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/elo.c | 406 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 406 insertions(+) create mode 100644 drivers/input/touchscreen/elo.c (limited to 'drivers/input/touchscreen/elo.c') diff --git a/drivers/input/touchscreen/elo.c b/drivers/input/touchscreen/elo.c new file mode 100644 index 000000000..97aeec7ef --- /dev/null +++ b/drivers/input/touchscreen/elo.c @@ -0,0 +1,406 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Elo serial touchscreen driver + * + * Copyright (c) 2004 Vojtech Pavlik + */ + + +/* + * This driver can handle serial Elo touchscreens using either the Elo standard + * 'E271-2210' 10-byte protocol, Elo legacy 'E281A-4002' 6-byte protocol, Elo + * legacy 'E271-140' 4-byte protocol and Elo legacy 'E261-280' 3-byte protocol. + */ + +#include +#include +#include +#include +#include +#include +#include + +#define DRIVER_DESC "Elo serial touchscreen driver" + +MODULE_AUTHOR("Vojtech Pavlik "); +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_LICENSE("GPL"); + +/* + * Definitions & global arrays. + */ + +#define ELO_MAX_LENGTH 10 + +#define ELO10_PACKET_LEN 8 +#define ELO10_TOUCH 0x03 +#define ELO10_PRESSURE 0x80 + +#define ELO10_LEAD_BYTE 'U' + +#define ELO10_ID_CMD 'i' + +#define ELO10_TOUCH_PACKET 'T' +#define ELO10_ACK_PACKET 'A' +#define ELI10_ID_PACKET 'I' + +/* + * Per-touchscreen data. + */ + +struct elo { + struct input_dev *dev; + struct serio *serio; + struct mutex cmd_mutex; + struct completion cmd_done; + int id; + int idx; + unsigned char expected_packet; + unsigned char csum; + unsigned char data[ELO_MAX_LENGTH]; + unsigned char response[ELO10_PACKET_LEN]; + char phys[32]; +}; + +static void elo_process_data_10(struct elo *elo, unsigned char data) +{ + struct input_dev *dev = elo->dev; + + elo->data[elo->idx] = data; + + switch (elo->idx++) { + case 0: + elo->csum = 0xaa; + if (data != ELO10_LEAD_BYTE) { + dev_dbg(&elo->serio->dev, + "unsynchronized data: 0x%02x\n", data); + elo->idx = 0; + } + break; + + case 9: + elo->idx = 0; + if (data != elo->csum) { + dev_dbg(&elo->serio->dev, + "bad checksum: 0x%02x, expected 0x%02x\n", + data, elo->csum); + break; + } + if (elo->data[1] != elo->expected_packet) { + if (elo->data[1] != ELO10_TOUCH_PACKET) + dev_dbg(&elo->serio->dev, + "unexpected packet: 0x%02x\n", + elo->data[1]); + break; + } + if (likely(elo->data[1] == ELO10_TOUCH_PACKET)) { + input_report_abs(dev, ABS_X, (elo->data[4] << 8) | elo->data[3]); + input_report_abs(dev, ABS_Y, (elo->data[6] << 8) | elo->data[5]); + if (elo->data[2] & ELO10_PRESSURE) + input_report_abs(dev, ABS_PRESSURE, + (elo->data[8] << 8) | elo->data[7]); + input_report_key(dev, BTN_TOUCH, elo->data[2] & ELO10_TOUCH); + input_sync(dev); + } else if (elo->data[1] == ELO10_ACK_PACKET) { + if (elo->data[2] == '0') + elo->expected_packet = ELO10_TOUCH_PACKET; + complete(&elo->cmd_done); + } else { + memcpy(elo->response, &elo->data[1], ELO10_PACKET_LEN); + elo->expected_packet = ELO10_ACK_PACKET; + } + break; + } + elo->csum += data; +} + +static void elo_process_data_6(struct elo *elo, unsigned char data) +{ + struct input_dev *dev = elo->dev; + + elo->data[elo->idx] = data; + + switch (elo->idx++) { + + case 0: + if ((data & 0xc0) != 0xc0) + elo->idx = 0; + break; + + case 1: + if ((data & 0xc0) != 0x80) + elo->idx = 0; + break; + + case 2: + if ((data & 0xc0) != 0x40) + elo->idx = 0; + break; + + case 3: + if (data & 0xc0) { + elo->idx = 0; + break; + } + + input_report_abs(dev, ABS_X, ((elo->data[0] & 0x3f) << 6) | (elo->data[1] & 0x3f)); + input_report_abs(dev, ABS_Y, ((elo->data[2] & 0x3f) << 6) | (elo->data[3] & 0x3f)); + + if (elo->id == 2) { + input_report_key(dev, BTN_TOUCH, 1); + input_sync(dev); + elo->idx = 0; + } + + break; + + case 4: + if (data) { + input_sync(dev); + elo->idx = 0; + } + break; + + case 5: + if ((data & 0xf0) == 0) { + input_report_abs(dev, ABS_PRESSURE, elo->data[5]); + input_report_key(dev, BTN_TOUCH, !!elo->data[5]); + } + input_sync(dev); + elo->idx = 0; + break; + } +} + +static void elo_process_data_3(struct elo *elo, unsigned char data) +{ + struct input_dev *dev = elo->dev; + + elo->data[elo->idx] = data; + + switch (elo->idx++) { + + case 0: + if ((data & 0x7f) != 0x01) + elo->idx = 0; + break; + case 2: + input_report_key(dev, BTN_TOUCH, !