[PATCH 05/18] lirc driver for i2c-based IR receivers
From: Jarod Wilson
Date: Tue Sep 09 2008 - 00:08:20 EST
Successfully tested with the IR interface on a Hauppauge PVR-250 and
the flimsly little grey remote that shipped with it.
Signed-off-by: Jarod Wilson <jarod@xxxxxxxxxx>
Signed-off-by: Janne Grunau <j@xxxxxxxxxx>
CC: Christoph Bartelmus <lirc@xxxxxxxxxxxx>
Tested-by: Jarod Wilson <jarod@xxxxxxxxxx>
---
drivers/input/lirc/Kconfig | 8 +
drivers/input/lirc/Makefile | 1 +
drivers/input/lirc/lirc_i2c.c | 639 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 648 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/lirc/lirc_i2c.c
diff --git a/drivers/input/lirc/Kconfig b/drivers/input/lirc/Kconfig
index 0a0b059..ba30d2e 100644
--- a/drivers/input/lirc/Kconfig
+++ b/drivers/input/lirc/Kconfig
@@ -18,6 +18,14 @@ config LIRC_DEV
help
LIRC device loadable module support, required for most LIRC drivers
+config LIRC_I2C
+ tristate "I2C Based IR Receivers"
+ default n
+ depends on LIRC_DEV
+ help
+ Driver for I2C-based IR receivers, such as those commonly
+ found onboard Hauppauge PVR-150/250/350 video capture cards
+
config LIRC_MCEUSB
tristate "Microsoft Media Center Ed. Receiver, v1"
default n
diff --git a/drivers/input/lirc/Makefile b/drivers/input/lirc/Makefile
index f6accb9..99765d9 100644
--- a/drivers/input/lirc/Makefile
+++ b/drivers/input/lirc/Makefile
@@ -6,6 +6,7 @@
EXTRA_CFLAGS =-DIRCTL_DEV_MAJOR=61 -DLIRC_SERIAL_TRANSMITTER -I$(src)
obj-$(CONFIG_LIRC_DEV) += lirc_dev.o
+obj-$(CONFIG_LIRC_I2C) += lirc_i2c.o
obj-$(CONFIG_LIRC_MCEUSB) += lirc_mceusb.o
obj-$(CONFIG_LIRC_MCEUSB2) += lirc_mceusb2.o
obj-$(CONFIG_LIRC_SERIAL) += lirc_serial.o
diff --git a/drivers/input/lirc/lirc_i2c.c b/drivers/input/lirc/lirc_i2c.c
new file mode 100644
index 0000000..4714641
--- /dev/null
+++ b/drivers/input/lirc/lirc_i2c.c
@@ -0,0 +1,639 @@
+/*
+ * i2c IR lirc plugin for Hauppauge and Pixelview cards - new 2.3.x i2c stack
+ *
+ * Copyright (c) 2000 Gerd Knorr <kraxel@xxxxxxxxxxxxxxxxxxxxx>
+ * modified for PixelView (BT878P+W/FM) by
+ * Michal Kochanowicz <mkochano@xxxxxxxxxx>
+ * Christoph Bartelmus <lirc@xxxxxxxxxxxx>
+ * modified for KNC ONE TV Station/Anubis Typhoon TView Tuner by
+ * Ulrich Mueller <ulrich.mueller42@xxxxxx>
+ * modified for Asus TV-Box and Creative/VisionTek BreakOut-Box by
+ * Stefan Jahn <stefan@xxxxxxxx>
+ * modified for inclusion into kernel sources by
+ * Jerome Brock <jbrock@xxxxxxxxxxxxxxxxxxxxx>
+ * modified for Leadtek Winfast PVR2000 by
+ * Thomas Reitmayr (treitmayr@xxxxxxxxx)
+ * modified for Hauppauge HVR-1300 by
+ * Jan Frey (jfrey@xxxxxx)
+ *
+ * parts are cut&pasted from the old lirc_haup.c driver
+ *
+ * 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/version.h>
+#include <linux/module.h>
