[media] rc: Add support for the TechnoTrend USB IR Receiver

This driver adds support for TechnoTrend USB IR Receiver. It is a complete
rewrite of the staging/media/lirc/lirc_ttusbir driver. It adds more
accurate sample reporting and led control.

Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 400 insertions, 0 deletions

diff --git a/drivers/media/rc/ttusbir.c b/drivers/media/rc/ttusbir.c
new file mode 100644
index 000000000000..71f03acabac8
--- /dev/null
+++ b/drivers/media/rc/ttusbir.c
@@ -0,0 +1,400 @@
+/*
+ * TechnoTrend USB IR Receiver
+ *
+ * Copyright (C) 2012 Sean Young <sean@mess.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/usb/input.h>
+#include <linux/slab.h>
+#include <linux/leds.h>
+#include <media/rc-core.h>
+
+#define DRIVER_NAME	"ttusbir"
+#define DRIVER_DESC	"TechnoTrend USB IR Receiver"
+/*
+ * The Windows driver uses 8 URBS, the original lirc drivers has a
+ * configurable amount (2 default, 4 max). This device generates about 125
+ * messages per second (!), whether IR is idle or not.
+ */
+#define NUM_URBS	4
+#define NS_PER_BYTE	62500
+#define NS_PER_BIT	(NS_PER_BYTE/8)
+
+struct ttusbir {
+	struct rc_dev *rc;
+	struct device *dev;
+	struct usb_device *udev;
+
+	struct urb *urb[NUM_URBS];
+
+	struct led_classdev led;
+	struct urb *bulk_urb;
+	uint8_t bulk_buffer[5];
+	int bulk_out_endp, iso_in_endp;
+	bool led_on, is_led_on;
+	atomic_t led_complete;
+
+	char phys[64];
+};
+
+static enum led_brightness ttusbir_brightness_get(struct led_classdev *led_dev)
+{
+	struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
+
+	return tt->led_on ? LED_FULL : LED_OFF;
+}
+
+static void ttusbir_set_led(struct ttusbir *tt)
+{
+	int ret;
+
+	smp_mb();
+
+	if (tt->led_on != tt->is_led_on &&
+				atomic_add_unless(&tt->led_complete, 1, 1)) {
+		tt->bulk_buffer[4] = tt->is_led_on = tt->led_on;
+		ret = usb_submit_urb(tt->bulk_urb, GFP_ATOMIC);
+		if (ret && ret != -ENODEV) {
+			dev_warn(tt->dev, "failed to submit bulk urb: %d\n",
+									ret);
+			atomic_dec(&tt->led_complete);
+		}
+	}
+}
+
+static void ttusbir_brightness_set(struct led_classdev *led_dev, enum
+						led_brightness brightness)
+{
+	struct ttusbir *tt = container_of(led_dev, struct ttusbir, led);
+
+	tt->led_on = brightness != LED_OFF;
+
+	ttusbir_set_led(tt);
+}
+
+/*
+ * The urb cannot be reused until the urb completes
+ */
+static void ttusbir_bulk_complete(struct urb *urb)
+{
+	struct ttusbir *tt = urb->context;
+
+	atomic_dec(&tt->led_complete);
+
+	switch (urb->status) {
+	case 0:
+		break;
+	case -ECONNRESET:
+	case -ENOENT:
+	case -ESHUTDOWN:
+		usb_unlink_urb(urb);
+		return;
+	case -EPIPE:
+	default:
+		dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
+		break;
+	}
+
+	ttusbir_set_led(tt);
+}
+
+/*
+ * The data is one bit per sample, a set bit signifying silence and samples
+ * being MSB first. Bit 0 can contain garbage so take it to be whatever
+ * bit 1 is, so we don't have unexpected edges.
