summaryrefslogtreecommitdiffstats
path: root/drivers/input/touchscreen/raspberrypi-ts.c
diff options
context:
space:
mode:
authorAdrian Betschart <adrian.betschart@cinemaone.ch>2026-09-11 17:13:14 +0200
committerAlex Deucher <alexander.deucher@amd.com>2026-10-01 17:18:05 -0400
commit106b4a2a78b2a2f14885604891957b84bba502db (patch)
tree5d40eef2428fb1a4791ab46a4b19091a5910eac2 /drivers/input/touchscreen/raspberrypi-ts.c
downloadlinux-stable-106b4a2a78b2a2f14885604891957b84bba502db.tar.gz
linux-stable-106b4a2a78b2a2f14885604891957b84bba502db.zip
drm/amd/display: Try RGB before YCbCr 4:4:4 in stream validationgrafted
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 <adolfotregosa@gmail.com> Assisted-by: Claude Code:claude-fable-5-1 Signed-off-by: Adrian Betschart <adrian.betschart@cinemaone.ch> Reviewed-by: Fangzhi Zuo <jerry.zuo@amd.com> Tested-by: Adolfo Rodrigues <adolfotregosa@gmail.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 7de432bc753133764dc40d37f9388da56de251e7)
Diffstat (limited to 'drivers/input/touchscreen/raspberrypi-ts.c')
-rw-r--r--drivers/input/touchscreen/raspberrypi-ts.c226
1 files changed, 226 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/raspberrypi-ts.c b/drivers/input/touchscreen/raspberrypi-ts.c
new file mode 100644
index 000000000..841d39a44
--- /dev/null
+++ b/drivers/input/touchscreen/raspberrypi-ts.c
@@ -0,0 +1,226 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Raspberry Pi firmware based touchscreen driver
+ *
+ * Copyright (C) 2015, 2017 Raspberry Pi
+ * Copyright (C) 2018 Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
+ */
+
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/bitops.h>
+#include <linux/dma-mapping.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
+#include <soc/bcm2835/raspberrypi-firmware.h>
+
+#define RPI_TS_DEFAULT_WIDTH 800
+#define RPI_TS_DEFAULT_HEIGHT 480
+
+#define RPI_TS_MAX_SUPPORTED_POINTS 10
+
+#define RPI_TS_FTS_TOUCH_DOWN 0
+#define RPI_TS_FTS_TOUCH_CONTACT 2
+
+#define RPI_TS_POLL_INTERVAL 17 /* 60fps */
+
+#define RPI_TS_NPOINTS_REG_INVALIDATE 99
+
+struct rpi_ts {
+ struct platform_device *pdev;
+ struct input_dev *input;
+ struct touchscreen_properties prop;
+
+ void __iomem *fw_regs_va;
+ dma_addr_t fw_regs_phys;
+
+ int known_ids;
+};
+
+struct rpi_ts_regs {
+ u8 device_mode;
+ u8 gesture_id;
+ u8 num_points;
+ struct rpi_ts_touch {
+ u8 xh;
+ u8 xl;
+ u8 yh;
+ u8 yl;
+ u8 pressure; /* Not supported */
+ u8 area; /* Not supported */
+ } point[RPI_TS_MAX_SUPPORTED_POINTS];
+};
+
+static void rpi_ts_poll(struct input_dev *input)
+{
+ struct rpi_ts *ts = input_get_drvdata(input);
+ struct rpi_ts_regs regs;
+ int modified_ids = 0;
+ long released_ids;
+ int event_type;
+ int touchid;
+ int x, y;
+ int i;
+
+ memcpy_fromio(&regs, ts->fw_regs_va, sizeof(regs));
+ /*
+ * We poll the memory based register copy of the touchscreen chip using
+ * the number of points register to know whether the copy has been
+ * updated (we write 99 to the memory copy, the GPU will write between
+ * 0 - 10 points)
+ */
+ iowrite8(RPI_TS_NPOINTS_REG_INVALIDATE,
+ ts->fw_regs_va + offsetof(struct rpi_ts_regs, num_points));
+
+ if (regs.num_points == RPI_TS_NPOINTS_REG_INVALIDATE ||
+ (regs.num_points == 0 && ts->known_ids == 0))
+ return;
+
+ for (i = 0; i < regs.num_points; i++) {
+ x = (((int)regs.point[i].xh & 0xf) << 8) + regs.point[i].xl;
+ y = (((int)regs.point[i].yh & 0xf) << 8) + regs.point[i].yl;
+ touchid = (regs.point[i].yh >> 4) & 0xf;
+ event_type = (regs.point[i].xh >> 6) & 0x03;
