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path: root/drivers/media/usb/em28xx/em28xx-i2c.c
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Diffstat (limited to 'drivers/media/usb/em28xx/em28xx-i2c.c')
-rw-r--r--drivers/media/usb/em28xx/em28xx-i2c.c293
1 files changed, 177 insertions, 116 deletions
diff --git a/drivers/media/usb/em28xx/em28xx-i2c.c b/drivers/media/usb/em28xx/em28xx-i2c.c
index 1683bd9d51ee..8532c1d4fd46 100644
--- a/drivers/media/usb/em28xx/em28xx-i2c.c
+++ b/drivers/media/usb/em28xx/em28xx-i2c.c
@@ -50,15 +50,18 @@ do { \
} while (0)
/*
- * em2800_i2c_send_max4()
- * send up to 4 bytes to the i2c device
+ * em2800_i2c_send_bytes()
+ * send up to 4 bytes to the em2800 i2c device
*/
-static int em2800_i2c_send_max4(struct em28xx *dev, unsigned char addr,
- char *buf, int len)
+static int em2800_i2c_send_bytes(struct em28xx *dev, u8 addr, u8 *buf, u16 len)
{
int ret;
int write_timeout;
- unsigned char b2[6];
+ u8 b2[6];
+
+ if (len < 1 || len > 4)
+ return -EOPNOTSUPP;
+
BUG_ON(len < 1 || len > 4);
b2[5] = 0x80 + len - 1;
b2[4] = addr;
@@ -70,165 +73,212 @@ static int em2800_i2c_send_max4(struct em28xx *dev, unsigned char addr,
if (len > 3)
b2[0] = buf[3];
+ /* trigger write */
ret = dev->em28xx_write_regs(dev, 4 - len, &b2[4 - len], 2 + len);
if (ret != 2 + len) {
- em28xx_warn("writing to i2c device failed (error=%i)\n", ret);
- return -EIO;
+ em28xx_warn("failed to trigger write to i2c address 0x%x "
+ "(error=%i)\n", addr, ret);
+ return (ret < 0) ? ret : -EIO;
}
- for (write_timeout = EM2800_I2C_WRITE_TIMEOUT; write_timeout > 0;
+ /* wait for completion */
+ for (write_timeout = EM2800_I2C_XFER_TIMEOUT; write_timeout > 0;
write_timeout -= 5) {
ret = dev->em28xx_read_reg(dev, 0x05);
- if (ret == 0x80 + len - 1)
+ if (ret == 0x80 + len - 1) {
return len;
+ } else if (ret == 0x94 + len - 1) {
+ return -ENODEV;
+ } else if (ret < 0) {
+ em28xx_warn("failed to get i2c transfer status from "
+ "bridge register (error=%i)\n", ret);
+ return ret;
+ }
msleep(5);
}
- em28xx_warn("i2c write timed out\n");
+ em28xx_warn("write to i2c device at 0x%x timed out\n", addr);
return -EIO;
}
/*
- * em2800_i2c_send_bytes()
- */
-static int em2800_i2c_send_bytes(void *data, unsigned char addr, char *buf,
- short len)
-{
- char *bufPtr = buf;
- int ret;
- int wrcount = 0;
- int count;
- int maxLen = 4;
- struct em28xx *dev = (struct em28xx *)data;
- while (len > 0) {
- count = (len > maxLen) ? maxLen : len;
- ret = em2800_i2c_send_max4(dev, addr, bufPtr, count);
- if (ret > 0) {
- len -= count;
- bufPtr += count;
- wrcount += count;
- } else
- return (ret < 0) ? ret : -EFAULT;
- }
- return wrcount;
-}
-
-/*
- * em2800_i2c_check_for_device()
- * check if there is a i2c_device at the supplied address
+ * em2800_i2c_recv_bytes()
+ * read up to 4 bytes from the em2800 i2c device
*/
-static int em2800_i2c_check_for_device(struct em28xx *dev, unsigned char addr)
