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Diffstat (limited to 'drivers/media/pci/ivtv/ivtv-i2c.c')
-rw-r--r--drivers/media/pci/ivtv/ivtv-i2c.c760
1 files changed, 760 insertions, 0 deletions
diff --git a/drivers/media/pci/ivtv/ivtv-i2c.c b/drivers/media/pci/ivtv/ivtv-i2c.c
new file mode 100644
index 0000000..d47f41a
--- /dev/null
+++ b/drivers/media/pci/ivtv/ivtv-i2c.c
@@ -0,0 +1,760 @@
+/*
+ I2C functions
+ Copyright (C) 2003-2004 Kevin Thayer <nufan_wfk at yahoo.com>
+ Copyright (C) 2005-2007 Hans Verkuil <hverkuil@xs4all.nl>
+
+ 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
+ */
+
+/*
+ This file includes an i2c implementation that was reverse engineered
+ from the Hauppauge windows driver. Older ivtv versions used i2c-algo-bit,
+ which whilst fine under most circumstances, had trouble with the Zilog
+ CPU on the PVR-150 which handles IR functions (occasional inability to
+ communicate with the chip until it was reset) and also with the i2c
+ bus being completely unreachable when multiple PVR cards were present.
+
+ The implementation is very similar to i2c-algo-bit, but there are enough
+ subtle differences that the two are hard to merge. The general strategy
+ employed by i2c-algo-bit is to use udelay() to implement the timing
+ when putting out bits on the scl/sda lines. The general strategy taken
+ here is to poll the lines for state changes (see ivtv_waitscl and
+ ivtv_waitsda). In addition there are small delays at various locations
+ which poll the SCL line 5 times (ivtv_scldelay). I would guess that
+ since this is memory mapped I/O that the length of those delays is tied
+ to the PCI bus clock. There is some extra code to do with recovery
+ and retries. Since it is not known what causes the actual i2c problems
+ in the first place, the only goal if one was to attempt to use
+ i2c-algo-bit would be to try to make it follow the same code path.
+ This would be a lot of work, and I'm also not convinced that it would
+ provide a generic benefit to i2c-algo-bit. Therefore consider this
+ an engineering solution -- not pretty, but it works.
+
+ Some more general comments about what we are doing:
+
+ The i2c bus is a 2 wire serial bus, with clock (SCL) and data (SDA)
+ lines. To communicate on the bus (as a master, we don't act as a slave),
+ we first initiate a start condition (ivtv_start). We then write the
+ address of the device that we want to communicate with, along with a flag
+ that indicates whether this is a read or a write. The slave then issues
+ an ACK signal (ivtv_ack), which tells us that it is ready for reading /
+ writing. We then proceed with reading or writing (ivtv_read/ivtv_write),
+ and finally issue a stop condition (ivtv_stop) to make the bus available
+ to other masters.
+
+ There is an additional form of transaction where a write may be
+ immediately followed by a read. In this case, there is no intervening
+ stop condition. (Only the msp3400 chip uses this method of data transfer).
+ */
+
+#include "ivtv-driver.h"
+#include "ivtv-cards.h"
+#include "ivtv-gpio.h"
+#include "ivtv-i2c.h"
+#include <media/cx25840.h>
+
+/* i2c implementation for cx23415/6 chip, ivtv project.
