From 106b4a2a78b2a2f14885604891957b84bba502db Mon Sep 17 00:00:00 2001 From: Adrian Betschart Date: Fri, 11 Sep 2026 17:13:14 +0200 Subject: drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validation amdgpu_dm_create_validate_stream_for_sink() walks encoding_order[] and uses the first encoding that validates. YCbCr 4:4:4 is listed before RGB, so an HDMI sink that advertises 4:4:4 gets YCbCr 4:4:4 whenever the "color format" property is left at AUTO, even though RGB fits the same link. That contradicts the documented AUTO behaviour for HDMI in enum drm_connector_color_format (RGB, falling back to YCbCr 4:2:0 only when the bandwidth is not available or the mode is 4:2:0-only), which the amdgpu implementation of the property also describes. It also leaves the "Broadcast RGB" property without effect on such sinks, since the quantization range it selects only applies to RGB output. Try RGB first. The mask still holds every encoding the sink supports, so a mode that cannot carry RGB falls back exactly as before. For reference, v7.2 picked RGB here unless YCbCr 4:4:4 was forced through debugfs, while earlier kernels picked YCbCr 4:4:4 for any HDMI sink that advertised it. Fixes: 0b0ff65d3ca1 ("drm/amd/display: Refactor stream validation") Suggested-by: Adolfo Rodrigues Assisted-by: Claude Code:claude-fable-5-1 Signed-off-by: Adrian Betschart Reviewed-by: Fangzhi Zuo Tested-by: Adolfo Rodrigues Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher (cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7) --- drivers/input/touchscreen/touchwin.c | 184 +++++++++++++++++++++++++++++++++++ 1 file changed, 184 insertions(+) create mode 100644 drivers/input/touchscreen/touchwin.c (limited to 'drivers/input/touchscreen/touchwin.c') diff --git a/drivers/input/touchscreen/touchwin.c b/drivers/input/touchscreen/touchwin.c new file mode 100644 index 000000000..3ed33378d --- /dev/null +++ b/drivers/input/touchscreen/touchwin.c @@ -0,0 +1,184 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Touchwindow serial touchscreen driver + * + * Copyright (c) 2006 Rick Koch + * + * Based on MicroTouch driver (drivers/input/touchscreen/mtouch.c) + * Copyright (c) 2004 Vojtech Pavlik + * and Dan Streetman + */ + + +/* + * 2005/02/19 Rick Koch: + * The Touchwindow I used is made by Edmark Corp. and + * constantly outputs a stream of 0's unless it is touched. + * It then outputs 3 bytes: X, Y, and a copy of Y. + */ + +#include +#include +#include +#include +#include +#include + +#define DRIVER_DESC "Touchwindow serial touchscreen driver" + +MODULE_AUTHOR("Rick Koch "); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); + +/* + * Definitions & global arrays. + */ + +#define TW_LENGTH 3 + +#define TW_MIN_XC 0 +#define TW_MAX_XC 0xff +#define TW_MIN_YC 0 +#define TW_MAX_YC 0xff + +/* + * Per-touchscreen data. + */ + +struct tw { + struct input_dev *dev; + struct serio *serio; + int idx; + int touched; + unsigned char data[TW_LENGTH]; + char phys[32]; +}; + +static irqreturn_t tw_interrupt(struct serio *serio, + unsigned char data, unsigned int flags) +{ + struct tw *tw = serio_get_drvdata(serio); + struct input_dev *dev = tw->dev; + + if (data) { /* touch */ + tw->touched = 1; + tw->data[tw->idx++] = data; + /* a full packet ends the accumulation, valid or not */ + if (tw->idx == TW_LENGTH) { + /* report only if the two Y's are the same */ + if (tw->data[1] == tw->data[2]) { + input_report_abs(dev, ABS_X, tw->data[0]); + input_report_abs(dev, ABS_Y, tw->data[1]); + input_report_key(dev, BTN_TOUCH, 1); + input_sync(dev); + } + tw->idx = 0; + } + } else if (tw->touched) { /* untouch */ + input_report_key(dev, BTN_TOUCH, 0); + input_sync(dev); + tw->idx = 0; + tw->touched = 0; + } + + return IRQ_HANDLED; +} + +/* + * tw_disconnect() is the opposite of tw_connect() + */ + +static void tw_disconnect(struct serio *serio) +{ + struct tw *tw = serio_get_drvdata(serio); + + input_get_device(tw->dev); + input_unregister_device(tw->dev); + serio_close(serio); + serio_set_drvdata(serio, NULL); + input_put_device(tw->dev); + kfree(tw); +} + +/* + * tw_connect() is the routine that is called when someone adds a + * new serio device that supports the Touchwin protocol and registers it as + * an input device. + */ + +static int tw_connect(struct serio *serio, struct serio_driver *drv) +{ + struct tw *tw; + struct input_dev *input_dev; + int err; + + tw = kzalloc_obj(*tw); + input_dev = input_allocate_device(); + if (!tw || !input_dev) { + err = -ENOMEM; + goto fail1; + } + + tw->serio = serio; + tw->dev = input_dev; + scnprintf(tw->phys, sizeof(tw->phys), "%s/input0", serio->phys); + + input_dev->name = "Touchwindow Serial TouchScreen"; + input_dev->phys = tw->phys; + input_dev->id.bustype = BUS_RS232; + input_dev->id.vendor = SERIO_TOUCHWIN; + input_dev->id.product = 0; + input_dev->id.version = 0x0100; + input_dev->dev.parent = &serio->dev; + input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); + input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); + input_set_abs_params(tw->dev, ABS_X, TW_MIN_XC, TW_MAX_XC, 0, 0); + input_set_abs_params(tw->dev, ABS_Y, TW_MIN_YC, TW_MAX_YC, 0, 0); + + serio_set_drvdata(serio, tw); + + err = serio_open(serio, drv); + if (err) + goto fail2; + + err = input_register_device(tw->dev); + if (err) + goto fail3; + + return 0; + + fail3: serio_close(serio); + fail2: serio_set_drvdata(serio, NULL); + fail1: input_free_device(input_dev); + kfree(tw); + return err; +} + +/* + * The serio driver structure. + */ + +static const struct serio_device_id tw_serio_ids[] = { + { + .type = SERIO_RS232, + .proto = SERIO_TOUCHWIN, + .id = SERIO_ANY, + .extra = SERIO_ANY, + }, + { 0 } +}; + +MODULE_DEVICE_TABLE(serio, tw_serio_ids); + +static struct serio_driver tw_drv = { + .driver = { + .name = "touchwin", + }, + .description = DRIVER_DESC, + .id_table = tw_serio_ids, + .interrupt = tw_interrupt, + .connect = tw_connect, + .disconnect = tw_disconnect, +}; + +module_serio_driver(tw_drv); -- cgit v1.3.1