+#include <linux/kmod.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <linux/timer.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+
+#include <linux/semaphore.h>
+
+#include "lirc_dev.h"
+
+struct IR {
+ struct lirc_plugin l;
+ struct i2c_client c;
+ int nextkey;
+ unsigned char b[3];
+ unsigned char bits;
+ unsigned char flag;
+};
+
+/* ----------------------------------------------------------------------- */
+
+#define DEVICE_NAME "lirc_i2c"
+
+/* ----------------------------------------------------------------------- */
+/* insmod parameters */
+
+static int debug; /* debug output */
+static int minor = -1; /* minor number */
+
+#define dprintk(fmt, args...) \
+ do { \
+ if (debug) \
+ printk(KERN_DEBUG DEVICE_NAME ": " fmt, \
+ ## args); \
+ } while (0)
+
+/* ----------------------------------------------------------------------- */
+
+static inline int reverse(int data, int bits)
+{
+ int i;
+ int c;
+
+ for (c = 0, i = 0; i < bits; i++)
+ c |= ((data & (1<<i)) ? 1 : 0) << (bits-1-i);
+
+ return c;
+}
+
+static int add_to_buf_adap(void *data, struct lirc_buffer *buf)
+{
+ struct IR *ir = data;
+ unsigned char keybuf[4];
+
+ keybuf[0] = 0x00;
+ i2c_master_send(&ir->c, keybuf, 1);
+ /* poll IR chip */
+ if (i2c_master_recv(&ir->c, keybuf, sizeof(keybuf)) != sizeof(keybuf)) {
+ dprintk("read error\n");
+ return -EIO;
+ }
+
+ dprintk("key (0x%02x%02x%02x%02x)\n",
+ keybuf[0], keybuf[1], keybuf[2], keybuf[3]);
+
+ /* key pressed ? */
+ if (keybuf[2] == 0xff)
+ return -ENODATA;
+
+ /* remove repeat bit */
+ keybuf[2] &= 0x7f;
+ keybuf[3] |= 0x80;
+
+ lirc_buffer_write_1(buf, keybuf);
+ return 0;
+}
+
+static int add_to_buf_pcf8574(void *data, struct lirc_buffer *buf)
+{
+ struct IR *ir = data;
+ int rc;
+ unsigned char all, mask;
+ unsigned char key;
+
+ /* compute all valid bits (key code + pressed/release flag) */
+ all = ir->bits | ir->flag;
+
+ /* save IR writable mask bits */
+ mask = i2c_smbus_read_byte(&ir->c) & ~all;
+
+ /* send bit mask */
+ rc = i2c_smbus_write_byte(&ir->c, (0xff & all) | mask);
+
+ /* receive scan code */
+ rc = i2c_smbus_read_byte(&ir->c);
+
+ if (rc == -1) {
+ dprintk("%s read error\n", ir->c.name);
+ return -EIO;
+ }
+
+ /* drop duplicate polls */
+ if (ir->b[0] == (rc & all))
+ return -ENODATA;
+
+ ir->b[0] = rc & all;
+
+ dprintk("%s key 0x%02X %s\n", ir->c.name, rc & ir->bits,
+ (rc & ir->flag) ? "released" : "pressed");
+
+ if (rc & ir->flag) {
+ /* ignore released buttons */
+ return -ENODATA;
+ }
+
+ /* set valid key code */
+ key = rc & ir->bits;
+ lirc_buffer_write_1(buf, &key);
+ return 0;
+}
+
+/* common for Hauppauge IR receivers */
+static int add_to_buf_haup_common(void *data, struct lirc_buffer *buf,
+ unsigned char *keybuf, int size, int offset)
+{
+ struct IR *ir = data;
+ __u16 code;
+ unsigned char codes[2];
+
+ /* poll IR chip */
+ if (size == i2c_master_recv(&ir->c, keybuf, size)) {