+ * Author: Kevin Thayer (nufan_wfk at yahoo.com)
+ */
+/* i2c stuff */
+#define IVTV_REG_I2C_SETSCL_OFFSET 0x7000
+#define IVTV_REG_I2C_SETSDA_OFFSET 0x7004
+#define IVTV_REG_I2C_GETSCL_OFFSET 0x7008
+#define IVTV_REG_I2C_GETSDA_OFFSET 0x700c
+
+#define IVTV_CS53L32A_I2C_ADDR 0x11
+#define IVTV_M52790_I2C_ADDR 0x48
+#define IVTV_CX25840_I2C_ADDR 0x44
+#define IVTV_SAA7115_I2C_ADDR 0x21
+#define IVTV_SAA7127_I2C_ADDR 0x44
+#define IVTV_SAA717x_I2C_ADDR 0x21
+#define IVTV_MSP3400_I2C_ADDR 0x40
+#define IVTV_HAUPPAUGE_I2C_ADDR 0x50
+#define IVTV_WM8739_I2C_ADDR 0x1a
+#define IVTV_WM8775_I2C_ADDR 0x1b
+#define IVTV_TEA5767_I2C_ADDR 0x60
+#define IVTV_UPD64031A_I2C_ADDR 0x12
+#define IVTV_UPD64083_I2C_ADDR 0x5c
+#define IVTV_VP27SMPX_I2C_ADDR 0x5b
+#define IVTV_M52790_I2C_ADDR 0x48
+#define IVTV_AVERMEDIA_IR_RX_I2C_ADDR 0x40
+#define IVTV_HAUP_EXT_IR_RX_I2C_ADDR 0x1a
+#define IVTV_HAUP_INT_IR_RX_I2C_ADDR 0x18
+#define IVTV_Z8F0811_IR_TX_I2C_ADDR 0x70
+#define IVTV_Z8F0811_IR_RX_I2C_ADDR 0x71
+#define IVTV_ADAPTEC_IR_ADDR 0x6b
+
+/* This array should match the IVTV_HW_ defines */
+static const u8 hw_addrs[] = {
+ IVTV_CX25840_I2C_ADDR,
+ IVTV_SAA7115_I2C_ADDR,
+ IVTV_SAA7127_I2C_ADDR,
+ IVTV_MSP3400_I2C_ADDR,
+ 0,
+ IVTV_WM8775_I2C_ADDR,
+ IVTV_CS53L32A_I2C_ADDR,
+ 0,
+ IVTV_SAA7115_I2C_ADDR,
+ IVTV_UPD64031A_I2C_ADDR,
+ IVTV_UPD64083_I2C_ADDR,
+ IVTV_SAA717x_I2C_ADDR,
+ IVTV_WM8739_I2C_ADDR,
+ IVTV_VP27SMPX_I2C_ADDR,
+ IVTV_M52790_I2C_ADDR,
+ 0, /* IVTV_HW_GPIO dummy driver ID */
+ IVTV_AVERMEDIA_IR_RX_I2C_ADDR, /* IVTV_HW_I2C_IR_RX_AVER */
+ IVTV_HAUP_EXT_IR_RX_I2C_ADDR, /* IVTV_HW_I2C_IR_RX_HAUP_EXT */
+ IVTV_HAUP_INT_IR_RX_I2C_ADDR, /* IVTV_HW_I2C_IR_RX_HAUP_INT */
+ IVTV_Z8F0811_IR_TX_I2C_ADDR, /* IVTV_HW_Z8F0811_IR_TX_HAUP */
+ IVTV_Z8F0811_IR_RX_I2C_ADDR, /* IVTV_HW_Z8F0811_IR_RX_HAUP */
+ IVTV_ADAPTEC_IR_ADDR, /* IVTV_HW_I2C_IR_RX_ADAPTEC */
+};
+
+/* This array should match the IVTV_HW_ defines */
+static const char * const hw_devicenames[] = {
+ "cx25840",
+ "saa7115",
+ "saa7127_auto", /* saa7127 or saa7129 */
+ "msp3400",
+ "tuner",
+ "wm8775",
+ "cs53l32a",
+ "tveeprom",
+ "saa7114",
+ "upd64031a",
+ "upd64083",
+ "saa717x",
+ "wm8739",
+ "vp27smpx",
+ "m52790",
+ "gpio",
+ "ir_video", /* IVTV_HW_I2C_IR_RX_AVER */
+ "ir_video", /* IVTV_HW_I2C_IR_RX_HAUP_EXT */
+ "ir_video", /* IVTV_HW_I2C_IR_RX_HAUP_INT */
+ "ir_tx_z8f0811_haup", /* IVTV_HW_Z8F0811_IR_TX_HAUP */
+ "ir_rx_z8f0811_haup", /* IVTV_HW_Z8F0811_IR_RX_HAUP */