+static int em2800_i2c_recv_bytes(struct em28xx *dev, u8 addr, u8 *buf, u16 len)
{
- char msg;
+ u8 buf2[4];
int ret;
- int write_timeout;
- msg = addr;
- ret = dev->em28xx_write_regs(dev, 0x04, &msg, 1);
- if (ret < 0) {
- em28xx_warn("setting i2c device address failed (error=%i)\n",
- ret);
- return ret;
- }
- msg = 0x84;
- ret = dev->em28xx_write_regs(dev, 0x05, &msg, 1);
- if (ret < 0) {
- em28xx_warn("preparing i2c read failed (error=%i)\n", ret);
- return ret;
+ int read_timeout;
+ int i;
+
+ if (len < 1 || len > 4)
+ return -EOPNOTSUPP;
+
+ /* trigger read */
+ buf2[1] = 0x84 + len - 1;
+ buf2[0] = addr;
+ ret = dev->em28xx_write_regs(dev, 0x04, buf2, 2);
+ if (ret != 2) {
+ em28xx_warn("failed to trigger read from i2c address 0x%x "
+ "(error=%i)\n", addr, ret);
+ return (ret < 0) ? ret : -EIO;
}
- for (write_timeout = EM2800_I2C_WRITE_TIMEOUT; write_timeout > 0;
- write_timeout -= 5) {
- unsigned reg = dev->em28xx_read_reg(dev, 0x5);
- if (reg == 0x94)
+ /* wait for completion */
+ for (read_timeout = EM2800_I2C_XFER_TIMEOUT; read_timeout > 0;
+ read_timeout -= 5) {
+ ret = dev->em28xx_read_reg(dev, 0x05);
+ if (ret == 0x84 + len - 1) {
+ break;
+ } else if (ret == 0x94 + len - 1) {
return -ENODEV;
- else if (reg == 0x84)
- return 0;
+ } else if (ret < 0) {
+ em28xx_warn("failed to get i2c transfer status from "
+ "bridge register (error=%i)\n", ret);
+ return ret;
+ }
msleep(5);
}
- return -ENODEV;
+ if (ret != 0x84 + len - 1)
+ em28xx_warn("read from i2c device at 0x%x timed out\n", addr);
+
+ /* get the received message */
+ ret = dev->em28xx_read_reg_req_len(dev, 0x00, 4-len, buf2, len);
+ if (ret != len) {
+ em28xx_warn("reading from i2c device at 0x%x failed: "
+ "couldn't get the received message from the bridge "
+ "(error=%i)\n", addr, ret);
+ return (ret < 0) ? ret : -EIO;
+ }
+ for (i = 0; i < len; i++)
+ buf[i] = buf2[len - 1 - i];
+
+ return ret;
}
/*
- * em2800_i2c_recv_bytes()
- * read from the i2c device
+ * em2800_i2c_check_for_device()
+ * check if there is an i2c device at the supplied address
*/
-static int em2800_i2c_recv_bytes(struct em28xx *dev, unsigned char addr,
- char *buf, int len)
+static int em2800_i2c_check_for_device(struct em28xx *dev, u8 addr)
{
+ u8 buf;
int ret;
- /* check for the device and set i2c read address */
- ret = em2800_i2c_check_for_device(dev, addr);
- if (ret) {
- em28xx_warn
- ("preparing read at i2c address 0x%x failed (error=%i)\n",
- addr, ret);
- return ret;
- }
- ret = dev->em28xx_read_reg_req_len(dev, 0x0, 0x3, buf, len);
- if (ret < 0) {
- em28xx_warn("reading from i2c device at 0x%x failed (error=%i)",
- addr, ret);
- return ret;
- }
- return ret;
+
+ ret = em2800_i2c_recv_bytes(dev, addr, &buf, 1);
+ if (ret == 1)
+ return 0;
+ return (ret < 0) ? ret : -EIO;
}
/*
* em28xx_i2c_send_bytes()
*/
