + +/* 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) +{ + if (!info->par) + return -ENODEV; + /* 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_data *data = info->par; + info->par = NULL; + if (data) + data->fb_info = NULL; + fb_deferred_io_cleanup(info); + 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; + else + var->bits_per_pixel = 1; + return 0; +} + +static int picolcd_set_par(struct fb_info *info) +{ + struct picolcd_data *data = info->par; + u8 *o_fb, *n_fb; + if (info->var.bits_per_pixel == data->fb_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 = data->fb_bitmap; + n_fb = vmalloc(PICOLCDFB_SIZE*info->var.bits_per_pixel); + if (!n_fb) + return -ENOMEM; + + fb_deferred_io_cleanup(info); + /* 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; + } + } + info->fix.visual = FB_VISUAL_MONO01; + info->fix.line_length = PICOLCDFB_WIDTH / 8; + } else { + int i; + for (i = 0; i < PICOLCDFB_SIZE * 8; i++) + n_fb[i] = o_fb[i/8] & (0x01 << (7 - i % 8)) ? 0xff : 0x00; + info->fix.visual = FB_VISUAL_TRUECOLOR; + info->fix.line_length = PICOLCDFB_WIDTH; + } + + data->fb_bitmap = n_fb; + data->fb_bpp = info->var.bits_per_pixel; + info->screen_base = (char __force __iomem *)n_fb; + info->fix.smem_start = (unsigned long)n_fb; + info->fix.smem_len = PICOLCDFB_SIZE*data->fb_bpp; + fb_deferred_io_init(info); + vfree(o_fb); + return 0; +} + +/* Note this can't be const because of struct fb_info definition */ +static 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, +}; + + +/* Callback from deferred IO workqueue */ +static void picolcd_fb_deferred_io(struct fb_info *info, struct list_head *pagelist) +{ + picolcd_fb_update(info->par); +} + +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); + unsigned fb_update_rate = data->fb_update_rate; + + return snprintf(buf, PAGE_SIZE, "%u (1..%u)\n", fb_update_rate, + PICOLCDFB_UPDATE_RATE_LIMIT); +} + +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); + 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; + + data->fb_update_rate = u; + data->fb_defio.delay = HZ / data->fb_update_rate; + return count; +} + +static DEVICE_ATTR(fb_update_rate, 0666, picolcd_fb_update_rate_show, + picolcd_fb_update_rate_store); + +/* initialize Framebuffer device */ +static int picolcd_init_framebuffer(struct picolcd_data *data) +{ + struct device *dev = &data->hdev->dev; + struct fb_info *info = NULL; + int error = -ENOMEM; + u8 *fb_vbitmap = NULL; + u8 *fb_bitmap = NULL; + + fb_bitmap = vmalloc(PICOLCDFB_SIZE*picolcdfb_var.bits_per_pixel); + if (fb_bitmap == NULL) { + dev_err(dev, "can't get a free page for framebuffer\n"); + goto err_nomem; + } + + fb_vbitmap = kmalloc(PICOLCDFB_SIZE, GFP_KERNEL); + if (fb_vbitmap == NULL) { + dev_err(dev, "can't alloc vbitmap image buffer\n"); + goto err_nomem; + } + + data->fb_update_rate = PICOLCDFB_UPDATE_RATE_DEFAULT; + data->fb_defio = picolcd_fb_defio; + info = framebuffer_alloc(0, dev); + if (info == NULL) { + dev_err(dev, "failed to allocate a framebuffer\n"); + goto err_nomem; + } + + info->fbdefio = &data->fb_defio; + info->screen_base = (char __force __iomem *)fb_bitmap; + info->fbops = &picolcdfb_ops; + info->var = picolcdfb_var; + info->fix = picolcdfb_fix; + info->fix.smem_len = PICOLCDFB_SIZE; + info->fix.smem_start = (unsigned long)fb_bitmap; + info->par = data; + info->flags = FBINFO_FLAG_DEFAULT; + + data->fb_vbitmap = fb_vbitmap; + data->fb_bitmap = fb_bitmap; + data->fb_bpp = picolcdfb_var.bits_per_pixel; + 