+ "ir_video", /* IVTV_HW_I2C_IR_RX_ADAPTEC */
+};
+
+static int get_key_adaptec(struct IR_i2c *ir, u32 *ir_key, u32 *ir_raw)
+{
+ 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)) {
+ return 0;
+ }
+
+ /* key pressed ? */
+ if (keybuf[2] == 0xff)
+ return 0;
+
+ /* remove repeat bit */
+ keybuf[2] &= 0x7f;
+ keybuf[3] |= 0x80;
+
+ *ir_key = keybuf[3] | keybuf[2] << 8 | keybuf[1] << 16 |keybuf[0] << 24;
+ *ir_raw = *ir_key;
+
+ return 1;
+}
+
+static int ivtv_i2c_new_ir(struct ivtv *itv, u32 hw, const char *type, u8 addr)
+{
+ struct i2c_board_info info;
+ struct i2c_adapter *adap = &itv->i2c_adap;
+ struct IR_i2c_init_data *init_data = &itv->ir_i2c_init_data;
+ unsigned short addr_list[2] = { addr, I2C_CLIENT_END };
+
+ /* Only allow one IR transmitter to be registered per board */
+ if (hw & IVTV_HW_IR_TX_ANY) {
+ if (itv->hw_flags & IVTV_HW_IR_TX_ANY)
+ return -1;
+ memset(&info, 0, sizeof(struct i2c_board_info));
+ strlcpy(info.type, type, I2C_NAME_SIZE);
+ return i2c_new_probed_device(adap, &info, addr_list, NULL)
+ == NULL ? -1 : 0;
+ }
+
+ /* Only allow one IR receiver to be registered per board */
+ if (itv->hw_flags & IVTV_HW_IR_RX_ANY)
+ return -1;
+
+ /* Our default information for ir-kbd-i2c.c to use */
+ switch (hw) {
+ case IVTV_HW_I2C_IR_RX_AVER:
+ init_data->ir_codes = RC_MAP_AVERMEDIA_CARDBUS;
+ init_data->internal_get_key_func =
+ IR_KBD_GET_KEY_AVERMEDIA_CARDBUS;
+ init_data->type = RC_TYPE_OTHER;
+ init_data->name = "AVerMedia AVerTV card";
+ break;
+ case IVTV_HW_I2C_IR_RX_HAUP_EXT:
+ case IVTV_HW_I2C_IR_RX_HAUP_INT:
+ init_data->ir_codes = RC_MAP_HAUPPAUGE;
+ init_data->internal_get_key_func = IR_KBD_GET_KEY_HAUP;
+ init_data->type = RC_TYPE_RC5;
+ init_data->name = itv->card_name;
+ break;
+ case IVTV_HW_Z8F0811_IR_RX_HAUP:
+ /* Default to grey remote */
+ init_data->ir_codes = RC_MAP_HAUPPAUGE;
+ init_data->internal_get_key_func = IR_KBD_GET_KEY_HAUP_XVR;
+ init_data->type = RC_TYPE_RC5;
+ init_data->name = itv->card_name;
+ break;
+ case IVTV_HW_I2C_IR_RX_ADAPTEC:
+ init_data->get_key = get_key_adaptec;
+ init_data->name = itv->card_name;
+ /* FIXME: The protocol and RC_MAP needs to be corrected */
+ init_data->ir_codes = RC_MAP_EMPTY;
+ init_data->type = RC_TYPE_UNKNOWN;
+ break;
+ }
+
+ memset(&info, 0, sizeof(struct i2c_board_info));
+ info.platform_data = init_data;
+ strlcpy(info.type, type, I2C_NAME_SIZE);
+
+ return i2c_new_probed_device(adap, &info, addr_list, NULL) == NULL ?
