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[media] em28xx: add support for registering multiple i2c buses
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Register both buses 0 and 1 via I2C API. For now, bus 0 is used
only by eeprom on all known devices. Later patches will be needed
if this changes in the future.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
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Mauro Carvalho Chehab committed Mar 18, 2013
1 parent 3aa2b3b commit aab3125
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Showing 3 changed files with 120 additions and 51 deletions.
31 changes: 23 additions & 8 deletions drivers/media/usb/em28xx/em28xx-cards.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2235,8 +2235,8 @@ static inline void em28xx_set_model(struct em28xx *dev)
dev->board.i2c_speed = EM28XX_I2C_CLK_WAIT_ENABLE |
EM28XX_I2C_FREQ_100_KHZ;

if (dev->board.def_i2c_bus == 1)
dev->board.i2c_speed |= EM2874_I2C_SECONDARY_BUS_SELECT;
/* Should be initialized early, for I2C to work */
dev->def_i2c_bus = dev->board.def_i2c_bus;
}


Expand Down Expand Up @@ -2642,7 +2642,7 @@ static int em28xx_hint_board(struct em28xx *dev)

/* user did not request i2c scanning => do it now */
if (!dev->i2c_hash)
em28xx_do_i2c_scan(dev);
em28xx_do_i2c_scan(dev, dev->def_i2c_bus);

for (i = 0; i < ARRAY_SIZE(em28xx_i2c_hash); i++) {
if (dev->i2c_hash == em28xx_i2c_hash[i].hash) {
Expand Down Expand Up @@ -2953,7 +2953,9 @@ void em28xx_release_resources(struct em28xx *dev)

em28xx_release_analog_resources(dev);

em28xx_i2c_unregister(dev);
if (dev->def_i2c_bus)
em28xx_i2c_unregister(dev, 1);
em28xx_i2c_unregister(dev, 0);

v4l2_ctrl_handler_free(&dev->ctrl_handler);

Expand Down Expand Up @@ -3109,14 +3111,25 @@ static int em28xx_init_dev(struct em28xx *dev, struct usb_device *udev,
v4l2_ctrl_handler_init(hdl, 8);
dev->v4l2_dev.ctrl_handler = hdl;

/* register i2c bus */
retval = em28xx_i2c_register(dev);
rt_mutex_init(&dev->i2c_bus_lock);

/* register i2c bus 0 */
retval = em28xx_i2c_register(dev, 0);
if (retval < 0) {
em28xx_errdev("%s: em28xx_i2c_register - error [%d]!\n",
em28xx_errdev("%s: em28xx_i2c_register bus 0 - error [%d]!\n",
__func__, retval);
goto unregister_dev;
}

if (dev->def_i2c_bus) {
retval = em28xx_i2c_register(dev, 1);
if (retval < 0) {
em28xx_errdev("%s: em28xx_i2c_register bus 1 - error [%d]!\n",
__func__, retval);
goto unregister_dev;
}
}

/*
* Default format, used for tvp5150 or saa711x output formats
*/
Expand Down Expand Up @@ -3186,7 +3199,9 @@ static int em28xx_init_dev(struct em28xx *dev, struct usb_device *udev,
return 0;

fail:
em28xx_i2c_unregister(dev);
if (dev->def_i2c_bus)
em28xx_i2c_unregister(dev, 1);
em28xx_i2c_unregister(dev, 0);
v4l2_ctrl_handler_free(&dev->ctrl_handler);

unregister_dev:
Expand Down
119 changes: 81 additions & 38 deletions drivers/media/usb/em28xx/em28xx-i2c.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -280,11 +280,29 @@ static int em28xx_i2c_check_for_device(struct em28xx *dev, u16 addr)
static int em28xx_i2c_xfer(struct i2c_adapter *i2c_adap,
struct i2c_msg msgs[], int num)
{
struct em28xx *dev = i2c_adap->algo_data;
struct em28xx_i2c_bus *i2c_bus = i2c_adap->algo_data;
struct em28xx *dev = i2c_bus->dev;
unsigned bus = i2c_bus->bus;
int addr, rc, i, byte;

if (num <= 0)
rc = rt_mutex_trylock(&dev->i2c_bus_lock);
if (rc < 0)
return rc;