(elo->data[1] & 0x80)); + input_report_abs(dev, ABS_X, elo->data[1]); + input_report_abs(dev, ABS_Y, elo->data[2]); + input_sync(dev); + elo->idx = 0; + break; + } +} + +static irqreturn_t elo_interrupt(struct serio *serio, + unsigned char data, unsigned int flags) +{ + struct elo *elo = serio_get_drvdata(serio); + + switch (elo->id) { + case 0: + elo_process_data_10(elo, data); + break; + + case 1: + case 2: + elo_process_data_6(elo, data); + break; + + case 3: + elo_process_data_3(elo, data); + break; + } + + return IRQ_HANDLED; +} + +static int elo_command_10(struct elo *elo, unsigned char *packet) +{ + int error; + int i; + unsigned char csum = 0xaa + ELO10_LEAD_BYTE; + + guard(mutex)(&elo->cmd_mutex); + + scoped_guard(serio_pause_rx, elo->serio) { + elo->expected_packet = toupper(packet[0]); + init_completion(&elo->cmd_done); + } + + error = serio_write(elo->serio, ELO10_LEAD_BYTE); + if (error) + return error; + + for (i = 0; i < ELO10_PACKET_LEN; i++) { + csum += packet[i]; + error = serio_write(elo->serio, packet[i]); + if (error) + return error; + } + + error = serio_write(elo->serio, csum); + if (error) + return error; + + wait_for_completion_timeout(&elo->cmd_done, HZ); + + if (elo->expected_packet != ELO10_TOUCH_PACKET) + return -EIO; + + /* We are back in reporting mode, the command was ACKed */ + memcpy(packet, elo->response, ELO10_PACKET_LEN); + return 0; +} + +static int elo_setup_10(struct elo *elo) +{ + static const char * const elo_types[] = { "Accu", "Dura", "Intelli", "Carroll" }; + struct input_dev *dev = elo->dev; + unsigned char packet[ELO10_PACKET_LEN] = { ELO10_ID_CMD }; + + if (elo_command_10(elo, packet)) + return -1; + + dev->id.version = (packet[5] << 8) | packet[4]; + + input_set_abs_params(dev, ABS_X, 96, 4000, 0, 0); + input_set_abs_params(dev, ABS_Y, 96, 4000, 0, 0); + if (packet[3] & ELO10_PRESSURE) + input_set_abs_params(dev, ABS_PRESSURE, 0, 255, 0, 0); + + dev_info(&elo->serio->dev, + "%sTouch touchscreen, fw: %02x.%02x, features: 0x%02x, controller: 0x%02x\n", + elo_types[(packet[1] - '0') & 0x03], + packet[5], packet[4], packet[3], packet[7]); + + return 0; +} + +/* + * elo_disconnect() is the opposite of elo_connect() + */ + +static void elo_disconnect(struct serio *serio) +{ + struct elo *elo = serio_get_drvdata(serio); + + input_get_device(elo->dev); + input_unregister_device(elo->dev); + serio_close(serio); + serio_set_drvdata(serio, NULL); + input_put_device(elo->dev); + kfree(elo); +} + +/* + * elo_connect() is the routine that is called when someone adds a + * new serio device that supports Gunze protocol and registers it as + * an input device. + */ + +static int elo_connect(struct serio *serio, struct serio_driver *drv) +{ + struct elo *elo; + struct input_dev *input_dev; + int err; + + elo = kzalloc_obj(*elo); + input_dev = input_allocate_device(); + if (!elo || !input_dev) { + err = -ENOMEM; + goto fail1; + } + + elo->serio = serio; + elo->id = serio->id.id; + elo->dev = input_dev; + elo->expected_packet = ELO10_TOUCH_PACKET; + mutex_init(&elo->cmd_mutex); + init_completion(&elo->cmd_done); + scnprintf(elo->phys, sizeof(elo->phys), "%s/input0", serio->phys); + + input_dev->name = "Elo Serial TouchScreen"; + input_dev->phys = elo->phys; + input_dev->id.bustype = BUS_RS232; + input_dev->id.vendor = SERIO_ELO; + input_dev->id.product = elo->id; + 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); + + serio_set_drvdata(serio, elo); + err = serio_open(serio, drv); + if (err) + goto fail2; + + switch (elo->id) { + + case 0: /* 10-byte protocol */ + if (elo_setup_10(elo)) { + err = -EIO; + goto fail3; + } + + break; + + case 1: /* 6-byte protocol */ + input_set_abs_params(input_dev, ABS_PRESSURE, 0, 15, 0, 0); + fallthrough; + + case 2: /* 4-byte protocol */ + input_set_abs_params(input_dev, ABS_X, 96, 4000, 0, 0); + input_set_abs_params(input_dev, ABS_Y, 96, 4000, 0, 0); + break; + + case 3: /* 3-byte protocol */ + input_set_abs_params(input_dev, ABS_X, 0, 255, 0, 0); + input_set_abs_params(input_dev, ABS_Y, 0, 255, 0, 0); + break; + } + + err = input_register_device(elo->dev); + if (err) + goto fail3; + + return 0; + + fail3: serio_close(serio); + fail2: serio_set_drvdata(serio, NULL); + fail1: input_free_device(input_dev); + kfree(elo); + return err; +} + +/* + * The serio driver structure. + */ + +static const struct serio_device_id elo_serio_ids[] = { + { + .type = SERIO_RS232, + .proto = SERIO_ELO, + .id = SERIO_ANY, + .extra = SERIO_ANY, + }, + { 0 } +}; + +MODULE_DEVICE_TABLE(serio, elo_serio_ids); + +static struct serio_driver elo_drv = { + .driver = { + .name = "elo", + }, + .description = DRIVER_DESC, + .id_table = elo_serio_ids, + .interrupt = elo_interrupt, + .connect = elo_connect, + .disconnect = elo_disconnect, +}; + +module_serio_driver(elo_drv); -- cgit v1.3.1