+ -1 : 0;
+}
+
+/* Instantiate the IR receiver device using probing -- undesirable */
+struct i2c_client *ivtv_i2c_new_ir_legacy(struct ivtv *itv)
+{
+ struct i2c_board_info info;
+ /*
+ * The external IR receiver is at i2c address 0x34.
+ * The internal IR receiver is at i2c address 0x30.
+ *
+ * In theory, both can be fitted, and Hauppauge suggests an external
+ * overrides an internal. That's why we probe 0x1a (~0x34) first. CB
+ *
+ * Some of these addresses we probe may collide with other i2c address
+ * allocations, so this function must be called after all other i2c
+ * devices we care about are registered.
+ */
+ const unsigned short addr_list[] = {
+ 0x1a, /* Hauppauge IR external - collides with WM8739 */
+ 0x18, /* Hauppauge IR internal */
+ I2C_CLIENT_END
+ };
+
+ memset(&info, 0, sizeof(struct i2c_board_info));
+ strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
+ return i2c_new_probed_device(&itv->i2c_adap, &info, addr_list, NULL);
+}
+
+int ivtv_i2c_register(struct ivtv *itv, unsigned idx)
+{
+ struct v4l2_subdev *sd;
+ struct i2c_adapter *adap = &itv->i2c_adap;
+ const char *type = hw_devicenames[idx];
+ u32 hw = 1 << idx;
+
+ if (idx >= ARRAY_SIZE(hw_addrs))
+ return -1;
+ if (hw == IVTV_HW_TUNER) {
+ /* special tuner handling */
+ sd = v4l2_i2c_new_subdev(&itv->v4l2_dev, adap, type, 0,
+ itv->card_i2c->radio);
+ if (sd)
+ sd->grp_id = 1 << idx;
+ sd = v4l2_i2c_new_subdev(&itv->v4l2_dev, adap, type, 0,
+ itv->card_i2c->demod);
+ if (sd)
+ sd->grp_id = 1 << idx;
+ sd = v4l2_i2c_new_subdev(&itv->v4l2_dev, adap, type, 0,
+ itv->card_i2c->tv);
+ if (sd)
+ sd->grp_id = 1 << idx;
+ return sd ? 0 : -1;
+ }
+
+ if (hw & IVTV_HW_IR_ANY)
+ return ivtv_i2c_new_ir(itv, hw, type, hw_addrs[idx]);
+
+ /* Is it not an I2C device or one we do not wish to register? */
+ if (!hw_addrs[idx])
+ return -1;
+
+ /* It's an I2C device other than an analog tuner or IR chip */
+ if (hw == IVTV_HW_UPD64031A || hw == IVTV_HW_UPD6408X) {
+ sd = v4l2_i2c_new_subdev(&itv->v4l2_dev,
+ adap, type, 0, I2C_ADDRS(hw_addrs[idx]));
+ } else if (hw == IVTV_HW_CX25840) {
+ struct cx25840_platform_data pdata;
+ struct i2c_board_info cx25840_info = {
+ .type = "cx25840",
+ .addr = hw_addrs[idx],
+ .platform_data = &pdata,
+ };
+
+ pdata.pvr150_workaround = itv->pvr150_workaround;
+ sd = v4l2_i2c_new_subdev_board(&itv->v4l2_dev, adap,
+ &cx25840_info, NULL);
+ } else {
+ sd = v4l2_i2c_new_subdev(&itv->v4l2_dev,
+ adap, type, hw_addrs[idx], NULL);
+ }
+ if (sd)
+ sd->grp_id = 1 << idx;
+ return sd ? 0 : -1;
+}
+
+struct v4l2_subdev *ivtv_find_hw(struct ivtv *itv, u32 hw)
+{
+ struct v4l2_subdev *result = NULL;
+ struct v4l2_subdev *sd;
+
