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| author | Mauro Carvalho Chehab <mchehab@redhat.com> | 2010-09-27 03:58:28 +0200 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2010-10-21 05:17:43 +0200 |
| commit | e350d44fed8eb86a7192a579e3687fcd76a4645b (patch) | |
| tree | 9e80c1c819150391729d7247e9f9d450d6edd11b /drivers/media/common | |
| parent | [media] cx231xx: Only change gpio direction when needed (diff) | |
| download | linux-e350d44fed8eb86a7192a579e3687fcd76a4645b.tar.xz linux-e350d44fed8eb86a7192a579e3687fcd76a4645b.zip | |
[media] tda18271: allow restricting max out to 4 bytes
By default, tda18271 tries to optimize I2C bus by updating all registers
at the same time. Unfortunately, some devices doesn't support it.
The current logic has a problem when small_i2c is equal to 8, since there
are some transfers using 11 + 1 bytes.
Fix the problem by enforcing the max size at the right place, and allows
reducing it to max = 3 + 1.
Acked-by: Michael Krufky <mkrufky@kernellabs.com>
Acked-by: Sri Deevi <Srinivasa.Deevi@conexant.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'drivers/media/common')
| -rw-r--r-- | drivers/media/common/tuners/tda18271-common.c | 59 | ||||
| -rw-r--r-- | drivers/media/common/tuners/tda18271.h | 5 |
2 files changed, 37 insertions, 27 deletions
diff --git a/drivers/media/common/tuners/tda18271-common.c b/drivers/media/common/tuners/tda18271-common.c index e1f678281a58..195b30e3872d 100644 --- a/drivers/media/common/tuners/tda18271-common.c +++ b/drivers/media/common/tuners/tda18271-common.c @@ -193,20 +193,46 @@ int tda18271_write_regs(struct dvb_frontend *fe, int idx, int len) unsigned char *regs = priv->tda18271_regs; unsigned char buf[TDA18271_NUM_REGS + 1]; struct i2c_msg msg = { .addr = priv->i2c_props.addr, .flags = 0, - .buf = buf, .len = len + 1 }; - int i, ret; + .buf = buf }; + int i, ret = 1, max; BUG_ON((len == 0) || (idx + len > sizeof(buf))); - buf[0] = idx; - for (i = 1; i <= len; i++) - buf[i] = regs[idx - 1 + i]; + + switch (priv->small_i2c) { + case TDA18271_03_BYTE_CHUNK_INIT: + max = 3; + break; + case TDA18271_08_BYTE_CHUNK_INIT: + max = 8; + break; + case TDA18271_16_BYTE_CHUNK_INIT: + max = 16; + break; + case TDA18271_39_BYTE_CHUNK_INIT: + default: + max = 39; + } tda18271_i2c_gate_ctrl(fe, 1); + while (len) { + if (max > len) + max = len; + + buf[0] = idx; + for (i = 1; i <= max; i++) + buf[i] = regs[idx - 1 + i]; - /* write registers */ - ret = i2c_transfer(priv->i2c_props.adap, &msg, 1); + msg.len = max + 1; + /* write registers */ + ret = i2c_transfer(priv->i2c_props.adap, &msg, 1); + if (ret != 1) + break; + + idx += max; + len -= max; + } tda18271_i2c_gate_ctrl(fe, 0); if (ret != 1) @@ -326,24 +352,7 @@ int tda18271_init_regs(struct dvb_frontend *fe) regs[R_EB22] = 0x48; regs[R_EB23] = 0xb0; - switch (priv->small_i2c) { - case TDA18271_08_BYTE_CHUNK_INIT: - tda18271_write_regs(fe, 0x00, 0x08); - tda18271_write_regs(fe, 0x08, 0x08); - tda18271_write_regs(fe, 0x10, 0x08); - tda18271_write_regs(fe, 0x18, 0x08); - tda18271_write_regs(fe, 0x20, 0x07); - break; - case TDA18271_16_BYTE_CHUNK_INIT: - tda18271_write_regs(fe, 0x00, 0x10); - tda18271_write_regs(fe, 0x10, 0x10); - tda18271_write_regs(fe, 0x20, 0x07); - break; - case TDA18271_39_BYTE_CHUNK_INIT: - default: - tda18271_write_regs(fe, 0x00, TDA18271_NUM_REGS); - break; - } + tda18271_write_regs(fe, 0x00, TDA18271_NUM_REGS); /* setup agc1 gain */ regs[R_EB17] = 0x00; diff --git a/drivers/media/common/tuners/tda18271.h b/drivers/media/common/tuners/tda18271.h index d7fcc36dc6e6..3abb221f3d07 100644 --- a/drivers/media/common/tuners/tda18271.h +++ b/drivers/media/common/tuners/tda18271.h @@ -80,8 +80,9 @@ enum tda18271_output_options { enum tda18271_small_i2c { TDA18271_39_BYTE_CHUNK_INIT = 0, - TDA18271_16_BYTE_CHUNK_INIT = 1, - TDA18271_08_BYTE_CHUNK_INIT = 2, + TDA18271_16_BYTE_CHUNK_INIT = 16, + TDA18271_08_BYTE_CHUNK_INIT = 8, + TDA18271_03_BYTE_CHUNK_INIT = 3, }; struct tda18271_config { |