From e350d44fed8eb86a7192a579e3687fcd76a4645b Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Sun, 26 Sep 2010 22:58:28 -0300 Subject: [PATCH] [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 Acked-by: Sri Deevi Signed-off-by: Mauro Carvalho Chehab --- drivers/media/common/tuners/tda18271-common.c | 59 +++++++++++-------- drivers/media/common/tuners/tda18271.h | 5 +- drivers/media/video/tuner-core.c | 2 +- 3 files changed, 38 insertions(+), 28 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 { diff --git a/drivers/media/video/tuner-core.c b/drivers/media/video/tuner-core.c index d14f66f0cb31..1cec1224913f 100644 --- a/drivers/media/video/tuner-core.c +++ b/drivers/media/video/tuner-core.c @@ -427,7 +427,7 @@ static void set_type(struct i2c_client *c, unsigned int type, { struct tda18271_config cfg = { .config = t->config, - .small_i2c = TDA18271_08_BYTE_CHUNK_INIT, + .small_i2c = TDA18271_03_BYTE_CHUNK_INIT, }; if (!dvb_attach(tda18271_attach, &t->fe, t->i2c->addr, -- 2.20.1