+ spin_lock(&itv->v4l2_dev.lock);
+ v4l2_device_for_each_subdev(sd, &itv->v4l2_dev) {
+ if (sd->grp_id == hw) {
+ result = sd;
+ break;
+ }
+ }
+ spin_unlock(&itv->v4l2_dev.lock);
+ return result;
+}
+
+/* Set the serial clock line to the desired state */
+static void ivtv_setscl(struct ivtv *itv, int state)
+{
+ /* write them out */
+ /* write bits are inverted */
+ write_reg(~state, IVTV_REG_I2C_SETSCL_OFFSET);
+}
+
+/* Set the serial data line to the desired state */
+static void ivtv_setsda(struct ivtv *itv, int state)
+{
+ /* write them out */
+ /* write bits are inverted */
+ write_reg(~state & 1, IVTV_REG_I2C_SETSDA_OFFSET);
+}
+
+/* Read the serial clock line */
+static int ivtv_getscl(struct ivtv *itv)
+{
+ return read_reg(IVTV_REG_I2C_GETSCL_OFFSET) & 1;
+}
+
+/* Read the serial data line */
+static int ivtv_getsda(struct ivtv *itv)
+{
+ return read_reg(IVTV_REG_I2C_GETSDA_OFFSET) & 1;
+}
+
+/* Implement a short delay by polling the serial clock line */
+static void ivtv_scldelay(struct ivtv *itv)
+{
+ int i;
+
+ for (i = 0; i < 5; ++i)
+ ivtv_getscl(itv);
+}
+
+/* Wait for the serial clock line to become set to a specific value */
+static int ivtv_waitscl(struct ivtv *itv, int val)
+{
+ int i;
+
+ ivtv_scldelay(itv);
+ for (i = 0; i < 1000; ++i) {
+ if (ivtv_getscl(itv) == val)
+ return 1;
+ }
+ return 0;
+}
+
+/* Wait for the serial data line to become set to a specific value */
+static int ivtv_waitsda(struct ivtv *itv, int val)
+{
+ int i;
+
+ ivtv_scldelay(itv);
+ for (i = 0; i < 1000; ++i) {
+ if (ivtv_getsda(itv) == val)
+ return 1;
+ }
+ return 0;
+}
+
+/* Wait for the slave to issue an ACK */
+static int ivtv_ack(struct ivtv *itv)
+{
+ int ret = 0;
+
+ if (ivtv_getscl(itv) == 1) {
+ IVTV_DEBUG_HI_I2C("SCL was high starting an ack\n");
+ ivtv_setscl(itv, 0);
+ if (!ivtv_waitscl(itv, 0)) {
+ IVTV_DEBUG_I2C("Could not set SCL low starting an ack\n");
+ return -EREMOTEIO;
+ }
+ }
+ ivtv_setsda(itv, 1);
+ ivtv_scldelay(itv);
+ ivtv_setscl(itv, 1);
+ if (!ivtv_waitsda(itv, 0)) {
+ IVTV_DEBUG_I2C("Slave did not ack\n");
+ ret = -EREMOTEIO;
+ }
+ ivtv_setscl(itv, 0);
+ if (!ivtv_waitscl(itv, 0)) {
+ IVTV_DEBUG_I2C("Failed to set SCL low after ACK\n");
+ ret = -EREMOTEIO;
+ }
+ return ret;
+}
+
+/* Write a single byte to the i2c bus and wait for the slave to ACK */
+static int ivtv_sendbyte(struct ivtv *itv, unsigned char byte)
+{
+ int i, bit;
+
+ IVTV_DEBUG_HI_I2C("write %x\n",byte);
+ for (i = 0; i < 8; ++i, byte<<=1) {
+ ivtv_setscl(itv, 0);
+ if (!ivtv_waitscl(itv, 0)) {
+ IVTV_DEBUG_I2C("Error setting SCL low\n");
+ return -EREMOTEIO;
+ }
+ bit = (byte>>7)&1;
+ ivtv_setsda(itv, bit);
+ if (!ivtv_waitsda(itv, bit)) {
