1 // SPDX-License-Identifier: GPL-2.0
3  * Raspberry Pi firmware based touchscreen driver
15 #include <linux/dma-mapping.h>
19 #include <linux/input/touchscreen.h>
20 #include <soc/bcm2835/raspberrypi-firmware.h>
70 	memcpy_fromio(&regs, ts->fw_regs_va, sizeof(regs));  in rpi_ts_poll()
72 	 * We poll the memory based register copy of the touchscreen chip using  in rpi_ts_poll()
73 	 * the number of points register to know whether the copy has been  in rpi_ts_poll()
75 	 * 0 - 10 points)  in rpi_ts_poll()
78 		 ts->fw_regs_va + offsetof(struct rpi_ts_regs, num_points));  in rpi_ts_poll()
81 	    (regs.num_points == 0 && ts->known_ids == 0))  in rpi_ts_poll()
96 			touchscreen_report_pos(input, &ts->prop, x, y, true);  in rpi_ts_poll()
100 	released_ids = ts->known_ids & ~modified_ids;  in rpi_ts_poll()
106 	ts->known_ids = modified_ids;  in rpi_ts_poll()
115 	struct device *dev = &ts->pdev->dev;  in rpi_ts_dma_cleanup()
117 	dma_free_coherent(dev, PAGE_SIZE, ts->fw_regs_va, ts->fw_regs_phys);  in rpi_ts_dma_cleanup()
122 	struct device *dev = &pdev->dev;  in rpi_ts_probe()
123 	struct device_node *np = dev->of_node;  in rpi_ts_probe()
134 		return -ENOENT;  in rpi_ts_probe()
137 	fw = devm_rpi_firmware_get(&pdev->dev, fw_node);  in rpi_ts_probe()
140 		return -EPROBE_DEFER;  in rpi_ts_probe()
144 		return -ENOMEM;  in rpi_ts_probe()
145 	ts->pdev = pdev;  in rpi_ts_probe()
147 	ts->fw_regs_va = dma_alloc_coherent(dev, PAGE_SIZE, &ts->fw_regs_phys,  in rpi_ts_probe()
149 	if (!ts->fw_regs_va) {  in rpi_ts_probe()
151 		return -ENOMEM;  in rpi_ts_probe()
160 	touchbuf = (u32)ts->fw_regs_phys;  in rpi_ts_probe()
171 		return -ENOMEM;  in rpi_ts_probe()
174 	ts->input = input;  in rpi_ts_probe()
177 	input->name = "raspberrypi-ts";  in rpi_ts_probe()
178 	input->id.bustype = BUS_HOST;  in rpi_ts_probe()
184 	touchscreen_parse_properties(input, true, &ts->prop);  in rpi_ts_probe()
211 	{ .compatible = "raspberrypi,firmware-ts", },
218 		.name = "raspberrypi-ts",
227 MODULE_DESCRIPTION("Raspberry Pi firmware based touchscreen driver");