+ ir->b[0] = keybuf[offset];
+ ir->b[1] = keybuf[offset+1];
+ ir->b[2] = keybuf[offset+2];
+ dprintk("key (0x%02x/0x%02x)\n", ir->b[0], ir->b[1]);
+ } else {
+ dprintk("read error\n");
+ /* keep last successfull read buffer */
+ }
+
+ /* key pressed ? */
+ if ((ir->b[0] & 0x80) == 0)
+ return -ENODATA;
+
+ /* look what we have */
+ code = (((__u16)ir->b[0]&0x7f)<<6) | (ir->b[1]>>2);
+
+ codes[0] = (code >> 8) & 0xff;
+ codes[1] = code & 0xff;
+
+ /* return it */
+ lirc_buffer_write_1(buf, codes);
+ return 0;
+}
+
+/* specific for the Hauppauge PVR150 IR receiver */
+static int add_to_buf_haup_pvr150(void *data, struct lirc_buffer *buf)
+{
+ unsigned char keybuf[6];
+ /* fetch 6 bytes, first relevant is at offset 3 */
+ return add_to_buf_haup_common(data, buf, keybuf, 6, 3);
+}
+
+/* used for all Hauppauge IR receivers but the PVR150 */
+static int add_to_buf_haup(void *data, struct lirc_buffer *buf)
+{
+ unsigned char keybuf[3];
+ /* fetch 3 bytes, first relevant is at offset 0 */
+ return add_to_buf_haup_common(data, buf, keybuf, 3, 0);
+}
+
+
+static int add_to_buf_pvr2000(void *data, struct lirc_buffer *buf)
+{
+ struct IR *ir = data;
+ unsigned char key;
+ s32 flags;
+ s32 code;
+
+ /* poll IR chip */
+ flags = i2c_smbus_read_byte_data(&ir->c, 0x10);
+ if (-1 == flags) {
+ dprintk("read error\n");
+ return -ENODATA;
+ }
+ /* key pressed ? */
+ if (0 == (flags & 0x80))
+ return -ENODATA;
+
+ /* read actual key code */
+ code = i2c_smbus_read_byte_data(&ir->c, 0x00);
+ if (-1 == code) {
+ dprintk("read error\n");
+ return -ENODATA;
+ }
+
+ key = code & 0xFF;
+
+ dprintk("IR Key/Flags: (0x%02x/0x%02x)\n", key, flags & 0xFF);
+
+ /* return it */
+ lirc_buffer_write_1(buf, &key);
+ return 0;
+}
+
+static int add_to_buf_pixelview(void *data, struct lirc_buffer *buf)
+{
+ struct IR *ir = data;
+ unsigned char key;
+
+ /* poll IR chip */
+ if (1 != i2c_master_recv(&ir->c, &key, 1)) {
+ dprintk("read error\n");
+ return -1;
+ }
+ dprintk("key %02x\n", key);
+
+ /* return it */
+ lirc_buffer_write_1(buf, &key);
+ return 0;
+}
+
+static int add_to_buf_pv951(void *data, struct lirc_buffer *buf)
+{
+ struct IR *ir = data;
+ unsigned char key;
+ unsigned char codes[4];
+
+ /* poll IR chip */
+ if (1 != i2c_master_recv(&ir->c, &key, 1)) {
+ dprintk("read error\n");
+ return -ENODATA;
+ }
+ /* ignore 0xaa */
+ if (key == 0xaa)
+ return -ENODATA;
+ dprintk("key %02x\n", key);
+
+ codes[0] = 0x61;
+ codes[1] = 0xD6;
+ codes[2] = reverse(key, 8);
+ codes[3] = (~codes[2])&0xff;
+
+ lirc_buffer_write_1(buf, codes);
+ return 0;
+}
+
+static int add_to_buf_knc1(void *data, struct lirc_buffer *buf)
+{
+ static unsigned char last_key = 0xFF;
+ struct IR *ir = data;
+ unsigned char key;
+
+ /* poll IR chip */
+ if (1 != i2c_master_recv(&ir->c, &key, 1)) {
+ dprintk("read error\n");