+ IVTV_DEBUG_I2C("Error setting SDA\n");
+ return -EREMOTEIO;
+ }
+ ivtv_setscl(itv, 1);
+ if (!ivtv_waitscl(itv, 1)) {
+ IVTV_DEBUG_I2C("Slave not ready for bit\n");
+ return -EREMOTEIO;
+ }
+ }
+ ivtv_setscl(itv, 0);
+ if (!ivtv_waitscl(itv, 0)) {
+ IVTV_DEBUG_I2C("Error setting SCL low\n");
+ return -EREMOTEIO;
+ }
+ return ivtv_ack(itv);
+}
+
+/* Read a byte from the i2c bus and send a NACK if applicable (i.e. for the
+ final byte) */
+static int ivtv_readbyte(struct ivtv *itv, unsigned char *byte, int nack)
+{
+ int i;
+
+ *byte = 0;
+
+ ivtv_setsda(itv, 1);
+ ivtv_scldelay(itv);
+ for (i = 0; i < 8; ++i) {
+ ivtv_setscl(itv, 0);
+ ivtv_scldelay(itv);
+ ivtv_setscl(itv, 1);
+ if (!ivtv_waitscl(itv, 1)) {
+ IVTV_DEBUG_I2C("Error setting SCL high\n");
+ return -EREMOTEIO;
+ }
+ *byte = ((*byte)<<1)|ivtv_getsda(itv);
+ }
+ ivtv_setscl(itv, 0);
+ ivtv_scldelay(itv);
+ ivtv_setsda(itv, nack);
+ ivtv_scldelay(itv);
+ ivtv_setscl(itv, 1);
+ ivtv_scldelay(itv);
+ ivtv_setscl(itv, 0);
+ ivtv_scldelay(itv);
+ IVTV_DEBUG_HI_I2C("read %x\n",*byte);
+ return 0;
+}
+
+/* Issue a start condition on the i2c bus to alert slaves to prepare for
+ an address write */
+static int ivtv_start(struct ivtv *itv)
+{
+ int sda;
+
+ sda = ivtv_getsda(itv);
+ if (sda != 1) {
+ IVTV_DEBUG_HI_I2C("SDA was low at start\n");
+ ivtv_setsda(itv, 1);
+ if (!ivtv_waitsda(itv, 1)) {
+ IVTV_DEBUG_I2C("SDA stuck low\n");
+ return -EREMOTEIO;
+ }
+ }
+ if (ivtv_getscl(itv) != 1) {
+ ivtv_setscl(itv, 1);
+ if (!ivtv_waitscl(itv, 1)) {
+ IVTV_DEBUG_I2C("SCL stuck low at start\n");
+ return -EREMOTEIO;
+ }
+ }
+ ivtv_setsda(itv, 0);
+ ivtv_scldelay(itv);
+ return 0;
+}
+
+/* Issue a stop condition on the i2c bus to release it */
+static int ivtv_stop(struct ivtv *itv)
+{
+ int i;
+
+ if (ivtv_getscl(itv) != 0) {
+ IVTV_DEBUG_HI_I2C("SCL not low when stopping\n");
+ ivtv_setscl(itv, 0);
+ if (!ivtv_waitscl(itv, 0)) {
+ IVTV_DEBUG_I2C("SCL could not be set low\n");
+ }
+ }
+ ivtv_setsda(itv, 0);
+ ivtv_scldelay(itv);
+ ivtv_setscl(itv, 1);
+ if (!ivtv_waitscl(itv, 1)) {
+ IVTV_DEBUG_I2C("SCL could not be set high\n");
+ return -EREMOTEIO;
+ }
+ ivtv_scldelay(itv);
+ ivtv_setsda(itv, 1);
+ if (!ivtv_waitsda(itv, 1)) {
+ IVTV_DEBUG_I2C("resetting I2C\n");
+ for (i = 0; i < 16; ++i) {
+ ivtv_setscl(itv, 0);
+ ivtv_scldelay(itv);
+ ivtv_setscl(itv, 1);
+ ivtv_scldelay(itv);
+ ivtv_setsda(itv, 1);
+ }
+ ivtv_waitsda(itv, 1);
+ return -EREMOTEIO;
+ }
+ return 0;
+}
+
+/* Write a message to the given i2c slave. do_stop may be 0 to prevent
+ issuing the i2c stop condition (when following with a read) */
+static int ivtv_write(struct ivtv *itv, unsigned char addr, unsigned char *data, u32 len, int do_stop)