+ */
+static void ttusbir_process_ir_data(struct ttusbir *tt, uint8_t *buf)
+{
+	unsigned i, v, b;
+	DEFINE_IR_RAW_EVENT(rawir);
+
+	init_ir_raw_event(&rawir);
+
+	for (i = 0; i < 128; i++) {
+		v = buf[i] & 0xfe;
+		switch (v) {
+		case 0xfe:
+			rawir.pulse = false;
+			rawir.duration = NS_PER_BYTE;
+			ir_raw_event_store_with_filter(tt->rc, &rawir);
+			break;
+		case 0:
+			rawir.pulse = true;
+			rawir.duration = NS_PER_BYTE;
+			ir_raw_event_store_with_filter(tt->rc, &rawir);
+			break;
+		default:
+			/* one edge per byte */
+			if (v & 2) {
+				b = ffz(v | 1);
+				rawir.pulse = true;
+			} else {
+				b = ffs(v) - 1;
+				rawir.pulse = false;
+			}
+
+			rawir.duration = NS_PER_BIT * (8 - b);
+			ir_raw_event_store_with_filter(tt->rc, &rawir);
+
+			rawir.pulse = !rawir.pulse;
+			rawir.duration = NS_PER_BIT * b;
+			ir_raw_event_store_with_filter(tt->rc, &rawir);
+			break;
+		}
+	}
+
+	ir_raw_event_handle(tt->rc);
+}
+
+static void ttusbir_urb_complete(struct urb *urb)
+{
+	struct ttusbir *tt = urb->context;
+	int rc;
+
+	switch (urb->status) {
+	case 0:
+		ttusbir_process_ir_data(tt, urb->transfer_buffer);
+		break;
+	case -ECONNRESET:
+	case -ENOENT:
+	case -ESHUTDOWN:
+		usb_unlink_urb(urb);
+		return;
+	case -EPIPE:
+	default:
+		dev_dbg(tt->dev, "Error: urb status = %d\n", urb->status);
+		break;
+	}
+
+	rc = usb_submit_urb(urb, GFP_ATOMIC);
+	if (rc && rc != -ENODEV)
+		dev_warn(tt->dev, "failed to resubmit urb: %d\n", rc);
+}
+
+static int __devinit ttusbir_probe(struct usb_interface *intf,
+						const struct usb_device_id *id)
+{
+	struct ttusbir *tt;
+	struct usb_interface_descriptor *idesc;
+	struct usb_endpoint_descriptor *desc;
+	struct rc_dev *rc;
+	int i, j, ret;
+	int altsetting = -1;
+
+	tt = kzalloc(sizeof(*tt), GFP_KERNEL);
+	rc = rc_allocate_device();
+	if (!tt || !rc) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	/* find the correct alt setting */
+	for (i = 0; i < intf->num_altsetting && altsetting == -1; i++) {
+		int bulk_out_endp = -1, iso_in_endp = -1;
+
+		idesc = &intf->altsetting[i].desc;
+
+		for (j = 0; j < idesc->bNumEndpoints; j++) {
+			desc = &intf->altsetting[i].endpoint[j].desc;
+			if (usb_endpoint_dir_in(desc) &&
+					usb_endpoint_xfer_isoc(desc) &&
+					desc->wMaxPacketSize == 0x10)
+				iso_in_endp = j;
+			else if (usb_endpoint_dir_out(desc) &&
+					usb_endpoint_xfer_bulk(desc) &&
+					desc->wMaxPacketSize == 0x20)
+				bulk_out_endp = j;
+
+			if (bulk_out_endp != -1 && iso_in_endp != -1) {
+				tt->bulk_out_endp = bulk_out_endp;
+				tt->iso_in_endp = iso_in_endp;
+				altsetting = i;
+				break;
+			}
+		}
+	}
+
+	if (altsetting == -1) {
+		dev_err(&intf->dev, "cannot find expected altsetting\n");
+		ret = -ENODEV;
+		goto out;
+	}
+
+	tt->dev = &intf->dev;
+	tt->udev = interface_to_usbdev(intf);
+	tt->rc = rc;
+
+	ret = usb_set_interface(tt->udev, 0, altsetting);
+	if (ret)
+		goto out;
+
+	for (i = 0; i < NUM_URBS; i++) {
+		struct urb *urb = usb_alloc_urb(8, GFP_KERNEL);
+		void *buffer;
+
+		if (!urb) {
+			ret = -ENOMEM;
+			goto out;
+		}
+
+		urb->dev = tt->udev;
+		urb->context = tt;
+		urb->pipe = usb_rcvisocpipe(tt->udev, tt->iso_in_endp);
+		urb->interval = 1;
+		buffer = usb_alloc_coherent(tt->udev, 128, GFP_KERNEL,
+						&urb->transfer_dma);
+		if (!buffer) {
+			usb_free_urb(urb);
+			ret = -ENOMEM;
+			goto out;
+		}