/* Switch I2C bus if needed */
if (bus != dev->cur_i2c_bus) {
if (bus == 1)
dev->cur_i2c_bus |= EM2874_I2C_SECONDARY_BUS_SELECT;
else
dev->cur_i2c_bus &= ~EM2874_I2C_SECONDARY_BUS_SELECT;
em28xx_write_reg(dev, EM28XX_R06_I2C_CLK, dev->cur_i2c_bus);
dev->cur_i2c_bus = bus;
}

if (num <= 0) {
rt_mutex_unlock(&dev->i2c_bus_lock);
return 0;
}
for (i = 0; i < num; i++) {
addr = msgs[i].addr << 1;
if (i2c_debug)
Expand All @@ -301,6 +319,7 @@ static int em28xx_i2c_xfer(struct i2c_adapter *i2c_adap,
if (rc == -ENODEV) {
if (i2c_debug)
printk(" no device\n");
rt_mutex_unlock(&dev->i2c_bus_lock);
return rc;
}
} else if (msgs[i].flags & I2C_M_RD) {
Expand Down Expand Up @@ -336,12 +355,14 @@ static int em28xx_i2c_xfer(struct i2c_adapter *i2c_adap,
if (rc < 0) {
if (i2c_debug)
printk(" ERROR: %i\n", rc);
rt_mutex_unlock(&dev->i2c_bus_lock);
return rc;
}
if (i2c_debug)
printk("\n");
}

rt_mutex_unlock(&dev->i2c_bus_lock);
return num;
}

Expand Down Expand Up @@ -372,8 +393,8 @@ static inline unsigned long em28xx_hash_mem(char *buf, int length, int bits)

/* Helper function to read data blocks from i2c clients with 8 or 16 bit
* address width, 8 bit register width and auto incrementation been activated */
static int em28xx_i2c_read_block(struct em28xx *dev, u16 addr, bool addr_w16,
u16 len, u8 *data)
static int em28xx_i2c_read_block(struct em28xx *dev, unsigned bus, u16 addr,
bool addr_w16, u16 len, u8 *data)
{
int remain = len, rsize, rsize_max, ret;
u8 buf[2];
Expand All @@ -384,7 +405,7 @@ static int em28xx_i2c_read_block(struct em28xx *dev, u16 addr, bool addr_w16,
/* Select address */
buf[0] = addr >> 8;
buf[1] = addr & 0xff;
ret = i2c_master_send(&dev->i2c_client[dev->def_i2c_bus], buf + !addr_w16, 1 + addr_w16);
ret = i2c_master_send(&dev->i2c_client[bus], buf + !addr_w16, 1 + addr_w16);
if (ret < 0)
return ret;
/* Read data */
Expand All @@ -398,7 +419,7 @@ static int em28xx_i2c_read_block(struct em28xx *dev, u16 addr, bool addr_w16,
else
rsize = remain;

ret = i2c_master_recv(&dev->i2c_client[dev->def_i2c_bus], data, rsize);
ret = i2c_master_recv(&dev->i2c_client[bus], data, rsize);
if (ret < 0)
return ret;

Expand All @@ -409,7 +430,8 @@ static int em28xx_i2c_read_block(struct em28xx *dev, u16 addr, bool addr_w16,
return len;
}

static int em28xx_i2c_eeprom(struct em28xx *dev, u8 **eedata, u16 *eedata_len)
static int em28xx_i2c_eeprom(struct em28xx *dev, unsigned bus,
u8 **eedata, u16 *eedata_len)
{
const u16 len = 256;
/* FIXME common length/size for bytes to read, to display, hash
Expand All @@ -422,10 +444,12 @@ static int em28xx_i2c_eeprom(struct em28xx *dev, u8 **eedata, u16 *eedata_len)
*eedata = NULL;
*eedata_len = 0;

dev->i2c_client[dev->def_i2c_bus].addr = 0xa0 >> 1;
/* EEPROM is always on i2c bus 0 on all known devices. */

dev->i2c_client[bus].addr = 0xa0 >> 1;

/* Check if board has eeprom */
err = i2c_master_recv(&dev->i2c_client[dev->def_i2c_bus], &buf, 0);
err = i2c_master_recv(&dev->i2c_client[bus], &buf, 0);
if (err < 0) {
em28xx_info("board has no eeprom\n");
return -ENODEV;
Expand All @@ -436,7 +460,8 @@ static int em28xx_i2c_eeprom(struct em28xx *dev, u8 **eedata, u16 *eedata_len)
return -ENOMEM;

/* Read EEPROM content */
err = em28xx_i2c_read_block(dev, 0x0000, dev->eeprom_addrwidth_16bit,
err = em28xx_i2c_read_block(dev, bus, 0x0000,
dev->eeprom_addrwidth_16bit,
len, data);
if (err != len) {
em28xx_errdev("failed to read eeprom (err=%d)\n", err);
Expand Down Expand Up @@ -485,7 +510,8 @@ static int em28xx_i2c_eeprom(struct em28xx *dev, u8 **eedata, u16 *eedata_len)