+{
+ int retry, ret = -EREMOTEIO;
+ u32 i;
+
+ for (retry = 0; ret != 0 && retry < 8; ++retry) {
+ ret = ivtv_start(itv);
+
+ if (ret == 0) {
+ ret = ivtv_sendbyte(itv, addr<<1);
+ for (i = 0; ret == 0 && i < len; ++i)
+ ret = ivtv_sendbyte(itv, data[i]);
+ }
+ if (ret != 0 || do_stop) {
+ ivtv_stop(itv);
+ }
+ }
+ if (ret)
+ IVTV_DEBUG_I2C("i2c write to %x failed\n", addr);
+ return ret;
+}
+
+/* Read data from the given i2c slave. A stop condition is always issued. */
+static int ivtv_read(struct ivtv *itv, unsigned char addr, unsigned char *data, u32 len)
+{
+ int retry, ret = -EREMOTEIO;
+ u32 i;
+
+ for (retry = 0; ret != 0 && retry < 8; ++retry) {
+ ret = ivtv_start(itv);
+ if (ret == 0)
+ ret = ivtv_sendbyte(itv, (addr << 1) | 1);
+ for (i = 0; ret == 0 && i < len; ++i) {
+ ret = ivtv_readbyte(itv, &data[i], i == len - 1);
+ }
+ ivtv_stop(itv);
+ }
+ if (ret)
+ IVTV_DEBUG_I2C("i2c read from %x failed\n", addr);
+ return ret;
+}
+
+/* Kernel i2c transfer implementation. Takes a number of messages to be read
+ or written. If a read follows a write, this will occur without an
+ intervening stop condition */
+static int ivtv_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
+{
+ struct v4l2_device *v4l2_dev = i2c_get_adapdata(i2c_adap);
+ struct ivtv *itv = to_ivtv(v4l2_dev);
+ int retval;
+ int i;
+
+ mutex_lock(&itv->i2c_bus_lock);
+ for (i = retval = 0; retval == 0 && i < num; i++) {
+ if (msgs[i].flags & I2C_M_RD)
+ retval = ivtv_read(itv, msgs[i].addr, msgs[i].buf, msgs[i].len);
+ else {
+ /* if followed by a read, don't stop */
+ int stop = !(i + 1 < num && msgs[i + 1].flags == I2C_M_RD);
+
+ retval = ivtv_write(itv, msgs[i].addr, msgs[i].buf, msgs[i].len, stop);
+ }
+ }
+ mutex_unlock(&itv->i2c_bus_lock);
+ return retval ? retval : num;
+}
+
+/* Kernel i2c capabilities */
+static u32 ivtv_functionality(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static struct i2c_algorithm ivtv_algo = {
+ .master_xfer = ivtv_xfer,
+ .functionality = ivtv_functionality,
+};
+
+/* template for our-bit banger */
+static struct i2c_adapter ivtv_i2c_adap_hw_template = {
+ .name = "ivtv i2c driver",
+ .algo = &ivtv_algo,
+ .algo_data = NULL, /* filled from template */
+ .owner = THIS_MODULE,
+};
+
+static void ivtv_setscl_old(void *data, int state)
+{
+ struct ivtv *itv = (struct ivtv *)data;
+
+ if (state)
+ itv->i2c_state |= 0x01;
+ else
+ itv->i2c_state &= ~0x01;
+
+ /* write them out */
+ /* write bits are inverted */
+ write_reg(~itv->i2c_state, IVTV_REG_I2C_SETSCL_OFFSET);
+}
+
+static void ivtv_setsda_old(void *data, int state)
+{
+ struct ivtv *itv = (struct ivtv *)data;