+
+ modified_ids |= BIT(touchid);
+
+ if (event_type == RPI_TS_FTS_TOUCH_DOWN ||
+ event_type == RPI_TS_FTS_TOUCH_CONTACT) {
+ input_mt_slot(input, touchid);
+ input_mt_report_slot_state(input, MT_TOOL_FINGER, 1);
+ touchscreen_report_pos(input, &ts->prop, x, y, true);
+ }
+ }
+
+ released_ids = ts->known_ids & ~modified_ids;
+ for_each_set_bit(i, &released_ids, RPI_TS_MAX_SUPPORTED_POINTS) {
+ input_mt_slot(input, i);
+ input_mt_report_slot_inactive(input);
+ modified_ids &= ~(BIT(i));
+ }
+ ts->known_ids = modified_ids;
+
+ input_mt_sync_frame(input);
+ input_sync(input);
+}
+
+static void rpi_ts_dma_cleanup(void *data)
+{
+ struct rpi_ts *ts = data;
+ struct device *dev = &ts->pdev->dev;
+
+ dma_free_coherent(dev, PAGE_SIZE, ts->fw_regs_va, ts->fw_regs_phys);
+}
+
+static int rpi_ts_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct input_dev *input;
+ struct rpi_firmware *fw;
+ struct rpi_ts *ts;
+ u32 touchbuf;
+ int error;
+
+ struct device_node *fw_node __free(device_node) = of_get_parent(np);
+ if (!fw_node) {
+ dev_err(dev, "Missing firmware node\n");
+ return -ENOENT;
+ }
+
+ fw = devm_rpi_firmware_get(&pdev->dev, fw_node);
+ if (!fw)
+ return -EPROBE_DEFER;
+
+ ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
+ if (!ts)
+ return -ENOMEM;
+ ts->pdev = pdev;
+
+ ts->fw_regs_va = dma_alloc_coherent(dev, PAGE_SIZE, &ts->fw_regs_phys,
+ GFP_KERNEL);
+ if (!ts->fw_regs_va) {
+ dev_err(dev, "failed to dma_alloc_coherent\n");
+ return -ENOMEM;
+ }
+
+ error = devm_add_action_or_reset(dev, rpi_ts_dma_cleanup, ts);
+ if (error) {
+ dev_err(dev, "failed to devm_add_action_or_reset, %d\n", error);
+ return error;
+ }
+
+ touchbuf = (u32)ts->fw_regs_phys;
+ error = rpi_firmware_property(fw, RPI_FIRMWARE_FRAMEBUFFER_SET_TOUCHBUF,
+ &touchbuf, sizeof(touchbuf));
+ if (error || touchbuf != 0) {
+ dev_warn(dev, "Failed to set touchbuf, %d\n", error);
+ return error;
+ }
+
+ input = devm_input_allocate_device(dev);
+ if (!input) {
+ dev_err(dev, "Failed to allocate input device\n");
+ return -ENOMEM;
+ }
+
+ ts->input = input;
+ input_set_drvdata(input, ts);
+
+ input->name = "raspberrypi-ts";
+ input->id.bustype = BUS_HOST;
+
+ input_set_abs_params(input, ABS_MT_POSITION_X, 0,
+ RPI_TS_DEFAULT_WIDTH, 0, 0);
+ input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
+ RPI_TS_DEFAULT_HEIGHT, 0, 0);
+ touchscreen_parse_properties(input, true, &ts->prop);
+
+ error = input_mt_init_slots(input, RPI_TS_MAX_SUPPORTED_POINTS,
+ INPUT_MT_DIRECT);
+ if (error) {
+ dev_err(dev, "could not init mt slots, %d\n", error);
+ return error;
+ }
+
+ error = input_setup_polling(input, rpi_ts_poll);
+ if (error) {
+ dev_err(dev, "could not set up polling mode, %d\n", error);
+ return error;
+ }
+
+ input_set_poll_interval(input, RPI_TS_POLL_INTERVAL);
+
+ error = input_register_device(input);
+ if (error) {
+ dev_err(dev, "could not register input device, %d\n", error);
+ return error;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id rpi_ts_match[] = {
+ { .compatible = "raspberrypi,firmware-ts", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, rpi_ts_match);
+
+static struct platform_driver rpi_ts_driver = {
+ .driver = {
+ .name = "raspberrypi-ts",
+ .of_match_table = rpi_ts_match,
+ },
+ .probe = rpi_ts_probe,
+};
+module_platform_driver(rpi_ts_driver);
+
+MODULE_AUTHOR("Gordon Hollingworth");
+MODULE_AUTHOR("Nicolas Saenz Julienne <nsaenzjulienne@suse.de>");
+MODULE_DESCRIPTION("Raspberry Pi firmware based touchscreen driver");
+MODULE_LICENSE("GPL v2");