/* Read hardware config dataset offset from address
* (microcode start + 46) */
err = em28xx_i2c_read_block(dev, mc_start + 46, 1, 2, data);
err = em28xx_i2c_read_block(dev, bus, mc_start + 46, 1, 2,
data);
if (err != 2) {
em28xx_errdev("failed to read hardware configuration data from eeprom (err=%d)\n",
err);
Expand All @@ -501,7 +527,8 @@ static int em28xx_i2c_eeprom(struct em28xx *dev, u8 **eedata, u16 *eedata_len)
* the old eeprom and not longer than 256 bytes.
* tveeprom is currently also limited to 256 bytes.
*/
err = em28xx_i2c_read_block(dev, hwconf_offset, 1, len, data);
err = em28xx_i2c_read_block(dev, bus, hwconf_offset, 1, len,
data);
if (err != len) {
em28xx_errdev("failed to read hardware configuration data from eeprom (err=%d)\n",
err);
Expand Down Expand Up @@ -590,9 +617,11 @@ static int em28xx_i2c_eeprom(struct em28xx *dev, u8 **eedata, u16 *eedata_len)
/*
* functionality()
*/
static u32 functionality(struct i2c_adapter *adap)
static u32 functionality(struct i2c_adapter *i2c_adap)
{
struct em28xx *dev = adap->algo_data;
struct em28xx_i2c_bus *i2c_bus = i2c_adap->algo_data;
struct em28xx *dev = i2c_bus->dev;

u32 func_flags = I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
if (dev->board.is_em2800)
func_flags &= ~I2C_FUNC_SMBUS_WRITE_BLOCK_DATA;
Expand Down Expand Up @@ -643,7 +672,7 @@ static char *i2c_devs[128] = {
* do_i2c_scan()
* check i2c address range for devices
*/
void em28xx_do_i2c_scan(struct em28xx *dev)
void em28xx_do_i2c_scan(struct em28xx *dev, unsigned bus)
{
u8 i2c_devicelist[128];
unsigned char buf;
Expand All @@ -652,55 +681,66 @@ void em28xx_do_i2c_scan(struct em28xx *dev)
memset(i2c_devicelist, 0, ARRAY_SIZE(i2c_devicelist));

for (i = 0; i < ARRAY_SIZE(i2c_devs); i++) {
dev->i2c_client[dev->def_i2c_bus].addr = i;
rc = i2c_master_recv(&dev->i2c_client[dev->def_i2c_bus], &buf, 0);
dev->i2c_client[bus].addr = i;
rc = i2c_master_recv(&dev->i2c_client[bus], &buf, 0);
if (rc < 0)
continue;
i2c_devicelist[i] = i;
em28xx_info("found i2c device @ 0x%x [%s]\n",
i << 1, i2c_devs[i] ? i2c_devs[i] : "???");
em28xx_info("found i2c device @ 0x%x on bus %d [%s]\n",
i << 1, bus, i2c_devs[i] ? i2c_devs[i] : "???");
}

dev->i2c_hash = em28xx_hash_mem(i2c_devicelist,
ARRAY_SIZE(i2c_devicelist), 32);
if (bus == dev->def_i2c_bus)
dev->i2c_hash = em28xx_hash_mem(i2c_devicelist,
ARRAY_SIZE(i2c_devicelist), 32);
}

/*
* em28xx_i2c_register()
* register i2c bus
*/
int em28xx_i2c_register(struct em28xx *dev)
int em28xx_i2c_register(struct em28xx *dev, unsigned bus)
{
int retval;

BUG_ON(!dev->em28xx_write_regs || !dev->em28xx_read_reg);
BUG_ON(!dev->em28xx_write_regs_req || !dev->em28xx_read_reg_req);
dev->i2c_adap[dev->def_i2c_bus] = em28xx_adap_template;
dev->i2c_adap[dev->def_i2c_bus].dev.parent = &dev->udev->dev;
strcpy(dev->i2c_adap[dev->def_i2c_bus].name, dev->name);
dev->i2c_adap[dev->def_i2c_bus].algo_data = dev;
i2c_set_adapdata(&dev->i2c_adap[dev->def_i2c_bus], &dev->v4l2_dev);

retval = i2c_add_adapter(&dev->i2c_adap[dev->def_i2c_bus]);
if (bus >= NUM_I2C_BUSES)
return -ENODEV;