-static int em28xx_i2c_send_bytes(void *data, unsigned char addr, char *buf,
- short len, int stop)
+static int em28xx_i2c_send_bytes(struct em28xx *dev, u16 addr, u8 *buf,
+ u16 len, int stop)
{
- int wrcount = 0;
- struct em28xx *dev = (struct em28xx *)data;
int write_timeout, ret;
- wrcount = dev->em28xx_write_regs_req(dev, stop ? 2 : 3, addr, buf, len);
+ if (len < 1 || len > 64)
+ return -EOPNOTSUPP;
+ /* NOTE: limited by the USB ctrl message constraints
+ * Zero length reads always succeed, even if no device is connected */
+
+ /* Write to i2c device */
+ ret = dev->em28xx_write_regs_req(dev, stop ? 2 : 3, addr, buf, len);
+ if (ret != len) {
+ if (ret < 0) {
+ em28xx_warn("writing to i2c device at 0x%x failed "
+ "(error=%i)\n", addr, ret);
+ return ret;
+ } else {
+ em28xx_warn("%i bytes write to i2c device at 0x%x "
+ "requested, but %i bytes written\n",
+ len, addr, ret);
+ return -EIO;
+ }
+ }
- /* Seems to be required after a write */
- for (write_timeout = EM2800_I2C_WRITE_TIMEOUT; write_timeout > 0;
+ /* Check success of the i2c operation */
+ for (write_timeout = EM2800_I2C_XFER_TIMEOUT; write_timeout > 0;
write_timeout -= 5) {
ret = dev->em28xx_read_reg(dev, 0x05);
- if (!ret)
- break;
+ if (ret == 0) { /* success */
+ return len;
+ } else if (ret == 0x10) {
+ return -ENODEV;
+ } else if (ret < 0) {
+ em28xx_warn("failed to read i2c transfer status from "
+ "bridge (error=%i)\n", ret);
+ return ret;
+ }
msleep(5);
+ /* NOTE: do we really have to wait for success ?
+ Never seen anything else than 0x00 or 0x10
+ (even with high payload) ... */
}
-
- return wrcount;
+ em28xx_warn("write to i2c device at 0x%x timed out\n", addr);
+ return -EIO;
}
/*
* em28xx_i2c_recv_bytes()
* read a byte from the i2c device
*/
-static int em28xx_i2c_recv_bytes(struct em28xx *dev, unsigned char addr,
- char *buf, int len)
+static int em28xx_i2c_recv_bytes(struct em28xx *dev, u16 addr, u8 *buf, u16 len)
{
int ret;
+
+ if (len < 1 || len > 64)
+ return -EOPNOTSUPP;
+ /* NOTE: limited by the USB ctrl message constraints
+ * Zero length reads always succeed, even if no device is connected */
+
+ /* Read data from i2c device */
ret = dev->em28xx_read_reg_req_len(dev, 2, addr, buf, len);
+ if (ret != len) {
+ if (ret < 0) {
+ em28xx_warn("reading from i2c device at 0x%x failed "
+ "(error=%i)\n", addr, ret);
+ return ret;
+ } else {
+ em28xx_warn("%i bytes requested from i2c device at "
+ "0x%x, but %i bytes received\n",
+ len, addr, ret);
+ return -EIO;
+ }
+ }
+
+ /* Check success of the i2c operation */
+ ret = dev->em28xx_read_reg(dev, 0x05);
if (ret < 0) {
- em28xx_warn("reading i2c device failed (error=%i)\n", ret);
+ em28xx_warn("failed to read i2c transfer status from "
+ "bridge (error=%i)\n", ret);
return ret;
}
- if (dev->em28xx_read_reg(dev, 0x5) != 0)
- return -ENODEV;
- return ret;
+ if (ret > 0) {
+ if (ret == 0x10) {
+ return -ENODEV;
+ } else {
