HID based IPTS and ITHC support, 6.1 edition

drivers/hid/Kconfig

@@ -1290,4 +1290,8 @@ source "drivers/hid/amd-sfh-hid/Kconfig"
 
 source "drivers/hid/surface-hid/Kconfig"
 
+source "drivers/hid/ipts/Kconfig"
+
+source "drivers/hid/ithc/Kconfig"
+
 endmenu

drivers/hid/Makefile

@@ -164,3 +164,6 @@ obj-$(INTEL_ISH_FIRMWARE_DOWNLOADER)	+= intel-ish-hid/
 obj-$(CONFIG_AMD_SFH_HID)       += amd-sfh-hid/
 
 obj-$(CONFIG_SURFACE_HID_CORE)  += surface-hid/
+
+obj-$(CONFIG_HID_IPTS)          += ipts/
+obj-$(CONFIG_HID_ITHC)          += ithc/

drivers/misc/ipts/Kconfig → drivers/hid/ipts/Kconfig

@@ -1,8 +1,9 @@
 # SPDX-License-Identifier: GPL-2.0-or-later
 
-config MISC_IPTS
+config HID_IPTS
 	tristate "Intel Precise Touch & Stylus"
 	depends on INTEL_MEI
+	depends on HID
 	help
 	  Say Y here if your system has a touchscreen using Intels
 	  Precise Touch & Stylus (IPTS) technology.
@@ -11,7 +12,3 @@ config MISC_IPTS
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called ipts.
-
-	  Building this driver alone will not give you a working touchscreen.
-	  It only exposed a userspace API that can be used by a daemon to
-	  receive and process data from the touchscreen hardware.

drivers/misc/ipts/Makefile → drivers/hid/ipts/Makefile

@@ -3,10 +3,12 @@
 # Makefile for the IPTS touchscreen driver
 #
 
-obj-$(CONFIG_MISC_IPTS) += ipts.o
-ipts-objs := control.o
+obj-$(CONFIG_HID_IPTS) += ipts.o
+ipts-objs := cmd.o
+ipts-objs += control.o
+ipts-objs += hid.o
+ipts-objs += main.o
 ipts-objs += mei.o
 ipts-objs += receiver.o
 ipts-objs += resources.o
-ipts-objs += uapi.o
-
+ipts-objs += thread.o

drivers/hid/ipts/cmd.c

@@ -0,0 +1,62 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2016 Intel Corporation
+ * Copyright (c) 2020-2023 Dorian Stoll
+ *
+ * Linux driver for Intel Precise Touch & Stylus
+ */
+
+#include <linux/errno.h>
+#include <linux/types.h>
+
+#include "cmd.h"
+#include "context.h"
+#include "mei.h"
+#include "spec-device.h"
+
+int ipts_cmd_recv_timeout(struct ipts_context *ipts, enum ipts_command_code code,
+			  struct ipts_response *rsp, u64 timeout)
+{
+	int ret = 0;
+
+	if (!ipts)
+		return -EFAULT;
+
+	if (!rsp)
+		return -EFAULT;
+
+	/*
+	 * In a response, the command code will have the most significant bit flipped to 1.
+	 * If code is passed to ipts_mei_recv as is, no messages will be received.
+	 */
+	ret = ipts_mei_recv(&ipts->mei, code | IPTS_RSP_BIT, rsp, timeout);
+	if (ret < 0)
+		return ret;
+
+	dev_dbg(ipts->dev, "Received 0x%02X with status 0x%02X\n", code, rsp->status);
+
+	/*
+	 * Some devices will always return this error.
+	 * It is allowed to ignore it and to try continuing.
+	 */
+	if (rsp->status == IPTS_STATUS_COMPAT_CHECK_FAIL)
+		rsp->status = IPTS_STATUS_SUCCESS;
+
+	return 0;
+}
+
+int ipts_cmd_send(struct ipts_context *ipts, enum ipts_command_code code, void *data, size_t size)
+{
+	struct ipts_command cmd = { 0 };
+
+	if (!ipts)
+		return -EFAULT;
+
+	cmd.cmd = code;
+
+	if (data && size > 0)
+		memcpy(cmd.payload, data, size);
+
+	dev_dbg(ipts->dev, "Sending 0x%02X with %ld bytes payload\n", code, size);
+	return ipts_mei_send(&ipts->mei, &cmd, sizeof(cmd.cmd) + size);
+}