dev->i2c_adap[bus] = em28xx_adap_template;
dev->i2c_adap[bus].dev.parent = &dev->udev->dev;
strcpy(dev->i2c_adap[bus].name, dev->name);

dev->i2c_bus[bus].bus = bus;
dev->i2c_bus[bus].dev = dev;
dev->i2c_adap[bus].algo_data = &dev->i2c_bus[bus];
i2c_set_adapdata(&dev->i2c_adap[bus], &dev->v4l2_dev);

retval = i2c_add_adapter(&dev->i2c_adap[bus]);
if (retval < 0) {
em28xx_errdev("%s: i2c_add_adapter failed! retval [%d]\n",
__func__, retval);
return retval;
}

dev->i2c_client[dev->def_i2c_bus] = em28xx_client_template;
dev->i2c_client[dev->def_i2c_bus].adapter = &dev->i2c_adap[dev->def_i2c_bus];
dev->i2c_client[bus] = em28xx_client_template;
dev->i2c_client[bus].adapter = &dev->i2c_adap[bus];

retval = em28xx_i2c_eeprom(dev, &dev->eedata, &dev->eedata_len);
if ((retval < 0) && (retval != -ENODEV)) {
em28xx_errdev("%s: em28xx_i2_eeprom failed! retval [%d]\n",
__func__, retval);
/* Up to now, all eeproms are at bus 0 */
if (!bus) {
retval = em28xx_i2c_eeprom(dev, bus, &dev->eedata, &dev->eedata_len);
if ((retval < 0) && (retval != -ENODEV)) {
em28xx_errdev("%s: em28xx_i2_eeprom failed! retval [%d]\n",
__func__, retval);

return retval;
return retval;
}
}

if (i2c_scan)
em28xx_do_i2c_scan(dev);
em28xx_do_i2c_scan(dev, bus);

return 0;
}
Expand All @@ -709,8 +749,11 @@ int em28xx_i2c_register(struct em28xx *dev)
* em28xx_i2c_unregister()
* unregister i2c_bus
*/
int em28xx_i2c_unregister(struct em28xx *dev)
int em28xx_i2c_unregister(struct em28xx *dev, unsigned bus)
{
i2c_del_adapter(&dev->i2c_adap[dev->def_i2c_bus]);
if (bus >= NUM_I2C_BUSES)
return -ENODEV;

i2c_del_adapter(&dev->i2c_adap[bus]);
return 0;
}
21 changes: 16 additions & 5 deletions drivers/media/usb/em28xx/em28xx.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -375,7 +375,7 @@ struct em28xx_board {
int vchannels;
int tuner_type;
int tuner_addr;
int def_i2c_bus; /* Default I2C bus */
unsigned def_i2c_bus; /* Default I2C bus */

/* i2c flags */
unsigned int tda9887_conf;
Expand Down Expand Up @@ -460,6 +460,13 @@ struct em28xx_fh {
enum v4l2_buf_type type;
};

struct em28xx_i2c_bus {
struct em28xx *dev;

unsigned bus;
};


/* main device struct */
struct em28xx {
/* generic device properties */
Expand Down Expand Up @@ -515,8 +522,12 @@ struct em28xx {
/* i2c i/o */
struct i2c_adapter i2c_adap[NUM_I2C_BUSES];
struct i2c_client i2c_client[NUM_I2C_BUSES];
struct em28xx_i2c_bus i2c_bus[NUM_I2C_BUSES];

unsigned char eeprom_addrwidth_16bit:1;
int def_i2c_bus; /* Default I2C bus */
unsigned def_i2c_bus; /* Default I2C bus */
unsigned cur_i2c_bus; /* Current I2C bus */
struct rt_mutex i2c_bus_lock;

/* video for linux */
int users; /* user count for exclusive use */
Expand Down Expand Up @@ -638,9 +649,9 @@ struct em28xx_ops {
};

/* Provided by em28xx-i2c.c */
void em28xx_do_i2c_scan(struct em28xx *dev);
int em28xx_i2c_register(struct em28xx *dev);
int em28xx_i2c_unregister(struct em28xx *dev);
void em28xx_do_i2c_scan(struct em28xx *dev, unsigned bus);
int em28xx_i2c_register(struct em28xx *dev, unsigned bus);
int em28xx_i2c_unregister(struct em28xx *dev, unsigned bus);

/* Provided by em28xx-core.c */
int em28xx_read_reg_req_len(struct em28xx *dev, u8 req, u16 reg,
Expand Down

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