+ return -ENODATA;
+ }
+
+ /* it seems that 0xFE indicates that a button is still hold
+ down, while 0xFF indicates that no button is hold
+ down. 0xFE sequences are sometimes interrupted by 0xFF */
+
+ dprintk("key %02x\n", key);
+
+ if (key == 0xFF)
+ return -ENODATA;
+
+ if (key == 0xFE)
+ key = last_key;
+
+ last_key = key;
+ lirc_buffer_write_1(buf, &key);
+
+ return 0;
+}
+
+static int set_use_inc(void *data)
+{
+ struct IR *ir = data;
+
+ /* lock bttv in memory while /dev/lirc is in use */
+ i2c_use_client(&ir->c);
+
+ return 0;
+}
+
+static void set_use_dec(void *data)
+{
+ struct IR *ir = data;
+
+ i2c_release_client(&ir->c);
+}
+
+static struct lirc_plugin lirc_template = {
+ .name = "lirc_i2c",
+ .set_use_inc = set_use_inc,
+ .set_use_dec = set_use_dec,
+ .dev = NULL,
+ .owner = THIS_MODULE,
+};
+
+/* ----------------------------------------------------------------------- */
+
+static int ir_attach(struct i2c_adapter *adap, int addr,
+ unsigned short flags, int kind);
+static int ir_detach(struct i2c_client *client);
+static int ir_probe(struct i2c_adapter *adap);
+static int ir_command(struct i2c_client *client, unsigned int cmd, void *arg);
+
+static struct i2c_driver driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "i2c ir driver",
+ },
+ .attach_adapter = ir_probe,
+ .detach_client = ir_detach,
+ .command = ir_command,
+};
+
+static struct i2c_client client_template = {
+ .name = "unset",
+ .driver = &driver
+};
+
+static int ir_attach(struct i2c_adapter *adap, int addr,
+ unsigned short flags, int kind)
+{
+ struct IR *ir;
+ int err;
+
+ client_template.adapter = adap;
+ client_template.addr = addr;
+
+ ir = kmalloc(sizeof(struct IR), GFP_KERNEL);
+ if (!ir)
+ return -ENOMEM;
+ memcpy(&ir->l, &lirc_template, sizeof(struct lirc_plugin));
+ memcpy(&ir->c, &client_template, sizeof(struct i2c_client));
+
+ ir->c.adapter = adap;
+ ir->c.addr = addr;
+ i2c_set_clientdata(&ir->c, ir);
+ ir->l.data = ir;
+ ir->l.minor = minor;
+ ir->l.sample_rate = 10;
+ ir->nextkey = -1;
+
+ switch (addr) {
+ case 0x64:
+ strlcpy(ir->c.name, "Pixelview IR", I2C_NAME_SIZE);
+ ir->l.code_length = 8;
+ ir->l.add_to_buf = add_to_buf_pixelview;
+ break;
+ case 0x4b:
+ strlcpy(ir->c.name, "PV951 IR", I2C_NAME_SIZE);
+ ir->l.code_length = 32;
+ ir->l.add_to_buf = add_to_buf_pv951;
+ break;
+ case 0x71:
+ if (adap->id == I2C_HW_B_BT848 ||
+ adap->id == I2C_HW_B_CX2341X) {
+ /* The PVR150 IR receiver uses the same protocol as
+ * other Hauppauge cards, but the data flow is
+ * different, so we need to deal with it by its own. */
+ strlcpy(ir->c.name, "Hauppauge PVR150", I2C_NAME_SIZE);
+ } else /* I2C_HW_B_CX2388x */
+ strlcpy(ir->c.name, "Hauppauge HVR1300", I2C_NAME_SIZE);
+ ir->l.code_length = 13;
+ ir->l.add_to_buf = add_to_buf_haup_pvr150;
+ break;
+ case 0x6b:
+ strlcpy(ir->c.name, "Adaptec IR", I2C_NAME_SIZE);
+ ir->l.code_length = 32;
+ ir->l.add_to_buf = add_to_buf_adap;
+ break;
+ case 0x18:
+ case 0x1a:
+ if (adap->id == I2C_HW_B_BT848 ||
+ adap->id == I2C_HW_B_CX2341X) {
+ strlcpy(ir->c.name, "Hauppauge IR", I2C_NAME_SIZE);
+ ir->l.code_length = 13;
+ ir->l.add_to_buf = add_to_buf_haup;
+ } else { /* I2C_HW_B_CX2388x */
+ strlcpy(ir->c.name, "Leadtek IR", I2C_NAME_SIZE);
+ ir->l.code_length = 8;
+ ir->l.add_to_buf = add_to_buf_pvr2000;
+ }
+ break;
+ case 0x30:
+ strlcpy(ir->c.name, "KNC ONE IR", I2C_NAME_SIZE);
+ ir->l.code_length = 8;
+ ir->l.add_to_buf = add_to_buf_knc1;
+ break;
+ case 0x21:
+ case 0x23:
+ strlcpy(ir->c.name, "TV-Box IR", I2C_NAME_SIZE);
+ ir->l.code_length = 8;
+ ir->l.add_to_buf = add_to_buf_pcf8574;
+ ir->bits = flags & 0xff;
+ ir->flag = (flags >> 8) & 0xff;
+ break;
+ default:
+ /* shouldn't happen */
+ printk("lirc_i2c: Huh? unknown i2c address (0x%02x)?\n", addr);
+ kfree(ir);
+ return -1;
+ }
+ printk(KERN_INFO "lirc_i2c: chip 0x%x found @ 0x%02x (%s)\n",
+ adap->id, addr, ir->c.name);
+
+ /* register device */
+ err = i2c_attach_client(&ir->c);
+ if (err) {
+ kfree(ir);
+ return err;
+ }
+ ir->l.minor = lirc_register_plugin(&ir->l);
+
+ return 0;
+}
+
+static int ir_detach(struct i2c_client *client)
+{
+ struct IR *ir = i2c_get_clientdata(client);
+
+ /* unregister device */
+ lirc_unregister_plugin(ir->l.minor);
+ i2c_detach_client(&ir->c);
+
+ /* free memory */
+ kfree(ir);
+ return 0;
+}
+
+static int ir_probe(struct i2c_adapter *adap)
+{
+ /* The external IR receiver is at i2c address 0x34 (0x35 for
+ * reads). Future Hauppauge cards will have an internal
+ * receiver at 0x30 (0x31 for reads). In theory, both can be
+ * fitted, and Hauppauge suggest an external overrides an
+ * internal.
+ *
+ * That's why we probe 0x1a (~0x34) first. CB
+ *
+ * The i2c address for the Hauppauge PVR-150 card is 0xe2,
+ * so we need to probe 0x71 as well. */
+
+ static const int probe[] = {
+ 0x1a, /* Hauppauge IR external */
+ 0x18, /* Hauppauge IR internal */
+ 0x71, /* Hauppauge IR (PVR150) */
+ 0x4b, /* PV951 IR */
+ 0x64, /* Pixelview IR */
+ 0x30, /* KNC ONE IR */
+ 0x6b, /* Adaptec IR */
+ -1};
+
+ static const int probe_cx88[] = {
+ 0x18, /* Leadtek Winfast PVR2000 */
+ 0x71, /* Hauppauge HVR-IR */
+ -1};
+
+ struct i2c_client c;
+ char buf;
+ int i, rc;
+
+ if (adap->id == I2C_HW_B_BT848 ||
+ adap->id == I2C_HW_B_CX2341X) {
+ memset(&c, 0, sizeof(c));
+ c.adapter = adap;
+ for (i = 0; -1 != probe[i]; i++) {
+ c.addr = probe[i];
+ rc = i2c_master_recv(&c, &buf, 1);
+ dprintk("probe 0x%02x @ %s: %s\n",
+ probe[i], adap->name,
+ (1 == rc) ? "yes" : "no");
+ if (1 == rc)
+ ir_attach(adap, probe[i], 0, 0);
+ }
+ }
+
+ /* Leadtek Winfast PVR2000 or Hauppauge HVR-1300 */
+ else if (adap->id == I2C_HW_B_CX2388x) {