+
+ if (state)
+ itv->i2c_state |= 0x01;
+ else
+ itv->i2c_state &= ~0x01;
+
+ /* write them out */
+ /* write bits are inverted */
+ write_reg(~itv->i2c_state, IVTV_REG_I2C_SETSDA_OFFSET);
+}
+
+static int ivtv_getscl_old(void *data)
+{
+ struct ivtv *itv = (struct ivtv *)data;
+
+ return read_reg(IVTV_REG_I2C_GETSCL_OFFSET) & 1;
+}
+
+static int ivtv_getsda_old(void *data)
+{
+ struct ivtv *itv = (struct ivtv *)data;
+
+ return read_reg(IVTV_REG_I2C_GETSDA_OFFSET) & 1;
+}
+
+/* template for i2c-bit-algo */
+static struct i2c_adapter ivtv_i2c_adap_template = {
+ .name = "ivtv i2c driver",
+ .algo = NULL, /* set by i2c-algo-bit */
+ .algo_data = NULL, /* filled from template */
+ .owner = THIS_MODULE,
+};
+
+#define IVTV_ALGO_BIT_TIMEOUT (2) /* seconds */
+
+static const struct i2c_algo_bit_data ivtv_i2c_algo_template = {
+ .setsda = ivtv_setsda_old,
+ .setscl = ivtv_setscl_old,
+ .getsda = ivtv_getsda_old,
+ .getscl = ivtv_getscl_old,
+ .udelay = IVTV_DEFAULT_I2C_CLOCK_PERIOD / 2, /* microseconds */
+ .timeout = IVTV_ALGO_BIT_TIMEOUT * HZ, /* jiffies */
+};
+
+static struct i2c_client ivtv_i2c_client_template = {
+ .name = "ivtv internal",
+};
+
+/* init + register i2c adapter */
+int init_ivtv_i2c(struct ivtv *itv)
+{
+ int retval;
+
+ IVTV_DEBUG_I2C("i2c init\n");
+
+ /* Sanity checks for the I2C hardware arrays. They must be the
+ * same size.
+ */
+ if (ARRAY_SIZE(hw_devicenames) != ARRAY_SIZE(hw_addrs)) {
+ IVTV_ERR("Mismatched I2C hardware arrays\n");
+ return -ENODEV;
+ }
+ if (itv->options.newi2c > 0) {
+ memcpy(&itv->i2c_adap, &ivtv_i2c_adap_hw_template,
+ sizeof(struct i2c_adapter));
+ } else {
+ memcpy(&itv->i2c_adap, &ivtv_i2c_adap_template,
+ sizeof(struct i2c_adapter));
+ memcpy(&itv->i2c_algo, &ivtv_i2c_algo_template,
+ sizeof(struct i2c_algo_bit_data));
+ }
+ itv->i2c_algo.udelay = itv->options.i2c_clock_period / 2;
+ itv->i2c_algo.data = itv;
+ itv->i2c_adap.algo_data = &itv->i2c_algo;
+
+ sprintf(itv->i2c_adap.name + strlen(itv->i2c_adap.name), " #%d",
+ itv->instance);
+ i2c_set_adapdata(&itv->i2c_adap, &itv->v4l2_dev);
+
+ memcpy(&itv->i2c_client, &ivtv_i2c_client_template,
+ sizeof(struct i2c_client));
+ itv->i2c_client.adapter = &itv->i2c_adap;
+ itv->i2c_adap.dev.parent = &itv->pdev->dev;
+
+ IVTV_DEBUG_I2C("setting scl and sda to 1\n");
+ ivtv_setscl(itv, 1);
+ ivtv_setsda(itv, 1);
+
+ if (itv->options.newi2c > 0)
+ retval = i2c_add_adapter(&itv->i2c_adap);
+ else
+ retval = i2c_bit_add_bus(&itv->i2c_adap);
+
+ return retval;
+}
+
+void exit_ivtv_i2c(struct ivtv *itv)
+{
+ IVTV_DEBUG_I2C("i2c exit\n");
+
+ i2c_del_adapter(&itv->i2c_adap);
+}
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