drivers/hid/ipts/cmd.h

@@ -0,0 +1,61 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2016 Intel Corporation
+ * Copyright (c) 2020-2023 Dorian Stoll
+ *
+ * Linux driver for Intel Precise Touch & Stylus
+ */
+
+#ifndef IPTS_CMD_H
+#define IPTS_CMD_H
+
+#include <linux/types.h>
+
+#include "context.h"
+#include "spec-device.h"
+
+/*
+ * The default timeout for receiving responses
+ */
+#define IPTS_CMD_DEFAULT_TIMEOUT 1000
+
+/*
+ * ipts_cmd_recv_timeout() - Receives a response to a command.
+ * @ipts: The IPTS driver context.
+ * @code: The type of the command / response.
+ * @rsp: The address that the received response will be copied to.
+ * @timeout: How many milliseconds the function will wait at most.
+ *
+ * A negative timeout means to wait forever.
+ *
+ * Returns: 0 on success, <0 on error, -EAGAIN if no response has been received.
+ */
+int ipts_cmd_recv_timeout(struct ipts_context *ipts, enum ipts_command_code code,
+			  struct ipts_response *rsp, u64 timeout);
+
+/*
+ * ipts_cmd_recv() - Receives a response to a command.
+ * @ipts: The IPTS driver context.
+ * @code: The type of the command / response.
+ * @rsp: The address that the received response will be copied to.
+ *
+ * Returns: 0 on success, <0 on error, -EAGAIN if no response has been received.
+ */
+static inline int ipts_cmd_recv(struct ipts_context *ipts, enum ipts_command_code code,
+				struct ipts_response *rsp)
+{
+	return ipts_cmd_recv_timeout(ipts, code, rsp, IPTS_CMD_DEFAULT_TIMEOUT);
+}
+
+/*
+ * ipts_cmd_send() - Executes a command on the device.
+ * @ipts: The IPTS driver context.
+ * @code: The type of the command to execute.
+ * @data: The payload containing parameters for the command.
+ * @size: The size of the payload.
+ *
+ * Returns: 0 on success, <0 on error.
+ */
+int ipts_cmd_send(struct ipts_context *ipts, enum ipts_command_code code, void *data, size_t size);
+
+#endif /* IPTS_CMD_H */

drivers/hid/ipts/context.h

@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (c) 2016 Intel Corporation
+ * Copyright (c) 2020-2023 Dorian Stoll
+ *
+ * Linux driver for Intel Precise Touch & Stylus
+ */
+
+#ifndef IPTS_CONTEXT_H
+#define IPTS_CONTEXT_H
+
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/hid.h>
+#include <linux/mei_cl_bus.h>
+#include <linux/mutex.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+
+#include "mei.h"
+#include "resources.h"
+#include "spec-device.h"
+#include "thread.h"
+
+struct ipts_context {
+	struct device *dev;
+	struct ipts_mei mei;
+
+	enum ipts_mode mode;
+
+	/*
+	 * Prevents concurrent GET_FEATURE reports.
+	 */
+	struct mutex feature_lock;
+	struct completion feature_event;
+
+	/*
+	 * These are not inside of struct ipts_resources
+	 * because they don't own the memory they point to.
+	 */
+	struct ipts_buffer feature_report;
+	struct ipts_buffer descriptor;
+
+	struct hid_device *hid;
+	struct ipts_device_info info;
+	struct ipts_resources resources;
+
+	struct ipts_thread receiver_loop;
+};
+
+#endif /* IPTS_CONTEXT_H */