+ em28xx_warn("unknown i2c error (status=%i)\n", ret);
+ return -EIO;
+ }
+ }
+ return len;
}
/*
* em28xx_i2c_check_for_device()
* check if there is a i2c_device at the supplied address
*/
-static int em28xx_i2c_check_for_device(struct em28xx *dev, unsigned char addr)
+static int em28xx_i2c_check_for_device(struct em28xx *dev, u16 addr)
{
int ret;
+ u8 buf;
- ret = dev->em28xx_read_reg_req(dev, 2, addr);
- if (ret < 0) {
- em28xx_warn("reading from i2c device failed (error=%i)\n", ret);
- return ret;
- }
- if (dev->em28xx_read_reg(dev, 0x5) != 0)
- return -ENODEV;
- return 0;
+ ret = em28xx_i2c_recv_bytes(dev, addr, &buf, 1);
+ if (ret == 1)
+ return 0;
+ return (ret < 0) ? ret : -EIO;
}
/*
@@ -253,11 +303,11 @@ static int em28xx_i2c_xfer(struct i2c_adapter *i2c_adap,
rc = em2800_i2c_check_for_device(dev, addr);
else
rc = em28xx_i2c_check_for_device(dev, addr);
- if (rc < 0) {
- dprintk2(2, " no device\n");
+ if (rc == -ENODEV) {
+ if (i2c_debug >= 2)
+ printk(" no device\n");
return rc;
}
-
} else if (msgs[i].flags & I2C_M_RD) {
/* read bytes */
if (dev->board.is_em2800)
@@ -288,16 +338,16 @@ static int em28xx_i2c_xfer(struct i2c_adapter *i2c_adap,
msgs[i].len,
i == num - 1);
}
- if (rc < 0)
- goto err;
+ if (rc < 0) {
+ if (i2c_debug >= 2)
+ printk(" ERROR: %i\n", rc);
+ return rc;
+ }
if (i2c_debug >= 2)
printk("\n");
}
return num;
-err:
- dprintk2(2, " ERROR: %i\n", rc);
- return rc;
}
/* based on linux/sunrpc/svcauth.h and linux/hash.h
@@ -329,7 +379,7 @@ static int em28xx_i2c_eeprom(struct em28xx *dev, unsigned char *eedata, int len)
{
unsigned char buf, *p = eedata;
struct em28xx_eeprom *em_eeprom = (void *)eedata;
- int i, err, size = len, block;
+ int i, err, size = len, block, block_max;
if (dev->chip_id == CHIP_ID_EM2874 ||
dev->chip_id == CHIP_ID_EM28174 ||
@@ -362,9 +412,15 @@ static int em28xx_i2c_eeprom(struct em28xx *dev, unsigned char *eedata, int len)
dev->name, err);
return err;
}
+
+ if (dev->board.is_em2800)
+ block_max = 4;
+ else
+ block_max = 64;
+
while (size > 0) {
- if (size > 16)
- block = 16;
+ if (size > block_max)
+ block = block_max;
else
block = size;
@@ -449,7 +505,11 @@ static int em28xx_i2c_eeprom(struct em28xx *dev, unsigned char *eedata, int len)
*/
static u32 functionality(struct i2c_adapter *adap)
{
- return I2C_FUNC_SMBUS_EMUL;
+ struct em28xx *dev = adap->algo_data;
+ u32 func_flags = I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+ if (dev->board.is_em2800)
+ func_flags &= ~I2C_FUNC_SMBUS_WRITE_BLOCK_DATA;
+ return func_flags;
}
static struct i2c_algorithm em28xx_algo = {
@@ -474,6 +534,7 @@ static struct i2c_client em28xx_client_template = {
* incomplete list of known devices
*/
static char *i2c_devs[128] = {
+ [0x3e >> 1] = "remote IR sensor",
[0x4a >> 1] = "saa7113h",
[0x52 >> 1] = "drxk",
[0x60 >> 1] = "remote IR sensor",
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-25 16:25:47 +0100