+ memset(&c, 0, sizeof(c));
+ c.adapter = adap;
+ for (i = 0; -1 != probe_cx88[i]; i++) {
+ c.addr = probe_cx88[i];
+ rc = i2c_master_recv(&c, &buf, 1);
+ dprintk("probe 0x%02x @ %s: %s\n",
+ c.addr, adap->name,
+ (1 == rc) ? "yes" : "no");
+ if (1 == rc)
+ ir_attach(adap, c.addr, 0, 0);
+ }
+ }
+
+ /* Asus TV-Box and Creative/VisionTek BreakOut-Box (PCF8574) */
+ else if (adap->id == I2C_HW_B_RIVA) {
+ /* addresses to probe;
+ leave 0x24 and 0x25 because SAA7113H possibly uses it
+ 0x21 and 0x22 possibly used by SAA7108E
+ Asus: 0x21 is a correct address (channel 1 of PCF8574)
+ Creative: 0x23 is a correct address (channel 3 of PCF8574)
+ VisionTek: 0x23 is a correct address (channel 3 of PCF8574)
+ */
+ static const int pcf_probe[] = { 0x20, 0x21, 0x22, 0x23,
+ 0x24, 0x25, 0x26, 0x27, -1 };
+ int ret1, ret2, ret3, ret4;
+ unsigned char bits = 0, flag = 0;
+
+ memset(&c, 0, sizeof(c));
+ c.adapter = adap;
+ for (i = 0; -1 != pcf_probe[i]; i++) {
+ c.addr = pcf_probe[i];
+ ret1 = i2c_smbus_write_byte(&c, 0xff);
+ ret2 = i2c_smbus_read_byte(&c);
+ ret3 = i2c_smbus_write_byte(&c, 0x00);
+ ret4 = i2c_smbus_read_byte(&c);
+
+ /* ensure that the writable bitmask works correctly */
+ rc = 0;
+ if (ret1 != -1 && ret2 != -1 &&
+ ret3 != -1 && ret4 != -1) {
+ /* in the Asus TV-Box: bit 1-0 */
+ if (((ret2 & 0x03) == 0x03) &&
+ ((ret4 & 0x03) == 0x00)) {
+ bits = (unsigned char) ~0x07;
+ flag = 0x04;
+ rc = 1;
+ }
+ /* in the Creative/VisionTek BreakOut-Box: bit 7-6 */
+ if (((ret2 & 0xc0) == 0xc0) &&
+ ((ret4 & 0xc0) == 0x00)) {
+ bits = (unsigned char) ~0xe0;
+ flag = 0x20;
+ rc = 1;
+ }
+ }
+ dprintk("probe 0x%02x @ %s: %s\n",
+ c.addr, adap->name, rc ? "yes" : "no");
+ if (rc)
+ ir_attach(adap, pcf_probe[i],
+ bits|(flag<<8), 0);
+ }
+ }
+
+ return 0;
+}
+
+static int ir_command(struct i2c_client *client, unsigned int cmd, void *arg)
+{
+ /* nothing */
+ return 0;
+}
+
+/* ----------------------------------------------------------------------- */
+#ifdef MODULE
+
+int init_module(void)
+{
+ request_module("bttv");
+ request_module("rivatv");
+ request_module("ivtv");
+ request_module("cx8800");
+ i2c_add_driver(&driver);
+ return 0;
+}
+
+void cleanup_module(void)
+{
+ i2c_del_driver(&driver);
+}
+
+MODULE_DESCRIPTION("Infrared receiver driver for Hauppauge and "
+ "Pixelview cards (i2c stack)");
+MODULE_AUTHOR("Gerd Knorr, Michal Kochanowicz, Christoph Bartelmus, "
+ "Ulrich Mueller, Stefan Jahn, Jerome Brock");
+MODULE_LICENSE("GPL");
+
+module_param(minor, int, 0444);
+MODULE_PARM_DESC(minor, "Preferred minor device number");
+
+module_param(debug, bool, 0644);
+MODULE_PARM_DESC(debug, "Enable debugging messages");
+
+#endif /* MODULE */
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-basic-offset: 8
+ * End:
+ */
--
1.6.0.1
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