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; + } + data->fb_info = info; + error = register_framebuffer(info); + if (error) { + dev_err(dev, "failed to register framebuffer\n"); + goto err_sysfs; + } + fb_deferred_io_init(info); + /* schedule first output of framebuffer */ + schedule_delayed_work(&info->deferred_work, 0); + return 0; + +err_sysfs: + device_remove_file(dev, &dev_attr_fb_update_rate); +err_cleanup: + data->fb_vbitmap = NULL; + data->fb_bitmap = NULL; + data->fb_bpp = 0; + data->fb_info = NULL; + +err_nomem: + framebuffer_release(info); + vfree(fb_bitmap); + kfree(fb_vbitmap); + return error; +} + +static void picolcd_exit_framebuffer(struct picolcd_data *data) +{ + struct fb_info *info = data->fb_info; + u8 *fb_vbitmap = data->fb_vbitmap; + u8 *fb_bitmap = data->fb_bitmap; + + if (!info) + return; + + data->fb_vbitmap = NULL; + data->fb_bitmap = NULL; + data->fb_bpp = 0; + data->fb_info = NULL; + device_remove_file(&data->hdev->dev, &dev_attr_fb_update_rate); + fb_deferred_io_cleanup(info); + unregister_framebuffer(info); + vfree(fb_bitmap); + kfree(fb_vbitmap); +} + + +#else +static inline int picolcd_fb_reset(struct picolcd_data *data, int clear) +{ + return 0; +} +static inline int picolcd_init_framebuffer(struct picolcd_data *data) +{ + return 0; +} +static void picolcd_exit_framebuffer(struct picolcd_data *data) +{ +} +#endif /* CONFIG_FB */ + /* * input class device */ @@ -314,6 +835,7 @@ static int picolcd_reset(struct hid_device *hdev) struct picolcd_data *data = hid_get_drvdata(hdev); struct hid_report *report = picolcd_out_report(REPORT_RESET, hdev); unsigned long flags; + int error; if (!data || !report || report->maxfield != 1) return -ENODEV; @@ -327,7 +849,16 @@ static int picolcd_reset(struct hid_device *hdev) usbhid_submit_report(hdev, report, USB_DIR_OUT); spin_unlock_irqrestore(&data->lock, flags); - return picolcd_check_version(hdev); + error = picolcd_check_version(hdev); + if (error) + return error; + +#if defined(CONFIG_FB) || defined(CONFIG_FB_MODULE) + if (data->fb_info) + schedule_delayed_work(&data->fb_info->deferred_work, 0); +#endif /* CONFIG_FB */ + + return 0; } /* @@ -931,6 +1462,9 @@ static int picolcd_reset_resume(struct hid_device *hdev) ret = picolcd_reset(hdev); if (ret) dbg_hid(PICOLCD_NAME " resetting our device failed: %d\n", ret); + ret = picolcd_fb_reset(hid_get_drvdata(hdev), 0); + if (ret) + dbg_hid(PICOLCD_NAME " restoring framebuffer content failed: %d\n", ret); return 0; } #endif @@ -1030,6 +1564,11 @@ static int picolcd_probe_lcd(struct hid_device *hdev, struct picolcd_data *data) if (error) goto err; + /* Set up the framebuffer device */ + error = picolcd_init_framebuffer(data); + if (error) + goto err; + #ifdef CONFIG_DEBUG_FS report = picolcd_out_report(REPORT_READ_MEMORY, hdev); if (report && report->maxfield == 1 && report->field[0]->report_size == 8) @@ -1039,6 +1578,7 @@ static int picolcd_probe_lcd(struct hid_device *hdev, struct picolcd_data *data) #endif return 0; err: + picolcd_exit_framebuffer(data); picolcd_exit_cir(data); picolcd_exit_keys(data); return error; @@ -1168,6 +1708,8 @@ static void picolcd_remove(struct hid_device *hdev) complete(&data->pending->ready); spin_unlock_irqrestore(&data->lock, flags); + /* Clean up the framebuffer */ + picolcd_exit_framebuffer(data); /* Cleanup input */ picolcd_exit_cir(data); picolcd_exit_keys(data); -- 1.6.4.4 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html