+		urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP | URB_ISO_ASAP;
+		urb->transfer_buffer = buffer;
+		urb->complete = ttusbir_urb_complete;
+		urb->number_of_packets = 8;
+		urb->transfer_buffer_length = 128;
+
+		for (j = 0; j < 8; j++) {
+			urb->iso_frame_desc[j].offset = j * 16;
+			urb->iso_frame_desc[j].length = 16;
+		}
+
+		tt->urb[i] = urb;
+	}
+
+	tt->bulk_urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!tt->bulk_urb) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	tt->bulk_buffer[0] = 0xaa;
+	tt->bulk_buffer[1] = 0x01;
+	tt->bulk_buffer[2] = 0x05;
+	tt->bulk_buffer[3] = 0x01;
+
+	usb_fill_bulk_urb(tt->bulk_urb, tt->udev, usb_sndbulkpipe(tt->udev,
+		tt->bulk_out_endp), tt->bulk_buffer, sizeof(tt->bulk_buffer),
+						ttusbir_bulk_complete, tt);
+
+	tt->led.name = "ttusbir:yellow:power";
+	tt->led.brightness_set = ttusbir_brightness_set;
+	tt->led.brightness_get = ttusbir_brightness_get;
+	tt->is_led_on = tt->led_on = true;
+	atomic_set(&tt->led_complete, 0);
+	ret = led_classdev_register(&intf->dev, &tt->led);
+	if (ret)
+		goto out;
+
+	usb_make_path(tt->udev, tt->phys, sizeof(tt->phys));
+
+	rc->input_name = DRIVER_DESC;
+	rc->input_phys = tt->phys;
+	usb_to_input_id(tt->udev, &rc->input_id);
+	rc->dev.parent = &intf->dev;
+	rc->driver_type = RC_DRIVER_IR_RAW;
+	rc->allowed_protos = RC_TYPE_ALL;
+	rc->priv = tt;
+	rc->driver_name = DRIVER_NAME;
+	rc->map_name = RC_MAP_TT_1500;
+	rc->timeout = MS_TO_NS(100);
+	/*
+	 * The precision is NS_PER_BIT, but since every 8th bit can be
+	 * overwritten with garbage the accuracy is at best 2 * NS_PER_BIT.
+	 */
+	rc->rx_resolution = NS_PER_BIT;
+
+	ret = rc_register_device(rc);
+	if (ret) {
+		dev_err(&intf->dev, "failed to register rc device %d\n", ret);
+		goto out2;
+	}
+
+	usb_set_intfdata(intf, tt);
+
+	for (i = 0; i < NUM_URBS; i++) {
+		ret = usb_submit_urb(tt->urb[i], GFP_KERNEL);
+		if (ret) {
+			dev_err(tt->dev, "failed to submit urb %d\n", ret);
+			goto out3;
+		}
+	}
+
+	return 0;
+out3:
+	rc_unregister_device(rc);
+out2:
+	led_classdev_unregister(&tt->led);
+out:
+	if (tt) {
+		for (i = 0; i < NUM_URBS && tt->urb[i]; i++) {
+			struct urb *urb = tt->urb[i];
+
+			usb_kill_urb(urb);
+			usb_free_coherent(tt->udev, 128, urb->transfer_buffer,
+							urb->transfer_dma);
+			usb_free_urb(urb);
+		}
+		usb_kill_urb(tt->bulk_urb);
+		usb_free_urb(tt->bulk_urb);
+		kfree(tt);
+	}
+	rc_free_device(rc);
+
+	return ret;
+}
+
+static void __devexit ttusbir_disconnect(struct usb_interface *intf)
+{
+	struct ttusbir *tt = usb_get_intfdata(intf);
+	int i;
+
+	rc_unregister_device(tt->rc);
+	led_classdev_unregister(&tt->led);
+	for (i = 0; i < NUM_URBS; i++) {
+		usb_kill_urb(tt->urb[i]);
+		usb_free_coherent(tt->udev, 128, tt->urb[i]->transfer_buffer,
+						tt->urb[i]->transfer_dma);
+		usb_free_urb(tt->urb[i]);
+	}
+	usb_kill_urb(tt->bulk_urb);
+	usb_free_urb(tt->bulk_urb);
+	usb_set_intfdata(intf, NULL);
+	kfree(tt);
+}
+
+static const struct usb_device_id ttusbir_table[] = {
+	{ USB_DEVICE(0x0b48, 0x2003) },
+	{ }
+};
+
+static struct usb_driver ttusbir_driver = {
+	.name = DRIVER_NAME,
+	.id_table = ttusbir_table,
+	.probe = ttusbir_probe,
+	.disconnect = __devexit_p(ttusbir_disconnect)
+};
+
+module_usb_driver(ttusbir_driver);
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("Sean Young <sean@mess.org>");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(usb, ttusbir_table);
+